Channel occupancy sharing for sidelink feedback channel transmissions

Abstract

Aspects of the present disclosure relate to receiving sidelink control information (SCI) that allocates resources for a physical sidelink shared channel (PSSCH) transmission, the SCI including a field indicating a COT duration of a first channel occupancy time (COT), and transmitting hybrid automatic repeat request (HARQ) feedback in a physical sidelink feedback channel (PSFCH) transmission within the COT duration, and another COT is not initiated based on the SCI. The receiving UE may determine the COT duration indicated by the SCI as being shared for transmission of HARQ feedback on the PSFCH.

Description

Technical Field

[0001] The present disclosure relates to wireless communications and, more particularly, to sharing channel occupancy time in unlicensed spectrum. Background Art

[0002] A wireless communication system may include one or more network communication devices (such as base stations), which may be referred to as eNodeB (eNB), next generation NodeB (gNB) or other suitable terms. Each network communication device (such as a base station) may support wireless communication of one or more user communication devices, which may also be referred to as user equipment (UE) or other suitable terms. A wireless communication system may support wireless communication with one or more user communication devices by utilizing resources of a wireless communication system (e.g., time resources (e.g., symbols, time slots, subframes, frames, etc.) or frequency resources (e.g., subcarriers, carriers)). In addition, a wireless communication system may support wireless communication across various radio access technologies, including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, and other suitable radio access technologies beyond 5G (e.g., sixth generation (6G)).

[0003] A network node operating in an unlicensed spectrum may need to perform a clear channel assessment (CCA), also known as channel sensing, such as by listen before talk (LBT), before transmitting in the unlicensed spectrum. If a network node performing LBT does not detect the presence of other signals in the channel, the channel is considered available for transmission.

[0004] In the frame-based equipment (FBE) mode of operation, the network node performs LBT during idle periods (e.g., at the end of each idle period). After acquiring the channel, the network node can communicate during non-idle time of a fixed frame period duration, called the channel occupation time (COT). The LBT process takes time and processing resources. Summary of the invention

[0005] The present disclosure relates to methods, apparatus, and systems that support shared channel occupancy time (COT) for physical sidelink feedback channel (PSFCH) transmissions.

[0006] Some implementations of the methods and apparatus described herein may also include receiving sidelink control information (SCI) that allocates resources for a physical sidelink shared channel (PSSCH) transmission, the SCI including a field indicating a COT duration of a first channel occupancy time (COT), and sending hybrid automatic repeat request (HARQ) feedback in a physical sidelink feedback channel (PSFCH) transmission within the COT duration without initiating another COT based on the SCI.

[0007] In some implementations of the methods and apparatus described herein, the COT duration is extracted from the SCI, and when the PSFCH transmission falls within the COT duration extracted from the SCI, the UE sends HARQ feedback without initiating another COT.

[0008] In some implementations of the methods and apparatus described herein, a COT duration indicated by the SCI is determined to be shared for transmission of HARQ feedback on the PSFCH.

[0009] In some implementations of the methods and apparatus described herein, the UE determines whether to initiate another COT before sending HARQ feedback based on an information field within the SCI. In one embodiment, the information field indicates whether HARQ is enabled for PSSCH transmission.

[0010] In some implementations of the methods and apparatus described herein, the UE determines not to initiate another COT before sending HARQ feedback after confirming 1) the SCI indicates that HARQ is enabled for PSSCH transmission, and 2) the PSFCH transmission is within the COT duration indicated by the SCI.

[0011] In some implementations of the methods and apparatus described herein, the SCI includes an indication of whether to use a cyclic prefix extension in conjunction with sending HARQ feedback, and the method includes sending the cyclic prefix extension, wherein the cyclic prefix extension shortens the duration of a guard interval in the same resource pool in which the HARQ feedback is sent.

[0012] In some implementations of the methods and apparatus described herein, the SCI includes an indication indicating whether a listen-before-talk procedure is to be performed before sending the HARQ feedback.

[0013] In some implementations of the methods and apparatus described herein, an identical copy of at least a first portion of the PSFCH transmission is sent immediately after the HARQ feedback is sent on the PSFCH.

[0014] In some implementations of the methods and apparatus described herein, the only transmissions allowed during the COT indicated by the SCI include HARQ feedback and repetitions of HARQ feedback.

[0015] Some implementations of the methods and apparatus described herein may also include a user equipment (UE) for wireless communication, the UE comprising at least one memory and at least one processor, the at least one processor coupled to the at least one memory and configured to enable the UE to receive an SCI allocating resources for a PSSCH transmission, the SCI comprising a field indicating a COT duration, and to send HARQ feedback in a PSFCH transmission during the COT duration without initiating another COT based on the SCI.

[0016] Some implementations of the methods and apparatus described herein may also include a processor for wirelessly communicating with at least one memory and a controller, the controller being coupled to the at least one memory, the processor being configured to cause the controller to receive an SCI allocating resources for a PSSCH transmission, the SCI including a field indicating a COT duration, and to send HARQ feedback in a PSFCH transmission during the COT duration without initiating another COT based on the SCI. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 An example of a wireless communication system supporting channel occupancy sharing for sidelink transmissions in accordance with aspects of the present disclosure is illustrated.

[0018] Figure 2 An example of a system supporting channel occupancy sharing for sidelink transmissions in accordance with aspects of the present disclosure is illustrated.

[0019] Figure 3 An example of a block diagram of a device supporting channel occupancy sharing for sidelink transmissions in accordance with aspects of the present disclosure is illustrated.

[0020] Figures 4 to 6 An example of a time slot for sidelink communications is illustrated.

[0021] Figure 7 is a flow chart of a method of supporting channel occupancy sharing for sidelink transmissions according to aspects of the present disclosure.

[0022] Figure 8 Illustrated is an example of a block diagram of a processor supporting channel occupancy sharing for sidelink feedback channel transmissions in accordance with aspects of the present disclosure. DETAILED DESCRIPTION

[0023] For operation in unlicensed spectrum, specifically in semi-static channel access (operation according to frame-based devices), after the listen-before-talk (LBT) procedure, after a node such as a gNB or UE acquires a shared channel through a successful clear channel assessment (CCA), downlink transmission and uplink transmission are allowed. The procedure for gNB and UE to acquire the channel occupation time (COT) has been specified for both dynamic channel access and semi-static channel access.

[0024] In a traditional cellular topology with a centralized scheduler, a gNB can initiate a COT and can share the COT with one or more UEs, or a UE can initiate a COT and share the COT with a gNB. The sharing of the COT is indicated by a specific field in the downlink control information or the uplink control information.

[0025] For operation in unlicensed spectrum, sidelink transmissions are allowed after a node such as a UE acquires a shared channel through a successful clear channel assessment (CCA) following a listen-before-talk (LBT) procedure. In a sidelink environment, a UE may use a hybrid automatic repeat request (HARQ) protocol for sidelink connections with multiple UEs. The UE may send HARQ feedback information on a physical sidelink feedback channel (PSFCH) for sidelink transmissions, particularly physical sidelink shared channel (PSSCH) transmissions.

[0026] When a receiving UE initiates its own COT for a PSFCH transmission, it is not always guaranteed that the HARQ feedback will be sent at the allocated timing. For example, the LBT process may not be successful. This will ultimately increase the latency of the sidelink transmission and affect its reliability.

[0027] Since COT sharing provides shorter or no channel sensing time required for idle channel assessment, it is beneficial for the UE to utilize COT sharing for transmission of HARQ feedback for PSSCH transmission. The present disclosure proposes a solution for the UE to avoid initiating its own COT for transmission of HARQ feedback on PSFCH. Instead, the COT acquired by the UE for the corresponding PSSCH transmission is shared for PSFCH transmission.

[0028] According to one embodiment, the receiving UE regards the COT obtained by the transmitting UE for the PSSCH transmission as being shared for the transmission of the corresponding HARQ feedback on the PSFCH. For the case where the (multiple) PSFCH symbols in the resource pool overlap with the COT obtained by the transmitting UE that issued the PSSCH transmission to the receiving UE, the receiving UE assumes that the transmitting UE shares the COT with the receiving UE for the transmission of the corresponding PSFCH transmission.

[0029] According to one embodiment, the sidelink control information (SCI) includes two new fields that indicate whether the COT is shared with the receiving UE for transmission of the PSFCH corresponding to the PSSCH associated with the SCI, and whether the reception should use a cyclic prefix (CP) extension to shorten the gap before the PSFCH symbol, such as the gap between the PSSCH symbol and the automatic gain control (AGC) symbol before the PSFCH.

[0030] Since COT sharing allows for shorter or no channel sensing time for clear channel assessment, it is beneficial for a UE to utilize COT sharing for transmission of HARQ feedback for PSSCH transmission.Benefits of embodiments of the present disclosure include improved reliability and more efficient use of time and processing resources.

[0031] Aspects of the present disclosure are described in the context of a wireless communication system. Aspects of the present disclosure are further illustrated and described with reference to device diagrams and flow charts.

[0032] Figure 1 An example of a wireless communication system 100 supporting channel occupancy sharing for sidelink feedback channel transmission according to various aspects of the present disclosure is illustrated. The wireless communication system 100 may include one or more network entities 102, one or more UEs 104, a core network 106, and a packet data network 108. The wireless communication system 100 may support various radio access technologies. In some implementations, the wireless communication system 100 may be a 4G network, such as an LTE network or an advanced LTE (LTE-A) network. In some other implementations, the wireless communication system 100 may be a 5G network, such as an NR network. In other implementations, the wireless communication system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technologies, including the Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20. The wireless communication system 100 may support radio access technologies other than 5G. In addition, the wireless communication system 100 may support technologies such as time division multiple access (TDMA), frequency division multiple access (FDMA), or code division multiple access (CDMA).

[0033] One or more network entities 102 may be dispersed throughout a geographic area to form a wireless communication system 100. One or more of the network entities 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a radio access network (RAN), a base transceiver station, an access point, a NodeB, an eNodeB (eNB), a next generation NodeB (gNB), or other suitable terms. The network entity 102 and the UE 104 may communicate via a communication link 110, which may be a wireless or wired connection. For example, the network entity 102 and the UE 104 may perform wireless communication (e.g., receive signaling, send signaling) over a Uu interface.

[0034] The network entity 102 may provide a geographic coverage area 112 for which the network entity 102 supports services (e.g., voice, video, packet data, messaging, broadcast, etc.) for one or more UEs 104 within the geographic coverage area 112. For example, the network entity 102 and the UE 104 may support wireless communications of signals associated with services (e.g., voice, video, packet data, messaging, broadcast, etc.) according to one or more radio access technologies. In some implementations, the network entity 102 may be mobile, for example, a satellite associated with a non-terrestrial network. In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but different geographic coverage areas 112 may be associated with different network entities 102. The information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0035] One or more UEs 104 may be dispersed throughout the geographic area of ​​the wireless communication system 100. UE 104 may include or may be referred to as a mobile device, a wireless device, a remote device, a remote unit, a handheld device, a subscriber device, or some other suitable term. In some implementations, UE 104 may be referred to as a unit, a station, a terminal, or a client, etc. Additionally or alternatively, UE 104 may be referred to as an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communication (MTC) device, etc. In some implementations, UE 104 may be stationary in the wireless communication system 100. In some other implementations, UE 104 may be mobile in the wireless communication system 100.

[0036] One or more UEs 104 may be devices of different forms or with different capabilities. Figure 1 Some examples of UE 104 are illustrated in FIG. Figure 1As shown, UE 104 can communicate with various types of devices, such as network entity 102, other UEs 104, or network devices (e.g., core network 106, packet data network 108, relay device, integrated access and backhaul (IAB) node, or another network device), such as Figure 1 Additionally or alternatively, the UE 104 can support communications with other network entities 102 or UEs 104 that can act as relays in the wireless communication system 100.

[0037] The UE 104 may also be capable of supporting wireless communications directly with other UEs 104 via a communication link 114. For example, the UE 104 may support wireless communications directly with another UE 104 via a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular V2X deployments, the communication link 114 may be referred to as a sidelink. For example, the UE 104 may support wireless communications directly with another UE 104 via a PC5 interface.

[0038] The network entity 102 may support communication with the core network 106 or with another network entity 102 or both. For example, the network entity 102 may interface with the core network 106 via one or more backhaul links 116 (e.g., via S1, N2, N2 or another network interface). The network entities 102 may communicate with each other via the backhaul links 116 (e.g., via X2, Xn or another network interface). In some implementations, the network entities 102 may communicate directly with each other (e.g., between the network entities 102). In some other implementations, the network entities 102 may communicate with each other or indirectly (e.g., via the core network 106). In some implementations, one or more network entities 102 may include subcomponents, such as access network entities, which may be examples of access node controllers (ANCs). The ANC may communicate with one or more UEs 104 via one or more other access network transport entities (which may be referred to as radio heads, smart radio heads, or transport reception points (TRPs)).

[0039] In some implementations, the network entity 102 may be configured in a decomposed architecture that may be configured to utilize a protocol stack that is physically or logically distributed between two or more network entities 102, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance), or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN)). For example, the network entity 102 may include one or more of a central unit (CU), a distributed unit (DU), a radio unit (RU), a RAN intelligent controller (RIC) (e.g., a near real-time RIC (near RT RIC), a non-real-time RIC (non-RT RIC)), a service management and orchestration (SMO) system, or any combination thereof.

[0040] The RU may also be referred to as a radio head, a smart radio head, a remote radio head (RRH), a remote radio unit (RRU), or a transmission reception point (TRP). In a decomposed RAN architecture, one or more components of the network entity 102 may be collocated, or one or more components of the network entity 102 may be located at distributed locations (e.g., separate physical locations). In some implementations, one or more network entities 102 of the decomposed RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0041] The functional split between CU, DU and RU can be flexible, and different functions can be supported according to the functions performed at the CU, DU or RU (e.g., network layer functions, protocol layer functions, baseband functions, radio frequency functions and any combination thereof). For example, a functional split of a protocol stack can be adopted between the CU and the DU so that the CU can support one or more layers of the protocol stack and the DU can support one or more different layers of the protocol stack. In some implementations, the CU can host upper protocol layer (e.g., Layer 3 (L3), Layer 2 (L2)) functions and signaling (e.g., Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP), Packet Data Convergence Protocol (PDCP)). The CU can be connected to one or more DUs or RUs, and one or more DUs or RUs can host lower protocol layers, such as Layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, media access control (MAC) layer) functions and signaling, and each can be at least partially controlled by the CU 160.

[0042] Additionally or alternatively, a functional split of the protocol stack may be employed between the DU and the RU such that the DU may support one or more layers of the protocol stack and the RU may support one or more different layers of the protocol stack. The DU may support one or more different cells (e.g., via one or more RUs). In some implementations, the functional split between the CU and the DU or between the DU and the RU may be within the protocol layer (e.g., some functions of the protocol layer may be performed by one of the CU, DU, or RU, while other functions of the protocol layer may be performed by different ones of the CU, DU, or RU).

[0043] The CU may be further functionally split into CU control plane (CU-CP) and CU user plane (CU-UP) functions. The CU may be connected to one or more DUs via a medium-range communication link (e.g., F1, F1-c, F1-u), and the DU may be connected to one or more RUs via a fronthaul communication link (e.g., an open fronthaul (FH) interface). In some implementations, the medium-range communication link or the fronthaul communication link may be implemented based on interfaces (e.g., channels) between layers of a protocol stack supported by a corresponding network entity 102 communicating via such a communication link.

[0044] The core network 106 may support user authentication, access authorization, tracking, connection, and other access, routing, or mobility functions. The core network 106 may be an evolved packet core (EPC) or a 5G core (5GC), which may include control plane entities that manage access and mobility (e.g., mobility management entity (MME), access and mobility management function (AMF)), and user plane entities that route packets or interconnections to external networks (e.g., serving gateway (S-GW), packet data network (PDN) gateway (P-GW), or user plane function (UPF)). In some implementations, the control plane entities may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc.) of one or more UEs 104 served by one or more network entities 102 associated with the core network 106.

[0045] The core network 106 may communicate with the packet data network 108 via one or more backhaul links 116 (e.g., via S1, N2, N2, or another network interface). The packet data network 108 may include an application server 118. In some implementations, one or more UEs 104 may communicate with the application server 118. The UE 104 may establish a session (e.g., a protocol data unit (PDU) session, etc.) with the core network 106 via the network entity 102. The core network 106 may use the established session (e.g., the established PDU session) to route traffic (e.g., control information, data, etc.) between the UE 104 and the application server 118. The PDU session may be an example of a logical connection between the UE 104 and the core network 106 (e.g., one or more network functions of the core network 106).

[0046] In the wireless communication system 100, the network entity 102 and the UE 104 may use the resources of the wireless communication system 100 (e.g., time resources (e.g., symbols, time slots, subframes, frames, etc.) or frequency resources (e.g., subcarriers, carriers)) to perform various operations (e.g., wireless communication). In some implementations, the network entity 102 and the UE 104 may support different resource structures. For example, the network entity 102 and the UE 104 may support different frame structures. In some implementations, such as in 4G, the network entity 102 and the UE 104 may support a single frame structure. In some other implementations, such as in 5G and other suitable radio access technologies, the network entity 102 and the UE 104 may support various frame structures (i.e., multiple frame structures). The network entity 102 and the UE 104 may support various frame structures based on one or more digital technologies.

[0047] One or more digital technologies may be supported in the wireless communication system 100, and the digital technologies may include subcarrier spacing and cyclic prefixes. A first digital technology (e.g., μ = 0) may be associated with a first subcarrier spacing (e.g., 15kHz) and a normal cyclic prefix. In some implementations, a first digital technology (e.g., μ = 0) associated with a first subcarrier spacing (e.g., 15kHz) may utilize one slot per subframe. A second digital technology (e.g., μ = 1) may be associated with a second subcarrier spacing (e.g., 30kHz) and a normal cyclic prefix. A third digital technology (e.g., μ = 2) may be associated with a third subcarrier spacing (e.g., 60kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth digital technology (e.g., μ = 3) may be associated with a fourth subcarrier spacing (e.g., 120kHz) and a normal cyclic prefix. A fifth digital technology (e.g., μ = 4) may be associated with a fifth subcarrier spacing (e.g., 240kHz) and a normal cyclic prefix.

[0048] The time intervals of resources (e.g., communication resources) can be organized according to frames (also referred to as radio frames). Each frame can have a duration, for example, a duration of 10 milliseconds (ms). In some implementations, each frame can include multiple subframes. For example, each frame can include 10 subframes, and each subframe can have a duration, for example, a duration of 1 ms. In some implementations, each frame can have the same duration. In some implementations, each subframe of a frame can have the same duration.

[0049] Additionally or alternatively, the time interval of resources (e.g., communication resources) can be organized according to time slots. For example, a subframe may include a certain number (e.g., quantity) of time slots. The number of time slots in each subframe may also depend on one or more digital technologies supported in the wireless communication system 100. For example, a first digital technology, a second digital technology, a third digital technology, a fourth digital technology, and a fifth digital technology (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with corresponding subcarrier spacings of 15kHz, 30kHz, 60kHz, 120kHz, and 240kHz may utilize one time slot per subframe, two time slots per subframe, four time slots per subframe, eight time slots per subframe, and 16 time slots per subframe, respectively. Each time slot may include a certain number (e.g., quantity) of symbols (e.g., OFDM symbols). In some implementations, the number (e.g., quantity) of time slots of a subframe may depend on the digital technology. For a normal cyclic prefix, a time slot may include 14 symbols. For an extended cyclic prefix (e.g., for a 60 kHz subcarrier spacing), a slot may include 12 symbols. For a normal cyclic prefix and an extended cyclic prefix, the relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame may depend on the digital technology. It should be understood that references to a first digital technology (e.g., μ=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

[0050] In the wireless communication system 100, the electromagnetic (EM) spectrum can be divided into various categories, frequency bands, frequency channels, etc. based on frequency or wavelength. For example, the wireless communication system 100 can support one or more operating frequency bands, such as frequency range names FR1 (410 MHz-7.125 GHz), FR2 (24.25 GHz-52.6 GHz), FR3 (7.125 GHz-24.25 GHz), FR4 (52.6 GHz-114.25 GHz), FR4a or FR4-1 (52.6 GHz-71 GHz), and FR5 (114.25 GHz-300 GHz). In some implementations, the network entity 102 and the UE 104 can perform wireless communications on the one or more operating frequency bands. In some implementations, FR1 can be used by the network entity 102 and the UE 104 and other devices or apparatuses for cellular communication services (e.g., control information, data). In some implementations, FR2 can be used by the network entity 102 and the UE 104 and other devices or apparatuses for short-range, high data rate capabilities.

[0051] FR1 may be associated with one or more digital technologies (e.g., at least three digital technologies). For example, FR1 may be associated with a first digital technology (e.g., μ=0) including a subcarrier spacing of 15 kHz; a second digital technology (e.g., μ=1) including a subcarrier spacing of 30 kHz; a third digital technology (e.g., μ=2) including a subcarrier spacing of 60 kHz. FR2 may be associated with one or more digital technologies (e.g., at least 2 digital technologies). For example, FR2 may be associated with a third digital technology (e.g., μ=2) including a subcarrier spacing of 60 kHz; a fourth digital technology (e.g., μ=3) including a subcarrier spacing of 120 kHz.

[0052] Figure 2 An example of a system supporting channel occupancy sharing for sidelink feedback channel transmissions in accordance with aspects of the present disclosure is illustrated.

[0053] Embodiments of the present disclosure relate to sidelink communications between UEs 104 using unlicensed spectrum. Sidelink communications may be facilitated by a base station node 102, such as a gNB. For example, the base station 102 and a transmitting UE 104a may communicate with each other via a communication link 110, and each receiving UE 104b may communicate with the base station 102 via a respective communication link 110. In addition, the transmitting UE 104a may communicate with a nearby receiving UE 104b using sidelink communications 114.

[0054] In one example, base station 102 is a gNB that provides data to a transmitting UE 104a, which in turn broadcasts the data to multiple receiving UEs 104b in an unlicensed spectrum. This can be helpful, for example, when the licensed spectrum is highly occupied, or in other situations where the unlicensed spectrum is a viable or better alternative to the licensed spectrum.

[0055] Figure 3 An example of a block diagram 300 of a device 302 supporting channel occupancy sharing for sidelink transmissions in accordance with various aspects of the present disclosure is illustrated. The device 302 may be an example of a UE 104 as described herein. The device 302 may support wireless communications with one or more network entities 102, UEs 104, or any combination thereof. The device 302 may include components for bidirectional communications, including components for sending and receiving communications (such as a processor 304, a memory 306, a transceiver 308, and an I / O controller 310). These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., a bus).

[0056] The processor 304, the memory 306, the transceiver 308, or various combinations thereof, or various components thereof may be examples of means for performing various aspects of the present disclosure described herein. For example, the processor 304, the memory 306, the transceiver 308, or various combinations thereof, or components thereof may support methods for performing one or more of the operations described herein.

[0057] In some implementations, the processor 304, memory 306, transceiver 308, or various combinations or components thereof may be implemented in hardware (e.g., in a communications management circuit system). The hardware may include a processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof, which is configured to or otherwise supports means for performing the functions described in the present disclosure. In some implementations, the processor 304 and the memory 306 coupled to the processor 304 may be configured to perform one or more functions described herein (e.g., by executing instructions stored in the memory 306 by the processor 304).

[0058] For example, according to examples disclosed herein, processor 304 can support wireless communications at device 302. Processor 304 can be configured to or otherwise support channel occupancy sharing for sidelink feedback channel transmissions.

[0059] The processor 304 may include an intelligent hardware device (e.g., a general purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some implementations, the processor 304 may be configured to operate a memory array using a memory controller. In some other implementations, the memory controller may be integrated into the processor 304. The processor 304 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 306) to cause the device 302 to perform various functions of the present disclosure.

[0060] The memory 306 may include random access memory (RAM) and read-only memory (ROM). The memory 306 may store computer-readable computer executable code, which includes instructions that, when executed by the processor 304, cause the device 302 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as a system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 304, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein. In some implementations, the memory 306 may include a basic I / O system (BIOS), which may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0061] I / O controller 310 can manage input and output signals of device 302. I / O controller 310 can also manage peripheral devices that are not integrated into device 2402. In some implementations, I / O controller 310 can represent a physical connection or port to an external peripheral device. In some implementations, I / O controller 310 can utilize an operating system, such as Or another known operating system. In some implementations, I / O controller 310 can be implemented as part of a processor such as processor M06. In some implementations, a user can interact with device 302 via I / O controller 310 or via hardware components controlled by I / O controller 310.

[0062] In some implementations, the device 302 may include a single antenna 312. However, in some other implementations, the device 302 may have more than one antenna 312 (i.e., multiple antennas), including multiple antenna panels or antenna arrays, which are capable of concurrently sending or receiving multiple wireless transmissions. The transceiver 308 can communicate bidirectionally via one or more antennas 312, wired or wireless links, as described herein. For example, the transceiver 308 can represent a wireless transceiver and can communicate bidirectionally with another wireless transceiver. The transceiver 308 may also include a modem for modulating packets, providing the modulated packets to one or more antennas 312 for transmission, and demodulating packets received from one or more antennas 312.

[0063] For operation in unlicensed spectrum, in particular in semi-static channel access (operation according to Frame-Based Equipment (FBE)), after the Listen Before Talk (LBT) procedure, after a node such as a gNB or UE acquires a shared channel through a successful Clear Channel Assessment (CCA), downlink transmission and uplink transmission are allowed. If the device / network node performing LBT does not detect the presence of other signals in the channel, the channel is considered available for transmission.

[0064] In FBE mode, the network node performs LBT during idle periods, and after acquiring the channel, the network node can communicate during the non-idle time of the fixed frame period duration, called the channel occupation time (COT). In the current specifications and regulations, the idle time is not shorter than 5% of FFP and a maximum value of 100 microseconds. The process of gNB and UE acquiring the channel occupation time (COT) can be used for both dynamic channel access and semi-static channel access.

[0065] Determining ownership of the COT, or determining which device has initiated the COT for UL transmissions, may be performed at both the gNB and the UE to determine 1) whether another UE may issue another UL transmission within the COT, 2) which idle period (gNB's or UE's) should be observed (e.g., UL transmissions are not allowed during the observed idle period), and 3) the energy detection (ED) threshold. The ED threshold may be different, for example, when the gNBs share a UE-COT or a UE-initiated COT; or may be different if the ED threshold is determined based on the UE transmit power and / or the gNB transmit power.

[0066] In a sidelink environment, a UE may use HARQ to or from multiple UE sidelink connections, in which case the UE may send HARQ feedback information on the PSFCH for sidelink transmissions (PSSCH). Since COT sharing allows for shorter or no channel sensing time for clear channel assessment, it is beneficial for the UE to utilize COT sharing for transmission of HARQ feedback for PSSCH transmissions. Currently, COT sharing is not supported on sidelink unlicensed carriers.

[0067] The present disclosure proposes a solution for a UE to avoid initiating its own COT for transmission of HARQ feedback on the PSFCH.

[0068] After the transmitting UE has initiated a COT for sidelink communication in the unlicensed spectrum, the transmitting UE can use the physical sidelink control channel (PSCCH) and PSSCH resources in the occupied channel. In NR, the available sidelink resources include time slots (time resources) allocated for the sidelink and common RBs (frequency resources) within the sidelink bandwidth part (BWP). A subset of the available sidelink resources is configured to be used by several UEs for their sidelink transmissions. This subset of available sidelink resources is called a resource pool (RP). The common resource blocks within the resource pool are called physical resource blocks (PRBs). A resource pool can consist of consecutive PRBs and consecutive or discontinuous time slots that are configured for sidelink transmissions.

[0069] Figure 4 An embodiment of a PSSCH time slot in a sidelink associated with a PSFCH symbol is illustrated. Figure 4 In an embodiment, the last set of time slots in the time domain includes a PSFCH in which HARQ feedback for a previous PSSCH may be provided to the transmitting UE.

[0070] In the case where there are L subchannels in the resource pool and N PSSCH slots are associated with a slot containing PSFCH, N·L subchannels are associated with the PSFCH symbol. In the case where there are M PRBs available for PSFCH in a PSFCH symbol, there are M PRBs available for HARQ feedback for transmissions on N·L subchannels. In the case where M is configured as a multiple of N·L, a different set of PRBs may be associated with HARQ feedback for each subchannel within the PSFCH period.

[0071] A first group of PRBs among the M PRBs available for PSFCH is associated with HARQ feedback for transmissions in the first subchannel in the first time slot. A second group of PRBs is associated with HARQ feedback for transmissions in the first subchannel in the second time slot, and so on. Figure 4As shown, where N=4, L=3, and all PRBs in a PSFCH symbol are available for PSFCH. In this example, HARQ feedback for a transmission at PSSCH x is sent on the PRBs in the corresponding PSFCH symbol, where x=1, ..., 12.

[0072] For a transmission in PSSCH with LPSSCH>1 subchannel, LPSSCH·Mset PRBs may be used for HARQ feedback for the transmission. Figure 4 The diagram shows a transmission in the second time slot (LPSSCH=2) over the first subchannel and the second subchannel. Then, two groups of PRBs in the first subchannel and the second subchannel of the PSFCH symbol may be used for HARQ feedback of the transmission.

[0073] Figure 5 An embodiment of a sidelink (PSCCH / PSSCH) slot with PFSCH symbols is illustrated. Figure 5 The PSFCH in the time slot carries the HARQ feedback from the receiving UE to the transmitting UE. Within the resource pool, the PSFCH resources can be periodically configured with a period of 1, 2 or 4 time slots, so that there is a PSFCH time slot every 1, 2 or 4 time slots in the resource pool. The PSFCH can be sent in one of the last sidelink symbols in the PSCCH / PSSCH time slot, such as Figure 5 As shown in the example in . Before the PSFCH symbol, an AGC symbol is used, which can be a copy of the PSFCH symbol. The symbol after the PSFCH symbol can be used as a guard symbol, as shown in the figure.

[0074] In the resource pool, a set of PRBs available for PSFCH in a PSFCH symbol may be indicated using a bitmap.For transmission of PSFCH, one PRB in a PSFCH symbol may be used, which carries a Zadoff-Chu sequence based on the sequence used for the Physical Uplink Control Channel (PUCCH) in Uu.

[0075] According to one embodiment of the present disclosure, UE 104 considers that the COT obtained by the transmitting UE 104a is shared for transmission of HARQ feedback on the PSFCH. For the case where one or more PSFCH symbols in the resource pool overlap with the COT obtained by the transmitting UE 104a that issues a PSSCH transmission to the receiving UE 104b, the receiving UE 104b determines that the transmitting UE 104a shares the COT with the receiving UE 104b for transmission of at least or only the corresponding PSFCH. The transmitting UE 104a can indicate information about the obtained COT, such as the remaining COT duration, the channel access priority (CAPC) used to initiate the COT, etc. This information can be indicated in the SCI sent to the receiving UE 104b together with the PSSCH.

[0076] Since COT sharing provides shorter or no channel sensing time required for clear channel assessment, it is beneficial for the receiving UE 104b to view the COT as being shared for PSFCH transmission. According to one implementation, the shared COT is only valid for PSFCH transmission, so no further sidelink transmissions from the receiving UE 104b are allowed within the shared COT. In one embodiment, after the PSFCH transmission, the right to use the remaining COT is implicitly returned to the transmitting UE 104a that originally initiated the COT, so that the receiving UE 104b implicitly shares the remaining COT with the transmitting UE 104a.

[0077] In one embodiment, the receiving UE 104b uses CP extension to shorten or fill the gap before the PSFCH symbol. The gap can be the gap between the PSSCH symbol and the AGC symbol before the PSFCH, for example Figure 5 The guard symbol indicated in . Shortening the gap can eliminate the need to perform LBT for PSFCH transmissions in the shared COT. Leaving a symbol gap before the PSFCH / AGC symbol may cause the UE to lose the channel. The length of the CP extension used to fill the gap can be a single symbol of duration 16μs.

[0078] These and other embodiments will now be explained in greater detail with reference to method 700 .

[0079] Figure 7 A flow chart of a method 700 for supporting channel occupancy sharing for sidelink transmissions according to aspects of the present disclosure is illustrated. The operations of the method 700 may be implemented by an apparatus or component thereof as described herein. For example, the operations of the method 700 may be implemented by a device or component thereof as described in reference to Figures 1 to 3 The UE 104 described herein performs. In some implementations, the device may execute a set of instructions to control the functional elements of the device to perform the described functions. Additionally or alternatively, the device may use dedicated hardware to perform various aspects of the described functions.

[0080] At 705, the method may include receiving sidelink control information (SCI). The operations of 705 may be performed according to examples as described herein. In some implementations, aspects of the operations of 705 may be performed by reference to Figure 1 The device is used to perform the above.

[0081] The SCI may be used to signal the slot format, COT duration, available RB set, and search space set group switching within the COT. For example, the SCI may send one or more of a set of slot format indicators, a set of available resource blocks, COT duration, the identity of the entity to which the COT belongs, etc. In one embodiment, the SCI includes one or more indications indicating whether the COT is shared for the purpose of sending HARQ feedback on the PSFCH.

[0082] In embodiments where the transmitting UE 104 has established a COT, the SCI received at 705 may be transmitted in the PSCCH during the COT. The SCI may be received by one or more UEs in an unlicensed spectrum.

[0083] At 710, the method may include extracting information from the received SCI. The operations of 710 may be performed according to examples as described herein. In some implementations, aspects of the operations of 710 may be described by reference to Figure 1 Extracting information may include one or more of decoding the received SCI, storing the SCI in a memory, and processing information within the SCI.

[0084] The information that can be extracted from the received SCI at 710 includes the duration of the COT established by the transmitting UE 104a as described above, and the general information within the SCI. In one embodiment, the receiving UE 104b extracts a new field within the SCI associated with the PSSCH transmission that indicates whether the COT is shared for the corresponding PSFCH. Specifically, the field can indicate that the COT is shared to the receiving UE 104b (which can be the recipient of the PSSCH transmission) for the purpose of HARQ feedback of the PSSCH transmission.

[0085] In another embodiment, the SCI includes two new fields that indicate whether the COT is shared with the receiving UE 104b for transmission of the PSFCH corresponding to the PSSCH associated with the SCI, and whether the receiving UE 104b should use CP extension to shorten the gap before the PSFCH symbol, such as the gap between the PSSCH symbol and the AGC symbol. Therefore, the receiving UE 104b can extract the first field from the SCI indicating whether the COT is shared for transmission on the PSFCH and the second field from the SCI indicating whether CP extension is to be used to fill the gap in the subchannel.

[0086] In one embodiment, the SCI accompanying the PSSCH indicates whether LBT is to be performed by the receiving UE 104b for the corresponding PSFCH transmission, such as HARQ feedback for the PSSCH. In such an embodiment, the receiving UE 104b extracts the LBT indication from the SCI at 710 and performs or does not perform LBT according to the indication value before sending the HARQ feedback.

[0087] In one embodiment, the SCI indicates COT sharing information to a group of receiving UEs. According to one implementation, the SCI is not accompanied by a PSSCH, so the SCI is provided in an SCI-only transmission. In one example, the COT sharing information includes the COT duration. In one embodiment, the COT sharing information indicates whether the receiving UE is to initiate its own COT for a PSFCH transmission, or whether the COT is shared for a PSFCH transmission. In one example, the COT sharing information indicates whether the CP extension should be used to shorten or fill the gap before the PSFCH. In another example, the SCI indicates in the COT sharing information whether the receiving UE 104b is to perform LBT for the PSFCH transmission. In these embodiments, the receiving UE 104b can extract any of this information from the SCI that is not accompanied by the PSSCH.

[0088] At 715, the method may include determining whether the COT is shared. The operations of 715 may be performed according to examples as described herein. In some implementations, aspects of the operations of 715 may be described by reference to Figure 1 The device is used to perform the above.

[0089] After receiving the SCI, at 715, the receiving UE determines whether the transmitting UE 104a shares its COT with the receiving UE 104b for PSFCH transmission. If the receiving UE 104b determines that the transmitting UE 104a does not share its COT, the receiving UE 104b may initiate its own COT and send HARQ feedback for the PSSCH on the PSFCH within the COT. Otherwise, if the receiving UE 104b determines that the COT is shared, the receiving UE 104b sends HARQ feedback on the PSFCH within the shared COT.

[0090] In one embodiment, the receiving UE 104b is configured to determine that the COT is shared at 715 when it is determined that the PSFCH is available for providing HARQ feedback within the COT duration. In another embodiment, the receiving UE 104b determines whether the COT is shared based on information extracted from the SCI at 710. For example, the receiving UE 104b may determine whether the COT initiated by the transmitting UE 104a is shared with the receiving UE 104b for transmission in the PSFCH corresponding to the PSSCH transmission from the transmitting UE 104a based on a field within the SCI accompanying the PSSCH.

[0091] According to one embodiment, the receiving UE 104b determines whether the COT is assumed to be shared based on a field within the SCI indicating whether HARQ is enabled (e.g., a "HARQ Enabled" field), and therefore does not initiate its own COT for transmission of the PSFCH. Specifically, when the SCI indicates that HARQ is enabled for the corresponding PSSCH transmission, the receiving UE 104b considers that the COT is shared by the transmitting UE 104a for PSFCH transmission. Initiating a COT generally involves sensing within a predetermined amount of sensing time before transmission is allowed, while initiating a PSFCH transmission in a shared COT may not involve such sensing, or may involve only a small portion of the sensing time required to initiate a COT.

[0092] At 720, the method may include sending HARQ or SSB without initiating another COT. The operations of 720 may be performed according to examples as described herein. In some implementations, aspects of the operations of 720 may be described with reference to Figure 1 The device is used to perform the above.

[0093] In one embodiment, as described above, one or more receiving UEs 104b may send HARQ feedback within the COT established by the transmitting UE 104a in the unlicensed spectrum without initiating another COT. That is, the receiving UE 104b may also send HARQ feedback within the COT established by the transmitting UE without establishing a COT for itself or establishing a second COT.

[0094] In one embodiment, one or more receiving UEs 104b transmit a sidelink synchronization signal block (S-SSB) within a COT established by the transmitting UE 104a without initiating another COT.

[0095] Synchronization information can be sent by SyncRef UE 104 in the sidelink to extend the synchronization coverage of the synchronization source and enable nearby UEs to have the same sidelink timing reference. This allows sidelink communication to and from the SyncRef UE and sidelink communication between nearby UEs. The sidelink synchronization information can be carried in a sidelink synchronization signal block (S-SSB) with physical sidelink broadcast channel (PSBCH), sidelink primary synchronization signal (S-PSS) and sidelink secondary synchronization signal (S-SSS) symbols. The S-SSB can occupy one time slot. For normal CP or extended CP, PSBCH, S-PSSS and S-SSS can be carried in the first 13 or 11 symbols of the S-SSB time slot, respectively.

[0096] Figure 6 An example of an S-SSB slot for a normal CP is depicted in FIG, where the last symbol is used as a guard symbol. Since a typical S-SSB is not frequency multiplexed with any other sidelink physical channel within the sidelink bandwidth part (BWP), the S-SSB is not sent in a slot in the resource pool. In the frequency domain, the S-SSB can span 11 common RBs within the sidelink BWP. Since an RB has 12 subcarriers, the SSSB bandwidth spans 11×12=132 subcarriers. The frequency position of the S-SSB is typically configured within the sidelink BWP.

[0097] In one embodiment, the sidelink UE 104 transmitting the S-SSB considers the COT acquired by some other UE 104 to be shared for transmission of the S-SSB. For the case where the reception of an S-SSB by the sidelink UE 104 from the SyncRef UE falls within the COT acquired by the sidelink UE 104, the sidelink UE 104 may implicitly share the COT with the SyncRef UE for transmission of the SL-SSB.

[0098] In such an embodiment, the sidelink UE 104 may indicate information about the acquired COT to the SyncRef UE 104 within the SCI, such as the remaining COT duration, the CAPC used to initiate the COT, etc. At 710, the receiving UE 104b may extract the information from the SCI and determine at 715 that the COT is shared based on the extracted information.

[0099] Since COT sharing allows for shorter or no channel sensing time for clear channel assessment, it is beneficial for UE 104 to consider the COT as being shared for S-SSB transmissions. According to one implementation, the shared COT is only valid for S-SSB transmissions, so no further sidelink transmissions from the SyncRef UE 104 are allowed within the shared COT. In one embodiment, after the S-SSB transmission, the right to use the remaining COT is implicitly returned to the device that originally initiated the COT (the sending UE 104a), so that the SyncRef UE 104 implicitly shares the remaining COT back to the sidelink UE 104.

[0100] At 725, the method may include sending a cyclic prefix. The operations of 725 may be performed according to examples as described herein. In some implementations, aspects of the operations of 725 may be described with reference to Figure 1 The device is used to perform the above.

[0101] In one example, the receiving UE uses CP extension to shorten the gap before and / or after the PSFCH symbol. Figure 5 , these gaps correspond to the guard intervals before and after the PSFCH symbols. Sending the CP at 725 may be performed when the SCI information extracted at 710 indicates that HARQ is enabled for the corresponding PSSCH transmission, or for any condition in which the receiving UE 104b determines at 715 that the COT established by the transmitting UE 104a is shared.

[0102] At 730, the method may include sending a copy of at least a portion of the information sent in the PSFCH. The operations of 730 may be performed according to examples as described herein. In some implementations, aspects of the operations of 730 may be described by reference to Figure 1 The device is used to perform the above.

[0103] In one embodiment, UE 104 appends an identical copy of at least the first portion of the PSFCH symbol after the PSFCH symbol. According to one implementation, UE 104 is a sidelink receiving UE 104b that transmits the PSFCH in response to receiving the PSSCH from the transmitting UE 104a. In order to shorten the gap between the PSFCH and the next PSCCH / PSSCH symbol or the AGC symbol before the next PSCCH symbol, the receiving UE 104b extends the PSFCH transmission to not lose the channel. Shortening the gap can eliminate the need to perform LBT for the PSCCH / PSSCH transmission in the shared COT.

[0104] In one example, an identical copy of the first portion of the PSFCH symbol is used to partially or completely fill a symbol gap. The length of the copy extension can be a single symbol duration or a single symbol duration minus 16 μs. According to one embodiment, the UE 104 is configured to extend the PSFCH as described above to shorten the gap after the PSFCH symbol. In one example, the SCI scheduling the PSSCH transmission indicates whether the receiving UE 104b should extend the PSFCH transmission, such as by appending an identical copy of the first portion of the PSFCH after the PSFCH symbol. This information can be extracted from the SCI at 710.

[0105] As described above, the embodiments of the present disclosure support the following novel features.

[0106] When a PSFCH symbol is in an RP that overlaps with the COT obtained by the transmitting UE 104a transmitting the PSSCH, the receiving UE 104b implicitly assumes that the COT is shared by the transmitting UE 104a or the PSFCH transmission. The gap before the PSFCH symbol can be filled with CP extension to shorten the gap, and whether CP extension is to be used for PSFCH transmission can be configured for the resource pool.

[0107] The SCI accompanying the PSSCH indicates whether the COT is shared for the PSFCH.If HARQ is enabled for PSSCH transmission, the receiving UE 104b does not initiate its own COT for PSFCH transmission.

[0108] A new explicit field in the SCI indicates COT sharing for PSFCH.Another new explicit field in the SCI indicates the use of CP extension for the gap before PSFCH.

[0109] For sidelink transmissions, the SCI indicates whether the receiving UE 104b initiates its own COT or shares the COT of the transmitting UE 104a, and the corresponding LBT scheme (Cat-1 or Cat-2 with appropriate CP extension) for the PSFCH.

[0110] In one implementation, only SCI is used to indicate COT sharing, and PSSCH is not present.

[0111] In one implementation, the SCI indicates that LBT is not performed prior to PSFCH transmission.

[0112] In one implementation, when the S-SSB falls within the acquired COT of the UE receiving the S-SSB, the SyncRef UE 104 implicitly assumes that the COT is shared for S-SSB transmission.

[0113] It should be noted that the methods described herein describe possible implementations, and that the operations and steps may be rearranged or otherwise modified, and other implementations are possible. Furthermore, aspects from two or more methods may be combined.

[0114] The various illustrative blocks and components described in conjunction with the disclosure herein may be implemented or executed with a general purpose processor, DSP, ASIC, CPU, 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 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, multiple microprocessors, one or more microprocessors in combination with a DSP core, or any other such configuration).

[0115] Figure 8 An example of a processor 800 that supports channel occupancy sharing for sidelink transmissions in accordance with various aspects of the present disclosure is illustrated. The processor 800 may be an example of a processor configured to perform various operations in accordance with the examples described herein. The processor 800 may include a controller 802 configured to perform various operations in accordance with the examples described herein. The processor 800 may optionally include at least one memory 804, such as an L1 / L2 / L3 cache. Additionally or alternatively, the processor 800 may optionally include one or more arithmetic logic units (ALUs) 800. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., a bus).

[0116] The processor 800 may be a processor chipset and include a protocol stack (e.g., a software stack) that is executed by the processor chipset to perform various operations (e.g., receive, obtain, retrieve, send, output, forward, store, determine, identify, access, write, read) according to the examples described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., processor 800)), or other memory (e.g., random access memory (RAM), read-only memory (ROM), dynamic RAM (DRAM), synchronous dynamic RAM (SDRAM), static RAM (SRAM), ferroelectric RAM (FeRAM), magnetic RAM (MRAM), resistive RAM (RRAM), flash memory, phase change memory (PCM), etc.).

[0117] The controller 802 may be configured to manage and coordinate various operations (e.g., signaling, receiving, acquiring, retrieving, sending, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 800 so that the processor 800 supports various operations according to the examples described herein. For example, the controller 802 may operate as a control unit of the processor 800 to generate control signals for managing the operation of various components of the processor 800. These control signals include enabling or disabling functional units, selecting data paths, initiating memory accesses, and coordinating operation timing.

[0118] The controller 802 may be configured to retrieve (e.g., acquire, retrieve, receive) instructions from the memory 804 and determine (multiple) subsequent instructions to be executed so that the processor 800 supports various operations according to the examples described herein. The controller 802 may be configured to track the memory address of the instructions associated with the memory 804. The controller 802 may be configured to decode the instructions to determine the operations to be performed and the operands involved. For example, the controller 802 may be configured to interpret the instructions and determine control signals to be output to other components of the processor 800 so that the processor 800 supports various operations according to the examples described herein. Additionally or alternatively, the controller 802 may be configured to manage the data flow within the processor 800. The controller 802 may be configured to control data transfer between registers, arithmetic logic units (ALUs), and other functional units of the processor 800.

[0119] The memory 804 may include one or more caches (e.g., memory local to or included in the processor 800) or other memory (such as RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc.). In some implementations, the memory 804 may reside within or on a processor chipset (e.g., local to the processor 800). In some other implementations, the memory 804 may reside external to the processor chipset (e.g., remote from the processor 800).

[0120] The memory 804 may store computer-readable, computer-executable code, including instructions that, when executed by the processor 800, cause the processor 800 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium, such as a system memory or another type of memory. The controller 802 and / or the processor 800 may be configured to execute computer-readable instructions stored in the memory 804 so that the processor 800 performs various functions. For example, the processor 800 and / or the controller 802 may be coupled to or coupled to the memory 804, and the processor 800, the controller 802, and the memory 804 may be configured to perform various functions described herein. In some examples, the processor 800 may include multiple processors, and the memory 804 may include multiple memories. One or more of the multiple processors may be coupled to one or more of the multiple memories, which may be individually or collectively configured to perform various functions herein.

[0121] According to the examples described herein, one or more ALUs 800 may be configured to support various operations. In some implementations, one or more ALUs 800 may reside in or on a processor chipset (e.g., processor 800). In some other implementations, one or more ALUs 800 may reside outside a processor chipset (e.g., processor 800). One or more ALUs 800 may perform one or more calculations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 800 may receive input operands and an opcode that determines the operation to be performed. One or more ALUs 800 may be configured with various logic and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate data according to the operation. Additionally or alternatively, one or more ALUs 800 may support logic operations such as AND, OR, XOR, NOR, and NAND, so that one or more ALUs 800 may process conditional operations, comparisons, and bit operations.

[0122] According to examples disclosed herein, the processor 800 may support wireless communications.The processor 800 may be configured or operable to support components for channel occupancy sharing for sidelink transmissions.

[0123] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or sent via a computer-readable medium as one or more instructions or codes. Other examples and implementations are within the scope of this disclosure and the appended claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hard wiring, or any combination of these. Features that implement the functions may also be physically located in various locations, including being distributed so that portions of the functions are implemented in different physical locations.

[0124] Computer-readable media include both non-transient computer storage media and communication media, and communication media include any medium that facilitates the transmission of computer programs from one place to another. Non-transient storage media can be any available medium that can be accessed by a general or special-purpose computer. As an example and not limitation, non-transient computer-readable media can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage, disk storage or other magnetic storage devices, or can be used to carry or store desired program code devices in the form of instructions or data structures and can be accessed by a general or special-purpose computer, or any other non-transient medium of a general or special-purpose processor.

[0125] Any connection may be appropriately referred to as a computer-readable medium. For example, if the software is sent from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technology (such as infrared, radio, and microwave), the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technology (such as infrared, radio, and microwave) is included in the definition of computer-readable medium. Disks and optical disks as used herein include CDs, laser disks, optical disks, digital versatile disks (DVDs), floppy disks, and Blu-ray disks, wherein disks typically reproduce data magnetically, and optical disks reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

[0126] As used herein, including in the claims, "or" used in a list of items (e.g., a list of items beginning with a phrase such as "at least one of" or "one or more of" or "one or both of") means an inclusive list, so that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (e.g., A and B and C). In addition, as used herein, the phrase "based on" should not be interpreted as a reference to a closed set of conditions. For example, an example step described as "based on condition A" may be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "based at least in part on." In addition, as used herein, including in the claims, a "set" may include one or more elements.

[0127] When referring to a network entity, the terms "send," "receive," or "transmit" may refer to any part of a network entity of a RAN (e.g., base station, CU, DU, RU) that communicates with another device (e.g., directly or via one or more other network entities).

[0128] The descriptions described herein in conjunction with the accompanying drawings describe example configurations and do not represent all examples that may be implemented or within the scope of the claims. The term "example" as used herein means "used as an example, instance, or illustration," rather than "preferred" or "better than other examples." The detailed description includes specific details to facilitate understanding of the described techniques. However, these techniques may be practiced without these specific details. In some cases, known structures and devices are shown in block diagram form to avoid confusing the concepts of the described examples.

[0129] The description herein is provided to enable one of ordinary skill in the art to make or use the present disclosure. Various modifications to the present disclosure will be clear to one of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Therefore, the present disclosure is not limited to the examples and designs described herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A user equipment (UE) for wireless communication, comprising: at least one memory; as well as at least one processor coupled to the at least one memory and configured to cause the UE to: receiving sidelink control information (SCI) allocating resources for a physical sidelink shared channel (PSSCH) transmission, the SCI including a field indicating a channel occupancy time (COT) duration; and A hybrid automatic repeat request (HARQ) feedback is sent in a physical sidelink feedback channel (PSFCH) transmission within the COT duration without initiating another COT based on the SCI.

2. The UE of claim 1, wherein the at least one processor is further configured to cause the UE to extract the COT duration from the SCI, and When the PSFCH transmission falls within the COT duration extracted from the SCI, the HARQ feedback is sent without initiating another COT.

3. The UE according to claim 1, wherein the at least one processor is configured to cause the UE to determine the COT duration indicated by the SCI to be shared for the transmission of the HARQ feedback on the PSFCH. 4 . The UE of claim 1 , wherein the at least one processor is further configured to cause the UE to determine whether to initiate another COT before sending the HARQ feedback based on an information field within the SCI. 5 . The UE of claim 4 , wherein the information field indicates whether HARQ is enabled for the PSSCH transmission.

6. The UE of claim 5, wherein the at least one processor is further configured to cause the UE to determine not to initiate another COT before sending the HARQ feedback after confirming that 1) the SCI indicates that HARQ is enabled for the PSSCH transmission, and 2) the PSFCH transmission is within the COT duration indicated by the SCI. 7 . The UE of claim 1 , wherein the SCI indicates whether cyclic prefix extension is to be used in conjunction with sending the HARQ feedback.

8. The UE of claim 7, wherein the at least one processor is further configured to cause the UE to send the cyclic prefix extension during a guard interval in a same resource pool in which the HARQ feedback is sent. 9 . The UE of claim 1 , wherein the SCI indicates whether a listen-before-talk procedure is to be performed before sending the HARQ feedback.

10. The UE of claim 1, wherein the at least one processor is further configured to cause the UE to: Immediately after sending the HARQ feedback on the PSFCH, an identical copy of at least a first portion of the PSFCH transmission is sent.

11. The UE of claim 1, wherein the only transmissions allowed by the UE during the COT indicated by the SCI include the HARQ feedback and a repetition of the HARQ feedback.

12. A processor for wireless communication, comprising: at least one memory; as well as a controller coupled to the at least one memory and configured such that the controller: receiving sidelink control information (SCI) allocating resources for a physical sidelink shared channel (PSSCH) transmission, the SCI including a field indicating a channel occupancy time (COT) duration; and A hybrid automatic repeat request (HARQ) feedback is sent in a physical sidelink feedback channel (PSFCH) transmission within the COT duration without initiating another COT based on the SCI.

13. The processor of claim 12, wherein the controller is further configured such that the controller extracts the COT duration from the SCI, and When the PSFCH transmission falls within the COT duration extracted from the SCI, the HARQ feedback is sent without initiating another COT.

14. The processor of claim 12, wherein the controller is further configured such that the controller determines the COT duration indicated by the SCI to be shared for the transmission of the HARQ feedback on the PSFCH.

15. The processor of claim 12, wherein the controller is further configured such that the controller determines whether to initiate another COT before sending the HARQ feedback based on an information field within the SCI.

16. The processor of claim 15, wherein the information field indicates whether HARQ is enabled for the PSSCH transmission.

17. The processor of claim 16, wherein the controller is further configured such that the controller determines not to initiate another COT before sending the HARQ feedback after confirming 1) that the SCI indicates that HARQ is enabled for the PSSCH transmission, and 2) that the PSFCH transmission is within the COT duration indicated by the SCI.

18. The processor of claim 12, wherein the SCI indicates whether cyclic prefix extension is to be used in conjunction with sending the HARQ feedback.

19. The processor of claim 18, wherein the controller is further configured to cause the controller to send the cyclic prefix extension during a guard interval in a same resource pool in which the HARQ feedback is sent.

20. A method performed by a user equipment (UE), the method comprising: receiving sidelink control information (SCI) allocating resources for a physical sidelink shared channel (PSSCH) transmission, the SCI including a field indicating a first channel occupancy time (COT) duration of a COT; and A hybrid automatic repeat request (HARQ) feedback is sent in a physical sidelink feedback channel (PSFCH) transmission within the COT duration without initiating another COT based on the SCI.

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