WO2025221706A1 - Dynamic power save with traffic type awareness - Google Patents

Abstract

A first station (STA) transmits to a second STA a first frame indicating a first traffic type that the second STA is allowed to transmit to the first STA while the first STA operates in a first power mode of a power save mode. The first STA receives from the second STA, and while the first STA operates in a second power mode of the power save mode, a second frame; and transitions, in response to the second frame, from the second power mode to the first power mode. The first STA receives from the second STA, and while the first STA operates in the first power mode, a third frame comprising one or more first data frames of the first traffic type.

Description

TITLE

Dynamic Power Save With Traffic Type Awareness

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63/634,529, filed April 16, 2024, and U.S. Provisional Application No. 63/734,272, filed December 16, 2024, both of which are hereby incorporated by reference in their entireties.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] Examples of several of the various embodiments of the present disclosure are described herein with reference to the drawings.

[0003] FIG. 1 illustrates example wireless communication networks in which embodiments of the present disclosure may be implemented.

[0004] FIG. 2 is a block diagram illustrating example implementations of a station (STA) and an access point (AP).

[0005] FIG. 3 illustrates an example medium access control (MAC) frame format.

[0006] FIG. 4 illustrates an example management frame which may be used as an action frame.

[0007] FIG. 5 illustrates an example control frame which may be used as a trigger frame.

[0008] FIG. 6 illustrates an example data frame which may be used as a Quality of Service (QoS) null frame.

[0009] FIG. 7 illustrates an example format of a physical layer (PHY) protocol data unit (PPDU).

[0010] FIG. 8 illustrates a non-High Throughput (non-HT) Physical Layer Protocol Data Unit (PPDU), a High Throughput (HT) mixed PPDU, and a Very High Throughput (VHT) PPDU.

[0011] FIG. 9 illustrates a High Efficiency (HE) Single User (SU) PPDU, an HE Multi-User (MU) PPDU, and an HE Extended Range (ER) SU PPDU

[0012] FIG. 10 illustrates an Extremely High Throughput (EHT) Multi-user (MU) PPDU.

[0013] FIG. 11 illustrates an example multi-user request-to-send (MU-RTS) trigger frame.

[0014] FIG. 12 illustrates an example block acknowledgment request (BlockAckReq or BAR) frame.

[0015] FIG. 13 illustrates an example of a power save (PS) mode.

[0016] FIG. 14 illustrates an example of an AP implementation of the PS mode illustrated in FIG. 13.

[0017] FIG. 15 illustrates an example that highlights a problem that may arise in association with the PS mode illustrated in FIG. 14.

[0018] FIG. 16 is an example that illustrates a PS mode procedure according to an embodiment.

[0019] FIG. 17 is an example that illustrates a PS mode procedure according to an embodiment.

[0020] FIG. 18 is an example that illustrates a PS mode procedure according to an embodiment.

[0021] FIG. 19 is an example that illustrates a PS mode procedure according to an embodiment.

[0022] FIG. 20 illustrates an example element of a management frame which may be used according to embodiment.

[0023] FIG. 21 illustrates an example process according to an embodiment of the present disclosure.

[0024] FIG. 22 illustrates an example process according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0025] In the present disclosure, various embodiments are presented as examples of how the disclosed techniques may be implemented and/or how the disclosed techniques may be practiced in environments and scenarios. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the scope. After reading the description, it will be apparent to one skilled in the relevant art how to implement alternative embodiments. The present embodiments may not be limited by any of the described exemplary embodiments. The embodiments of the present disclosure will be described with reference to the accompanying drawings. Limitations, features, and/or elements from the disclosed example embodiments may be combined to create further embodiments within the scope of the disclosure. Any figures which highlight the functionality and advantages, are presented for example purposes only. The disclosed architecture is sufficiently flexible and configurable, such that it may be utilized in ways other than that shown. For example, the actions listed in any flowchart may be re-ordered or only optionally used in some embodiments.

[0026] Embodiments may be configured to operate as needed. The disclosed mechanism may be performed when certain criteria are met, for example, in a station, an access point, a radio environment, a network, a combination of the above, and/or the like. Example criteria may be based, at least in part, on for example, wireless device or network node configurations, traffic load, initial system set up, packet sizes, traffic characteristics, a combination of the above, and/or the like. When the one or more criteria are met, various example embodiments may be applied. Therefore, it may be possible to implement example embodiments that selectively implement disclosed protocols.

[0027] In this disclosure, “a” and “an” and similar phrases are to be interpreted as “at least one” and “one or more.” Similarly, any term that ends with the suffix “(s)” is to be interpreted as “at least one” and “one or more.” In this disclosure, the term “may” is to be interpreted as “may, for example.” In other words, the term “may” is indicative that the phrase following the term “may” is an example of one of a multitude of suitable possibilities that may, or may not, be employed by one or more of the various embodiments. The terms “comprises” and “consists of”, as used herein, enumerate one or more components of the element being described. The term “comprises” is interchangeable with “includes” and does not exclude unenumerated components from being included in the element being described. By contrast, “consists of provides a complete enumeration of the one or more components of the element being described. The term “based on”, as used herein, may be interpreted as “based at least in part on” rather than, for example, “based solely on”. The term “and/or” as used herein represents any possible combination of enumerated elements. For example, “A, B, and/or C” may represent A; B; C; A and B; A and C; B and C; or A, B, and C.

[0028] If A and B are sets and every element of A is an element of B, A is called a subset of B. In this specification, only non-empty sets and subsets are considered. For example, possible subsets of B = {STA1, STA2) are: {STA1 }, {STA2}, and {STA1, STA2). The phrase “based on” (or equally “based at least on”) is indicative that the phrase following the term “based on” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “in response to” (or equally “in response at least to”) is indicative that the phrase following the phrase “in response to” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “depending on” (or equally “depending at least to”) is indicative that the phrase following the phrase “depending on” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “employi ng/using” (or equally “employing/using at least”) is indicative that the phrase following the phrase “employing/using” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments.

[0029] The term configured may relate to the capacity of a device whether the device is in an operational or non- operational state. Configured may refer to specific settings in a device that effect the operational characteristics of the device whether the device is in an operational or non-operational state. In other words, the hardware, software, firmware, registers, memory values, and/or the like may be “configured” within a device, whether the device is in an operational or nonoperational state, to provide the device with specific characteristics. Terms such as “a control message to cause in a device” may mean that a control message has parameters that may be used to configure specific characteristics or may be used to implement certain actions in the device, whether the device is in an operational or non-operational state.

[0030] In this disclosure, parameters (or equally called, fields, or Information elements: lEs) may comprise one or more information objects, and an information object may comprise one or more other objects. For example, if parameter (IE) N comprises parameter (IE) M, and parameter (IE) M comprises parameter (IE) K, and parameter (IE) K comprises parameter (information element) J. Then, for example, N comprises K, and N comprises J. In an example embodiment, when one or more messages/frames comprise a plurality of parameters, it implies that a parameter in the plurality of parameters is in at least one of the one or more messages/frames but does not have to be in each of the one or more messages/frames.

[0031] Many features presented are described as being optional through the use of “may” or the use of parentheses. For the sake of brevity and legibility, the present disclosure does not explicitly recite each and every permutation that may be obtained by choosing from the set of optional features. The present disclosure is to be interpreted as explicitly disclosing all such permutations. For example, a system described as having three optional features may be embodied in seven ways, namely with just one of the three possible features, with any two of the three possible features or with three of the three possible features.

[0032] Many of the elements described in the disclosed embodiments may be implemented as modules. A module is defined here as an element that performs a defined function and has a defined interface to other elements. The modules described in this disclosure may be implemented in hardware, software in combination with hardware, firmware, wetware (e g., hardware with a biological element) or a combination thereof, which may be behaviorally equivalent. For example, modules may be implemented as a software routine written in a computer language configured to be executed by a hardware machine (such as C, C++, Fortran, Java, Basic, Matlab or the like) or a modeling/simulation program such as Simulink, Stateflow, GNU Octave, or LabVIEWMathScript. It may be possible to implement modules using physical hardware that incorporates discrete or programmable analog, digital and/or quantum hardware. Examples of programmable hardware comprise computers, microcontrollers, microprocessors, application-specific integrated circuits (ASICs); field programmable gate arrays (FPGAs); and complex programmable logic devices (CPLDs). Computers, microcontrollers, and microprocessors are programmed using languages such as assembly, C, C++ or the like. FPGAs, ASICs and CPLDs are often programmed using hardware description languages (HDL) such as VHSIC hardware description language (VHDL) or Verilog that configure connections between internal hardware modules with lesser functionality on a programmable device. The mentioned technologies are often used in combination to achieve the result of a functional module.

[0033] FIG. 1 illustrates example wireless communication networks in which embodiments of the present disclosure may be implemented.

[0034] As shown in FIG. 1, the example wireless communication networks may include an Institute of Electrical and Electronic Engineers (IEEE) 802.11 (WLAN) infra-structure network 102. WLAN infra-structure network 102 may include one or more basic service sets (BSSs) 110 and 120 and a distribution system (DS) 130.

[0035] BSS 110-1 and 110-2 each includes a set of an access point (AP or AP STA) and at least one station (STA or non-AP STA). For example, BSS 110-1 includes an AP 104-1 and a STA 106-1, and BSS 110-2 includes an AP 104-2 and STAs 106-2 and 106-3. The AP and the at least one STA in a BSS perform an association procedure to communicate with each other.

[0036] DS 130 may be configured to connect BSS 110-1 and BSS 110-2. As such, DS 130 may enable an extended service set (ESS) 150. Within ESS 150, APs 104-1 and 104-2 are connected via DS 130and may have the same service set identification (SSID).

[0037] WLAN infra-structure network 102 may be coupled to one or more external networks. For example, as shown in FIG. 1, WLAN infra-structure network 102 may be connected to another network 108 (e.g., 802.X) via a portal 140. Portal 140 may function as a bridge connecting DS 130 of WLAN infra-structure network 102 with the other network 108. [0038] The example wireless communication networks illustrated in FIG. 1 may further include one or more ad-hoc networks or independent BSSs (IBSSs). An ad-hoc network or IBSS is a network that includes a plurality of STAs that are within communication range of each other. The plurality of STAs are configured so that they may communicate with each other using direct peer-to-peer communication (i.e., not via an AP).

[0039] For example, in FIG. 1, STAs 106-4, 106-5, and 106-6 may be configured to form a first IBSS 112-1. Similarly, STAs 106-7 and 106-8 may be configured to form a second IBSS 112-2. Since an IBSS does not include an AP, it does not include a centralized management entity. Rather, STAs within an IBSS are managed in a distributed manner. STAs forming an IBSS may be fixed or mobile.

[0040] A STA as a predetermined functional medium may include a medium access control (MAC) layer that complies with an IEEE 802.11 standard. A physical layer interface for a radio medium may be used among the APs and the non- AP stations (STAs). The STA may also be referred to using various other terms, including mobile terminal, wireless device, wireless transmit/receive unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, or user. For example, the term “user” maybe used to denote a STA participating in uplink Multi-user Multiple Input, Multiple Output (MU MIMO) and/or uplink Orthogonal Frequency Division Multiple Access (OFDMA) transmission. [0041] A physical layer (PHY) protocol data unit (PPDU) may be a composite structure that includes a PHY preamble and a payload in the form of a PLCP service data unit (PSDU). For example, the PSDU may include a PHY Convergence Protocol (PLCP) preamble and header and/or one or more MAC protocol data units (MPDUs). The information provided in the PHY preamble may be used by a receiving device to decode the subsequent data in the PSDU. In instances in which PPDUs are transmitted over a bonded channel (channel formed through channel bonding), the preamble fields may be duplicated and transmitted in each of the multiple component channels. The PHY preamble may include both a legacy portion (or “legacy preamble”) and a non-legacy portion (or “non-legacy preamble”). The legacy preamble may be used for packet detection, automatic gain control and channel estimation, among other uses. The legacy preamble also may generally be used to maintain compatibility with legacy devices. The format of, coding of, and information provided in the non-legacy portion of the preamble is based on the particular IEEE 802.11 protocol to be used to transmit the payload.

[0042] A frequency band may include one or more sub-bands or frequency channels. For example, PPDUs conforming to the IEEE 802.11n, 802.11ac, 802.11 ax and/or 802.11 be standard amendments may be transmitted over the 2.4 GHz, 5 GHz, and/or 6 GHz bands, each of which may be divided into multiple 20 MHz channels. The PPDUs may be transmitted over a physical channel having a minimum bandwidth of 20 MHz. Larger channels may be formed through channel bonding. For example, PPDUs may be transmitted over physical channels having bandwidths of 40 MHz, 80 MHz, 160 MHz, or 520 MHz by bonding together multiple 20 MHz channels.

[0043] FIG. 2 is a block diagram illustrating example implementations of a STA 210 and an AP 260. As shown in FIG. 2, STA 210 may include at least one processor 220, a memory 230, and at least one transceiver 240. AP 260 may include at least one processor 270, a memory 280, and at least one transceiver 290. Processor 220/270 may be operatively connected to memory 230/280 and/or to transceiver 240/290.

[0044] Processor 220/270 may implement functions of the PHY layer, the MAC layer, and/or the logical link control (LLC) layer of the corresponding device (STA 210 or AP 260). Processor 220/270 may include one or more processors and/or one or more controllers. The one or more processors and/or one or more controllers may comprise, for example, a general-purpose processor, a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a logic circuit, or a chipset, for example.

[0045] Memory 230/280 may include a read-only memory (ROM), a random-access memory (RAM), a flash memory, a memory card, a storage medium, and/or other storage unit. Memory 230/280 may comprise one or more non-transi tory computer readable mediums. Memory 230/280 may store computer program instructions or code that may be executed by processor 220/270 to carry out one or more of the operations/embodiments discussed in the present application. Memory 230/280 may be implemented (or positioned) within processor 220/270 or external to processor 220/270. Memory 230/280 may be operatively connected to processor 220/270 via various means known in the art.

[0046] Transceiver 240/290 may be configured to transmit/receive radio signals. In an embodiment, transceiver 240/290 may implement a PHY layer of the corresponding device (STA 210 or AP 260). In an embodiment, STA 210 and/or AP 260 may be a multi-link device (MLD), that is a device capable of operating over multiple links as defined by the IEEE 802.11 standard. As such, STA 210 and/or AP 260 may each implement multiple PHY layers. The multiple PHY layers may be implemented using one or more of transceivers 240/290.

[0047] FIG. 3 illustrates an example format of a MAC frame 300. In operation, a STA may construct a subset of MAC frames for transmission and may decode a subset of received MAC frames upon validation. The particular subsets of frames that a STA may construct and/or decode may be determined by the functions supported by the STA. A STA may validate a received MAC frame using the frame check sequence (FCS) contained in the frame and may interpret certain fields from the MAC headers of all frames.

[0048] As shown in FIG. 3, MAC frame 300 includes a MAC header, a variable length frame body, and a frame check sequence (FCS).

[0049] The MAC header includes a frame control field, an optional duration/ID field (not in PS-Poll frames), address fields, an optional sequence control field, an optional QoS control field (only in QoS Data frames), and an optional high throughput (HT) control field (only in +HTC frames).

[0050] The frame control field includes the following subfields: protocol version, type, subtype, To DS, From DS, more fragments, retry, power management, more data, protected frame, and high throughput control (+HTC).

[0051] The protocol version subfield is invariant in size and placement across all revisions of the IEEE 802.11 standard. The value of the protocol version subfield is 0 for MAC frames.

[0052] The type and subtype subfields together identify the function of the MAC frame. There are three frame types: control, data, and management. Each of the frame types has several defined subtypes. Bits within the subtype subfield are used to indicate a specific modification of the basic data frame (subtype 0). For example, in data frames, the most significant bit (MSB) of the subtype subfield, bit 7 (B7) of the frame control field, is defined as the QoS subfield. When the QoS subfield is set to 1, it indicates a QoS subtype data frame, which is a data frame that contains a QoS control field in its MAC header. The second MSB of the subtype field, bit 6 (B6) of the frame control field, when set to 1 in data subtypes, indicates a data frame that contains no frame body field.

[0053] The To DS subfield indicates whether a data frame is destined to the DS. The From DS subfield indicates whether a data frame originates from the DS.

[0054] The more fragments subfield is set to 1 in all data or management frames that have another fragment to follow of the MAC service data unit (MSDU) or MAC management protocol data unit (MMPDU) carried by the MAC frame. It is set to 0 in all other frames in which the more fragments subfield is present.

[0055] The retry subfield is set to 1 in any data or management frame that is a retransmission of an earlier frame. It is set to 0 in all other frames in which the retry subfield is present. A receiving STA uses this indication to aid it in the process of eliminating duplicate frames. These rules do not apply for frames sent by a STA under a block agreement.

[0056] The power management subfield is used to indicate the power management mode of a STA.

[0057] The More Data subfield indicates to a STA in power save (PS) mode that bufferable units (BUs) are buffered for that STA at the AP. The more data subfield is valid in individually addressed data or management frames transmitted by an AP to a STA in PS mode. The more data subfield is set to 1 to indicate that at least one additional buffered BU is present for the STA.

[0058] The protected frame subfield is set to 1 if the frame body field contains information that has been processed by a cryptographic encapsulation algorithm.

[0059] The +HTC subfield indicates that MAC frame 300 contains an HT control field. A frame that contains the HT Control field is referred to as a +HTC frame. A Control Wrapper frame is a +HTC frame.

[0060] The duration/ID field of the MAC header indicates various contents depending on frame type and subtype and the QoS capabilities of the sending STA. For example, in control frames of the power save poll (PS-Poll) subtype, the duration/ID field carries an association identifier (AID) of the STA that transmitted the frame in the 14 least significant bits (LSB), and the 2 most significant bits (MSB) are both set to 1 . In otherframes sent by STAs, the duration/ID field contains a duration value (in microseconds) which is used by a recipient to update a network allocation vector (NAV). The NAV is a counter that indicates to a STA an amount of time during which it must defer from accessing the shared medium

[0061] There can be up to four address fields in the format of MAC frame 300. These fields are used to indicate the basic service set identifier (BSSID), source address (SA), destination address (DA), transmitter address (TA), and receiver address (RA). Certain frames might not contain some of the address fields. Certain address field usage may be specified by the relative position of the address field (1-4) within the MAC header, independent of the type of address present in that field. Specifically, the address 1 field always identifies the intended receiver(s) of the frame, and the address 2 field, where present, always identifies the transmitter of the frame.

[0062] The sequence control field includes two subfields, a sequence number subfield and a fragment number subfield. The sequence number subfield in data frames indicates the sequence number of the MSDU (if not in an Aggregated MSDU (A-MSDU)) or A-MSDU. The sequence number subfield in management frames indicates the sequence number of the frame. The fragment number subfield indicates the number of each fragment of an MSDU or MMPDU. The fragment number is set to 0 in the first or only fragment of an MSDU or MMPDU and is incremented by one for each successive fragment of that MSDU or MMPDU. The fragment number is set to 0 in a MAC protocol data unit (MPDU) containing an A-MSDU, or in an MPDU containing an MSDU or MMPDU that is not fragmented. The fragment number remains constant in all retransmissions of the fragment.

[0063] The QoS control field identifies the traffic category (TC) or traffic stream (TS) to which MAC frame 300 belongs. The QoS control field may also indicate various other QoS related, A-MSDU related, and mesh-related information about the frame. This information can vary by frame type, frame subtype, and type of transmitting STA. The QoS control field is present in all data frames in which the QoS subfield of the subtype subfield is equal to 1.

[0064] The HT control field is present in QoS data, QoS null, and management frames as determined by the +HTC subfield of the frame control field. The control frame subtype for which HT control field is present is the control wrapper frame. A control frame that is described as +HTC (e.g., a request to send (RTS)+HTC, clear to send (CTS)+HTC, block acknowledgment (BlockAck)+HTC or block acknowledgment request (BlockAckReq)+HTC frame) implies the use of the control wrapper frame to carry that control frame. [0065] The frame body field is a variable length field that contains information specific to individual frame types and subtypes. It may include one or more MSDUs or MMPDUs. The minimum length of the frame body is 0 octets.

[0066] The FCS field contains a 32-bit Cyclic Redundancy Check (CRC) code. The FCS field value is calculated over all of the fields of the MAC header and the frame body field.

[0067] FIG. 4 illustrates an example management frame 400 which may be used as an action frame. In an example, management frame 400 includes a MAC header, a variable length frame body, and a frame check sequence (FCS). The MAC header includes a frame control field, a duration field, an address 1 field, an address 2 field, an address 3 field, a sequence control field, and an optional HT control field. The presence of the HT control field is determined by the setting of a +HTC subfield of the frame control field.

[0068] As shown in FIG. 4, when used as an action frame, the frame body of management frame includes an action field, vendor specific elements, management message integrity code element (MME), message integrity code (MIC), and an authenticated mesh peering exchange element.

[0069] The action field includes a category field and an action details field. The action field provides a mechanism for specifying extended management actions. The category field indicates a category of the action frame. The action details field contains the details of the action requested by the action frame. For example, the action frame may be a public action frame. As shown in FIG. 4, in the public action frame format, the action details field includes a public action field, in the octet immediately after the category field, followed by a variable length public action details field.

[0070] One or more vendor specific elements are optionally present. These elements are absent when the category subfield of the Action field is vendor-specific.

[0071] The MME is present when management frame protection is negotiated, the frame is a group addressed robust Action frame, and (MBSS only) the category of the action frame does not support group addressed privacy as indicated by category values; otherwise not present.

[0072] The MIC element is present in a self-protected action frame if a shared pairwise master key (PMK) exists between the sender and recipient of this frame; otherwise not present.

[0073] The authenticated mesh peering exchange element is present in a self-protected action frame if a shared PMK exists between the sender and recipient of this frame; otherwise not present.

[0074] FIG. 5 illustrates an example format of a trigger frame 500. Trigger frame 500 may be used by an AP to allocate resources for and solicit one or more TB PPDU transmissions from one or more STAs. Trigger frame 500 may also carry other information required by a responding STA to transmit a TB PPDU to the AP.

[0075] As shown in FIG 5, trigger frame 500 includes a Frame Control field, a Duration field, a receiver address (RA) field, a transmitter address (TA) field, a Common Info field, a User Info List field, a Padding field, and an FCS field.

[0076] The Frame Control field includes the following subfields: protocol version, type, subtype, To DS, From DS, more fragments, retry, power management, more data, protected frame, and +HTC.

[0077] The Duration field indicates various contents depending on frame type and subtype and the QoS capabilities of the sending STA. For example, in control frames of the power save poll (PS-Poll) subtype, the Duration field carries an association identifier (AID) of the STA that transmitted the frame in the 14 least significant bits (LSB), and the 2 most significant bits (MSB) are both set to 1. In other frames sent by STAs, the Duration field contains a duration value (in microseconds) which is used by a recipient to update a network allocation vector (NAV).

[0078] The RA field is the address of the STA that is intended to receive the incoming transmission from the transmitting station. The TA field is the address of the STA transmitting trigger frame 500 if trigger frame 500 is addressed to STAs that belong to a single BSS. The TA field is the transmitted BSSI D if trigger frame 500 is addressed to STAs from at least two different BSSs of the multiple BSSID set.

[0079] The Common Info field specifies a trigger frame type of trigger frame 500, a transmit power of trigger frame 500 in dBm, and several key parameters of a TB PPDU that is transmitted by a STA in response to trigger frame 500. The trigger frame type of a trigger frame used by an AP to receive QoS data using UL MU operation is referred to as a basic trigger frame. A non-EHT non-AP HE STA interprets the Common Info field as HE variant. A non-AP EHT STA interprets the Common Info field as HE variant if B54 and B55 in the Common Info field are equal to 1 ; and interprets the Common Info field as EHT variant otherwise. The HE variant Common Info field and the EHT variant Common Info field use the same encoding method for the Trigger Type, UL Length, More TF, CS Required, LDPC Extra Symbol Segment, AP TX Power, Pre-FEC Padding Factor, PE Disambiguity, and Trigger Dependent Common Info subfields.

[0080] The User Info List field contains zero or more User Info fields. There are three variants for the User Info field, which are the Special User Info field, the EHT variant User Info field, and the HE variant User Info field.

[0081] The Special User Info field is a User Info field that does not carry the user specific information but carries the extended common information not provided in the Common Info field. If the Special User Info field is included in the Trigger frame, then the Special User Info Field Flag subfield of the EHT variant Common Info field is set to 0, otherwise it is set to 1. The Special User Info field is identified by an AID12 value of 2007 and is optionally present in a Trigger frame that is generated by an EHT AP. The Special User Info field, if present, is located immediately after the Common Info field of the Trigger frame and carries information for the U-SIG field of a solicited EHT TB PPDU. The PHY Version Identifier subfield indicates the PHY version of the solicited TB PPDU that is not an HE TB PPDU. The PHY Version Identifier subfield is set to 0 for EHT. Other values from 1 to 7 are reserved. The UL Bandwidth (BW) Extension subfield, together with the UL BW subfield in the Common Info field, indicates the bandwidth of the solicited TB PPDU from the addressed EHT STA (i.e., the bandwidth in the U-SIG field of the EHT TB PPDU). The EHT Spatial Reuse n subfield carries the values to be included in the corresponding Spatial Reuse n subfield in the U-SIG field of the EHT TB PPDU. The U-SIG Disregard And Validate subfield carries the values to be included in the Disregard and Validate subfields of the U-SIG field of the solicited EHT TB PPDUs. The presence and length of the Trigger Dependent User Info subfield in the Special User Info field depends on the variant of the Trigger frame.

[0082] The EHT variant User Info field contains a User Info field per STA addressed in trigger frame 500. The per STA User Info field includes, among others, an AID12 subfield, an RU Allocation subfield, a UL FEC Coding Type subfield, a UL EHT-MCS subfield, a Reserved subfield, a Spatial Stream (SS) Allocation/RA-RU information subfield, a UL Target Receive Power subfield, and a Power Save (PS) 160 subfield to be used by a STA in a TB PPDU transmitted in response to trigger frame 500, and a Trigger Dependent User Info subfield. The RU Allocation subfield in an EHT variant User Info field in a Trigger frame that is notan MU-RTS Trigger frame, along with the UL BW subfield in the Common Info field, the UL BW Extension subfield in the Special User Info field, and the PS160 subfield in the EHT variant User Info field, identifies the size and the location of the RU or MRU. The values of PS 160 subfield and BO of RU Allocation subfield indicate the 80 MHz frequency subblock in which the RU or MRU is located for 26-tone RU, 52-tone RU, 106-tone RU, 242-tone RU, 484-tone RU, 996-tone RU, 52+26-tone RU, and 106+26-tone RU. The values of PS160 subfield indicates the 160 MHz segment in which the RU or MRU is located for 20996-tone RU, 996+484-tone MRU, and 996+484+242- tone MRU. The UL FEC Coding Type subfield of the User Info field indicates the code type of the solicited EHT TB PPDU. The UL FEC Coding Type subfield is set to 0 to indicate BCC and set to 1 to indicate LDPC. The UL EHT-MCS subfield of the User Info field indicates the EHT-MCS of the solicited EHT TB PPDU. The SS Allocation subfield of the EHT variant User Info field indicates the spatial streams of the solicited EHT TB PPDU. The UL Target Receive Power subfield indicates the expected receive signal power, measured at the AP’s antenna connector and averaged over the antennas, for the EHT portion of the EHT TB PPDU transmitted on the assigned RU. The Trigger Dependent User Info subfield can be used by an AP to specify a preferred access category (AC) per STA. The preferred AC sets the minimum priority AC traffic that can be sent by a participating STA. The AP determines the list of participating STAs, along with the BW, MCS, RU allocation, SS allocation, Tx power, preferred AC, and maximum duration of the TB PPDU per participating STA. The RA-RU Information subfield is reserved in the EHT variant User Info field.

[0083] The Padding field is optionally present in trigger frame 400 to extend the frame length to give recipient STAs enough time to prepare a response for transmission one SIFS after the frame is received. The Padding field, if present, is at least two octets in length and is set to all 1s.

[0084] The FCS field is used by a STA to validate a received frame and to interpret certain fields from the MAC headers of a frame.

[0085] FIG. 6 illustrates an example data frame 600 which may be used as a QoS null frame. A QoS null frame refers to a QoS data frame with an empty frame body. QoS null frame includes a QoS control field and an optional HT control field which may contain a buffer status report (BSR) control subfield. A QoS null frame indicating buffer status information may be transmitted by a STA to an AP.

[0086] The QoS control field may include a traffic identifier (TID) subfield, an acknowledgment (Ack) policy indicator subfield, and a queue size subfield (or a transmission opportunity (TXOP) duration requested subfield).

[0087] The TID subfield identifies the TC or TS of traffic for which a TXOP is being requested, through the setting of the TXOP duration requested or queue size subfield. The encoding of the TID subfield depends on the access policy (e.g., Allowed value 0 to 7 for enhanced distributed channel access (EDCA) access policy to identify user priority for either TC or TS).

[0088] The ack policy indicator subfield, together with other information, identifies the Ack policy followed upon delivery of the MPDU (e.g., normal Ack, implicit block Ack request, no Ack, block Ack, etc.) [0089] The queue size subfield is an 8-bit field that indicates the amount of buffered traffic for a given TC or TS at the STA for transmission to the AP identified by the receiver address of the frame containing the subfield. The queue size subfield is present in QoS null frames sent by a STA when bit 4 of the QoS control field is set to 1. The AP may use information contained in the queue size subfield to determine the TXOP duration assigned to the STA or to determine the uplink (UL) resources assigned to the STA.

[0090] In a frame sent by or to a non-high efficiency (non-HE) STA, the following rules may apply to the queue size value:

The queue size value is the approximate total size, rounded up to the nearest multiple of 256 octets and expressed in units of 256 octets, of all MSDUs and A-MSDUs buffered at the STA (excluding the MSDU or A-MSDU contained in the present QoS Data frame) in the delivery queue used for MSDUs and A-MSDUs with TID values equal to the value indicated in the TID subfield of the QoS Control field.

A queue size value of 0 is used solely to indicate the absence of any buffered traffic in the queue used for the specified TID.

A queue size value of 254 is used for all sizes greater than 64768 octets.

A queue size value of 255 is used to indicate an unspecified or unknown size.

[0091] In a frame sent by an HE STA to an HE AP, the following rules may apply to the queue size value.

[0092] The queue size value, QS, is the approximate total size in octets, of all MSDUs and A-MSDUs buffered at the STA (including the MSDUs or A-MSDUs contained in the same PSDU as the frame containing the queue size subfield) in the delivery queue used for MSDUs and A-MSDUs with TID values equal to the value indicated in the TID subfield of the QoS control field.

[0093] The queue size subfield includes a scaling factor subfield in bits B14-B15 of the QoS control field and an unsealed value, UV, in bits B8-B13 of the QoS control field. The scaling factor subfield provides the scaling factor, SF. [0094] A STA obtains the queue size, QS, from a received QoS control field, which contains a scaling factor, SF, and an unsealed value, UV, as follows:

QS =

16 xUV, if SF is equal to O;

1024 + 256 x UV, if SF is equal to 1;

17408 + 2048 x Ul/, if SF is equal to 2;

148480 + 32768 x UV, if SF is equal to 3 and UV is less than 62;

> 2 147328, if SF equal to is 3 and UV is equal to 62;

Unspecified or Unknown, if SF is equal to 3 and UV is equal to 63.

[0095] The TXOP duration requested subfield, which may be included instead of the queue size subfield, indicates the duration, in units of 32 microseconds (us), that the sending STA determines it needs for its next TXOP for the specified TID. The TXOP duration requested subfield is set to 0 to indicate that no TXOP is requested for the specified TID in the current service period (SP). The TXOP duration requested subfield is set to a nonzero value to indicate a requested TXOP duration in the range of 32 us to 8160 us in increments of 32 us.

[0096] The HT control field may include an aggregated control (A-Control) subfield. The A-Control subfield may include a control list subfield including one or more control subfields.

[0097] The control subfield may be a BSR control subfield, which may contain buffer status information used for UL MU operation. The BSR control subfield may be formed from an access category index (ACI) bitmap subfield, a delta TID subfield, an ACI high subfield, a scaling factor subfield, a queue size high subfield, and a queue size all subfield of the HT control field.

[0098] The ACI bitmap subfield indicates the access categories for which buffer status is reported (e.g ., B0: best effort (AC_BE), B1: background (AC_BK), B2: video (AC_VI), B3: voice (AC_VO), etc.). Each bitof the ACI bitmap subfield is set to 1 to indicate that the buffer status of the corresponding AC is included in the queue size all subfield, and set to 0 otherwise, except that if the ACI bitmap subfield is 0 and the delta TID subfield is 3, then the buffer status of all 8 TIDs is included.

[0099] The delta Tl D subfield, together with the values of the ACI bitmap subfield, indicate the number of Tl Ds for which the STA is reporting the buffer status.

[0100] The ACI high subfield indicates the ACI of the AC for which the BSR is indicated in the queue size high subfield. The ACI to AC mapping is defined as ACI value 0 mapping to AC_BE, ACI value 1 mapping to AC_BK, ACI value 2 mapping to AC_VI, and ACI value 3 mapping to AC_VO.

[0101] The scaling factor subfield indicates the unit SF, in octets, of the queue size high and queue size all subfields. [0102] The queue size high subfield indicates the amount of buffered traffic, in units of SF octets, for the AC identified by the ACI high subfield, that is intended for the STA identified by the receiver address of the frame containing the BSR control subfield.

[0103] The queue size all subfield indicates the amount of buffered traffic, in units of SF octets, for all ACs identified by the ACI Bitmap subfield, that is intended for the STA identified by the receiver address of the frame containing the BSR control subfield.

[0104] The queue size values in the queue size high and queue size all subfields are the total sizes, rounded up to the nearest multiple of SF octets, of all MSDUs and A-MSDUs buffered at the STA (including the MSDUs or A-MSDUs contained in the same PSDU as the frame containing the BSR control subfield) in delivery queues used for MSDUs and A-MSDUs associated with AC(s) that are specified in the ACI high and ACI bitmap subfields, respectively.

[0105] A queue size value of 254 in the queue size high and queue size all subfields indicates that the amount of buffered traffic is greater than 254 ^x SF octets. A queue size value of 255 in the queue size high and queue size all subfields indicates that the amount of buffered traffic is an unspecified or unknown size. The queue size value of QoS data frames containing fragments may remain constant even if the amount of queued traffic changes as successive fragments are transmitted. [0106] MAC service provides peer entities with the ability to exchange MSDUs. To support this service, a local MAC uses the underlying PHY-level service to transport the MSDUs to a peer MAC entity. Such asynchronous MSDU transport is performed on a connectionless basis.

[0107] FIG. 7 illustrates an example format of a PPDU. As shown, the PPDU may include a PHY preamble, a PHY header, a PSDU, and tail and padding bits.

[0108] The PSDU may include one or more MPDUs, such as a QoS data frame, an MMPDU, a MAC control frame, or a QoS null frame. In the case of an MPDU carrying a QoS data frame, the frame body of the MPDU may include a MSDU or an A-MSDU.

[0109] By default, MSDU transport is on a best-effort basis. That is, there is no guarantee that a transmitted MSDU will be delivered successfully. However, the QoS facility uses a traffic identifier (TID) to specify differentiated services on a per-MSDU basis.

[0110] A STA may differentiate MSDU delivery according to designated traffic category (TC) or traffic stream (TS) of individual MSDUs. The MAC sublayer entities determine a user priority (UP) for an MSDU based on a TID value provided with the MSDU. The QoS facility supports eight UP values. The UP values range from 0 to 7 and form an ordered sequence of priorities, with 1 being the lowest value, 7 the highest value, and 0 falling between 2 and 3.

[0111] An MSDU with a particular UP is said to belong to a traffic category with that UP. The UP may be provided with each MSDU at the medium access control service access point (MAC SAP) directly in an UP parameter. An A-MPDU may include MPDUs with different TID values.

[0112] A STA may deliver buffer status reports (BSRs) to assist an AP in allocating UL MU resources. The STA may either implicitly deliver BSRs in the QoS control field or BSR control subfield of any frame transmitted to the AP (unsolicited BSR) or explicitly deliver BSRs in a frame sent to the AP in response to a BSRP Trigger frame (solicited BSR).

[0113] The buffer status reported in the QoS control field includes a queue size value for a given TID. The buffer status reported in the BSR control field includes an ACI bitmap, delta TID, a high priority AC, and two queue sizes.

[0114] A STA may report buffer status to the AP, in the QoS control field, of transmitted QoS null frames and QoS data frames and, in the BSR control subfield (if present), of transmitted QoS null frames, QoS data frames, and management frames as defined below.

[0115] The STA may report the queue size for a given TID in the queue size subfield of the QoS control field of transmitted QoS data frames or QoS null frames; the STA may set the queue size subfield to 255 to indicate an unknown/unspecified queue size for that TID The STA may aggregate multiple QoS data frames or QoS null frames in an A-MPDU to report the queue size for different TIDs.

[0116] The STA may report buffer status in the BSR control subfield of transmitted frames if the AP has indicated its support for receiving the BSR control subfield. [0117] A High-Efficiency (HE) STA may report the queue size for a preferred AC, indicated by the ACI high subfield, in the queue size high subfield of the BSR control subfield. The STA may set the queue size high subfield to 255 to indicate an unknown/unspecified queue size for that AC

[0118] A HE STA may report the queue size for ACs indicated by the ACI bitmap subfield in the queue size all subfield of the BSR control subfield. The STA may set the queue size all subfield to 255 to indicate an unknown/unspecified BSR for those ACs.

[0119] Enhanced distributed channel access (EDCA) is a listen-before-talk access mechanism that allows exactly one STA to access a channel and to transmit a PPDU in a given time slot. Before transmission using EDCA, a STA listens to the channel for a minimum of an Arbitration Interframe Space (AIFS) duration to determine whether the channel state is I DLE. This listening time for determining whether the channel is I DLE may be followed by one or more backoff slots before the STA attempts to transmit over the channel. The number of backoff slots is chosen randomly by the STA. This reduces the probability of multiple STAs attempting to transmit at the same time, which would result in a packet detect error. If the PPDU transmitted by the STA is received successfully, for example by an AP (not shown in the figure), the AP may respond with an acknowledgment (ACK) frame after a Short Interframe Space (SIFS) duration of receiving the PPDU.

[0120] The EDCA mechanism provides differentiated, distributed access to the WM for STAs using eight different UPs. The EDCA mechanism defines four access categories (ACs) that provide support for the delivery of traffic with UPs at the STAs.

[0121] The four ACs include AC for best effort (AC_BE), AC for background (AC_BK), AC for video (AC_VI), and AC for voice (AC_V0).

[0122] The EDCA channel access protocol is derived from the DCF procedures by adding four independent enhanced distributed channel access functions (EDCAFs) to provide differentiated priorities to transmitted traffic, through the use of four different ACs.

[0123] An access category (AC) is a label for the common set of EDCA parameters that are used by a qual i ty-of-service (QoS) station (STA) to contend for the channel in order to transmit medium access control (MAC) service data units (MSDUs) with certain priorities.

[0124] A traffic category (TC) is a label for medium access control (MAC) service data units (MSDUs) that have a distinct user priority (UP), as viewed by higher layer entities, relative to other MSDUs provided for delivery over the same link. TCs are meaningful only to MAC entities that support quality of service (QoS) within the MAC data service. These MAC entities determine the UP for MSDUs belonging to a particular traffic category using the priority value provided with those MSDUs at the MAC service access point (MAC SAP).

[0125] A traffic identifier (TID) is any of the identifiers usable by higher layer entities to distinguish medium access control (MAC) service data units (MSDUs) to MAC entities that support quality of service (QoS) within the MAC data service.

[0126] A traffic specification (TSPEC) is the quality-of-service (QoS) characteristics of a data flow to and from a QoS station (STA). A TSPEC describes the traffic characteristics and the QoS requirements of a TS. The main purpose of the TSPEC is to reserve resources within the HC and, in the case of HCCA and HEMM access policies, to modify the HC’s scheduling behavior. It also allows other parameters to be specified that are associated with the TS, such as a traffic classifier and ack policy.

[0127] Traffic classification (TCLAS) is the specification of one of several types of matching filter to classify protocol data units (PDUs) or medium access control (MAC) service data units (MSDUs) as belonging to a particular traffic stream (TS). Depending on the type of classification, the filter is applied within the MAC sublayer management entity (MLME), above the MAC, or within the MAC itself.

[0128] A traffic stream (TS) is a set of medium access control (MAC) service data units (MSDUs) to be delivered subject to the quality-of-service (QoS) parameter values provided to the MAC in a particular traffic specification (TSPEC). TSs are meaningful only to MAC entities that support QoS within the MAC data service. These MAC entities determine the TSPEC applicable for delivery of MSDUs belonging to a particular TS using the priority parameter provided with those MSDUs at the MAC service access point (MAC SAP). A TS may have one or more TCLAS (within the discretion of the STA that sets up the stream) associated with it.

[0129] A traffic stream identifier (TSID) is any of the identifiers usable by higher layer entities to distinguish medium access control (MAC) service data units (MSDUs) to MAC entities for parameterized quality of service (QoS), i.e., the traffic stream (TS) with a particular traffic specification (TSPEC), within the MAC data service. The TSID is assigned to an MSDU in the layers above the MAC.

[0130] Stream classification service (SCS) is a service that may be provided by an AP to its associated STAs that support SCS. In SCS, the AP classifies incoming individually addressed MSDUs based upon parameters provided by the non-AP STA.

[0131] The classification allows the UP, drop eligibility, and EDCA transmit queue to be selected for all MSDUs matching the classification.

[0132] A non-AP STA that supports SCS may request use of SCS by sending an SCS Request frame that includes an SCS Descriptor element with the Request Type field set to “Add” or “Change." The SCS Descriptor List field in the SCS Descriptor element identifies how MSDUs are classified and the priority to assign to MSDUs that match this classification. [0133] Each SCS stream is identified by an SCSID. This SCSID is used by a non-AP STA to request creation, modification, or deletion of an SCS stream. The SCSID is used by an AP to identify an SCS stream in SCS responses.

[0134] Upon receipt of an SCS Request frame from an associated non-AP STA, the AP shall respond with a corresponding SCS Response frame.

[0135] If the AP declines a request to change a previously accepted SCSID, the previously accepted classification for this SCSID continues to operate.

[0136] If the requested SCS is accepted by the AP, the AP shall process subsequent incoming individually addressed MSDUs from the DS or WM that match the TCLAS elements and optional TCLAS Processing element classifier specified in the SCS Descriptor element. [0137] If an MSDU matches the classifier specified in the SCS Descriptor elements of multiple SCS streams, the SCS Descriptor element that specifies the greatest number of classifier parameters required for a match (i.e., the most granular classifier) is used. If an MSDU matches the classifier specified in SCS Descriptor elements that specify the same number of classifier parameters, which classifier is used is implementation dependent.

[0138] If multiple TCLAS elements are included in an SCS Descriptor element, the number of classifier parameters required for a match is the sum of the number of classifier parameters required for a match for each TCLAS element if the Processing field in the TCLAS Processing element is 0, or is the minimum of the number of classifier parameters required for a match for each TCLAS element if the Processing field is 1. If a TCLAS Processing element is included where the Processing field is 2, the number of classifier parameters required for a match is 0.

[0139] A STA should not request creation of multiple SCS streams that might match the same MSDU and specify the same number of classifier parameters.

[0140] A non-AP STA may request the termination of an accepted SCS stream by sending an SCS Request frame with the Request Type field set to “Remove” and the requested SCSIDs in the SCS Descriptor element. Intra-Access Priority, TCLAS, or TCLAS Processing elements shall be included in the SCS Descriptor element.

[0141] Upon reception of an SCS Request frame that requests termination of an SCS stream, the AP shall send an SCS Response frame with the Dialog Token and SCSID fields set to the corresponding fields in the SCS Request frame and the Status field set to TCLAS_PROCESSING_TERMINATED.

[0142] The AP may use the MLME-SCS-TERM. request primitive to send an unsolicited SCS Response frame at any time to terminate an SCS stream. When an SCS stream is terminated, the AP shall cease to apply the classifier(s) related to it.

[0143] The SCS enables the establishment of a classification using layer 2 and/or layer 3 signaling to match incoming individually addressed MSDUs. Once classified, individually addressed MSDUs matching the classification are assigned to an access category and are tagged with their drop eligibility. When intra-access category prioritization is enabled, SCS allows MSDUs matching the classification to be assigned to the primary or alternate EDCA transmit queues so that finer grained prioritization can be applied.

[0144] Intra-access category prioritization provides six transmit queues that map to four enhanced distributed channel access functions (EDCAFs) to enable differentiation between traffic streams that are in the same access category in order for finer grained prioritization to be applied between individual AV streams or voice streams.

[0145] A multi-link device (MLD) is an entity capable of managing communication over multiple links. The MLD may be a logical entity and may have more than one affiliated station (STA) An MLD may be an access point MLD (AP MLD) where a STA affiliated with the MLD is an AP STA (or an AP). An MLD may be a non-access point MLD (non-AP MLD) where a STA affiliated with the MLD is a non-AP STA (or an STA).

[0146] Communication across different frequency bands/channels may occur simultaneously, or not, depending on the capabilities of both the communicating AP MLD and non-AP MLD. [0147] An MLD may have a single MAC service access point (MAC-SAP) to the LLC layer, which includes a MAC data service. The MLD may support multiple MAC sublayers, coordinated by a sublayer management entity (SME). Each AP STA (or non-AP STA) affiliated with an AP MLD (or non-AP MLD) has a different MAC address within the MLD.

[0148] The SME is responsible for coordinating the MAC sublayer management entities (MLMEs) of the affiliated STAs of the MLD to maintain a single robust security network association (RSNA) key management entity as well as a single IEEE 802.1X Authenticator or Supplicant for multi-link operation (MLO).

[0149] Multi-link operation (MLO) procedures allow a pair of MLDs to discover, synchronize, (de)authenticate, (re)associate, disassociate, and manage resources with each other on any common bands or channels that are supported by both MLDs. The Authenticator and the MAC-SAP of an AP MLD may be identified by the same AP MLD MAC address. The Supplicant and the MAC-SAP of a non-AP MLD may be identified by the same non-AP MLD MAC address.

[0150] FIG. 8 illustrates a non-High Throughput (non-HT) PPDU 810, a HT-Mixed Mode PPDU 820, and Very High Throughput (VHT) PPDU 830.

[0151] Non-HT PPDU 810 may be used by STAs conforming to the IEEE 802.11a standard amendment. As shown in FIG. 8, non-HT PPDU 810 includes a non-HT Short Training field (L-STF), a non-HT Long Training field (L-LTF), a non- HT Signal field (L-SIG), and a Data field. The L-STF, L-LTF, and L-SIG form a 20 pis preamble of non-HT PPDU 810.

[0152] The L-STF may be used by a receiver of non-HT PPDU 810 to synchronize with the carrier frequency and frame timing of a transmitter of non-HT PPDU 810 and to adjust the receiver signal gain. The L-LTF may be used by the receiver of non-HT PPDU 810 to estimate channel coefficients in order to equalize the channel response (e.g., amplitude and phase distortion) in both the L-SIG and the Data fields of non-HT PPDU 810.

[0153] The L-SIG contains parameters needed to demodulate the Data field, which contains a payload of non-HT PPDU 810. The L-SIG may be equalized using the channel coefficients estimated using the L-LTF and demodulated to obtain the demodulation parameters of the Data field. The Data Field includes one or more symbols each having a duration of 4 ps, where 3.2 pis carry symbol information and 0.8 pis carry a Guard Interval (Gl).

[0154] For non-HT PPDUs, the only supported bandwidth is 20 MHz, which is divided into 64 subcarriers. As such, non- HT PPDU 810 may be encoded using a subcarrier spacing of 20MHz/64 or 312.5kHz.

[0155] HT-Mixed Mode PPDU 820 may be used by STAs conforming to the IEEE 802.11n standard amendment. HT- Mixed Mode PPDU 820 can support MIMO to up to 4 spatial streams, which enhances spectral efficiency four folds. HT- Mixed Mode PPDU 820 has a minimum preamble duration of 35.6 ps, which may increase depending on the number of spatial streams carried by the PPDU.

[0156] As shown in FIG. 8, HT-Mixed Mode PPDU 820 includes an L-STF, an L-LTF, an L-SIG, an HT Signal field (HT- SIG) field, an HT Short Training field (HT-STF) field, one or more HT Long Training field (HT-LTF), and a Data field. The HT-LTF and Data fields include of one or more symbols each having a duration of 3.6 ps or 4 ps. In both cases, 3.2 ps carry symbol information while the remaining 0.4 ps or 0.8 ps carry a Gl. The 0.4 ps long Gl is called short Gl while the 0.8 ps long Gl is called regular or normal Gl. [0157] For HT-Mixed Mode PPDUs, two bandwidths, 20 MHz and 80 MHz, may be supported. When the PPDU bandwidth is 20MHz, the band is divided into 64 subcarriers. When the PPDU bandwidth is 80 MHz, the band is divided into 128 subcarriers. In both cases, subcarrier spacing of 312.5 kHz is maintained.

[0158] VHT PPDU 830 may be used by STAs conforming to the IEEE 802.11 ac standard amendment. VHT PPDU 830 can support MIMO to up to 8 spatial streams, which enhances spectral efficiency eight folds. VHT PPDU 830 has a minimum preamble duration of 39.6 ps, which may increase depending on the number of spatial streams carried by the VHT PPDU 830.

[0159] As shown in FIG. 8, VHT PPDU 830 includes an L-STF, an L-LTF, an L-SIG, a VHT Signal A field (VHT-SIG- A), a VHT Short Training field (VHT-STF), one or more VHT Long Training field (VHT-LTF), a VHT Signal B field (VHT- SIG-B) and a Data field. The VHT-LTF and data fields of VHT PPDU 830 include of one or more symbols each having a duration of 3.6 ps or 4 ps. In both cases, 3.2 ps carry symbol information while the remaining 0.4 ps or 0.8 ps carry of the Gl. The 0.4ps long Gl is called the short Gl while the 0.8ps long is called regular or normal Gl.

[0160] For VHT PPDUs, four bandwidths, 20 MHz, 80 MHz, 80 MHz, and 160 MHz, may be supported. When the PPDU bandwidth is 20MHz, the band is divided into 64 subcarriers. When the PPDU bandwidth is 40 MHz, the band is divided into 128 subcarriers. When the PPDU bandwidth is 80MHz, the band is divided into 256 subcarriers. When the PPDU bandwidth is 160 MHz, the band is divided into two 256-subcarrier 80 MHz bands. In all cases, a subcarrier spacing of 312.5 kHz is maintained.

[0161] FIG. 9 illustrates a High Efficiency (HE) Single User(SU) PPDU 910, an HE Multi-user (MU) PPDU 920, and an HE Extended Range (ER) SU PPDU 930. HE SU PPDU 910, HE MU PPDU 920, and HE ER SU PPDU 930 may be used by STAs conforming to the IEEE 802.11ax standard amendment.

[0162] HE SU PPDU 910 supports higher spectral efficiency compared to VHT PPDU 1430 due to increased subcarrier spacing and higher order modulation support. HE SU PPDU 910 has a minimum preamble duration of 44 s.

[0163] As shown in FIG. 9, HE SU PPDU 910 includes an L-STF, an L-LTF, an L-SIG, a Repeated L-SIG (RL-SIG), a High Efficiency (HE) Signal A field (HE-SIG-A), an HE Short Training field (HE-STF) field, one or more HE Long Training field (HE-LTF), a Data field, and a Packet extension (PE) field.

[0164] Similar to HE SU PPDU 910, HE MU PPDU 920 supports higher spectral efficiency compared to VHT PPDU 430. HE MU PPDU 920 also supports OFDMA. Due to denser subcarrier spacing (as in HE SU PPDU 910), HE MU PPDU 920 allows for payloads of multiple users to be multiplexed in the frequency domain in the data field. HE MU PPDU 920 supports multiplexing the payloads of up to 9 users in a single 20MHz band. HE MU PPDU 920 has a minimum preamble duration of 47.2 ps, which may increase depending on the number of spatial streams carried by the HE MU PPDU 920.

[0165] As shown in FIG. 9, HE MU PPDU 920 includes an L-STF, an L-LTF, an L-SIG, an RL-SIG, an HE-SIG-A, an HE Signal B Field (HE-SIG-B), an HE-STF field, one or more HE-LTF field, a Data field, and a PE field. It is noted that compared to HE SU PPDU 910, HE MU PPDU 920 further includes HE-SIG-B. HE-SIG-B contains indications per STA of RU allocations. A STA may use the indications in HE-SIG-B to locate its payload in HE MU PPDU 920. [0166] For HE SU PPDU 910 and HE MU PPDU 920, the Gl portion of the HE-LTF and data fields may be one of one of 0.8 pis, 1.6 pis, and 3.2 pis. An AP or STA may use a suitable Gl duration depending on the channel conditions or capability of the target STA or AP.

[0167] For both HE SU PPDU 910 and HE MU PPDU 920, the information portion of the HE-LTF may be one of 3.2 pis, 6.4 pis, or 12.8 pis. Depending on the information portion duration, a subcarrier spacing of the HE-LTF may be one of: 312.5kHz if the information potion is 3.2 pis, 156.25kHz if the information portion is 6.4 pis, and 78.125kHz if the information portion is 12.8 pis. Unlink the HE-LTF, the information portion of the Data field for both HE SU PPDU 910 and HE MU PPDU 920 is always 12.8 pis. Hence, a subcarrier spacing of the data field is always 78.125kHz corresponding to the duration of the information portion being 12.8 pis. When a 3.2 pis or 6.4 pis long HE-LTF is used by a transmitting STA to transmit HE SU PPDU 910 or HE MU PPDU 920, a receiving STA is required to interpolate the channel estimates to a subcarrier spacing resolution of 78.125kHz to match the subcarrier spacing of the Data field.

[0168] As shown in FIG. 9, HE ER SU PPDU 930 includes an L-STF, an L-LTF, an L-SIG, an RL-SIG, an HE-SIG-A, an HE-STF, one or more HE-LTF, a Data field, and a PE field. It is noted that compared to HE SU PPDU 910, HE ERSU PPDU 930 has an HE-SIG-A that is duplicated in the time domain (16 pis long instead of 8 pis long in HE SU PPDU 410). As such, both L-SIG (duplicated using RL-SIG) and HE-SIG-A are sent in duplicates, which allows a receiving STA to combine the two copies to increase the energy of the received signal. This results in an extended range of reception and increases transmission reliability between the transmitting STA and the receiving STA.

[0169] FIG. 10 illustrates an Extremely High Throughput (EHT) Multi-user (MU) PPDU 1000. EHT MU PPDU 1000 may be used by STAs conforming to the IEEE 802.11 be standard amendment. EHT MU PPDU 1000 supports OFDMA but up to a bandwidth of 320MHz. EHT MU PPDU 1000 further improves spectral efficiency due to a support of an even higher order modulation compared to other PPDUs (e.g., HE SU PPDU 910 and HE MU PPDU 920) while supporting the same number of spatial streams. EHT MU PPDU 1000 has a minimum preamble duration of 47.2 pis, which may increase depending on the number of spatial streams carried by the EHT MU PPDU 1000.

[0170] As shown in FIG. 10, EHT MU PPDU 1000 includes an L-STF, an L-LTF, an L-SIG, an RL-SIG, a Universal Signal field (U-SIG), an EHT Signal Field (EHT-SIG), an EHT Short Training Field (EHT-STF) field, one or more EHT Long Training field (EHT-LTF), a Data field, and a PE field. It is noted that according to the IEEE 802.11be standard amendment, EHT MU PPDU 1000 maybe used by a transmitting STA for both SU and MU transmissions.

[0171] The U-SIG is intended to ensure forward compatibility of EHT MU PPDU 1000. This means that any future PPDUs that are backward compatible to IEEE 802.11 be will contain the same U-SIG field and interpretation. Because of this, IEEE 802.11 be STAs will be able to understand at least in part a PPDU developed in a future amendment.

[0172] The EHT-SIG contains indications per STA of resource unit (RU) allocations. A STA may use the indications in the EHT-SIG to locate its payload in EHT MU PPDU 1000.

[0173] The Gl portion of the EHT-LTF and data fields of EHT MU PPDU 1000 may be one of: 0.8 pis, 1.6 pis, or 3.2 pis. An AP or STA may use a suitable Gl duration depending on the channel conditions or capability of the target STA or AP. [0174] The information portion of the EHT-LTF maybe one of 3.2 pis, 6.4 pis, or 12.8 pis. Depending on the information portion duration, a subcarrier spacing of the EHT-LTF may be one of: 312.5kHz if the information potion is 3.2 pis, 156.25kHz if the information portion is 6.4 pis, or 78.125kHz if the information portion is 128 pis. The information portion of the Data field of EHT MU PPDU 1000 is always 12.8 pis. Hence, a subcarrier spacing of the data field is always 78.125kHz corresponding to the duration of the information portion being 12.8 pis. When a 3.2 pis long or a 6.4 pis long EHT-LTF is used by a transmitting STA to transmit EHT MU PPDU 1000, a receiving STA is required to interpolate the channel estimates to a subcarrier spacing resolution of 78.125kHz to match the data field subcarrier spacing.

[0175] FIG. 11 illustrates an example multi-user request-to-send (MU-RTS) trigger frame 1100. MU-RTS trigger frame 1100 may be used by an AP to solicit simultaneous CTS frames from multiple STAs to transmit a downlink (DL) MU PPDU to the multiple STAs. As shown in FIG. 11, example MU-RTS trigger frame 1100 may comprise a frame control field, a duration field, a receiver address (RA) field, a transmitter address (TA) field, a common info field, a user info list field, a padding field, and/or frame check sequence (FCS) field. The frame control, TA, RA, padding, and FCS fields may be similar to the corresponding fields of trigger frame 500 described above. The duration field may be set to the time, in microseconds, required to transmit the DL MU PPDU, plus the time required to transmit one CTS frame, one ACK frame (if required), and three SIFS periods.

[0176] In an example, the common info field may be a high-efficiency (HE) variant common info field or an extremely high throughput (EHT) variant common info field. An EHT variant common info field may comprise, as shown in FIG. 11, one or more of the following subfields: trigger type, UL length, more TF, CS required, UL BW, Gl and HE/EHT-LTF Type/Triggered TXOP sharing mode, number of HE/EHT-LTF symbols, LDPC extra symbol segment, AP Tx Power, Pre- FEC padding factor, PE disambiguity, UL spatial reuse, HE/EHT P160, special user info field flag, EHT reserved, reserved, or trigger dependent common info.

[0177] The trigger type subfield indicates that frame 1100 is an MU-RTS trigger frame.

[0178] The Gl and HE/EHT-LTF Type/Triggered TXOP sharing mode subfield may include a triggered TXOP sharing mode subfield. In an example, the triggered TXOP sharing mode subfield may be set to a zero value indicating the MU- RTS that does not initiate TXS procedure. In an example, the triggered TXOP sharing mode subfield may be set to a non-zero value (e.g., 1 or 2). In an example, the triggered TXOP sharing mode subfield may be set to 1. As such, the triggered TXOP sharing mode subfield may indicate that a STA indicated by an AID12 subfield of a user info field (of the user info list field) may transmit one or more non-TB PPDUs to the AP during a time indicated in the allocation duration subfield of the user info field. In another example, the triggered TXOP sharing mode subfield may be set to 2. As such, the triggered TXOP sharing mode subfield may indicate that a STA indicated by an AID12 subfield of a user info field (of the user info list field) may transmit one or more non-TB PPDUs to the AP or to a peer STA during the time indicated by the allocation duration subfield of the user info field. In an example, the peer STA may be a STA with a connection for P2P communication or direct communication with the STA. [0179] The user info list field may include one or more user info fields. In an example, an EHT variant user info field may comprise, as shown in FIG. 11, one or more of the following subfields: AID12, RU allocation, allocation duration, reserved, or PS160.

[0180] The AID12 subfield may indicate an association identifier (AID) of a STA that may use a time indicated by the allocation duration subfield.

[0181] The RU allocation subfield may indicate the location and size of the RU allocated for a STA indicated by the AID12 subfield.

[0182] The allocation duration subfield may indicate a time allocated by an AP transmitting MRTT frame 1100. The allocated time may be a portion a TXOP obtained by the AP.

[0183] FIG. 12 illustrates an example block acknowledgment request (BlockAckReq or BAR) frame 1200. As shown in FIG. 12, example BAR frame 1200 may comprise a frame control field, a duration field, a receiver address (RA) field, a transmitter address (TA) field, a BAR control field, a BAR information field, and/or frame check sequence (FCS) field.

[0184] The frame control and FCS fields may be similar to the corresponding fields of trigger frame 500 described above.

[0185] The Duration/ID field is set to the estimated time required to transmit.

[0186] one Ack or BlockAck frame, as applicable, plus one SIFS

[0187] The RA field indicates the address of a recipient STA of BAR frame 1200.

[0188] The TA field indicates the address of a STA transmitting BAR frame 1200 ora bandwidth signaling TA.

[0189] The BAR control field includes a first reserved subfield, a BAR type subfield, a second reserved subfield, and a TIDJNFO subfield.

[0190] The BAR type subfield of the BAR control field indicates a frame variant of BAR frame 1200. For example, the BAR type subfield set to 1 indicates an extended compressed BlockAckReq frame variant. The BAR type subfield set to 2 indicates a compressed BlockAckReq frame variant. The BAR type subfield set to 3 indicates a multi-TID BlockAckReq frame variant. The BAR type subfield set to 6 indicates a groupcast with retries (GCR) BlockAckReq frame variant. The BAR type subfield set to 10 indicates a general link groupcast with retries (GLK-GCR) BlockAckReq frame variant. The values 0, 4-5, 7-9, and 11-15 are currently reserved.

[0191] The meaning of the TID_INFO subfield of the BAR Control field depends on the BlockAckReq frame variant type indicated by the BAR type subfield. For example, the TIDJ NFO subfield of the BAR Control field of the Compressed BlockAckReq frame contains the TID for which a BlockAck frame is requested.

[0192] The meaning of the BAR Information field of the BlockAckReq frame depends on the BlockAckReq frame variant type. For example, the BAR Information field of the Compressed BlockAckReq frame contains a Block Ack Starting Sequence Control subfield.

[0193] FIG. 13 illustrates an example 1300 of a power save (PS) mode. As shown in FIG. 13, example 1300 includes STAs 1302 and 1304. STAs 1302 and 1304 may each be an AP STA or a non-AP STA. It is assumed that STA 1304 implements the PS mode illustrated in FIG. 13, which may be denoted as a dynamic PS mode or a low power listening (LPL) mode.

[0194] In an implementation, a STA (AP STAor non-AP STA) implementing the PS mode illustrated in FIG. 13 may be in a first power state/mode of the PS mode or in a second power state/mode of the PS mode. The first power state/mode may be referred to as a lower capability state/mode a lower power receive state/mode or a listen/listening state/mode. The second power state/mode may be referred to as a higher capability state/mode, a higher power receive state/mode or an awake state/mode. While in the first power state/mode, the STA is capable of receiving PPDUs of a first category. While in the second power state/mode, the STA is capable of receiving PPDUs of the first category and PPDUs of a second category. In an implementation, the STA is not capable of receiving PPDUs of the second category during the first power state/mode. In an implementation, the STA is capable of receiving PPDUs of only the first category during the first power state/mode.

[0195] In an implementation, the first category may include PPDUs having a non-HT PPDU format such as non-HT PPDU 810 described above. In another implementation, the first category may include, additionally or alternatively, PPDUs having a data rate that is less than or equal to 24 Mbps, a bandwidth of 20 MHz, and/or a single spatial stream. The second category may include PPDUs having a format other than the non-HT PPDU format. For example, the second category may include PPDUs having a high throughput (HT) format, such as HT Mixed Mode PPDU 820, a VHT format such as VHT PPDU 830, an HE PPDU such as HE SU PPDU 910, HE MU PPDU 920, or HE ER SU PPDU 930, an EHT PPDU such as EHT MU PPDU 1000, an ultra-high reliability (UHR) PPDU, or a physical layer version identifier field. Additionally, or alternatively, the second category may include PPDUs having a data rate that is greater than 24 Mbps, a bandwidth greater than 20 MHz, and/or a plurality of spatial streams.

[0196] The STA may transition between the first power state/mode and the second power state/mode of the PS. In an implementation, to reduce the power consumption of the STA, the first power state/mode may correspond to a default state/mode of the PS mode. As such, the STA may operate in the first power state/mode and may transition to the second power state/mode as needed.

[0197] In an implementation, as illustrated in example 1300, the STA may transition from the first power state/mode to the second power state/mode in response to being solicited by another STA. For example, as shown in FIG. 13, STA 1304, which implements the PS mode, may operate in the first power state/mode and may transition to the second power state/mode in response to a solicitation from STA 1302. Specifically, STA 1302 may transmit an initial control frame (ICF) 1306 to STA 1304 requesting that STA 1304 transition from the first power state/mode to the second power state/mode of the PS mode. STA 1302 may request that STA 1304 transition from the first power state/mode to the second power state/mode in order to transmit to STA 1304 a PPDU 1310 of the second category that STA 1304 is not capable of receiving during the first power state/mode (e.g., an EHT PPDU, a PPDU having a bandwidth greater than 20 MHz, and/or a PPDU having multiple spatial streams). In an implementation, ICF 1306 may be a request to send (RTS) frame, a multiuser RTS (MU-RTS) frame or a BlockAck Request (BAR) frame. ICF 1306 may be carried in a PPDU of the first category. In an implementation, ICF 1306 may be carried in a PPDU using a non-HT duplicate format with a bandwidth of 40 MHz, 80 MHz, 160 MHz or 320 MHz. In an implementation, ICF 1306 may include signaling indicating the PPDU bandwidth. [0198] On receiving ICF 1306, STA 1304 initiates a transition from the first power state/mode to the second power state/mode. For example, on receiving ICF 1306, STA 1304 may enable/poweron receiver capabilities needed to receive the PPDU of the second category that STA 1302 wishes to transmit to STA 1304. The transition from the first power state/mode to the second power state/mode may be associated with a state/mode transition duration. The state/mode transition duration may depend on the processing capabilities of STA 1304. In an implementation, STA 1302 may include padding in ICF 1306 to allow STA 1304 to transition from the first power state/mode to the second power state/mode in a timely manner. Hence, as shown in FIG. 13, STA 1304 may start the state/mode transition before the reception of ICF 1306 is completed (i.e. without decoding the padding information).

[0199] In an implementation, STA 1304 responds to ICF 1306 by transmitting an initial control response (ICR) 1308 to STA 1302. ICR 1308 informs STA 1302 that STA 1304 is transitioning from the first power state/mode to the second power state/mode. In an implementation, as shown in FIG. 13, STA 1304 may transmit ICR 1308 while transitioning from the first power state/mode to the second power state/mode. In an implementation, STA 1304 may transmit ICR 1308 after completing the transition from the first power state/mode to the second power state/mode. Completing the transition before transmitting ICR 1308 may enable STA 1304 to perform clear channel assessment over a bandwidth that is higher than 20 MHz. This may enable STA 1304 to transmit ICR 1308 on idle channels with bandwidths higher than 20 MHz, which improves hidden node protection due to the transmission of ICR 1308. In another implementation, STA 1304 may transmit ICR 1308 before completing the transition to the second power state/mode. In such an implementation, STA 1304 may only be able to transmit ICR 1308 using a bandwidth of 20 MHz. ICR 1308 may be carried in a PPDU of the first category or the second category. In an implementation, STA 1304 transmits ICR 1308 a short interframe space (SIFS) after receiving ICF 1306.

[0200] On receiving ICR 1308, STA 1302 initiates transmission of PPDU 1310. In an implementation, STA 1302 transmits PPDU 1310 a SIFS after receiving ICR 1308. In an implementation, STA 1302 may begin transmitting PPDU 1310 while STA 1304 is still transitioning from the first power state/mode to the second power state/mode. PPDU 1310 may thus include a first PPDU part 1314 of the first category and a second PPDU part 1316 of the second category. In another implementation, STA 1302 may begin transmitting PPDU 1310 after STA 1304 has transitioned to the second power state/mode. PPDU 1310 may thus be entirely of the second category.

[0201] After receiving PPDU 1310, STA 1304 may transmit a BA frame 1312 to STA 1302. In an implementation, STA 1304 may return to the first power state/mode after receiving PPDU 1310. STA 1304 may transmit BA frame 1312 while in the second power state/mode or after returning to the first power state/mode.

[0202] FIG. 14 illustrates an example 1400 of an AP implementation of the PS mode illustrated in FIG. 13. As shown in FIG. 14, example 1400 includes an AP 1402 and a STA 1404. STA 1404 may be associated with AP 1402. It is assumed that AP 1402 implements the PS mode illustrated in FIG. 13. Specifically, as described above, while in the first power state/mode of the PS mode, AP 1402 is capable of receiving PPDUs of a first category; and while in the second power state/mode of the PS mode, AP 1402 is capable of receiving PPDUs of the first category and PPDUs of a second category. The first category and the second category may be as described above with reference to FIG. 13.

[0203] In an implementation, while in the first power state/mode, AP 1402 is capable of receiving data frames carried by PPDUs of the first category. In another implementation, AP 1402 is capable of receiving PPDUs of the first category while in the first power state/mode, AP 1402 is not capable of receiving the data frames carried by PPDUs of the first category while in the first power state/mode. In an implementation, while in the second power state/mode, AP 1402 is capable of receiving data frames carried by PPDUs of the first category or the second category.

[0204] Additionally, AP 1402 may support another mode of operation. The other mode may correspond to an active mode or to a power saving mode different than the PS mode illustrated in FIG. 13. The other mode may have one or more power states. AP 1402 may be capable of receiving PPDUs of the first category and/or of the second category in any power state/mode.

[0205] In an implementation, AP 1402 maybe configured to announce a time period during which AP 1402 will operate in the PS mode. For example, as shown in FIG. 14, during a first time period, AP 1402 may transmit a frame 1406 indicating or announcing a second time period during which AP 1402 will operate in the PS. The second time period may or may not be adjacent to the first time period. In an implementation, AP 1402 may be operating in the other mode during the first time period. In another implementation, AP 1402 may be operating in the PS mode during the first time period. Frame 1406 may indicate a start time T1 and an end time T2 of the second time period. Alternatively, frame 1406 may indicate a start time T1 and a duration of the second time period.

[0206] In an example, as shown in FIG. 14, AP 1402 may be in the other mode before switching to the PS mode at the beginning of the second time period. In an implementation, AP 1402 may be configured, upon switching to the PS mode from the other mode, to operate in a default state/mode of the PS mode. In an implementation, the default state/mode may be the first power state/mode as described above. In another example, not shown in FIG. 14, AP 1402 be in the second power state/mode of the PS mode before the beginning of the second time period. AP 1402 may switch from the second power state/mode to the first power state/mode of the PS mode at the beginning of the second time period.

[0207] In an implementation, as illustrated in example 1400, AP 1402 may transition from the first power state/mode to the second power state/mode in response to being solicited by a STA. For example, as shown in FIG. 14, after switching to the PS mode at the beginning of the second time period, AP 1402 may operate in the first power state/mode. Subsequently, AP 1402 receives an ICF 1408 requesting that AP 1402 transition from the first power state/mode to the second power state/mode to receive from STA 1404 a PPDU 1412 of the second category. On receiving ICF 1408 from STA 1404, AP 1402 may respond with an ICR 1410 and may initiate a transition from the first power state/mode to the second power state/mode.

[0208] In an implementation, AP 1402 may determine, from ICF 1408, a TXOP duration, a bandwidth, and/or a modulation and coding scheme (MCS) of PPDU 1412. AP 1402 may turn on/enable receiver capabilities based on the bandwidth and MCS indicated in ICF 1408. In an implementation, AP 1402 may use the TXOP duration and the bandwidth indicated in ICF 1408 to reserve a suitable channel for PPDU 1412. For example, PPDU 1412 may have a bandwidth of 80 MHz and AP 1402 may reserve a primary 80 MHz channel for PPDU 1412. In an implementation, AP 1402 may perform a clear channel assessment (CCA) procedure over the channel to be used by STA 1404 for the transmission of PPDU 1412. After a successful CCA procedure, AP 1402 may transmit an ICR 1410 to STA 1404. ICR 1410 may be configured to reserve the channel to be used by STA 1404 for the transmission of PPDU 1412. In an implementation, ICR 1410 may be a clear to send (CTS) frame that indicates the channel to be used by STA 1404 for the transmission of PPDU 1412.

[0209] On receiving ICR 1410, STA 1404 initiates transmission of PPDU 1412. In an implementation, STA 1404 transmits PPDU 1412 a SIPS after receiving ICR 1410. After receiving PPDU 1412, AP 1402 may transmit a BA frame 1414 to STA 1404. In an implementation, AP 1402 may return to the first power state/mode after receiving PPDU 1412. AP 1402 may transmit BA frame 1414 while in the second power state/mode or after returning to the first power state/mode. After the second time period, AP 1402 may transition to the other mode of operation or may remain in the first power state/mode of the PS mode.

[0210] FIG. 15 illustrates an example 1500 that highlights a problem that may arise in association with the power save mode illustrated in FIG. 14. As shown in FIG. 15, example 1500 may include an AP 1502 and a STA 1504. STA 1504 may be associated with AP 1502.

[0211] It is assumed that AP 1502 supports the PS mode illustrated in FIG. 13. Specifically, as described above, while in the first power state/mode of the PS mode, AP 1502 is capable of receiving PPDUs of a first category; and while in the second power state/mode of the PS mode, AP 1502 is capable of receiving PPDUs of the first category and PPDUs of a second category. The first category and the second category may be as described above with reference to FIG. 13.

[0212] In an implementation, while in the first power state/mode, AP 1502 is capable of receiving data frames carried by PPDUs of the first category. In another implementation, while AP 1502 is capable of receiving PPDUs of the first category while in the first power state/mode, AP 1502 is not capable of receiving data frames carried by PPDUs of the first category while in the first power state/mode. In an implementation, while in the second power state/mode, AP 1502 is capable of receiving data frames carried by PPDUs of the first category or the second category.

[0213] Additionally, AP 1502 may support another mode of operation. The other mode may correspond to an active mode or to a power saving mode different than the PS mode illustrated in FIG. 13. The other mode may have one or more power states. AP 1502 may be capable of receiving PPDUs of the first category and/or of the second category in any power state/mode.

[0214] In an example, PPDUs of the first category and PPDUs of the second category may carry data frames comprising traffic of a first traffic type and/or traffic of a second traffic type. In an implementation, the first traffic type may comprise low latency traffic or high-reliability traffic. In an implementation, the first traffic type may comprise a first access category. For example, the first access category may be associated with video (AC_VI) or voice (AC_VO). In an implementation, the second traffic type may be different from the first traffic type. In an implementation, the second traffic type may comprise a second access category that is different from the first access category. [0215] In an implementation, AP 1502 may reserve the second power state/mode for receiving data frames comprising traffic of the first traffic type. For example, the second power state/mode may correspond to a higher capability state/mode, a higher power receive state/mode with higher receive capabilities than the first power state/mode. For various reasons, it may be required that traffic of the first traffic type be received by AP 1502 while in the second power state/mode. For example, in an implementation, traffic of the first traffic type may require low-latency, high-reliability, and/or high throughput. In an implementation, traffic of the first traffic type may include voice or video streams.

[0216] As shown in FIG. 15, example 1500 may begin with AP 1502 transmitting a frame 1506, using EDCA, during a first time period. In an example, frame 1506 may comprise capability information of AP 1502 indicating support by AP 1502 of the PS mode illustrated in FIG. 13. Frame 1506 may comprise a beacon frame. In an example, frame 1506 may announce that AP 1502 is operating in the PS mode. In an implementation, AP 1502 may be operating in a default state/mode of the PS mode during the first time period. In an implementation, the default state/mode may be the first power state/mode as described above. STA 1504 may receive frame 1506 and may determine AP 1502 is operating in the PS mode.

[0217] As shown in FIG. 15, in an example, during the first time period, data may arrive at STA 1504 for transmission to AP 1502. In an example, the data may comprise traffic of the second traffic type.

[0218] In an implementation, as illustrated in example 1500, AP 1502 may transition from the first power state/mode to the second power state/mode in response to being solicited by a STA. For example, AP 1502 receives an ICF 1508 from STA 1504 requesting that AP 1502 transition from the first power state/mode to the second power state/mode to receive from STA 1504 a PPDU of the second category.

[0219] On receiving ICF 1508 from STA 1504, AP 1502 may respond with an ICR 1510 and may initiate a transition from the first power state/mode to the second power state/mode at a time T1. In an example, the first time period may end at time T1. In an implementation, AP operates in the second power state/mode during a second time period. In an example, the second time period may begin at time T 1.

[0220] On receiving ICR 1510, STA 1504 initiates transmission of the PPDU of the second category. In an example, the PPDU may comprise an MPDU 1512-1 comprising the traffic of the second traffic type. In an example, the PPDU may further comprise an MPDU 1512-2 aggregated to MPDU 1512-1. As shown in FIG. 15, MPDUs 1512-1 and 1512-2 may comprise traffic of the second traffic type. In another example (now shown in FIG. 15), MPDU 1512-2 maybe carried in another PPDU transmitted from STA 1504 to AP 1502.

[0221] In an implementation, STA 1504 transmits the PPDU of the second category a SIFS after receiving ICR 1510. After receiving the PPDU, AP 1502 may transmit a BA frame 1514 to STA 1504. In an implementation, AP 1502 may return to the first power state/mode at a time T2 after receiving the PPDU. AP 1502 may transmit BA frame 1514 while in the second power state/mode or after returning to the first power state/mode. In an example, the second time period may end at time T2.

[0222] As shown in FIG. 15, in response to ICF 1508, AP 1502 transitions from the first power state/mode to the second power state/mode, which may be a high power receive state, only to receive traffic of the second traffic type. However, based on the access category of the second traffic type, the reception by AP 1502 of traffic of the second traffic type while operating in the second power state/mode may be power inefficient. For example, the second traffic type may correspond to non-low latency traffic which can wait for AP 1502 to return to the first power state/mode to receive it. As a result, despite implementing the PS mode described above, AP 1502 may operate in a manner that results in an unnecessarily high power consumption for the type of traffic being received byAP 1502.

[0223] Embodiments of the present disclosure, as further described below, address the above-described problems of existing power save procedures. In an aspect, a first STA may transmit to a second STA a first frame indicating a first traffic type that the second STA is allowed to transmit to the first STA while the first STA operates in a first power state/mode of a power save mode. The first traffic type may comprise low latency traffic or high reliability traffic. The first traffic type may comprise a first traffic identifier (TID), a first traffic category (T C), a first traffic stream (TS), a first access category (AC), a first stream classification service (SCS) stream, or a first stream classification service identifier (SCSID). The power save mode may comprise a dynamic PS mode or a low-power listening (LPL) mode, for example. The first power state/mode may be a high power receive state/mode or an awake state, for example. While in the first power state/mode, the first AP may be capable of receiving PPDUs of a first category and PPDUs of a second category. The first STA may receive from the second STA and while the first STA operates in a second power state/mode of the power save mode, a second frame. The second power state/mode may be a lower power receive state/mode or a listen/listening state, for example. While in the second power state/mode, the first AP may be capable of receiving PPDUs of a first category. The first STA may transition and in response to the second frame, from the second power state/mode to the first power state/mode. The first STA may receive from the second STA and while the first STA operates in the first power state/mode, a third frame comprising one or more first data frames of the first traffic type. As such, while the first STA operates in the first power state/mode of the power save mode, the second STA may send to the first STA only data frames of the first traffic type. Power consumption of the first STA may thus be reduced by limiting operation in the first power state/mode to receive certain traffic types, such as low latency traffic or high reliability traffic, for example.

[0224] FIG. 16 illustrates an example 1600 of a PS mode procedure according to an embodiment. Example 1600 is provided for the purpose of illustration only and is not limiting. As shown in FIG. 16, example 1600 may include a STA 1602 and a STA 1604. STA 1602 may comprise an AP STA. STA 1604 may comprise a non-AP STA associated with STA 1602. STA 1602 and STA 1604 may each comprise a multi-link device (MLD).

[0225] It is assumed in example 1600 that STA 1602 implements the power save (PS) mode illustrated in FIG. 16, which may be denoted as a dynamic PS mode or a low power listening (LPL) mode.

[0226] In an implementation, STA 1602 implementing the PS mode illustrated in FIG 16 may be in a first power state/mode of the PS mode or in a second power state/mode of the PS mode. The first power state/mode may be referred to as lower capability state/mode, a lower power receive state/mode or a listen/listening state/mode. The second power state/mode may be referred to as a higher capability state/mode, a higher power receive state/mode or an awake state/mode. While in the first power state/mode, STA 1602 is capable of receiving PPDUs of a first category. While in the second power state/mode, STA 1602 is capable of receiving PPDUs of the first category and PPDUs of a second category. In an implementation, STA 1602 is not capable of receiving PPDUs of the second category during the first power state/mode. In an implementation, STA 1602 is capable of receiving PPDUs of only the first category during the first power state/mode.

[0227] In an implementation, the first category may include PPDUs having a non-HT PPDU format such as non-HT PPDU 810 described above. In another implementation, the first category may include, additionally or alternatively, PPDUs having a data rate that is less than or equal to 24 Mbps, a bandwidth of 20 MHz, and/or a single spatial stream. The second category may include PPDUs having a format other than the non-HT PPDU format. For example, the second category may include PPDUs having a high throughput (HT) format such as HT mixed mode PPDU 820, a VHT format such as VHT PPDU 830, an HE PPDU such as HE SU PPDU 910, HE MU PPDU 920, or HE ER SU PPDU 930, an EHT PPDU such as EHT MU PPDU 1000, an ultra-high reliability (UHR) PPDU, or a physical layer version identifier field. Additionally, or alternatively, the second category may include PPDUs having a data rate that is greater than 24 Mbps, a bandwidth greater than 20 MHz, and/or a plurality of spatial streams.

[0228] STA 1602 may transition between the first power state/mode and the second power state/mode of the PS mode. In an implementation, to reduce the power consumption of the STA, the first power state/mode may correspond to a default state/mode of the PS mode. As such, the STA may operate in the first power state/mode and may transition to the second power state/mode as needed.

[0229] Similar to AP 1402 described in FIG. 14, STA 1602 may support another mode of operation. The other mode may correspond to an active mode or to a power saving mode different than the PS mode illustrated in FIG. 16. The other mode may have one or more power states. STA 1602 may be capable of receiving PPDUs of the first category and/or of the second category in any power state/mode of the other mode.

[0230] In an embodiment, PPDUs of the first category and PPDUs of the second category may carry data frames comprising traffic of a first traffic type and traffic of a second traffic type.

[0231] In an embodiment, the first traffic type may comprise low latency traffic or high-reliability traffic. In an embodiment, the first traffic type may comprise a first traffic identifier (TID). In an embodiment, the first traffic type may comprise a first traffic category (TC) or a first traffic stream (TS). In an embodiment, the first traffic type may comprise a first access category (AC). For example, the first AC may be associated with video (AC_VI) or voice (AC_VO). In another embodiment, the first traffic type may comprise a first stream classification service (SCS) stream. In another embodiment, the first traffic type may comprise a first SCS identifier (SCSID).

[0232] In an embodiment, the second traffic type may be different from the first traffic type. In an embodiment, the second traffic type may comprise a second TID. The second TID may be different from the first TID In an embodiment, the second traffic type may comprise a second TC or a second TS. The second TC may be different from the first TC. The second TS may be different from the first TS. In an embodiment, the second traffic type may comprise a second AC. The second AC may be different from the first AC. In another embodiment, the second traffic type may comprise a second SCS stream. The second SCS stream may be different from the first SCS stream. In another embodiment, the second traffic type may comprise a second SCSID. The second SCSID may be different from the first SCSID. [0233] In an implementation, while in the first power state/mode, STA 1602 is capable of receiving data frames carried by PPDUs of the first category. In an embodiment, STA 1602 may be capable of receiving traffic of the first traffic type and/or traffic of the second traffic type while operating in the first power state/mode. In an implementation, while STA 1602 operates in the first power state/mode, data frames carried by PPDUs of the first category may comprise traffic of the first traffic type or traffic of the second traffic type.

[0234] In another implementation, while in the first power state/mode, STA 1602 is not capable of receiving the data frames carried by PPDUs of the first category. In an embodiment, STA 1602 may not be capable of receiving traffic of the first traffic type or traffic of the second traffic type while operating in the first power state/mode. In an implementation, while STA 1602 operates in the first power state/mode, data frames carried by PPDUs of the first category may comprise traffic of the first traffic type or traffic of the second traffic type.

[0235] In an implementation, while in the second power state/mode, STA 1602 is capable of receiving data frames carried by PPDUs of the first category or the second category. In an embodiment, STA 1602 may be capable of receiving traffic of the first traffic type while operating in the second power state/mode. In an implementation, while STA 1602 operates in the second power state/mode, data frames carried by PPDUs of the first category or the second category may comprise traffic of the first traffic type. In another embodiment, STA 1602 may be capable of receiving traffic of the second traffic type while operating in the second power state/mode. In an implementation, while STA 1602 operates in the second power state/mode, data frames carried by PPDUs of the first category or the second category may comprise traffic of the second traffic type.

[0236] In an embodiment, before example 1600 begins, STA 1604 may initiate an SCS procedure with STA 1602. In an example, STA 1604 may transmit to STA 1602 an SCS request frame indicating the first SCSID (associated with traffic of the first traffic type). In an example, the SCS request frame may further indicate the second SCSID (associated with traffic of the second traffic type). In response, STA 1604 may receive an SCS response frame from STA 1604 indicating a first value associated with the first SCSI D. In an example, the SCS response frame may further indicate a second value associated with the second SCSID.

[0237] In an embodiment, STA 1602 may be configured to reserve the second power state/mode for receiving data frames comprising traffic of the first traffic type. This capability, in conjunction with the PS mode described above, may provide a PS mode with traffic type awareness capability. For example, the second power state/mode may correspond to a higher capability state/mode, a higher power receive state/mode with higher receive capabilities than the first power state/mode. For various reasons, it may be required that traffic of the first traffic type be received by AP 1502 while in the second power state/mode For example, in an implementation, traffic of the first traffic type may require low-latency, high- reliability, and/or high throughput. In an implementation, traffic of the first traffic type may include voice or video streams. [0238] It is assumed in example 1600 that STA 1602 supports the PS mode with traffic type awareness capability. STA 1602 supporting the PS mode with traffic type awareness capability may include STA 1602 having the capability to transmit to another STA a first frame (such as frame 1606 described below) indicating a first traffic type that the other STA is allowed to transmit to STA 1602 while STA 1602 operates in the second power state/mode. STA 1602 supporting the PS mode with traffic type awareness capability may further include STA 1602 having the capability to receive from the other STA and while STA 1602 operates in the first power state/mode of the PS mode, a second frame (such as frame 1608 described below). STA 1602 supporting the PS mode with traffic type awareness capability may further include STA 1602 having the capability to transition between the first power state/mode and the second power state/mode. STA 1602 supporting the PS mode with traffic type awareness capability may further include STA 1602 having the capability to receive from the other STA and while STA 1602 operates in the second power state/mode, a third frame comprising one or more first data frames of the first traffic type (such as MPDUs 1612-1 , 1612-2 described below). [0239] It is also assumed in example 1600 that STA 1604 supports the PS mode with traffic type awareness capability. STA 1604 supporting the PS mode with traffic type awareness capability may include STA 1604 having the capability to receive from another STA the first frame (such as frame 1606 described below) indicating a first traffic type that STA 1604 is allowed to transmit to the other STA while the other STA operates in the second power state/mode of the PS mode. STA 1604 supporting the PS mode with traffic type awareness capability may further include STA 1604 having the capability to receive from the other STA and while the other STA operates in the second power state/mode, the third frame comprising one or more first data frames of the first traffic type (such as MPDUs 1612-1, 1612-2 described below). [0240] As shown in FIG. 16, the procedure illustrated in example 1600 may begin with STA 1602 transmitting a frame 1606 using EDCA during a first time period. In an embodiment, frame 1606 may indicate a traffic type that STA 1604 is allowed to transmit to STA 1602 while STA 1602 operates in the second power state/mode. In an embodiment, the traffic type that STA 1604 is allowed to transmit may comprise the first traffic type as described above.

[0241] In an embodiment, STA 1604 may be allowed to transmit a first stream of frames of the first traffic type to STA 1602 while STA 1602 operates in the second power state/mode, on condition that the first stream of frames satisfies a first condition.

[0242] In an embodiment, the first condition may comprise a first transmission duration of the first stream of frames being shorter than a first pre-determined duration. For example, the first pre-determined duration may be 100 ps or 1 ,000 ps. In another embodiment, the first condition may comprise a first transmission duration of the first stream of frames being longer than a second pre-determined duration. For example, the second pre-determined duration may be 100 ps or 1,000 ps.

[0243] In an embodiment, the first condition may comprise a first number of octets/bytes/bits of the first stream of frames being lower than a first pre-determined number of octets/bytes/bits. For example, the first pre-determined number may be 100 bytes or 1 ,000 bytes. In an embodiment, the first condition may comprise a first number of octets/bytes/bits of the first stream of frames being higher than a second pre-determined number of octets/bytes/bits. For example, the second pre-determined number may be 100 bytes or 1,000 bytes.

[0244] In an embodiment, the first condition may comprise a first queue size of buffer status report (BSR) information of the first steam of frames being smaller than a first pre-determined queue size of BSR information. The first predetermined queue size of BSR information may indicate an amount of buffered traffic, in units of octets. In an embodiment, the first condition may comprise a first queue size of BSR information of the first steam of frames being larger than a second pre-determined queue size of BSR information. The second pre-determined queue size of BSR information may indicate an amount of buffered traffic, in units of octets.

[0245] In an embodiment, the first condition may be indicated in frame 1606. In an embodiment, the first condition may comprise a dynamic condition (e.g., that may vary over time). The first condition may thus be repeatedly signaled by STA 1602. In another embodiment, the first condition may be a static condition (e.g., that does not vary over the time). The first condition may thus be signaled only once by STA 1602 or may be pre-configured in STA 1602 and STA 1604.

[0246] In an embodiment, frame 1606 may further indicate a traffic type that STA 1604 is not allowed to transmit to STA 1602 while STA 1602 operates in the second power state/mode. In an embodiment, the traffic type that STA 1604 is not allowed to transmit may comprise the second traffic type as described above.

[0247] In an embodiment, frame 1606 may comprise capability information of STA 1602 indicating support by STA 1602 of the PS mode with traffic type awareness illustrated in FIG. 16. In an embodiment, frame 1606 may announce that STA 1602 is operating in the PS mode with traffic type awareness. In an embodiment, STA 1602 may be operating in a default state/mode of the PS mode during the first time period. In an embodiment, the default state/mode may be the first power state/mode as described above. In another embodiment (not shown in FIG. 16), STA 1602 may operate in the other mode or in the second power state/mode of the PS mode and may transmit frame 1606 announcing that STA 1602 will operate in the PS mode in a future time period.

[0248] In an embodiment, frame 1606 may comprise a management frame indicating a broadcast address. In an example, frame 1606 may comprise a beacon frame. In another example, frame 1606 may comprise an action frame.

[0249] STA 1604 may receive frame 1606 and may determine that STA 1602 is operating in the PS mode. As shown in FIG. 16, during the first time period, data may arrive at STA 1604 for transmission to STA 1602. In an example, the data may comprise traffic of the first traffic type and traffic of the second traffic type.

[0250] Based on receiving frame 1606, STA 1604 may match traffic of the first traffic type buffered at STA 1604 to the first traffic type indicated in frame 1606. In an example, traffic of the first traffic type may be buffered in a queue associated with the first traffic category, the first traffic stream, the first access category, or the first SCS stream. In an embodiment, STA 1604 may prepare to transmit to STA 1602 a first stream of frames of the first traffic type when STA 1602 transitions to the second power state/mode. The first stream of frames may comprise one or more first data frames (such as a MPDUs 1612-1 and 1612-2) carrying traffic of the first traffic type.

[0251] In an embodiment, where transmission of the first stream of frames to STA 1602 is subject to the first stream of frames satisfying the first condition, STA 1604 may determine whether the first stream of frames satisfies the first condition.

[0252] In an embodiment, wherein the first condition is based on transmission duration, STA 1604 may determine whether a first transmission duration of the first stream of frames is shorter than a first pre-determined duration. In another embodiment, STA 1604 may determine whether a first transmission duration of the first stream of frames is longer than a second pre-determined duration. In an embodiment, the first transmission duration of the first stream of frames may correspond to a combined transmission duration of the one or more first data frames (e.g., MPDUs 1612-1 and 1612-2). [0253] In another embodiment, wherein the first condition is based on transmission size, STA 1604 may determine whether a first number of octets/bytes/bits of the first stream of frames is lower than a first pre-determined number of octets/bytes/bits In another embodiment, STA 1604 maydetermine whether a first number of octets/bytes/bits of the first stream of frames is higher than a second pre-determined number of octets/bytes/bits. In an embodiment, the first number of octets/bytes/bits of the first stream of frames may correspond to a total number of octets/bytes/bits of the one or more first data frames (e.g., MPDUs 1612-1 and 1612-2).

[0254] In another embodiment, wherein the first condition is based on queue size of BSR information, STA 1604 may determine whether a first queue size of BSR information of the first stream of frames is smaller than a first pre-determined queue size of BSR information in octets. In another embodiment, STA 1604 may determine whether a first queue size of BSR information of the first stream of frames is larger than a second pre-determined queue size of BSR information in octets.

[0255] In an embodiment, before transmitting the first stream of frames to STA 1602, STA 1604 may perform EDCA and transmit to STA 1602, while STA 1602 operates in the first power state/mode, a frame 1608. In an embodiment, frame 1608 may request that STA 1602 transition from the first power state/mode to the second power state/mode to receive from STA 1604 a PPDU of the second category.

[0256] In an embodiment, frame 1608 may indicate that traffic of the first traffic type is to be transmitted after frame 1608 after STA 1602 transitions to the second power state/mode. In an embodiment, frame 1608 may further indicate a first transmission characteristic of the first traffic type. In an example, the first transmission characteristic may comprise the first transmission duration of the first stream of frames. In another example, the first transmission characteristic may comprise the first number of octets/bytes/bits of the first stream of frames.

[0257] In an embodiment, frame 1608 may comprise a control frame. In an example, the control frame may comprise an ICF. In an example, the ICF may comprise an MU-RTS trigger frame ora BAR frame.

[0258] In an embodiment, STA 1602 may transition, in response to frame 1608, from the first power state/mode to the second power state/mode. As shown in FIG. 16, on receiving frame 1608 from STA 1604, STA 1602 may respond with an ICR 1610 and may initiate a transition from the first power state/mode to the second power state/mode at a time T1. In an embodiment, AP operates in the second power state/mode during a second time period. In an example, the second time period may begin at time T 1.

[0259] In an embodiment, STA 1602 may determine, from frame 1608, a TXOP duration, a bandwidth, and/or a modulation and coding scheme (MCS) of a PPDU carrying the first stream of frames of the first traffic type. STA 1602 may turn on/enable receiver capabilities based on the bandwidth and MCS indicated in frame 1608 In an implementation, STA 1602 may use the TXOP duration and the bandwidth indicated in frame 1608 to reserve a suitable channel for the PPDU. In an implementation, STA 1602 may perform a clear channel assessment (CCA) procedure over the channel to be used by STA 1604 for the transmission of the PPDU. After a successful CCA procedure, STA 1602 may transmit an ICR 1610 to STA 1604. ICR 1610 maybe configured to reserve the channel to be used by STA 1604 for the transmission of the PPDU. In an implementation, ICR 1610 may be a CTS frame that indicates the channel to be used by STA 1604 for the transmission of the PPDU.

[0260] On receiving ICR 1610, STA 1604 may initiate transmission of the PPDU carrying the first stream of frames of the first traffic type. The PPDU may comprise a third frame comprising the one or more first data frames (e.g. , comprising MPDUs 1612-1 and 1612-2).

[0261] As shown in FIG. 16, in an example, a first data frame of the one or more first data frames may comprise MPDU 1612-1 and a second data frame of the one or more first data frames may comprise MPDU 1612-2 different from the first MPDU. In another example (not shown in FIG. 16), the one or more first data frames may be comprised in a same MPDU. For example, the first data frame of the one or more first data frames may comprise a first MSDU and the second data frame of the one or more first data frames may comprise a second MSDU different from the first MSDU. In another example (not shown in FIG. 16), the one or more first data frames may be transmitted in separate PPDUs to STA 1602. [0262] In an implementation, STA 1604 transmits the PPDU carrying the first stream of frames of the first traffic type a SIFS after receiving ICR 1610. After receiving the PPDU, STA 1602 may transmit a BA frame 1614 to STA 1604. In an implementation, STA 1602 may return to the first power state/mode at a time T2 after receiving the PPDU. STA 1602 may transmit BA frame 1614 while in the second power state/mode or after returning to the first power state/mode. In an example, the second time period may be end at time T2.

[0263] In an example, after time T2, STA 1604 may transmit to STA 1602 a third data frame of the second traffic type. As shown in FIG. 16, the third data frame may comprise an MPDU 1612-3 carrying traffic of the second traffic type. In an example, STA 1602 may receive the third data frame while operating in the first power state/mode. In another example, STA 1602 may receive the third data frame while operating in the other mode (not shown in FIG. 16).

[0264] In an embodiment (not shown in FIG. 16), STA 1604 may be configured to transmit to STA 1602, while STA 1602 operates in the second power state/mode, traffic of the first traffic type. In an embodiment, STA 1604 may be configured not to transmit to STA 1602, while STA 1602 operates in the second power state/mode, traffic of a second traffic type.

[0265] As shown in FIG. 16, based on transmitting frame 1606, STA 1602 may transition from the first power state/mode to the second power state/mode only to receive traffic of the first traffic type from STA 1604. STA 1604 may only transmit to STA 1602 traffic of the first traffic type while STA 1602 operates in the second power state/mode. In contrast, STA 1602 may receive traffic of the second traffic type when operating in the first power state/mode. This operation may enable STA 1602 to reduce the amount of time that STA 1602 operates in the second power state/mode, which reduces the overall power consumption of STA 1602.

[0266] As shown in FIG. 16, based on transmitting frame 1606, STA 1602 may transition from the first power state/mode to the second power state/mode only to receive from STA 1604 traffic of the first traffic type that satisfies the first condition. STA 1604 may only transmit to STA 1602 traffic of the first traffic type that satisfies the first condition while STA 1602 operates in the second power state/mode. In contrast, STA 1602 may receive traffic of the second traffic type when operating in the first power state/mode. This operation may enable STA 1602 to reduce the amount of time that STA 1602 operates in the first power state/mode and to receive more data during the second power state/mode, which also reduces the overall power consumption of STA 1602.

[0267] FIG. 17 illustrates an example 1700 of a PS mode procedure according to an embodiment. Example 1700 is provided for the purpose of illustration only and is not limiting. As shown in FIG. 17, example 1700 may include a STA 1702 and a STA 1704. STA 1702 may comprise an AP STA. STA 1704 may comprise a non-AP STA associated with STA 1702. STA 1702 and STA 1704 may each comprise a multi-link device (MLD).

[0268] It is assumed in example 1700 that STA 1702 implements the power save (PS) mode illustrated in FIG. 17, which may be denoted as a dynamic PS mode or a low power listening (LPL) mode.

[0269] In an implementation, STA 1702 implementing the PS mode illustrated in FIG. 17 may be in a first power state/mode of the PS mode or in a second power state/mode of the PS mode. The first power state/mode may be referred to as a lower capability state/mode, a lower power receive state/mode or a listen/listening state/mode. The second power state/mode may be referred to as a higher capability state/mode, a higher power receive state/mode or an awake state/mode. While in the first power state/mode, STA 1702 is capable of receiving PPDUs of a first category. While in the second power state/mode, STA 1702 is capable of receiving PPDUs of the first category and PPDUs of a second category. In an implementation, STA 1702 is not capable of receiving PPDUs of the second category during the first power state/mode. In an implementation, STA 1702 is capable of receiving PPDUs of only the first category during the first power state/mode.

[0270] In an implementation, the first category may include PPDUs having a non-HT PPDU format such as non-HT PPDU 810 described above. In another implementation, the first category may include, additionally or alternatively, PPDUs having a data rate that is less than or equal to 24 Mbps, a bandwidth of 20 MHz, and/or a single spatial stream. The second category may include PPDUs having a format other than the non-HT PPDU format. For example, the second category may include PPDUs having a high throughput (HT) format such as HT mixed mode PPDU 820, a VHT format such as VHT PPDU 830, an HE PPDU such as HE SU PPDU 910, HE MU PPDU 920, or HE ER SU PPDU 930, an EHT PPDU such as EHT MU PPDU 1000, an ultra-high reliability (UHR) PPDU, or a physical layer version identifier field. Additionally, or alternatively, the second category may include PPDUs having a data rate that is greater than 24 Mbps, a bandwidth greater than 20 MHz, and/or a plurality of spatial streams.

[0271] STA 1702 may transition between the first power state/mode and the second power state/mode of the PS mode. In an implementation, to reduce the power consumption of the STA, the first power state/mode may correspond to a default state/mode of the PS mode. As such, the STA may operate in the first power state/mode and may transition to the second power state/mode as needed.

[0272] Similar to AP 1402 described in FIG. 14, STA 1702 may support another mode of operation. The other mode may correspond to an active mode or to a power saving mode different than the PS mode illustrated in FIG. 17. The other mode may have one or more power states. STA 1702 may be capable of receiving PPDUs of the first category and/or of the second category in any power state/mode of the other mode. [0273] In an embodiment, PPDUs of the first category and PPDUs of the second category may carry data frames comprising traffic of a first traffic type and traffic of a second traffic type.

[0274] In an embodiment, the first traffic type may comprise low latency traffic or high-reliability traffic. In an embodiment, the first traffic type may comprise a first traffic identifier (TID). In an embodiment, the first traffic type may comprise a first traffic category (TC) or a first traffic stream (TS). In an embodiment, the first traffic type may comprise a first access category (AC). For example, the first AC may be associated with video (AC_VI) or voice (AC_VO). In another embodiment, the first traffic type may comprise a first stream classification service (SCS) stream. In another embodiment, the first traffic type may comprise a first SCS identifier (SCSID).

[0275] In an embodiment, the second traffic type may be different from the first traffic type. In an embodiment, the second traffic type may comprise a second TID. The second TID may be different from the first TID. In an embodiment, the second traffic type may comprise a second TC or a second TS. The second TC may be different from the first TC. The second TS may be different from the first TS. In an embodiment, the second traffic type may comprise a second AC. The second AC may be different from the first AC. In another embodiment, the second traffic type may comprise a second SCS stream. The second SCS stream may be different from the first SCS stream. In another embodiment, the second traffic type may comprise a second SCSID. The second SCSID may be different from the first SCSID.

[0276] In an implementation, while in the first power state/mode, STA 1702 is capable of receiving data frames carried by PPDUs of the first category. In an embodiment, STA 1702 may be capable of receiving traffic of the first traffic type and/or traffic of the second traffic type while operating in the first power state/mode. In an implementation, while STA 1702 operates in the first power state/mode, data frames carried by PPDUs of the first category may comprise traffic of the first traffic type or traffic of the second traffic type.

[0277] In another implementation, while in the first power state/mode, STA 1702 is not capable of receiving the data frames carried by PPDUs of the first category. In an embodiment, STA 1702 may not be capable of receiving traffic of the first traffic type or traffic of the second traffic type while operating in the first power state/mode. In an implementation, while STA 1702 operates in the first power state/mode, data frames carried by PPDUs of the first category may comprise traffic of the first traffic type or traffic of the second traffic type.

[0278] In an implementation, while in the second power state/mode, STA 1702 is capable of receiving data frames carried by PPDUs of the first category or the second category. In an embodiment, STA 1702 may be capable of receiving traffic of the first traffic type while operating in the second power state/mode. In an implementation, while STA 1702 operates in the second power state/mode, data frames carried by PPDUs of the first category or the second category may comprise traffic of the first traffic type. In another embodiment, STA 1702 may be capable of receiving traffic of the second traffic type while operating in the second power state/mode. In an implementation, while STA 1702 operates in the second power state/mode, data frames carried by PPDUs of the first category or the second category may comprise traffic of the second traffic type.

[0279] In an embodiment, before example 1700 begins, STA 1704 may initiate a SCS procedure with STA 1702. In an example, STA 1704 may transmit to STA 1702 a SCS request frame indicating the first SCSID. In an example, the SCS request frame may further indicate the second SCSID. In response, STA 1704 may receive a SCS response frame from STA 1704 indicating a first value associated with the first SCSID. In an example, the SCS response frame may further indicate a second value associated with the second SCSID.

[0280] Similar to AP 1502 described in FIG. 15, as illustrated in example 1700, STA 1702 is operating in the PS mode. It is assumed that STA 1702 is willing to reserve the second power state/mode for receiving data frames comprising traffic of the first traffic type during due to a reason. For example, traffic of the first traffic type is necessary to be received by STA 1702 using high receive capability in the second power state/mode. In an implementation, traffic of the first traffic type may require low-latency or high-reliability transmissions. In an implementation, traffic of the first traffic type may require high throughput transmissions. In an implementation, traffic of the first traffic type may include voice or video streams.

[0281] It is assumed in example 1700 that STA 1702 supports the PS mode with traffic type awareness capability. STA 1702 supporting the PS mode with traffic type awareness capability may include STA 1702 having the capability to transmit to another STA a first frame (such as frame 1706 described below) indicating a first traffic type that the other STA is allowed to transmit to STA 1702 while STA 1702 operates in the second power state/mode. STA 1702 supporting the PS mode with traffic type awareness capability may further include STA 1702 having the capability to receive from the other STA and while STA 1702 operates in the first power state/mode of the PS mode, a second frame (such as frame 1708 described below). STA 1702 supporting the PS mode with traffic type awareness capability may further include STA 1702 having the capability to transition between the first power state/mode and the second power state/mode. STA 1702 supporting the PS mode with traffic type awareness capability may further include STA 1702 having the capability to receive from the other STA and while STA 1702 operates in the second power state/mode, a third frame comprising one or more first data frames of the first traffic type (such as MPDUs 1712-1 , 1712-2 described below). [0282] It is also assumed in example 1700 that STA 1704 supports the PS mode with traffic type awareness capability. STA 1704 supporting the PS mode with traffic type awareness capability may include STA 1704 having the capability to receive from another STA the first frame (such as frame 1706 described below) indicating a first traffic type that STA 1704 is allowed to transmit to the other STA while the other STA operates in the second power state/mode of the PS mode. STA 1704 supporting the PS mode with traffic type awareness capability may further include STA 1704 having the capability to receive from the other STA and while the other STA operates in the second power state/mode, the third frame comprising one or more first data frames of the first traffic type (such as MPDUs 1712-1 , 1712-2 described below). [0283] As shown in FIG. 17, the procedure illustrated in example 1700 may begin with STA 1702 transmitting a frame 1706 using EDCA during a first time period. In an embodiment, frame 1706 may indicate a first traffic type that STA 1704 is allowed to transmit to STA 1702 while STA 1702 operates in the second power state/mode. In an embodiment, the first traffic type that STA 1704 is allowed to transmit may comprise the first traffic type described above.

[0284] In an embodiment, STA 1704 may be allowed to transmit a first stream of frames of the first traffic type to STA 1702 while STA 1702 operates in the second power state/mode, on condition that the first stream of frames satisfies a first condition. [0285] In an embodiment, the first condition may comprise a first transmission duration of the first stream of frames being shorter than a first pre-determined duration. For example, the first pre-determined duration may be 100 pis or 1 ,000 pis. In another embodiment, the first condition may comprise a first transmission duration of the first stream of frames being longer than a second pre-determined duration. For example, the second pre-determined duration may be 100 pis or 1,000 pis.

[0286] In an embodiment, the first condition may comprise a first number of octets/bytes/bits of the first stream of frames being lower than a first pre-determined number of octets/bytes/bits. For example, the first pre-determined number may be 100 bytes or 1,000 bytes. In another embodiment, the first condition may comprise a first number of octets/bytes/bits of the first stream of frames being higher than a second pre-determined number of octets/bytes/bits. For example, the second pre-determined number may be 100 bytes or 1 ,000 bytes.

[0287] In an embodiment, the first condition may comprise a first queue size of BSR information of the first steam of frames being smaller than a first pre-determined queue size of BSR information. The first pre-determined queue size of BSR information may indicate an amount of buffered traffic, in units of octets. In an embodiment, the first condition may comprise a first queue size of BSR information of the first steam of frames being larger than a second pre-determined queue size of BSR information. The second pre-determined queue size of BSR information may indicate an amount of buffered traffic, in units of octets.

[0288] In an embodiment, the first condition may be indicated in frame 1706. In an embodiment, the first condition may comprise a dynamic condition (e.g., that may vary over time). The first condition may thus be repeatedly signaled by STA 1702. In another embodiment, the first condition may be a static condition (e.g., that does not vary over the time). The first condition may thus be signaled only once by STA 1702 or may be pre-configured in STA 1702 and STA 1704.

[0289] In an embodiment, frame 1706 may further indicate a second traffic type that STA 1704 is allowed to transmit to STA 1702 while STA 1702 operates in the second power state/mode. In an embodiment, the second traffic type that STA 1704 is allowed to transmit may comprise the second traffic type described above.

[0290] In an embodiment, the first traffic type may be associated with a first priority. The first priority may correspond to a priority for transmission of traffic of the first traffic type, by STA 1704 to STA 1702, while STA 1702 operates in the second power state/mode. In an embodiment, the first priority may comprise a priority of the first TC. For example, the priority of the first traffic category may comprise a first user priority (UP). In another embodiment, the first priority may comprise a priority of the first AC.

[0291] In an embodiment, the second traffic type may be associated with a second priority. The second priority may correspond to a priority for transmission of traffic of the second traffic type, by STA 1704 to STA 1702, while STA 1702 operates in the second power state/mode. In an embodiment, the second priority may comprise a priority of the second TC. For example, the priority of the second traffic category may comprise a second UP. In another embodiment, the first priority may comprise a priority of the second AC.

[0292] In an embodiment, the first priority may be higher than the second priority. As such, STA 1704 may prioritize transmission of traffic of the first traffic type over transmission of traffic of the second traffic type to STA 1702 while STA 1702 operates in the second power state/mode. In another embodiment, the first priority may be lower than the second priority. As such, STA 1704 may prioritize transmission of traffic of the second traffic type over transmission of traffic of the first traffic type to STA 1702 while STA 1702 operates in the second power state/mode. In an embodiment, frame 1706 may indicate the first priority and the second priority.

[0293] In an embodiment, STA 1704 may be allowed to transmit a second stream of frames of the second traffic type to STA 1702 while STA 1702 operates in the second power state/mode, on condition that the second stream of frames satisfies a second condition.

[0294] In an embodiment, the second condition may comprise a second transmission duration of the second stream of frames being shorter than a third pre-determined duration. For example, the third pre-determined duration may be 100 s or 1 ,000 ps. In another embodiment, the second condition may comprise a second transmission duration of the second stream of frames being longer than a fourth pre-determined duration. For example, the fourth pre-determined duration may be 100 ps or 1,000 ps.

[0295] In an embodiment, the second condition may comprise a second number of octets/bytes/bits of the second stream of frames being lower than a third pre-determined number of octets/bytes/bits. For example, the third predetermined number may be 100 bytes or 1,000 bytes. In another embodiment, the second condition may comprise a second number of octets/bytes/bits of the second stream of frames being higher than a fourth pre-determined number of octets/bytes/bits. For example, the fourth pre-determined number may be 100 bytes or 1,000 bytes.

[0296] In an embodiment, the second condition may comprise a second queue size of BSR information of the second steam of frames being smaller than a third pre-determined queue size of BSR information. The third pre-determined queue size of BSR information may indicate an amount of buffered traffic, in units of octets. In an embodiment, the second condition may comprise a second queue size of BSR information of the first steam of frames being larger than a fourth pre-determined queue size of BSR information. The fourth pre-determined queue size of BSR information may indicate an amount of buffered traffic, in units of octets.

[0297] In an embodiment, the second condition may be indicated in frame 1706. In an embodiment, the second condition may comprise a dynamic condition (e.g . , that may vary over time). The second condition may thus be repeatedly signaled by STA 1702. In another embodiment, the second condition may be a static condition (e.g., that does not vary overthe time). The second condition may thus be signaled only once by STA 1702 or may be pre-configured in STA 1702 and STA 1704.

[0298] In an embodiment, frame 1706 may comprise capability information of STA 1702 indicating support by STA 1702 of the PS mode with traffic type awareness illustrated in FIG. 17. In an embodiment, frame 1706 may announce that STA 1702 is operating in the PS mode with traffic type awareness. In an embodiment, STA 1702 may be operating in a default state/mode of the PS mode during the first time period. In an embodiment, the default state/mode may be the first power state/mode as described above. In another embodiment (not shown in FIG. 17), STA 1702 may operate in the other mode or in the second power state/mode of the PS mode and may transmit frame 1706 announcing that STA 1702 will operate in the PS mode in a future time period. [0299] In an embodiment, frame 1706 may comprise a management frame indicating a broadcast address. In an example, frame 1706 may comprise a beacon frame. In another example, frame 1706 may comprise an action frame.

[0300] STA 1704 may receive frame 1706 and may determine that STA 1702 is operating in the PS mode. As shown in FIG. 17, during the first time period, data may arrive at STA 1704 for transmission to STA 1702. In an example, the data may comprise traffic of the first traffic type and traffic of the second traffic type.

[0301] Based on receiving frame 1706, STA 1704 may match traffic of the first traffic type buffered at STA 1704 to the first traffic type indicated in frame 1706. In an example, traffic of the first traffic type may be buffered in a queue associated with the first traffic category, the first traffic stream, the first access category, or the first SCS stream. In an embodiment, STA 1704 may prepare to transmit to STA 1702 a first stream of frames of the first traffic type when STA 1702 transitions to the second power state/mode. The first stream of frames may comprise one or more first data frames carrying traffic of the first traffic type.

[0302] In an embodiment, where transmission of the first stream of frames to STA 1702 is subject to the first stream of frames satisfying a first condition, STA 1704 may determine whether the first stream of frames satisfies the first condition. [0303] In an embodiment, wherein the first condition is based on transmission duration, STA 1704 may determine whether a first transmission duration of the first stream of frames is shorter than a first pre-determined duration. In another embodiment, STA 1704 may determine whether a first transmission duration of the first stream of frames is longer than a second pre-determined duration. In an embodiment, the first transmission duration of the first stream of frames may correspond to a combined transmission duration of the one or more first data frames.

[0304] In another embodiment, wherein the first condition is based on transmission size, STA 1704 may determine whether a first number of octets/bytes/bits of the first stream of frames is lower than a first pre-determined number of octets/bytes/bits In another embodiment, STA 1704 may determine whether a first number of octets/bytes/bits of the first stream of frames is higher than a second pre-determined number of octets/bytes/bits. In an embodiment, the first number of octets/bytes/bits of the first stream of frames may correspond to a total number of octets/bytes/bits of the one or more first data frames.

[0305] In another embodiment, wherein the first condition is based on queue size of BSR information, STA 1704 may determine whether a first queue size of BSR information of the first stream of frames is smaller than a first pre-determined queue size of BSR information in octets. In another embodiment, STA 1704 may determine whether a first queue size of BSR information of the first stream of frames is larger than a second pre-determined queue size of BSR information in octets.

[0306] In an embodiment, STA 1704 may further match traffic of the second traffic type buffered at STA 1704 to the second traffic type indicated in frame 1706. In an example, traffic of the second traffic type may be buffered in a queue associated with the second traffic category, the second traffic stream, the second access category, or the second SCS stream. In an embodiment, STA 1704 may prepare to transmit to STA 1702 a first stream of frames of the first traffic type when STA 1702 transitions to the second power state/mode. The first stream of frames may comprise one or more second data frames (such as an MPDU 1712-3) carrying traffic of the second traffic type. [0307] In an embodiment, where transmission of the first stream of frames to STA 1702 is subject to the second stream of frames satisfying a second condition, STA 1704 may determine whether the second stream of frames satisfies the second condition.

[0308] In an embodiment, wherein the second condition is based on transmission duration, STA 1704 may determine whether a second transmission duration of the second stream of frames is shorter than a third pre-determined duration. In another embodiment, STA 1704 may determine whether a second transmission duration of the second stream of frames is longer than a fourth pre-determined duration.

[0309] In another embodiment, wherein the second condition is based on transmission size, STA 1704 may determine whether a second number of octets/bytes/bits of the second stream of frames is lower than a third pre-determined number of octets/bytes/bits. In another embodiment, STA 1704 may determine whether a second number of octets/bytes/bits of the second stream of frames is higher than a fourth pre-determined number of octets/bytes/bits.

[0310] In another embodiment, wherein the second condition is based on queue size of BSR information, STA 1704 may determine whether a second queue size of BSR information of the first stream of frames is smaller than a third predetermined queue size of BSR information in octets. In another embodiment, STA 1704 may determine whether a second queue size of BSR information of the first stream of frames is larger than a fourth pre-determined queue size of BSR information in octets.

[0311] In an embodiment, before transmitting the first stream of frames to STA 1702, STA 1704 may perform EDCA and transmit to STA 1702, while STA 1702 operates in the first power state/mode, a frame 1708. In an embodiment, frame 1708 may request that STA 1702 transition from the first power state/mode to the second power state/mode to receive from STA 1704 a PPDU of the second category.

[0312] In an embodiment, frame 1708 may indicate that traffic of the first traffic type is to be transmitted after frame 1708 when STA 1702 operates in the second power state/mode. In an embodiment, frame 1708 may further indicate a first transmission characteristic of the first traffic type. In an example, the first transmission characteristic may comprise the first transmission duration of the first stream of frames. In another example, the first transmission characteristic may comprise the first number of octets/bytes/bits of the first steam of frames.

[0313] In an embodiment, frame 1708 may further indicate that traffic of the second traffic type is to be transmitted after frame 1708 after STA 1702 transitions to the second power state/mode. In an embodiment, frame 1708 may further indicate a second transmission characteristic of the second traffic type. In an example, the second transmission characteristic may comprise the second transmission duration of the second stream of frames. In another example, the second transmission characteristic may comprise the second number of octets/bytes/bits of the second steam of frames. [0314] In an embodiment, frame 1708 may comprise a control frame. In an example, the control frame may comprise an ICF. In an example, the ICF may comprise an MU-RTS trigger frame ora BAR frame.

[0315] In an embodiment, STA 1702 may transition, in response to frame 1708, from the first power state/mode to the second power state/mode. As shown in FIG. 17, on receiving frame 1708 from STA 1704, STA 1702 may respond with an ICR 1710 and may initiate a transition from the first power state/mode to the second power state/mode at a time T1. In an embodiment, AP operates in the second power state/mode during a second time period. In an example, the second time period may begin at time T1.

[0316] In an embodiment, STA 1702 may determine, from frame 1708, a TXOP duration, a bandwidth, and/or a modulation and coding scheme (MCS) of a PPDU carrying the first stream of frames of the first traffic type. In an embodiment, the PPDU may further carry the second steam of frames of the second traffic type. STA 1702 may turn on/enable receiver capabilities based on the bandwidth and MCS indicated in frame 1708. In an implementation, STA 1702 may use the TXOP duration and the bandwidth indicated in frame 1708 to reserve a suitable channel for the PPDU. In an implementation, STA 1702 may perform a clear channel assessment (CCA) procedure over the channel to be used by STA 1704 for the transmission of the PPDU. After a successful CCA procedure, STA 1702 may transmit an ICR 1710 to STA 1704. ICR 1710 may be configured to reserve the channel to be used by STA 1704 for the transmission of the PPDU. In an implementation, ICR 1710 may be a CTS frame that indicates the channel to be used by STA 1704 for the transmission of the PPDU

[0317] On receiving ICR 1710, STA 1704 may initiate transmission of the PPDU carrying the first stream of frames of the first traffic type. The PPDU may comprise a third frame comprising the one or more first data frames of the first stream of the frames. In an embodiment, the PPDU may further comprise the second stream of frames of the second traffic type. The third frame may further comprise the one or more second data frames of the first stream of frames.

[0318] As shown in FIG. 17, in an example, a first data frame of the one or more first data frames may comprise an MPDU 1712-1 and a second data frame of the one or more first data frames may comprise an MPDU 1712-2 different from MPDU 1712-1. In an example, a first data frame of the one or more second data frames may comprise an MPDU 1712-3 different from MPDU 1712-1 or MPDU 1712-2. In another example (not shown in FIG. 17), the first and second data frames of the one or more first data frames and the first data frame of the one or more second data frames may be comprised in a same MPDU. For example, the first and second data frames of the one or more first data frames may comprise a first MSDU and a second MSDU different from the first MSDU. For example, the first data frame of the one or more second data frames may comprise a third MSDU different from the first MSDU or the second MDSU. In another example (not shown in FIG. 17), the first data frame of the one or more second data frames may be transmitted in a separate PPDU different than the PPDU carrying the one or more first data frames. In another example (not shown in FIG. 17), the second data frame of the one or more first data frames and the first data frame of the one or more second data frames may be transmitted in a same PPDU. In another example (not shown in FIG. 17), the first and second data frames of the one or more first data frames and the first data frame of the one or more second data frames may be transmitted in separate PPDUs.

[0319] In an implementation, STA 1704 transmits the PPDU carrying the first stream of frames of the first traffic type and the second stream of frames of the second traffic type a SIFS after receiving ICR 1710. After receiving the PPDU, STA 1702 may transmit a BA frame 1714 to STA 1704. In an implementation, STA 1702 may return to the first power state/mode at a time T2 after receiving the PPDU. STA 1702 may transmit BA frame 1714 while in the second power state/mode or after returning to the first power state/mode. In an example, the second time period may be end at time T2.

[0320] As shown in FIG. 17, based on transmitting frame 1706, STA 1702 transitions from the first power state/mode to the second power state/mode to receive traffic of the first traffic type. By setting the first priority associated with the first traffic type higher than the second priority associated with the second traffic type, STA 1702 prioritizes reception of traffic of the first traffic while operating in the second power state/mode. Additionally, by setting the second condition, STA 1702 may limit the amount of traffic of the second traffic type that STA 1702 receives while operating in the second power state/mode. This operation may enable STA 1702 to reduce the amount of time that STA 1702 operates in the second power state/mode, which reduces the overall power consumption of STA 1702. This operation may enable STA 1702 to reduce the amount of time that STA 1702 operates in the first power state/mode and to receive more data during the second power state/mode, which also reduces the overall power consumption of STA 1702.

[0321] FIG. 18 illustrates an example 1800 of a PS mode procedure according to an embodiment. Example 1800 is provided for the purpose of illustration only and is not limiting. As shown in FIG. 18, example 1800 may include a STA 1802 and a STA 1804. STA 1802 may comprise an AP STA. STA 1804 may comprise a non-AP STA associated with STA 1802. STA 1802 and STA 1804 may each comprise a multi-link device (MLD).

[0322] It is assumed in example 1800 that STA 1802 implements the power save (PS) mode illustrated in FIG. 18, which may be denoted as a dynamic PS mode or a low power listening (LPL) mode.

[0323] In an implementation, STA 1802 implementing the PS mode illustrated in FIG. 18 may be in a first power state/mode of the PS mode or in a second power state/mode of the PS mode. The first power state/mode may be referred to as lower capability state/mode, a lower power receive state/mode or a listen/listening state/mode. The second power state/mode may be referred to as a higher capability state/mode, a higher power receive state/mode or an awake state. While in the first power state/mode, STA 1802 is capable of receiving PPDUs of a first category. While in the second power state/mode, STA 1802 is capable of receiving PPDUs of the first category and PPDUs of a second category. In an implementation, STA 1802 is not capable of receiving PPDUs of the second category during the first power state/mode. In an implementation, STA 1802 is capable of receiving PPDUs of only the first category during the first power state/mode. [0324] In an implementation, the first category may include PPDUs having a non-HT PPDU format such as non-HT PPDU 810 described above. In another implementation, the first category may include, additionally or alternatively, PPDUs having a data rate that is less than or equal to 24 Mbps, a bandwidth of 20 MHz, and/or a single spatial stream. The second category may include PPDUs having a format other than the non-HT PPDU format. For example, the second category may include PPDUs having a high throughput (HT) format such as HT mixed mode PPDU 820, a VHT format such as VHT PPDU 830, an HE PPDU such as HE SU PPDU 910, HE MU PPDU 920, or HE ER SU PPDU 930, an EHT PPDU such as EHT MU PPDU 1000, an ultra-high reliability (UHR) PPDU, or a physical layer version identifier field. Additionally, or alternatively, the second category may include PPDUs having a data rate that is greater than 24 Mbps, a bandwidth greater than 20 MHz, and/or a plurality of spatial streams. [0325] STA 1802 may transition between the first power state/mode and the second power state/mode of the PS mode. In an implementation, to reduce the power consumption of the STA, the first power state/mode may correspond to a default state/mode of the PS mode. As such, the STA may operate in the first power state/mode and may transition to the second power state/mode as needed.

[0326] Similar to AP 1402 described in FIG. 14, STA 1802 may support another mode of operation. The other mode may correspond to an active mode or to a power saving mode different than the PS mode illustrated in FIG. 18. The other mode may have one or more power states. STA 1802 may be capable of receiving PPDUs of the first category and/or of the second category in any power state/mode of the other mode.

[0327] In an embodiment, PPDUs of the first category and PPDUs of the second category may carry data frames comprising traffic of a first traffic type and traffic of a second traffic type.

[0328] In an embodiment, the first traffic type may comprise low latency traffic or high-reliability traffic. In an embodiment, the first traffic type may comprise a first traffic identifier (TID). In an embodiment, the first traffic type may comprise a first traffic category (TC) or a first traffic stream (TS). In an embodiment, the first traffic type may comprise a first access category (AC). For example, the first AC may be associated with video (AC_VI) or voice (AC_VO). In another embodiment, the first traffic type may comprise a first stream classification service (SCS) stream. In another embodiment, the first traffic type may comprise a first SCS identifier (SCSID).

[0329] In an embodiment, the second traffic type may be different from the first traffic type. In an embodiment, the second traffic type may comprise a second TID. The second TID may be different from the first TID. In an embodiment, the second traffic type may comprise a second TC or a second TS. The second TC may be different from the first TC. The second TS may be different from the first TS. In an embodiment, the second traffic type may comprise a second AC. The second AC may be different from the first AC. In another embodiment, the second traffic type may comprise a second SCS stream. The second SCS stream may be different from the first SCS stream. In another embodiment, the second traffic type may comprise a second SCSID. The second SCSID may be different from the first SCSID.

[0330] In an implementation, while in the first power state/mode, STA 1802 is capable of receiving data frames carried by PPDUs of the first category. In an embodiment, STA 1802 may be capable of receiving traffic of the first traffic type and/or traffic of the second traffic type while operating in the first power state/mode. In an implementation, while STA 1802 operates in the first power state/mode, data frames carried by PPDUs of the first category may comprise traffic of the first traffic type or traffic of the second traffic type.

[0331] In another implementation, while in the first power state/mode, STA 1802 is not capable of receiving the data frames carried by PPDUs of the first category. In an embodiment, STA 1802 may not be capable of receiving traffic of the first traffic type or traffic of the second traffic type while operating in the first power state/mode. In an implementation, while STA 1802 operates in the first power state/mode, data frames carried by PPDUs of the first category may comprise traffic of the first traffic type or traffic of the second traffic type.

[0332] In an implementation, while in the second power state/mode, STA 1802 is capable of receiving data frames carried by PPDUs of the first category or the second category. In an embodiment, STA 1802 may be capable of receiving traffic of the first traffic type while operating in the second power state/mode. In an implementation, while STA 1802 operates in the second power state/mode, data frames carried by PPDUs of the first category or the second category may comprise traffic of the first traffic type. In another embodiment, STA 1802 may be capable of receiving traffic of the second traffic type while operating in the second power state/mode. In an implementation, while STA 1802 operates in the second power state/mode, data frames carried by PPDUs of the first category or the second category may comprise traffic of the second traffic type.

[0333] In an embodiment, before example 1800 begins, STA 1804 may initiate an SCS procedure with STA 1802. In an example, STA 1804 may transmit to STA 1802 an SCS request frame indicating the first SCSID (associated with traffic of the first traffic type). In an example, the SCS request frame may further indicate the second SCSID (associated with traffic of the second traffic type). In response, STA 1804 may receive an SCS response frame from STA 1804 indicating a first value associated with the first SCSI D. In an example, the SCS response frame may further indicate a second value associated with the second SCSID.

[0334] In an embodiment, STA 1802 may be configured to reserve the second power state/mode for receiving data frames comprising traffic of the first traffic type. This capability, in conjunction with the PS mode described above, may provide a PS mode with traffic type awareness capability. For example, the second power state/mode may correspond to a higher capability state/mode, a higher power receive state/mode with higher receive capabilities than the first power state/mode. For various reasons, it may be required that traffic of the first traffic type be received by AP 1802 while in the second power state/mode. For example, in an implementation, traffic of the first traffic type may require low-latency, high- reliability, and/or high throughput. In an implementation, traffic of the first traffic type may include voice or video streams. [0335] It is assumed in example 1800 that STA 1802 supports the PS mode with traffic type awareness capability. STA 1802 supporting the PS mode with traffic type awareness capability may include STA 1802 having the capability to transmit to another STA a first frame (such as frame 1806 described below) indicating a preferred/recommended traffic type that STA 1802 prefers to receive while STA 1802 operates in the second power state/mode. STA 1802 supporting the PS mode with traffic type awareness capability may further include STA 1802 having the capability to receive from the other STA and while STA 1802 operates in the first power state/mode of the PS mode, a second frame (such as frame 1808 described below). STA 1802 supporting the PS mode with traffic type awareness capability may further include STA 1802 having the capability to transition between the first power state/mode and the second power state/mode. STA 1802 supporting the PS mode with traffic type awareness capability may further include STA 1802 having the capability to receive from the other STA and while STA 1802 operates in the second power state/mode, a third frame comprising one or more first data frames of the preferred/recommended traffic type (such as MPDU 1812 described below).

[0336] It is also assumed in example 1800 that STA 1804 supports the PS mode with traffic type awareness capability. STA 1804 supporting the PS mode with traffic type awareness capability may include STA 1804 having the capability to receive from another STA the first frame (such as frame 1806 described below) indicating a preferred/recommended traffic type that another STA prefers to receive while the other STA operates in the second power state/mode of the PS mode. STA 1804 supporting the PS mode with traffic type awareness capability may further include STA 1804 having the capability to receive from the other STA and while the other STA operates in the second power state/mode, the third frame comprising one or more first data frames of the preferred/recommended traffic type (such as MPDU 1812 described below).

[0337] As shown in FIG. 18, the procedure illustrated in example 1800 may begin with STA 1802 transmitting a frame 1806 using EDCA during a first time period. In an embodiment, frame 1806 may indicate a preferred/recommended traffic type that STA 1802 prefers to receive while STA 1802 operates in the second power state/mode. STA 1804 is recommended to transmit to STA 1802 traffic of the preferred/recommended traffic type while STA 1802 operates in the second power state/mode. In an embodiment, the preferred/recommended traffic type may comprise the first traffic type as described above.

[0338] In an embodiment, frame 1806 may further indicate a non-preferred/non-recommended traffic type that STA 1802 prefers not to receive while STA 1802 operates in the second power state/mode. STA 1804 is recommended not to transmit to STA 1802 traffic of the non-preferred/non-recommended traffic type while STA 1802 operates in the second power state/mode. In an embodiment, the non-preferred/non-recommended traffic type may comprise the second traffic type described above.

[0339] In an embodiment, frame 1806 may comprise capability information of STA 1802 indicating support by STA 1802 of the PS mode with traffic type awareness illustrated in FIG. 18. In an embodiment, frame 1806 may announce that STA 1802 is operating in the PS mode with traffic type awareness. In an embodiment, STA 1802 may be operating in a default state/mode of the PS mode during the first time period. In an embodiment, the default state/mode may be the first power state/mode as described above. In another embodiment (not shown in FIG. 18), STA 1802 may operate in the other mode or in the second power state/mode of the PS mode and may transmit frame 1806 announcing that STA 1802 will operate in the PS mode in a future time period.

[0340] In an embodiment, frame 1806 may comprise a management frame indicating a broadcast address. In an example, frame 1806 may comprise a beacon frame. In another example, frame 1806 may comprise an action frame.

[0341] STA 1804 may receive frame 1806 and may determine that STA 1802 is operating in the PS mode. As shown in FIG. 18, during the first time period, data may arrive at STA 1804 for transmission to STA 1802. In an example, the data may comprise traffic of the preferred traffic type and traffic of the non-preferred traffic type.

[0342] Based on receiving frame 1806, STA 1804 may match traffic of the first traffic type buffered at STA 1804 to the preferred traffic type indicated in frame 1806. In an example, traffic of the preferred traffic type may be buffered in a queue associated with the first traffic category, the first traffic stream, the first access category, or the first SCS stream. In an embodiment, STA 1804 may prepare to transmit to STA 1802 a first stream of frames of the preferred traffic type when STA 1802 transitions to the second power state/mode. The first stream of frames may comprise one or more first data frames of the preferred traffic type carrying the traffic of the preferred traffic type when STA 1802 transitions to the second power state/mode. [0343] In another embodiment, STA 1804 may not match traffic of the first traffic type to the preferred traffic type indicated in frame 1806. In an example, even though the second traffic type is not preferred, STA 1804 may decide to still transmit traffic of the second traffic type while STA 1802 operates in the second power state/mode. In an embodiment, STA 1804 may prepare to transmit to STA 1802 a second stream of frames of the non-preferred traffic type when STA 1802 transitions to the second power state/mode. The second stream of frames may comprise one or more second data frame of the non-preferred traffic type carrying the traffic of the non-preferred traffic type when STA 1802 transitions to the second power state/mode. In an example, traffic of the non-preferred traffic type may be buffered in the second traffic category, the second traffic stream, the second access category, or the second SCS stream.

[0344] In an embodiment, before transmitting the first stream or the second stream of frames to STA 1802, STA 1804 may perform EDCA, transmit to STA 1802 and while STA 1802 operates in the first power state/mode, a frame 1808. In an embodiment, frame 1808 may request that STA 1802 transition from the first power state/mode to the second power state/mode to receive from STA 1804 a PPDU of the second category.

[0345] In an embodiment, frame 1808 may indicate that the preferred traffic type that is to be transmitted after frame 1808 after STA 1802 transitions to the second power state/mode. In an embodiment, frame 1808 may further indicate a first transmission characteristic of the preferred traffic type. In an example, the first transmission characteristic may comprise the first transmission duration of the first stream of frames. In another example, the first transmission characteristic may comprise the first number of octets/bytes/bits of the first steam of frames.

[0346] In another embodiment, frame 1708 may indicate the non-preferred traffic type that is to be transmitted after frame 1708 after STA 1702 transitions to the second power state/mode. In an embodiment, frame 1708 may further indicate a second transmission characteristic of the non-preferred traffic type. In an example, the second transmission characteristic may comprise the second transmission duration of the second stream of frames. In another example, the second transmission characteristic may comprise the second number of octets/bytes/bits of the second steam of frames. [0347] In an embodiment, frame 1808 may comprise a control frame. In an example, the control frame may comprise an ICF. In an example, the ICF may comprise an MU-RTS trigger frame ora BAR frame.

[0348] In an embodiment, STA 1802 may transition, in response to frame 1808, from the first power state/mode to the second power state/mode. As shown in FIG. 18, on receiving frame 1808 from STA 1804, STA 1802 may respond with an ICR 1810 and may initiate a transition from the first power state/mode to the second power state/mode at a time T1. In an embodiment, AP operates in the second power state/mode during a second time period. In an example, the second time period may begin at time T1.

[0349] In another embodiment, ICR 1810 may indicate whether STA 1802 accepts or rejects the transition request indicated in frame 1808. In an embodiment, STA 1802 may accept the transition request based on frame 1808 indicating that traffic of the first traffic type (i.e. , the preferred/recommended traffic type) is to be transmitted. In another embodiment, STA 1802 may accept the transition request based on the first transmission characteristic (e.g., transmission duration, transmission size) of the first traffic type. In another embodiment, STA 1802 may reject the request based on frame 1808 indicating that traffic of the second traffic type (i.e., the non-preferred/non-recommended traffic type) is to be transmitted. In another embodiment, STA 1802 may reject the request based on the second transmission characteristic (e.g., transmission duration, transmission size) of the second traffic type. In a further embodiment, despite frame 1808 indicating that traffic of the second traffic type is to be transmitted, STA 1802 may accept the transition request based on the second transmission characteristic (e.g., transmission duration, transmission size) of the second traffic type. STA 1802 may transition or not to the second power state/mode based on whether ICR 1810 accepts or rejects the transition request.

[0350] In an embodiment, STA 1802 may determine, from frame 1808, a TXOP duration, a bandwidth, and/or a modulation and coding scheme (MCS) of a PPDU. In an embodiment, the PPDU may carry the first steam of frames of the preferred traffic type. In another embodiment, the PPDU may carry the second stream of frames of the non-preferred traffic type. STA 1802 may turn on/enable receiver capabilities based on the bandwidth and MCS indicated in frame 1808. In an implementation, STA 1802 may use the TXOP duration and the bandwidth indicated in frame 1808 to reserve a suitable channel for the PPDU. In an implementation, STA 1802 may perform a clear channel assessment (CCA) procedure over the channel to be used by STA 1804 for the transmission of the PPDU. After a successful CCA procedure, STA 1802 may transmit ICR 1810 to STA 1804. ICR 1810 may be configured to reserve the channel to be used by STA 1804 for the transmission of the PPDU. In an implementation, ICR 1810 may be a CTS frame that indicates the channel to be used by STA 1804 for the transmission of the PPDU.

[0351] On receiving ICR 1810, STA 1804 may initiate transmission of the PPDU carrying the first stream of frames of the preferred traffic type or the second stream of frames of the non-preferred traffic type. The PPDU may comprise a third frame comprising the one or more first data frames and/or the one or more second data frames.

[0352] As shown in FIG. 18, in an example, the third frame may comprise an MPDU 1812. In another example (not shown in FIG. 18), the third frame may comprise one or more MSDUs.

[0353] In an implementation, STA 1804 transmits the PPDU carrying the first stream of frames of the preferred traffic type or the second stream of frames of the non-preferred traffic type a SIFS after receiving ICR 1810. After receiving the PPDU, STA 1802 may transmit a BA frame 1814 to STA 1804. In an implementation, STA 1802 may return to the first power state/mode at a time T2 after receiving the PPDU. STA 1802 may transmit BA frame 1814 while in the second power state/mode or after returning to the first power state/mode. In an example, the second time period may be end at time T2.

[0354] As shown in FIG. 18, based on receiving frame 1806, STA 1804 may transmit the third frame comprising MPDU 1812 comprising the first stream of frames of the preferred traffic type. STA 1802 may transition from the first power state/mode to the second power state/mode only to receive traffic of the preferred traffic type when STA 1802 operates in the second power state/mode. This operation may enable STA 1802 to reduce the amount of time that STA 1802 operates in the second power state/mode, which reduces the overall power consumption of STA 1802. This operation may enable STA 1802 to reduce the amount of time that STA 1802 operates in the first power state/mode and to receive more data during the second power state/mode, which also reduces the overall power consumption of STA 1802. [0355] FIG. 19 illustrates an example 1900 of a PS mode procedure according to an embodiment. Example 1900 is provided for the purpose of illustration only and is not limiting. As shown in FIG. 19, example 1900 may include a STA 1902 and a STA 1904. STA 1902 may comprise an AP STA. STA 1904 may comprise a non-AP STA associated with STA 1902. STA 1902 and STA 1904 may each comprise a multi-link device (MLD).

[0356] It is assumed in example 1900 that STA 1902 implements the power save (PS) mode illustrated in FIG. 19, which may be denoted as a dynamic PS mode or a low power listening (LPL) mode.

[0357] In an implementation, STA 1902 implementing the PS mode illustrated in FIG. 19 may be in a first power state/mode of the PS mode or in a second power state/mode of the PS mode. The first power state/mode may be referred to as a lower capability state/mode, a lower power receive state/mode, or a listen/listening state/mode. The second power state/mode may be referred to as a higher capability state/mode, a higher power receive state/mode or an awake state/mode. While in the first power state/mode, STA 1902 is capable of receiving PPDUs of a first category. While in the second power state/mode, STA 1902 is capable of receiving PPDUs of the first category and PPDUs of a second category. In an implementation, STA 1902 is not capable of receiving PPDUs of the second category during the first power state/mode. In an implementation, STA 1902 is capable of receiving PPDUs of only the first category during the first power state/mode.

[0358] In an implementation, the first category may include PPDUs having a non-HT PPDU format such as non-HT PPDU 810 described above. In another implementation, the first category may include, additionally or alternatively, PPDUs having a data rate that is less than or equal to 24 Mbps, a bandwidth of 20 MHz, and/or a single spatial stream. The second category may include PPDUs having a format other than the non-HT PPDU format. For example, the second category may include PPDUs having a high throughput (HT) format such as HT mixed mode PPDU 820, a VHT format such as VHT PPDU 830, an HE PPDU such as HE SU PPDU 910, HE MU PPDU 920, or HE ER SU PPDU 930, an EHT PPDU such as EHT MU PPDU 1000, an ultra-high reliability (UHR) PPDU, or a physical layer version identifier field. Additionally, or alternatively, the second category may include PPDUs having a data rate that is greater than 24 Mbps, a bandwidth greater than 20 MHz, and/or a plurality of spatial streams.

[0359] STA 1902 may transition between the first power state/mode and the second power state/mode of the PS mode. In an implementation, to reduce the power consumption of the STA, the first power state/mode may correspond to a default state/mode of the PS mode. As such, the STA may operate in the first power state/mode and may transition to the second power state/mode as needed.

[0360] Similar to AP 1402 described in FIG. 14, STA 1902 may support another mode of operation. The other mode may correspond to an active mode or to a power saving mode different than the PS mode illustrated in FIG. 19. The other mode may have one or more power states. STA 1902 may be capable of receiving PPDUs of the first category and/or of the second category in any power state/mode of the other mode.

[0361] In an embodiment, PPDUs of the first category and PPDUs of the second category may carry data frames comprising traffic of a first traffic type and traffic of a second traffic type. [0362] In an embodiment, the first traffic type may comprise low latency traffic or high-reliability traffic. In an embodiment, the first traffic type may comprise a first traffic identifier (TID). In an embodiment, the first traffic type may comprise a first traffic category (TC) or a first traffic stream (TS). In an embodiment, the first traffic type may comprise a first access category (AC). For example, the first AC may be associated with video (AC_VI) or voice (AC_VO). In another embodiment, the first traffic type may comprise a first stream classification service (SCS) stream. In another embodiment, the first traffic type may comprise a first SCS identifier (SCSID).

[0363] In an embodiment, the second traffic type may be different from the first traffic type. In an embodiment, the second traffic type may comprise a second TID. The second TID may be different from the first TID. In an embodiment, the second traffic type may comprise a second TC or a second TS. The second TC may be different from the first TC. The second TS may be different from the first TS. In an embodiment, the second traffic type may comprise a second AC. The second AC may be different from the first AC. In another embodiment, the second traffic type may comprise a second SCS stream. The second SCS stream may be different from the first SCS stream. In another embodiment, the second traffic type may comprise a second SCSID. The second SCSID may be different from the first SCSID.

[0364] In an implementation, while in the first power state/mode, STA 1902 is capable of receiving data frames carried by PPDUs of the first category. In an embodiment, STA 1902 may be capable of receiving traffic of the first traffic type and/or traffic of the second traffic type while operating in the first power state/mode. In an implementation, while STA 1902 operates in the first power state/mode, data frames carried by PPDUs of the first category may comprise traffic of the first traffic type or traffic of the second traffic type.

[0365] In an implementation, while in the second power state/mode, STA 1902 is capable of receiving data frames carried by PPDUs of the first category or the second category. In an embodiment, STA 1902 may be capable of receiving traffic of the first traffic type while operating in the second power state/mode. In an implementation, while STA 1902 operates in the second power state/mode, data frames carried by PPDUs of the first category or the second category may comprise traffic of the first traffic type. In another embodiment, STA 1902 may be capable of receiving traffic of the second traffic type while operating in the second power state/mode. In an implementation, while STA 1902 operates in the second power state/mode, data frames carried by PPDUs of the first category or the second category may comprise traffic of the second traffic type.

[0366] In an embodiment, before example 1900 begins, STA 1904 may initiate an SCS procedure with STA 1902. In an example, STA 1904 may transmit to STA 1902 an SCS request frame indicating the first SCSID (associated with traffic of the first traffic type). In an example, the SCS request frame may further indicate the second SCSID (associated with traffic of the second traffic type). In response, STA 1904 may receive an SCS response frame from STA 1904 indicating a first value associated with the first SCSI D. In an example, the SCS response frame may further indicate a second value associated with the second SCSID.

[0367] In an embodiment, STA 1902 may be configured to reserve the second power state/mode for receiving data frames satisfying a condition. In an embodiment, the data frames may comprise traffic of the first traffic type and/or the second traffic type. In an embodiment, the condition may be associated with a transmission duration/length of the data frames, or a queue size of BSR information of the data frames. This capability, in conjunction with the PS mode described above, may provide PS mode with traffic awareness capability that comprise a first capability and a second capability. For example, the second power state/mode may correspond to a high power receive state/mode with higher receive capabilities than the first power state/mode.

[0368] In an embodiment STA 1902 supports a first capability that allows/enables STA 1902 to perform the operations further described below. In an example, support of the first capability may allow STA 1902 to transmit to another STA a first frame indicating a condition that, when satisfied, the other STA is allowed to transmit to STA 1902 while STA 1902 operates in the second power state/mode. In an example, support of the first capability may further allow STA 1902 to receive from the other STA and while STA 1902 operates in the second power state/mode, a third frame comprising one or more first data frames satisfying the condition.

[0369] In an embodiment, STA 1904 supports a second capability that allows/enables STA 1904 to perform the operations further described below. In an example, support of the second capability may allow STA 1904 to receive from another STA a first frame indicating a condition that, when satisfied, STA 1904 is allowed to transmit to the other STA while the other STA operates in the second power state/mode of the PS mode. In an example, support of the second capability may further allow STA 1904 to receive from the other STA and while the other STA operates in the second power state/mode, the third frame comprising one or more first data frames satisfying the condition.

[0370] As shown in FIG. 19, the procedure illustrated in example 1900 may begin with STA 1902 transmitting a frame 1906 using EDCA during a first time period. In an embodiment, frame 1906 may indicate a condition that STA 1904 is allowed to transmit to STA 1902 while STA 1902 operates in the second power state/mode.

[0371] In an embodiment, the condition that, when satisfied, STA 1904 is allowed to transmit may comprise a first condition.

[0372] In an embodiment, STA 1904 may be allowed to transmit a first stream of frames to STA 1902 while STA 1902 operates in the second power state/mode, on condition that the first stream of frames satisfies the first condition.

[0373] In an embodiment, the first condition may comprise a first transmission duration of the first stream of frames being shorter than a first pre-determined duration. For example, the first pre-determined duration may comprise a maximum duration. For example, the first pre-determined duration maybe 100 pis or 1,000 pis.

[0374] In an embodiment, the first condition may comprise a first number of octets/bytes/bits of the first stream of frames being lower than a first pre-determined number of octets/bytes/bits. For example, the first pre-determined number may comprise a maximum number. For example, the first pre-determined number may be 100 bytes or 1 ,000 bytes.

[0375] In an embodiment, the first condition may comprise a first queue size of buffer status report (BSR) information of the first steam of frames being smaller than a first pre-determined queue size of BSR information. The first queue size of BSR information may indicate an amount of buffered traffic, in units of octets. For example, the first pre-determined queue size of BSR information may comprise a maximum queue size.

[0376] In another embodiment, the condition that, when satisfied, STA 1904 is allowed to transmit may comprise a second condition. In an embodiment, STA 1904 may be allowed to transmit a first stream of frames to STA 1902 while STA 1902 operates in the second power state/mode, on condition that the first stream of frames satisfies the second condition.

[0377] In an embodiment, the second condition may comprise a first transmission duration of the first stream of frames being longer than a second pre-determined duration. For example, the second pre-determined duration may comprise a minimum duration. For example, the second pre-determined duration may be 100 ps or 1,000 ps.

[0378] In an embodiment, the second condition may comprise a first number of octets/bytes/bits of the first stream of frames being lower than a second pre-determined number of octets/bytes/bits. For example, the second pre-determined number may comprise a minimum number. For example, the second pre-determined number may be 100 bytes or 1 ,000 bytes.

[0379] In an embodiment, the second condition may comprise a second queue size of BSR information of the first steam of frames being larger than a second pre-determined queue size of BSR information. The first queue size of BSR information may indicate an amount of buffered traffic, in units of octets. For example, the second pre-determined queue size of BSR information may comprise a maximum queue size.

[0380] In another embodiment, the condition that, when satisfied, STA 1904 is allowed to transmit may comprise both the first condition and the second condition.

[0381] In an embodiment, the first condition and/or the second condition may be indicated in frame 1906. In an embodiment, the first condition and/or the second condition may comprise a dynamic condition (e.g. , that may vary over time). The first condition and/or the second condition may thus be repeatedly signaled by STA 1902. In another embodiment, the first condition and/or the second condition may be a static condition (e.g., that does not vary over the time). The first condition and/or the second condition may thus be signaled only once by STA 1902 or may be preconfigured in STA 1902 and STA 1904.

[0382] In an embodiment, frame 1906 may further indicate a condition, that when unsatisfied by data frames (to be transmitted by STA 1904 to STA 1902), STA 1904 is not allowed to transmit to STA 1902 while STA 1902 operates in the second power state/mode. In an embodiment, the condition, that when unsatisfied by the data frames, STA 1904 is not allowed to transmit while STA 1902 operates in the second power state/mode may comprise the first condition and/or the second condition as described above.

[0383] In an embodiment, frame 1906 may comprise capability information of STA 1902 indicating support by STA 1902 of the first capability illustrated in FIG. 19. In an embodiment, frame 1906 may announce that STA 1902 is operating in the PS mode with traffic awareness. In an embodiment, STA 1902 may be operating in a default state/mode of the PS mode during the first time period. In an embodiment, the default state/mode may be the first power state/mode as described above. In another embodiment (not shown in FIG. 19), STA 1902 may operate in the other mode or in the second power state/mode of the PS mode and may transmit frame 1906 announcing that STA 1902 will operate in the PS mode in a future time period.

[0384] In an embodiment, frame 1906 may comprise a management frame indicating a broadcast address. In an example, frame 1906 may comprise a beacon frame. In another example, frame 1906 may comprise an action frame. [0385] STA 1904 may receive frame 1906 and may determine that STA 1902 is operating in the PS mode. As shown in FIG. 19, during the first time period, data may arrive at STA 1904 for transmission to STA 1902. In an example, the data may comprise traffic of the first traffic type and traffic of the second traffic type.

[0386] Based on receiving frame 1906, STA 1904 may match traffic buffered at STA 1904 to the condition indicated in frame 1906. In an embodiment, STA 1904 may prepare to transmit to STA 1902 a first stream of frames of the traffic satisfying the condition when STA 1902 transitions to the second power state/mode. The first stream of frames may comprise one or more first data frames (such as a MPDU 1912-1) carrying traffic of the first traffic type.

[0387] In an embodiment, where transmission of the first stream of frames to STA 1902 is based on the first stream of frames satisfying a first condition, STA 1904 may determine whether the first stream of frames satisfies the first condition. In another embodiment, where transmission of the first stream of frames to STA 1902 is based on the first stream of frames satisfying a second condition, STA 1904 may determine whether the first stream of frames satisfies the second condition.

[0388] In an embodiment, the first condition or the second condition is based on transmission duration. STA 1904 may determine whether a first transmission duration of the first stream of frames is shorter than a first pre-determined duration. In another embodiment, STA 1904 may determine whether a first transmission duration of the first stream of frames is longer than a second pre-determined duration. In an embodiment, the first transmission duration of the first stream of frames may correspond to a combined transmission duration of the one or more first data frames.

[0389] In an embodiment, the first condition or the second condition is based on transmission size. STA 1904 may determine whether a first number of octets/bytes/bits of the first stream of frames is lower than a first pre-determined number of octets/bytes/bits. In an embodiment, STA 1904 may determine whether a first number of octets/bytes/bits of the first stream of frames is higher than a second pre-determined number of octets/bytes/bits. In an embodiment, the first number of octets/bytes/bits of the first stream of frames may correspond to a total number of octets/bytes/bits of the one or more first data frames.

[0390] In another embodiment, the first condition is based on queue size of BSR. STA 1904 may determine whether a first queue size of the BSR information of the first stream of frames is lower than a first pre-determined queue size. In another embodiment, STA 1904 may determine whether a first queue size of the BSR information of the first stream of frames is higher than a second pre-determined queue size. In an embodiment, the first queue size of BSR information of the first stream of frames may correspond to a total queue size of BSR information of the one or more first data frames. [0391] As shown in FIG. 19, STA 1904 may have data arrival resulting in buffered traffic at STA 1904. In an example, an amount of the buffered traffic may comprise a first portion corresponding to the first stream of frames.

[0392] In an embodiment, before transmitting the first stream of frames to STA 1902, STA 1904 may perform EDCA and transmit to STA 1902, while STA 1902 operates in the first power state/mode, a frame 1908. In an embodiment, frame 1908 may request that STA 1902 transition from the first power state/mode to the second power state/mode to receive from STA 1904 a PPDU of the second category. [0393] In an embodiment, frame 1908 may indicate that the first stream of frames comprising traffic of the first traffic type and/or traffic of the first traffic type are to be transmitted after frame 1908 after STA 1902 transitions to the second power state/mode. In an embodiment, frame 1908 may further indicate a first transmission characteristic of the first stream of frames. In an example, the first transmission characteristic may comprise the first transmission duration of the first stream of frames. In an example, the first transmission characteristic may comprise the first number of octets/bytes/bits of the first stream of frames. In another example, the first transmission characteristic may comprise the first queue size of BSR information of the first stream of frames.

[0394] In an embodiment, frame 1908 may comprise a control frame. In an example, the control frame may comprise an ICF. In an example, the ICF may comprise an MU-RTS trigger frame or a BAR frame.

[0395] In an embodiment, STA 1902 may transition, in response to frame 1908, from the first power state/mode to the second power state/mode. As shown in FIG. 19, on receiving frame 1908 from STA 1904, STA 1902 may respond with an ICR 1910 and may initiate a transition from the first power state/mode to the second power state/mode at a time T1. In an embodiment, AP operates in the second power state/mode during a second time period. In an example, the second time period may begin at time T 1.

[0396] In an embodiment, STA 1902 may determine, from frame 1908, a TXOP duration, a bandwidth, and/or a modulation and coding scheme (MCS) of a PPDU carrying the first stream of frames of the first traffic type. STA 1902 may turn on/enable receiver capabilities based on the bandwidth and MCS indicated in frame 1908. In an implementation, STA 1902 may use the TXOP duration and the bandwidth indicated in frame 1908 to reserve a suitable channel for the PPDU. In an implementation, STA 1902 may perform a clear channel assessment (CCA) procedure over the channel to be used by STA 1904 for the transmission of the PPDU. After a successful CCA procedure, STA 1902 may transmit an ICR 1910 to STA 1904. ICR 1910 maybe configured to reserve the channel to be used by STA 1904 for the transmission of the PPDU. In an implementation, ICR 1910 may be a CTS frame that indicates the channel to be used by STA 1904 for the transmission of the PPDU.

[0397] On receiving ICR 1910, STA 1904 may initiate transmission of the PPDU carrying the first stream of frames. The PPDU may comprise the one or more first data frames (e.g„ MPDU 1912-1) that satisfies the condition indicated in frame 1906.

[0398] In an implementation, STA 1904 transmits the PPDU carrying the first stream of frames a SIFS after receiving ICR 1910. After receiving the PPDU, STA 1902 may transmit a BA frame 1914 to STA 1904. In an implementation, STA 1902 may return to the first power state/mode at a time T2 after receiving the PPDU. STA 1902 may transmit BA frame 1914 while in the second power state/mode or after returning to the first power state/mode. In an example, the second time period may be end at time T2.

[0399] In another example, the amount of buffered traffic resulting from data arrival at STA 1902 may further comprise a second portion corresponding to a second stream of frames. In an embodiment, the second stream of frames does not satisfy the first condition and/or the second condition. In an implementation, the second stream of frames may comprise one or more second data frames carrying traffic of the first traffic type and/or the second traffic type. [0400] As shown in FIG. 19, after time T2, STA 1904 may transmit to STA 1902 a second data frame (e.g., MPDU 1912-2). In an example, STA 1902 may receive the second data frame while operating in the first power state/mode. In another example, STA 1902 may receive the second data frame while operating in the other mode (not shown in FIG. 19).

[0401] In an embodiment (not shown in FIG. 19), STA 1904 may be configured to transmit to STA 1902, while STA 1902 operates in the first power state/mode, an amount of buffered traffic that does not satisfy the first condition and/or the second condition. In an embodiment, STA 1904 may be configured not to transmit to STA 1902, while STA 1902 operates in the second power state/mode, the amount of buffered traffic that does not satisfy the first condition and/or the second condition. In an example, STA 1904 may not transmit frame 1908 and receive frame 1910 for soliciting STA 1902 to transition from the first power state/mode to the second power state/mode.

[0402] As shown in FIG. 19, based on transmitting frame 1906, STA 1902 may transition from the first power state/mode to the second power state/mode only to receive from STA 1904 the first portion of buffered traffic that satisfies the condition. STA 1904 may only transmit to STA 1902 the first portion of buffered traffic that satisfies the condition while STA 1902 operates in the second power state/mode. In contrast, STA 1902 may receive the second portion of buffered traffic that does not satisfy the condition, when operating in the first power state/mode. This operation may enable STA 1902 to reduce the amount of time that STA 1902 operates in the second power state/mode, which reduces the overall power consumption of STA 1902. This operation may enable STA 1902 to reduce the amount of time that STA 1902 operates in the first power state/mode and to receive more data during the second power state/mode, which also reduces the overall power consumption of STA 1902.

[0403] In an embodiment, frame 1606 described in FIG. 16, frame 1706 described in FIG. 17, and frame 1806 described in FIG. 18 may be management frames, such as beacon frames or action frames.

[0404] FIG. 20 illustrates an example element 2000 which may be used in a management frame according to embodiments. The management frame may be a beacon frame or an action frame, for example. For example, the management frame may be an embodiment of frames 1606, 1706, and 1806.

[0405] In an embodiment, element 2000 may indicate a first traffic type that a first STA is allowed to transmit to a second STA while the second STA operates in a first power state/mode. The first STA may be an embodiment of STA 1604 described in FIG. 16, STA 1704 described in FIG. 17, or STA 1804 described in FIG. 18. The second STA may be an embodiment of STA 1602 described in FIG. 16, STA 1702 described in FIG. 17, or STA 1802 described in FIG. 18. The first power state/mode may be an embodiment of the second power state/mode described in FIGs. 16, 17, and 18. In another embodiment, element 2000 may indicate the first traffic type that the first STA is preferred/recommended to transmit to the second STA while the second STA operates in the first power state/mode.

[0406] In an embodiment, the management frame may include a frame body including element 2000. In an example, element 2000 may comprise a dynamic power save with traffic type awareness element. As shown in FIG. 20, element 2000 may include an element identifier (ID) field 2002, a length field, an element ID extension field, and an information field 2004. [0407] Element ID field 2002 may indicate an identifier of element 2000.

[0408] In an embodiment, information field 2004 may include a first allowed traffic type subfield 2006, an optional second allowed traffic type subfield 2008, and an optional priority information subfield 2010. In an embodiment, first allowed traffic type subfield 2006 may include a type information subfield 2012 and an optional condition information subfield 2014.

[0409] In an embodiment, type information subfield 2012 may include type information associated with the first traffic type that the first STA is allowed to transmit to the second STA while the second STA operates in the first power state/mode. The first traffic type may be as described in example 1600, 1700, or 1800. The type information may comprise a first traffic identifier (TID), a first traffic category (TC), a first traffic stream (TS), a first access category (AC), a first SCS stream, or a first SCSID of the first traffic type.

[0410] In an embodiment, condition information subfield 2014 may include a first condition associated with the first traffic type indicated in type info subfield 2012. In an embodiment, the first condition may be an embodiment of the first condition described in examples 1600 and 1700 above.

[0411] In an embodiment, similar to first allowed traffic type subfield 2006, second allowed traffic type subfield 2008 may include a type information subfield and a condition information subfield, associated with a second traffic type that the first STA is allowed to transmit to the second STA while the second STA operates in the first power state/mode. The first traffic type may be as described in example 1700.

[0412] In an embodiment, priority information subfield 2010 may include a first priority and a second priority. In an embodiment, the first priority may be associated with the first traffic type. In an example, the first priority may comprise an embodiment of the first priority described in example 1700. In an embodiment, the second priority may be associated with the second traffic type. In an example, the second priority may comprise an embodiment of the second priority described in example 1700.

[0413] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to cases including more than two STAs.

[0414] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to cases including more than two APs.

[0415] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to scenarios in which any of the APs or any of the STAs may comprise a MLD, comprising at least one affiliated AP or affiliated STA.

[0416] FIG. 21 illustrates an example process 2100 according to an embodiment of the present disclosure. Example process 2100 is provided for the purpose of illustration only and is not limiting of embodiments. Example process 2100 may be performed by a first STA such as STA 1602, STA 1702, or STA 1802, for example. Process 2100 may be performed while the first STA is in a power save mode as illustrated in FIGs. 16-18, for example. The power save mode may comprise a low-power listening mode or a dynamic power save mode. The power save mode may comprise a first power state/mode and a second power state/mode as described above. The first power state/mode may comprise a high power receive state/mode or an awake state/mode of the power save mode. The second power state/mode may comprise a low power receive state/mode or a listen/listening state/mode of the power save mode.

[0417] As shown in FIG.21 , process 2100 begins in step 2102, which includes transmitting, by the first STA to a second STA, a first frame indicating a first traffic type that the second STA is allowed to transmit to the first STA while the first STA operates in a first power state/mode of a power save mode. For example, the second STA may be a STA such as STA 1604, STA 1704, or STA 1804.

[0418] In an embodiment, the first traffic type comprises a first traffic identifier, a first traffic category, a first traffic stream, a first access category, a first stream classification service stream, or a first stream classification service identifier. [0419] In an embodiment, the first STA is capable of receiving traffic of the first traffic type while operating in the first power state/mode. In an embodiment, the first STA is not capable of receiving traffic of the first traffic type while operating in the second power state/mode. In an embodiment, the first traffic type comprises low latency traffic or high reliability traffic.

[0420] In an embodiment, the first frame further indicates the first traffic type that the first STA prefers to receive while the first STA operates in the first power state/mode of the power save mode.

[0421] In an embodiment, the second STA is allowed to transmit a first stream of frames of the first traffic type to the first STA while the first STA operates in the first power state/mode, on condition that the first stream of frames satisfies a first condition.

[0422] In an embodiment, the first condition comprises a first transmission duration of the first stream of frames being shorter than a first pre-determined duration. In an embodiment, the first condition comprises a first transmission duration of the first stream of frames being longer than a second pre-determined duration. In an embodiment, the first condition comprises a first number of octets/bytes/bits of the first stream of frames being lower than a first pre-determined number of octets/bytes/bits. In an embodiment, the first condition comprises a first number of octets/bytes/bits of the first stream of frames being higher than a second pre-determined number of octets/bytes/bits. In an embodiment, the first condition is indicated in the first frame or pre-configured.

[0423] In an embodiment, the first frame further indicates a second traffic type that the second STA is not allowed to transmit to the first STA while the first STA operates in the first power state/mode.

[0424] In an embodiment, the first frame further indicates a second traffic type that the second STA is allowed to transmit to the first STA while the first STA operates in the first power state/mode.

[0425] In an embodiment, the second traffic type comprises a second traffic identifier, a second traffic category, a second traffic stream, a second access category, a second stream classification service stream, or a second stream classification service identifier.

[0426] In an embodiment, the first traffic type is associated with a first priority for transmission of traffic of the first traffic type, by the second STA to the first STA, while the first STA operates in the first power state/mode. In an embodiment, the second traffic type is associated with a second priority for transmission of traffic of the second traffic type, by the second STA to the first STA, while the first STA operates in the first power state/mode. In an embodiment, the first priority is higher than the second priority. In an embodiment, the first frame indicates the first priority and the second priority.

[0427] In an embodiment, the second STA is allowed to transmit a second stream of frames of the second traffic type to the first STA while the first STA operates in the first power state/mode, on condition that the second stream of frames satisfies a second condition.

[0428] In an embodiment, the second condition comprises a second transmission duration of the second steam of frames being shorter than a third pre-determined duration. In an embodiment, the second condition comprises a second transmission duration of the second steam of frames being longer than a fourth pre-determined duration. In an embodiment, the second condition comprises a second number of octets/bytes/bits of the second stream of frames being lower than a third pre-determined number of octets/bytes/bits. In an embodiment, the second condition comprises a second number of octets/bytes/bits of the second stream of frames being higher than a fourth pre-determined number of octets/bytes/bits In an embodiment, the second condition is indicated in the first frame or pre-configured.

[0429] In step 2104, process 2100 includes receiving, by the first STA from the second STA and while the first STA operates in a second power state/mode of the power save mode, a second frame.

[0430] In an embodiment, the first STA is not capable of receiving the traffic of the first traffic type while operating in the second power state/mode.

[0431] In an embodiment, the first STA is capable of transitioning between the first power state/mode and the second power state/mode of the power save mode.

[0432] In an embodiment, process 2100 may further comprise transitioning, by the first STA and in response to the second frame, from the second power state/mode to the first power state/mode.

[0433] In step 2106, process 2100 includes receiving, by the first STA from the second STA and while the first STA operates in the first power state/mode, a third frame comprising one or more first data frames of the first traffic type. In an embodiment, the one or more data frames comprised in the third frame satisfy the first condition. In an embodiment, the third frame further comprises one or more second data frames of the second traffic type. In an embodiment, the one or more data frames comprised in the third frame satisfy the second condition.

[0434] FIG. 22 illustrates an example process 2200 according to an embodiment of the present disclosure. Example process 2200 is provided for the purpose of illustration only and is not limiting of embodiments. Example process 2200 may be performed by a first STA such as STA 1604, STA 1704, or STA 1804, for example.

[0435] As shown in FIG.22, process 2200 begins in step 2202, which includes receiving, by the first STA from a second STA, a first frame indicating a first traffic type that the first STA is allowed to transmit to the second STA while the second STA operates in a first power state/mode of a power save mode. For example, the second STA may be an STA such as STA 1602, STA 1702, or STA 1802. The power save mode may be a power save mode as illustrated in FIGs. 16-18 herein. The power save mode may comprise a low-power listening mode or a dynamic power save mode. The power save mode may comprise a first power state/mode and a second power state/mode as described above. The first power state/mode may comprise a high power receive state/mode or an awake state/mode of the power save mode. The second power state/mode comprises a low power receive state/mode or a listen/listening state/mode of the power save mode. [0436] In an embodiment, the first traffic type comprises a first traffic identifier, a first traffic category, a first traffic stream, a first access category, a first stream classification service stream, or a first stream classification service identifier. [0437] In an embodiment, the second STA is capable of receiving traffic of the first traffic type while operating in the first power state/mode. In an embodiment, the second STA is not capable of receiving traffic of the first traffic type while operating in the second power state/mode. In an embodiment, the first traffic type comprises low latency traffic or high reliability traffic.

[0438] In an embodiment, the first frame further indicates the first traffic type that the second STA prefers to receive while the second STA operates in the first power state/mode of the power save mode.

[0439] In an embodiment, the first STA is allowed to transmit a first stream of frames of the first traffic type to the second STA while the second STA operates in the first power state/mode, on condition that the first stream of frames satisfies a first condition.

[0440] In an embodiment, the first condition comprises a first transmission duration of the first stream of frames being shorter than a first pre-determined duration. In an embodiment, the first condition comprises a first number of octets/bytes/bits of the first stream of frames being lower than a first pre-determined number of octets/bytes/bits. In an embodiment, the first condition is indicated in the first frame or pre-configured.

[0441] In an embodiment, the first frame further indicates a second traffic type that the first STA is not allowed to transmit to the second STA while the second STA operates in the first power state/mode.

[0442] In an embodiment, the first frame further indicates a second traffic type that the first STA is allowed to transmit to the second STA while the second STA operates in the first power state/mode.

[0443] In an embodiment, the second traffic type comprises a second traffic identifier, a second traffic category, a second traffic stream, a second access category, a second stream classification service stream, or a second stream classification service identifier.

[0444] In an embodiment, the first traffic type is associated with a first priority for transmission of traffic of the first traffic type, by the first STA to the second STA, while the second STA operates in the first power state/mode. In an embodiment, the second traffic type is associated with a second priority for transmission of traffic of the second traffic type, by the first STA to the second STA, while the second STA operates in the first power state/mode. In an embodiment, the first priority is higher than the second priority.

[0445] In an embodiment, the first frame indicates the first priority and the second priority.

[0446] In an embodiment, the first STA is allowed to transmit a second stream of frames of the second traffic type to the second STA while the second STA operates in the first power state/mode, on condition that the second stream of frames satisfies a second condition.

[0447] In an embodiment, the second condition comprises a second transmission duration of the second steam of frames being shorter than a second pre-determined duration. In an embodiment, the second condition comprises a second number of octets/bytes/bits of the second stream of frames being lower than a second pre-determined number of octets/bytes/bits. In an embodiment, the second condition is indicated in the first frame or pre-configured.

[0448] In step 2204, process 2200 includes transmitting, by the first STA to the second STA and while the second STA operates in the first power state/mode, a second frame comprising one or more data frames of the first traffic type. In an embodiment, the one or more first data frames comprised in the second frame satisfy the first condition. In an embodiment, the second frame further comprises one or more second data frames of the second traffic type. In an embodiment, the one or more second data frames comprised in the second frame satisfy the second condition.

[0449] In an embodiment, process 2200 may further comprise transmitting, by the first STA to the second STA and while the second STA operates in the second power state/mode of the power save mode, a third frame; and receiving, by the first STA from the second STA, a response to the third frame. In an embodiment, the second STA is not capable of receiving the traffic of the first traffic type while operating in the second power state/mode.

[0450] In another embodiment, a first STA may perform a process comprising transmitting, by the first STA to a second STA, a first frame indicating a preferred/recommended traffic type that the first STA prefers to receive while the first STA operates in a first power state/mode of a power save mode; receiving, by the first STA, from the second STA and while the first STA operates in a second power state/mode of the power save mode, a second frame; transitioning, by the first STA and in response to the second frame, from the second power state/mode to the first power state/mode; and receiving, by the first STA from the second STA and while the first STA operates in the first power state/mode, a third frame comprising one or more first data frames of the preferred/recommended traffic type. The power save mode may comprise a low-power listening mode or a dynamic power save mode. The first power state/mode may comprise a high power receive state/mode or an awake state/mode of the power save mode. The second power state/mode may comprise a low power receive state/mode or a listening state/mode of the power save mode.

[0451] In another embodiment, a first STA may perform a process comprising receiving, by the first STA from a second STA and while the first STA operates in a first power state/mode of a power save mode, a first frame; transitioning, by the first STA and in response to the first frame, from the first power state/mode to a second power state/mode of the power save mode; and receiving, by the first STA from the second STA and while the first STA operates in the second power state/mode, a second frame comprising one or more first data frames of a first traffic type. The second STA may be configured to transmit to the first STA, while the first STA operates in the second power state/mode, traffic of the first traffic type. In an embodiment, the second STA may be configured not to transmit to the first STA, while the first STA operates in the second power state/mode, traffic of a second traffic type. The power save mode may comprise a low- power listening mode or a dynamic power save mode. The first power state/mode may comprise a low power receive state/mode or a listening state/mode of the power save mode. The second power state/mode may comprise a high power receive state/mode or an awake state/mode of the power save mode.

[0452] In another embodiment, a first STA may perform a process comprising receiving, by the first STA from a second STA, a first frame indicating a preferred/recommended traffic type that the second STA prefers to receive while the second STA operates in a first power state/mode of a power save mode; transmitting, by the first STA, to the second STA and while the second STA operates in a second power state/mode of the power save mode, a second frame; receiving, by the first STA from the second STA, a response to the second frame; and transmitting, by the first STA to the second STA and while the second STA operates in the first power state/mode, a third frame comprising one or more first data frames of the preferred/recommended traffic type. The power save mode may comprise a low-power listening mode or a dynamic power save mode. The first power state/mode may comprise a high power receive state/mode or an awake state/mode of the power save mode. The second power state/mode may comprise a low power receive state/mode or a listening state/mode of the power save mode.

[0453] In another embodiment, a first STA may perform a process comprising transmitting, by the first STA to a second STA and while the second STA operates in a first power state/mode of a power save mode, a first frame; receiving, by the first STA from the second STA, a response to the first frame; and transmitting, by the first STA to the second STA while the second STA operates in a second power state/mode of the power save mode, a second frame comprising one or more first data frames of a first traffic type. The first STA may be configured to transmit to the second STA, while the second STA operates in the second power state/mode, traffic of the first traffic type. In an embodiment, the first STA may be configured not to transmit to the second STA, while the second STA operates in the second power state/mode, traffic of a second traffic type. The power save mode may comprise a low-power listening mode or a dynamic power save mode. The first power state/mode may comprise a low power receive state/mode or a listening state/mode of the power save mode. The second power state/mode may comprise a high power receive state/mode or an awake state/mode of the power save mode.

Claims

CLAIMS What is claimed is:

1. A method comprising: transmitting, by a first station (STA) to a second STA, a first frame indicating a first traffic type that the second STA is allowed to transmit to the first STA while the first STA operates in a first power mode of a power save mode; receiving, by the first STA from the second STA and while the first STA operates in a second power mode of the power save mode, a second frame; transitioning, by the first STA and in response to the second frame, from the second power mode to the first power mode; and receiving, by the first STA from the second STA and while the first STA operates in the first power mode, a third frame comprising one or more first data frames of the first traffic type.

2. A method comprising: transmitting, by a first station (STA) to a second STA, a first frame indicating a first traffic type that the second STA is allowed to transmit to the first STA while the first STA operates in a first power mode of a power save mode; receiving, by the first STA from the second STA and while the first STA operates in a second power mode of the power save mode, a second frame; and receiving, by the first STA from the second STA and while the first STA operates in the first power mode, a third frame comprising one or more first data frames of the first traffic type.

3. The method of claim 2, further comprising: transitioning, by the first STA and in response to the second frame, from the second power mode to the first power mode.

4. The method of any of claims 2-3, wherein the first traffic type comprises a first traffic identifier, a first traffic category, a first traffic stream, a first access category, a first SCS stream, or a first stream classification service identifier.

5. The method of any of claims 2-4, wherein the first STA is capable of receiving traffic of the first traffic type while operating in the first power mode.

6. The method of claim 5, wherein the first STA is not capable of receiving the traffic of the first traffic type while operating in the second power mode.

7. The method of any of claims 2-6, wherein the first traffic type comprises low latency traffic or high reliability traffic.

8. The method of any of claims 2-7, wherein the first frame further indicates the first traffic type that the first STA prefers to receive while the first STA operates in the first power mode of the power save mode.

9. The method of any of claims 2-8, wherein the second STA is allowed to transmit a first stream of frames of the first traffic type to the first STA while the first STA operates in the first power mode, on condition that the first stream of frames satisfies a first condition.

10. The method of claim 9, wherein the first condition comprises a first transmission duration of the first stream of frames being shorter than a first pre-determined duration.

11. The method of claim 9, wherein the first condition comprises a first transmission duration of the first stream of frames being longer than a second pre-determined duration.

12. The method of claim 9, wherein the first condition comprises a first number of octets/bytes/bits of the first stream of frames being lower than a first pre-determined number of octets/bytes/bits.

13. The method of claim 9, wherein the first condition comprises a first number of octets/bytes/bits of the first stream of frames being higher than a second pre-determined number of octets/bytes/bits.

14. The method of any of claims 9-13, wherein the first condition is indicated in the first frame or pre-configured.

15. The method of any of claims 9-14, wherein the one or more data frames comprised in the third frame satisfy the first condition.

16. The method of any of claims 3-15, wherein the first frame further indicates a second traffic type that the second STA is not allowed to transmit to the first STA while the first STA operates in the first power mode.

17. The method of any of claims 3-15, wherein the first frame further indicates a second traffic type that the second STA is allowed to transmit to the first STA while the first STA operates in the first power mode.

18. The method of claim 17, wherein the second traffic type comprises a second traffic identifier (TID), a second traffic category (TC), a second traffic stream (TS), a second access category (AC), a second SCS stream, or a second stream classification service identifier (SCSID).

19. The method of any of claims 17-18, wherein the first traffic type is associated with a first priority for transmission of traffic of the first traffic type, by the second STA to the first STA, while the first STA operates in the first power mode.

20. The method of claim 19, wherein the second traffic type is associated with a second priority for transmission of traffic of the second traffic type, by the second STA to the first STA, while the first STA operates in the first power mode.

21. The method of claim 20, wherein the first priority is higher than the second priority.

22. The method of any of claims 20-21, wherein the first frame indicates the first priority and the second priority.

23. The method of any of claims 17-22, wherein the second STA is allowed to transmit a second stream of frames of the second traffic type to the first STA while the first STA operates in the first power mode, on condition that the second stream of frames satisfies a second condition.

24. The method of claim 23, wherein the second condition comprises a second transmission duration of the second stream of frames being shorter than a third pre-determined duration.

25. The method of claim 23, wherein the second condition comprises a second transmission duration of the second stream of frames being higher than a fourth pre-determined duration.

26. The method of claim 23, wherein the second condition comprises a second number of octets/bytes/bits of the second stream of frames being lower than a third pre-determined number of octets/bytes/bits.

27. The method of claim 23, wherein the second condition comprises a second number of octets/bytes/bits of the second stream of frames being higher than a fourth pre-determined number of octets/bytes/bits.

28. The method of any of claims 23-27, wherein the second condition is indicated in the first frame or pre-configured.

29. The method of any of claims 17-28, wherein the third frame further comprises one or more second data frames of the second traffic type.

30. The method of claim 28, wherein the one or more second data frames comprised in the third frame satisfy the second condition.

31. The method of any of claims 2-30, wherein the power save mode comprises a low-power listening mode or a dynamic power save mode.

32. The method of any of claims 2-31, wherein the first power mode comprises a higher capability mode, a higher power receive mode, or an awake mode of the power save mode.

33. The method of claim 32, wherein the second power mode comprises a lower capability mode, a lower power receive mode, or a listen mode of the power save mode.

34. A method comprising: receiving, by a first station (STA) to a second STA, a first frame indicating a first traffic type that the first STA is allowed to transmit to the second STA while the second STA operates in a first power mode of a power save mode; and transmitting, by the first STA to the second STA and while the second STA operates in the first power mode, a second frame comprising one or more data frames of the first traffic type.

35. The method of claim 34, wherein the first traffic type comprises a first traffic identifier, a first traffic category, a first traffic stream, a first access category, a first SCS stream, or a first stream classification service identifier.

36. The method of any of claims 34-35, wherein the first STA is capable of receiving traffic of the first traffic type while operating in the first power mode.

37. The method of claim 36, wherein the first STA is not capable of receiving the traffic of the first traffic type while operating in the second power mode.

38. The method of any of claims 34-37, wherein the firsttraffic type comprises low latency traffic or high reliability traffic.

39. The method of any of claims 34-38, wherein the first frame further indicates the first traffic type that the first STA prefers to receive while the first STA operates in the first power mode of the power save mode.

40. The method of any of claims 34-39, wherein the first STA is allowed to transmit a first stream of frames of the first traffic type to the second STA while the second STA operates in the first power mode, on condition that the first stream of frames satisfies a first condition.

41. The method of claim 40, wherein the first condition comprises a first transmission duration of the first stream of frames being shorter than a first pre-determined duration.

42. The method of claim 40, wherein the first condition comprises a first transmission duration of the first stream of frames being longer than a second pre-determined duration.

43. The method of claim 40, wherein the first condition comprises a first number of octets/bytes/bits of the first stream of frames being lower than a first pre-determined number of octets/bytes/bits.

44. The method of claim 40, wherein the first condition comprises a first number of octets/bytes/bits of the first stream of frames being higher than a second pre-determined number of octets/bytes/bits.

45. The method of any of claims 40-44, wherein the first condition is indicated in the first frame or pre-configured.

46. The method of any of claims 40-45, wherein the one or more data frames comprised in the second frame satisfy the first condition.

47. The method of any of claims 34-46, wherein the first frame further indicates a second traffic type that the first STA is not allowed to transmit to the second STA while the second STA operates in the first power mode.

48. The method of any of claims 34-46, wherein the first frame further indicates a second traffic type that the first STA is allowed to transmit to the second STA while the second STA operates in the first power mode.

49. The method of claim 48, wherein the second traffic type comprises a second traffic identifier (TID), a second traffic category (TC), a second traffic stream (TS), a second access category (AC), a second SCS stream, or a second stream classification service identifier (SCSID).

50. The method of any of claims 48-49, wherein the first traffic type is associated with a first priority for transmission of traffic of the first traffic type, by the first STA to the second STA, while the second STA operates in the first power mode.

51. The method of claim 50, wherein the second traffic type is associated with a second priority for transmission of traffic of the second traffic type, by the first STA to the second STA, while the second STA operates in the first power mode.

52. The method of claim 51 , wherein the first priority is higher than the second priority.

53. The method of any of claims 51-52, wherein the first frame indicates the first priority and the second priority.

54. The method of any of claims 47-53, wherein the first STA is allowed to transmit a second stream of frames of the second traffic type to the second STA while the second STA operates in the first power mode, on condition that the second stream of frames satisfies a second condition.

55. The method of claim 54, wherein the second condition comprises a second transmission duration of the second stream of frames being shorter than a third pre-determined duration.

56. The method of claim 54, wherein the second condition comprises a second transmission duration of the second stream of frames being higher than a fourth pre-determined duration.

57. The method of claim 54, wherein the second condition comprises a second number of octets/bytes/bits of the second stream of frames being lower than a third pre-determined number of octets/bytes/bits.

58. The method of claim 54, wherein the second condition comprises a second number of octets/bytes/bits of the second stream of frames being higher than a fourth pre-determined number of octets/bytes/bits.

59. The method of any of claims 54-58, wherein the second condition is indicated in the first frame or pre-configured.

60. The method of any of claims 54-59, wherein the second frame further comprises one or more second data frames of the second traffic type.

61. The method of claim 60, wherein the one or more second data frames comprised in the second frame satisfy the second condition.

62. The method of any of claims 34-61, wherein the power save mode comprises a low-power listening mode or a dynamic power save mode.

63. The method of any of claims 34-62, wherein the first power mode comprises a higher capability mode, a higher power receive mode, or an awake mode of the power save mode.

64. The method of claim 63, wherein the second power mode comprises a lower capability mode, a lower power receive mode, or a listen mode of the power save mode.

65. A device comprising: one or more processors; and memory storing instructions that, when executed by the one or more processors, cause the device to perform a method according to any of claims 1-64.

66. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors, cause the one or more processors to perform a method according to any of claims 1-64.