Method and apparatus for multi-channel access over a sidelink

Abstract

Aspects of the present disclosure relate to methods and apparatus for multi-channel access over a sidelink (SL). In accordance with an embodiment of the present disclosure, a user equipment (UE) may include: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the UE to: select a set of channels for transmission through an SL, where the transmission is one of: a sidelink synchronization signal block transmission, an SL transmission, or a physical sidelink feedback channel transmission; and determining availability of each channel in the set of channels by performing a type independent multi-channel access procedure or a type dependent multi-channel access procedure on the set of channels for the transmission.

Description

Technical Field

[0001] This disclosure relates to wireless communication, and more specifically, to methods and apparatus for multi-channel access via sidelink (SL). Background Technology

[0002] A wireless communication system may include one or more network communication devices, such as a base station (BS), which can support wireless communication with one or more user communication devices (which may also be referred to as user equipment (UE) or other suitable terms). The wireless communication system can support wireless communication with one or more user communication devices by utilizing the resources of the wireless communication system (e.g., time resources (e.g., symbols, time slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers, or the like). Furthermore, the wireless communication system can 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)). Summary of the Invention

[0003] The article “a” preceding an element is unrestricted and should be understood to refer to “at least one” or “one or more” of these elements. As used herein, the terms “a,” “at least one,” “one or more,” and “at least one of one or more” are interchangeable. As used herein (including in the claims), the word “or” used in a list of items (e.g., a list of items beginning with phrases such as “at least one of…”, “one or more of…”, or “one or both of…”) indicates an inclusive list, such that (e.g.) a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Furthermore, as used herein, the phrases “based on” and “according to” should not be construed as referring to a closed set of conditions. For example, without departing from the scope of this disclosure, an exemplary step described as “based on condition A” may be based on both condition A and condition B. In other words, as used herein, the phrase “based on” should be interpreted in the same manner as the phrase “at least partially based on.” Furthermore, as used herein (included in the claims), a “group” may comprise one or more elements.

[0004] Some embodiments of the methods and apparatus described herein may include a UE for wireless communication. The UE may include: at least one memory; and at least one processor coupled to the at least one memory and configured such that the UE: selects a set of channels for a transmission via a SL, wherein the transmission is one of: a Side Link Synchronization Block (S-SSB) transmission, an SL transmission, or a Physical Side Link Feedback Channel (PSFCH) transmission; and determines the availability of each channel within the set of channels by performing a type-independent or type-dependent multichannel access procedure on the set of channels for the transmission.

[0005] In some implementations of the UE described herein, in the type-independent multichannel access procedure: a channel access procedure is performed independently for each channel within the set of channels; and the channel access type on each channel within the set of channels is determined based on whether the channel is within a Channel Occupied Time (COT) or whether the channel is within a COT shared with the UE for performing the transmission.

[0006] In some implementations of the UE described herein, in the type-dependent multichannel access procedure: if at least one channel in the group of channels is outside the COT, a Type 1 dynamic channel access procedure is performed on the first channel in the at least one channel, and a Type 2 dynamic channel access procedure is performed on each of the remaining channels in the group of channels other than the first channel; or if all channels in the group of channels are within the COT, a Type 2 dynamic channel access procedure is performed independently on each channel in the group of channels.

[0007] In some implementations of the UE described herein, in the case of S-SSB transmission, in order to select the set of channels, the at least one processor is configured to cause the UE to: randomly select a channel within a frequency range; preferentially select an anchor channel; or, in the case of the type-dependent multichannel access procedure, preferentially select at least one channel other than COT.

[0008] In some implementations of the UE described herein, in order to perform the type-independent multichannel access procedure for S-SSB transmission, the at least one processor is configured to cause the UE to: individually determine the channel access type on each channel based on whether the target S-SSB timing on each channel in the set of channels is within the COT; and perform a channel access procedure for each channel based on the channel access type individually determined for each channel in the set of channels.

[0009] In some embodiments of the UE described herein, when the transmission is an S-SSB transmission, the at least one processor is further configured to cause the UE to: select the anchor channel to perform the S-SSB transmission if the anchor channel within the set of channels is determined to be available; or, if it is determined that no anchor channel is available: randomly select a channel from all available channels within the set of channels to perform the S-SSB transmission; randomly select a channel from at least one available channel within the set of channels and within the COT to perform the S-SSB transmission; select all available channels within the set of channels to perform the S-SSB transmission; select all available channels within the set of channels and within the COT to perform the S-SSB transmission; or select a channel from at least one channel within the set of channels and within the COT to perform the S-SSB transmission based on the Channel Access Priority Class (CAPC) corresponding to the COT.

[0010] In some implementations of the UE described herein, when performing the type-independent multichannel access procedure for an SL transmission, in order to select the set of channels, the at least one processor is configured such that the UE: at least when the SL transmission is intended for a UE to initiate the COT, preferentially selects channels within the COT shared with the UE.

[0011] In some implementations of the UE described herein, the remaining COT duration of the COT satisfies the UE's transmission requirements.

[0012] In some implementations of the UE described herein, in order to perform the type-independent multichannel access procedure for an SL transmission, the at least one processor is configured to cause the UE to: individually determine the channel access type on the channel based on whether each channel in the set of channels is within a COT shared by the UE for performing at least one SL transmission and whether the SL transmission is at least intended for a UE to initiate the COT; and perform a channel access procedure for each channel based on the channel access type individually determined for each channel in the set of channels.

[0013] In some embodiments of the UE described herein, when the transmission is an SL transmission, the at least one processor is further configured to cause the UE to: select all channels determined to be available to perform the SL transmission.

[0014] In some implementations of the UE described herein, in the case that the transmission is a PSFCH transmission, in order to select the set of channels, the at least one processor is configured to cause the UE to: select its PSFCH resources corresponding to the channels to which the UE transmits SL transmissions with Hybrid Automatic Repeat Request (HARQ) feedback.

[0015] In some implementations of the UE described herein, in order to perform the type-independent multichannel access procedure for a PSFCH transmission, the at least one processor is configured to cause the UE to: individually determine the channel access type on the channel based on whether each channel in the set of channels is within a COT shared by the UE for performing PSFCH transmissions and whether at least one of the PSFCH transmissions is intended for a UE to initiate the COT; and perform a channel access procedure for each channel based on the channel access type individually determined for each channel in the set of channels.

[0016] In some implementations of the UE described herein, when the transmission is a PSFCH transmission, the at least one processor is further configured to cause the UE to: select all channels determined to be available to perform the PSFCH transmission; or, if the UE is unable to transmit PSFCH on all channels determined to be available, discard the PSFCH transmission according to the priority of the corresponding SL transmission.

[0017] In some implementations of the UE described herein, in order to perform the type-dependent multichannel access procedure for S-SSB transmission, the at least one processor is configured such that the UE: if at least one channel in the set of channels is outside the COT, selects a first channel in the at least one channel; performs a Type 1 dynamic channel access procedure on the first channel to determine whether an S-SSB opportunity in the first channel is available for S-SSB transmission; and performs a Type 2 dynamic channel access procedure on each of the remaining channels in the set of channels other than the first channel before the start point of the S-SSB opportunity in the first channel; or, if all channels in the set of channels are within the COT, independently performs a Type 2 dynamic channel access procedure on each channel in the set of channels.

[0018] In some implementations of the UE described herein, when performing the type-dependent multichannel access procedure for SL transmission, in order to select the set of channels, the at least one processor is configured to cause the UE to preferentially select at least one channel other than COT.

[0019] In some embodiments of the UE described herein, in order to perform the type-dependent multichannel access procedure for SL transmission, the at least one processor is configured such that the UE: when at least one channel in the set of channels is outside the COT: selects a first channel in the at least one channel; performs a Type 1 dynamic channel access procedure on the first channel; and performs a Type 2 dynamic channel access procedure on each of the remaining channels in the set of channels other than the first channel before the SL transmission on the first channel; or when all channels in the set of channels are within the COT, independently performs a Type 2 dynamic channel access procedure on each channel in the set of channels.

[0020] In some implementations of the UE described herein, when performing the type-dependent multichannel access procedure for SL transmission, the at least one processor is further configured to cause the UE to: determine whether to perform the SL transmission on the channel if the channel is determined to be available within the COT, based on the remaining COT duration of the COT.

[0021] In some implementations of the UE described herein, in order to perform the type-dependent multichannel access procedure for PSFCH transmission, the at least one processor is configured such that the UE: if at least one channel in the set of channels is outside the COT, selects a first channel in the at least one channel; performs a Type 1 dynamic channel access procedure on the first channel to determine whether a PSFCH timing in the first channel is available for PSFCH transmission; and performs a Type 2 dynamic channel access procedure on each of the remaining channels in the set of channels other than the first channel before the start point of the PSFCH timing in the first channel; or, if all channels in the set of channels are within the COT, independently performs a Type 2 dynamic channel access procedure on each channel in the set of channels.

[0022] In some embodiments of the UE described herein, the at least one processor is further configured such that, for a channel with a subcarrier spacing (SCS) of 60 kHz, if the S-SSB timing is within the COT, the UE reserves two symbols prior to the S-SSB timing for performing the channel access procedure.

[0023] Some embodiments of the methods and apparatus described herein may include a processor for wireless communication. The processor may include: at least one controller coupled to at least one memory and configured to: select a set of channels for a transmission via SL, wherein the transmission is one of: S-SSB transmission, SL transmission, or PSFCH transmission; and determine the availability of each channel within the set of channels by performing a type-independent or type-dependent multichannel access procedure on the set of channels for the transmission.

[0024] Some embodiments of the methods and apparatus described herein may include a BS for wireless communication. The BS may include: at least one memory; and at least one processor coupled to the at least one memory and configured such that the BS: transmits configuration information to a UE for multi-channel access via a SL, wherein the configuration information indicates: a CAPC threshold for enabling the UE to select a channel to perform S-SSB transmission; or a COT duration threshold for enabling the UE to determine whether to perform a sidelink transmission on the channel.

[0025] In some embodiments of the BS described herein, the at least one processor is configured to cause the BS to transmit the configuration information via at least one of the following: Master Information Block (MIB) messages, System Information Block (SIB) messages, Radio Resource Control (RRC) signaling, Medium Access Control (MAC) control element (CE), or Downlink Control Information (DCI).

[0026] Some embodiments of the methods and apparatus described herein may include a method performed by a UE. The method may include: selecting a set of channels for a transmission via an SL, wherein the transmission is one of: an S-SSB transmission, an SL transmission, or a PSFCH transmission; and determining the availability of each channel within the set of channels by performing a type-independent multichannel access procedure or a type-dependent multichannel access procedure on the set of channels used for the transmission.

[0027] Some embodiments of the methods and devices described herein may include a method performed by a BS. The method may include: transmitting configuration information to a UE for multi-channel access via a SL, wherein the configuration information indicates: a CAPC threshold for enabling the UE to select a channel to perform S-SSB transmission; or a COT duration threshold for enabling the UE to determine whether to perform sidelink transmission on a channel. Attached Figure Description

[0028] To illustrate the advantages and features of this application, the description of the application is presented with reference to specific embodiments of the application illustrated in the accompanying drawings. These drawings depict only exemplary embodiments of the application and should therefore not be considered as limiting its scope.

[0029] Figure 1 Examples of wireless communication systems according to aspects of this disclosure are described.

[0030] Figure 2A This describes an exemplary S-SSB time slot based on aspects of this disclosure.

[0031] Figure 2B This illustrates an exemplary distribution of S-SSB timings in the time domain according to aspects of this disclosure.

[0032] Figure 2C This illustrates another exemplary distribution of S-SSB timing in the time domain according to aspects of this disclosure.

[0033] Figure 3 A flowchart illustrating an exemplary method performed by a UE according to aspects of this disclosure.

[0034] Figure 4 This describes exemplary S-SSB timing and COT location for sidelink transmission in a channel, according to aspects of this disclosure.

[0035] Figure 5 Examples of UEs based on aspects of this disclosure are described.

[0036] Figure 6 Examples of processors according to aspects of this disclosure are described.

[0037] Figure 7 Examples of BS based on aspects of this disclosure are described. Detailed Implementation

[0038] The detailed description of the accompanying drawings is intended to illustrate preferred embodiments of the present application and is not intended to represent the only form in which the present application can be practiced. It should be understood that the same or equivalent functionality may be accomplished through different embodiments that are intended to be covered within the spirit and scope of the present application.

[0039] Although operations are depicted in a specific order in the diagram, those skilled in the art will readily recognize that such operations do not necessarily need to be performed in the specific order shown, or in a sequential manner, or that all the described operations need to be performed to achieve the desired result; sometimes, one or more operations can be skipped. Furthermore, the diagram may schematically depict one or more instance processes in the form of a flowchart. However, other operations not depicted may be incorporated into the schematically illustrated instance processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the illustrated operations. In some cases, multitasking and parallel processing can be advantageous.

[0040] Reference will now be made in detail to some embodiments of this application, examples of which are illustrated in the accompanying drawings. To facilitate understanding, embodiments are provided under specific network architectures and new service scenarios (e.g., 3GPP Long Term Evolution (LTE) and LTE Advanced, 3GPP 5G New Radio (NR), 5G Advanced, 6G, etc.). It has been considered that all embodiments in this application are applicable to similar technical problems as network architectures and new service scenarios evolve; furthermore, the terminology cited in this application may be changed without affecting the principles of this application.

[0041] The aspects of this disclosure are described in the context of wireless communication systems.

[0042] Figure 1 This describes an example of a wireless communication system 100 according to aspects of this disclosure. The wireless communication system 100 may include one or more network equipment (NEs) (e.g., BSs) 102, one or more UEs 104, and a core network (CN) 106. The wireless communication system 100 may support various radio access technologies. In some embodiments, the wireless communication system 100 may be a 4G network, such as an LTE network or an LTE-A network. In some other embodiments, the wireless communication system 100 may be an NR network, such as a 5G network, a 5G-A network, or a 5G Ultra Wideband (5G-UWB) network. In other embodiments, the wireless communication system 100 may be a combination of 4G and 5G networks or other suitable radio access technologies, including IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), and IEEE 802.20. The wireless communication system 100 may support radio access technologies beyond 5G, such as 6G. In addition, the wireless communication system 100 can support technologies such as Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), or Code Division Multiple Access (CDMA).

[0043] One or more NEs 102 may be distributed throughout a geographic area to form a wireless communication system 100. One or more of the NEs 102 described herein may be, include, or be referred to as a network node, base station, network element, network function, network entity, wireless access network (RAN), NodeB, eNodeB (eNB), next-generation NodeB (gNB), or other suitable terms. NEs 102 and UEs 104 may communicate via a communication link, which may be wireless or wired. For example, NEs 102 and UEs 104 may perform wireless communication (e.g., receiving signaling, transmitting signaling) via a Uu interface.

[0044] NE 102 can provide a geographic coverage area for which NE 102 can support services for one or more UE 104s within the geographic coverage area. For example, NE 102 and UE 104 can support wireless communication of signals associated with services (e.g., voice, video, packet data, messaging, broadcasting, etc.) using one or more radio access technologies. In some embodiments, NE 102 can be mobile, such as a satellite associated with a non-terrestrial network (NTN). In some embodiments, different geographic coverage areas associated with the same or different radio access technologies may overlap, but different geographic coverage areas may be associated with different NE 102s.

[0045] One or more UEs 104 may be distributed throughout the geographic area of ​​the wireless communication system 100. UE 104 may include or be referred to as a remote unit, mobile device, wireless device, remote device, subscriber device, transmitter device, receiver device, or some other suitable term. In some embodiments, UE 104 may be referred to as a unit, station, terminal, or client, and other instances thereof. Alternatively or additionally, UE 104 may be referred to as an Internet of Things (IoT) device, Internet of Everything (IoE) device, or Machine-Type Communication (MTC) device, and other instances thereof.

[0046] UE 104 can support direct wireless communication with other UE 104 via a communication link. For example, UE 104 can support direct wireless communication 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 may be referred to as a sidelink. For example, UE 104 can support direct wireless communication with another UE 104 via a PC5 interface.

[0047] NE 102 may support communication with CN 106 or another NE 102, or both. For example, NE 102 may interface with other NE 102 or CN 106 via one or more backhaul links (e.g., S1, N2, N2, or network interfaces). In some implementations, NE 102 may communicate directly with each other. In some other implementations, NE 102 may communicate indirectly with each other (e.g., via CN 106). In some implementations, one or more NE 102 may include sub-components, such as access network entities, which may be instances of Access Node Controllers (ANCs). The ANC may communicate with one or more UE 104s via one or more other access network transmitting entities, which may be referred to as radio headends, smart radio headends, or transmit-receive points (TRPs).

[0048] CN 106 can support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. CN 106 can be an evolved packet core (EPC) or a 5G core (5GC), which may include control plane entities (e.g., Mobility Management Entity (MME), Access and Mobility Management Function (AMF)) that manage access and mobility, and user plane entities (e.g., Serving Gateway (S-GW), Packet Data Network (PDN) Gateway (P-GW), or User Plane Function (UPF)) that route packets or interconnects to external networks. 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, signaling bearers, etc.) of one or more UEs 104 served by one or more NEs 102 associated with CN 106.

[0049] CN 106 can communicate with a packet data network (e.g., via S1, N2, N2, or another network interface) through one or more backhaul links. The packet data network may contain an application server. In some implementations, one or more UEs 104 can communicate with the application server. UE 104 can establish a session (e.g., a Protocol Data Unit (PDU) session or the like) with CN 106 via NE 102. CN 106 can use the established session (e.g., an established PDU session) to route traffic (e.g., control information, data, and the like) between UE 104 and the application server. A PDU session can be an instance of a logical connection between UE 104 and CN 106 (e.g., one or more network functions of CN 106).

[0050] In the wireless communication system 100, NE 102 and UE 104 can use the resources of the wireless communication system 100 (e.g., time resources (e.g., symbols, time slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers)) to perform various operations (e.g., wireless communication). In some embodiments, NE 102 and UE 104 may support different resource structures. For example, NE 102 and UE 104 may support different frame structures. In some embodiments, such as in 4G, NE 102 and UE 104 may support a single frame structure. In some other embodiments, such as in 5G and other suitable radio access technologies, NE 102 and UE 104 may support various frame structures (e.g., multiple frame structures). NE 102 and UE 104 may support various frame structures based on one or more sets of parameters.

[0051] The wireless communication system 100 may support one or more parameter sets, and the parameter sets may include subcarrier spacing and cyclic prefixes. A first parameter set (e.g., μ = 0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some embodiments, the first parameter set (e.g., μ = 0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one time slot per frame. A second parameter set (e.g., μ = 1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third parameter set (e.g., μ = 2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth parameter set (e.g., μ = 3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth parameter set (e.g., μ = 4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

[0052] Time intervals for resources (such as communication resources) can be organized according to frames (also known as radio frames). Each frame may have a duration, for example, 10 milliseconds (ms). In some embodiments, each frame may contain multiple subframes. For example, each frame may contain 10 subframes, and each subframe may have a duration, for example, 1 ms. In some embodiments, each frame may have the same duration. In some embodiments, each subframe of a frame may have the same duration.

[0053] Alternatively, the time intervals of resources (e.g., communication resources) can be organized according to time slots. For example, a subframe may contain a certain number (e.g., a set of parameters). The number of time slots in each subframe may also depend on one or more parameter sets supported in the wireless communication system 100. For example, the first, second, third, fourth, and fifth parameter sets (e.g., μ=0, μ=1, μ=2, μ=3, μ=4) associated with corresponding subcarrier intervals of 15kHz, 30kHz, 60kHz, 120kHz, and 240kHz can respectively 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. Each time slot may contain a certain number (e.g., a set of parameters) of symbols (e.g., Orthogonal Frequency Division Multiplexing (OFDM) symbols). In some embodiments, the number (e.g., quantity) of time slots in a subframe may depend on the parameter set. For a normal cyclic prefix, a time slot may contain 14 symbols. For an extended cyclic prefix (e.g., applicable to a 60 kHz subcarrier spacing), a time slot may contain 12 symbols. The relationship between the number of symbols per time slot, the number of time slots per subframe, and the number of time slots per frame for the normal and extended cyclic prefixes may depend on the parameter set. It should be understood that references to the first parameter set (e.g., μ = 0) associated with the first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and time slots.

[0054] In the wireless communication system 100, the electromagnetic (EM) spectrum can be divided into various categories, bands, channels, etc., based on frequency or wavelength. For example, the wireless communication system 100 may support one or more operating frequency bands, such as frequency ranges represented as FR1 (410MHz to 7.125GHz), FR2 (24.25GHz to 52.6GHz), FR3 (7.125GHz to 24.25GHz), FR4 (52.6GHz to 114.25GHz), FR4a or FR4-1 (52.6GHz to 71GHz), and FR5 (114.25GHz to 300GHz). In some embodiments, NE 102 and UE 104 may perform wireless communication on one or more of the operating frequency bands. In some embodiments, FR1 may be used by NE 102 and UE 104, as well as other equipment or devices, for cellular communication services (e.g., control information, data). In some implementations, FR2 can be used by NE 102 and UE 104, as well as other equipment or devices, for short-range, high data rate capabilities.

[0055] FR1 can be associated with one or more parameter sets (e.g., at least three parameter sets). For example, FR1 can be associated with: a first parameter set (e.g., μ = 0) containing a 15 kHz subcarrier spacing; a second parameter set (e.g., μ = 1) containing a 30 kHz subcarrier spacing; and a third parameter set (e.g., μ = 2) containing a 60 kHz subcarrier spacing. FR2 can be associated with one or more parameter sets (e.g., at least two parameter sets). For example, FR2 can be associated with: a third parameter set (e.g., μ = 2) containing a 60 kHz subcarrier spacing; and a fourth parameter set (e.g., μ = 3) containing a 120 kHz subcarrier spacing.

[0056] In NR, accommodating multiple uncoordinated UEs in unlicensed spectrum requires defining a channel access procedure for NR. Following a successful channel access procedure performed by a communication node, the channel can be used by the communication node for a period of time until the end of that period. This period may be referred to as COT. During the COT, one or more transmissions can be exchanged between communication nodes, where the transmissions can be downlink (DL) transmissions or uplink (UL) transmissions.

[0057] Dynamic channel access procedures are typically used by a BS or UE to access channels in unlicensed spectrum. Dynamic channel access procedures can be based on Listen-Before-Speak (LBT), where the transmitter listens for potential transmission activity on the channel before transmitting and, in some cases, applies a random backoff time. Two main types of dynamic channel access procedures are defined in the NR. One is Type 1 dynamic channel access procedure, also known as LBT Type 1 or LBT cat4. The other is Type 2 dynamic channel access procedure, also known as LBT Type 2.

[0058] The Type 1 Dynamic Channel Access Procedure can be used to initiate data transmission at the start of a COT (Content Controller). The initiator for the Type 1 Dynamic Channel Access Procedure can be either a BS (Browser) or a UE (User Equipment). The Type 1 Dynamic Channel Access Procedure can be summarized as follows.

[0059] First, the initiator listens and waits for at least one period of time, referred to as the delay duration, until the channel (e.g., the channel) becomes available. The delay duration can be 16 μs or a certain number (e.g., “m” in Table 1 or Table 2 below). p The 9μs time slots (which will be explained below) are composed of [the data]. As shown in Tables 1 and 2, "m" p The value of 'p' depends on the value of CAPC. Therefore, the delay duration depends on the value of CAPC, as shown in Table 1 or Table 2 below. If the received energy is below the threshold for at least 4 μs in each 9 μs time slot, then the channel is declared available.

[0060] Once the channel is declared available during the delay period, the transmitter initiates a random backoff procedure, during which it will wait for a random period of time.

[0061] The UE initiates the random backoff procedure by initializing the backoff timer with a random number within the contention window (CW). The random number is drawn from a uniform distribution [0, CW] and represents the timer duration (e.g., represented by the random number multiplied by 9 μs) before transmission can proceed. The value of “CW” can be selected from “Allowed CWs” in Table 1 or Table 2 below. p Size (minimum value is represented as CW) min，p And the maximum value is represented as CW max，p This depends on the value of CAPC.

[0062] The backoff timer is decremented by 1 for each sensing time slot duration (e.g., 9 μs) when the channel is sensed to be idle; whenever the channel is sensed to be busy, the backoff timer is paused until the channel has been idle for the delay duration.

[0063] Once the backoff timer expires (e.g., the backoff timer decrements to 0), the random backoff procedure is complete, and the transmitter has acquired the channel and can use it to transmit until the maximum channel occupancy time (MCOT) (e.g., T in Table 1 below). mcot,p Or T in Table 2 below ulmcot,p This depends on the value of CAPC.

[0064] Tables 1 and 2 below illustrate the exemplary CAPC of DL and the CAPC and m of UL, respectively. p CW min,p CW max,p T mcot,p T ulmcot,p and permitted CW p The corresponding values ​​for the size. Table 1 is the same as Table 4.1.1-1 in TS 37.213, and Table 2 is the same as Table 4.2.1-1 in TS 37.213. When the BS wishes to initiate channel occupancy for DL ​​transmission, it can determine the CAPC value before executing the Type 1 channel access procedure, and then determine the corresponding value (e.g., m) for the Type 1 channel access procedure according to Table 1. p CW min,p CW max,p T mcot,p and permitted CW p (Size). When a UE wishes to initiate channel occupancy for UL transmission, it can determine the CAPC value before executing the Type 1 channel access procedure, and then determine the corresponding value (e.g., m) for the Type 1 channel access procedure according to Table 2. p CW min,p CW max,p Tulmcot,p and permitted CW p size).

[0065] Table 1: Channel Access Priority Categories for DL

[0066]

[0067] Table 2: Channel Access Priority Categories for UL

[0068]

[0069] The size of the contention window can be adjusted based on HARQ reports received from the transmitter during a reference interval that covers the start of the COT. For each received HARQ report, if a negative HARQ report (e.g., a negative acknowledgment (NACK)) is received, the contention window is approximately doubled to the limit CW. max,p For positive HARQ reports (e.g., ACKs), the contention window is reset to its minimum value, i.e., CW = CW. min,p .

[0070] Type 2 Dynamic Channel Access Procedure can be used for COT sharing and detecting burst transmissions. Depending on the duration of the gap in the COT (also known as the "COT sharing gap"), Type 2 Dynamic Channel Access Procedure can be further classified into three procedures, the specific procedure to be used depending on the duration of the gap between two transmission bursts.

[0071] • Type 2A Dynamic Channel Access Procedure (also known as LBT cat2 or LBT type 2A): It is used when a burst of transmissions is detected with a gap of 25 μs or more.

[0072] • Type 2B Dynamic Channel Access Procedure (also known as LBT Type 2B): It is used when the gap is 16μs.

[0073] • Type 2C Dynamic Channel Access Procedure (also known as LBT Type 2C): It is used when the interval after the previous transmit burst is 16 μs or less.

[0074] For the 2C type dynamic channel access procedure, no idle sensing is required between transmit bursts. In this scenario, the duration of a transmit burst is limited to a maximum of 584 μs. This short transmit burst can carry a small amount of user data and uplink control information (UCI), such as HARQ status reports and channel state information (CSI) reports.

[0075] The Type 2A and Type 2B dynamic channel access procedures are similar to the Type 1 dynamic channel access procedure, but without random backoff. That is, in the Type 2A and Type 2B dynamic channel access procedures, if the channel is detected to be idle during the gap, it is declared available; if it is detected to be busy, COT sharing fails and transmission cannot be performed using this COT sharing. If the COT sharing gap is 16 μs, the Type 2B dynamic channel access procedure can be used, and the channel must be detected to be idle during the 16 μs gap before the next transmission burst. If the COT sharing gap is 25 μs or longer, the Type 2A dynamic channel access procedure can be used, and the channel must be detected to be idle for at least 25 μs immediately before the next transmission burst.

[0076] The above embodiments provide several dynamic channel access procedures in the unlicensed spectrum of NR. These dynamic channel access procedures can also be adapted for sidelink transmissions in the unlicensed spectrum.

[0077] Sidelink synchronization information is carried in the S-SSB, which consists of the Physical Sidelink Broadcast Channel (PSBCH), the Sidelink Primary Synchronization Signal (S-PSS), and the Sidelink Auxiliary Synchronization Signal (S-SSS). Figure 2A This section describes exemplary S-SSB time slots according to some embodiments of the present disclosure. Figure 2A In the example, the normal cyclic prefix (CP) is used.

[0078] refer to Figure 2A The S-SSB occupies one time slot in the time domain and 11 resource blocks (RBs) in the frequency domain. Each RB spans 12 subcarriers, therefore the S-SSB bandwidth is 132 (11 × 12) subcarriers. Figure 2A In an example, the S-SSB time slot can contain a total of 14 OFDM symbols, such as symbols #0 to #13. The S-PSS is repeatedly transmitted on the second and third symbols (e.g., symbols #1 and #2) within the S-SSB time slot. The S-SSS is repeatedly transmitted on the fourth and fifth symbols (e.g., symbols #3 and #4) within the S-SSB time slot. The S-PSS and S-SSS occupy 127 subcarriers in the frequency domain, from the third subcarrier relative to the S-SSB bandwidth to the 129th subcarrier.

[0079] S-PSS and S-SSS are collectively referred to as the Side Link Synchronization Signal (SLSS). SLSS is used for time and frequency synchronization. By detecting the SLSS sent by the synchronization reference UE (also known as the SyncRef UE), the UE can synchronize with the SyncRef UE and estimate the start of the frame and the carrier frequency offset.

[0080] S-PSS can be generated from the longest sequence (m-sequence) using the same design (i.e., generator polynomial, initial values, and cyclic shifts, etc.) used in the 3GPP archives to generate the primary synchronization signal (PSS). In NR Uu, there are three candidate sequences for PSS. However, only two candidate sequences are used for S-PSS.

[0081] S-SSS can be generated from a Gold sequence using the same design (i.e., generator polynomial, initial values, and cyclic shifts, etc.) used in the 3GPP archives for generating Gold sequences for auxiliary synchronization signals (SSS). This results in 336 candidate sequences for S-SSS, just like the SSS used in NR Uu.

[0082] For SLSS transmission within an S-SSB, the SyncRef UE can select the S-PSS and S-SSS from candidate sequences based on the SLSS identifier (ID). The SLSSID represents the identifier of the SyncRef UE and conveys the priority of the SyncRef UE, just as in LTE vehicle-to-everything (V2X) communication. Each SLSSID corresponds to a unique combination of S-PSS and S-SSS from 2 S-PSS candidate sequences and 336 S-SSS candidate sequences.

[0083] The primary purpose of the PSBCH is to provide system-wide information and synchronization information, which the UE needs to establish a sidelink connection. Figure 2A In this example, the PSBCH is transmitted on the first symbol (e.g., symbol #0) and eight symbols (e.g., symbols #5 to #12) after S-SSS in the S-SSB time slot. When using extended CP, the PSBCH is transmitted on the first symbol and six symbols after S-SSS in the S-SSB time slot. The PSBCH occupies 132 subcarriers in the frequency domain. The PSBCH in the first symbol of the S-SSB time slot is used for automatic gain control (AGC). The last symbol in the S-SSB time slot (e.g., symbol #13) is used as a guard symbol.

[0084] Figure 2A The structure of the S-SSB time slot in this paper is for illustrative purposes only. It is understood that as network architecture and new service scenarios evolve, the S-SSB may have other structures (e.g., the S-SSB may contain 4 or 6 OFDM symbols in the time domain), which should not affect the principles of this application.

[0085] Figure 2B This describes an exemplary distribution of S-SSB timings in the time domain according to some embodiments of the present disclosure.

[0086] Figure 2BThe S-SSB period is used as an example for illustration. The figure also illustrates the resource pool. The resource pool defines the total time-domain and frequency-domain resources available for SL transmission within a carrier. In the embodiments of this application, SL transmission can refer to at least one of Physical Side Link Control Channel (PSCCH) transmission or Physical Uplink Shared Channel (PSSCH) transmission. In the time domain, the resource pool consists of a set of time slots that repeat within the resource pool period. Although the set of time slots within the resource pool is logically organized in a continuous manner, in practice, the time slots within the resource pool can be discretely distributed in the time domain.

[0087] like Figure 2B The data shows that the S-SSB period contains N S-SSB opportunities, which are marked by S-SSB opportunity #0, S-SSB opportunity #1, S-SSB opportunity #2, ..., S-SSB opportunity #N-1 respectively.

[0088] The length of the S-SSB period is Figure 2B This is marked as the "S-SSB period". There is a time offset between the start of the S-SSB period and the first S-SSB opportunity within the S-SSB period. Figure 2B The middle is marked as "T" Offset "There exists a time interval between two adjacent S-SSB opportunities (e.g., between the end of one S-SSB opportunity and the beginning of the next S-SSB opportunity), which is in..." Figure 2B The middle is marked as "T" Interval ".

[0089] In 3GPP Release 16 (Rel-16) or Release 17 (Rel-17), the S-SSB period can consist of 160ms, as specified in NRV2X. However, with the development of network architecture and new service scenarios, the S-SSB period may have other values, which should not affect the principles of this disclosure. Figure 2B In examples, the distribution of S-SSB timing can be represented by at least one of the following parameters: S-SSB time period, T Offset T Interval Or N, as described above.

[0090] Figure 2C This describes an exemplary distribution of S-SSB timings in the time domain, organized in a grouped manner, according to some embodiments of this disclosure.

[0091] Figure 2C Let's take the S-SSB period as an example. The length of the S-SSB period is... Figure 2CThe time period is marked as "S-SSB period". The S-SSB period contains N1 S-SSB groups, namely S-SSB group #0, S-SSB group #1, ..., and S-SSB group #N1-1. Each S-SSB group contains N2 consecutive S-SSB opportunities, namely S-SSB opportunity #0, S-SSB opportunity #1, ..., and S-SSB opportunity #N2-1.

[0092] There is a time offset between the start of the S-SSB period and the start of the first S-SSB group within the S-SSB period. Figure 2C The middle is marked as "T" OffsetGroup "There exists a time interval between two adjacent S-SSB groups (e.g., between the end of the previous S-SSB group and the beginning of the next S-SSB group), which is in..." Figure 2C The middle is marked as "T" IntervalGroup Therefore, in Figure 2C In an example, the S-SSB timing distribution can be defined by at least one of the following parameters: parameter "S-SSB time period", parameter "T OffsetGroup ", parameter "T" IntervalGroup ", parameter "N1" or parameter "N2".

[0093] According to some embodiments of this application, for unlicensed spectrum, a frequency range (e.g., BWP, carrier, resource pool, etc.) can be divided into multiple channels on which channel access procedures are defined. Each channel may be referred to as an RB set. Operation on a carrier may require a guard band between RB sets. In some embodiments, the size of the guard band can be selected such that filtering is not required to ensure that transmission on one RB set does not cause significant interference to adjacent RB sets that are not available for transmission.

[0094] For example, the concept of an "RB set" is specified in 5G NR version 16 for unlicensed spectrum (NR-U), defining precisely available RBs that are not included in inter-cell or intra-cell guard bands. Guard bands and RB sets are configured by RRC signaling on a unit of Common Resource Blocks (CRBs). Specifically, when a UE is configured with intraCellGuardBand for a carrier, the UE is provided with N on the carrier. RB-set -1 protection zones within a single cell, each consisting of a start CRB and an end CRB (i.e., and Definition. Protective zone separation N within the community. RB-set Each of the RB sets consists of a start CRB and an end CRB (i.e., ...). and Definition. UE determination. And the remaining end and start CRB are and When the UE is not configured with intraCellGuardBand, the UE depends on the μ and carrier size. The default intra-cell protection band mode from TS38.101 is used to determine the intra-cell protection band and the corresponding RB set. The specific definitions of the variables or parameters mentioned above can be found in the 3GPP standard archives.

[0095] As an example, a carrier wider than 20MHz can be divided into multiple 20MHz channels on which channel access procedures are defined. Each 20MHz channel can be referred to as an RB set.

[0096] Table 3 below shows the number of RBs (e.g., N) in different bandwidths of different SCSs included in FR1 (e.g., 450MHz to 7125MHz). RB ).

[0097] Table 3: Maximum Transmit Bandwidth Configuration N for FR1 RB

[0098]

[0099] Referring to Table 3, taking a 20MHz bandwidth as an example, for a 15kHz SCS, the 20MHz bandwidth contains 106 RBs (for example, the RB set can contain 106 RBs); for a 30kHz SCS, the 20MHz bandwidth contains 51 RBs.

[0100] In the NR unlicensed spectrum (NR-U), a BS can access multiple channels to perform downlink transmissions according to either the Type A multichannel access procedure or the Type B multichannel access procedure.

[0101] In Type A multi-channel access procedures, the BS can access each channel c i The channel access procedure (e.g., type 1 channel access procedure) is executed on ∈C, where C is a set of channels on which the BS expects to transmit, and u = 0, 1, ..., q-1 and q are the number of channels on which the BS expects to transmit.

[0102] In Type A multichannel access procedures, if the BS is configured with a carrier without an in-cell guard band, then if the BS fails to access any channel within the carrier bandwidth, the BS cannot access channel c within the carrier bandwidth. i Emit on ∈C.

[0103] In the Type B multichannel access procedure, the BS can perform the following operations:

[0104] 1) BS can select channel c j ∈C, where C (e.g., {c0, c1, ..., c) q-1Let q be a set of channels on which the BS expects to transmit, and let q be the number of channels on which the BS expects to transmit. Channel c j The following can be selected by BS:

[0105] ·BS can be accessed via multiple channels c i Before each emission on ∈C, c is uniformly randomly selected from C. j Choose C j ,or

[0106] ·BS can be selected as c j The frequency should not exceed once per second.

[0107] 2) In order to use channel c j The BS can transmit on channel c. j Execute the Type 1 channel access procedure.

[0108] 3) In order to use channel c i ≠c j c i Transmitted on ∈C, for each channel c i BS can be immediately following channel c j At least one sensing interval T before launch mc =25µs sensing channel c i And BS can immediately follow the sensing of channel c i At least the sensing interval T mc After the inner channel is idle, it will be in channel c. i Transmission is performed on channel c. i Considered in T mc The prerequisite for the channel to be idle is that the channel c i In which, at a given interval T mc In the middle of channel c j The entire duration of this idle sensing is sensed as idle.

[0109] In the Type B multichannel access procedure, exceeding the T values ​​given in Table 1... m cot,p During the specified time period, the BS cannot be on channel c i ≠c j c i Emitted on ∈C, where T m cot,p The value used for channel c j The channel access parameters are used to determine this.

[0110] In Type B multichannel access procedures, if the BS is configured with a carrier without an in-cell guard band, then if the BS fails to access any channel within the carrier bandwidth, the BS cannot access channel c within the carrier bandwidth. i Emit on ∈C.

[0111] Type A and Type B multichannel access procedures in NR-U can be used as baselines for designing multichannel access procedures in SL unlicensed spectrum (SL-U). However, since both Type A and Type B multichannel access procedures are designed for NR-U where the channels used for transmission are determined and allocated by the BS, these procedures are not suitable for direct application in SL-U. For example, in SL-U, the UE can determine which channel(s) to transmit on. The UE can determine the channel access type (e.g., Type 1 or Type 2) to use on the channel by considering COT information. Furthermore, selecting channels for S-SSB transmission, SL transmission (e.g., at least one of PSCCH or PSSCH transmission), or PSFCH transmission may require consideration of their individual characteristics. Therefore, it is necessary to investigate how to design multichannel access procedures for SL-U.

[0112] This disclosure provides a solution for multi-channel access in SL-U. Specifically, for dynamic channel access modes with multi-channel configurations in SL-U, embodiments of this disclosure provide multi-channel access procedures for S-SSB transmission, SL transmission, and PSFCH transmission. The multi-channel access procedures in SL-U in the embodiments of this disclosure can be based on Type A and Type B multi-channel access procedures in NR-U, further considering resource utilization conditions, SL-U characteristics, and transmission characteristics (e.g., S-SSB transmission, SL transmission, or PSFCH transmission). Further details will be described below in conjunction with the accompanying drawings.

[0113] Figure 3 A flowchart illustrating an exemplary method according to aspects of this disclosure. Figure 3 The operation of the method described herein can be performed by the UE (e.g., UE) described herein. Figure 1 This can be performed by the UE (104) or other devices with similar functionality. In some implementations, the UE can execute a set of instructions to control the functional elements of the UE to perform the described operations or functions.

[0114] like Figure 3 As shown, in step 302, the UE can select a set of channels for transmissions via SL. The transmissions can be one of the following: S-SSB transmission, SL transmission (e.g., PSCCH transmission and / or PSSCH transmission), or PSFCH transmission. As described above, channels can also be referred to as RB sets.

[0115] In step 304, the UE can determine the availability of each channel in the set of channels by performing a type-independent multichannel access procedure or a type-dependent multichannel access procedure on the set of channels used for transmission.

[0116] In some embodiments, in a type-independent multichannel access procedure: a channel access procedure is performed independently for each channel within the set of channels; and the channel access type for each channel within the set of channels is determined based on whether the channel is within a COT or whether the channel is within a COT shared by the UE for performing transmission. The channel access type may refer to, for example, a Type 1 dynamic channel access procedure or a Type 2 dynamic channel access procedure as described above.

[0117] In some embodiments, in a type-dependent multichannel access procedure: if at least one channel in the set of channels is outside the COT, a Type 1 dynamic channel access procedure is performed on the first channel in the at least one channel, and a Type 2 dynamic channel access procedure is performed on each of the remaining channels in the set of channels other than the first channel; if all channels in the set of channels are within the COT, a Type 2 dynamic channel access procedure is performed independently on each channel in the set of channels.

[0118] Whether to execute a type-independent or type-dependent multichannel access procedure depends on the UE's implementation scheme.

[0119] The following embodiments provide specific operations in steps 302 and 304 when performing type-independent or type-dependent multichannel access procedures for different transmission execution types.

[0120] Example 1

[0121] In Embodiment 1, the UE may execute a type-independent multichannel access procedure in step 304. Embodiment 1 can be divided into Embodiment 1-1, Embodiment 1-2, and Embodiment 1-3 for different transmissions.

[0122] Example 1-1

[0123] In Embodiment 1-1, the UE may expect to transmit an S-SSB and determine to execute a Type Independent Multichannel Access procedure. That is, in Embodiment 1-1, the UE selects the transmission of the set of channels for S-SSB transmission in step 302, and the UE expects to select at least one channel from the set of channels for S-SSB transmission.

[0124] In some embodiments, the UE may randomly select channels within a frequency range (e.g., BWP, carrier, resource pool, etc.) to form the set of channels.

[0125] In some embodiments, when the UE selects the set of channels, the UE may preferentially select an anchor channel to be included in the set of channels. For example, an anchor channel may refer to the channel located by the S-SSB as indicated by sl-AbsoluteFrequencySSB-r16 as specified in the 3GPP standard document. For another example, an anchor channel may be defined as the channel on which the default S-SSB timing is located. Therefore, a non-anchor channel may refer to a channel other than the indicated anchor channel.

[0126] In step 304, the UE can determine the availability of each channel within the set of channels by performing a type-independent multichannel access procedure on the set of channels used for S-SSB transmission. In some embodiments, performing a type-independent multichannel access procedure on the set of channels used for S-SSB transmission may include at least the following operations.

[0127] First, the UE can individually determine the channel access type (e.g., type 1 or type 2) of the channel access procedure on each channel within the group of channels, based on whether the target S-SSB timing is within the COT. The location of the target S-SSB timing in the time domain can be determined by the distribution of S-SSB timings in the time domain, for example... Figure 2B or Figure 2C The distribution is shown in the diagram. The location of the target S-SSB opportunity in the frequency domain can be indicated by the channel index or channel identifier (ID). As an example, if the target S-SSB opportunity on the channel is within the COT, then the UE can determine that the channel access type on the channel is type 2. Otherwise, the UE can determine that the channel access type on the channel is type 1.

[0128] Figure 4 This describes exemplary S-SSB timing and COT location for SL transmission in a channel, according to aspects of this disclosure. Figure 4 In this example, the S-SSB timing is within the COT used for SL transmission.

[0129] refer to Figure 4 In a channel (e.g., channel #j), the COT for SL transmission may begin with time slot #i and have a length of four time slots (e.g., containing time slots #i, #i+1, #i+2, and #i+3). The COT may be initiated by an LBT type 1 procedure before time slot #i. Each time slot may contain 14 OFDM symbols (e.g., from symbol 0 to symbol 13). Within the COT, time slot #i+2 is the S-SSB timing. Each of the other time slots in the COT may be used for SL transmission, which may contain at least one of PSCCH or PSSCH transmission.

[0130] When a UE knows information related to the COT (Confirmation of the Occupation), for example, if the UE is a COT-initiating UE, a COT-responding UE with which the COT-initiating UE can share the COT, or a UE that detects COT-related information (e.g., the remaining COT duration), the UE can determine whether the target S-SSB timing on the channel is within the COT, for example, based on the COT-related information and the S-SSB timing distribution. If the UE does not know the COT-related information, then the UE can assume that the target S-SSB timing on the channel is outside the COT. The motivation for providing a UE (such as a COT-initiating UE and a COT-responding UE) with a higher channel access chance to detect COT-related information is that its S-SSB transmission has a smaller impact on the interruption of the COT.

[0131] After individually determining the channel access type (e.g., type 1 or type 2) for each channel within the set of channels, the UE can perform a channel access procedure for each channel based on the channel access type individually determined for each channel within the set of channels.

[0132] For example, if the UE determines that the channel access type on the channel is Type 2, the UE can perform a Type 2 dynamic channel access procedure toward the target S-SSB timing to determine the availability of the channel (i.e., whether the channel is available). If the UE determines that the channel access type on the channel is Type 1, the UE can perform a Type 1 dynamic channel access procedure toward the target S-SSB timing to determine whether the channel is available.

[0133] Subsequently, in step 304, the UE can determine the availability of each channel within the set of channels. In other words, the UE can determine which channel(s) within the set of channels are available.

[0134] After determining the available channels within the set of channels, the UE can select a channel from the available channels to perform S-SSB transmission. In some embodiments, the UE can preferentially perform S-SSB transmission on the anchor channel.

[0135] In some instances, if an anchor channel within the set of channels is determined to be available, the UE may select an anchor channel to perform S-SSB transmission. The UE may further determine whether to transmit S-SSB on an available non-anchor channel according to the rules specified in the SL-U.

[0136] In some other instances, if it is determined in step 304 that no anchor channel is available, the UE may perform one of the following actions. The motivation is to reduce COT loss.

[0137] • Randomly select a channel from all available channels within the aforementioned group to perform S-SSB transmission;

[0138] • Randomly select a channel from at least one available channel within the set of channels and within the COT to perform S-SSB transmission;

[0139] • Select all available channels within the aforementioned group of channels to perform S-SSB transmission;

[0140] • Select all available channels within the set of channels and within the COT to perform S-SSB transmission; or

[0141] • Select a channel from at least one channel within the set of channels and within the COT to perform S-SSB transmission based on the CAPC corresponding to the COT: For example, if the CAPC corresponding to the COT is higher than or equal to the CAPC threshold, then the UE may select a channel within the COT to perform S-SSB transmission.

[0142] In some embodiments, the UE may obtain the CAPC threshold based on configuration (i.e., configure the CAPC threshold for the UE). Configuring the CAPC threshold for the UE means that the CAPC threshold may be obtained by, for example, the BS (e.g., Figure 1 The NE 102 shown in the diagram is transmitted to the UE via at least one of the following: SIB message, MIB message, RRC signaling, MAC CE or DCI, so that the UE can receive the CAPC threshold from the BS.

[0143] In some embodiments, the UE may obtain the CAPC threshold based on a pre-configured, defined, or predefined configuration (i.e., pre-configured, defined, or predefined CAPC threshold for the UE). Pre-configured, defined, or predefined CAPC threshold for the UE means that the CAPC threshold can be hardwired into the UE or stored on the UE's Subscriber Identity Module (SIM) or Universal Subscriber Identity Module (USIM) card, so that the UE can obtain the CAPC threshold within the UE.

[0144] Examples 1-2

[0145] In Embodiments 1-2, the UE may expect to transmit PSCCH and / or PSSCH and determine to execute a Type Independent Multiple Access Procedure. That is, in Embodiments 1-2, the UE selects the transmission of the set of channels for SL transmission in step 302, and the UE expects to select at least one channel from the set of channels for SL transmission.

[0146] In some embodiments, when the UE selects the set of channels for SL transmission, the following principles may be considered:

[0147] • Principle #1: When performing an SL transmission, the responding UE may at least use the COT shared by the COT-initiated UE when the responding UE is in the channel corresponding to the shared COT.

[0148] By considering principle #1, when a UE selects the aforementioned set of channels for SL transmission, the UE can preferentially select a channel within the COT shared with the UE, at least when the SL transmission is intended for a UE to initiate COT. In some instances, the UE can preferentially select a channel within the COT shared with the UE, at least when the SL transmission is intended for a UE to initiate COT and the remaining COT duration meets the UE's transmission requirements. The motivation for this selection method is to increase the success probability of channel access procedures on the channel and increase time-domain resources on the channel.

[0149] In step 304, the UE can determine the availability of each channel within the set of channels by performing a type-independent multichannel access procedure on the set of channels used for SL transmission. In some embodiments, performing a type-independent multichannel access procedure on the set of channels used for SL transmission may include at least the following operations.

[0150] First, the UE can individually determine the channel access type (e.g., type 1 or type 2) on each of the channels in the set of channels based on whether each channel is within a COT shared by the UE for performing at least one SL transmission and whether the SL transmission is at least intended for a UE to initiate the COT. This channel access type determination method also considers principle #1.

[0151] As an example, if the channel is within a COT shared with a UE (e.g., the UE is a COT-responsive UE) for performing at least one SL transmission, and the SL transmission is intended at least for a UE to initiate a COT, then the UE can determine that the channel access type on the channel is type 2. Otherwise, the UE can determine that the channel access type on the channel is type 1.

[0152] After individually determining the channel access type (e.g., type 1 or type 2) for each channel within the set of channels, the UE can perform a channel access procedure for each channel based on the channel access type individually determined for each channel within the set of channels.

[0153] For example, if the UE determines that the channel access type on the channel is Type 2, the UE can perform a Type 2 dynamic channel access procedure to determine the availability of the channel (i.e., whether the channel is available). If the UE determines that the channel access type on the channel is Type 1, the UE can perform a Type 1 dynamic channel access procedure to determine whether the channel is available.

[0154] Subsequently, in step 304, the UE can determine the availability of each channel within the set of channels. In other words, the UE can determine which channel(s) within the set of channels are available. Then, the UE can select all the channels within the set of channels determined to be available in step 304 to perform SL transmission.

[0155] In some embodiments, when a channel is determined to be available within the COT (e.g., the channel is determined to be available based on a Type 2 dynamic channel access procedure), the UE may determine whether to perform an SL transmission on the channel based on the remaining COT duration. For example, if the remaining COT duration is longer than or equal to a COT duration threshold, then the UE may determine to perform an SL transmission on the channel. The UE may obtain the COT duration threshold based on configuration, pre-configuration, definition, or predefined criteria. All the above definitions regarding configuration, pre-configuration, definition, and predefined criteria also apply herein.

[0156] In some embodiments, the start symbol for SL transmission may be the first symbol in the time slot (e.g., symbol #0). In some other embodiments, for a time slot with two candidate start symbols for SL transmission, the position of the first start symbol may be (pre)configured from symbols {#0, #1, #2, #3, #4, #5, #6} per BWP, and the default position of the first start symbol is symbol #0 if no (pre)configuration is performed; and the position of the second start symbol may be (pre)configured from symbols {#3, #4, #5, #6, #7} per BWP. The (pre)configuration of the second start symbol needs to meet the following requirements: within the time slot, the second start symbol is later than the first start symbol, and the number of symbols for SL transmission starting from the second start symbol is not less than 6. In such embodiments, the start symbol for SL transmission may be either the first start symbol or the second start symbol.

[0157] Examples 1-3

[0158] In embodiments 1-3, the UE may expect to transmit a PSFCH and determine to execute a type-independent multichannel access procedure. That is, in embodiments 1-3, the UE selects the transmission of the set of channels for PSFCH transmission in step 302, and the UE expects to select at least one channel from the set of channels for PSFCH transmission.

[0159] In some embodiments, the UE may select its PSFCH resources to correspond to the channels transmitted by the SL for HARQ feedback transmitted by the UE to form the set of channels.

[0160] In step 304, the UE can determine the availability of each channel within the set of channels by performing a type-independent multichannel access procedure on the set of channels used for PSFCH transmission. In some embodiments, performing a type-independent multichannel access procedure on the set of channels used for PSFCH transmission may include at least the following operations.

[0161] First, the UE can individually determine the channel access type (e.g., type 1 or type 2) on each of the channels in the set of channels based on whether each channel is within a COT shared with the UE for performing PSFCH transmissions and whether at least one of the PSFCH transmissions is intended for a UE to initiate a COT. This channel access type determination method can be based on the following principles:

[0162] • Principle #2: When performing a PSFCH transmission, the responding UE may, at least in one of the PSFCH transmissions of the responding UE in the symbol / time slot corresponding to the shared COT, intend to use the COT shared by the COT-initiated UE when the COT-initiated UE is used.

[0163] As an example, if the channel is within a COT shared with a UE (e.g., the UE is a COT-responsive UE) for performing PSFCH transmissions, and at least one of the PSFCH transmissions is intended for a UE to initiate a COT, then the UE can determine that the channel access type on the channel is type 2. Otherwise, the UE can determine that the channel access type on the channel is type 1.

[0164] After individually determining the channel access type (e.g., type 1 or type 2) for each channel within the set of channels, the UE can perform a channel access procedure for each channel based on the channel access type individually determined for each channel within the set of channels.

[0165] For example, if the UE determines that the channel access type on the channel is Type 2, the UE can perform a Type 2 dynamic channel access procedure toward the target PSFCH timing to determine the availability of the channel (i.e., whether the channel is available). If the UE determines that the channel access type on the channel is Type 1, the UE can perform a Type 1 dynamic channel access procedure toward the target PSFCH timing to determine whether the channel is available.

[0166] Subsequently, in step 304, the UE may determine the availability of each channel within the set of channels. In other words, the UE may determine which channel(s) within the set of channels are available. Then, in some embodiments, the UE may select all channels within the set of channels determined to be available in step 304 to perform PSFCH transmission.

[0167] In some embodiments, if the UE is unable to transmit PSFCH on all channels determined to be available (e.g., due to power limitations), the UE may discard PSFCH transmissions based on the priority of the corresponding SL transmission. For example, the UE may discard PSFCH transmissions with lower priority than its corresponding SL transmissions.

[0168] Example 2

[0169] In Embodiment 2, the UE may execute a type-dependent multichannel access procedure in step 304. Embodiment 2 can be divided into Embodiment 2-1, Embodiment 2-2, and Embodiment 2-3 for different transmissions.

[0170] Example 2-1

[0171] In Embodiment 2-1, the UE may expect to transmit an S-SSB and determine to execute a type-dependent multichannel access procedure. That is, in Embodiment 2-1, the UE selects the transmission of the set of channels for S-SSB transmission in step 302, and the UE expects to select at least one channel from the set of channels for S-SSB transmission. For example, the set of channels may be represented as C. Each channel in the set of channels may be represented as c. i ∈C, i=0,1,…q-1, where q is the number of channels included in the set of channels, which is a positive integer.

[0172] In some embodiments, the UE may randomly select channels within a frequency range (e.g., BWP, carrier, resource pool, etc.) to form the set of channels.

[0173] In some embodiments, when the UE selects the set of channels, the UE may preferentially select an anchor channel to be included in the set of channels. As an example, an anchor channel may refer to a channel located by an S-SSB as indicated by sl-AbsoluteFrequencySSB-r16 as specified in the 3GPP standard document. As another example, an anchor channel may be defined as the channel on which the default S-SSB timing is located. In some embodiments, when the UE selects the set of channels, the UE may preferentially select at least one channel outside the COT from the set of channels to be included.

[0174] In step 304, the UE can determine the availability of each channel within the set of channels by performing a type-dependent multichannel access procedure on the set of channels used for S-SSB transmission. In some embodiments, performing a type-dependent multichannel access procedure on the set of channels used for S-SSB transmission may include at least the following operations.

[0175] If at least one channel in the set of channels is outside the COT (Center for Optical Transmission), the UE may select (e.g., randomly select) a first channel within that set of channels. The UE may perform a Type 1 dynamic channel access procedure on the first channel to determine whether an S-SSB opportunity in the first channel is available for S-SSB transmission (i.e., whether the first channel is used). The motivation for this design is to increase the success rate of the channel access procedure while minimizing the impact on the COT. The UE performs a Type 2 dynamic channel access procedure on each of the remaining channels in the set of channels other than the first channel before the start point of the S-SSB opportunity in the first channel.

[0176] As an example, at least one channel outside of COT can be represented as C1, where That is, C1 is a subset of C. The UE can perform the following operations:

[0177] The UE can select the first channel from C1 (e.g., denoted as c). j ), and for channel c j Execute a Type 1 dynamic channel access procedure toward S-SSB timing to determine channel c j Availability (e.g., channel c) j (Whether the S-SSB timing can be used for S-SSB launch).

[0178] For each channel c i ≠c j c i ∈C, the UE can be in channel c j The start point of the S-SSB timing on channel c i Execute the Type 2 dynamic channel access procedure to determine channel c i Availability (i.e., whether the channel is available). For example, the UE can be immediately connected to channel c. j At least one sensing interval T before the start point of the S-SSB timing. mc (e.g. T) mc =25us) sensing channel c i And when channel c is sensed i At least the sensing interval T mc Channel c is determined after the internal state is idle. i It is available.

[0179] When all channels in the set of channels are within the COT, the UE can independently perform a Type 2 dynamic channel access procedure for each channel in the set of channels to determine the availability of each channel (e.g., whether the S-SSB timing in each channel is available for S-SSB transmission).

[0180] Subsequently, in step 304, the UE can determine the availability of each channel within the set of channels. In other words, the UE can determine which channel(s) within the set of channels are available.

[0181] After determining the available channels within the set of channels, the UE can select a channel from the available channels to perform S-SSB transmission. All embodiments described in Example 1-1 for selecting a channel from the available channels to perform S-SSB transmission are also applicable here. Therefore, details are omitted for simplicity.

[0182] Example 2-2

[0183] In Embodiment 2-2, the UE may expect to transmit PSCCH and / or PSSCH and determine to perform a type-dependent multichannel access procedure. That is, in Embodiment 2-2, the UE selects the transmission of the set of channels for SL transmission in step 302, and the UE expects to select at least one channel from the set of channels for SL transmission. For example, the set of channels may be represented as C. Each channel in the set of channels may be represented as c. i ∈C, i=0,1,…q-1, where q is the number of channels included in the set of channels, which is a positive integer.

[0184] In some embodiments, when the UE selects the set of channels, the UE may preferentially select at least one channel outside the COT that is to be included in the set of channels.

[0185] In step 304, the UE can determine the availability of each channel within the set of channels by performing a type-dependent multichannel access procedure on the set of channels used for SL transmission. In some embodiments, performing a type-dependent multichannel access procedure on the set of channels used for SL transmission may include at least the following operations.

[0186] If at least one channel in the set of channels is outside the COT, the UE may select (e.g., randomly select) a first channel within that set of channels. The UE may perform a Type 1 dynamic channel access procedure on the first channel to determine whether the first channel is available for SL transmission. The motivation for this design is to increase the success rate of the channel access procedure while minimizing the impact on the COT. Subsequently, the UE may perform SL transmission on the first channel if the first channel is determined to be available.

[0187] Additionally, the UE may perform a Type 2 dynamic channel access procedure on each of the remaining channels in the set of channels other than the first channel before SL transmission in the first channel (e.g., before the start symbol of SL transmission). In some embodiments, the start symbol of SL transmission may be the first symbol in the time slot (e.g., symbol #0). In some other embodiments, for a time slot with two candidate start symbols for SL transmission, the start symbol of SL transmission may be either the first start symbol or the second start symbol described above. The UE may perform SL transmission on the remaining channels when the remaining channels are determined to be available.

[0188] As an example, at least one channel other than COT can be represented as C2, where That is, c2 is a subset of C. The UE can perform the following operations:

[0189] The UE can select the first channel from C2 (e.g., represented as c). j ), and in channel c jThe Type 1 dynamic channel access procedure is executed to determine channel c. j Availability. The UE can be on channel c j SL launch will be performed when it is determined to be available.

[0190] For each channel c i ≠c j c i ∈C, the UE can be in channel c j Before transmitting on SL, the channel c i Execute the Type 2 dynamic channel access procedure to determine channel c i Availability. For example, the UE can be immediately connected to channel c. j At least one sensing interval T before SL transmission (e.g., before the start symbol of SL transmission). mc (e.g. T) mc =25us) sensing channel c i And when channel c is sensed i At least the sensing interval T mc Channel c is determined after the internal state is idle. i It is available. The UE can use channel c. i When determined to be available in channel c i The UE performs an SL transmission immediately upon sensing channel c. For example, the UE can immediately follow the signal after sensing channel c. i At least the sensing interval T mc After being idle, in channel c i Launch SL from above.

[0191] If all channels within the set of channels are within the COT, the UE can independently perform a Type 2 dynamic channel access procedure for each channel within the set of channels to determine the availability of each channel. Then, the UE can select all channels within the set of channels determined to be available in step 304 to perform SL transmission.

[0192] In some embodiments, when a channel determined to be available is within the COT, the UE may determine whether to perform an SL transmission on the channel based on the remaining COT duration. For example, if the remaining COT duration is longer than or equal to a COT duration threshold, the UE may determine to perform an SL transmission on the channel. The UE may obtain the COT duration threshold based on configuration, pre-configuration, definition, or predefined criteria. All the foregoing definitions regarding configuration, pre-configuration, definition, and predefined criteria also apply herein.

[0193] Example 2-3

[0194] In Embodiments 2-3, the UE may expect to transmit a PSFCH and determine to perform a type-dependent multichannel access procedure. That is, in Embodiments 2-3, the UE selects the transmission of the set of channels as a PSFCH transmission in step 302, and the UE expects to select at least one channel from the set of channels for PSFCH transmission. For example, the set of channels may be represented as C. Each channel in the set of channels may be represented as c. i ∈C, i=0,1,…q-1, where q is the number of channels included in the set of channels, which is a positive integer.

[0195] In some embodiments, the UE may select its PSFCH resources to correspond to the channels transmitted by the SL for HARQ feedback transmitted by the UE to form the set of channels.

[0196] In step 304, the UE can determine the availability of each channel within the set of channels by performing a type-dependent multichannel access procedure on the set of channels used for PSFCH transmission. In some embodiments, performing a type-dependent multichannel access procedure on the set of channels used for PSFCH transmission may include at least the following operations.

[0197] If at least one channel in the set of channels is outside the COT, the UE may select (e.g., randomly select) a first channel within that set of channels. The UE may perform a Type 1 dynamic channel access procedure on the first channel to determine whether a PSFCH timing opportunity in the first channel is available for PSFCH transmission. The motivation for this design is to increase the success rate of the channel access procedure while minimizing the impact on the COT. The UE performs a Type 2 dynamic channel access procedure on each of the remaining channels in the set of channels other than the first channel before the start point of the PSFCH timing opportunity in the first channel.

[0198] As an example, at least one channel outside of COT can be represented as C3, where That is, C3 is a subset of C. The UE can perform the following operations:

[0199] The UE can select the first channel from C3 (e.g., represented as c). j ), and for channel c j Execute a Type 1 dynamic channel access procedure toward the PSFCH timing to determine channel c j Availability (e.g., channel c) j (Whether the PSFCH timing can be used for PSFCH transmission).

[0200] For each channel c i ≠c j c i ∈c, the UE can be in channel c jThe PSFCH timing before the start point of channel c i Execute the Type 2 dynamic channel access procedure to determine channel c i Availability (i.e., whether the channel is available). For example, the UE can be immediately connected to channel c. j At least one sensing interval T before the start point of the PSFCH timing. mc (e.g. T) mc =25us) sensing channel c i And when channel c is sensed i At least the sensing interval T mc Channel c is determined after the internal state is idle. i It is available.

[0201] When all channels in the set of channels are within the COT, the UE can independently perform a Type 2 dynamic channel access procedure for each channel in the set of channels to determine the availability of each channel (e.g., whether the PSFCH timing in each channel is available for PSFCH transmission).

[0202] Subsequently, in step 304, the UE may determine the availability of each channel within the set of channels. In other words, the UE may determine which channel(s) within the set of channels are available. Then, in some embodiments, the UE may select all channels within the set of channels determined to be available in step 304 to perform PSFCH transmission.

[0203] In some embodiments, if the UE is unable to transmit PSFCH on all channels determined to be available (e.g., due to power limitations), the UE may discard PSFCH transmissions based on the priority of the corresponding SL transmission. For example, the UE may discard PSFCH transmissions with lower priority than its corresponding SL transmissions.

[0204] According to some embodiments of this disclosure, for a channel where the SCS is 60kHz, when the S-SSB timing is within the COT, the UE can retain two symbols prior to the S-SSB timing for performing the channel access procedure.

[0205] According to some embodiments of this application, BS (e.g.) Figure 1 The NE 102 shown in the image can be directed to one or more UEs (e.g., Figure 1 The UE 104 transmission configuration information is shown in the image. The configuration information may indicate at least one of the following:

[0206] • The CAPC threshold used to enable the UE to select a channel to perform S-SSB transmission (e.g., as used in Example 1-1); or

[0207] • A COT duration threshold used to enable the UE to determine whether to perform an SL transmission on the channel (e.g., it is used in Example 2-2).

[0208] In an embodiment, the BS may transmit configuration information to one or more UEs via at least one of the following: MIB message, SIB message, RRC signaling, MAC CE, or DCI.

[0209] Figure 5 An example of a UE 500 according to aspects of this disclosure is described. UE 500 may include at least one processor 502 and at least one memory 504. Additionally, UE 500 may also include one or more of at least one controller 506 or at least one transceiver 508. The processor 502, memory 504, controller 506, or transceiver 508, or various combinations thereof, or various components thereof, may be examples of components for performing the aspects of this disclosure described herein. These components may be coupled via one or more interfaces (operably, communicatively, functionally, electronically, electrically).

[0210] Processor 502, memory 504, controller 506, or transceiver 508, or various combinations or components thereof, may be implemented in hardware (e.g., a circuit system). The hardware may include processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), or other programmable logic devices, or any combination thereof configured or otherwise supporting components for performing the functions described in this disclosure.

[0211] Processor 502 may include intelligent hardware devices (e.g., general-purpose processors, DSPs, CPUs, ASICs, FPGAs, or any combination thereof). In some embodiments, processor 502 may be configured to operate memory 504. In some other embodiments, memory 504 may be integrated into processor 502. Processor 502 may be configured to execute computer-readable instructions stored in memory 504 to cause UE 500 to perform various functions of this disclosure.

[0212] Memory 504 may comprise volatile or non-volatile memory. Memory 504 may store computer-readable, computer-executable code containing instructions that, when executed by processor 502, cause UE 500 to perform the various functions described herein. The code may be stored in a non-transitory computer-readable medium, such as memory 504 or another type of memory. Computer-readable media includes both non-transitory computer storage media and communication media, including any medium that facilitates the transfer of computer programs from one place to another. Non-transitory storage media may be any available medium accessible by a general-purpose or special-purpose computer.

[0213] In some implementations, processor 502 and memory 504 coupled to processor 502 may be configured to cause UE 500 to perform one or more of the functions described herein (e.g., instructions stored in memory 504 executed by processor 502). For example, processor 502 may support wireless communication at UE 500 according to the examples disclosed herein. UE 500 may be configured to support components for performing the methods described in the embodiments of this disclosure. In an embodiment, processor 502 may be configured to cause UE 500 to: select a set of channels for transmission via SL, wherein the transmission is one of: S-SSB transmission, SL transmission, or PSFCH transmission; and determine the availability of each channel within the set of channels by performing a type-independent multichannel access procedure or a type-dependent multichannel access procedure on the set of channels used for transmission.

[0214] Controller 506 manages the input and output signals of UE 500. Controller 506 can also manage peripheral devices not integrated into UE 500. In some implementations, controller 506 may utilize an operating system, such as... Or other operating systems. In some implementations, controller 506 may be implemented as part of processor 502.

[0215] In some embodiments, UE 500 may include at least one transceiver 508. In other embodiments, UE 500 may have more than one transceiver 508. Transceiver 508 may represent a wireless transceiver. Transceiver 508 may include one or more receiver chains 510, one or more transmitter chains 512, or a combination thereof.

[0216] Receiver chain 510 may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, receiver chain 510 may include one or more antennas for receiving signals over the air or a wireless medium. Receiver chain 510 may include at least one amplifier (e.g., a low-noise amplifier (LNA)) configured to amplify the received signal. Receiver chain 510 may include at least one demodulator configured to demodulate the received signal and obtain transmitted data by reversing the modulation technique applied during signal transmission. Receiver chain 510 may include at least one decoder for decoding the demodulated signal to receive the transmitted data.

[0217] Transmitter chain 512 can be configured to generate and transmit signals (e.g., control information, data, packets). Transmitter chain 512 may include at least one modulator for modulating data onto a carrier signal in preparation for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques, such as amplitude modulation (AM), frequency modulation (FM), or digital modulation schemes like phase shift keying (PSK) or quadrature amplitude modulation (QAM). Transmitter chain 512 may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over a wireless medium. Transmitter chain 512 may also include one or more antennas for transmitting the amplified signal into the air or a wireless medium.

[0218] Figure 6 An example of a processor 600 according to aspects of this disclosure is described. Processor 600 may be an example of a processor configured to perform various operations according to the examples described herein. Processor 600 may include a controller 602 configured to perform various operations according to the examples described herein. Processor 600 may optionally include at least one memory 604, which may be, for example, a layer 1 (L1), layer 2 (L2), or layer 3 (L3) cache. Additionally or alternatively, processor 600 may optionally include one or more arithmetic logic units (ALUs) 606. One or more of these components may be electronically communicated or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses).

[0219] Processor 600 may be a processor chipset and includes a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receive, acquire, retrieve, transmit, output, forward, store, determine, identify, access, write, read) according to the examples described herein. The processor chipset may include one or more cores and one or more caches (e.g., memory local to the processor chipset (e.g., processor 600) or included in the processor chipset, 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), and others)).

[0220] The controller 602 can be configured to manage and coordinate various operations of the processor 600 (e.g., signaling, receiving, acquiring, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, and reading) to enable the processor 600 to support various operations according to the examples described herein. For example, the controller 602 can operate as a control unit of the processor 600, generating control signals that manage the operation of various components of the processor 600. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating operation timing.

[0221] Controller 602 may be configured to fetch (e.g., fetch, retrieve, receive) instructions from memory 604 and determine subsequent instructions to be executed to enable processor 600 to support various operations according to the examples described herein. Controller 602 may be configured to track the memory addresses of instructions associated with memory 604. Controller 602 may be configured to decode instructions to determine the operations to be performed and the operands involved. For example, controller 602 may be configured to interpret instructions and determine control signals to be output to other components of processor 600 to enable processor 600 to support various operations according to the examples described herein. Alternatively or additionally, controller 602 may be configured to manage data flow within processor 600. Controller 602 may be configured to control data transfers between registers, ALU, and other functional units of processor 600.

[0222] Memory 604 may include one or more caches (e.g., memory or other memory local to or included in processor 600, such as RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc.). In some embodiments, memory 604 may reside within or on the processor chipset (e.g., locally to processor 600). In some other embodiments, memory 604 may reside outside the processor chipset (e.g., remotely from processor 600).

[0223] Memory 604 may store computer-readable, computer-executable code containing instructions that, when executed by processor 600, cause processor 600 to perform the various functions described herein. The code may be stored in a non-transitory computer-readable medium, such as system memory or another type of memory. Controller 602 and / or processor 600 may be configured to execute the computer-readable instructions stored in memory 604 to cause processor 600 to perform various functions. For example, processor 600 and / or controller 602 may be coupled to or coupled to memory 604, and processor 600, controller 602, and memory 604 may be configured to perform the various functions described herein. In some instances, processor 600 may include multiple processors, and memory 604 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 jointly configured to perform the various functions described herein.

[0224] One or more ALUs 606 may be configured to support various operations according to the examples described herein. In some embodiments, one or more ALUs 606 may reside within or on a processor chipset (e.g., processor 600). In some other embodiments, one or more ALUs 606 may reside outside the processor chipset (e.g., processor 600). One or more ALUs 606 may perform one or more computations on data, such as addition, subtraction, multiplication, and division. For example, one or more ALUs 606 may receive input operands and opcodes, which determine the operation to be performed. One or more ALUs 606 are configured with various logic and arithmetic circuitry, including adders, subtractors, shifters, and logic gates, to process and manipulate data according to the operation. Alternatively, one or more ALU 606s may support logical operations such as AND, OR, XOR, NOR, and NAND, enabling one or more ALU 606s to handle conditional operations, comparisons, and bitwise operations.

[0225] Processor 600 may support wireless communication according to the examples disclosed herein. Processor 600 may be configured or operable to support components for performing the methods described in the embodiments of this disclosure. In an embodiment, controller 602 may cause processor 600 to: select a set of channels for transmission via SL, wherein the transmission is one of: S-SSB transmission, SL transmission, or PSFCH transmission; and determine the availability of each channel within the set of channels by performing a type-independent multichannel access procedure or a type-dependent multichannel access procedure on the set of channels used for transmission.

[0226] Figure 7An example of BS 700 according to aspects of this disclosure is described. BS 700 may include at least one processor 702 and at least one memory 704. Additionally, BS 700 may also include one or more of at least one controller 706 or at least one transceiver 708. Processor 702, memory 704, controller 706, or transceiver 708, or various combinations thereof, or various components thereof, may be examples of components for performing the aspects of this disclosure described herein. These components may be coupled via one or more interfaces (operably, communicatively, functionally, electronically, electrically).

[0227] Processor 702, memory 704, controller 706, or transceiver 708, or various combinations or components thereof, may be implemented in hardware (e.g., a circuit system). The hardware may include processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), or other programmable logic devices, or any combination thereof configured or otherwise supporting components for performing the functions described in this disclosure.

[0228] Processor 702 may include intelligent hardware devices (e.g., general-purpose processors, DSPs, CPUs, ASICs, FPGAs, or any combination thereof). In some embodiments, processor 702 may be configured to operate memory 704. In some other embodiments, memory 704 may be integrated into processor 702. Processor 702 may be configured to execute computer-readable instructions stored in memory 704 to cause BS 700 to perform various functions of this disclosure.

[0229] Memory 704 may comprise volatile or non-volatile memory. Memory 704 may store computer-readable, computer-executable code containing instructions that, when executed by processor 702, cause BS 700 to perform the various functions described herein. The code may be stored in a non-transitory computer-readable medium, such as memory 704 or another type of memory. Computer-readable media include both non-transitory computer storage media and communication media, encompassing any medium that facilitates the transfer of computer programs from one place to another. Non-transitory storage media may be any available medium accessible by a general-purpose or special-purpose computer.

[0230] In some embodiments, processor 702 and memory 704 coupled to processor 702 may be configured to cause BS 700 to perform one or more of the functions described herein (e.g., instructions stored in memory 704 are executed by processor 702). For example, processor 702 may support wireless communication at BS 700 according to the examples disclosed herein. BS 700 may be configured to support components for performing the methods described in embodiments of this disclosure. In an embodiment, processor 702 may be configured to cause BS 700 to: transmit configuration information to UE for multi-channel access via SL, wherein the configuration information indicates: a CAPC threshold for causing UE to select a channel to perform S-SSB transmission; or a COT duration threshold for causing UE to determine whether to perform sidelink transmission on the channel.

[0231] Controller 706 manages the input and output signals of BS 700. Controller 706 can also manage peripheral devices not integrated into BS 700. In some implementations, controller 706 may utilize an operating system, such as... Or other operating systems. In some implementations, controller 706 may be implemented as part of processor 702.

[0232] In some embodiments, the BS 700 may include at least one transceiver 708. In other embodiments, the BS 700 may have more than one transceiver 708. The transceiver 708 may represent a wireless transceiver. The transceiver 708 may include one or more receiver chains 710, one or more transmitter chains 712, or a combination thereof.

[0233] Receiver chain 710 may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, receiver chain 710 may include one or more antennas for receiving signals over the air or a wireless medium. Receiver chain 710 may include at least one amplifier (e.g., a low-noise amplifier (LNA)) configured to amplify the received signal. Receiver chain 710 may include at least one demodulator configured to demodulate the received signal and obtain transmitted data by reversing the modulation technique applied during signal transmission. Receiver chain 710 may include at least one decoder for decoding the demodulated signal to receive the transmitted data.

[0234] Transmitter chain 712 can be configured to generate and transmit signals (e.g., control information, data, packets). Transmitter chain 712 may include at least one modulator for modulating data onto a carrier signal in preparation for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques, such as amplitude modulation (AM), frequency modulation (FM), or digital modulation schemes like phase shift keying (PSK) or quadrature amplitude modulation (QAM). Transmitter chain 712 may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over a wireless medium. Transmitter chain 712 may also include one or more antennas for transmitting the amplified signal into the air or a wireless medium.

[0235] The description herein is provided to enable those skilled in the art to make or use this disclosure. Those skilled in the art will understand that various modifications to this disclosure are possible, and that the general principles defined herein may be applied to other variations without departing from the scope of this disclosure. Therefore, this disclosure is not limited to the examples and designs described herein, but should be given the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A user equipment (UE) for wireless communication, comprising: At least one memory; and At least one processor, coupled to and configured to enable the UE to: To select a set of channels for transmission via the sidelink SL, wherein the transmission is one of the following: sidelink synchronization signal block (S-SSB) transmission, SL transmission, or physical sidelink feedback channel (PSFCH) transmission; and The availability of each channel within the set of channels is determined by performing a type-independent or type-dependent multichannel access procedure on the set of channels used for the transmission.

2. The UE according to claim 1, wherein in the type-independent multichannel access procedure: The channel access procedure is executed independently for each channel within the set of channels; and The channel access type on each channel within the group of channels is determined based on whether the channel is within the Channel Occupancy Time (COT) or whether the channel is within the COT shared with the UE for performing the transmission.

3. The UE according to claim 1, wherein in the type-dependent multichannel access procedure: If at least one channel in the set of channels is outside the COT (Cross-Operated Access Control) mechanism, a Type 1 dynamic channel access procedure is performed on the first channel within the at least one channel, and a Type 2 dynamic channel access procedure is performed on each of the remaining channels in the set of channels other than the first channel; or When all channels in the set of channels are within the COT, the Type 2 dynamic channel access procedure is executed independently for each channel in the set of channels.

4. The UE of claim 1, wherein, in the case that the transmission is an S-SSB transmission, in order to select the set of channels, the at least one processor is configured to cause the UE to: Randomly select a channel within the frequency range; Prefer anchor channel; or In the case of the type-dependent multichannel access procedure, at least one channel other than COT is preferentially selected.

5. The UE of claim 1, wherein, in order to execute the type-independent multichannel access procedure for S-SSB transmission, the at least one processor is configured to cause the UE to: The channel access type on each channel is determined individually based on whether the target S-SSB timing on each channel within the group of channels is within the COT; and The channel access procedure is performed for each channel based on the channel access type determined individually for each channel within the set of channels.

6. The UE of claim 1, wherein, in the case that the transmission is an S-SSB transmission, the at least one processor is further configured to cause the UE to: If the anchor channel within the set of channels is determined to be available, the anchor channel is selected to perform the S-SSB transmission; or In the event that no anchor channel is available: The S-SSB transmission is performed by randomly selecting a channel from all available channels within the set of channels. The S-SSB transmission is performed by randomly selecting a channel from at least one available channel within the set of channels and within the COT. Select all available channels within the set of channels to perform the S-SSB transmission; The S-SSB transmission is performed by selecting all available channels within the set of channels and within the COT; or The S-SSB transmission is performed by selecting a channel from at least one channel within the set of channels and within the COT, based on the Channel Access Priority Class (CAPC) corresponding to the COT.

7. The UE of claim 1, wherein, in the case of executing the type-independent multichannel access procedure for SL transmission, in order to select the set of channels, the at least one processor is configured to cause the UE to: At least when the SL transmission is intended for a UE to initiate the COT, a channel within the COT shared with the UE is preferentially selected.

8. The UE of claim 1, wherein, in order to execute the type-independent multichannel access procedure for SL transmission, the at least one processor is configured to cause the UE to: The channel access type on each channel is individually determined based on whether each channel in the set of channels is within a COT shared by the UE for performing at least one SL transmission and whether the SL transmission is intended at least for a UE to initiate the COT; and The channel access procedure is performed for each channel based on the channel access type determined individually for each channel within the set of channels.

9. The UE of claim 1, wherein, in the case that the transmission is an SL transmission, the at least one processor is further configured to cause the UE to: Select all channels that are determined to be available to perform the SL transmission.

10. The UE of claim 1, wherein, in the case that the transmission is a PSFCH transmission, in order to select the set of channels, the at least one processor is configured to cause the UE to: The selected PSFCH resource corresponds to the channel to which the UE transmits SL transmissions of Hybrid Automatic Repeat Request (HARQ) feedback.

11. The UE of claim 1, wherein, in order to execute the type-independent multichannel access procedure for PSFCH transmission, the at least one processor is configured to cause the UE to: The channel access type on each channel is individually determined based on whether each channel in the set of channels is within a COT shared with the UE for performing PSFCH transmissions and whether at least one of the PSFCH transmissions is intended for a UE to initiate the COT; and The channel access procedure is performed for each channel based on the channel access type determined individually for each channel within the set of channels.

12. The UE of claim 1, wherein, in the case that the transmission is a PSFCH transmission, the at least one processor is further configured to cause the UE to: Select all channels identified as available to perform PSFCH transmission; or If the UE is unable to transmit PSFCH on all channels that are determined to be available, the PSFCH transmission will be dropped according to the priority of the corresponding SL transmission.

13. The UE of claim 1, wherein, in order to execute the type-dependent multichannel access procedure for S-SSB transmission, the at least one processor is configured to cause the UE to: If at least one channel in the set of channels is outside the COT: Select the first channel within the at least one channel; Perform a Type 1 dynamic channel access procedure on the first channel to determine whether an S-SSB opportunity in the first channel is available for S-SSB transmission; and Before the start point of the S-SSB timing in the first channel, perform a Type 2 dynamic channel access procedure for each remaining channel in the group of channels other than the first channel; or When all channels in the set of channels are within the COT, the Type 2 dynamic channel access procedure is executed independently for each channel in the set of channels.

14. The UE of claim 1, wherein when the type-dependent multichannel access procedure is executed for SL transmission, in order to select the set of channels, the at least one processor is configured such that the UE: preferentially selects at least one channel other than COT.

15. The UE of claim 1, wherein, in order to execute the type-dependent multichannel access procedure for SL transmission, the at least one processor is configured to cause the UE to: If at least one channel in the set of channels is outside the COT: Select the first channel within the at least one channel; Execute a Type 1 dynamic channel access procedure on the first channel; and Before the SL transmission on the first channel, a Type 2 dynamic channel access procedure is performed on each of the remaining channels in the group of channels other than the first channel; or When all channels in the set of channels are within the COT, the Type 2 dynamic channel access procedure is executed independently for each channel in the set of channels.

16. The UE of claim 1, wherein when the type-dependent multichannel access procedure is executed for SL transmission, the at least one processor is further configured to cause the UE to: If a channel is determined to be available within the COT, the decision to perform the SL transmission on that channel is based on the remaining COT duration.

17. The UE of claim 1, wherein, in order to execute the type-dependent multichannel access procedure for PSFCH transmission, the at least one processor is configured to cause the UE to: If at least one channel in the set of channels is outside the COT: Select the first channel within the at least one channel; A Type 1 dynamic channel access procedure is executed on the first channel to determine whether the PSFCH timing in the first channel can be used for PSFCH transmission; and Before the start point of the PSFCH timing in the first channel, perform a Type 2 dynamic channel access procedure for each remaining channel in the group of channels other than the first channel; or When all channels in the set of channels are within the COT, the Type 2 dynamic channel access procedure is executed independently for each channel in the set of channels.

18. A processor for wireless communication, comprising: At least one controller, coupled to at least one memory and configured to enable the processor to: To select a set of channels for transmission via the sidelink SL, wherein the transmission is one of the following: sidelink synchronization signal block (S-SSB) transmission, SL transmission, or physical sidelink feedback channel (PSFCH) transmission; and The availability of each channel within the set of channels is determined by performing a type-independent or type-dependent multichannel access procedure on the set of channels used for the transmission.

19. A base station (BS) for wireless communication, comprising: At least one memory; and At least one processor, coupled to the at least one memory and configured to enable the BS to: The configuration information for multi-channel access via sidelink SL is transmitted to the user equipment (UE), wherein the configuration information indicates: The channel access priority category CAPC threshold used to enable the UE to select a channel to perform sidelink synchronization signal block S-SSB transmission; or The Channel Occupancy Time (COT) duration threshold is used to enable the UE to determine whether to perform a sidelink transmission on the channel.

20. A method performed by a user equipment (UE), comprising: To select a set of channels for transmission via the sidelink SL, wherein the transmission is one of the following: sidelink synchronization signal block (S-SSB) transmission, SL transmission, or physical sidelink feedback channel (PSFCH) transmission; and The availability of each channel within the set of channels is determined by performing a type-independent or type-dependent multichannel access procedure on the set of channels used for the transmission.

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