WO2020139002A1 - Method and device for transmitting broadcast frame in wireless lan system - Google Patents

Abstract

A method and a device for transmitting a broadcast frame to a wireless LAN system are presented. Particularly, a transmitting STA having a multiple BSSID generates a broadcast frame and transmits the broadcast frame to a receiving STA. The multiple BSSID includes a first BSSID and a second BSSID. The first BSSID is an identifier of a first BSS that transmits a beacon frame. The second BSSID is an identifier of a second BSS excluding the first BSS in all BSSs mapped to the multiple BSSID. The broadcast frame includes an ID field. The ID field is set to an ID for all of the BSSs. IDs for all of the BSSs are acquired on the basis of a transmission end ID for identifying the transmitting STA. The transmission ID is acquired on the basis of the first BSSID.

Description

Method and apparatus for transmitting broadcast frame in wireless LAN system

The present specification relates to a technique for performing low-power communication in a wireless LAN system, and more particularly, to a method and apparatus for transmitting a broadcast frame in a wireless LAN system.

The wireless local area network (WLAN) has been improved in various ways. For example, the IEEE 802.11ax standard proposed an improved communication environment using orthogonal frequency division multiple access (OFDMA) and downlink multi-user multiple input (MIMO) techniques.

This specification proposes technical features that can be used in new communication standards. For example, the new communication standard may be an extreme high throughput (EHT) standard currently being discussed. The EHT standard can use the newly proposed increased bandwidth, improved PHY layer protocol data unit (PPDU) structure, improved sequence, and hybrid automatic repeat request (HARQ) technique. The EHT standard may be referred to as the IEEE 802.11be standard.

In the new WLAN standard, an increased number of spatial streams can be used. In this case, in order to properly use the increased number of spatial streams, the signaling technique in the WLAN system may need to be improved.

This specification proposes a method and apparatus for transmitting a broadcast frame in a wireless LAN system.

An example of the present specification proposes a method and apparatus for transmitting a broadcast frame in a wireless LAN system.

This embodiment can be performed in a network environment in which a next generation wireless LAN system is supported. The next-generation wireless LAN system is an improved wireless LAN system that can satisfy backward compatibility with the 802.11ax system.

This embodiment is performed by a transmitting STA, and the transmitting STA may correspond to an Extremely High Throughput (EHT) access point (AP) or a Wake Up Radio (WUR) AP. The receiving STA of this embodiment may correspond to an EHT STA or WUR STA.

The transmitting STA (station) having multiple BSSIDs (Multiple Basic Service Set IDentification) generates the broadcast frame. The broadcast frame may be a broadcast wake up frame, and in the embodiments herein, the broadcast frame will be described assuming a broadcast wake up frame unless otherwise specified.

The transmitting STA transmits the broadcast frame to the receiving STA.

The multiple BSSIDs include a first BSSID and a second BSSID.

The first BSSID is an identifier of a first BSS that transmits a beacon frame. The first BSSID may correspond to a Transmitted BSSID.

The second BSSID is an identifier of a second BSS except for the first BSS in all BSSs mapped to the multiple BSSIDs. The second BSSID may correspond to a nontransmitted BSSID.

Conventionally, in order to wake up the receiving STAs belonging to all BSSs mapped to the multiple BSSIDs, the transmitting STA includes each ID (the first BSSID or the second BSSID) corresponding to each of the BSSs in a wake-up frame. There has been a problem in that the WSS frame has to be repeatedly transmitted multiple times for the BSS.

In contrast, this embodiment proposes a method for a transmitting STA having multiple BSSIDs to wake up receiving STAs belonging to all BSSs mapped to multiple BSSIDs at once by transmitting a broadcast frame. The proposed method is as follows.

The broadcast frame includes an ID (IDentification) field.

The ID field is set to IDs for all the BSSs.

IDs for all the BSSs are obtained based on a transmitter ID identifying the transmitting STA.

The transmitter ID is obtained based on the first BSSID.

According to the embodiment proposed in the present specification, by setting the ID field of the broadcast frame to IDs for all BSSs, the transmitting STA is a resource generated by transmitting a specific BSS broadcast frame multiple times with one broadcast frame transmission It is possible to reduce waste, and in particular, when the corresponding broadcast frame is a broadcast wake-up frame, it is possible to efficiently wake up the receiving STAs belonging to all BSSs at once.

1 is a conceptual diagram showing the structure of a wireless local area network (WLAN).

2 is a diagram showing an example of a PPDU used in the IEEE standard.

3 is a view showing an example of the HE PPDU.

4 is a view showing a low-power wake-up receiver in an environment in which no data is received.

5 is a view showing a low-power wake-up receiver in an environment in which data is received.

6 shows an example of a wakeup packet structure according to the present embodiment.

7 shows a signal waveform of a wake-up packet according to the present embodiment.

FIG. 8 is a diagram for explaining a principle in which power consumption is determined according to a ratio of 1 to 0 of bit values constituting binary sequence information using an OOK method.

9 shows a method of designing an OOK pulse according to the present embodiment.

10 shows an example of a transmitting device and/or a receiving device of the present specification.

11 is a diagram for explaining a general link setup process.

12 is a diagram showing an example of a PPDU used in the IEEE standard.

13 shows an example of a PPDU used in the present specification.

14 shows an example of the format of multiple BSSID elements.

15 shows an example of a multiple BSSID-Index element format.

16 shows an example of the WUR frame format.

17 shows an example of a Frame Control field format.

18 shows an example of a Type Dependent Control field format.

19 shows an example of a miscellaneous subfield format.

20 is a flowchart illustrating a procedure for transmitting a broadcast frame in a transmitting STA according to the present embodiment.

21 is a flowchart illustrating a procedure for receiving a broadcast frame at a receiving STA according to the present embodiment.

22 shows a more detailed wireless device implementing an embodiment of the present invention.

1 is a conceptual diagram showing the structure of a wireless local area network (WLAN).

The top of FIG. 1 shows the structure of an infrastructure basic service set (BSS) of the Institute of Electrical and Electronic Engineers (IEEE) 802.11.

Referring to the top of FIG. 1, the wireless LAN system may include one or more infrastructure BSSs 100 and 105 (hereinafter, BSS). The BSS (100, 105) is a set of APs and STAs such as an access point (AP) 125 and an STA1 (Station 100-1) that can successfully communicate with each other through synchronization, and does not indicate a specific area. The BSS 105 may include one or more combineable STAs 105-1 and 105-2 in one AP 130.

The BSS may include at least one STA, APs 125 and 130 providing a distributed service, and a distributed system (DS, 110) connecting multiple APs.

The distributed system 110 may connect multiple BSSs 100 and 105 to implement an extended service set (ESS) 140. The ESS 140 may be used as a term indicating one network in which one or more APs 125 and 230 are connected through the distributed system 110. APs included in one ESS 140 may have the same service set identification (SSID).

The portal 120 may serve as a bridge that performs a connection between a WLAN network (IEEE 802.11) and another network (eg, 802.X).

In the BSS such as the top of FIG. 1, a network between APs 125 and 130 and a network between APs 125 and 130 and STAs 100-1, 105-1, and 105-2 may be implemented. However, it may be possible to perform communication by setting a network even between STAs without APs 125 and 130. A network that establishes a network even between STAs without APs 125 and 130 to perform communication is defined as an ad-hoc network or an independent basic service set (BSS).

1 is a conceptual diagram showing the IBSS.

1, the IBSS is a BSS operating in an ad-hoc mode. Since IBSS does not include an AP, there is no centralized management entity performing central management functions. That is, STAs 150-1, 150-2, 150-3, 155-4, and 155-5 in the IBSS are managed in a distributed manner. In IBSS, all STAs (150-1, 150-2, 150-3, 155-4, 155-5) may be made of mobile STAs, and access to a distributed system is not allowed, so a self-contained network (self-contained) network).

STA is any functional medium including a medium access control (MAC) and a physical layer interface to a wireless medium in accordance with the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. Can be used as a meaning including both an AP and a non-AP STA (Non-AP Station).

STA includes a mobile terminal, a wireless device, a wireless transmit/receive unit (WTRU), user equipment (UE), a mobile station (MS), and a mobile subscriber unit ( Mobile Subscriber Unit) or simply a user (user).

Meanwhile, the term user may be used in various meanings, and may also be used to mean an STA participating in uplink MU MIMO and/or uplink OFDMA transmission in wireless LAN communication, for example. It is not limited thereto.

2 is a diagram showing an example of a PPDU used in the IEEE standard.

As illustrated, various types of PHY protocol data units (PPDUs) have been used in standards such as IEEE a/g/n/ac. Specifically, the LTF and STF fields included training signals, and SIG-A and SIG-B included control information for the receiving station, and data fields included user data corresponding to PSDU.

This embodiment proposes an improved technique for the signal (or control information field) used for the data field of the PPDU. The signal proposed in this embodiment may be applied on a high efficiency PPDU (HE PPDU) according to the IEEE 802.11ax standard. That is, the signal to be improved in this embodiment may be HE-SIG-A and/or HE-SIG-B included in the HE PPDU. Each of HE-SIG-A and HE-SIG-B can also be marked as SIG-A, SIG-B. However, the improved signal proposed by the present embodiment is not necessarily limited to the HE-SIG-A and/or HE-SIG-B standards, and control of various names including control information in a wireless communication system for transmitting user data/ Applicable to data fields.

3 is a view showing an example of the HE PPDU.

The control information field proposed in this embodiment may be HE-SIG-B included in the HE PPDU as shown in FIG. 3. The HE PPDU according to FIG. 3 is an example of a PPDU for multiple users, and HE-SIG-B is included only for multiple users, and the corresponding HE-SIG-B may be omitted from the PPDU for a single user.

As shown, HE-PPDU for multiple users (MU) is a legacy-short training field (L-STF), legacy-long training field (L-LTF), legacy-signal (L-SIG), High efficiency-signal A (HE-SIG-A), high efficiency-signal-B (HE-SIG-B), high efficiency-short training field (HE-STF), high efficiency-long training field (HE-LTF) , Data field (or MAC payload) and PE (Packet Extension) field. Each field may be transmitted during the illustrated time period (ie, 4 or 8 ms, etc.).

The PPDU used in the IEEE standard is mainly described as a PPDU structure transmitted on a channel bandwidth of 20 MHz. The PPDU structure transmitted on a wider bandwidth (for example, 40 MHz, 80 MHz) than the channel bandwidth of 20 MHz may be a structure in which linear scaling is applied to the PPDU structure used in the channel bandwidth of 20 MHz.

The PPDU structure used in the IEEE standard is generated based on 64 Fast Fourier Tranforms (FFTs), and a CP portion (cyclic prefix portion) may be 1/4. In this case, the length of the effective symbol period (or FFT period) may be 3.2us, the CP length of 0.8us, and the symbol duration may be 4us (3.2us+0.8us) plus the effective symbol period and the CP length.

Wireless networks are ubiquitous, usually indoors and frequently installed outdoors. Wireless networks transmit and receive information using a variety of techniques. For example, but not limited to, two widely used technologies used for communication are technologies that comply with IEEE 802.11 standards such as the IEEE 802.11n standard and IEEE 802.11ac standard.

The IEEE 802.11 standard specifies a common medium access control (MAC) layer that provides various functions to support the operation of IEEE 802.11-based wireless LANs (WLANs). The MAC layer utilizes protocols that coordinate access to shared radios and enhance communication over wireless media, such as IEEE 802.11 stations (such as a PC's wireless network card (NIC) or other wireless device or station (STA) and access point ( AP)).

IEEE 802.11ax is a successor to 802.11ac and has been proposed to increase the efficiency of WLAN networks, especially in high-density areas such as public hotspots and other high-density traffic areas. IEEE 802.11 can also use orthogonal frequency division multiple access (OFDMA). The High Efficiency WLAN Research Group (HEW SG) within the IEEE 802.11 Work Group is a spectrum to improve system throughput/area in high density scenarios of AP (Access Point) and/or STA (Station) with respect to the IEEE 802.11 standard. Considering improving efficiency.

Wearable devices and small computing devices, such as sensors and mobile devices, are limited by their small battery capacity, but they do not support wireless communication technologies such as Wi-Fi, Bluetooth®, and Bluetooth® Low Energy (BLE). Support, connect to and exchange data with other computing devices such as smartphones, tablets and computers. Since these communications consume power, it is important to minimize the energy consumption of these communications in these devices. One ideal strategy for minimizing energy consumption is to power down the communication blocks as frequently as possible while maintaining data transmission and reception without increasing the delay too much. That is, the communication block is transmitted just before data reception and the communication block is turned on only when there is data to wake up, and the power of the communication block is turned off for the rest of the time.

Hereinafter, a low-power wake-up receiver (LP-WUR) will be described.

The communication system (or communication subsystem) described herein includes a main radio (802.11) and a low power wakeup receiver.

The main radio is used to transmit and receive user data. The main radio is turned off if there is no data or packets to send. The low power wake-up receiver wakes up the main radio when there are packets to receive. At this time, user data is transmitted and received by the main radio.

The low power wakeup receiver is not intended for user data. It is simply a receiver to wake the main radio. That is, the transmitter is not included. The low power wake-up receiver is active while the main radio is off. The low power wake-up receiver targets a target power consumption of less than 1 mW in the activated state. In addition, low-power wake-up receivers use a narrow bandwidth of less than 5 MHz. In addition, the target transmission range of the low power wake-up receiver (target transmission range) is the same as the target transmission range of the existing 802.11.

4 is a view showing a low-power wake-up receiver in an environment in which no data is received. 5 is a view showing a low-power wake-up receiver in an environment in which data is received.

4 and 5, when there is data to be transmitted and received, one method of implementing an ideal transmission/reception strategy is a main radio such as Wi-Fi, Bluetooth® radio, and Bluetooth® Radio (BLE). It is to add a low-power wake-up receiver (LP-WUR) that can wake up.

4, the Wi-Fi / BT / BLE 420 is turned off, and the low-power wake-up receiver 430 is turned on without receiving data. According to some studies, the power consumption of such a low power wake-up receiver (LP-WUR) may be less than 1 mW.

However, as shown in FIG. 5, when a wake-up packet is received, the low-power wake-up receiver 530 allows the entire Wi-Fi / BT / BLE radio 520 so that data packets following the wake-up packet can be accurately received. ). However, in some cases, actual data or IEEE 802.11 MAC frames may be included in the wake-up packet. In this case, it is not necessary to wake the entire Wi-Fi / BT / BLE radio 520, but only a part of the Wi-Fi / BT / BLE radio 520 needs to be awakened to perform the necessary process. This can result in significant power savings.

One exemplary technique disclosed herein defines a method for a granular wake-up mode for Wi-Fi/BT/BLE using a low-power wake-up receiver. For example, the actual data contained in the wake-up packet can be transferred directly to the device's memory block without waking up the Wi-Fi / BT / BLE radio.

As another example, if the IEEE 802.11 MAC frame is included in the wakeup packet, only the MAC processor of the Wi-Fi / BT / BLE wireless device needs to be awakened to process the IEEE 802.11 MAC frame included in the wakeup. That is, the PHY module of the Wi-Fi / BT / BLE radio can be turned off or kept in a low power mode.

A number of subdivided wake-up modes are defined for Wi-Fi/BT/BLE radios that use low-power wake-up receivers, so the Wi-Fi/BT/BLE radio must be powered on when a wake-up packet is received. However, according to the above embodiment, only necessary parts (or components) of the Wi-Fi / BT / BLE radio are selectively awakened to save energy and reduce waiting time. Many solutions using low-power wake-up receivers to wake-up the entire Wi-Fi / BT / BLE radio when receiving wake-up packets. One exemplary aspect discussed herein wakes up only the required portion of the Wi-Fi / BT / BLE radio needed to process the received data, thus saving a significant amount of energy and reducing unnecessary latency in waking the main radio. Can.

In addition, in the above embodiment, the low-power wake-up receiver 530 may wake up the main radio 520 based on the wake-up packet transmitted from the transmitter 500.

Also, the transmitting device 500 may be set to transmit a wake-up packet to the receiving device 510. For example, the low-power wake-up receiver 530 may be instructed so that the main radio 520 wakes up.

6 shows an example of a wakeup packet structure according to the present embodiment.

The wakeup packet may include one or more legacy preambles. One or more legacy devices may decode or process the legacy preamble.

In addition, the wakeup packet may include a payload after the legacy preamble. The payload can be modulated by a simple modulation scheme, for example, an On-Off Keying (OOK) modulation scheme.

Referring to FIG. 6, the transmitting device may be configured to generate and/or transmit the wakeup packet 600. The receiving device may be configured to process the received wakeup packet 600.

Further, the wake-up packet 600 may include a legacy preamble or any other preamble 610 defined by the IEEE 802.11 specification. Also, the wake-up packet 600 may include a payload 620.

The legacy preamble provides coexistence with legacy STAs. The legacy preamble 610 for coexistence uses an L-SIG field to protect the packet. Through the L-STF field in the legacy preamble 610, the 802.11 STA can detect the start of a packet. Through the L-SIG field in the legacy preamble 610, the 802.11 STA can know the end of the packet. In addition, a false alarm of the 802.11n terminal can be reduced by adding one symbol modulated with BPSK after the L-SIG. One symbol (4us) modulated with BPSK also has a bandwidth of 20 MHz as in the legacy part. The legacy preamble 610 is a field for a third party legacy STA (STA not including LP-WUR). The legacy preamble 610 is not decoded from LP-WUR.

The payload 620 may include a wake-up preamble 622. The wake-up preamble 622 may include a sequence of bits configured to identify the wake-up packet 600. The wake-up preamble 622 may include a PN sequence, for example.

Also, the payload 620 may include a MAC header 624 including address information of a receiving device receiving the wake-up packet 600 or an identifier of the receiving device.

In addition, the payload 620 may include a frame body 626 that may include other information of the wakeup packet. For example, the frame body 626 may include length or size information of a payload.

Also, the payload 620 may include a Frame Check Sequence (FCS) field 628 including a Cyclic Redundancy Check (CRC) value. For example, the MAC header 624 and the frame body 626 may include a CRC-8 value or a CRC-16 value.

7 shows a signal waveform of a wake-up packet according to the present embodiment.

Referring to FIG. 7, the wake-up packet 700 includes a legacy preamble (802.11 preamble, 710) and a payload modulated by OOK. That is, the legacy preamble and the new LP-WUR signal waveform coexist.

In addition, the legacy preamble 710 may be modulated according to the OFDM modulation scheme. That is, the OOK method is not applied to the legacy preamble 710. On the other hand, the payload can be modulated according to the OOK method. However, the wake-up preamble 722 in the payload may be modulated according to another modulation scheme.

Assuming that the legacy preamble 710 is transmitted on a channel bandwidth of 20 MHz to which 64 FFT is applied, the payload can be transmitted on a channel bandwidth of about 4.06 MHz. This will be described in the OOK pulse design method described later.

First, the modulation technique using the OOK method and the Manchester coding technique will be described.

FIG. 8 is a diagram for explaining a principle in which power consumption is determined according to a ratio of 1 to 0 of bit values constituting binary sequence information using an OOK method.

Referring to FIG. 8, binary sequence information having 1 or 0 as a bit value is represented. If a bit value of 1 or 0 in the binary sequence information is used, OOK modulation type communication can be performed. That is, it is possible to perform OOK modulation type communication by considering bit values of binary sequence information. For example, when a light-emitting diode is used for visible light communication, by turning on the light-emitting diode when the bit value constituting binary sequence information is 1, and turning off the light-emitting diode when the bit value is 0. It is possible to make the light emitting diode blink. The data transmitted in the form of visible light is received and restored by the receiving device according to the flashing of the light emitting diode, thereby enabling communication using visible light. However, since the human eye cannot recognize the flashing of such a light emitting diode, the person feels that the lighting continues to be maintained.

For convenience of description, as shown in FIG. 8, binary sequence information having 10 bit values is used. Referring to FIG. 8, there is binary sequence information having a value of '1001101011'. As described above, when the bit value is 1, the transmitter is turned on, and when the bit value is 0, the transmitter is turned off, the symbol is turned on at 6 bit values out of 10 bit values. ) do. Accordingly, when the symbols are turned on in all 10 bit values, it is said that power consumption is 100%, and according to the duty cycle of FIG. 8, power consumption is 60%.

That is, it can be said that power consumption of the transmitter is determined according to a ratio of 1 and 0 constituting binary sequence information. In other words, if there is a constraint that the power consumption of the transmitter must be maintained at a specific value, the ratio of 1 to 0 constituting binary sequence information should also be maintained. For example, in the case of a lighting device, since the lighting should be maintained at a specific luminance value desired by people, the ratio of 1 to 0 constituting binary sequence information must also be maintained.

However, for the wake-up receiver (WUR), since the receiving device is the subject, transmission power is not critical. The main reason for using OOK is that it consumes very little power when decoding the received signal. There is no significant difference in power consumption in the main radio or WUR until decoding is performed, but a large difference occurs as the decoding process proceeds. Below is the approximate power consumption.

-Existing Wi-Fi power consumption is about 100mW. Specifically, power consumption of Resonator + Oscillator + PLL (1500uW) -> LPF (300uW) -> ADC (63uW) -> decoding processing (OFDM receiver) (100mW) may occur.

-However, WUR power consumption is about 1mW. Specifically, power consumption of Resonator + Oscillator (600uW) -> LPF (300uW) -> ADC(20uW) -> decoding processing (Envelope detector) (1uW) may occur.

9 shows a method of designing an OOK pulse according to the present embodiment.

The OFDM transmission device of 802.11 can be reused to generate the OOK pulse. The transmitting apparatus can generate a sequence having 64 bits by applying a 64-point IFFT like the existing 802.11.

The transmitting device must generate the payload of the wake-up packet by modulating the OOK method. However, since the wake-up packet is for low-power communication, the OOK method is applied to the ON-signal. The on signal is a signal having a real power value, and the off signal (OFF-signal) corresponds to a signal that does not have a real power value. The off-signal also applies the OOK method, but the signal is not generated using the transmission device, and is not considered in the configuration of the wake-up packet since there is no actual transmitted signal.

In the OOK method, information (bit) 1 may be an on signal, and information (bit) 0 may be an off signal. Alternatively, when the Manchester coding scheme is applied, information 1 may indicate a transition from an off signal to an on signal, and information 0 may indicate a transition from an on signal to an off signal. Or, conversely, information 1 may indicate a transition from an on signal to an off signal, and information 0 may indicate a transition from an off signal to an on signal. The Manchester coding scheme will be described later.

Referring to FIG. 9, as shown in the right frequency domain graph 920, the transmitter selects 13 consecutive subcarriers of the 20 MHz band as a sample and applies a sequence. In FIG. 9, among the subcarriers in the 20 MHz band, 13 subcarriers located in the middle are selected as samples. That is, a subcarrier having a subcarrier index of -6 to +6 is selected from among 64 subcarriers. At this time, the subcarrier index 0 may be nulled as 0 as the DC subcarrier. A specific sequence is set only for the 13 subcarriers selected as samples, and all subcarriers excluding the 13 subcarriers (subcarrier indexes -32 to -7 and subcarrier indexes +7 to +31) are all set to 0. .

In addition, since the subcarrier spacing is 312.5 KHz, 13 subcarriers have a channel bandwidth of about 4.06 MHz. That is, it can be considered that there is power only for 4.06 MHz of the 20 MHz band in the frequency domain. By driving the power in this way, the signal-to-noise ratio (SNR) can be increased and power consumption can be reduced in the AC/DC converter of the receiving device. In addition, since the sampling frequency band is reduced to 4.06 MHz, power consumption may be reduced.

In addition, as shown in the left time domain graph 910 of FIG. 9, the transmitting device may generate a single on-signal in the time domain by performing 64-point IFFT on 13 subcarriers. One on signal has a size of 1 bit. That is, a sequence composed of 13 subcarriers may correspond to 1 bit. On the other hand, the transmitting device may not transmit the off signal at all. If IFFT is performed, a symbol of 3.2us can be generated, and if CP (Cyclic Prefix, 0.8us) is included, one symbol having a length of 4us can be generated. That is, one bit indicating one on signal can be carried on one symbol.

The reason why bits are configured and sent as in the above-described embodiment is to reduce power consumption by using an envelope detector in the receiving device. In this way, the receiving device can decode the packet with minimum power.

However, the basic data rate for one piece of information may be 125 Kbps (8us) or 62.5 Kbps (16us).

Signals transmitted in the frequency domain by generalizing the above are as follows. That is, in the 20 MHz band, each signal having a length of K may be transmitted on consecutive K subcarriers out of a total of 64 subcarriers. That is, K is the number of subcarriers used to transmit a signal and can correspond to the bandwidth of the OOK pulse. All coefficients of subcarriers other than K are zero. At this time, the indexes of the K subcarriers used by the signals corresponding to the information 0 and the information 1 are the same. For example, the subcarrier index used may be represented by 33-floor(K/2): 33+ceil(K/2)-1.

At this time, information 1 and information 0 may have the following values.

-Information 0 = zeros(1,K)

-Information 1 = alpha*ones(1,K)

The alpha is a power normalization factor, and may be, for example, 1/sqrt(K).

The slash (/) or comma (comma) used in this specification may mean “and/or” (and/or). For example, “” means “and/or B”, and thus can mean “only A” or “only B” or “one of B”. In addition, technical features that are individually described in one drawing may be individually or simultaneously implemented.

Also, parentheses used in the present specification may mean “for example”. Specifically, when indicated as “control information (EHT-Signal)”, “” may be proposed as an example of “control information”. In addition, even when displayed as “control information (ie, EHT-signal)”, “” may be proposed as an example of “control information”.

The following example of the present specification can be applied to various wireless communication systems. For example, the following example of the present specification may be applied to a wireless local area network (WLAN) system. For example, this specification may be applied to the IEEE 802.11a/g/n/ac standard, or the IEEE 802.11ax standard. In addition, the present specification can be applied to the newly proposed EHT standard or IEEE 802.11be standard. Also, an example of the present specification may be applied to a new wireless LAN standard that improves the EHT standard or IEEE 802.11be.

Hereinafter, to describe the technical features of the present specification, the technical features of the wireless LAN system to which the present specification can be applied will be described.

10 shows an example of a transmitting device and/or a receiving device of the present specification.

The example of FIG. 10 can perform various technical features described below. 10 includes two stations (STA). STA (110, 120) is a mobile terminal (mobile terminal), a wireless device (wireless device), a wireless transmit/receive unit (WTRU), user equipment (User Equipment; UE), mobile station (Mobile Station; MS) , It can also be called various names such as a mobile subscriber unit or simply a user. Further, the STAs 110 and 120 may be called various names such as a receiving device, a transmitting device, a receiving STA, a transmitting STA, a receiving device, and a transmitting device.

The STAs 110 and 120 may perform an access point (AP) role or a non-AP role. That is, the STAs 110 and 120 of the present specification may perform functions of an AP and/or a non-AP.

The STAs 110 and 120 of the present specification may support various communication standards other than the IEEE 802.11 standard. For example, it may support a communication standard (eg, LTE, LTE-A, 5G NR standard) according to the 3GPP standard. Also, the STA of the present specification may be implemented with various devices such as a mobile phone, a vehicle, and a personal computer.

In this specification, the STAs 110 and 120 may include a medium access control (MAC) compliant with the IEEE 802.11 standard and a physical layer interface to a wireless medium.

The first STA 110 may include a processor 111, a memory 112, and a transceiver 113. The illustrated processor, memory, and transceiver may each be implemented as separate chips, or at least two or more blocks/functions may be implemented through one chip.

The transceiver 113 of the first STA performs a signal transmission/reception operation. Specifically, an IEEE 802.11 packet (eg, IEEE 802.11a/b/g/n/ac/ax/be, etc.) can be transmitted and received.

For example, the first STA 110 may perform an intended operation of the AP. For example, the processor 111 of the AP may receive a signal through the transceiver 113, process the received signal, generate a transmission signal, and perform control for signal transmission. The memory 112 of the AP may store a signal (ie, a received signal) received through the transceiver 113 and may store a signal (ie, a transmitted signal) to be transmitted through the transceiver.

For example, the second STA 120 may perform an intended operation of the Non-AP STA. For example, the non-AP transceiver 123 performs a signal transmission/reception operation. Specifically, an IEEE 802.11 packet (eg, IEEE 802.11a/b/g/n/ac/ax/be, etc.) can be transmitted and received.

For example, the processor 121 of the Non-AP STA may receive a signal through the transceiver 123, process the received signal, generate a transmission signal, and perform control for signal transmission. The memory 122 of the Non-AP STA may store a signal (ie, a received signal) received through the transceiver 123 and may store a signal (ie, a transmitted signal) to be transmitted through the transceiver.

For example, the operation of the device indicated as the AP in the following specification may be performed in the first STA 110. Specifically, the operation of the device indicated by the AP is controlled by the processor 111 of the first STA 110, and a related signal is transmitted or received through the transceiver 113 controlled by the processor 111 of the first STA 110. Can be. In addition, control information related to the operation of the AP or the transmission/reception signal of the AP may be stored in the memory 112 of the first STA 110.

For example, the operation of the device indicated as non-AP (or User-STA) in the following specification may be performed in the second STA 120. Specifically, the operation of the device indicated as non-AP is controlled by the processor 121 of the second STA 120, and a related signal is transmitted through the transceiver 123 controlled by the processor 121 of the second STA 120. Or it can be received. In addition, control information related to the operation of the non-AP or an AP transmission/reception signal may be stored in the memory 212 of the second STA 120.

11 is a diagram for explaining a general link setup process.

In step S1110, the STA may perform a network discovery operation. The network discovery operation may include a scanning operation of the STA. That is, in order for the STA to access the network, it is necessary to find a network that can participate. The STA must identify a compatible network before joining a wireless network, and the network identification process existing in a specific area is called scanning. There are two types of scanning methods: active scanning and passive scanning.

11 exemplarily shows a network discovery operation including an active scanning process. In active scanning, the STA performing scanning transmits a probe request frame and waits for a response to discover the AP in the vicinity while moving channels. The responder transmits a probe response frame to the STA that has transmitted the probe request frame in response to the probe request frame. Here, the responder may be the STA that last transmitted a beacon frame from the BSS of the channel being scanned. In the BSS, since the AP transmits the beacon frame, the AP becomes a responder, and in the IBSS, the STAs in the IBSS rotate and transmit the beacon frame, so the responder is not constant. For example, an STA that transmits a probe request frame on channel 1 and receives a probe response frame on channel 1 stores BSS-related information included in the received probe response frame and stores the next channel (for example, number 2). Channel) to perform scanning (ie, probe request/response transmission/reception on channel 2) in the same way.

Although not shown in the example of FIG. 11, the scanning operation may be performed by a passive scanning method. An STA performing scanning based on passive scanning may wait for a beacon frame while moving channels. The beacon frame is one of management frames in IEEE 802.11, and is periodically transmitted to inform the presence of the wireless network and allow STAs performing scanning to find the wireless network and participate in the wireless network. In the BSS, the AP plays a role of periodically transmitting a beacon frame, and in the IBSS, STAs in the IBSS rotate and transmit a beacon frame. Upon receiving the beacon frame, the STA performing scanning stores information on the BSS included in the beacon frame and records beacon frame information in each channel while moving to another channel. The STA receiving the beacon frame may store BSS-related information included in the received beacon frame and move to the next channel to perform scanning in the next channel in the same manner.

The STA discovering the network may perform an authentication process through step S1120. This authentication process may be referred to as a first authentication process (first authentication) to clearly distinguish the security setup operation of step S1140, which will be described later. The authentication process of S1120 may include a process in which the STA transmits an authentication request frame to the AP, and in response, the AP sends an authentication response frame to the STA. The authentication frame used for authentication request/response corresponds to a management frame.

The authentication frame includes authentication algorithm number, authentication transaction sequence number, status code, challenge text, robust security network (RSN), and finite cycle group (Finite Cyclic). Group).

The STA may transmit an authentication request frame to the AP. The AP may determine whether to allow authentication for the corresponding STA based on the information included in the received authentication request frame. The AP may provide the result of the authentication process to the STA through the authentication response frame.

The successfully authenticated STA may perform a connection process based on step S1130. The connection process includes a process in which the STA transmits an association request frame to the AP, and in response, the AP sends an association response frame to the STA. For example, the connection request frame includes information related to various capabilities, beacon listening interval, service set identifier (SSID), supported rates, supported channels, RSN, and mobility domain. , Supported operating classes, TIM broadcast request, and information on interworking service capabilities. For example, the connection response frame includes information related to various capabilities, status codes, association ID (AID), support rate, enhanced distributed channel access (EDCA) parameter set, received channel power indicator (RCPI), and received signal to noise (RSNI) Indicator), mobility domain, timeout interval (association comeback time (association comeback time)), overlapping (overlapping) BSS scan parameters, TIM broadcast response, QoS map, and other information.

Thereafter, in step S1140, the STA may perform a security setup process. The security setup process of step S1140 may include, for example, a process of performing private key setup through 4-way handshaking through an Extensible Authentication Protocol over LAN (EAPOL) frame. .

12 is a diagram showing an example of a PPDU used in the IEEE standard.

As illustrated, various types of PHY protocol data units (PPDUs) have been used in standards such as IEEE a/g/n/ac. Specifically, the LTF and STF fields included a training signal, and SIG-A and SIG-B included control information for the receiving station, and the data field contained user data corresponding to a MAC PDU/Aggregated MAC PDU (PSDU). Was included.

12 also includes an example of the HE PPDU of the IEEE 802.11ax standard. The HE PPDU according to FIG. 12 is an example of a PPDU for multiple users, HE-SIG-B is included only for multiple users, and the corresponding HE-SIG-B may be omitted in the PPDU for a single user.

As shown, HE-PPDU for multiple users (MU) is a legacy-short training field (L-STF), legacy-long training field (L-LTF), legacy-signal (L-SIG), High efficiency-signal A (HE-SIG-A), high efficiency-signal-B (HE-SIG-B), high efficiency-short training field (HE-STF), high efficiency-long training field (HE-LTF) , Data field (or MAC payload) and PE (Packet Extension) field. Each field may be transmitted during the illustrated time period (ie, 4 or 8 ms, etc.).

Hereinafter, a resource unit (RU) used in the PPDU will be described. The resource unit may include a plurality of subcarriers (or tones). The resource unit may be used when transmitting signals to multiple STAs based on the OFDMA technique. Also, when transmitting a signal to one STA, a resource unit may be defined. Resource units can be used for STF, LTF, data fields, and the like.

Hereinafter, a PPDU transmitted/received by the STA of the present specification is described.

13 shows an example of a PPDU used in the present specification.

The PPDU of FIG. 13 may be called various names such as an EHT PPDU, a transmitting PPDU, a receiving PPDU, a first type or an N-type PPDU. In addition, it can be used in a new wireless LAN system with an improved EHT system and/or EHT system.

The sub-field of FIG. 13 may be changed to various names. For example, the SIG A field may be called an EHT-SIG-A field, the SIG B field an EHT-SIG-B, the STF field an EHT-STF field, and the LTF field an EHT-LTF field.

The subcarrier spacing of the L-LTF, L-STF, L-SIG, and RL-SIG fields of FIG. 13 may be determined as 312.5 kHz, and the subcarrier spacing of the STF, LTF, and Data fields may be determined as 78.125 kHz. That is, the subcarrier index of the L-LTF, L-STF, L-SIG, and RL-SIG fields may be displayed in 312.5 kHz units, and the subcarrier index of the STF, LTF, and Data fields may be displayed in 78.125 kHz units.

The SIG A and/or SIG B fields of FIG. 13 may include additional fields (eg, SIG C or one control symbol, etc.). All/part of the SIG A and SIG B fields may have a subcarrier spacing of 312.5 kHz, and the remaining subcarrier spacing of 78.125 kHz.

The PPDU of FIG. 13 may have the same L-LTF and L-STF fields.

The L-SIG field of FIG. 13 may include, for example, 24-bit bit information. For example, the 24-bit information may include a rate field of 4 bits, a reserved bit of 1 bit, a length field of 12 bits, a parity bit of 1 bit, and a tail bit of 6 bits. For example, the 12-bit Length field may include information on the number of octets of the PSDU (Physical Service Data Unit). For example, the value of the 12-bit Length field may be determined based on the type of PPDU. For example, if the PPDU is a non-HT, HT, VHT PPDU or EHT PPDU, the value of the Length field may be determined in multiples of 3. For example, when the PPDU is an HE PPDU, the value of the Length field may be determined as “multiple of 3 + 1” or “multiple of 3 +2”. In other words, the value of the Length field can be determined as a multiple of 3 for a non-HT, HT, VHT PPDU, or an EHT PPDU, and the value of the Length field for a HE PPDU is a multiple of 3 + 1 or a multiple of 3 +2”.

For example, the transmitting STA may apply BCC encoding based on a code rate of 1/2 to the 24-bit information of the L-SIG field. Thereafter, the transmitting STA may acquire 48 bits of BCC coded bits. For the 48-bit coded bit, BPSK modulation may be applied to generate 48 BPSK symbols. The transmitting STA can map 48 BPSK symbols to positions other than the pilot subcarrier {subcarrier index -21, -7, +7, +21} and DC subcarrier {subcarrier index 0}. As a result, 48 BPSK symbols can be mapped to subcarrier indexes -26 to -22, -20 to -8, -6 to -1, +1 to +6, +8 to +20, and +22 to +26. have. The transmitting STA may further map the signals of {-1, -1, -1, 1} to the subcarrier index {-28, -27, +27, 28}. The above signal can be used for channel estimation for a frequency domain corresponding to {-28, -27, +27, 28}.

The transmitting STA may generate the RL-SIG generated in the same way as the L-SIG. BPSK modulation is applied to RL-SIG. The receiving STA can know that the receiving PPDU is an HE PPDU or an EHT PPDU based on the existence of the RL-SIG.

After RL-SIG of FIG. 13, for example, EHT-SIG-A or one control symbol may be inserted. The symbol (i.e., EHT-SIG-A or one control symbol) contiguous to RL-SIG may include 26 bits of information, and may include information for identifying the type of EHT PPDU. For example, if the EHT PPDU is divided into various types (e.g., EHT PPDU supporting SU, EHT PPDU supporting MU, EHT PPDU related to Trigger Frame, EHT PPDU related to Extended Range transmission, etc.) , EHT PPDU type information may be included in a symbol subsequent to the RL-SIG.

The symbol subsequent to the RL-SIG may include, for example, information about the length of the TXOP and information about the BSS color ID. For example, a SIG-A field may be configured in succession to a symbol (eg, one control symbol) consecutive to RL-SIG. Alternatively, a symbol subsequent to RL-SIG may be a SIG-A field.

For example, the SIG-A field is 1) a DL/UL indicator, 2) a BSS color field that is an identifier of a BSS, 3) a field including information on the remaining time of the current TXOP section, 4) a bandwidth. Bandwidth field including information, 5) Field including information on MCS technique applied to SIG-B, 6) Contains information related to whether dual subcarrier modulation technique is applied to SIG-B Indication field, 7) a field including information on the number of symbols used for SIG-B, 8) a field including information on whether SIG-B is generated over the entire band, 9) LTF/STF Field including information on the type of 10, and information on a field indicating the length of the LTF and the length of the CP.

The STF of FIG. 13 may be used to improve automatic gain control estimation in a multiple input multiple output (MIMO) environment or OFDMA environment. The LTF of FIG. 13 may be used to estimate a channel in a MIMO environment or OFDMA environment.

The STF of FIG. 13 can be set to various types. For example, a first type of STF (ie, 1x STF) may be generated based on a first type STF sequence in which non-zero coefficients are arranged at 16 subcarrier intervals. The STF signal generated based on the first type STF sequence may have a period of 0.8 μs, and the period signal of 0.8 μs may be repeated 5 times to become a first type STF having a length of 4 μs. For example, a second type (that is, 2x STF) among STFs may be generated based on a second type STF sequence in which non-zero coefficients are arranged at 8 subcarrier intervals. The STF signal generated based on the second type STF sequence may have a period of 1.6 μs, and the period signal of 1.6 μs may be repeated 5 times to become a second type EHT-STF having a length of 8 μs. For example, a third type (ie, 4x EHT-STF) among STFs may be generated based on a third type STF sequence in which non-zero coefficients are arranged at four subcarrier intervals. The STF signal generated based on the third type STF sequence may have a period of 3.2 μs, and the period signal of 3.2 μs may be repeated 5 times to become a third type EHT-STF having a length of 16 μs. Only some of the above-described first to third types of EHT-STF sequences may be used. In addition, the EHT-LTF field may have first, second, and third types (ie, 1x, 2x, 4x LTF). For example, the first/second/third type LTF field may be generated based on an LTF sequence in which non-zero coefficients are arranged at 4/2/1 subcarrier intervals. The first/second/third type LTF may have a time length of 3.2/6.4/12.8 μs. In addition, various lengths of GI (eg, 0.8/1/6/3.2 μs) may be applied to the first/second/third type LTF.

Information about the type of STF and/or LTF (including information on GI applied to LTF) may be included in the SIG A field and/or the SIG B field of FIG. 12.

The PPDU of FIG. 13 may be identified as an EHT PPDU based on the following method.

The receiving STA may determine the type of the received PPDU as the EHT PPDU based on the following. For example, 1) the first symbol after the L-LTF signal of the received PPDU is BPSK, 2) the RL-SIG where the L-SIG of the received PPDU is repeated is detected, and 3) the length of the L-SIG of the received PPDU. When the result of applying "modulo 3" to the value is detected as "0", the received PPDU may be determined as the EHT PPDU. When the received PPDU is determined to be the EHT PPDU, the receiving STA is after RL-SIG in FIG. The type of the EHT PPDU (eg, SU/MU/Trigger-based/Extended Range type) may be detected based on the bit information included in the symbol of .. In other words, the receiving STA is 1) L- which is the BSPK. First symbol after the LTF signal, 2) L-SIG field, L-SIG that is the same as L-SIG, and 3) L-SIG including a Length field where the result of applying “modulo 3” is set to “0” Based on the SIG, the received PPDU can be determined as an EHT PPDU.

For example, the receiving STA may determine the type of the received PPDU as HE PPDU based on the following. For example, 1) the first symbol after the L-LTF signal is BPSK, 2) the RL-SIG where the L-SIG is repeated is detected, and 3) “modulo 3” is applied to the length value of the L-SIG. When the result is detected as “1” or “2”, the received PPDU may be determined as the HE PPDU.

For example, the receiving STA may determine the type of the received PPDU as non-HT, HT and VHT PPDU based on the following. For example, 1) the first symbol after the L-LTF signal is BPSK, 2) the RL-SIG in which the L-SIG is repeated is not detected, and 3) the receiving STA determines that it is not 802.11ax, and transmits the legacy STA. It operates as a state machine to determine, and determines the constellation of two symbols received after the L-SIG. Accordingly, the received PPDU may be determined as non-HT, HT and VHT PPDU.

1.Multi BSSID (Multiple BSSID )

Using the multiple BSSID function, information on the BSSID can be advertised using a single beacon or probe response frame instead of multiple beacon and probe response frames each corresponding to a single BSSID. The multiple BSSID function may display a buffered frame for multiple BSSIDs using a single traffic indication map (TIM) element in a single beacon.

Multiple BSSID sets may be defined as follows.

All members of the multiple BSSID set use a common operating class, channel, channel access functions and antenna connector.

Multiple BSSID sets have 2 ⁿ maximum ranges for at least one n.

All BSSIDs in a multi-BSSID set are allocated in a manner that cannot be used as a MAC address of an STA using a different operating class, channel, or antenna connector.

For example, if an AP within a BSS with BSSIDs 16, 17, and 27 shares an operating class, channel, and antenna connector, and the MAC address range including 16-31 is not assigned to another STA using another antenna connector, BSSID 16, 17 and 27 are members of multiple BSSID sets.

Multiple BSSID sets are described as n = 4 (2 ⁿ = 16) with a BSSID in the range 0x00000000001X. For example, since one or more of the BSSIDs in the 0x0000000000XX range can be used as BSSIDs by APs that do not share the same operating class, channel, and antenna connector, multiple BSSID sets n = 8 cannot be described.

Multiple BSSID elements with or without optional subelements indicate that all APs and PCPs within the indicated BSSID range are transmitted using a common operating class, channel and antenna connector.

14 shows an example of the format of multiple BSSID elements.

Referring to FIG. 14, the Max BSSID Indicator field includes a value assigned to n. Here, 2 ⁿ is the maximum number of BSSIDs in a set of multiple BSSIDs including a reference BSSID. The actual number of BSSIDs in the multiple BSSID set is not explicitly signaled.

When multiple BSSID elements are transmitted in a beacon, DMG beacon or probe response frame, the reference BSSID is the BSSID of the frame. At least one or more multiple BSSID elements may be included in a beacon or DMG beacon frame. The AP or DMG STA determines the number of multiple BSSID elements. The AP or DMG STA does not fragment the nontransmitted BSSID profile subelement for a single BSSID in two multiple BSSID elements unless the length of the nontransmitted BSSID profile subelement exceeds 255 octets. When multiple BSSID elements are transmitted from a neighbor report element to a child element, the reference BSSID is the BSSID field of the neighbor report element.

The optional sub-element field has zero or more sub-elements. The sub-element type and the order of sub-elements are defined as follows. The sub-element ID field values of the defined sub-elements are defined in the table below.

The nontransmitted BSSID Profile Subelement includes a list of elements for one or more APs or DMG STAs having a nontransmitted BSSID as follows.

-SSID and multiple BSSID-index subelements are included in the Nontransmitted BSSID Profile subelement.

-If multiple BSSID elements are included in the beacon frame and the TIM field indicates that there is a group addressed frame buffered for the nontransmitted BSSID, the FMS Descriptor element is included in the Nontransmitted BSSID Profile subelement.

Multiple BSSID elements are included in the beacon frame, DMG beacon frame and probe response frame. The use of multiple BSSID elements is described in the Nontransmitted BSSID Advertising Procedure.

15 shows an example of a multiple BSSID-Index element format.

Referring to FIG. 15, the value of the Length field is 1 octet when the Multiple BSSID-Index element is included in the probe response frame, and 3 octets if not included.

The BSSID Index field is a value between 1 and 2 ⁿ -1 that identifies a nontransmitted BSSID, and n is a non-zero positive integer value.

The Multiple BSSID-Index element is included in the nontransmitted BSSID profile element described above. The use of multiple BSSID elements and frames has been previously described.

2. WUR MAC frame format for (Wake-up Radio) frames

16 shows an example of the WUR frame format.

Referring to FIG. 16, the WUR frame includes MAC header, frame body, and FCS fields.

The MAC header includes Frame Control, ID, and Type Dependent Control fields. The Frame Body field is variable in length and is selectively present according to a specific WUR frame type. A WUR frame without a Frame Body field is called a FL (Fixed-length) WUR frame. A WUR frame with a Frame Body field is called a variable-length (VL) WUR frame. The FCS field includes one of 16-bit CRC or 16-bit MIC based on the Protected subfield included in the Frame Control field described later.

The ID field of FIG. 16 includes an identifier for a WUR frame of the type selected in the table below. The type of identifier is based on the type of WUR frame.

17 shows an example of a Frame Control field format.

Referring to FIG. 17, the Type subfield indicates the type of WUR frame. Type subfields can be defined as shown in the table below.

Referring to FIG. 17, the Length Present subfield indicates whether the Length/Miscellaneous subfield includes the Length subfield. The Length/Miscellaneous subfield includes the Length subfield when the Length Present subfield is 1, and the Miscellaneous subfield when the Length Present subfield is not 1. The Length subfield indicates the length of the Frame Body field.

The ID field of the WUR beacon frame is set to the transmitter ID. In the WUR beacon frame, there is no Frame Body field.

The ID field of the FL WUR wake-up frame includes one of the following.

-WUR ID when a frame is individually addressed as a WUR non-AP STA

-WUR Group ID if the frame is grouped into all WUR non-AP STAs belonging to the group identified by WUR Group ID

-If the frame is a broadcast addressed frame transmitted by the WUR AP identified by the transmitter ID, the transmitter ID

-Nontransmitter ID when the frame is a broadcast addressed frame transmitted by the WUR AP identified as a nontransmitted ID when dot11MultiBSSIDImplemented is true

The ID field of the VL WUR wake-up frame includes the WUR Group ID, and the frame is a group identified by the WUR ID included in the Frame Body field and addressed by one or more WUR non-AP STAs belonging to the group identified by the WUR Group ID. .

18 shows an example of a Type Dependent Control field format.

Referring to FIG. 18, the Type Dependent Control field of the WUR wake-up frame includes a Sequence Number subfield and a Counter subfield.

The Counter subfield includes a BSS Update Counter field when a WUR wakeup frame is broadcast. The BSS Update Counter field is defined as an unsigned integer initialized to 0, and is incremented when an important update to the BSS parameter occurs.

Alternatively, the Counter subfield includes PN1 [0:3] when the WUR wakeup frame is not broadcast. The Protected subfield of the Frame Control field is 1, and the most recently transmitted WUR Operation element has a common PN subfield equal to 0.

19 shows an example of a miscellaneous subfield format.

If the Length Present subfield is 0, a Miscellaneous subfield exists. The format of the miscellaneous subfield may be represented as shown in FIG. 19 when the frame is a broadcast or group addressed FL WUR wakeup frame. Miscellaneous subfields are reserved for FL WUR wakeup frames that are not broadcast addressed or group addressed.

WUR wakeup frames addressed as broadcasts are always FL WUR wakeup frames.

Referring to FIG. 19, the Group Addressed BU subfield is set to 1 to indicate that one or more group addressed frames are buffered in the AP corresponding to the BSSID displayed in the ID field. Otherwise, the Group Addressed BU subfield is set to 0. The Group Addressed BU subfield is reserved in the group addressed FL WUR wakeup frame.

Hereinafter, a method of setting the identifier of the WUR frame will be described.

The ID field of the WUR frame includes an identifier (ID) selected in the space of the identifier, and is composed of all integer values between 0 and 4095.

The WUR AP must ensure that each identifier is part of a Transmitter ID, WUR Group ID, WUR ID, Nontransmitter ID or OUI.

The WUR AP can provide a certain level of security and personal information by sporadically changing the identifier used in the WUR BSS.

The WUR non-AP STA maintains a plurality of ID lists and can process WUR frames including these IDs.

The list of IDs maintained by the WUR non-AP STA includes:

-WUR ID of individually addressed FL WUR wake-up frames.

-WUR beacon, WUR discovery frame and transmitter ID of the broadcast addressed WUR wakeup frame transmitted by the AP corresponding to the transmitted BSSID.

-nontransmitter ID of the WUR wakeup frame transmitted and broadcast addressed by the AP corresponding to the nontransmitted BSSID

The WUR STA uses compressed BSSIDs to obtain several identifiers defined below.

The compressed BSSID is the same as the 32-bit CRC calculated through the BSSID included in the beacon frame transmitted by the WUR AP when dot11MultiBSSIDImplemented is false, and is calculated through the transmitted BSSID of the multiple BSSID set when dot11MultiBSSIDImplemented is true.

<Transmitter ID>

The transmitter ID identifies the WUR AP transmitting the WUR frame.

The WUR wakeup frame is a broadcast addressed WUR wakeup frame when the WUR wakeup frame has a transmitter ID in the ID field.

If dot11MultiBSSIDImplemented is false, the WUR wake-up frame is sent to all WUR non-AP STAs associated with the WUR AP, or if dot11MultiBSSIDImplemented true, it is sent to all WUR non-AP STAs associated with the AP corresponding to the transmitted BSSID.

The WUR beacon frame and WUR discovery frame transmitted by the WUR AP must have a transmitter ID in the ID field.

A WUR non-AP STA associated with a nontransmitted BSSID is identified with a nontransmitter ID. These WUR non-AP STAs associated with APs corresponding to nontransmitted BSSIDs in multiple BSSID sets are expected to receive WUR beacons and WUR discovery frames transmitted with transmitter IDs in the ID field, and frames transmitted with transmitter IDs in the ID field. It is not expected to receive other types of WUR frames.

The WUR AP should be used as the transmitter ID of the WUR frame transmitting 12 LSBs of the compressed BSSID.

<WUR Group ID>

The WUR Group ID identifies one or more WUR non-AP STA groups and is selected from the WUR Group ID space, which is a subset of consecutive values obtained in the identifier space. The FL WUR wakeup frame with the WUR Group ID in the ID field is defined as a group addressed WUR frame addressed to all WUR non-AP STAs identified by the WUR Group ID. VL WUR wakeup frame with WUR Group ID in ID field is identified by WUR ID included in Frame Body field, included in Frame Body field, and addressed to all WUR non-AP STAs belonging to the group identified by WUR Group ID Group addressed WUR frame.

<WUR ID>

The WUR ID identifies a WUR non-AP STA that is an intended recipient of the WUR frame. A WUR frame with a WUR ID in the ID field is defined as an individually addressed WUR frame addressed to the WUR non-AP STA identified by the WUR ID.

<Nontransmitter ID>

The nontransmitter ID identifies a nontransmitted BSSID in a set of multiple BSSIDs.

The WUR wakeup frame is a WUR wakeup frame addressed as a broadcast when the WUR wakeup frame has a nontransmitter ID in the ID field. The WUR wakeup frame is sent to all WUR non-AP STAs associated with an AP corresponding to a nontransmitted BSSID in a plurality of BSSID sets.

A WUR AP operating a multi-BSSID set that includes a nontransmitted BSSID and a WUR non-AP STA that is a member of the BSS corresponding to the nontransmitted BSSID must calculate the nontransmitter ID as k + transmitter ID, where k is the corresponding BSS for the nontransmitted BSSID. The same as the BSSID index field corresponding to, and the addition performed between the two identifiers is circular modulo 2 ¹² .

The terms used above are summarized as follows.

Broadcast WUR wake-up frame is a WUR wake-up frame with the same ID field as transmitter ID or nontransmitter ID.

Compressed BSSID is an identifier for WUR BSS obtained by calculating a 32-bit CRC through the BSSID included in the beacon frame transmitted by the WUR AP.

Transmitter IDs are not supported for multiple BSSID operations or addressed to all WUR non-AP STAs associated with multiple BSSID sets of BSSIDs, or for multiple WSS non-APs supported for multiple BSSID operations or to discover or synchronize WUR APs. When addressed to STAs, this is an identifier used in the WUR AP to identify broadcast addressed WUR frames addressed to all WUR non-AP STAs associated with the WUR AP.

The Nontransmitter ID is an identifier used by the WUR AP to identify broadcast WUR frames addressed to all non-AP STAs associated with an AP corresponding to a nontransmitted BSSID among multiple BSSID sets when multi-BSSID operation is supported.

3. Offered Example

This specification relates to a method of transmitting a broadcast wake up frame to a user equipment in a low power WLAN system (802.11ba), and in particular, a method of transmitting a wake up frame in consideration of multiple BSS network environments.

As mentioned above, if the WUR AP has a group addressed frame in the buffer, the group addressed BU field in the broadcast wake up frame is set to 1 and transmitted. At this time, set the ID field of the wake up frame to Transmitter ID (TXID) and transmit. However, it does not take into account APs with multiple BSSIDs. This specification proposes a method for an AP having multiple BSSID sets to transmit a wake up frame.

APs configuring multiple BSSs set have a BSSID for each BSS. The BSS transmitting the Beacon frame is mapped to the Transmitted BSSID (first BSSID), the remaining BSSs are mapped to the Nontransmitted BSSID (second BSSID), and BSSIDs can be calculated according to the rules defined in the existing specification.

Since the transmitter ID defined in the WUR (11ba) specification is calculated based on the BSSID, IDs for each BSS in an AP having multiple BSSs set can be assigned as follows.

1) As the ID (first ID) for the BSS mapped to the Transmitted BSSID, the Transmitter ID calculated based on the Transmitted BSSID is used as the ID for the corresponding BSS.

2) Nontransmitter IDs (second IDs) for BSSs mapped to nontransmitted BSSIDs can be calculated by one of the following methods.

-Option 1: When the value corresponding to the location of the nontransmitted BSSID (second BSSID) in the partial virtual bitmap of the TIM element is set to K, (Transmitter ID + K) MOD 2 ¹² One value becomes the Nontransmitter ID.

-Option 2: If the value of the BSSID-Index field corresponding to the BSS for the nontransmitted BSSID (second BSSID) is set to K, (Transmitter ID + K) MOD 2 ¹² One value becomes the Nontransmitter ID.

AP or STA can calculate the Nontransmitter ID using the above equation.

The AP that maintains the Multiple BSS set displays the ID field of the Wake Up frame when it wants to inform the UEs that it has a Group Addressed BU/frame to UEs belonging to the BSS corresponding to the Transmitted BSSID (first BSSID). Transmit by setting with Transmitter ID. At this time, the group addressed BU field of the wake up frame is set to 1.

When notifying the terminals of having a Group Addressed BU/frame to terminals belonging to the BSS corresponding to the nontransmitted BSSID (second BSSID), the ID field of the Wake Up frame is set to Nontransmitter ID and transmitted. At this time, the group addressed BU field of the wake up frame is set to 1.

In order to inform that the AP with multiple BSSIDs has group addressed BU/frame/data for terminals belonging to a specific BSS, ID (Transmitter ID or Nontransmitter ID) corresponding to the BSS is used as an ID field of the Wake Up frame. In addition, when transmitting to a group addressed BU to all STAs included in all BSSs belonging to the Multiple BSSID set, the AP corresponds to each BSS in the wake up frame for each BSS. (Transmitter ID or Nontransmitter ID) is included to send multiple times.

One way to solve this is that in the ID field of the Wake Up frame, all bits in a specific value (e.g., 0 or 4095 (ID field (12 bits))) indicating that it is for all BSSs that are not Transmitter IDs or Nontransmitter IDs. Set to 1 and will be described with 4095 in this specification.)). For example, if a specific value is 4095, the AP transmits a Wake Up frame by setting the ID field of the Wake Up frame to 4095 when trying to wake up all terminals belonging to all BSSs belonging to it.

As mentioned above, this broadcast wake up frame can be used when notifying the terminal to indicate that the Group Addressed BU has it, or it can be used as a counter field to inform the BSS parameter update as defined in the 802.11ba specification. .

1) If you want to inform all terminals belonging to all BSS belonging to the AP that there is Group Addressed BU to be transmitted, set the Group Addressed BU field to 1 without increasing the Counter field, and set the ID field to 4095 to wake. Send up frame.

2) To inform that all terminals belonging to the AP have all the BSS parameters to be updated, increase the Counter field by 1 and set the ID field to 4095 to transmit the Wake Up frame.

3) If you want to inform all terminals belonging to the AP that there is a Group Addressed BU to be transmitted, and all terminals belonging to all BSS that belong to the AP, there is a BSS parameter to be updated, increase the Counter field by 1 After setting the addressed BU field to 1, set the ID field to 4095 to transmit the Wake Up frame.

As mentioned above, it is natural that a specific value to enter the ID field may be set to a value other than 4095 (for example, 0).

Since neighboring APs use the same value, the UEs cannot know whether the Wake Up frame received with the ID field is sent by the AP belonging to the BSS associated with it. However, since the CRC of the Wake Up frame is calculated using the Embedded BSSID (BSSID calculated based on the BSSID included in the beacon in the 802.11a spec), the UE checks the CRC when receiving the Wake Up frame, and If an AP belonging to an associated BSS is not sent, the Wake Up frame may be discarded and PCR (Primary Connectivity Radio) may not be transferred to the awake state.

The specific value (for example, 0 or 4095) used to indicate all terminals belonging to all BSSs of the AP having the Multiple BSSID set defined above may enter the ID field of the Wake Up frame including Multiple WUR IDs. In the current 802.11ba specification, the ID field of the corresponding Wake Up frame is set to 0. If the ID field of the corresponding Wake Up frame is set to 4095, and the value of the Length field is 0, it indicates broadcast wake up for all terminals associated with all BSSs belonging to the AP, and the ID field is 4095. Set to, and the value of the Length field is greater than 0, indicates a Wake Up frame including multiple WUR IDs.

Instead of using the All BSSs ID used to indicate all the terminals belonging to all BSSs of the AP having the Multiple BSSID set defined above as a specific value (for example, 0 or 4095), it is calculated based on the Transmitter ID. Can. For example, All BSSs ID may be calculated as Transmitter ID-Y (Y is an integer greater than 0). For example, for ease of implementation, Y is preferably 1. (That is, All BSSs ID = Transmitter ID-1 is set.) For example, if Transmitter ID is set to X, All BSSs ID may be X-Y. At this time, if X is 1000 and Y is 1, All BSSs ID is 999. In addition, when the Transmitter ID is set to X, All BSSs ID may be X+Y. At this time, Y may be 0 or 4095. According to the above method, there is no need for the AP to separately inform the terminal of the All BSSs ID.

Although the specific value mentioned above may be determined by the system, the AP may allocate the All BSSs ID to the terminal. When implementing a set of multiple BSSIDs (e.g., dot11MultiBSSIDActivated is true or dot11MultiBSSIDImplemented is true), to indicate all BSSs corresponding to transmitted BSSIDs and non-transmitted BSSIDs, the AP is All BSSs ID (name is changed All BSSs ID may be assigned to the WUR STA by including the field in the PCR/WLAN frame (eg, WUR Action frame, Association response frame). All BSSIDs ID is a common value in all BSSs in the AP, and values used in an identifier space (eg, 0 to 4095) (eg, assigned Group IDs, Transmitter ID, Non -transmitter ID, assigned WUR IDs, etc.) are not assigned as All BSSs ID.

A terminal that receives a WUR frame containing the assigned ID, All BSSs ID, considers that the corresponding WUR frame comes to it.

If the integer value of 12MSBs of the compressed BSSID is 0 or 4095, the transmitter ID of the AP is set to 1.

Alternatively, the Transmitter ID can be defined to point to all BSSs (or APs having BSSs) corresponding to transmitted BSSIDs and non-transmitted BSSIDs. That is, when multiple BSSID sets are implemented (e.g., dot11MultiBSSIDActivated is true or dot11MultiBSSIDImplemented is true), a broadcast WUR frame (e.g., WUR Beacon, broadcast wake up frame, etc.) with an ID set to Transmitter ID is Addressed to all STAs associated with transmitted BSSIDs and BSSs (or APs) corresponding to all non-transmitted BSSIDs.

In this case, since there is no way to indicate the BSS (AP) corresponding to the transmitted BSSID, it must be additionally defined using the following method.

When the AP allocates the WUR parameter through PCR to WUR STAs belonging to (associated with) the BSS (AP) corresponding to the transmitted BSSID, the AP includes a PCR frame including the WUR parameter (eg, WUR Action frame or Association response) In frame, etc.), one ID corresponding to the transmitted BSSID can be additionally assigned. The WUR STA linked to the BSS corresponding to the Transmitted BSSID stores the assigned ID, and when receiving a WUR frame including the assigned ID, processes the frame as an addressed frame. For example, if the corresponding ID is included in the broadcast wake up frame, the terminal checks the fields of the wake up frame (eg, Group Addressed BU field, Counter field) to receive the Group Addressed BU or BSS. After deciding whether to update the parameter, perform the appropriate operation as defined in the specification.

Hereinafter, the above-described embodiment will be described with reference to FIGS. 1 to 19.

20 is a flowchart illustrating a procedure for transmitting a broadcast frame in a transmitting STA according to the present embodiment.

The example of FIG. 20 may be performed in a network environment in which a next generation WLAN system is supported. The next-generation wireless LAN system is an improved wireless LAN system that can satisfy backward compatibility with the 802.11ax system.

The example of FIG. 20 is performed by a transmitting STA, and the transmitting STA may correspond to an Extremely High Throughput (EHT) access point (AP) or a Wake Up Radio (WUR) AP. The receiving STA of FIG. 20 may correspond to an EHT STA or WUR STA.

In step S2010, a transmitting STA (station) having multiple BSSIDs (Multiple Basic Service Set IDentification) generates the broadcast frame. The broadcast frame may be a broadcast wake up frame, and in the embodiments herein, the broadcast frame will be described assuming a broadcast wake up frame unless otherwise specified.

In step S2020, the transmitting STA transmits the broadcast frame to the receiving STA.

The multiple BSSIDs include a first BSSID and a second BSSID.

The first BSSID is an identifier of a first BSS that transmits a beacon frame. The first BSSID may correspond to a Transmitted BSSID.

The second BSSID is an identifier of a second BSS except for the first BSS in all BSSs mapped to the multiple BSSIDs. The second BSSID may correspond to a nontransmitted BSSID.

Conventionally, in order to wake up the receiving STAs belonging to all BSSs mapped to the multiple BSSIDs, the transmitting STA includes each ID (the first BSSID or the second BSSID) corresponding to each of the BSSs in a wake-up frame. There has been a problem in that the WSS frame has to be repeatedly transmitted multiple times for the BSS.

In contrast, this embodiment proposes a method for a transmitting STA having multiple BSSIDs to wake up receiving STAs belonging to all BSSs mapped to multiple BSSIDs at once by transmitting a broadcast frame. The proposed method is as follows.

The broadcast frame includes an ID (IDentification) field.

The ID field is set to IDs for all the BSSs.

IDs for all the BSSs are obtained based on a transmitter ID identifying the transmitting STA.

The transmitter ID is obtained based on the first BSSID.

That is, in order to wake up all receiving STAs belonging to all BSSs of a transmitting STA having multiple BSSIDs, IDs for all the BSSs are set. Specifically, IDs for all the BSSs may be determined by subtracting Y from the transmitter ID. In this case, Y may be an integer greater than 0. As another example, IDs for all the BSSs may be determined by adding Y to the transmitter ID. At this time, the Y may be 0 or 4095.

The receiving STA is a terminal belonging to one of the BSS corresponding to the transmission ID (transmitter ID) or the BSS corresponding to the non-transmitter ID (ID) for all BSS calculated using the method proposed in the present invention When a frame including (all BSSs ID) is received, the corresponding terminal is regarded as a frame transmitted to it.

All terminals belonging to all of the BSS may be woken up based on the broadcast frame (particularly in the case of a broadcast wakeup frame). As a result, PCR (Primary Connectivity Radio) may be transitioned to an awake state in all terminals belonging to all the BSS.

According to the above-described embodiment, by setting the ID field of the broadcast frame to the IDs of all the BSSs, the transmitting STA can efficiently wake up the receiving STAs belonging to all the BSSs at once by transmitting one broadcast frame. It works.

The identifier of the first BSS can be obtained based on the ID of the transmitting end, and the identifier of the second BSS can be obtained based on a non-transmitter ID. The non-transmission end ID is an ID for a virtual transmission STA. A transmitting STA with multiple BSSIDs can make multiple virtual BSSs, and the virtual BSSs are collocated with each other. The receiving STA may determine that there are logically multiple APs according to the virtual BSS based on the multiple BSSIDs.

The non-transmission end ID may be determined by modulo 2 ¹² to the sum of the transmission end ID and K.

The K may be a value of the BSSID index field for the second BSS.

The broadcast frame may include a group addressed buffer field.

The group addressed buffer field may include information on whether a group addressed buffer exists to be transmitted by the transmitting STA to all terminals belonging to the BSS. That is, when there is a group addressed buffer to be transmitted by the transmitting STA to all terminals belonging to all the BSS, the group addressed buffer field may be set to 1.

The broadcast frame may further include a counter field.

The counter field may include information on whether there is a BSS parameter to be updated for all terminals belonging to the BSS. That is, when there is a BSS parameter to be updated for all terminals belonging to all the BSS, the counter field may be set to 1.

As another example, the transmitting STA may include the IDs for all the BSSs in a PCR frame or a WLAN frame (Action frame or Association response frame) and transmit the IDs to the receiving STAs. The receiving STA may check the IDs of all the BSSs, receive the broadcast frame, and decode the group addressed buffer and the counter field.

21 is a flowchart illustrating a procedure for receiving a broadcast frame at a receiving STA according to the present embodiment.

The example of FIG. 21 may be performed in a network environment in which a next generation WLAN system is supported. The next-generation wireless LAN system is an improved wireless LAN system that can satisfy backward compatibility with the 802.11ax system.

The example of FIG. 21 is performed at a receiving STA, and the receiving STA may correspond to an EHT STA or WUR STA. The transmitting STA of FIG. 21 may correspond to an extreme high throughput (EHT) access point (AP) or a wake up radio (WUR) AP.

In step S2110, the receiving STA (station) receives the broadcast frame from the transmitting STA. The broadcast frame may be a broadcast wake up frame, and in the embodiments herein, the broadcast frame will be described assuming a broadcast wake up frame unless otherwise specified. The transmitting STA has multiple BSSIDs (Multiple Basic Service Set IDentification).

In step S2120, the receiving STA decodes the broadcast frame.

The multiple BSSIDs include a first BSSID and a second BSSID.

The first BSSID is an identifier of a first BSS that transmits a beacon frame. The first BSSID may correspond to a Transmitted BSSID.

The second BSSID is an identifier of a second BSS except for the first BSS in all BSSs mapped to the multiple BSSIDs. The second BSSID may correspond to a nontransmitted BSSID.

Conventionally, in order to wake up the receiving STAs belonging to all BSSs mapped to the multiple BSSIDs, the transmitting STA includes each ID (the first BSSID or the second BSSID) corresponding to each of the BSSs in a wake-up frame. There has been a problem in that the WSS frame has to be repeatedly transmitted multiple times for the BSS.

In contrast, this embodiment proposes a method for a transmitting STA having multiple BSSIDs to wake up receiving STAs belonging to all BSSs mapped to multiple BSSIDs at once by transmitting a broadcast frame. The proposed method is as follows.

The broadcast frame includes an ID (IDentification) field.

The ID field is set to IDs for all the BSSs.

IDs for all the BSSs are obtained based on a transmitter ID identifying the transmitting STA.

The transmitter ID is obtained based on the first BSSID.

That is, in order to wake up all receiving STAs belonging to all BSSs of a transmitting STA having multiple BSSIDs, IDs for all the BSSs are set. Specifically, IDs for all the BSSs may be determined by subtracting Y from the transmitter ID. In this case, Y may be an integer greater than 0. As another example, IDs for all the BSSs may be determined by adding Y to the transmitter ID. At this time, the Y may be 0 or 4095.

The receiving STA is a terminal belonging to one of BSS corresponding to a transmission ID (transmitter ID) or BSS corresponding to a non-transmitter ID (ID) for all BSS calculated using the method proposed in the present invention When a frame including (all BSSs ID) is received, the corresponding terminal is regarded as a frame transmitted to it.

All terminals belonging to all of the BSS may be woken up based on the broadcast frame (particularly in the case of a broadcast wakeup frame). As a result, PCR (Primary Connectivity Radio) may be transitioned to an awake state in all terminals belonging to all the BSS.

According to the above-described embodiment, by setting the ID field of the broadcast frame to the IDs of all the BSSs, the transmitting STA can efficiently wake up the receiving STAs belonging to all the BSSs at once by transmitting one broadcast frame. It works.

The identifier of the first BSS can be obtained based on the ID of the transmitting end, and the identifier of the second BSS can be obtained based on a non-transmitter ID. The non-transmission end ID is an ID for a virtual transmission STA. A transmitting STA with multiple BSSIDs can make multiple virtual BSSs, and the virtual BSSs are collocated with each other. The receiving STA may determine that there are logically multiple APs according to the virtual BSS based on the multiple BSSIDs.

The non-transmission end ID may be determined by modulo 2 ¹² to the sum of the transmission end ID and K.

The K may be a value of the BSSID index field for the second BSS.

The broadcast frame may include a group addressed buffer field.

The group addressed buffer field may include information on whether a group addressed buffer exists to be transmitted by the transmitting STA to all terminals belonging to the BSS. That is, when there is a group addressed buffer to be transmitted by the transmitting STA to all terminals belonging to all the BSS, the group addressed buffer field may be set to 1.

The broadcast frame may further include a counter field.

The counter field may include information on whether there is a BSS parameter to be updated for all terminals belonging to the BSS. That is, when there is a BSS parameter to be updated for all terminals belonging to all the BSS, the counter field may be set to 1.

As another example, the transmitting STA may include the IDs for all the BSSs in a PCR frame or a WLAN frame (Action frame or Association response frame) and transmit the IDs to the receiving STAs. The receiving STA may check the IDs of all the BSSs, receive the broadcast frame, and decode the group addressed buffer and the counter field.

4. Device Configuration

22 shows a more detailed wireless device implementing an embodiment of the present invention. The present invention described above for the transmitting device or the receiving device can be applied to this embodiment.

The wireless device includes a processor 610, a power management module 611, a battery 612, a display 613, a keypad 614, a subscriber identification module (SIM) card 615, a memory 620, and a transceiver 630 ), one or more antennas 631, a speaker 640, and a microphone 641.

The processor 610 may be configured to implement the proposed functions, procedures and/or methods described herein. Layers of the radio interface protocol may be implemented in the processor 610. The processor 610 may include an application-specific integrated circuit (ASIC), other chipsets, logic circuits, and/or data processing devices. The processor may be an application processor (AP). The processor 610 may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modem (modulator and demodulator). Examples of processors 610 include SNAPDRAGONTM series processors manufactured by Qualcomm®, EXYNOSTM series processors manufactured by Samsung®, A series processors manufactured by Apple®, HELIOTM series processors manufactured by MediaTek®, and INTEL®. It may be an ATOMTM series processor manufactured by or a corresponding next-generation processor.

The power management module 611 manages power for the processor 610 and/or the transceiver 630. The battery 612 supplies power to the power management module 611. The display 613 outputs the results processed by the processor 610. Keypad 614 receives input to be used by processor 610. The keypad 614 may be displayed on the display 613. The SIM card 615 is an integrated circuit used to securely store an international mobile subscriber identity (IMSI) used to identify and authenticate a subscriber in a mobile phone device such as a mobile phone and a computer, and a key associated therewith. You can also store contact information on many SIM cards.

The memory 620 is operatively coupled with the processor 610, and stores various information for operating the processor 610. The memory 620 may include read-only memory (ROM), random access memory (RAM), flash memory, a memory card, a storage medium, and/or other storage devices. When the embodiment is implemented in software, the techniques described herein may be implemented as a module (eg, procedure, function, etc.) that performs the functions described herein. Modules may be stored in memory 620 and executed by processor 610. The memory 620 may be implemented inside the processor 610. Alternatively, the memory 620 may be implemented outside the processor 610 and may be communicatively connected to the processor 610 through various means known in the art.

The transceiver 630 is operatively coupled with the processor 610, and transmits and/or receives wireless signals. The transceiver 630 includes a transmitter and a receiver. The transceiver 630 may include a base band circuit for processing radio frequency signals. The transceiver controls one or more antennas 631 to transmit and/or receive wireless signals.

The speaker 640 outputs sound-related results processed by the processor 610. The microphone 641 receives sound-related inputs to be used by the processor 610.

In the case of a transmitting device, the processor 610 generates the broadcast frame and transmits the broadcast frame to a receiving STA.

In the case of a receiving device, the processor 610 receives the broadcast frame from a transmitting STA and decodes the broadcast frame.

The broadcast frame may be a broadcast wake up frame, and in the embodiments herein, the broadcast frame will be described assuming a broadcast wake up frame unless otherwise specified.

The transmitting STA has multiple BSSIDs (Multiple Basic Service Set IDentification).

The multiple BSSIDs include a first BSSID and a second BSSID.

The first BSSID is an identifier of a first BSS that transmits a beacon frame. The first BSSID may correspond to a Transmitted BSSID.

The second BSSID is an identifier of a second BSS except for the first BSS in all BSSs mapped to the multiple BSSIDs. The second BSSID may correspond to a nontransmitted BSSID.

Conventionally, in order to wake up the receiving STAs belonging to all BSSs mapped to the multiple BSSIDs, the transmitting STA includes each ID (the first BSSID or the second BSSID) corresponding to each of the BSSs in a wake-up frame. There has been a problem in that the WSS frame has to be repeatedly transmitted multiple times for the BSS.

In contrast, this embodiment proposes a method for a transmitting STA having multiple BSSIDs to wake up receiving STAs belonging to all BSSs mapped to multiple BSSIDs at once by transmitting a broadcast frame. The proposed method is as follows.

The broadcast frame includes an ID (IDentification) field.

The ID field is set to IDs for all the BSSs.

IDs for all the BSSs are obtained based on a transmitter ID identifying the transmitting STA.

The transmitter ID is obtained based on the first BSSID.

That is, in order to wake up all receiving STAs belonging to all BSSs of a transmitting STA having multiple BSSIDs, IDs for all the BSSs are set. Specifically, IDs for all the BSSs may be determined by subtracting Y from the transmitter ID. In this case, Y may be an integer greater than 0. As another example, IDs for all the BSSs may be determined by adding Y to the transmitter ID. At this time, the Y may be 0 or 4095.

The receiving STA is a terminal belonging to one of BSS corresponding to a transmission ID (transmitter ID) or BSS corresponding to a non-transmitter ID (ID) for all BSS calculated using the method proposed in the present invention When a frame including (all BSSs ID) is received, the corresponding terminal is regarded as a frame transmitted to it.

All terminals belonging to all of the BSS may be woken up based on the broadcast frame (particularly in the case of a broadcast wakeup frame). As a result, PCR (Primary Connectivity Radio) may be transitioned to an awake state in all terminals belonging to all the BSS.

According to the above-described embodiment, by setting the ID field of the broadcast frame to the IDs of all the BSSs, the transmitting STA can efficiently wake up the receiving STAs belonging to all the BSSs at once by transmitting one broadcast frame. It works.

The identifier of the first BSS can be obtained based on the ID of the transmitting end, and the identifier of the second BSS can be obtained based on a non-transmitter ID. The non-transmission end ID is an ID for a virtual transmission STA. A transmitting STA with multiple BSSIDs can make multiple virtual BSSs, and the virtual BSSs are collocated with each other. The receiving STA may determine that there are logically multiple APs according to the virtual BSS based on the multiple BSSIDs.

The non-transmission end ID may be determined by modulo 2 ¹² to the sum of the transmission end ID and K.

The K may be a value of the BSSID index field for the second BSS.

The broadcast frame may include a group addressed buffer field.

The group addressed buffer field may include information on whether a group addressed buffer exists to be transmitted by the transmitting STA to all terminals belonging to the BSS. That is, when there is a group addressed buffer to be transmitted by the transmitting STA to all terminals belonging to all the BSS, the group addressed buffer field may be set to 1.

The broadcast frame may further include a counter field.

The counter field may include information on whether there is a BSS parameter to be updated for all terminals belonging to the BSS. That is, when there is a BSS parameter to be updated for all terminals belonging to all the BSS, the counter field may be set to 1.

As another example, the transmitting STA may include the IDs for all the BSSs in a PCR frame or a WLAN frame (Action frame or Association response frame) and transmit the IDs to the receiving STAs. The receiving STA may check the IDs of all the BSSs, receive the broadcast frame, and decode the group addressed buffer and the counter field.

The technical features of the present specification described above can be applied to various application or business models. For example, the above-described technical characteristics may be applied for wireless communication in a device supporting artificial intelligence (AI).

Artificial intelligence refers to the field of studying artificial intelligence or a methodology to create it, and machine learning refers to the field of studying the methodology to define and solve various problems in the field of artificial intelligence. do. Machine learning is defined as an algorithm that improves the performance of a job through steady experience.

An artificial neural network (ANN) is a model used in machine learning, and may refer to an overall model having a problem-solving ability, composed of artificial neurons (nodes) forming a network through synaptic coupling. An artificial neural network may be defined by a connection pattern between neurons in different layers, a learning process for updating model parameters, and an activation function that generates output values.

The artificial neural network may include an input layer, an output layer, and optionally one or more hidden layers. Each layer contains one or more neurons, and an artificial neural network can include neurons and synapses connecting neurons. In an artificial neural network, each neuron may output a function value of an input function input through a synapse, a weight, and an active function for bias.

The model parameter means a parameter determined through learning, and includes weights of synaptic connections and bias of neurons. In addition, the hyperparameter means a parameter that must be set before learning in a machine learning algorithm, and includes learning rate, number of iterations, mini-batch size, initialization function, and the like.

The purpose of training an artificial neural network can be seen as determining model parameters that minimize the loss function. The loss function can be used as an index to determine an optimal model parameter in the learning process of an artificial neural network.

Machine learning can be classified into supervised learning, unsupervised learning, and reinforcement learning according to the learning method.

Supervised learning refers to a method of training an artificial neural network while a label for training data is given, and a label is a correct answer (or a result value) that the artificial neural network must infer when the training data is input to the artificial neural network. Can mean Unsupervised learning may refer to a method of training an artificial neural network without being given a label for the training data. Reinforcement learning may refer to a learning method in which an agent defined in a certain environment is trained to select an action or a sequence of actions to maximize cumulative reward in each state.

Machine learning, which is implemented as a deep neural network (DNN) that includes a plurality of hidden layers among artificial neural networks, is also referred to as deep learning (deep learning), and deep learning is part of machine learning. In the following, machine learning is used to mean deep learning.

In addition, the above-described technical features can be applied to wireless communication of the robot.

A robot can mean a machine that automatically handles or acts on a task given by its own capabilities. In particular, a robot having a function of recognizing the environment and determining an operation by itself can be referred to as an intelligent robot.

Robots can be classified into industrial, medical, household, and military according to the purpose or field of use. The robot may be provided with a driving unit including an actuator or a motor to perform various physical operations such as moving a robot joint. In addition, the movable robot includes a wheel, a brake, a propeller, and the like in the driving unit, so that it can travel on the ground or fly in the air through the driving unit.

In addition, the above-described technical features can be applied to a device that supports augmented reality.

Augmented reality refers to virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology provides objects or backgrounds in the real world only as CG images, AR technology provides CG images made virtually on real objects, and MR technology provides computers by mixing and combining virtual objects in the real world It is a graphics technology.

MR technology is similar to AR technology in that it shows both real and virtual objects. However, in AR technology, a virtual object is used as a complement to a real object, whereas in MR technology, there is a difference in that a virtual object and a real object are used with equal characteristics.

XR technology can be applied to Head-Mount Display (HMD), Head-Up Display (HUD), mobile phone, tablet PC, laptop, desktop, TV, digital signage, etc. It can be called.

The claims described herein can be combined in various ways. For example, the technical features of the method claims of the present specification may be combined and implemented as a device, and the technical features of the device claims of the specification may be combined and implemented as a method. Further, the technical features of the method claim of the present specification and the technical features of the device claim may be combined and implemented as a device, and the technical features of the method claim and the device claims of the present specification may be combined and implemented as a method.

Claims (15)

In a method for transmitting a broadcast frame in a wireless LAN (wireless LAN) system, A transmitting STA (station) having multiple BSSIDs (BSSIDs), generating the broadcast frame; And The transmitting STA, the step of transmitting the broadcast frame to the receiving STA, The multiple BSSID includes a first BSSID and a second BSSID, The first BSSID is an identifier of a first BSS that transmits a beacon frame, The second BSSID is an identifier of a second BSS excluding the first BSS in all BSSs mapped to the multiple BSSIDs, The broadcast frame includes an ID (IDentification) field, The ID field is set to IDs for all the BSSs, IDs for all the BSSs are obtained based on a transmitter ID that identifies the transmitting STA, and The transmitter ID is obtained based on the first BSSID Way. According to claim 1, The broadcast frame is a broadcast wake up frame Way According to claim 1, The IDs for all the BSSs are determined by subtracting Y from the transmitter ID, Y is an integer greater than 0 Way. According to claim 1, The receiving STA is all terminals belonging to all the BSS, Based on the broadcast frame, all terminals belonging to all the BSS are woken up Way. According to claim 1, The identifier of the second BSS is obtained based on a nontransmitter ID, The non-transmission end ID is determined by modulo 2 ¹² to the sum of the transmission end ID and K, and The K is a value of the BSSID index field for the second BSS Way. According to claim 1, The broadcast frame includes a group addressed buffer field, The group addressed buffer field includes information on whether there is a group addressed buffer to be transmitted by the transmitting STA to all terminals belonging to all the BSS. Way. The method of claim 6, The broadcast frame further includes a counter field, The counter field includes information on whether there is a BSS parameter to be updated for all terminals belonging to the BSS. Way. In a transmitting STA (station) for transmitting a broadcast frame in a wireless LAN (wireless LAN) system, the transmitting STA is Memory; Transceiver; And A processor operatively coupled to the memory and the transceiver, the processor comprising: Generate the broadcast frame; And The broadcast frame is transmitted to the receiving STA, The transmitting STA has multiple BSSIDs (Multiple Basic Service Set IDentification), The multiple BSSID includes a first BSSID and a second BSSID, The first BSSID is an identifier of a first BSS that transmits a beacon frame, The second BSSID is an identifier of a second BSS excluding the first BSS in all BSSs mapped to the multiple BSSIDs, The broadcast frame includes an ID (IDentification) field, The ID field is set to IDs for all the BSSs, IDs for all the BSSs are obtained based on a transmitter ID that identifies the transmitting STA, and The transmitter ID is obtained based on the first BSSID Send STA. The method of claim 8, The broadcast frame is a broadcast wake up frame Way The method of claim 8, The IDs for all the BSSs are determined by subtracting Y from the transmitter ID, Y is an integer greater than 0 Send STA. The method of claim 8, The receiving STA is all terminals belonging to all the BSS, Based on the broadcast frame, all terminals belonging to all the BSS are woken up Send STA. The method of claim 8, The identifier of the second BSS is obtained based on a nontransmitter ID, The non-transmission end ID is determined by modulo 2 ¹² to the sum of the transmission end ID and K, and The K is the value of the BSSID index field for the second BSS Send STA. The method of claim 8, The broadcast frame includes a group addressed buffer field, The group addressed buffer field includes information on whether there is a group addressed buffer to be transmitted by the transmitting STA to all terminals belonging to all the BSS. Send STA. The method of claim 13, The broadcast frame further includes a counter field, The counter field includes information on whether there is a BSS parameter to be updated for all terminals belonging to the BSS. Send STA. In a method for receiving a broadcast frame in a wireless LAN (wireless LAN) system, A receiving STA (station) receiving the broadcast frame from a transmitting STA; And The receiving STA, comprising the step of decoding the broadcast frame, The transmitting STA has multiple BSSIDs (Multiple Basic Service Set IDentification), The multiple BSSID includes a first BSSID and a second BSSID, The first BSSID is an identifier of a first BSS that transmits a beacon frame, The second BSSID is an identifier of a second BSS excluding the first BSS in all BSSs mapped to the multiple BSSIDs, The broadcast frame includes an ID (IDentification) field, The ID field is set to IDs for all the BSSs, IDs for all the BSSs are obtained based on a transmitter ID that identifies the transmitting STA, and The transmitter ID is obtained based on the first BSSID Way.

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