Resource allocation for channel occupancy time sharing in mode two-side link communications

Abstract

Wireless communication systems, apparatuses, and methods are provided. A method of wireless communication performed by a first sidelink user equipment (UE) may include performing a first listen before talk (LBT) procedure; transmitting, to a second sidelink UE based on the first LBT procedure being successful, at least one of: a resource indicator indicating a resource associated with a sidelink communication, wherein the resource is indicated relative to when the first LBT procedure is successful; or a channel occupancy time (COT) indicator associated with the channel occupancy time (COT) sharing.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Patent Application No. 17 / 807,045, filed on June 15, 2022, the disclosure of which is incorporated herein by reference as if fully set forth below and for all applicable purposes. Technical Field

[0003] The present application relates to wireless communication systems, and more particularly to resource allocation for channel occupancy time (COT) sharing in mode two sidelink communications. Background Art

[0004] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcast, etc. These systems may be capable of supporting communication with multiple users by sharing available system resources (e.g., time, frequency, and power). A wireless multiple-access communication system may include multiple base stations (BSs), each of which simultaneously supports communication for multiple communication devices, which may be otherwise referred to as user equipment (UE).

[0005] In order to meet the growing demand for extended mobile broadband connectivity, wireless communication technology is evolving from LTE technology to next-generation new radio (NR) technology. For example, compared to LTE, NR is designed to provide lower latency, higher bandwidth or throughput, and higher reliability. NR is designed to operate on a wide spectrum band array, for example, from low frequency bands below about 1 gigahertz (GHz) and mid-frequency bands from about 1 GHz to about 6 GHz to high frequency bands such as millimeter wave (mmWave) bands. NR is also designed to operate across different spectrum types, from licensed spectrum to unlicensed spectrum and shared spectrum. Spectrum sharing enables operators to have the opportunity to aggregate spectrum to dynamically support high-bandwidth services. Spectrum sharing can extend the benefits of NR technology to operating entities that may not have access to licensed spectrum.

[0006] NR can support various deployment scenarios to benefit from various spectrums in different frequency ranges, licensed and / or unlicensed, and / or coexistence of LTE and NR technologies. For example, NR can be deployed in standalone NR mode on licensed and / or unlicensed bands, or in dual connectivity mode with various combinations of NR and LTE on licensed and / or unlicensed bands.

[0007] In a wireless communication network, a BS can communicate with a UE in both the uplink and downlink directions. Sidelinks were introduced in LTE to allow a UE to transmit data to another UE (e.g., from one vehicle to another vehicle) without tunneling through the BS and / or associated core network. LTE sidelink technology has been extended to provide device-to-device (D2D) communications, vehicle-to-everything (V2X) communications, and / or cellular vehicle-to-everything (C-V2X) communications. Similarly, NR can be extended to support sidelink communications, D2D communications, V2X communications, and / or C-V2X on licensed and / or unlicensed bands (e.g., shared bands). Summary of the invention

[0008] The following summarizes some aspects of the present disclosure to provide a basic understanding of the technology discussed. This summary is not an exhaustive overview of all the expected features of the present disclosure, and is neither intended to identify the key or important elements of all aspects of the present disclosure, nor to delineate the scope of any or all aspects of the present disclosure. The sole purpose of this summary is to present some concepts of one or more aspects of the present disclosure in a summarized form as a prelude to more specific embodiments presented later.

[0009] In one aspect of the present disclosure, a method of wireless communication performed by a first sidelink user equipment (UE) may include: performing a first listen-before-talk (LBT) procedure; and sending at least one of the following to a second sidelink UE based on the success of the first LBT procedure: a resource indicator indicating resources associated with sidelink communication, wherein the resources are indicated relative to when the LBT procedure is successful; or a channel occupancy time (COT) indicator associated with COT sharing.

[0010] In an additional aspect of the present disclosure, a method of wireless communication performed by a first sidelink user equipment (UE) may include: receiving from a second sidelink UE: a first resource indicator indicating resources associated with sidelink communication, wherein the resources are indicated relative to the beginning of a first channel occupancy time (COT); and a first COT indicator associated with COT sharing; performing a first listen-before-talk (LBT) procedure; and sending sidelink communication to a third sidelink UE during the COT based on success of the first LBT procedure and at least in part on the first resource indicator or the first COT indicator.

[0011] In an additional aspect of the present disclosure, a first sidelink user equipment (UE) may include: a memory; a transceiver; and at least one processor coupled to the memory and the transceiver, wherein the first sidelink UE is configured to: perform a first listen-before-talk (LBT) procedure; and send at least one of the following to a second sidelink UE based on the success of the first LBT procedure: a resource indicator indicating resources associated with sidelink communication, wherein the resources are indicated relative to when the first LBT procedure is successful; or a channel occupancy time (COT) indicator associated with COT sharing.

[0012] In an additional aspect of the present disclosure, a first sidelink user equipment (UE) may include: a memory; a transceiver; and at least one processor coupled to the memory and the transceiver, wherein the first sidelink UE is configured to receive from a second sidelink UE: a first resource indicator indicating resources associated with sidelink communication, wherein the resources are indicated relative to the beginning of a first channel occupancy time (COT); and a first COT indicator associated with COT sharing; perform a first listen-before-talk (LBT) procedure; and send sidelink communication to a third sidelink UE during the COT based on success of the first LBT procedure and at least in part on the first resource indicator or the first COT indicator.

[0013] After reading the description of the specific exemplary embodiments of the present invention below in conjunction with the accompanying drawings, other aspects, features and examples of the present invention will become apparent to those of ordinary skill in the art. Although the features of the present invention may be discussed below with respect to certain aspects and drawings, all examples of the present invention may include one or more of the advantageous features discussed herein. In other words, although one or more examples may be discussed as having certain advantageous features, one or more of such features may also be used according to the various examples of the present invention discussed herein. In a similar manner, although the exemplary aspects may be discussed below as device, system or method examples, it should be understood that such exemplary examples may be implemented in various devices, systems and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A wireless communication network according to some aspects of the present disclosure is illustrated.

[0015] Figure 2 An example disaggregated base station architecture is illustrated in accordance with some aspects of the present disclosure.

[0016] Figure 3 An example of a resource configuration supporting COT sharing in sidelink communications according to some aspects of the present disclosure is illustrated.

[0017] Figure 4 Examples of resource selection and indication to support COT sharing in sidelink communications according to some aspects of the present disclosure are illustrated.

[0018] Figure 5 Examples of resource selection and indication to support COT sharing in sidelink communications according to some aspects of the present disclosure are illustrated.

[0019] Figure 6 is a signaling diagram of a wireless communication method according to some aspects of the present disclosure.

[0020] Figure 7 is a block diagram of an exemplary user equipment (UE) according to some aspects of the present disclosure.

[0021] Figure 8 is a block diagram of an exemplary network element according to some aspects of the present disclosure.

[0022] Fig. 9 is a flow chart of a communication method according to some aspects of the present disclosure.

[0023] Fig.10 is a flow chart of a communication method according to some aspects of the present disclosure. DETAILED DESCRIPTION

[0024] The detailed description set forth below in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. In order to provide a comprehensive understanding of the various concepts, the detailed description includes specific details. However, it is apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, in order to avoid obscuring such concepts, well-known structures and components are shown in block diagram form.

[0025] The present disclosure as a whole relates to wireless communication systems, which are also referred to as wireless communication networks. In various instances, techniques and devices can be used for wireless communication networks, such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single carrier FDMA (SC-FDMA) networks, LTE networks, GSM networks, 5th generation (5G) or new radio (NR) networks, and other communication networks. As described herein, the terms "network" and "system" can be used interchangeably.

[0026] OFDMA network can realize radio technology such as Evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers (IEEE) 802.11, IEEE 802.16, IEEE 802.20, flash-OFDM, etc. UTRA, E-UTRA and Global System for Mobile Communications (GSM) are parts of Universal Mobile Telecommunications System (UMTS). Specifically, Long Term Evolution (LTE) is a version of UMTS using E-UTRA. UTRA, E-UTRA, GSM, UMTS and LTE are described in documents provided by an organization named "3rd Generation Partnership Project" (3GPP), and cdma2000 is described in documents from an organization named "3rd Generation Partnership Project 2" (3GPP2). These radio technologies and standards are known or under development. For example, the 3rd Generation Partnership Project (3GPP) is a collaboration between telecommunication association groups with the goal of defining a globally applicable third generation (3G) mobile phone specification. 3GPP Long Term Evolution (LTE) is a 3GPP project aimed at improving the Universal Mobile Telecommunications System (UMTS) mobile phone standard. 3GPP may define specifications for next generation mobile networks, mobile systems, and mobile devices. The present disclosure relates to the evolution from LTE, 4G, 5G, NR and beyond wireless technologies, where access to the wireless spectrum is shared between networks using a range of new and different radio access technologies or radio air interfaces.

[0027] Specifically, 5G networks consider various deployments, various spectrums, and various services and devices that can be implemented using a unified air interface based on OFDM. To achieve these goals, in addition to developing new radio technologies for 5G NR networks, further enhancements to LTE and LTE-A are also considered. 5G NR will be able to scale to (1) ultra-high density (e.g., about 1M nodes / km) 2 (1) provide coverage for the massive Internet of Things (IoT) with ultra-low complexity (e.g., on the order of tens of bits / second), ultra-low energy (e.g., on the order of 10+ years of battery life), and deep coverage with the ability to reach challenging locations; (2) provide coverage including mission-critical control with strong security to protect sensitive personal, financial, or classified information, ultra-high reliability (e.g., on the order of 99.9999% reliability), ultra-low latency (e.g., on the order of 1 millisecond), and for users with extensive mobility or lack of mobility; and (3) provide coverage with enhanced mobile broadband (including extremely high capacity (e.g., on the order of 10 Tbps / km 2 ), extremely high data rates (e.g., multi-Gbps rates, 100+Mbps user experience rates), and deep awareness coverage with advanced discovery and optimization.

[0028] 5G NR can be implemented using an optimized OFDM-based waveform with scalable parameter sets and transmission time intervals (TTIs); with a common, flexible framework to efficiently multiplex services and features using dynamic low-latency time division duplex (TDD) / frequency division duplex (FDD) designs; and with advanced wireless technologies such as massive multiple-input multiple-output (MIMO), robust millimeter wave (mmWave) transmission, advanced channel decoding, and device-centric mobility. The scalability of parameter sets in 5G NR and the scaling of subcarrier spacing can efficiently address various services operating across different spectrums and different deployments. For example, in various outdoor and macro coverage deployments of less than 3GHz FDD / TDD implementations, the subcarrier spacing may appear at 15kHz on bandwidths (BW) such as 5MHz, 10MHz, 20MHz, etc. For other various outdoor and small cell coverage deployments of TDD greater than 3GHz, the subcarrier spacing may appear at 30kHz on 80MHz / 100MHz BW. For various other indoor broadband implementations, using TDD on the unlicensed portion of the 5 GHz band, subcarrier spacing may occur at 60 kHz over 160 MHz BW. Finally, for various deployments transmitting with the mmWave component at 28 GHz TDD, subcarrier spacing may occur at 120 kHz over 500 MHz BW.

[0029] 5G NR's scalable parameter sets facilitate scalable TTIs for different latency and quality of service (QoS) requirements. For example, shorter TTIs can be used for low latency and high reliability, while longer TTIs can be used for higher spectral efficiency. Efficient multiplexing of long and short TTIs allows transmission to start on symbol boundaries. 5G NR also envisions a self-contained integrated subframe design with uplink / downlink scheduling information, data, and acknowledgment in the same subframe. The self-contained integrated subframe supports communications in unlicensed spectrum or contention-based shared spectrum, adaptive uplink / downlink, which can be flexibly configured on a per-cell basis to dynamically switch between uplink and downlink to meet current business needs.

[0030] The various other aspects and features of the present disclosure are further described below. It should be apparent that the teachings herein can be embodied in various forms, and any specific structure, function, or both disclosed herein are merely representative and not restrictive. Based on the teachings herein, it should be understood by those of ordinary skill in the art that the aspects disclosed herein can be implemented independently of any other aspects, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement a device or practice a method. In addition, such a device can be implemented or such a method can be practiced using other structures, functionality, or structures and functionality other than or different from one or more of the aspects set forth herein. For example, the method can be implemented as a part of a system, device, device, and / or as an instruction stored on a computer-readable medium for execution on a processor or computer. In addition, one aspect can include at least one element of a claim.

[0031] Deploying NR on unlicensed spectrum is called NR unlicensed (NR-U). The Federal Communications Commission (FCC) and the European Telecommunications Standards Institute (ETSI) are working to regulate 6 GHz as a new unlicensed band for wireless communications. The addition of the 6 GHz band allows hundreds of megahertz (MHz) of bandwidth (BW) to be used for unlicensed band communications. Additionally, NR-U can also be deployed on the 2.4 GHz unlicensed band, which is currently shared by various radio access technologies (RATs) such as IEEE 802.11 wireless local area networks (WLANs) or WiFi and / or license assisted access (LAA). Sidelink communications can benefit from utilizing the additional bandwidth available in unlicensed spectrum. However, channel access in a specific unlicensed spectrum can be managed by official agencies. For example, some unlicensed bands may impose restrictions on the power spectral density (PSD) and / or minimum occupied channel bandwidth (OCB) of transmissions in unlicensed bands. For example, the unlicensed national information infrastructure (UNII) radio band has a minimum OCB requirement of about at least 70%.

[0032] Some sidelink systems may operate on a 20 MHz bandwidth in an unlicensed band, e.g., for listen-before-talk (LBT) based channel access. The BS may configure a sidelink resource pool for sidelink communications on one or more 20 MHz LBT sub-bands. The sidelink resource pool is typically allocated with a plurality of frequency subchannels within a sidelink bandwidth part (SL-BWP), and the sidelink UE may select a sidelink resource (e.g., one or more subchannels in frequency and one or more time slots in time) for sidelink communications from the sidelink resource pool.

[0033] The deployment of a communication system (such as a 5G New Radio (NR) system) can be arranged with various components or constituent parts in a variety of ways. In a 5G NR system or network, a network node, a network entity, a mobility element of a network, a radio access network (RAN) node, a core network node, a network element or a network equipment (such as a base station (BS), or one or more units (or one or more components) that perform base station functionality can be implemented in an aggregated architecture or a decomposed architecture. For example, a BS (such as a Node B (NB), an evolved NB (eNB), an NR BS, a 5G NB, an access point (AP), a transmit receive point (TRP) or a cell, etc.) can be implemented as an aggregated base station (also referred to as an independent BS or a monolithic BS) or a decomposed base station.

[0034] A converged base station may be configured to utilize a radio protocol stack physically or logically integrated within a single RAN node. A decomposed base station may be configured to utilize a protocol stack physically or logically distributed between two or more units, such as one or more central or centralized units (CUs), one or more distributed units (DUs), or one or more radio units (RUs). In some aspects, a CU may be implemented within a RAN node, and one or more DUs may be co-located with the CU, or alternatively, may be geographically or virtually distributed in one or more other RAN nodes. A DU may be implemented to communicate with one or more RUs. Each of a CU, a DU, and a RU may also be implemented as a virtual unit, i.e., a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU).

[0035] Base station type operations or network designs may take into account the aggregated nature of base station functionality. For example, a disaggregated base station may be used in an integrated access and backhaul (IAB) network, an open radio access network (O-RAN (network configurations such as those initiated by the O-RAN Alliance)), or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN)). Decomposition may include distributing functionality across two or more units at various physical locations, as well as virtually distributing functionality of at least one unit, which may enable flexibility in network design. Individual units of a disaggregated base station or disaggregated RAN architecture may be configured for wired or wireless communication with at least one other unit.

[0036] Figure 1A wireless communication network 100 according to some aspects of the present disclosure is illustrated. The network 100 includes multiple base stations (BSs) 105 and other network entities. The BSs 105 may be stations that communicate with the UEs 115, and may also be referred to as evolved Node Bs (eNBs), next generation eNBs (gNBs), access points, etc. Each BS 105 may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" may refer to the particular geographic coverage area of ​​the BS 105 and / or the BS subsystem serving the coverage area, depending on the context in which the term is used.

[0037] BS105 may provide communication coverage for macro cells or small cells (such as pico cells or femto cells) and / or other types of cells. Macro cells generally cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscriptions with a network provider. Small cells (such as pico cells) will generally cover a relatively small geographic area and may allow unrestricted access by UEs with service subscriptions with a network provider. Small cells (such as femto cells) will generally also cover a relatively small geographic area (e.g., a home) and, in addition to unrestricted access, may also provide restricted access by UEs associated with the femto cells (e.g., UEs in a closed subscriber group (CSG), UEs of users in a home, etc.). A BS for a macro cell may be referred to as a macro BS. A BS for a small cell may be referred to as a small cell BS, a pico BS, a femto BS, or a home BS. In Figure 1 In the example shown, BS105d and 105e may be conventional macro BSs, while BS105a-105c may be macro BSs with one of three-dimensional (3D), full-dimensional (FD) or massive MIMO capabilities. BS105a-105c may utilize its higher-dimensional MIMO capabilities to employ 3D beamforming in both elevation and azimuth beamforming to increase coverage and capacity. BS105f may be a small cell BS, which may be a home node or a portable access point. BS105 may support one or more (e.g., two, three, four, etc.) cells.

[0038] Network 100 may support synchronous operation or asynchronous operation. For synchronous operation, the BSs may have similar frame timing, and transmissions from different BSs may be approximately aligned in time. For asynchronous operation, the BSs may have different frame timing, and transmissions from different BSs may not be aligned in time.

[0039] UE 115 is dispersed throughout the wireless network 100, and each UE 115 can be stationary or mobile. UE 115 may also be referred to as a terminal, a mobile station, a subscriber unit, a station, etc. UE 115 may be a cellular phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a wireless local loop (WLL) station, etc. In one aspect, UE 115 may be a device including a universal integrated circuit card (UICC). On the other hand, UE may be a device that does not include a UICC. In some aspects, UE 115 that does not include a UICC may also be referred to as an IoT device or an Internet of Everything (IoE) device. UE 115a-115d is an example of a mobile smart phone type device that accesses the network 100. UE 115 may also be a machine that is specifically configured for connected communications (including machine type communications (MTC), enhanced MTC (eMTC), narrowband IoT (NB-IoT), etc.). UE 115e-115h are examples of various machines configured for communication to access network 100. UE 115i-115k are examples of vehicles equipped with wireless communication devices configured for communication to access network 100. UE 115 may be able to communicate with any type of BS (whether macro BS, small cell, etc.). Figure 1 , a lightning symbol (e.g., a communication link) indicates wireless transmission between UE 115 and a serving BS 105 (which is a BS designated to provide service to UE 115 on a downlink (DL) and / or uplink (UL), desired transmission between BSs 105, backhaul transmission between BSs, or sidelink transmission between UE 115.

[0040] In operation, BSs 105a-105c use 3D beamforming and cooperative spatial techniques such as coordinated multipoint (CoMP) or multiple connections to serve UEs 115a and 115b. Macro BS 105d may perform backhaul communications with BSs 105a-105c and small cell BS 105f. Macro BS 105d may also transmit multicast services that UEs 115c and 115d subscribe to and receive. Such multicast services may include mobile TV or streaming video, or may include other services for providing community information, such as weather emergencies or alerts, such as Amber alerts or gray alerts.

[0041] BS 105 may also communicate with a core network. The core network may provide user authentication, access authorization, tracking, Internet Protocol (IP) connections, and other access, routing, or mobility functions. At least some BS 105 (e.g., the BS may be an example of an evolved Node B (eNB) or an access node controller (ANC)) may interface with the core network 130 via a backhaul link (e.g., S1, S2, etc.), and may perform radio configuration and scheduling to communicate with UE 115. In various examples, BS 105 may communicate with each other directly or indirectly (e.g., via a core network) via a backhaul link (e.g., X1, X2, etc.), which may be a wired communication link or a wireless communication link.

[0042] The network 100 may also support mission-critical communications with ultra-reliable and redundant links for mission-critical devices such as UE 115e, which may be a vehicle (e.g., a car, truck, bus, autonomous vehicle, airplane, ship, etc.). The redundant communication links with UE 115e may include links from macro BSs 105d and 105e, and a link from a small cell BS 105f. Other machine-type devices such as UE 115f (e.g., a thermometer), UE 115g (e.g., a smart meter), and UE 115h (e.g., a wearable device) may communicate directly with a BS (such as small cell BS 105f and macro BS 105e) through the network 100, or in a multi-hop configuration by communicating with another user device that relays its information to the network (such as UE 115f communicating temperature measurement information to smart meter UE 115g, which is then reported to the network through small cell BS 105f). In some aspects, the UE 115h may harvest energy from the surrounding environment associated with the UE 115h. The network 100 may also provide additional network efficiency through dynamic, low-latency TDD / FDD communications such as vehicle-to-vehicle (V2V) communications between the UE 115i, 115j, or 115k and other UEs 115, vehicle-to-everything (V2X) communications, cellular vehicle-to-everything (C-V2X) communications, and / or vehicle-to-infrastructure (V2I) communications between the UE 115i, 115j, or 115k and the BS 105.

[0043] In some implementations, the network 100 utilizes an OFDM-based waveform for communication. An OFDM-based system may divide the system BW into multiple (K) orthogonal subcarriers, which are also commonly referred to as subcarriers, tones, frequency bins, etc. Each subcarrier may be modulated with data. In some instances, the subcarrier spacing between adjacent subcarriers may be fixed, and the total number of subcarriers (K) may depend on the system BW. The system BW may also be divided into subbands. In other instances, the subcarrier spacing and / or the duration of the TTI may be scalable.

[0044] In some instances, BS105 may assign or schedule transmission resources (e.g., in the form of time-frequency resource blocks (RBs)) for downlink (DL) transmission and uplink (UL) transmission in network 100. DL refers to the transmission direction from BS105 to UE 115, and UL refers to the transmission direction from UE 115 to BS105. The communication may be in the form of a radio frame. The radio frame may be divided into a plurality of subframes, such as about 10. Each subframe may be divided into time slots, such as about 2. Each time slot may also be divided into micro-time slots. In FDD mode, simultaneous UL transmission and DL transmission may occur in different frequency bands. For example, each subframe includes a UL subframe in a UL frequency band and a DL subframe in a DL frequency band. In TDD mode, UL transmission and DL transmission occur in different time periods using the same frequency band. For example, a subframe subset (e.g., a DL subframe) in a radio frame may be used for DL ​​transmission, and another subframe subset (e.g., a UL subframe) in a radio frame may be used for UL transmission.

[0045] DL subframes and UL subframes may also be divided into several zones. For example, each DL subframe or UL subframe may have a predefined zone for the transmission of reference signals, control information, and data. Reference signals are predetermined signals that facilitate communication between BS105 and UE 115. For example, reference signals may have a specific pilot pattern or structure, wherein pilot tones may span an operational BW or frequency band, and each pilot tone is located at a predefined time and a predefined frequency. For example, BS105 may send a cell-specific reference signal (CRS) and / or a channel state information-reference signal (CSI-RS) to enable UE 115 to estimate a DL channel. Similarly, UE 115 may send a sounding reference signal (SRS) to enable BS105 to estimate an UL channel. Control information may include resource assignments and protocol control. Data may include protocol data and / or operational data. In some instances, BS105 and UE 115 may communicate using self-contained subframes. Self-contained subframes may include a portion for DL ​​communication and a portion for UL communication. A self-contained subframe may be DL-centric or UL-centric. A DL-centric subframe may include a DL communication duration that is longer than a UL communication duration. A UL-centric subframe may include a UL communication duration that is longer than a UL communication duration.

[0046] In some instances, network 100 may be an NR network deployed on a licensed spectrum. BS 105 may send synchronization signals (e.g., including a primary synchronization signal (PSS) and a secondary synchronization signal (SSS)) in network 100 to facilitate synchronization. BS 105 may broadcast system information associated with network 100 (e.g., including a master information block (MIB), remaining minimum system information (RMSI), and other system information (OSI)) to facilitate initial network access. In some instances, BS 105 may broadcast PSS, SSS, and / or MIB in the form of a synchronization signal block (SSB) on a physical broadcast channel (PBCH), and may broadcast RMSI and / or OSI on a physical downlink shared channel (PDSCH).

[0047] In some examples, a UE 115 attempting to access the network 100 may perform an initial cell search by detecting the PSS from the BS 105. The PSS may enable synchronization of period timing and may indicate a physical layer identification value. The UE 115 may then receive the SSS. The SSS may enable radio frame synchronization and may provide a cell identification value that may be combined with the physical layer identification value to identify the cell. The SSS may also enable detection of duplex mode and cyclic prefix length. The PSS and SSS may be located in the center portion of the carrier or at any suitable frequency within the carrier.

[0048] After receiving the PSS and SSS, the UE 115 may receive the MIB. The MIB may include system information for initial network access and scheduling information for RMSI and / or OSI. After decoding the MIB, the UE 115 may receive the RMSI and / or OSI. The RMSI and / or OSI may include radio resource control (RRC) information related to random access channel (RACH) procedures, paging, control resource set (CORESET) for physical downlink control channel (PDCCH) monitoring, physical uplink control channel (PUCCH), physical uplink shared channel (PUSCH), power control, SRS, and cell barring.

[0049] After obtaining the MIB, RMSI, and / or OSI, the UE 115 may perform a random access procedure to establish a connection with the BS 105. For the random access procedure, the UE 115 may send a random access preamble, and the BS 105 may respond with a random access response. Upon receiving the random access response, the UE 115 may send a connection request to the BS 105, and the BS 105 may respond with a connection response (e.g., a contention resolution message).

[0050] After establishing the connection, the UE 115 and the BS 105 may enter a normal operation phase in which operational data may be exchanged. For example, the BS 105 may schedule the UE 115 for UL communication and / or DL ​​communication. The BS 105 may send an UL scheduling grant and / or a DL scheduling grant to the UE 115 via the PDCCH. The BS 105 may send a DL communication signal to the UE 115 via the PDSCH according to the DL scheduling grant. The UE 115 may send an UL communication signal to the BS 105 via the PUSCH and / or the PUCCH according to the UL scheduling grant.

[0051] The network 100 may be designed to implement a wide range of use cases. Although in some examples, the network 100 may utilize a monolithic base station, there are a variety of other architectures that can be used to perform various aspects of the present disclosure. For example, BS105 may be separated into a remote radio head (RRH) and a baseband unit (BBU). The BBU may be concentrated in a BBU pool and connected to the RRH via a low latency and high bandwidth transmission link (such as an optical transmission link). The BBU pool may be a cloud-based resource. In some aspects, baseband processing is performed on a virtualized server running in a data center rather than being co-located with the BS105. In another example, base station functionality may be split between a remote unit (RU), a distributed unit (DU), and a central unit (CU). The RU typically performs low physical layer functions, while the DU performs higher layer functions, which may include higher physical layer functions. The CU performs higher RAN functions, such as radio resource control (RRC).

[0052] For simplicity of discussion, the present disclosure refers to the methods of the present disclosure being performed by a base station or more generally by a network entity, while the functionality may be performed by a variety of architectures other than a monolithic base station. In addition to a disaggregated base station, aspects of the present disclosure may also be performed by a centralized unit (CU), a distributed unit (DU), a radio unit (RU), a near real-time (near RT) RAN intelligent controller (RIC), a non-real-time (non-RT) RIC, an integrated access and backhaul (IAB) node, a relay node, a sidelink node, etc.

[0053] In some aspects, UE 115k may perform a first listen-before-talk (LBT) procedure. UE 115k may perform the first LBT procedure in an unlicensed band. UE 115k may send, based on the success of the first LBT procedure, at least one of: a resource indicator indicating resources associated with sidelink communications, wherein the resources are indicated relative to when the LBT procedure was successful; or a channel occupancy time (COT) indicator associated with COT sharing. UE 115k may send the resource indicator and / or the COT indicator to UE 115j in the same communication as the PSSCH (e.g., the same time slot). The PSSCH may carry one or more transport blocks.

[0054] Figure 2 A diagram illustrating an example decomposed base station 200 architecture is shown. The decomposed base station 200 architecture may include one or more central units (CUs) 210 that may communicate directly with a core network 220 via a backhaul link, or indirectly with the core network 220 through one or more decomposed base station units, such as a near real-time (near-RT) RAN intelligent controller (RIC) 225 via an E2 link, or a non-real-time (non-RT) RIC 215 associated with a service management and orchestration (SMO) framework 205, or both. The CU 210 may communicate with one or more distributed units (DUs) 230 via respective midhaul links, such as an F1 interface. The DU 230 may communicate with one or more radio units (RUs) 240 via respective fronthaul links. The RU 240 may communicate with respective UEs 120 via one or more radio frequency (RF) access links. In some implementations, a UE 120 may be served simultaneously by multiple RUs 240.

[0055] Each of these units (i.e., CU 210, DU 230, RU 240, near-RT RIC 225, non-RT RIC 215, and SMO framework 205) may include one or more interfaces or be coupled to one or more interfaces, which are configured to receive or send signals, data, or information (collectively referred to as signals) via a wired transmission medium or a wireless transmission medium. Each of these units or an associated processor or controller that provides instructions to the communication interface of these units may be configured to communicate with one or more of the other units via a transmission medium. For example, these units may include a wired interface that is configured to receive or send signals to one or more of the other units via a wired transmission medium. Additionally, these units may include a wireless interface that may include a receiver, a transmitter, or a transceiver (such as a radio frequency (RF) transceiver) that is configured to receive or send signals, or both, to one or more of the other units on a wireless transmission medium.

[0056] In some aspects, CU 210 may host one or more higher layer control functions. Such control functions may include radio resource control (RRC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), etc. Each control function may be implemented using an interface that is configured to communicate signals with other control functions hosted by CU 210. CU210 may be configured to handle user plane functionality (i.e., central unit-user plane (CU-UP)), control plane functionality (i.e., central unit-control plane (CU-CP)), or a combination thereof. In some specific implementations, CU 210 may be logically split into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP unit may communicate bidirectionally with the CU-CP unit via an interface (such as an E1 interface). As needed, CU 210 may be implemented to communicate with DU 230 for network control and signaling.

[0057] DU 230 may correspond to a logical unit that includes one or more base station functions for controlling the operation of one or more RUs 240. In some aspects, DU 230 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, etc.) depending at least in part on a functional split, such as a functional split defined by the 3rd Generation Partnership Project (3GPP). In some aspects, DU 230 may further host one or more low PHY layers. Each layer (or module) may be implemented using an interface that is configured to communicate signals with other layers (and modules) hosted by DU 230 or with control functions hosted by CU 210.

[0058] The lower layer functionality may be implemented by one or more RUs 240. In some deployments, the RU 240 controlled by the DU 230 may correspond to a logical node that hosts RF processing functions or low PHY layer functions (such as performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, etc.), or both, based at least in part on functional splitting (such as lower layer functional splitting). In such an architecture, the RU 240 may be implemented to handle over-the-air (OTA) communications with one or more UEs 120. In some specific implementations, real-time and non-real-time aspects of control plane communications and user plane communications with the RU 240 may be controlled by the corresponding DU 230. In some scenarios, this configuration may enable the DU 230 and the CU 210 to be implemented in a cloud-based RAN architecture (such as a vRAN architecture).

[0059] The SMO framework 205 may be configured to support RAN deployment and provisioning of non-virtualized network elements and virtualized network elements. For non-virtualized network elements, the SMO framework 205 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements, which may be managed via an operation and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO framework 205 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 290) to perform network element lifecycle management (such as instantiating virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements may include, but are not limited to, CU 210, DU 230, RU 240, and near-RT RIC 225. In some specific implementations, the SMO framework 205 may communicate with hardware aspects of the 4G RAN (such as an open eNB (O-eNB) 211) via the O1 interface. Additionally, in some specific implementations, the SMO framework 205 may communicate directly with one or more RUs 240 via the O1 interface. The SMO framework 205 may also include a non-RT RIC 215 configured to support the functionality of the SMO framework 205 .

[0060] The non-RT RIC 215 may be configured to include logic functions that enable non-real-time control and optimization of RAN elements and resources, artificial intelligence / machine learning (AI / ML) workflows including model training and updating, or policy-based guidance of applications / features in the near-RT RIC 225. The non-RT RIC 215 may be coupled to or in communication with the near-RT RIC 225 (such as via an A1 interface). The near-RT RIC 225 may be configured to include logic functions that enable near-real-time control and optimization of RAN elements and resources via data collection and actions through an interface (such as via an E2 interface) that connects one or more CUs 210, one or more DUs 230, or both, and the O-eNB with the near-RT RIC 225.

[0061] In some implementations, in order to generate an AI / ML model to be deployed in the near-RT RIC 225, the non-RT RIC 215 may receive parameters or external enrichment information from an external server. Such information may be utilized by the near-RT RIC 225 and may be received from a non-network data source or from a network function at the SMO framework 205 or the non-RT RIC 215. In some examples, the non-RT RIC 215 or the near-RT RIC 225 may be configured to tune RAN behavior or performance. For example, the non-RT RIC 215 may monitor long-term trends and patterns of performance and employ AI / ML models to perform corrective actions through the SMO framework 205 (such as via reconfiguration of O1) or via the creation of RAN management policies (such as A1 policies).

[0062] In some aspects, the first UE 120 may perform a first listen-before-talk (LBT) procedure. The first UE 120 may perform the first LBT procedure in an unlicensed band. The first UE 120 may send at least one of the following to the second UE 120 based on the success of the first LBT procedure: a resource indicator indicating resources associated with sidelink communication, wherein the resources are indicated relative to when the LBT procedure is successful; or a channel occupancy time (COT) indicator associated with COT sharing. The first UE 120 may send the resource indicator and / or the COT indicator to the second UE 120 in the same communication as the PSSCH (e.g., the same time slot). The PSSCH may carry one or more transport blocks.

[0063] Figure 3 An example of resource selection and indication 300 for supporting COT sharing in sidelink communications according to some aspects of the present disclosure is illustrated. Resource configuration 300 may be implemented by aspects of wireless communication network 100 and / or wireless communication network 200. For example, resource configuration 300 may be implemented by one or more UEs (e.g., UE 115, UE 120, or UE 700) to conduct sidelink communications, such as described by wireless communication networks 100 and / or 200. Figure 3 , the x-axis represents time in some arbitrary units.

[0064] In some aspects, the sidelink UE may operate in resource allocation mode 2, in which the medium access control (MAC) layer of the sidelink UE (e.g., the transmitting UE) may select resources for the initial transmission in time slot i, the first retransmission in time slot j, and the second retransmission in time slot k. The sidelink resource selection at the MAC layer may indicate to the physical layer the resources for the initial transmission in time slot i and the reserved resources (e.g., 2 reserved resource sets) in time slot j and time slot k for future transmissions (e.g., retransmissions in the event that the initial transmission in time slot i fails (e.g., HARQ NACK is sent to the transmitting UE in PSFCH314)). The UE (e.g., the physical layer of the UE) may send an indication of the reserved resources to other sidelink UEs. The sidelink transmitting UE may send an indication of the reserved resources to the sidelink UEs that intend to share the COT with the sidelink transmitting UE. The UE may send an indication of reserved resources (e.g., reserved resources in slot j and slot k for transmission or retransmission) to other sidelink UEs via an SCI (e.g., SCI-1 and / or SCI-2). In some aspects, the UE may send an indicator of reserved resources for future transmissions or retransmissions in the SCI of slot i (e.g., sent with the initial transmission). Subsequently, the UE may send the reserved resources for two future transmissions or retransmissions in the SCI of slot j. Subsequently, the UE may send the selected resources for two future transmissions or retransmissions in the SCI of slot k, etc. The sending of reserved resource indicators may continue in this cascaded manner. Sidelink UEs that receive indicators of reserved resources may avoid sending in those reserved resources to allow the sidelink UEs that sent the indicator to send sidelink communications in the reserved resources.

[0065] Figure 4 An example of resource selection and indication 400 for supporting COT sharing in sidelink communications according to some aspects of the present disclosure is illustrated. Resource selection and indication 400 may be implemented by aspects of wireless communication network 100 and / or wireless communication network 200. For example, resource configuration 400 may be implemented by one or more UEs (e.g., UE 115, UE 120, or UE 700) to perform sidelink communications, such as described by wireless communication networks 100 and / or 200. Figure 4 , the x-axis represents time in some arbitrary units.

[0066] In some aspects, a first side link UE (e.g., UE 115, UE 120, or UE 700) may perform a listen-before-talk (LBT) procedure. The first side link UE may perform an LBT procedure or other clear channel assessment (CCA) on one or more side link communication channels. In some instances, the first side link UE may perform an LBT procedure or other CCA to obtain access to a channel occupancy time (COT) in an unlicensed (e.g., shared) spectrum. For example, the first side link UE may perform category 2 LBT, category 3 LBT, and / or category 4 LBT to obtain access to the COT. In some aspects, the first side link UE may perform LBT in one or more time resources, space resources, and / or frequency resources. These frequency resources may include spectrum, frequency band, frequency subband, frequency subchannel, resource element, resource block, and / or frequency interleaving. These time resources may include time slots, subslots (e.g., microslots), symbols, subframes, or any other suitable time resources. In some aspects, the first side link UE may perform LBT for all directions (e.g., using an omnidirectional antenna). In some aspects, the first sidelink UE may perform LBT for one or more directions (e.g., using a directional antenna having a beam in the direction of a UE to which the first sidelink UE intends to send communications and / or receive communications from).

[0067] In some aspects, the first sidelink UE may send a resource indicator indicating resources reserved for sidelink communication and / or a first channel occupancy time (COT) indicator for sharing COT. In this regard, the first sidelink UE (e.g., a transmitting UE) may send the resource indicator and / or the COT indicator via the SCI 312 or the MAC CE on the PSSCH 310, respectively. In some aspects, the first sidelink UE may send the resource indicator and / or the COT indicator to the receiving sidelink UE with which the first sidelink UE intends to communicate. Additionally or alternatively, as described below with reference to Figure 5 As described, the first side link UE may send a resource indicator and / or a COT indicator to other side link UEs with which the first side link UE intends to share a COT. For example, the first side link UE may intend to share a COT with other side link UEs near the first side link UE. In some aspects, the first side link UE may send a resource indicator and / or a COT indicator based on the success of the first LBT procedure.

[0068] In some aspects, the resource indicator sent by the first side link UE may indicate resources associated with the side link communication relative to when the LBT procedure (e.g., the first LBT, the second LBT, etc.) is successful. For example, if the first side link UE performs a successful LBT at time slot i, the resource indicator may indicate resources associated with the side link communication relative to time slot i. In some instances, the resource indicator may indicate resources associated with the side link communication as a number (e.g., an integer number) of time slots, a number of sub-time slots, or a number of symbols starting from time slot i (e.g., the end of time slot i and / or the beginning of time slot i). In some aspects, the resource indicator may indicate resources associated with the side link communication as a time value (e.g., a number of milliseconds) relative to time slot i.

[0069] In some aspects, the COT indicator sent by the first sidelink UE may indicate a COT identifier (ID), the start of the COT, and / or the duration of the COT. In some aspects, the sidelink UE may receive one or more COT indicators from other sidelink UEs (including the first sidelink UE), indicating multiple COT identifiers. The COT identifier may identify one or more COTs that the first sidelink UE may initiate and share with the sidelink UE. The first sidelink UE may send a COT identifier to a sidelink receiver UE (e.g., a second sidelink UE that shares a COT for HARQ feedback on the PSFCH or a COT for a data packet or MAC CE on the PSSCH) and a UE sharing a COT (e.g., a third sidelink UE, a fourth sidelink UE, etc.) via an SCI 312 or MAC CE on the PSSCH 310 associated with the first transmission with a successful LBT. The COT identifier may identify a COT that may be shared between sidelink UEs that are near each other.

[0070] In some aspects, a location associated with a first side link UE (e.g., a zone identifier, a beam coverage pattern, a cell sector, a latitude / longitude range, a geo-fence, etc.) may be used to determine various aspects of COT sharing for the first side link UE and one or more of the other UEs sharing the COT. In some aspects, the first side link UE may determine its location based on a positioning procedure, GPS coordinates, radio frequency triangulation, or other suitable methods. Additionally or alternatively, the first side link UE may determine its location based on a zone identifier associated with the first side link UE. In this regard, the first UE may determine its zone identifier based on Section 5.8.11 of 3GPPTS 38.331 or other standard specifications related to zone identifiers. In some aspects, the third UE may determine whether to share the COT based at least in part on the distance from the first UE (e.g., based on the location of the first UE indicated in the SCI or MACCE associated with the first COT indicator and the location of the third UE itself). For example, if the distance is within the communication range configured or indicated by the first UE in the SCI or MAC CE associated with the first COT indicator, the UE may decide to share the COT. For another example, if the distance exceeds the communication range configured or indicated by the first UE in the SCI or MAC CE associated with the first COT indicator, the UE may decide not to share the COT.

[0071] In some aspects, the starting point of the COT (e.g., starting time slot, starting sub-time slot and / or starting symbol) may be based on the first side link UE performing a successful LBT. For example, the first side link UE may have resources selected by the MAC layer for initial transmission in time slot (i) and time slot (i+1). These resources may be resource sets of a resource pool. The resource sets may each include a number of time slots (e.g., consecutive time slots), a number of sub-time slots (e.g., consecutive sub-time slots), and / or a number of symbols (e.g., consecutive symbols).

[0072] In some aspects, the first sidelink UE may perform LBT prior to time slot (i) to gain access to the channel during time slot (i) and initiate COT. If LBT for accessing time slot (i) is unsuccessful, such as Figure 4As shown, the first side link UE may wait for a period of time (e.g., a backoff period) to perform another LBT at an offset from the next time slot boundary between time slot (i) and time slot (i+1). If the subsequent LBT is successful, the first side link UE may obtain access to the channel and initiate a COT starting at time slot (i+1). When the LBT is successful, the first side link UE may send a resource indicator and / or a COT indicator to the receiving side link UE and other UEs sharing the COT. For example, if the LBT is successful for the initial transmission at time slot (i+1), the COT indicator may indicate that the COT starts at time slot (i+1) (e.g., implicitly indicated by a first COT indicator in an SCI or MAC CE associated with the first transmission initiating the COT, or explicitly indicated by a second COT indicator in an SCI or MAC CE associated with a transmission of a shared COT performed by the first UE, the receiving UE, or other UEs sharing the COT after the first COT indicator). The receiving side link UE will monitor the initial PSSCH 310 in time slot (i+1).

[0073] The resource allocation sent by the first side link UE may indicate reserved resources that the first side link UE can use to send and / or resend side link communications. In some instances, the resource allocation may indicate the time resources (e.g., time slots, sub-time slots, and / or symbols) that the first side link UE is to send relative to when the first side link UE performs a successful LBT for an initial transmission at time slot (i+1). In some aspects, the first side link UE may select one or more resource sets (e.g., several consecutive time slots). For example, the first side link UE may select a first resource set m1 allocated for initial side link transmission, a second resource set m2 allocated for transmission or retransmission, and a third resource set ml (l>2) allocated for transmission or retransmission. The second resource set m2 may be indicated as x time slots after the first resource set m1 (e.g., the first resource of the resource set m2 is x time slots after the first resource of the resource set m1, the second resource of the resource set m2 is x time slots after the second resource of the resource set m1, and so on). The third resource set ml may be indicated as y time slots after the first resource set ml (e.g., the first resource of the resource set ml is y time slots after the first resource of the resource set ml, the second resource of the resource set ml is y time slots after the second resource of the resource set ml, etc.). In some aspects, x may be the same as or different from y. In some aspects, y may be greater than x.

[0074] In some aspects, the time interval (e.g., x time slots) between the first resource in the first resource set m1 and the first resource in the second resource set m2 may be based at least in part on: the resource configuration for the PSFCH in the resource pool and the time required for the side link receiving UE to process the initial PSSCH 310 and generate / send the associated HARQ feedback in the PSFCH 314, and / or the time required for the first side link UE to receive and process the HARQ feedback in the PSFCH 314 and generate / send a retransmission (e.g., based on the HARQ feedback being a NACK) in the reserved PSSCH 316. Similarly, the resource configuration for the PSFCH in the resource pool and the time interval (e.g., y time slots) between the first resource in the first resource set m1 and the first resource in the third resource set ml may be based on: the time required for the receiving sidelink UE to process the received transmission and generate / send the associated HARQ feedback, and / or the time required for the first sidelink UE to receive and process the HARQ feedback and generate / send a second retransmission (e.g., based on the HARQ feedback being a second NACK) in the reserved PSSCH 316. The sidelink UE receiving the transmission from the first sidelink UE may send HARQ feedback to the first sidelink UE in the PSFCH 314 relative to the transmission made by the first sidelink UE. For example, if the first side link UE performs a successful LBT just before time slot (i+1) and sends communication in time slot (i+1), the receiving side link UE may send HARQ feedback in time slot (i+1+n) and the first UE may monitor HARQ feedback in time slot (i+1+n), where n is the number of time slots relative to the transmission in time slot (i+1).

[0075] The first sidelink UE may send a sidelink communication (e.g., one or more transport blocks) to the receiving sidelink UE during the COT based on the LBT procedure success for the transmission at time slot (i+1). In this regard, the first sidelink UE may send a sidelink communication (e.g., based on the first retransmission of the received NACK) to the receiving sidelink UE in the indicated resources relative to time slot (i+1) (e.g., x time slots after the initial transmission in time slot i+1), and the receiving UE may monitor the sidelink communication sent to the receiving sidelink UE in the indicated resources relative to time slot (i+1) (e.g., x time slots after the initial transmission in time slot i+1).

[0076] Figure 5An example of resource selection and indication 500 for supporting COT sharing in sidelink communications according to some aspects of the present disclosure is illustrated. Resource selection and indication 500 may be implemented by aspects of wireless communication network 100 and / or wireless communication network 200. For example, resource selection and indication 500 may be implemented by one or more UEs (e.g., UE 115, UE 120, or UE 700) to conduct sidelink communications, such as described by wireless communication networks 100 and / or 200. Figure 5 , the x-axis represents time in some arbitrary units.

[0077] In some aspects, sidelink UE 115(1) may send a resource indicator indicating resources associated with sidelink communication and / or a first channel occupancy time (COT) indicator for COT sharing to other sidelink UEs. Figure 5 As shown, sidelink UE 115(1) may send a resource indicator and / or a first COT indicator to UE 115(2) and UE 115(3) so that UE 115(1), UE 115(2), and UE 115(3) share COT 520. For example, UE 115(1) may share COT with UE 115(2) and UE 115(3) that are near UE 115(1). In some aspects, UE 115(1) may send the resource indicator and / or the first COT indicator based on the LBT procedure success. UE 115(1) (e.g., a transmitting sidelink UE) may send the resource indicator and / or the first COT indicator to UE 115(2) and UE 115(3) via SCI 312 or MAC CE on PSSCH 310. In some aspects, the first sidelink UE may also send a resource indicator and / or a first COT indicator to a receiving sidelink UE with which UE 115(1) intends to communicate (e.g., a receiving sidelink UE), as described above with reference to Figure 4 In some aspects, the first sidelink UE may also send a resource indicator and / or a first COT indicator to a receiving sidelink UE with which UE 115(1) intends to communicate, such as a data packet and / or a MAC CE carried on a PSSCH from UE 115(2) to UE 115(1).

[0078] In some aspects, a first COT indicator sent by UE 115(1) may indicate a COT duration associated with a COT ID. The COT duration may indicate a time period during which sidelink UEs share COT 520, in which UE 115(1), UE 115(2), and UE 115(3) may transmit. The COT duration may begin with a first transmission with a successful LBT by UE 115(1). In some aspects, the COT duration may be based on the amount of data (e.g., transport blocks) that UE 115(1), UE 115(2), and / or UE 115(3) intends to transmit (e.g., based on a QoS profile of a sidelink communication in which nearby UEs participate). A larger amount of data may require a longer COT duration than a smaller amount of data. The COT duration may be indicated to the UEs sharing the COT as a number of slots, a number of subslots, a number of symbols, a number of milliseconds, or a combination thereof. In some aspects, the COT duration may indicate a remaining COT duration. For example, the COT duration may be a duration of e time slots. UE 115(1) may use f of the e time slots to send sidelink communications. The remaining COT duration may be indicated to the receiving sidelink UE and / or other sidelink UEs sharing the COT as ef time slots.

[0079] In some aspects, the COT duration may be indicated as a COT extension. UE 115(1) may initially indicate the COT duration as e slots in a first COT indicator in an SCI or MAC CE associated with a first transmission having a successful LBT for accessing a channel. UE 115(1) or a recipient UE of UE 115(1) or another UE 115 may subsequently extend the COT 520 in a second COT indicator in an SCI or MAC CE associated with a transmission sharing the COT (e.g., after the first transmission initiated the COT) by indicating the COT duration as e+g slots, where g represents the COT extension. For example, UE 115(1) may indicate the COT extension in a subsequent transmission (e.g., a second transmission, a third transmission, or other subsequent transmissions) as e+g slots. In some aspects, the COT 520 may be extended based on a failed transmission (e.g., UE 115(1) receiving a NACK from a receiving sidelink UE in PSFCH 314) requiring a retransmission. In some aspects, the COT 520 may be extended based on the number of UEs in the vicinity that share the COT. In some aspects, UE 115(1) may also include in the COT indicator whether extension to the COT associated with the COT ID is allowed.

[0080] In some aspects, the resource indicator sent by UE 115(1) may indicate resources associated with the sidelink communication relative to when the LBT procedure was successful. For example, if UE 115(1) performs a successful LBT for a transmission at time slot i, the resource indicator may indicate resources associated with the sidelink communication relative to time slot i. In some instances, the resource indicator may indicate resources associated with the sidelink communication as a number (e.g., an integer number) of time slots, a number of sub-time slots, or a number of symbols starting from time slot i (e.g., the end of time slot i and / or the beginning of time slot i). In some aspects, the resource indicator may indicate resources associated with the sidelink communication as a time value (e.g., a number of milliseconds) relative to time slot i.

[0081] In some aspects, a first COT indicator sent by UE 115(1) may indicate a COT identifier (ID), the start of COT 520 (e.g., implicitly indicated by a first COT indicator in an SCI or MAC CE associated with a first transmission initiating a COT, or explicitly indicated by a second COT indicator in an SCI or MAC CE associated with a transmission of a shared COT subsequent to the first COT indicator by the first UE, a receiving UE, or another UE sharing the COT), and / or a COT duration or COT end point. In some aspects, a sidelink UE may receive one or more COT indicators from other sidelink UEs, including UE 115(1), indicating multiple COT identifiers. The COT identifiers may identify one or more COTs that UE 115(1) may initiate and share with UEs, such as UE 115(2) and UE 115(3), as well as receiving UEs of UE 115(1). After successful LBT for the first transmission, UE 115(1) may send a COT identifier to UEs sharing the COT (e.g., UE 115(2) and UE 115(3) and a receiving UE of UE 115(1)) via SCI 312 or MAC CE on PSSCH 310. The COT identifier may identify a COT 520 that may be shared between sidelink UEs in proximity to each other.

[0082] In some aspects, locations (e.g., region identification, beam coverage pattern, cell sector, latitude / longitude range, geo-fence, etc.) associated with UE 115(1), UE 115(2), UE 115(3), and a receiving UE of UE 115(1) may be used to determine aspects of COT sharing for UE 115(1), UE 115(2), UE 115(3), and a receiving UE of UE 115(1), as described with reference to Figure 4 Described in detail.

[0083] In some aspects, the COT may be shared for a pair of source ID and destination ID (e.g., associated with a unicast or PC5 connection, e.g., between a transmitting UE and a receiving UE) as indicated in an SCI (e.g., L1 source ID and L1 destination ID) or a MAC CE (L1 source ID and destination ID and / or L2 source ID and destination ID) associated with a first COT indicator sent by UE 115(1). In some aspects, the COT may be shared for a destination ID (e.g., associated with a groupcast or broadcast) as indicated in an SCI (e.g., L1 destination ID) or a MAC CE (L1 destination ID and / or L2 destination ID) associated with a first COT indicator sent by UE 115(1). In some aspects, if enabled by pre-configuration or configuration or by an indication in a first COT indicator sent by UE 115(1), the COT may be shared for different source ID and destination ID pairs (e.g., for different unicasts) or different destination IDs (e.g., for different multicasts or broadcasts) compared to the pair of source ID and destination ID associated with the first COT indicator sent by UE 115(1) or the destination ID indicated in the SCI (e.g., L1 source ID and destination ID pair or L1 destination ID) or MACCE (L1 source ID and destination ID pair and / or L2 source ID and destination ID pair, or L1 destination ID and / or L2 destination ID).

[0084] In some aspects, UE 115(1) may perform LBT (e.g., Category 2 LBT, Category 3 LBT, and / or Category 4 LBT) prior to time slot (i) to gain access to the channel and initiate COT during time slot (i). If LBT at time slot (i) is unsuccessful, such as Figure 5As shown, UE 115(1) may wait for a period of time (e.g., a backoff period) to perform another LBT at an offset from the next slot boundary between slot (i) and slot (i+1). If the subsequent LBT is successful, UE 115(1) may acquire the channel and initiate a COT starting at slot (i+1). When the LBT is successful, UE 115(1) may send a resource indicator and / or a COT indicator to UE 115(2) and / or UE 115(3) and / or a receiving UE of UE 115(1). For example, if LBT is successful for the initial transmission at time slot (i+1), the COT indicator may indicate that the COT starts at time slot (i+1) (e.g., implicitly indicated by a first COT indicator in the SCI or MAC CE associated with the first transmission initiating the COT, or explicitly indicated by a second COT indicator in the SCI or MAC CE associated with a transmission of the shared COT performed by the first UE, the receiving UE, or other UEs sharing the COT after the first COT indicator).

[0085] The resource allocation sent by UE 115(1) may indicate reserved resources that UE 115(1) may use to send and / or resend sidelink communications. In some instances, the resource allocation may indicate the time resources (e.g., time slots, subslots, and / or symbols) that UE 115(1) is to send relative to when UE 115(1) performs a successful LBT for a first transmission at time slot (i+1). In some aspects, a first sidelink UE may be allocated one or more resource sets (e.g., a number of consecutive time slots). For example, UE 115(1) may have a first resource set m1 allocated for an initial sidelink transmission, a second resource set m2 allocated for a transmission or retransmission, and a third resource set ml allocated for a transmission or retransmission. The second resource set m2 may be indicated as x time slots after the first resource set m1. The third resource set ml may be indicated as y time slots after the first resource set m1. In some aspects, x may be the same as or different from y. In some aspects, y may be greater than x. Similarly, UE 115(2) may have a first resource set p1 allocated for initial sidelink transmission, a second resource set p2 allocated for transmission or retransmission, and a third resource set p1 (l>2) allocated for transmission or retransmission. In order to share the COT (e.g., to continue the COT with seamless transmission from UEs sharing the COT), the selection of resources p1, p2, and p1 may be based on resources used by UE 115(1) (e.g., m1) or reserved resources (e.g., resources m2 and / or resources ml), for example, the first resource in resource set p1 for transmitting Tx21 (e.g., in which one TB is transmitted) is based on the transmission Tx11 from UE 115(1), the first resource in resource set p2 for transmitting Tx22 is based on the transmission Tx12 from UE 115(1), and the first resource in resource set p1 for transmitting Tx21 is based on the transmission Tx11 from UE 115(1). Since at least resource m2 and resource ml are related to the start of COT 520 when UE 115(1) performs a successful LBT for the first transmission initiating the COT, resources p1, p2, and p1 may be indicated relative to the start of COT 520 when UE 115(1) performs a successful LBT for the first transmission initiating the COT. Similarly, UE 115(3) may have a first resource set q1 allocated for an initial sidelink transmission, a second resource set q2 allocated for a transmission or retransmission, and so on.In order to share the COT (e.g., to continue the COT with seamless transmissions from UEs sharing the COT), selection of resources q1 and q2 may be based on resources used by UE 115(1) and 115(2) (e.g., resource m1 and / or resource p1) or reserved resources (e.g., resource m2 and / or resource p2), respectively, for example, the first resource in resource set q1 for sending Tx31 (e.g., where more than one TB is sent) is based on the transmission of Tx11 from UE 115(1) and the transmission of Tx21 from UE 115(2), and the first resource in resource set p2 for sending Tx32 is based on the transmission of Tx12 from UE 115(1) and the transmission of Tx22 from UE 115(2). Since at least resource m2 and resource p2 are related to the start of COT 520 when UE 115(1) performs a successful LBT for the first transmission initiating the COT, resources q1 and q2 may be indicated relative to the start of COT 520 when UE 115(1) performs a successful LBT for the first transmission initiating the COT. The amount of resources (e.g., number of time slots) allocated for resources m1, m2, ml, p1, p2, p1, q1, and q2 may be based on the amount of TBs to be transmitted or retransmitted by the corresponding UE. For example, based on a QoS profile associated with one or more sidelink communications sharing the COT.

[0086] UE 115(1) may transmit sidelink communications (e.g., one or more transport blocks) to the receiving sidelink UE during COT 520 based on the successful LBT procedure for the first transmission at time slot (i+1). In this regard, UE 115(1) may transmit sidelink communications to the receiving sidelink UE in the indicated resources relative to time slot (i+1) (e.g., transmission Tx12 in time slot j+1 and / or transmission Tx11 in time slot k+1).

[0087] Figure 6 6 is a signaling diagram of a wireless communication method 600 according to some aspects of the present disclosure. The actions of the communication method 600 may be performed by a computing device (e.g., a processor, a processing circuit, and / or other suitable components) of a communication device or other suitable means for performing the actions. For example, a wireless communication device (such as UE 115, UE 120, or UE 700) may utilize one or more components (such as a processor 702, a memory 704, a COT sharing module 708, a transceiver 710, a modem 712, and one or more antennas 716) to perform various aspects of the method 600.

[0088] At action 602, UE 115a may determine resources for initiating a COT and subsequently sharing sidelink communications of the COT. For example, UE 115a may separately determine a set of resources for an initial transmission and / or a set of resources for (re)transmission (e.g., consecutive time slots or non-consecutive time slots). UE 115a may intend to transmit a sidelink communication (e.g., one or more TBs) to UE 115b. UE 115a may determine resources (e.g., a number of time slots) for the initial transmission and for a potential retransmission with a TB or for a potential transmission with a different TB. In some aspects, the MAC layer of UE 115a may select a first set of resources (e.g., reference 1 to the first resource set). Figure 5 m1 resource) for the first transmission to start COT, and select a second resource set and / or a third resource set (e.g., reference Figure 5 The m2 resources and / or ml resources) are used as a reserved resource set with reference to the first transmission or COT starting point for transmission or retransmission within the COT.

[0089] At action 604, the physical layer of the UE 115a may perform LBT (e.g., CAT 4 LBT) for the first transmission to transmit the first resource in the first resource set selected by the MAC layer of the UE 115a (e.g., reference Figure 5 If LBT is unsuccessful, the physical layer of UE 115a may wait for a period of time (e.g., one time slot period) and proceed to action 606 for the first transmission to transmit the first resource in the second resource set (e.g., reference 1) selected by the MAC layer of UE 115a. Figure 5 COT starts at time slot i+1).

[0090] At action 606, the physical layer of UE 115a may perform a successful LBT procedure or other clear channel assessment (CCA) on one or more sidelink communication channels. UE 115a may perform an LBT procedure or other CCA to obtain access to a channel in an unlicensed (e.g., shared) spectrum and initiate a COT. For example, UE 115a may perform full LBT (e.g., CAT 4 LBT) to obtain access to a channel in an unlicensed spectrum and initiate a COT. In some aspects, UE 115a may perform LBT in one or more LBT subbands (e.g., 20 MHz for LBT). One or more LBT subbands may include subchannels and / or resource blocks (RBs). In some aspects, UE 115a may perform LBT for one or more directional beams (e.g., beams in the direction of UE 115b to which UE 115a intends to send communications). The starting point of COT may be based on UE 115a performing a first successful LBT for a first transmission.

[0091] At action 608, UE 115a may receive a PSSCH (eg, reference Figure 5 A first transmission with one or more TBs is sent on a PSSCH 310 of the embodiment of the present invention, wherein the SCI or MAC CE includes at least one TB for reserving resources (e.g., reference Figure 5 m2 resources and / or references Figure 5 115a) and a first COT indicator indicating the resources that UE 115a intends to use for transmitting to UE 115b (e.g., a COT indicator initiating a COT to UE 115b). When UE 115a performs a successful LBT at action 606, the resources may be indicated relative to the start of the COT. UE 115a may also send the resource indicator and the COT indicator to UE 115c and UE 115d, which will share the COT with UE 115a. UE 115c and UE 115d will avoid using the resources indicated by UE 115a. UE 115c and UE 115d may transmit in the COT using resources other than the resources reserved by UE 115a.

[0092] At act 610, UE 115b may send HARQ feedback (e.g., ACK / NACK) to UE 115a via PSFCH communication after a successful LBT (e.g., CAT2 LBT for sharing a COT with UE 115a). If the PSSCH communication is successfully decoded at act 6088, UE 115b may send an ACK. If the PSSCH communication is not successfully decoded at act 608, UE 115b may send a NACK. UE 115b may send HARQ feedback in resources relative to the successful LBT at act 606. If UE 115b sends a NACK, UE 115a may perform LBT (e.g., CAT2 LBT for sharing a COT that has been initiated) relative to the successful LBT at act 606 and / or the first transmission with a first COT indicator for use in a second resource set (e.g., reference 1). Figure 5 retransmit the PSSCH at one of the m2 resources (e.g., reference Figure 5 PSSCH 316) communication (e.g., using an SCI or MAC CE including a second resource indicator for reserved resources and / or a second COT indicator for sharing an already initiated COT, wherein the second COT indicator may indicate a COT duration with an extended period if it is enabled by configuration or by an indication in the first COT indicator) as reserved resources.

[0093] At act 612, the UE 115c sharing the COT may perform a successful LBT to gain access to the channel and share the COT. The UE 115c sharing the COT may, based at least in part on the start of the COT (e.g., the successful LBT at act 606 and / or the first transmission with the first COT indicator), perform a successful LBT to gain access to the channel and share the COT in a first resource set determined by the UE 115c sharing the COT (e.g., the reference signal). Figure 5 p1 resource) for the first transmission (eg, reference Figure 5 PSSCH 310) performs reduced category LBT (e.g., CAT 2 LBT for shared COT).

[0094] At action 614, the UE 115c sharing the COT may communicate with the PSSCH (eg, reference Figure 5 The first transmission is sent on one or more transport blocks on the PSSCH 310 of the SCI or MAC CE, the SCI or MAC CE including at least one for reserving resources (for example, reference Figure 5 p2 resources and / or references Figure 5 The UE 115c may transmit a PSSCH communication in one of the first resource sets determined by the UE 115c based at least in part on the start of the COT (e.g., the successful LBT at action 606 and / or the first transmission with the first COT indicator).

[0095] Figure 7 is a block diagram of an exemplary UE 700 according to some aspects of the present disclosure. UE 700 may be UE 115 or UE 120 in network 100 or 200 as discussed above. As shown, UE 700 may include a processor 702, a memory 704, a COT sharing module 708, a transceiver 710 including a modem subsystem 712 and a radio frequency (RF) unit 714, and one or more antennas 716. These elements may be coupled to each other, for example, via one or more buses and communicate with each other directly or indirectly.

[0096] The processor 702 may include a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 702 may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in combination with a DSP core, or any other such configuration.

[0097] The memory 704 may include cache memory (e.g., cache memory of the processor 702), random access memory (RAM), magnetoresistive RAM (MRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state memory devices, hard drives, other forms of volatile and non-volatile memory, or a combination of different types of memory. In some examples, the memory 704 includes a non-transitory computer-readable medium. The memory 704 may store instructions 706. The instructions 706 may include instructions that, when executed by the processor 702, cause the processor 702 to perform the various aspects of the present disclosure described herein with reference to the UE 115 (e.g., Figures 3 to 6 Instructions 706 may also be referred to as code. The terms "instructions" and "code" should be broadly interpreted to include any type of computer-readable statements. For example, the terms "instructions" and "code" may refer to one or more programs, routines, subroutines, functions, procedures, etc. "Instructions" and "code" may include a single computer-readable statement or multiple computer-readable statements.

[0098] The COT sharing module 708 may be implemented via hardware, software, or a combination thereof. For example, the COT sharing module 708 may be implemented as a processor, a circuit, and / or an instruction 706 stored in the memory 704 and executed by the processor 702. In some aspects, the COT sharing module 708 may be used to perform a first listen-before-talk (LBT) procedure. The COT sharing module 708 may perform a first LBT procedure in an unlicensed band. The COT sharing module 708 may send at least one of the following to the second UE 700 based on the success of the first LBT procedure: a resource indicator indicating a resource associated with a sidelink communication, wherein the resource is indicated relative to when the LBT procedure is successful; or a COT indicator associated with channel occupancy time (COT) sharing. The COT sharing module 708 may send a resource indicator and / or a COT indicator in the same communication (e.g., the same time slot) as the PSSCH. The PSSCH may carry one or more transport blocks.

[0099] As shown, the transceiver 710 may include a modem subsystem 712 and an RF unit 714. The transceiver 710 may be configured to communicate bidirectionally with other devices, such as BS 105 and / or UE 115. The modem subsystem 712 may be configured to modulate and / or encode data from the memory 704 according to a modulation and coding scheme (MCS) (e.g., a low-density parity check (LDPC) decoding scheme, a turbo decoding scheme, a convolutional decoding scheme, a digital beamforming scheme, etc.). The RF unit 714 may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) the modulated / encoded data from the modem subsystem 712 (for outbound transmissions) or transmissions originating from another source, such as UE 115 or BS 105. The RF unit 714 may be further configured to perform analog beamforming in conjunction with digital beamforming. Although shown as integrated together in the transceiver 710, the modem subsystem 712 and the RF unit 714 may be separate devices that are coupled together to enable the UE 700 to communicate with other devices.

[0100] The RF unit 714 may provide modulated and / or processed data, such as a data packet (or more generally, a data message that may include one or more data packets and other information), to the antenna 716 for transmission to one or more other devices. The antenna 716 may also receive data messages sent from other devices. The antenna 716 may provide the received data message for processing and / or demodulation at the transceiver 710. The antenna 716 may include multiple antennas of similar or different designs to maintain multiple transmission links. The RF unit 714 may configure the antenna 716.

[0101] In some examples, the UE 700 may include multiple transceivers 710 that implement different RATs (e.g., NR and LTE). In some examples, the UE 700 may include a single transceiver 710 that implements multiple RATs (e.g., NR and LTE). In some examples, the transceiver 710 may include various components, where different combinations of the components may implement the RATs.

[0102] Figure 8 8 is a block diagram of an exemplary network unit 800 according to some aspects of the present disclosure. The network unit 800 may be a BS 105, a CU 210, a DU 230, or a RU 240 as discussed above. As shown, the network unit 800 may include a processor 802, a memory 804, a COT sharing module 808, a transceiver 810 including a modem subsystem 812 and an RF unit 814, and one or more antennas 816. These elements may be coupled to each other, for example, via one or more buses and communicate with each other directly or indirectly.

[0103] The processor 802 may have various features that are specific types of processors. For example, these features may include a CPU, a DSP, an ASIC, a controller, an FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 802 may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0104] Memory 804 may include cache memory (e.g., cache memory of processor 802), RAM, MRAM, ROM, PROM, EPROM, EEPROM, flash memory, solid-state memory devices, one or more hard disk drives, memristor-based arrays, other forms of volatile and non-volatile memory, or a combination of different types of memory. In some examples, memory 804 may include non-transitory computer-readable media. Memory 804 may store instructions 806. Instructions 806 may include instructions that, when executed by processor 802, cause processor 802 to perform the operations described herein (e.g., Figures 3 to 6 Instructions 806 may also be referred to as codes, which may be broadly interpreted to include any type of computer-readable statements.

[0105] The COT sharing module 808 may be implemented via hardware, software, or a combination thereof. For example, the COT sharing module 808 may be implemented as a processor, circuit, and / or instruction 806 stored in the memory 804 and executed by the processor 802 .

[0106] In some aspects, the COT sharing module 808 can implement Figures 3 to 6 For example, the channel occupancy time (COT) sharing module 808 may receive a first indication associated with COT sharing on the sidelink communication from a first UE (e.g., UE 115, UE 120, or UE 700). The COT sharing module 808 may receive a second indication associated with COT sharing on the sidelink communication from a second UE (e.g., UE 115, UE 120, or UE 700). The COT sharing module 808 may send an indicator for initiating COT on the sidelink communication to the first UE based on the first indication and the second indication. The COT sharing module 808 may send an indicator for sharing COT on the sidelink communication to the second UE based on the first indication and the second indication.

[0107] Additionally or alternatively, the COT sharing module 808 may be implemented in any combination of hardware and software, and in some implementations may involve, for example, the processor 802 , memory 804 , instructions 806 , transceiver 810 , and / or modem 812 .

[0108] As shown, the transceiver 810 may include a modem subsystem 812 and an RF unit 814. The transceiver 810 may be configured to communicate bidirectionally with other devices, such as UE 115 and / or UE 600. The modem subsystem 812 may be configured to modulate and / or encode data according to an MCS (e.g., an LDPC decoding scheme, a turbo decoding scheme, a convolutional decoding scheme, a digital beamforming scheme, etc.). The RF unit 814 may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) the modulated / encoded data from the modem subsystem 812 (for outbound transmissions) or from another source, such as UE 115 or UE 700. The RF unit 814 may be further configured to perform analog beamforming in conjunction with digital beamforming. Although shown as integrated together in the transceiver 810, the modem subsystem 812 and / or the RF unit 814 may be separate devices that are coupled together at the network unit 800 to enable the network unit 800 to communicate with other devices.

[0109] The RF unit 814 may provide modulated and / or processed data, such as data packets (or more generally, data messages that may include one or more data packets and other information), to the antenna 816 for transmission to one or more other devices. For example, according to aspects of the present disclosure, this may include a configuration indicating multiple sub-slots within a time slot. The antenna 816 may also receive data messages sent from other devices and provide the received data messages for processing and / or demodulation at the transceiver 810. The antenna 816 may include multiple antennas of similar design or different designs to maintain multiple transmission links.

[0110] In some examples, the network unit 800 may include multiple transceivers 810 that implement different RATs (e.g., NR and LTE). In some examples, the network unit 800 may include a single transceiver 810 that implements multiple RATs (e.g., NR and LTE). In some examples, the transceiver 810 may include various components, where different combinations of components may implement the RATs.

[0111] Fig. 9900 is a flow chart of a communication method 900 according to some aspects of the present disclosure. Various aspects of the method 900 may be performed by a computing device (e.g., a processor, a processing circuit, and / or other suitable components) of a wireless communication device or other suitable means for performing these aspects. For example, a wireless communication device (such as UE 115, UE 120, or UE 700) may utilize one or more components (such as processor 702, memory 704, COT sharing module 708, transceiver 710, modem 712, and one or more antennas 716) to perform various aspects of the method 900. The method 900 may employ mechanisms similar to those in networks 100 and 200 and with respect to Figures 3 to 6 As shown, method 900 includes multiple enumerated aspects, but method 900 may include additional aspects before, after, and between the enumerated aspects. In some aspects, one or more of these enumerated aspects may be omitted or performed in a different order.

[0112] At action 910, method 900 includes a first side link UE (e.g., UE 115, UE 120, or UE 700) performing a listen-before-talk (LBT) procedure. The first side link UE may perform an LBT procedure or other clear channel assessment (CCA) on one or more side link communication channels. In some instances, the first side link UE may perform an LBT procedure or other CCA to obtain access to a channel occupancy time (COT) in an unlicensed (e.g., shared) spectrum. For example, the first side link UE may perform a category 2 LBT, a category 3 LBT, and / or a category 4 LBT to obtain access to a COT in an unlicensed spectrum. In some aspects, the first side link UE may perform LBT in one or more time resources, space resources, and / or frequency resources. These frequency resources may include spectrum, frequency band, frequency subband, frequency subchannel, resource element, resource block, and / or frequency interleaving. These time resources may include time slots, subslots, symbols, subframes, or any other suitable time resources. In some aspects, the first sidelink UE may perform LBT for one or more directional beams (e.g., beams in the direction of UEs to which the first sidelink UE intends to send communications and / or receive communications from).

[0113] At action 920, method 900 includes: the first side link UE sends at least one of: a resource indicator indicating resources associated with the side link communication; or a COT indicator associated with channel occupancy time (COT) sharing. In this regard, the first side link UE may send a resource indicator and / or a COT indicator via SCI-1 on PSCCH, SCI-2 multiplexed with PSSCH, MAC CE on PSSCH, or other suitable communications. In some aspects, the first side link UE may send a resource indicator and / or a COT indicator to a side link UE with which the first side link UE intends to communicate. The first side link UE may send a resource indicator and / or a COT indicator in the same communication (e.g., the same time slot) as the PSSCH. The PSSCH may carry one or more transport blocks. Additionally or alternatively, the first side link UE may send a resource indicator and / or a COT indicator to other side link UEs with which the first side link UE intends to share the COT. For example, the first side link UE may intend to share the COT with other side link UEs near the first side link UE. In some aspects, based on the LBT procedure at act 910 being successful, the first sidelink UE may send a resource indicator and / or a COT indicator.

[0114] In some aspects, the resource indicator sent by the first side link UE may indicate resources associated with the side link communication relative to when the LBT procedure is successful. For example, if the first side link UE performs a successful LBT at time slot i, the resource indicator may indicate resources associated with the side link communication relative to time slot i. In some instances, the resource indicator may indicate resources associated with the side link communication as a number (e.g., an integer number) of time slots, a number of sub-time slots, or a number of symbols starting from time slot i (e.g., the end of time slot i and / or the beginning of time slot i). In some aspects, the resource indicator may indicate resources associated with the side link communication as a time value (e.g., a number of milliseconds) relative to time slot i.

[0115] In some aspects, the COT indicator sent by the first side link UE may indicate a COT identifier (ID), the start of the COT, and / or the duration of the COT. In some aspects, the side link UE may receive one or more COT indicators from other side link UEs (including the first side link UE), indicating multiple COT identifiers. The COT identifier may identify one or more COTs that the first side link UE may initiate and share with the side link UEs sharing the COT. The first side link UE may send a COT identifier to the UEs sharing the COT (e.g., the third side link UE, the fourth side link UE, etc.) via one or more side link communications (e.g., via SCI-1, SCI-2, MAC CE) after a successful LBT. The COT identifier may identify a COT that may be shared between side link UEs near each other. The location associated with the first side link UE (e.g., zone identification, beam coverage pattern, cell sector, latitude / longitude range, geo-fence, etc.) may be used to determine aspects of COT sharing for one or more UEs sharing the COT among the first side link UE and other UEs sharing the COT. In some aspects, the first sidelink UE may determine its location based on GPS coordinates, radio frequency triangulation, or other suitable methods. Additionally or alternatively, the first sidelink UE may determine its location based on a zone identification associated with the first sidelink UE. In this regard, the first UE may determine its zone identification based on Section 5.8.11 of 3GPP TS 38.331 or other standard specifications related to zone identification.

[0116] Additionally or alternatively, the network unit (e.g., BS105, RU 240, DU 230, CU 210, and / or network unit 800) may determine the COT identifier and / or the COT duration based on the location of the first side link UE and / or the location of one or more other UEs sharing the COT near the first side link UE. For example, the network unit may determine whether the first side link UE can be configured as a COT initiating UE and / or a COT sharing UE based on the location of the first side link UE and / or the location of one or more other UEs near the first side link UE. When the first side link UE is determined to be a COT initiator, the network unit may send the COT identifier and / or the COT duration to the first side link UE.

[0117] In some aspects, the COT indicator sent by the first side link UE may indicate the COT duration. The COT duration may indicate the time period of the COT in which the side link UE shares the first side link UE and the UE sharing the COT can communicate. The COT duration may start from a successful LBT performed by the first side link UE. In some aspects, the COT duration may be based on the amount of data (e.g., transport blocks) that the first side link UE and the UE sharing the COT need to send. Compared with a smaller amount of data, a larger amount of data may require a longer COT duration. The COT duration may be indicated to the UE sharing the COT as a number of time slots, a number of sub-time slots, a number of symbols, a number of milliseconds, or a combination thereof. In some aspects, the COT duration may indicate the remaining COT duration. For example, the COT duration may be the duration of x time slots. The first side link UE may use y time slots in x time slots to send side link communications. The remaining COT duration may be indicated to the second side link UE and / or other side link UEs sharing the COT as xy time slots. In some aspects, the COT duration may be indicated as a COT extension. The first side link UE may initially indicate the COT duration as x time slots. The first side link UE may subsequently indicate the COT duration as x+z time slots. For example, the first side link UE may indicate the COT extension in a subsequent transmission (e.g., a second transmission, a third transmission, or other subsequent transmission) as x+z time slots. In some aspects, the COT may be extended based on the need for retransmissions due to a failed initial transmission (e.g., the first side link UE receiving a NACK from the second side link UE).

[0118] In some aspects, the starting point (e.g., starting time slot, starting sub-time slot, and / or starting symbol) of the COT may be based on the first side link UE performing a successful LBT at 910. For example, the first side link UE may have resources reserved in time slot (i), time slot (i+1), time slot (i+2), etc. The resources may be a set of resources of a resource pool. The resource sets may each include a number of time slots (e.g., consecutive time slots), a number of sub-time slots (e.g., consecutive sub-time slots), and / or a number of symbols (e.g., consecutive symbols).

[0119] In some aspects, the first side link UE may receive an indication of a resource pool from a network element, indicating resources reserved for the first side link UE. Time slot (i), time slot (i+1), time slot (i+2), etc. may be continuous or discontinuous in time. The first side link UE may perform LBT before time slot (i) to obtain access to the COT during time slot (i). If the LBT is unsuccessful, the first side link UE may wait for a period of time (e.g., a backoff period) to perform another LBT. For example, the first side link UE may wait until the offset of the next time slot boundary between time slot (i) and time slot (i+1) to perform another LBT. If the subsequent LBT is successful, the first side link UE may obtain a COT starting at time slot (i+1). When the LBT is successful, the first side link UE may send a resource indicator and / or a COT indicator to the second side link UE and other UEs sharing the COT. For example, if LBT is successful at time slot (i+1), the COT indicator may indicate that COT starts at time slot (i+1). Other UEs sharing the COT will share the COT in resources relative to time slot (i+1). For example, when the first side link UE obtains COT at time slot (i+1), the first side link UE may send a resource indicator and / or a COT indicator to other UEs sharing the COT in time slot (i+1) (e.g., via SCI). One of the other UEs sharing the COT (e.g., a third side link UE) may send side link communications in the next time slot (i+2). The third side link UE may send side link communications in time slot (i+2) after a successful LBT (e.g., a streamlined category LBT such as Cat 2 LBT). If the first sidelink UE requires additional time slots for sidelink communication (e.g., 2 or more time slots for initial communication), the first sidelink UE may transmit in time slots (i+1), (i+2), (i+x). The third sidelink UE may transmit in time slot (i+x+2) after the first sidelink UE.

[0120] The resource allocation sent by the first side link UE may indicate the reserved resources that the first side link UE can use to send and / or resend the side link communication. In some instances, the resource allocation may indicate the time resources (e.g., time slots, sub-time slots, and / or symbols) that the first side link UE is to send relative to when the first side link UE performs a successful LBT. In some aspects, the first side link UE may be allocated one or more resource sets (e.g., several consecutive time slots). For example, the first side link UE may have a first resource set allocated for initial side link transmission, a second resource set allocated for transmission or retransmission, and a third resource set allocated for transmission or retransmission. The second resource set may be indicated as x time slots after the first resource set. The third resource set may be indicated as y time slots after the first resource set. In some aspects, x may be the same as or different from y. In some aspects, y may be greater than x.

[0121] In some aspects, a time interval (e.g., x time slots) between a first resource in a first resource set and a first resource in a second resource set may be based on a time required for a receiving sidelink UE to process a received transmission and generate / send associated HARQ feedback, and / or a time required for the first sidelink UE to receive and process the HARQ feedback and generate / send a retransmission (e.g., based on the HARQ feedback being a NACK). Similarly, a time interval (e.g., y time slots) between a first resource in a first resource set and a first resource in a third resource set may be based on a time required for a receiving sidelink UE to process a received transmission and generate / send associated HARQ feedback, and / or a time required for the first sidelink UE to receive and process the HARQ feedback and generate / send a second retransmission (e.g., based on the HARQ feedback being a second NACK). A sidelink UE receiving a transmission from a first sidelink UE may send HARQ feedback to the first sidelink UE in a resource relative to a transmission made by the first sidelink UE. For example, if the first side link UE performs a successful LBT just before time slot (i+1) and sends communication in time slot (i+1), the receiving side link UE may send HARQ feedback in time slot (i+1+n), where n is the number of time slots relative to the transmission in time slot (i+1).

[0122] At action 930, the method 900 includes: the first sidelink UE sends a sidelink communication (e.g., one or more transport blocks) to the second sidelink UE during the COT based on the success of the first LBT procedure. In this regard, the first sidelink UE may send the sidelink communication to the second sidelink UE via SCI-1, SCI-2, MAC CE, or other suitable communication.

[0123] The first side link UE may perform LBT before (e.g., immediately before) the resources allocated to the first side link UE to obtain access to the COT. If the LBT is successful, the first side link UE may send a side link communication to the second side link UE during the COT. If the LBT is unsuccessful, the first side link UE may wait for a period of time (e.g., a backoff period) to perform another LBT. For example, the first side link UE may wait until an offset from the next slot boundary, subslot boundary, or symbol boundary to perform another LBT. If the subsequent LBT is successful, the first side link UE may obtain a COT starting at a slot boundary, subslot boundary, or symbol boundary, and send a side link communication to the second side link UE during the COT. Relative to the start of the COT (e.g., a successful LBT), the side link communication may include an SCI indicating the COT duration, COT ID, and / or resources.

[0124] Fig.10 1 is a flow chart of a communication method 1000 according to some aspects of the present disclosure. Various aspects of the method 1000 may be performed by a computing device (e.g., a processor, a processing circuit, and / or other suitable components) of a wireless communication device or other suitable means for performing these aspects. For example, a wireless communication device (such as UE 115, UE 120, or UE 700) may utilize one or more components (such as a processor 702, a memory 704, a COT sharing module 708, a transceiver 710, a modem 712, and one or more antennas 716) to perform various aspects of the method 1000. The method 1000 may employ mechanisms similar to those in the networks 100 and 200 and with respect to Figures 3 to 6 As shown, method 1000 includes multiple enumerated aspects, but method 1000 may include additional aspects before, after, and between the enumerated aspects. In some aspects, one or more of these enumerated aspects may be omitted or performed in a different order.

[0125] At action 1010, method 1000 includes: a first side link UE (e.g., UE 115, UE 120, or UE 700) receives from a second side link UE at least one of: a resource indicator indicating resources associated with side link communication; or a COT indicator associated with channel occupancy time (COT) sharing. In this regard, the first side link UE may receive the resource indicator and / or COT indicator via SCI-1, SCI-2, MAC CE, or other suitable communication. In some aspects, the first side link UE may receive the resource indicator and / or COT indicator from the second side link UE with which the first side link UE intends to communicate. Additionally or alternatively, the first side link UE may receive the resource indicator and / or COT indicator from other side link UEs with which the first side link UE intends to share the COT. For example, the first side link UE may intend to share the COT with other side link UEs near the first side link UE.

[0126] In some aspects, a resource indicator received by a first side link UE may indicate resources associated with side link communications relative to when an LBT procedure performed by a second side link UE is successful. For example, if the second side link UE performs a successful LBT at time slot i, the resource indicator may indicate resources associated with side link communications relative to time slot i. In some instances, the resource indicator may indicate resources associated with side link communications as a number (e.g., an integer number) of time slots, a number of sub-time slots, or a number of symbols starting from time slot i (e.g., the end of time slot i and / or the beginning of time slot i). In some aspects, the resource indicator may indicate resources associated with side link communications as a time value (e.g., a number of milliseconds) relative to time slot i.

[0127] In some aspects, the COT indicator received by the first side link UE may indicate a COT identifier (ID), the start of the COT, and / or the duration of the COT. In some aspects, the side link UE may receive one or more COT indicators indicating multiple COT identifiers from other side link UEs (including the second side link UE). The COT identifier may identify one or more COTs that the second side link UE may initiate and share with the side link UEs sharing the COT. The first side link UE may receive a COT identifier from a UE sharing the COT (e.g., a third side link UE, a fourth side link UE, etc.) via one or more side link communications (e.g., via SCI-1, SCI-2, MAC CE) after a successful LBT. The COT identifier may identify a COT that may be shared between side link UEs near each other. The location associated with the first side link UE (e.g., zone identification, beam coverage pattern, cell sector, latitude / longitude range, geo-fence, etc.) may be used to determine aspects of COT sharing for one or more UEs sharing the COT among the first side link UE and other UEs sharing the COT. In some aspects, the first sidelink UE may determine its location based on GPS coordinates, radio frequency triangulation, or other suitable methods. Additionally or alternatively, the first sidelink UE may determine its location based on a zone identification associated with the first sidelink UE. In this regard, the first UE may determine its zone identification based on Section 5.8.11 of 3GPP TS 38.331 or other standard specifications related to zone identification.

[0128] Additionally or alternatively, the network unit (e.g., BS105, RU 240, DU 230, CU 210, and / or network unit 800) may determine the COT identifier and / or the COT duration based on the location of the first side link UE and / or the location of one or more other UEs sharing the COT near the first side link UE. For example, the network unit may determine whether the first side link UE can be configured as a COT initiating UE and / or a COT sharing UE based on the location of the first side link UE and / or the location of one or more other UEs near the first side link UE. When the first side link UE is determined to be a COT initiator, the network unit may send the COT identifier and / or the COT duration to the first side link UE.

[0129] In some aspects, the COT indicator received by the first side link UE may indicate the COT duration. The COT duration may indicate the time period of the COT in which the side link UE shares the first side link UE and the UE sharing the COT can communicate. The COT duration may start from a successful LBT performed by the second side link UE. In some aspects, the COT duration may be based on the amount of data (e.g., transport blocks) that the first side link UE and the UE sharing the COT need to send. Compared with a smaller amount of data, a larger amount of data may require a longer COT duration. The COT duration may be indicated to the UE sharing the COT as a number of time slots, a number of sub-time slots, a number of symbols, a number of milliseconds, or a combination thereof. In some aspects, the COT duration may indicate the remaining COT duration. For example, the COT duration may be the duration of x time slots. The second side link UE may use y time slots in x time slots to send side link communications. The remaining COT duration may be indicated to the first side link UE and / or other side link UEs sharing the COT as xy time slots. In some aspects, the COT duration may be indicated as a COT extension. The second side link UE may initially indicate the COT duration as x time slots. The second side link UE may subsequently indicate the COT duration as x+z time slots. For example, the second side link UE may indicate a COT extension in a subsequent transmission (e.g., a second transmission, a third transmission, or other subsequent transmission) as x+z time slots. In some aspects, the COT may be extended based on a failed initial transmission (e.g., the second side link UE receives a NACK from the third side link UE) requiring a retransmission.

[0130] In some aspects, the starting point (e.g., starting time slot, starting sub-time slot, and / or starting symbol) of the COT may be based on the second side link UE performing a successful LBT. For example, the second side link UE may have resources reserved in time slot (i), time slot (i+1), time slot (i+2), etc. These resources may be resource sets of a resource pool. The resource sets may each include a number of time slots (e.g., consecutive time slots), a number of sub-time slots (e.g., consecutive sub-time slots), and / or a number of symbols (e.g., consecutive symbols).

[0131] In some aspects, the second side link UE may receive an indication of a resource pool from a network element, indicating resources reserved for the first side link UE. Time slot (i), time slot (i+1), time slot (i+2), etc. may be continuous or discontinuous in time. The second side link UE may perform LBT before time slot (i) to obtain access to the COT during time slot (i). If the LBT is unsuccessful, the second side link UE may wait for a period of time (e.g., a backoff period) to perform another LBT. For example, the second side link UE may wait until the offset of the next time slot boundary between time slot (i) and time slot (i+1) to perform another LBT. If the subsequent LBT is successful, the second side link UE may obtain a COT starting at time slot (i+1). When the LBT is successful, the second side link UE may send a resource indicator and / or a COT indicator to the first side link UE and other UEs sharing the COT. For example, if the LBT is successful at time slot (i+1), the COT indicator may indicate that the COT starts at time slot (i+1). The first side link UE and other UEs sharing the COT will share the COT in resources relative to time slot (i+1). For example, when the second side link UE obtains the COT at time slot (i+1), the second side link UE may send a resource indicator and / or a COT indicator to the first side link UE and other UEs sharing the COT in time slot (i+1) (e.g., via SCI). The first side link UE may send side link communication in the next time slot (i+2). The first side link UE may send side link communication in time slot (i+2) after a successful LBT (e.g., a streamlined category LBT such as Cat 2 LBT). If the second side link UE requires additional time slots for side link communication (e.g., 2 or more time slots for initial communication), the second side link UE may send in time slots (i+1), (i+2), (i+x). The first sidelink UE may share the COT and transmit in time slot (i+x+2) after the second sidelink UE starts.

[0132] The resource allocation received by the first side link UE may indicate the reserved resources that the first side link UE can use to send and / or resend the side link communication. In some instances, the resource allocation may indicate the time resources (e.g., time slots, sub-time slots, and / or symbols) that the first side link UE is to send relative to the second side link UE when performing a successful LBT. In some aspects, the first side link UE may be allocated one or more resource sets (e.g., several consecutive time slots). For example, the first side link UE may have a first resource set allocated for initial side link transmission, a second resource set allocated for transmission or retransmission, and a third resource set allocated for transmission or retransmission. The second resource set may be indicated as x time slots after the first resource set. The third resource set may be indicated as y time slots after the first resource set. In some aspects, x may be the same as or different from y. In some aspects, y may be greater than x.

[0133] In some aspects, a time interval (e.g., x time slots) between a first resource in a first resource set and a first resource in a second resource set may be based on a time required for a receiving sidelink UE to process a received transmission and generate / send associated HARQ feedback, and / or a time required for the first sidelink UE to receive and process the HARQ feedback and generate / send a retransmission (e.g., based on the HARQ feedback being a NACK). Similarly, a time interval (e.g., y time slots) between a first resource in a first resource set and a first resource in a third resource set may be based on a time required for a receiving sidelink UE to process a received transmission and generate / send associated HARQ feedback, and / or a time required for the first sidelink UE to receive and process the HARQ feedback and generate / send a second retransmission (e.g., based on the HARQ feedback being a second NACK). A sidelink UE receiving a transmission from a first sidelink UE may send HARQ feedback to the first sidelink UE in a resource relative to a transmission made by the first sidelink UE. For example, if the first side link UE performs a successful LBT (e.g., CAT 2 LBT) just before time slot (i+2) and sends communication in time slot (i+2), the receiving side link UE may send HARQ feedback in time slot (i+2+n), where n is the number of time slots relative to the transmission in time slot (i+2).

[0134] At action 1020, method 1000 includes: a first side link UE (e.g., UE 115, UE 120, or UE 700) performs a listen-before-talk (LBT) procedure. The first side link UE may perform an LBT procedure or other clear channel assessment (CCA) on one or more side link communication channels. In some instances, after receiving a resource indicator and / or a channel occupancy time (COT) indicator from a second side link UE, the first side link UE may perform an LBT procedure or other CCA to obtain access to the COT in an unlicensed (e.g., shared) spectrum. In this way, the first side link UE shares the COT with the second side link UE and other side link UEs that share the COT. For example, the first side link UE may perform Category 2 LBT, Category 3 LBT, and / or Category 4 LBT to obtain access to the COT in an unlicensed spectrum. In some aspects, the first side link UE may perform LBT in one or more time resources, space resources, and / or frequency resources. These frequency resources may include spectrum, frequency band, frequency sub-band, frequency sub-channel, resource element, resource block and / or frequency interlace. These time resources may include time slot, sub-time slot, symbol, subframe or any other suitable time resource. In some aspects, the first side link UE may perform LBT for one or more directional beams (e.g., beams in the direction of UEs to which the first side link UE intends to send communications and / or receive communications from).

[0135] At act 1030, method 1000 includes the first sidelink UE sending a sidelink communication (e.g., one or more transport blocks) to a third sidelink UE during the COT based on the LBT procedure success at act 1020. In this regard, the first sidelink UE may send the sidelink communication to the third sidelink UE via SCI-1, SCI-2, MAC CE, or other suitable communication. The first sidelink UE may send the sidelink communication to the third sidelink UE during the COT based on the resource indicator and / or COT indicator received from the second sidelink UE at act 1010.

[0136] Other aspects of the present disclosure include the following:

[0137] Aspect 1 includes a method of wireless communication performed by a first sidelink user equipment (UE), the method comprising: performing a first listen-before-talk (LBT) procedure; sending at least one of the following to a second sidelink UE based on the success of the first LBT procedure: a resource indicator indicating resources associated with sidelink communication, wherein the resources are indicated relative to when the first LBT procedure is successful; or a channel occupancy time (COT) indicator associated with COT sharing.

[0138] Aspect 2 includes a method according to aspect 1, wherein sending at least one of the resource indicator or the COT indicator includes: sending the resource indicator, wherein the resource indicator indicates the resource as an integer number of time slots relative to when the LBT procedure is successful.

[0139] Aspect 3 includes a method according to any one of Aspects 1 to 2, wherein sending the at least one of the resource indicator or the COT indicator includes: sending the at least one of the resource indicator or the COT indicator via sidelink control information (SCI).

[0140] Aspect 4 includes a method according to any one of aspects 1 to 3, wherein sending at least one of the resource indicator or the COT indicator includes: sending the resource indicator, wherein the resource indicator also indicates a minimum time interval between the resources associated with the side link communication.

[0141] Aspect 5 includes a method according to any one of Aspects 1 to 4, wherein sending at least one of the resource indicator or the COT indicator includes: sending the resource indicator, wherein the resources associated with the side link communication include resources reserved for sending the side link communication during the COT.

[0142] Aspect 6 includes a method according to any one of Aspects 1 to 5, the method further comprising: performing a second LBT procedure in a first resource before the first LBT procedure; and wherein sending at least one of the resource indicator or the COT indicator includes: sending at least one of the resource indicator or the COT indicator in a second resource different from the first resource based on the failure of the second LBT procedure.

[0143] Aspect 7 includes a method according to any one of Aspects 1 to 6, wherein sending at least one of the resource indicator or the COT indicator includes: sending the resource indicator; and the method also includes: receiving an acknowledgment / negative acknowledgment (ACK / NACK) associated with the side link communication from the second side link UE in the resource relative to when the first LBT procedure is successful.

[0144] Aspect 8 includes a method according to any one of Aspects 1 to 7, the method further comprising: sending at least one of the following to a third side link UE based on the success of the first LBT procedure: the resource indicator indicating the resources associated with the side link communication; or the COT indicator associated with COT sharing.

[0145] Aspect 9 includes the method of any one of aspects 1 to 8, wherein the COT indicator further indicates that the third sidelink UE shares the COT based at least in part on the indicated resources; and the COT indicator further indicates a COT duration.

[0146] Aspect 10 includes a method according to any one of Aspects 1 to 9, wherein the COT duration indicates a time period for sharing the COT between sidelink UEs near the first sidelink UE; and the COT duration is at least partially based on the number of the sidelink UEs near the first sidelink UE.

[0147] Aspect 11 includes a method of wireless communication performed by a first sidelink user equipment (UE), the method comprising: receiving from a second sidelink UE: a first resource indicator indicating resources associated with sidelink communication, wherein the resources are indicated relative to the beginning of a first channel occupancy time (COT); sharing the first COT indicator associated with the COT; performing a first listen-before-talk (LBT) procedure; and sending sidelink communication to a third sidelink UE during the COT based on success of the first LBT procedure and at least in part on the received resource indicator or the COT indicator.

[0148] Aspect 12 includes the method of aspect 11, wherein the resource indicator indicates the resource as an integer number of time slots relative to the beginning of the first COT.

[0149] Aspect 13 includes a method according to any one of aspects 11 to 12, wherein receiving the resource indicator and the COT indicator includes: receiving the resource indicator and the COT indicator via sidelink control information (SCI).

[0150] Aspect 14 includes a method according to any one of aspects 11 to 13, wherein the resource indicator further indicates a minimum time interval between the resources associated with the sidelink communication.

[0151] Aspect 15 includes a method according to any one of aspects 11 to 14, wherein the resources associated with the sidelink communication include resources reserved for retransmitting the sidelink communication during the COT.

[0152] Aspect 16 includes a method according to any one of Aspects 11 to 15, the method further comprising: receiving an acknowledgment / negative acknowledgment (ACK / NACK) associated with the sidelink communication from the third sidelink UE in the resources relative to when the first LBT procedure is successful.

[0153] Aspect 17 includes the method according to any one of aspects 11 to 16, wherein the COT indicator further indicates that the COT is shared using the indicated resources; and the COT indicator further indicates a COT duration.

[0154] Aspect 18 includes a method according to any one of aspects 11 to 17, wherein the COT duration indicates a time period for sharing the COT between sidelink UEs in the vicinity of the first sidelink UE.

[0155] Aspect 19 includes a method according to any one of Aspects 11 to 18, the method further comprising: sending to the second side link UE and / or the third side link UE based on the success of the first LBT procedure: a second resource indicator indicating resources associated with the side link communication, wherein the resources are indicated relative to the beginning of the first channel occupancy time (COT); and the second COT indicator associated with COT sharing.

[0156] Aspect 20 includes the method according to any one of aspects 11 to 19, wherein the second COT indicator further indicates the COT identifier as indicated in the first COT indicator.

[0157] Aspect 21 includes a method according to any one of Aspects 11 to 20, wherein the second COT indicator also indicates the COT duration as: the COT duration indicated in the first COT indicator; a remaining COT duration based at least in part on the COT duration indicated in the first COT indicator; or a COT duration including an extension of the COT duration indicated in the first COT indicator.

[0158] Aspect 22 includes the method according to any one of aspects 11 to 18, wherein the COT indicator further indicates that the COT is shared using the indicated resources; and the COT indicator further indicates a COT identifier.

[0159] Aspect 23 includes a non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions including one or more instructions that, when executed by one or more processors of a first side link UE, cause the first side link UE to perform any one of aspects 1 to 10.

[0160] Aspect 24 includes a non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions including one or more instructions that, when executed by one or more processors of the first side link UE, cause the first side link UE to perform any one of aspects 11 to 22.

[0161] Aspect 25 includes a first sidelink user equipment (UE), the first sidelink user equipment (UE) comprising one or more components for performing any one or more of aspects 1 to 10.

[0162] Aspect 26 includes a first sidelink UE comprising one or more components for performing any one or more of aspects 11-22.

[0163] Information and signals 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 mentioned throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0164] The various illustrative blocks and modules described in conjunction with the disclosure herein may be implemented or executed using a general purpose processor, DSP, ASIC, 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 an alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration).

[0165] 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 as one or more instructions or codes on a computer-readable medium, or sent via a computer-readable medium. Other examples and specific implementations are within the scope of the present disclosure and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software, hardware, firmware, hard wiring, or any combination thereof executed by a processor. The features that implement the functions may also be physically located at different locations, including being distributed so that the parts of the functions are implemented at different physical locations. In addition, as used herein (including in the claims), as used in an item enumeration (e.g., followed by an item enumeration such as "at least one of" or "one or more of"), "or" indicates an inclusive enumeration, such that, for example, an enumeration 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).

[0166] As those skilled in the art will understand by now and depending on the specific application at hand, many modifications, substitutions and changes may be made to the materials, devices, configurations and methods of use of the apparatus of the present disclosure without departing from the spirit and scope of the present disclosure. In view of this, the scope of the present disclosure should not be limited to the scope of the specific examples illustrated and described herein (because they are only some examples thereof), but should be fully equivalent to the claims attached hereto and their functional equivalents.

Claims

1. A method of wireless communication performed by a first sidelink user equipment (UE), the method comprising: Implement the Listen First, Talk Later (LBT) protocol; as well as Sending at least one of the following to the second sidelink UE based on the success of the first LBT procedure: a resource indicator indicating resources associated with sidelink communications, wherein the resources are indicated relative to when the LBT procedure is successful; or A Channel Occupancy Time (COT) indicator associated with COT sharing.

2. The method of claim 1 , wherein sending the at least one of the resource indicator or the COT indicator comprises: The resource indicator is sent, wherein the resource indicator indicates the resource as an integer number of time slots relative to when the LBT procedure is successful.

3. The method of claim 1 , wherein sending the at least one of the resource indicator or the COT indicator comprises: The resource indicator is sent, wherein the resources associated with the sidelink communication include resources reserved for sending the sidelink communication during a COT.

4. The method according to claim 1, further comprising: In a first resource, executing a second LBT procedure before the first LBT procedure; and Wherein sending the at least one of the resource indicator or the COT indicator comprises sending the at least one of the resource indicator or the COT indicator in a second resource different from the first resource based on the failure of the second LBT procedure.

5. The method of claim 1 , wherein sending the at least one of the resource indicator or the COT indicator comprises: sending the resource indicator; and The method further comprises: An acknowledgement / negative acknowledgement (ACK / NACK) associated with the sidelink communication is received from the second sidelink UE in the resources relative to when the first LBT procedure is successful.

6. The method according to claim 1, further comprising: Sending at least one of the following to a third sidelink UE based on the success of the first LBT procedure: the resource indicator indicating the resource associated with the sidelink communication; or The COT indicator associated with COT sharing.

7. The method according to claim 6, wherein: The COT indicator further instructs the third sidelink UE to share the COT based at least in part on the indicated resources; and The COT indicator also indicates a COT identifier.

8. The method according to claim 6, wherein: The COT indicator further instructs the third sidelink UE to share the COT based at least in part on the indicated resources; and The COT indicator also indicates the COT duration.

9. The method according to claim 8, wherein: The COT duration indicates a time period for sharing the COT between sidelink UEs near the first sidelink UE.

10. A method of wireless communication performed by a first sidelink user equipment (UE), the method comprising: Received from the second sidelink UE: a first resource indicator indicating resources associated with sidelink communications, wherein the resources are indicated relative to a beginning of a first channel occupancy time (COT); and a first COT indicator associated with COT sharing; Implement the Listen First, Talk Later (LBT) protocol; as well as Sending a sidelink communication to a third sidelink UE during the first COT based on the first LBT procedure being successful and based at least in part on the first resource indicator or the first COT indicator.

11. The method of claim 10, wherein the first resource indicator indicates the resource as an integer number of time slots relative to the beginning of the first COT.

12. The method of claim 10, wherein receiving the first resource indicator and the first COT indicator comprises: The first resource indicator and the first COT indicator are received via sidelink control information (SCI).

13. The method of claim 10, wherein the resources associated with the sidelink communication comprise resources reserved for sending the sidelink communication during the first COT.

14. The method according to claim 10, further comprising: An acknowledgement / negative acknowledgement (ACK / NACK) associated with the sidelink communication is received from the third sidelink UE in the resources relative to when the first LBT procedure is successful.

15. The method of claim 10, wherein: The first COT indicator further indicates that the first COT is shared using the indicated resources; and The first COT indicator also indicates a COT identifier.

16. A first sidelink user equipment (UE), the first sidelink user equipment (UE) comprising: Memory; Transceiver; and at least one processor coupled to the memory and the transceiver, wherein the first sidelink UE is configured to: Implementing the Listen Before Talk (LBT) protocol; and Sending at least one of the following to the second sidelink UE based on the success of the first LBT procedure: a resource indicator indicating resources associated with sidelink communications, wherein the resources are indicated relative to when the first LBT procedure is successful; or A Channel Occupancy Time (COT) indicator associated with COT sharing.

17. The first sidelink UE according to claim 16, wherein the first sidelink UE is further configured to: The resource indicator is sent, wherein the resource indicator indicates the resource as an integer number of time slots relative to when the first LBT procedure is successful.

18. The first sidelink UE according to claim 16, wherein the first sidelink UE is further configured to: The resource indicator is sent, wherein the resources associated with the sidelink communication include resources reserved for sending the sidelink communication during a COT.

19. The first sidelink UE according to claim 16, wherein the first sidelink UE is further configured to: In a first resource, performing a second LBT procedure before the first LBT procedure; and The at least one of the resource indicator or the COT indicator is sent in a second resource different from the first resource based on the second LBT procedure being unsuccessful.

20. The first sidelink UE of claim 16, wherein the first sidelink UE is further configured to: sending the resource indicator; and An acknowledgement / negative acknowledgement (ACK / NACK) associated with the sidelink communication is received from the second sidelink UE in the resources relative to when the first LBT procedure is successful.

21. The first sidelink UE of claim 16, wherein the first sidelink UE is further configured to: Sending at least one of the following to a third sidelink UE based on the success of the first LBT procedure: the resource indicator indicating the resource associated with the sidelink communication; or The COT indicator associated with COT sharing.

22. The first sidelink UE according to claim 21, wherein: The COT indicator further instructs the third sidelink UE to share the COT based at least in part on the indicated resources; and The COT indicator also indicates a COT identifier.

23. The first sidelink UE of claim 21, wherein: The COT indicator further instructs the third sidelink UE to share the COT based at least in part on the indicated resources; and The COT indicator also indicates the COT duration.

24. The first sidelink UE of claim 23, wherein: The COT duration indicates a time period for sharing the COT between sidelink UEs near the first sidelink UE.

25. A first sidelink user equipment (UE), the first sidelink user equipment (UE) comprising: Memory; Transceiver; and at least one processor coupled to the memory and the transceiver, wherein the first sidelink UE is configured to: Received from the second sidelink UE: a first resource indicator indicating resources associated with sidelink communications, wherein the resources are indicated relative to a beginning of a first channel occupancy time (COT); and a first COT indicator associated with COT sharing; Implement the Listen First, Talk Later (LBT) protocol; as well as Sending a sidelink communication to a third sidelink UE during the first COT based on the first LBT procedure being successful and based at least in part on the first resource indicator or the first COT indicator.

26. The first sidelink UE of claim 25, wherein the resource indicator indicates the resources as an integer number of time slots relative to the beginning of the first COT.

27. The first sidelink UE of claim 25, wherein the first sidelink UE is further configured to: The first resource indicator and the first COT indicator are received via sidelink control information (SCI).

28. The first sidelink UE of claim 25, wherein the resources associated with the sidelink communication comprise resources reserved for sending the sidelink communication during the first COT.

29. The first sidelink UE of claim 25, wherein the first sidelink UE is further configured to: An acknowledgement / negative acknowledgement (ACK / NACK) associated with the sidelink communication is received from the third sidelink UE in the resources relative to when the first LBT procedure is successful.

30. The first sidelink UE of claim 25, wherein: The first COT indicator further indicates that the first COT is shared using the indicated resources; and The first COT indicator also indicates a COT identifier.

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