WO2024150209A1 - Sidelink resource selection for sidelink communications over a shared spectrum - Google Patents

Abstract

Various aspects of the present disclosure relate to channel occupancy time (COT) sharing for sidelink communications over unlicensed channels. For example, the systems and methods described herein enable a UE to perform efficient sidelink resource selection (or, reselection) procedures by considering or utilizing COT sharing information and/or hybrid automatic repeat request (HARQ) feedback received during sidelink transmissions (e.g., physical sidelink shared channel (PSSCH) and/or physical sidelink control channel (PSCCH) transmissions).

Description

SIDELINK RESOURCE SELECTION FOR SIDELINK COMMUNICATIONS OVER A SHARED SPECTRUM

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 63/494,107 filed on April 4, 2023, entitled SIDELINK RESOURCE SELECTION FOR SIDELINK COMMUNICATIONS OVER A SHARED SPECTRUM, which is incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] The present disclosure relates to wireless communications, and more specifically to sidelink resource selection for sidelink communications.

BACKGROUND

[0003] A wireless communications system may include one or multiple network communication devices, such as base stations, which may be otherwise known as an eNodeB (eNB), a next-generation NodeB (gNB), or other suitable terminology. Each network communication device, such as a base station, may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE), or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers). Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G)).

[0004] In some cases, network communication devices and/or user communication devices of the wireless communications system may utilize unlicensed channels or bands, such as those provided by unlicensed carriers for wireless communications. Under NR-U, or New Radio-Unlicensed applications, a communication device may access an unlicensed channel for downlink and/or uplink transmissions after performing a listen-bef ore-talk (LBT) procedure.

[0005] The communication device, such as a UE, may perform the LBT procedure by sensing the unlicensed channel for any ongoing communications within the channel (e.g., detects energy levels of sub-bands within the channel). For example, the UE (or a gNB) can initiate a channel occupancy time (COT) of the channel, which defines a time period within which the UE may communicate over the channel, by performing an LBT procedure (e.g., a category Type 1 or Type 2 procedure) and determining the channel is available for access.

[0006] In various scenarios, a UE communicates (or intends to communicate) with other UEs over a communication link called a sidelink. As the usage of such scenarios expands to additional use cases (e.g., commercial use cases), a wireless communication system may seek to increase sidelink data rates and/or support new or additional carrier frequencies for sidelink. The utilization of unlicensed spectrum can assist in achieving these objectives, providing a network with increased data rates and additional frequencies for sidelink communications.

SUMMARY

[0007] The present disclosure relates to methods, apparatuses, and systems that support a UE performing efficient sidelink resource selection (or, reselection) procedures by considering or utilizing COT sharing information and/or hybrid automatic repeat request (HARQ) feedback received during sidelink transmissions (e.g., physical sidelink shared channel (PSSCH) and/or physical sidelink control channel (PSCCH) transmissions).

[0008] Some implementations of the method and apparatuses described herein may further include a UE, comprising a processor and a memory coupled with the processor, the processor configured to cause the UE to initiate a sidelink communication with a set of UEs over an unlicensed band, wherein the sidelink communication comprises a sidelink transmission over one or more sidelink logical channels, receive an indication of a shared COT, from a COT initiating UE identified by a first identifier, determine whether the UE is eligible to utilize resource block (RB) sets of the shared COT during the sidelink transmission, and trigger a sidelink resource selection procedure upon determining the UE is eligible to utilize the RB sets of the shared COT.

[0009] In some implementations of the method and apparatuses described herein, the indication of the shared COT comprises shared COT information that includes a channel access priority class (CAPC) value for sidelink transmissions for the RB sets of the shared COT.

[0010] In some implementations of the method and apparatuses described herein, the processor is configured to cause the UE to determine the UE is eligible to utilize the RB sets of the shared COT during the sidelink transmission when a destination identifier of the sidelink transmission matches the first identifier for the COT initiating UE.

[0011] In some implementations of the method and apparatuses described herein, the processor is configured to cause the UE to determine the UE is eligible to utilize the RB sets of the shared COT during the sidelink transmission when a CAPC value for sidelink transmissions for the RB sets of the shared COT is lower or equal to a CAPC value identified by shared COT information within the indication of the shared COT.

[0012] In some implementations of the method and apparatuses described herein, each sidelink logical channel has an associated CAPC value that is based on a delay requirement for the sidelink logical channel.

[0013] In some implementations of the method and apparatuses described herein, the indication of the shared COT is received via Medium Access Control (MAC) control signaling.

[0014] In some implementations of the method and apparatuses described herein, the one or more sidelink logical channels comprise sidelink traffic channels (STCHs).

[0015] In some implementations of the method and apparatuses described herein, the processor is configured to cause the UE to initiate the sidelink communication with the set of UEs over the unlicensed band by selecting a sidelink grant. [0016] In some implementations of the method and apparatuses described herein, selecting the sidelink grant comprises performing a channel sensing procedure to determine sidelink resources available for the sidelink communication.

[0017] Some implementations of the method and apparatuses described herein may further include a method performed by a UE, the method comprising initiating a sidelink communication with a set of UEs over an unlicensed band, wherein the sidelink communication comprises a sidelink transmission over one or more sidelink logical channels, receiving an indication of a shared COT from a COT initiating UE identified by a first identifier, determining whether the UE is eligible to utilize RB sets of the shared COT during the sidelink transmission, and triggering a sidelink resource selection procedure upon determining the UE is eligible to utilize the RB sets of the shared COT.

[0018] In some implementations of the method and apparatuses described herein, the indication of the shared COT comprises shared COT information that includes a CAPC value for sidelink transmissions for the RB sets of the shared COT.

[0019] In some implementations of the method and apparatuses described herein, the UE is eligible to utilize the RB sets of the shared COT during the sidelink transmission when a destination identifier of the sidelink transmission matches the first identifier for the COT initiating UE.

[0020] In some implementations of the method and apparatuses described herein, the UE eligible to utilize the RB sets of the shared COT during the sidelink transmission when a CAPC value for sidelink transmissions for the RB sets of the shared COT is lower or equal to a CAPC value identified by shared COT information within the indication of the shared COT.

[0021] In some implementations of the method and apparatuses described herein, each sidelink logical channel has an associated CAPC value that is based on a delay requirement for the sidelink logical channel.

[0022] In some implementations of the method and apparatuses described herein, the indication of the shared COT is received via MAC control signaling. [0023] In some implementations of the method and apparatuses described herein, the one or more sidelink logical channels comprise STCHs.

[0024] In some implementations of the method and apparatuses described herein, the UE initiates the sidelink communication with the set of UEs over the unlicensed band by selecting a sidelink grant.

[0025] In some implementations of the method and apparatuses described herein, the UE selects the sidelink grant by performing a channel sensing procedure to determine sidelink resources available for the sidelink communication.

[0026] Some implementations of the method and apparatuses described herein may further include a UE, comprising a processor and a memory coupled with the processor, the processor configured to cause the UE to transmit a first stage of an indication of a shared COT that comprises shared COT information including identifiers for potential responding UEs that are eligible to utilize the shared COT for sidelink transmissions, and transmit a second stage of the indication of the shared COT that comprises the shared COT information including offset information for the shared COT.

[0027] In some implementations of the method and apparatuses described herein, the identifiers for the potential responding UEs are within a physical sidelink control channel (PSCCH) or physical sidelink shared channel (PSSCH) transmission transmitted by the UE.

[0028] In some implementations of the method and apparatuses described herein, the indication of the shared COT comprises a first stage indication and a second stage indication.

[0029] In some implementations of the method and apparatuses described herein, the UE the first stage of the indication of the shared COT is transmitted via a media access MAC CE.

[0030] In some implementations of the method and apparatuses described herein, the UE the shared COT information within the second stage of the indication of the shared COT includes a duration of the shared COT. [0031] In some implementations of the method and apparatuses described herein, the second stage of the indication of the shared COT is transmitted via downlink control information (DCI).

[0032] Some implementations of the method and apparatuses described herein may further include a method performed by a UE, the method comprising transmitting a first stage of an indication of a shared COT that comprises shared COT information including identifiers for potential responding UEs that are eligible to utilize the shared COT for sidelink transmissions, and transmitting a second stage of the indication of the shared COT that comprises the shared COT information including offset information for the shared COT.

[0033] In some implementations of the method and apparatuses described herein, the identifiers for the potential responding UEs are within a PSCCH or PSSCH transmission transmitted by the UE.

[0034] In some implementations of the method and apparatuses described herein, the indication of the shared COT comprises a first stage indication and a second stage indication.

[0035] In some implementations of the method and apparatuses described herein, the first stage of the indication of the shared COT is transmitted via a MAC CE.

[0036] In some implementations of the method and apparatuses described herein, the shared COT information within the second stage of the indication of the shared COT includes a duration of the shared COT.

[0037] In some implementations of the method and apparatuses described herein, the second stage of the indication of the shared COT is transmitted via DCI.

[0038] Some implementations of the method and apparatuses described herein may further include a processor for wireless communication, comprising at least one controller coupled with at least one memory and configured to cause the processor to initiate a sidelink communication with a set of UEs over an unlicensed band, wherein the sidelink communication comprises a sidelink transmission over one or more sidelink logical channels, receive an indication of a shared COT from a COT initiating UE identified by a first identifier, determine whether the UE is eligible to utilize RB sets of the shared COT during the sidelink transmission, and trigger a sidelink resource selection procedure upon determining the processor is eligible to utilize the RB sets of the shared COT.

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG. 1 illustrates an example of a wireless communications system that supports sidelink resource selection for sidelink communications in accordance with aspects of the present disclosure.

[0040] FIG. 2 illustrates an example of a wireless communications system selecting a resource selection operation in accordance with aspects of the present disclosure.

[0041] FIG. 3A illustrates an example of a diagram that supports an example resource selection timeline in accordance with aspects of the present disclosure.

[0042] FIG. 3B illustrates an example of a diagram that supports a shared COT in accordance with aspects of the present disclosure.

[0043] FIG. 4 illustrates an example of a block diagram of a device that supports sidelink resource selection for sidelink communications in accordance with aspects of the present disclosure.

[0044] FIG. 5 illustrates a flowchart of a method that supports selecting a sidelink resource selection procedure in accordance with aspects of the present disclosure.

[0045] FIG. 6 illustrates a flowchart of a method that supports a two-stage COT sharing indication in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

[0046] When a UE performs a sidelink resource selection procedure, the UE may consider LBT impact to or from resources reserved by other UEs. Further, the UE may consider, during the resource (re)selection procedure, LBT impacts to its own candidate resources.

[0047] The systems and methods described herein enable a UE to perform efficient sidelink resource selection (or, reselection) procedures by considering or utilizing COT sharing information and/or hybrid automatic repeat request (HARQ) feedback received during sidelink transmissions (e.g., physical sidelink shared channel (PSSCH) and/or physical sidelink control channel (PSCCH) transmissions).

[0048] For example, the UE may consider and/or base a sidelink resource selection operation on COT sharing information, to maximize usage of a shared COT (e.g., a COT shared by another UE, such as a COT initiating UE), improving a user’s experience by reducing or minimizing failures associated with LBT procedures that attempt to gain access to a COT, such as a new COT.

[0049] For example, the resource selection operation may, based on received COT sharing information, performing a certain type of LBT, such as a short LBT operation (e.g., type 2) in place of a contention window (CW) based sensing operation (e.g., type 1), associated with the UE initiating its own COT. Thus, the UE, when eligible to share a COT, may modify its resource selection operations or procedures to perform a more efficient procedure (e.g., switch to a type 2 procedure) upon receiving the COT sharing information, among other benefits. For example, initiating a COT may involve a certain sensing time before transmissions are allowed, while starting transmission in a shared COT may include no such sensing or only a fraction of the sensing time required for initiating a COT.

[0050] Aspects of the present disclosure are described in the context of a wireless communications system. Aspects of the present disclosure are further illustrated and described with reference to device diagrams and flowcharts.

[0051] FIG. 1 illustrates an example of a wireless communications system 100 that supports sidelink resource selection for sidelink communications in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more network entities 102, one or more UEs 104, a core network 106, and a packet data network 108. The wireless communications system 100 may support various radio access technologies. In some implementations, the wireless communications system 100 may be a 4G network, such as an LTE network or an LTE- Advanced (LTE-A) network. In some other implementations, the wireless communications system 100 may be a 5G network, such as an NR network. In other implementations, the wireless communications system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20. The wireless communications system 100 may support radio access technologies beyond 5G. Additionally, the wireless communications system 100 may support technologies, such as time division multiple access (TDMA), frequency division multiple access (FDMA), or code division multiple access (CDMA), etc.

[0052] The one or more network entities 102 may be dispersed throughout a geographic region to form the wireless communications system 100. One or more of the network entities 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a radio access network (RAN), a base transceiver station, an access point, a NodeB, an eNodeB (eNB), a next-generation NodeB (gNB), or other suitable terminology. A network entity 102 and a UE 104 may communicate via a communication link 110, which may be a wireless or wired connection. For example, a network entity 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

[0053] A network entity 102 may provide a geographic coverage area 112 for which the network entity 102 may support services (e.g., voice, video, packet data, messaging, broadcast, etc.) for one or more UEs 104 within the geographic coverage area 112. For example, a network entity 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc.) according to one or multiple radio access technologies. In some implementations, a network entity 102 may be moveable, for example, a satellite associated with a non-terrestrial network. In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas 112 may be associated with different network entities 102. Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0054] The one or more UEs 104 may be dispersed throughout a geographic region of the wireless communications system 100. A UE 104 may include or may be referred to as a mobile device, a wireless device, a remote device, a remote unit, a handheld device, or a subscriber device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Internet-of-Things (loT) device, an Internet-of-Everything (loE) device, or machine-type communication (MTC) device, among other examples. In some implementations, a UE 104 may be stationary in the wireless communications system 100. In some other implementations, a UE 104 may be mobile in the wireless communications system 100.

[0055] The one or more UEs 104 may be devices in different forms or having different capabilities. Some examples of UEs 104 are illustrated in FIG. 1. A UE 104 may be capable of communicating with various types of devices, such as the network entities 102, other UEs 104, or network equipment (e.g., the core network 106, the packet data network 108, a relay device, an integrated access and backhaul (IAB) node, or another network equipment), as shown in FIG. 1. Additionally, or alternatively, a UE 104 may support communication with other network entities 102 or UEs 104, which may act as relays in the wireless communications system 100.

[0056] A UE 104 may also be able to support wireless communication directly with other UEs 104 over a communication link 114. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface. [0057] A network entity 102 may support communications with the core network 106, or with another network entity 102, or both. For example, a network entity 102 may interface with the core network 106 through one or more backhaul links 116 (e.g., via an SI, N2, N2, or another network interface). The network entities 102 may communicate with each other over the backhaul links 116 (e.g., via an X2, Xn, or another network interface). In some implementations, the network entities 102 may communicate with each other directly (e.g., between the network entities 102). In some other implementations, the network entities 102 may communicate with each other or indirectly (e.g., via the core network 106). In some implementations, one or more network entities 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC). An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or transmission-reception points (TRPs).

[0058] In some implementations, a network entity 102 may be configured in a disaggregated architecture, which may be configured to utilize a protocol stack physically or logically distributed among two or more network entities 102, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance), or a virtualized RAN (vRAN) (e.g., a cloud RAN (C- RAN)). For example, a network entity 102 may include one or more of a central unit (CU), a distributed unit (DU), a radio unit (RU), a RAN Intelligent Controller (RIC) (e.g., a NearReal Time RIC (Near-RT RIC), a Non-Real Time RIC (Non-RT RIC)), a Service Management and Orchestration (SMO) system, or any combination thereof.

[0059] An RU may also be referred to as a radio head, a smart radio head, a remote radio head (RRH), a remote radio unit (RRU), or a transmission reception point (TRP). One or more components of the network entities 102 in a disaggregated RAN architecture may be co-located, or one or more components of the network entities 102 may be located in distributed locations (e.g., separate physical locations). In some implementations, one or more network entities 102 of a disaggregated RAN architecture may be implemented as virtual units (e.g., a virtual CU (VCU), a virtual DU (VDU), a virtual RU (VRU)). [0060] Split of functionality between a CU, a DU, and an RU may be flexible and may support different functionalities depending upon which functions (e.g., network layer functions, protocol layer functions, baseband functions, radio frequency functions, and any combinations thereof) are performed at a CU, a DU, or an RU. For example, a functional split of a protocol stack may be employed between a CU and a DU such that the CU may support one or more layers of the protocol stack and the DU may support one or more different layers of the protocol stack. In some implementations, the CU may host upper protocol layer (e.g., a layer 3 (L3), a layer 2 (L2)) functionality and signaling (e.g., Radio Resource Control (RRC), service data adaption protocol (SDAP), Packet Data Convergence Protocol (PDCP)). The CU may be connected to one or more DUsor RUs, and the one or more DUs or RUs may host lower protocol layers, such as a layer 1 (LI) (e.g., physical (PHY) layer) or an L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling and may each be at least partially controlled by the CU 160.

[0061] Additionally, or alternatively, a functional split of the protocol stack may be employed between a DU and an RU such that the DU may support one or more layers of the protocol stack and the RU may support one or more different layers of the protocol stack. The DU may support one or multiple different cells (e.g., via one or more RUs). In some implementations, a functional split between a CU and a DU, or between a DU and an RU may be within a protocol layer (e.g., some functions for a protocol layer may be performed by one of a CU, a DU, or an RU, while other functions of the protocol layer are performed by a different one of the CU, the DU, or the RU).

[0062] A CU may be functionally split further into CU control plane (CU-CP) and CU user plane (CU-UP) functions. A CU may be connected to one or more DUs via a midhaul communication link (e.g., Fl, Fl-c, Fl-u), and a DU may be connected to one or more RUs via a fronthaul communication link (e.g., open fronthaul (FH) interface). In some implementations, a midhaul communication link or a fronthaul communication link may be implemented in accordance with an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 102 that are in communication via such communication links. [0063] The core network 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The core network 106 may be an evolved packet core (EPC), or a 5G core (5GC), which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME), an access and mobility management functions (AMF)) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW), a Packet Data Network (PDN) gateway (P-GW), or a user plane function (UPF)). In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc.) for the one or more UEs 104 served by the one or more network entities 102 associated with the core network 106.

[0064] The core network 106 may communicate with the packet data network 108 over one or more backhaul links 116 (e.g., via an SI, N2, N2, or another network interface). The packet data network 108 may include an application server 118. In some implementations, one or more UEs 104 may communicate with the application server 118. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the core network 106 via a network entity 102. The core network 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application server 118 using the established session (e.g., the established PDU session). The PDU session may be an example of a logical connection between the UE 104 and the core network 106 (e.g., one or more network functions of the core network 106).

[0065] In the wireless communications system 100, the network entities 102 and the UEs 104 may use resources of the wireless communication system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers)) to perform various operations (e.g., wireless communications). In some implementations, the network entities 102 and the UEs 104 may support different resource structures. For example, the network entities 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the network entities 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the network entities 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures). The network entities 102 and the UEs 104 may support various frame structures based on one or more numerologies.

[0066] One or more numerologies may be supported in the wireless communications system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., /r=0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., /r=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., /r=l) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., /r=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., /r=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., /r=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

[0067] A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames). Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

[0068] Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., /r=0, jU=l, /r=2, jU=3, /r=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., OFDM symbols). In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing), a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., /r=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

[0069] In the wireless communications system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz - 7.125 GHz), FR2 (24.25 GHz - 52.6 GHz), FR3 (7.125 GHz - 24.25 GHz), FR4 (52.6 GHz - 114.25 GHz), FR4a or FR4-1 (52.6 GHz - 71 GHz), and FR5 (114.25 GHz - 300 GHz). In some implementations, the network entities 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the network entities 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data). In some implementations, FR2 may be used by the network entities 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

[0070] FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies). For example, FR1 may be associated with a first numerology (e.g., /r=0), which includes 15 kHz subcarrier spacing; a second numerology (e.g., /r=l), which includes 30 kHz subcarrier spacing; and a third numerology (e.g., /r=2), which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies). For example, FR2 may be associated with a third numerology (e.g., /r=2), which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., /r=3), which includes 120 kHz subcarrier spacing. [0071] As described herein, in some embodiments, a UE, such as the UE 104, can modify resource selection operations and/or select efficient resource selection procedures (e.g., LBT procedures) based on receiving COT sharing information associated with a COT available for sharing that is initiated by another UE.

[0072] FIG. 2 illustrates an example of a wireless communications system 200 that supports selecting a resource selection operation in accordance with aspects of the present disclosure. The wireless communications system 200 may implement or be implemented by aspects of the wireless communications system 100 as described in FIG. 1. For example, the wireless communications system 200 may include a base station 102 and a UE 104, which may be examples of base stations and UEs 104 as described with reference to FIG. 1.

[0073] A responding UE 210 receives an indication of a shared COT (e.g., a COT sharing indication 240) from a COT initiating UE 220, which initiated a COT 230 over an unlicensed channel for sidelink communications. In some cases, the COT sharing indication 240 may include destination information and/or a channel access priority class (CAPC) value for data to be transmitted over the shared COT 230 by the responding UE 210.

[0074] The responding UE 210, in some embodiments, triggers a resource selection operation 250 upon receiving the COT sharing indication 240 (e.g., having COT sharing information) from the COT initiating UE 220. Using the COT sharing information, the responding UE 210 performs resource selection, or resource reselection, even after a previous selection of resources to be used for data transmission (e.g., PSSCH/PSCCH transmission).

[0075] In some cases, reception of the COT sharing information (e.g., via the COT sharing indication 240) triggers the responding UE 210 to perform a new or updated resource selection operation. The responding UE 210 may consider, in combination, inter- UE coordination information along with the COT sharing information when selecting resources. For example, based on receiving the COT sharing information, the responding UE 210 may perform an LBT type 2 operation for transmissions within a shared COT 230, instead of initiating a new COT (using a LBT type 1 operation). [0076] Further, in some cases, the responding UE 210 may determine its eligibility for using the shared COT before triggering the resource (re)sel ection operation. For example, the responding UE 210 may satisfy various COT usage conditions (e.g., destination and/or CAPC conditions) before performing resource reselection operations based on received COT sharing information.

[0077] FIG. 3A illustrates an example of a diagram 300 that supports an example resource selection timeline in accordance with aspects of the present disclosure. At a time Tl, a UE has selected resources for data transmission. At a time T2, the UE receives COT sharing information, which identifies resources available within a shared COT, such as the COT 230. At a time T3, the UE performs a logical channel prioritization (LCP) procedure using the selected resources.

[0078] In some cases, when the UE triggers the resource (re)selection in response to the reception of the COT sharing information, the usage of the shared COT 230 is maximized. Further, other layer 2 procedures (e.g., discontinuous reception, or DRX, operations) may benefit from the optimized shared COT usage. For example, COT sharing between UEs can lead to predicable UE behaviors, facilitating switching to power saving modes of operation (e.g., DRX), among other benefits.

[0079] In some embodiments, a MAC layer may provide CAPC information, for resource selection operations, to the physical (PHY) layer. For example, in addition to providing delay budget information, the MAC layer may provide the CAPC information to the PHY layer. An example implementation is as follows (with reference to TS 38.214):

[0080] In resource allocation mode 2, the higher layer can request the UE to determine a subset of resources from which the higher layer will select resources for PSSCH/PSCCH transmission. To trigger this procedure, in slot n, the higher layer provides the following parameters for this PSSCH/PSCCH transmission:

- the resource pool from which the resources are to be reported;

- LI priority, prio_TX

- the remaining packet delay budget;

CAPC value associated with the PSSCH transmission (TB); - the number of sub-channels to be used for the PSSCH/PSCCH transmission in a slot, ^subCH,

- optionally, the resource reservation interval, P_rsvp TX, in units of msec.

[0081] In some embodiments, a UE may trigger resource (re)selection based on the content of a physical sidelink feedback channel (PSFCH) received for a PSSCH transmission. Since CAPC information used for resource selection may change based on the received feedback (ACK/NACK), the UE may trigger resource reselection in response to the PSFCH content.

[0082] In some cases, when a NACK is received for a PSSCH transmission, the same CAPC value as for the previous HARQ transmission of the same TB is used for the retransmission. In some other cases, such as when ACK is received for a PSSCH transmission, the UE may generate a new TB, which may have a different associated CAPC. The UE, when performing an initial resource selection operation, may not know how many retransmissions may occur for a TB/PSSCH transmission. Thus, it may not be possible for the UE to accurately predict the CAPC value to be used for a PSSCH transmission and to accurately assume a CW size for the corresponding PSSCH transmission.

[0083] In some cases, the duration of both the COT and the CW depends on the CAPC associated with the UE’s traffic (see TS 37.213). Therefore, the UE may perform a resource reselection based on the changed CAPC. For example, the UE triggers a resource selection operation when the CAPC value associated with a PSSCH transmission is greater than a CAPC value assumed or determined for the resource selection.

[0084] The sidelink resource selection operation may consider a current channel access mechanism to reduce LBT failures. For example, when a UE selects a candidate resource before a previous reserved resource that is indicated via shared COT information received via another UE and transmission of symbols of the selected candidate resource overlap with an LBT interval for transmission in the reserved resource, the selection may cause an LBT failure at the other UE, which may lose a high priority packet. [0085] In accord with agreements (e.g., RAN2) for sidelink unlicensed procedures, the UE may trigger resource (re)selection for a CAPC assumed for an initial resource selection for a PSSCH transmission changes upon reception of PSFCH (ACK/NACK). For example, the UE assumes a NACK (e.g., the PSSCH carries a HARQ retransmission), but the ACK was received by the UE (e.g., the PSSCH transmission carries a new TB).

[0086] In some embodiments, the UE may only consider logical channels associated with a CAPC value during the LCP procedure for generation of a new TB that match the CAPC value assumed when performing initially the resource selection for the corresponding PSSCH transmission. For example, the UE may assume one CAPC value for one resource selection process, despite multiple resources being selected for multiple MAC PDUs/TBs.

[0087] In some embodiments, a minimum time gap between two selected resources may account for a time required to perform an LBT procedure. For example, a minimum time gap may be set as a time between a last symbol of a PSSCH transmission and a corresponding starting symbol of a PSFCH transmission plus processing time for PSFCH decoding and sidelink retransmission preparation time.

[0088] In some cases, the minimum time gap between two selected resources may also be based on the LBT period for a sidelink retransmission. Since the LBT period depends on the CAPC value of the associated TB or the CW (e.g., for cases when LBT type 1 is performed, the minimum time gap can have different values. The UE, therefore, may determine the time to perform LBT for a sidelink retransmission.

[0089] In some embodiments, the UE may send the COT sharing Information at a predefined time before the start of the first symbol of the shared COT resource. For example, in some cases, the UE is not allowed to send a COT sharing indication, which includes an offset (e.g., leading to a sidelink starting position for a sidelink transmission within a COT) an offset before the start of the shared COT that is less than a predefined minimum offset.

[0090] To ensure a potential responding UE can consider received COT sharing information during an LCP procedure for a first PSSCH transmission within a shared COT, the COT sharing information may be sent at least a predefined time period before the start of the shared COT, such as the start of a first symbol of the first PSCCH/PSSCH transmission resource within the shared COT.

[0091] For example, the predefined time may be equal to the minimum processing time of the shared COT information. The predefined time may be a time required for COT sharing indication reception and processing plus a time required for performing the LCP procedure and generating a transport block for a PSSCH transmission (e.g., T_proc). For example, as set forth in TS 38.214 clause 8.6, a UE may utilize a time period of T_proc for PDU generation and LI processing (e.g., for 30kHz, T_proc = 13 symbols).

[0092] In some embodiments, the shared COT information may indicate an offset that points to the start of the shared COT (e.g., an offset pointing to the starting symbol of the first resource of the shared COT). In some cases, the offset may be greater than or equal to a predefined minimum time, such as a time required for COT sharing indication reception and processing plus the time required for performing an LCP procedure and generating a transport block for a PSSCH transmission.

[0093] In some cases, introduction of a minimum time before the start of a shared COT enables a responding UE to perform an enhanced LCP procedure, allowing the responding UE to use the shared COT (e.g., when a destination ID matches the source ID of the COT initiating UE) and CAPC associated with the generated TB satisfies the CAPC requirements signaled with the COT sharing information.

[0094] In some embodiments, the UE performs a repetition of PSSCH transmission(s) in order to ensure that the time period between the slots, where a COT sharing indication has been sent by the initiating UE and the starting symbol of the shared COT is occupied by PSSCH transmission. In some cases, such as when the initiating UE does not have any available data for a PSSCH before the starting symbol of the shared COT (assuming that the COT sharing indication has been sent at least a predefined minimum time before the starting symbol of the shared COT), the initiating UE repeats a previous PSSCH transmission to ensure that the channel is maintained by the UE. [0095] FIG. 3B illustrates an example of a diagram that supports a shared COT 350 in accordance with aspects of the present disclosure. An initiating UE acquires the COT 350 in slot n and performs 2 PSSCH transmissions in the first two slots 360, 365 of the COT 350. In a second slot 365 (e.g., at the beginning of the second slot) the initiating UE sends a shared COT indication message to a responding UE. The offset within the shared COT information indicates a beginning (e.g., a starting symbol of the first slot of the shared COT 350), which signals that the shared COT starts at slot 5. Since the offset is based on a predefined minimum processing time, as described herein, the earliest point in time where the shared COT can start is a fifth slot 370.

[0096] However, since the initiating UE has only data available for a PSSCH transmission for the first two slots of the acquired COT, slot 3 and slot 4 may be empty, and other devices could take over the channel. Therefore, in some cases, the initiating UE may a repetition of a previous PSSCH transmission (e.g., the PSSCH transmission in slot 1 or slot 2), in the empty slots 375, 380 (e.g., slots 3 and 4) to maintain access to the channel.

[0097] In some embodiments, a COT sharing indication, such as the COT sharing information, may be split into two stages or messages, and be transmitted as a two-stage COT sharing indication. For example, a first part/stage of the COT sharing information may include IDs that a potential responding UE may match for its sidelink transmission(s) to be eligible to use the shared COT. The responding UE over a shared COT may be a receiving UE or a responding UE, which is the target of a PSCCH/PSSCH transmission of a COT initiating UE.

[0098] In some cases, the COT initiating UE sends a unicast message within the COT, where the source and destination IDs contained in the COT initiator’s Sidelink Control Information (SCI) match to corresponding destination and source IDs for a same unicast at the receiving UE. In some cases, the COT initiating UE sends a groupcast or broadcast message within the COT, where the destination ID contained in the COT initiator’s SCI match a destination ID known at the receiving UE. In some cases, a responding UE over a shared COT can be a UE identified by ID(s), when additional IDs are included in the COT sharing information from the COT initiator (in addition to the source and destination IDs of the PSCCH/PSSCH transmission). For example, the additional IDs may be transmitted with the first stage of the COT sharing information, such as via a MAC CE.

[0099] In some cases, the second stage of the COT sharing information can include offset information and/or a duration of the shared COT. Such information can be transmitted via the SCI.

[0100] In some embodiments, a UE may treat an LBT failure for a PSSCH transmission as if no HARQ feedback is/was received for a corresponding sidelink HARQ process. For example, when a PSSCH transmission cannot be performed due to an LBT failure, and the PSFCH is configured, the UE acts as if no corresponding PSFCH is received for the PSSCH. The UE may deliver a negative acknowledgement to the corresponding sidelink HARQ entity for the sidelink process when a PSSCH transmission cannot take place due to the LBT failure.

[0101] In some cases, the UE may deliver a NACK to the corresponding sidelink HARQ entity for the sidelink process when the UE doesn’t receive an ACK for the corresponding PSSCH transmission attempt. The UE, therefore, may trigger an (autonomous) retransmission when there is an LBT failure occurring for a PSSCH transmission.

[0102] Thus, in various embodiments, the systems and methods described herein enable a UE to perform efficient sidelink resource selection (or, reselection) procedures by considering or utilizing COT sharing information and/or HARQ feedback received during sidelink transmissions. The systems and methods can facilitate following implementations.

[0103] As a first example, a UE may trigger resource reselection operations based on a COT sharing indication. For example, the reception of a shared COT indication may be a new trigger for sidelink resource (re)selection, where a UE determines whether it is eligible for the usage of the shared COT and triggers the sidelink resource (re)selection in response to having determined that it is allowed to perform a SL transmission on the indicated shared COT.

[0104] As another example, a UE may perform sidelink resource reselection based on PSFCH reception. For example, for sidelink resource selection, a MAC layer may provide CAPC to a PHY layer, so that PHY layer can consider LBT impacts from/to other UEs. Since the CAPC value for a PSSCH/PSCCH transmission depends on the HARQ feedback of a previous PSSCH transmission, the UE may trigger resource (re)selection procedures with updated CAPC values. The trigger resource reselection may be based on PCFCH content (ACK/NACK).

[0105] As another example, a minimum time gap between any two resources may account for an LBT period required for the sidelink retransmission.

[0106] As another example when there is an LBT failure of PSSCH transmission with a PSFCH configuration, the UE may treat the PSSCH transmission and having occurred with no received feedback, and, in some cases, autonomous PSSCH retransmission may be triggered.

[0107] As another example, there may be a minimum processing time for the COT sharing indication. The initiating UE may send the shared COT indication at a predefined minimum time before the start of the shared COT, and a responding UE may perform an LCP procedure based on the shared COT indication. The initiating UE may perform repetition of previous PSSCH transmission(s) to ensure that the time period between slots where a COT sharing indication has been sent by the initiating UE and the starting symbol of the shared COT is occupied by PSSCH transmission.

[0108] As another example, a COT sharing indication may be sent as separate messages (e.g., as a two-stage shared COT indication).

[0109] FIG. 4 illustrates an example of a block diagram 400 of a device 402 that supports sidelink resource selection for sidelink communications in accordance with aspects of the present disclosure. The device 402 may be an example of a network entity 102 or UE 104 as described herein. The device 402 may support wireless communication with one or more network entities 102, UEs 104, or any combination thereof. The device 402 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 404, a memory 406, a transceiver 408, and an I/O controller 410. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses).

[0110] The processor 404, the memory 406, the transceiver 408, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 404, the memory 406, the transceiver 408, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

[0111] In some implementations, the processor 404, the memory 406, the transceiver 408, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry). The hardware may include a processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field- programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 404 and the memory 406 coupled with the processor 404 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 404, instructions stored in the memory 406).

[0112] For example, the processor 404 may support wireless communication at the device 402 in accordance with examples as disclosed herein. The processor 404 may be configured as or otherwise support a means for initiating a sidelink communication with a set of UEs over an unlicensed band, where the sidelink communication comprises a sidelink transmission over one or more sidelink logical channels, receiving an indication of a shared COT from a COT initiating UE identified by a first identifier, determining whether the UE is eligible to utilize RB sets of the shared COT during the sidelink transmission, and triggering a sidelink resource selection procedure upon determining the UE is eligible to utilize the RB sets of the shared COT.

[0113] As another example, the processor 404 may support wireless communication at the device 402 in accordance with examples as disclosed herein. The processor 404 may be configured as or otherwise support a means for transmitting a first stage of an indication of a shared COT that comprises shared COT information including identifiers for potential responding UEs that are eligible to utilize the shared COT for sidelink transmissions, and transmitting a second stage of the indication of the shared COT that comprises the shared COT information including offset information for the shared COT.

[0114] The processor 404 may include an intelligent hardware device (e.g., a general- purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some implementations, the processor 404 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 404. The processor 404 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 406) to cause the device 402 to perform various functions of the present disclosure.

[0115] The memory 406 may include random access memory (RAM) and read-only memory (ROM). The memory 406 may store computer-readable, computer-executable code including instructions that, when executed by the processor 404 cause the device 402 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 404 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 406 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

[0116] The I/O controller 410 may manage input and output signals for the device 402. The I/O controller 410 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 410 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 410 may utilize an operating system such as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operating system. In some implementations, the I/O controller 410 may be implemented as part of a processor, such as the processor M06. In some implementations, a user may interact with the device 402 via the I/O controller 410 or via hardware components controlled by the I/O controller 410.

[0117] In some implementations, the device 402 may include a single antenna 412. However, in some other implementations, the device 402 may have more than one antenna 412 (i.e., multiple antennas), including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 408 may communicate bi-directionally, via the one or more antennas 412, wired, or wireless links as described herein. For example, the transceiver 408 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 408 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 412 for transmission, and to demodulate packets received from the one or more antennas 412.

[0118] FIG. 5 illustrates a flowchart of a method 500 that supports selecting a sidelink resource selection procedure in accordance with aspects of the present disclosure. The operations of the method 500 may be implemented by a device or its components as described herein. For example, the operations of the method 500 may be performed by the UE 104 as described with reference to FIGs. 1 through 3B. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

[0119] At 505, the method 500 may include initiating a sidelink communication with a set of UEs over an unlicensed band, where the sidelink communication comprises a sidelink transmission over one or more sidelink logical channels. The operations of 505 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 505 may be performed by a device as described with reference to FIG. 1.

[0120] At 510, the method 500 may include receiving an indication of a shared COT from a COT initiating UE identified by a first identifier. The operations of 510 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 510 may be performed by a device as described with reference to FIG. 1.

[0121] At 515, the method 500 may include determining whether the UE is eligible to utilize RB sets of the shared COT during the sidelink transmission. The operations of 515 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 515 may be performed by a device as described with reference to FIG. 1.

[0122] At 520, the method 500 may include triggering a sidelink resource selection procedure upon determining the UE is eligible to utilize the RB sets of the shared COT. The operations of 520 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 520 may be performed by a device as described with reference to FIG. 1.

[0123] FIG. 6 illustrates a flowchart of a method 600 that supports a two-stage COT sharing indication in accordance with aspects of the present disclosure. The operations of the method 600 may be implemented by a device or its components as described herein. For example, the operations of the method 600 may be performed by the UE 104 as described with reference to FIGs. 1 through 3B. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

[0124] At 605, the method 600 may include transmitting a first stage of an indication of a shared COT that comprises shared COT information including identifiers for potential responding UEs that are eligible to utilize the shared COT for sidelink transmissions. The operations of 605 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 605 may be performed by a device as described with reference to FIG. 1.

[0125] At 610, the method 600 may include transmitting a second stage of the indication of the shared COT that comprises the shared COT information including offset information for the shared COT. The operations of 610 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 610 may be performed by a device as described with reference to FIG. 1.

[0126] It should be noted that the methods described herein describes possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

[0127] The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0128] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

[0129] Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

[0130] Any connection may be properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer- readable media.

[0131] As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of’ or “one or more of’ or “one or both of’) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. Further, as used herein, including in the claims, a “set” may include one or more elements.

[0132] The terms “transmitting,” “receiving,” or “communicating,” when referring to a network entity, may refer to any portion of a network entity (e.g., a base station, a CU, a DU, a RU) of a RAN communicating with another device (e.g., directly or via one or more other network entities).

[0133] The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “example” used herein means “serving as an example, instance, or illustration,” and not “preferred” or “advantageous over other examples.” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described example.

[0134] The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

CLAIMS What is claimed is:

1. A user equipment (UE), comprising: at least one memory; and at least one processor coupled to the at least one memory and configured to cause the UE to: initiate a sidelink communication with a set of UEs over an unlicensed band, wherein the sidelink communication comprises a sidelink transmission over one or more sidelink logical channels; receive an indication of a shared channel occupancy time (COT) from a COT initiating UE identified by a first identifier; determine whether the UE is eligible to utilize resource block (RB) sets of the shared COT during the sidelink transmission; and trigger a sidelink resource selection procedure upon determining the UE is eligible to utilize the RB sets of the shared COT.

2. The UE of claim 1, wherein the indication of the shared COT comprises shared COT information that includes a channel access priority class (CAPC) value for sidelink transmissions for the RB sets of the shared COT.

3. The UE of claim 1, wherein the at least one processor is configured to cause the UE to determine the UE is eligible to utilize the RB sets of the shared COT during the sidelink transmission when a destination identifier of the sidelink transmission matches the first identifier for the COT initiating UE.

4. The UE of claim 1, wherein the at least one processor is configured to cause the UE to determine the UE is eligible to utilize the RB sets of the shared COT during the sidelink transmission when a channel access priority class (CAPC) value for sidelink transmissions for the RB sets of the shared COT is lower or equal to a CAPC value identified by shared COT information within the indication of the shared COT.

5. The UE of claim 4, wherein each sidelink logical channel has an associated CAPC value that is based on a delay requirement for the sidelink logical channel.

6. The UE of claim 1, wherein the indication of the shared COT is received via Medium Access Control (MAC) control signaling.

7. The UE of claim 1, wherein the one or more sidelink logical channels comprise sidelink traffic channels (STCHs).

8. The UE of claim 1, wherein the at least one processor is configured to cause the UE to initiate the sidelink communication with the set of UEs over the unlicensed band by selecting a sidelink grant.

9. The UE of claim 8, wherein selecting the sidelink grant comprises performing a channel sensing procedure to determine sidelink resources available for the sidelink communication.

10. A method performed by a user equipment (UE), the method comprising: initiating a sidelink communication with a set of UEs over an unlicensed band, wherein the sidelink communication comprises a sidelink transmission over one or more sidelink logical channels; receiving an indication of a shared channel occupancy time (COT) from a COT initiating UE identified by a first identifier; determining whether the UE is eligible to utilize resource block (RB) sets of the shared COT during the sidelink transmission; and triggering a sidelink resource selection procedure upon determining the UE is eligible to utilize the RB sets of the shared COT.

11. The method of claim 10, wherein the indication of the shared COT comprises shared COT information that includes a channel access priority class (CAPC) value for sidelink transmissions for the RB sets of the shared COT.

12. The method of claim 10, wherein the UE is eligible to utilize the RB sets of the shared COT during the sidelink transmission when a destination identifier of the sidelink transmission matches the first identifier for the COT initiating UE.

13. The method of claim 10, wherein the UE eligible to utilize the RB sets of the shared COT during the sidelink transmission when a channel access priority class (CAPC) value for sidelink transmissions for the RB sets of the shared COT is lower or equal to a CAPC value identified by shared COT information within the indication of the shared COT.

14. A user equipment (UE), comprising: at least one memory; and at least one processor coupled to the at least one memory and configured to cause the UE to: transmit a first stage of an indication of a shared channel occupancy time (COT) that comprises shared COT information including identifiers for potential responding UEs that are eligible to utilize the shared COT for sidelink transmissions; and transmit a second stage of the indication of the shared COT that comprises the shared COT information including offset information for the shared COT.

15. The UE of claim 14, wherein the identifiers for the potential responding UEs are within a physical sidelink control channel (PSCCH) or physical sidelink shared channel (PSSCH) transmission transmitted by the UE.

16. The UE of claim 14, wherein the indication of the shared COT comprises a first stage indication and a second stage indication.

17. The UE of claim 16, wherein the first stage of the indication of the shared COT is transmitted via a media access control control element (MAC CE).

18. The UE of claim 17, wherein the shared COT information within the second stage of the indication of the shared COT includes a duration of the shared COT.

19. The UE of claim 17, wherein the second stage of the indication of the shared COT is transmitted via downlink control information (DCI).

20. A processor for wireless communication, comprising: at least one controller coupled with at least one memory and configured to cause the processor to: initiate a sidelink communication with a set of UEs over an unlicensed band, wherein the sidelink communication comprises a sidelink transmission over one or more sidelink logical channels; receive an indication of a shared channel occupancy time (COT) from a COT initiating UE identified by a first identifier; determine whether the UE is eligible to utilize resource block (RB) sets of the shared COT during the sidelink transmission; and trigger a sidelink resource selection procedure upon determining the processor is eligible to utilize the RB sets of the shared COT.