Channel access priority class design for unlicensed sidelink

Abstract

The present disclosure relates to a method performed by a first user equipment (UE). The method includes determining, by a first UE, a channel access priority class (CAPC) for transmission to a second UE over a sidelink interface; and performing a listen before talk procedure on the sidelink interface based on the determined CAPC.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application No. 63 / 407,580, filed on September 16, 2022, entitled “CHANNEL ACCESS PRIORITY CLASS DESIGN FOR SIDELINK UNLICENSED,” which is incorporated herein by reference in its entirety. Background Art

[0003] Wireless communication networks provide integrated communication platforms and telecommunication services to wireless user devices. Example telecommunication services include telephone, data (e.g., voice, audio and / or video data), messaging, Internet access and / or other services. Wireless communication networks have wireless access nodes that exchange wireless signals with wireless user devices using wireless network protocols (such as protocols described in various telecommunication standards promulgated by the Third Generation Partnership Project (3GPP)). Example wireless communication networks include time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal frequency division multiple access (OFDMA) networks, long term evolution (LTE) and fifth generation new radio (5G NR). Wireless communication networks use technologies such as OFDM, multiple input multiple output (MIMO), advanced channel coding, massive MIMO, beamforming and / or other features to facilitate mobile broadband services.

[0004] In some wireless communication networks, a user equipment (UE) can communicate directly (e.g., without a radio access network as an intermediary) with another UE using so-called sidelink communications. During sidelink communications, the transmitting UE determines a subset of available sidelink resources for communicating with the receiving UE based on a resource allocation scheme. Existing protocols support sidelink communications using two different resource allocation schemes. In a first scheme, referred to as Mode 1 resource allocation ("Mode 1"), sidelink resources are allocated by an access node to in-coverage UEs. In a second scheme, referred to as Mode 2 resource allocation ("Mode 2"), the transmitting UE selects sidelink resources from available sidelink resources (e.g., a sidelink resource pool). Summary of the invention

[0005] The present disclosure describes techniques for channel access priority class (CAPC) selection for transmissions on an unlicensed sidelink. The disclosed techniques are designed to take into account features specific to the sidelink and are therefore different from existing CAPC selection mechanisms (e.g., for interfaces other than the sidelink). In some examples, new mappings are defined that relate the PC55QI (PQI) used for sidelink transmissions to the CAPC used for transmission. Other mappings that facilitate CAPC selection for the sidelink are also defined, including mappings between sidelink logical channel (SL-LCH) priorities and CAPCs and between L1 priorities and CAPCs. Various rules for CAPC selection based on the logical channel used for sidelink transmissions, the sidelink bearer used for transmission (e.g., SL-SRB or SL-DRB), and / or the type of data included in the transmission are also defined.

[0006] In general, in a first aspect, a method to be performed by a first user equipment (UE) includes determining, by the first UE, a CAPC for transmission to a second UE over a sidelink interface; and performing a listen-before-talk procedure on the sidelink interface based on the determined CAPC.

[0007] Generally speaking, in a second aspect that can be combined with the first aspect, determining the CAPC for the transmission includes: determining a PC5 5QI (PQI) for transmission to a second UE via a side link interface; and determining the CAPC for the transmission based on the PQI for the transmission and a mapping between the PQI and the CAPC.

[0008] Generally speaking, in a third aspect which may be combined with any of the first or second aspects, a PQI for a transmission is determined based on a quality of service (QoS) associated with the transmission.

[0009] Generally speaking, in a fourth aspect which can be combined with any one of the first to third aspects, the transmission is associated with a non-standardized QoS, and determining the PQI for the transmission includes: determining a standardized QoS based on the non-standardized QoS; and using the PQI associated with the standardized QoS as the PQI for the transmission.

[0010] Generally speaking, in the fifth aspect which can be combined with any aspect from the first to the fourth aspect, determining the CAPC used for the transmission includes: determining a sidelink logical channel used for transmission to a second UE through a sidelink interface; and determining the CAPC used for transmission based on the sidelink logical channel used for transmission and a mapping between the sidelink logical channel and the CAPC.

[0011] Generally, in a sixth aspect which may be combined with any one of the first to fifth aspects, the mapping associates a physical sidelink feedback channel (PSFCH) or a physical sidelink control channel (PSCCH) with a highest priority CAPC.

[0012] Generally speaking, in the seventh aspect which can be combined with any one of the first to sixth aspects, determining the CAPC used for the transmission includes: determining the type of data included in the transmission to the second UE through the side link interface; and determining the CAPC used for the transmission based on the type of data included in the transmission and the mapping between the type of data transmission and the CAPC.

[0013] Generally, in an eighth aspect which may be combined with any one of the first to seventh aspects, the mapping associates a side link synchronization signal block (SL-SSB) with a highest priority CAPC.

[0014] Generally speaking, in a ninth aspect which may be combined with any of the first to eighth aspects, a mapping associates at least one type of medium access control (MAC) control element (CE) with a highest priority CAPC or a lowest priority CAPC.

[0015] Generally, in a tenth aspect which may be combined with any of the first to ninth aspects, the mapping associates a fill buffer status report (BFR) with a lowest priority CAPC.

[0016] Generally speaking, in the eleventh aspect which can be combined with any aspect from the first to the tenth aspect, determining the CAPC used for the transmission includes: determining a bearer for transmission to the second UE through the side link interface; and determining the CAPC used for the transmission based on the bearer used for the transmission and a mapping between the bearer and the CAPC.

[0017] Generally, in a twelfth aspect which may be combined with any one of the first to eleventh aspects, the mapping associates a sidelink signaling radio bearer 0 (SL-SRBO), SL-SRB1 or SL-SRB4 with a highest priority CAPC.

[0018] Generally, in a thirteenth aspect which may be combined with any one of the first to twelfth aspects, the mapping associates a sidelink signaling radio bearer 2 (SL-SRB2) with a highest priority CAPC or a configured CAPC.

[0019] Generally speaking, in the fourteenth aspect which can be combined with any one of the first to thirteenth aspects, the transmission is a SL-SRB2, SL-SRB3 or a sidelink data radio bearer (SL-DRB), and the method includes receiving an indication of a CAPC to be used for the transmission from an access node.

[0020] Generally speaking, in the fifteenth aspect which can be combined with any one of the first to fourteenth aspects, the bearer used for the transmission is SL-SRB2, SL-SRB3 or SL-DRB, and when the transmission includes one or more MAC CEs, the highest priority CAPC among the one or more MAC CEs is used as the CAPC for the transmission.

[0021] Generally speaking, in the sixteenth aspect which can be combined with any one of the first to fifteenth aspects, the bearer used for the transmission is SL-SRB2, SL-SRB3 or SL-DRB, and when the transmission includes one or more of SRB0 service data units (SDUs), SRB1 SDUs, SRB2 SDUs or SRB4 SDUs, the highest priority CAPC is used as the CAPC for the transmission.

[0022] Generally speaking, in the seventeenth aspect which can be combined with any one of the first to sixteenth aspects, the bearer used for the transmission is SL-SRB2, SL-SRB3 or SL-DRB, and when the transmission includes one or more SL-SRB3 SDUs, the highest priority CAPC among the one or more SL-SRB3 SDUs is used as the CAPC for the transmission.

[0023] Generally speaking, in the eighteenth aspect which can be combined with any aspect from the first to the seventeenth aspect, determining the CAPC for the transmission includes: determining the logical channel priority for the transmission; and determining the CAPC for the transmission based on the logical channel priority for the transmission and a mapping between the side link logical channel (SL-LCH) priority and the CAPC.

[0024] Generally speaking, in the nineteenth aspect which can be combined with any one of the first to eighteenth aspects, determining the CAPC for the transmission includes: determining a layer 1 priority for the transmission; and determining the CAPC for the transmission based on the layer 1 priority for the transmission and a mapping between the layer 1 priority and the CAPC.

[0025] Generally speaking, in a twentieth aspect that may be combined with any of the first to nineteenth aspects, the transmission is a configured authorized transmission, and the CAPC for the transmission is determined based on a configured authorized configuration index.

[0026] Generally speaking, in a 21st aspect which may be combined with any of the 1st to 20th aspects, a CAPC for transmission is determined based at least in part on how long data for transmission has been queued in a buffer or how much data is queued in the buffer.

[0027] Generally speaking, in a twenty-second aspect which may be combined with any one of the first to twenty-first aspects, a CAPC used for transmission is adjusted to a higher priority CAPC when the transmission is a retransmission.

[0028] Generally speaking, in a twenty-third aspect that may be combined with any one of the first to twenty-second aspects, the method includes sending a transmission to a second UE over a sidelink interface after performing a listen-before-talk procedure based on the determined CAPC.

[0029] Generally speaking, in a twenty-fourth aspect which may be combined with any of the first to twenty-third aspects, the sending includes an indication of the determined CAPC.

[0030] In general, in a 25th aspect which may be combined with any one of the first to 24th aspects, the method includes receiving an indication of a CAPC to be used for the transmission from the second UE.

[0031] Generally speaking, in a twenty-sixth aspect which may be combined with any of the first to twenty-fifth aspects, performing a listen-before-talk process based on the determined CAPC includes adjusting one or more listen-before-talk parameters based on the determined CAPC.

[0032] Generally speaking, in one aspect, a non-transitory computer storage medium stores instructions that, when executed by at least one processor, cause the at least one processor to perform any one of the first to twenty-sixth aspects.

[0033] In general, in one aspect, a system includes at least one processor and at least one storage device storing instructions executable by the at least one processor to cause the at least one processor to perform any one of the first to twenty-sixth aspects.

[0034] Generally speaking, in one aspect, a UE includes at least one processor and at least one storage device storing instructions executable by the at least one processor to cause the at least one processor to perform any one of the first to twenty-sixth aspects.

[0035] Generally speaking, in one aspect, a baseband processor is configured to perform any of aspects 1 to 26. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 An example wireless network according to some implementations is illustrated.

[0037] Figure 2 A flow chart illustrating channel access priority class (CAPC) selection for an unlicensed side link according to some implementations is illustrated.

[0038] Figure 3 An example user equipment (UE) according to some implementations is illustrated.

[0039] Figure 4 Example access nodes according to some implementations are illustrated.

[0040] Like reference numbers and designations in the various drawings indicate like elements. DETAILED DESCRIPTION

[0041] In Release 18 of the 3rd Generation Partnership Project (3GPP) technical standards, one of the areas of research and development is a sidelink interface operating in an unlicensed spectrum (also referred to as an "unlicensed side link"). Specifically, the research and development includes a channel access mechanism, a sidelink resource reservation process, a physical channel design framework, and a sidelink physical channel structure and process for an unlicensed side link. One of the advantages of the unlicensed side link is the ability to meet the growing demand for wireless data services. Additionally, the unlicensed side link can achieve better latency (e.g., quality of service or QoS) from the perspective of the user equipment (UE) than the latency that can be achieved through Uu interference. In addition, some use cases and device types may particularly benefit from the unlicensed side link. Example use cases include home networks, personal networks, industrial networks, etc., and example device types include Internet of Things (IoT) devices, wearable devices, relay devices, etc.

[0042] During sidelink communication, the transmitting UE (TX UE) uses a set of allocated sidelink resources to communicate directly with the receiving UE (RXUE). Some wireless communication systems (such as those implemented according to 3GPP technical standards) support two sidelink resource allocation schemes. In the first scheme, which is called mode 1 resource allocation ("mode 1"), the access node allocates sidelink resources to the UEs within the coverage area. In the second scheme, which is called mode 2 resource allocation ("mode 2"), the transmitting UE selects the sidelink resource from the available sidelink resources (e.g., a sidelink resource pool) without involving the access node.

[0043] Like other communications on the unlicensed spectrum, the unlicensed side link may use a listen-before-talk (LBT) process to access the channel. During LBT, the TX UE listens or senses the channel to determine whether the channel is idle or busy. If the channel is determined to be idle, the TX UE may perform a transmission to the RX UE. If no channel is idle, the TX UE will wait for the contention window to perform LBT again. In order to promote quality of service (QoS), one or more LBT parameters may be adapted based on a channel access priority class (CAPC) associated with the transmission. For example, if a transmission is associated with a higher CAPC priority (e.g., a lower CAPC number), one or more LBT parameters (such as a sensing interval, a contention window size, and / or a channel occupancy time) may be adapted to increase the likelihood of acquiring a channel to perform a transmission.

[0044] In New Radio Unlicensed (NR-U), the CAPC for transmission is specified by mapping between a 5G QoS indicator (5QI) that identifies which QoS category the transmission belongs to and four different CAPCs, as shown in the following table. In addition, the 3GPP technical standard for NR-U specifies various rules for determining the CAPC for transmission, including: the CAPC for signaling radio bearer 0 (SRB0), SRB1, and SRB3 is the highest priority CAPC; the CAPC for SRB2 and data radio bearer (DRB) is configurable via downlink control information (DCI), the CAPC for medium access control (MAC) control element (CE) is the highest priority CAPC, except for filling buffer status report (BSR) and codec adaptation (which has the lowest priority CAPC); and if more than one different QoS flow is multiplexed in one DRB, the access node (e.g., gNodeB) considers the 5QI of all its QoS flows to determine the CAPC.

[0045] CAPC 5Q 1 1,3,51,3,5,65,66,67,69,70,79,80,82,83,84,85 2 2,7,71 3 4,6,8,9,72,73,74,76 4 -

[0046] Currently, there is no means defined in the 3GPP technical standards for determining the CAPC for transmissions on the unlicensed side link (SL-U). In addition, the fundamental differences between SL-U and NR-U, such as the presence of different SRBs and DRBs, physical sidelink feedback channel (PSFCH), sidelink synchronization signal blocks (SL-SSBs) and other sidelink-specific control signaling, and the need for bidirectionality of CAPC on the side link (because CAPC is not managed by the access node), make the CAPC selection rules used for NR-U and other interfaces not directly applicable to SL-U.

[0047] The present disclosure describes techniques for CAPC selection for transmissions on an unlicensed sidelink. The disclosed techniques are designed to take into account features specific to the sidelink and are therefore different from existing CAPC selection mechanisms (e.g., for interfaces other than the sidelink). In some examples, new mappings are defined that relate the PC5 5QI (PQI) for sidelink transmissions to the CAPC used for transmission. Other mappings that facilitate CAPC selection for the sidelink are also defined, including mappings between sidelink logical channel (SL-LCH) priorities and CAPCs and between L1 priorities and CAPCs. Various rules for CAPC selection based on the logical channel used for sidelink transmissions, the sidelink bearer used for transmission (e.g., SL-SRB or SL-DRB), and / or the type of data included in the transmission are also defined.

[0048] Figure 1 An example communication system 100 including sidelink communication according to some implementations is illustrated. Note that Figure 1 The system is just one example of a possible system, and features of the present disclosure may be implemented in other wireless communication systems.

[0049] The following description is provided for an example communication system operating in conjunction with a fifth generation (5G) network provided by the 3GPP technical specification. However, the example implementation is not limited in this regard, and the described examples may be applied to other networks that may benefit from the principles described herein, such as 3GPP Long Term Evolution (LTE) networks, Wi-Fi, etc. In addition, other types of communication standards are also possible, including future 3GPP systems (e.g., sixth generation (6G)). Although various aspects may be described herein using terms typically associated with 5G NR, various aspects of the present disclosure may be applied to other systems, such as 3G, 4G, and / or systems after 5G (e.g., 6G).

[0050] As shown, the communication system 100 includes a plurality of user equipments. More specifically, the communication system 100 includes two UEs 105 (UE 105-1 and UE 105-2 are collectively referred to as "UE 105" or "UEs 105"), two base stations 110 (base stations 110-1 and base stations 110-2 are collectively referred to as "base stations 110" or "base stations 110"), two cells 115 (cells 115-1 and cells 115-2 are collectively referred to as "cells 115" or "cells 115"), and one or more servers 135 in a core network (CN) 140 connected to the Internet 145.

[0051] In some implementations, UE 105 may communicate directly with base station 110 via links 120 (links 120-1 and 120-2 are collectively referred to as "a link 120" or "links 120"), which utilize a direct interface with the base station (referred to as a "Uu interface"). Each of links 120 may represent one or more channels. Links 120 are illustrated as air interfaces that implement communication coupling and may conform to cellular communication protocols, such as GSM protocols, CDMA network protocols, UMTS protocols, 3GPP LTE protocols, Advanced Long Term Evolution (LTE-A) protocols, LTE-based unlicensed spectrum access (LTE-U), 5G protocols, NR protocols, NR-based unlicensed spectrum access (NR-U) protocols, and / or any other communication protocols discussed herein.

[0052] As shown, some user equipments may be able to communicate directly with each other, for example, without intermediate infrastructure equipment (such as base station 110-1). In this example, UE 105-1 may communicate directly with UE 105-2. Similarly, UE 105-2 may communicate directly with UE 105-1. This peer-to-peer communication may utilize a "side link" interface such as a PC5 interface. In some specific implementations, the PC5 interface supports direct cellular communication between user equipments (e.g., between UE 105), while the Uu interface supports cellular communication with infrastructure equipment (such as a base station). For example, UE 105 may use the PC5 interface for radio resource control (RRC) signaling exchange between UEs. The PC5 / Uu interface is used only as an example, and PC5 as used herein may represent various other possible wireless communication technologies that allow direct side link communication between user equipments, while Uu may represent cellular communication performed between user equipments and infrastructure equipment (such as a base station).

[0053] In order to transmit / receive data to / from one or more base stations 110 or UE 105, UE 105 may include a transmitter / receiver (or alternatively, a transceiver), a memory, one or more processors, and / or other similar components that enable UE 105 to operate according to one or more wireless communication protocols and / or one or more cellular communication protocols. UE 105 may have multiple antenna elements that enable UE 105 to maintain multiple links 120 and / or side links 125 to transmit / receive data to / from multiple base stations 110 and / or multiple UEs 105. For example, as Figure 1 As shown, UE 105 - 1 may be connected to base station 110 - 1 via link 120 and simultaneously connected to UE 105 - 2 via side link 125 .

[0054] In some implementations, one or more sidelink radio bearers may be established on the sidelink 125. The sidelink radio bearers may include signaling radio bearers (SL-SRBs) and / or data radio bearers (SL-DRBs). The signaling radio bearers may be of different types, including SL-SRB0, SL-SRB1, SL-SRB2, SL-SRB3, and SL-SRB4.

[0055] The PC5 interface may alternatively be referred to as a sidelink interface and may include one or more logical channels, including but not limited to a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), a physical sidelink discovery channel (PSDCH), a physical sidelink broadcast channel (PSBCH), a physical sidelink feedback channel (PSFCH) and / or any other similar communication channel. The PSFCH carries feedback related to the success or failure reception of the sidelink transmission. The PSSCH may be scheduled by the sidelink control information (SCI) carried in the sidelink PSCCH. In some examples, the sidelink interface may operate on an unlicensed spectrum (e.g., in an unlicensed 5 GHz (GHz) and 6 GHz band) or a (licensed) shared spectrum.

[0056] In one example, the sidelink interface implements vehicle-to-everything (V2X) communications. V2X communications may, for example, follow the 3GPP Cellular V2X (C-V2X) specification, or follow one or more other or subsequent standards, whereby vehicles and other devices and network entities may communicate. V2X communications may utilize both long-range (e.g., cellular) communications and short-range to medium-range (e.g., non-cellular) communications. V2X communications with cellular capabilities may be referred to as cellular V2X (C-V2X) communications. C-V2X systems may use various cellular radio access technologies (RATs), such as 4G LTE or 5G NR RAT (or RATs after 5G, e.g., 6G RAT). Certain LTE standards available in V2X systems may be referred to as LTE-Vehicle (LTE-V) standards. As used herein in the context of a V2X system, and as defined above, the term "user equipment" may generally refer to a device associated with a mobile participant or traffic participant in a V2X system, for example, a mobile (capable of moving) communication device such as a vehicle, a pedestrian user equipment (PUE) device, and a roadside unit (RSU).

[0057] In some implementations, the UEs 105 may be physical hardware devices capable of running one or more applications, accessing network services via one or more radio links 120 with corresponding base stations 110 (also referred to as “serving” base stations), and communicating with each other via side links 125. The links 120 may allow the UEs 105 to send and receive data from the base stations 110 providing the links 120. The side links 125 may allow the UEs 105 to send and receive data with each other. The side links 125 between the UEs 105 may include one or more channels for transmitting information from the UE 105-1 to the UE 105-2 (or vice versa) and / or between the UE 105 and a UE-type RSU (or vice versa).

[0058] In some implementations, base stations 110 can communicate with each other over a backhaul connection 130, and can communicate with one or more servers 135 within CN 140 over another backhaul connection 133. The backhaul connection can be a wired and / or wireless connection.

[0059] In some implementations, UE 105 is configured to use a resource pool for sidelink communications. The sidelink resource pool may be divided into multiple time slots, frequency channels, and frequency subchannels. In some examples, UE 105 is synchronized and performs sidelink transmissions aligned with time slot boundaries. It may be desirable for the UE to select several time slots and subchannels for transmission of a transmission block. In some examples, the UE may use different subchannels to transmit a transmission block across multiple time slots within its own resource selection window.

[0060] In some implementations, the base station 110 may configure a special exception resource pool for the UE 105. The special exception resource pool includes resources that the UE 105 can use in special exception situations such as radio link failure (RLF). The special exception resource pool may include resources selected based on random resource allocation.

[0061] In some implementations, the communication system 100 supports different broadcast types, including unicast, broadcast, and groupcast (or multicast) communications. Unicast refers to direct communication between two UEs. Broadcast refers to communication broadcasted by a single UE to multiple other UEs. Groupcast refers to communication transmitted from a single UE to a set of UEs that meet a certain condition (e.g., as members of a specific group).

[0062] In some implementations, a first UE (e.g., UE 105-1) is configured to perform CAPC selection for sidelink transmission to a second UE (e.g., UE 105-2) via sidelink interface 125. Based on the determined CAPC, the first UE is configured to perform a listen-before-talk procedure on sidelink interface 125 (e.g., on a channel of sidelink interface 125) prior to transmission to the second UE. For purposes of this disclosure, a UE that is initiating communication with another UE is referred to as a TX UE, and a UE that is receiving the communication is referred to as an RX UE. For example, UE 105-1 may be a TX UE, and UE 105-2 may be an RX UE. In addition, although Figure 1 It is illustrated that a single TX UE communicates with a single RX UE, but the TX UE may communicate with more than one RX UE via a side link.

[0063] Figure 2 A process 200 for CAPC selection according to some specific implementations is illustrated. The process 200 may be implemented by a TX UE that is transmitting (or scheduled to transmit) a sidelink communication to a RX UE. The process 200 may be implemented by a TX UE operating in any RRC state (including idle, inactive, connected, or out of coverage) and transmitting to a RX UE. In addition, the process 200 may be implemented by a TX UE that is using a mode 1 resource allocation scheme or a mode 2 resource allocation scheme.

[0064] Initially, the TX UE determines to perform a transmission (e.g., data transmission) to the RX UE via the side link interface. Then, the TX UE determines a CAPC for transmission to the RX UE via the side link interface (202). In some implementations, the CAPC for transmission is determined based on a mapping between a PQI and a CAPC. For example, a mapping may be defined by a mapping table that relates a PQI to one of four CAPCs included in a 3GPP technical standard (and / or other CAPCs). Such a mapping may be specified in a 3GPP technical standard and known to the TX UE and the RX UE.

[0065] To determine the CAPC for a transmission based on the mapping, the TX UE may first determine the PQI for the transmission to the RX UE. For example, the TX UE may determine the PQI for the transmission based on the QoS associated with the transmission. If the transmission is associated with a non-standardized QoS, the TX UE may determine a standardized QoS that most closely matches the non-standardized QoS and use the PQI associated with the standardized QoS as the PQI for the transmission. In some implementations, the TX UE may receive an indication of the PQI for the transmission from, for example, the RX UE or a network node. Once the PQI for the transmission is determined, the TX UE may access a mapping between the PQI and the CAPC and use the mapping to identify the CAPC for the transmission (e.g., by performing a lookup in the mapping using the PQI).

[0066] In some examples, the TX UE determines a CAPC for a transmission to the RX UE based on one or more rules or mappings that specify a CAPC based on a logical channel (or logical channel group) used for a sidelink transmission, a sidelink bearer (e.g., SL-SRB or SL-DRB) used for the transmission, and / or a type of data included in the transmission, etc. For example, in some implementations, a rule or mapping may specify that a transmission on a PSFCH and / or PSCCH logical channel is associated with a highest priority CAPC, and the TX UE may determine a CAPC for the transmission based on the rule or mapping and a determination that the transmission to the RX UE is a PSFCH or PSCCH transmission.

[0067] In some implementations, the rule or mapping may specify that SL-SRB0, SL-SRB1, and SL-SRB4 are associated with the highest priority CAPC, and the TX UE may determine the CAPC for the transmission based on the rule or mapping and determining that the transmission to the RX UE uses SL-SRB0, SL-SRB1, or SL-SRB4. In some examples, the rule or mapping may also specify that SL-SRB2 is associated with the highest priority CAPC unless otherwise configured (e.g., by a network node), and the TX UE may determine the CAPC for the transmission based on the rule or mapping and determining that the transmission to the RX UE uses SL-SRB2.

[0068] In some implementations, a rule or mapping may specify that a SL-SSB transmission is associated with a highest priority CAPC, and the TX UE may determine a CAPC to use for the transmission based on the rule or mapping and a determination that the transmission to the RX UE is a SL-SSB transmission.

[0069] In some implementations, a rule or mapping may specify that a CAPC for at least one type of MAC-CE is associated with a highest priority CAPC, a lowest priority CAPC, or a CAPC configured, for example, by a network node. The TX UE may then determine a CAPC for the transmission based on the rule or mapping and determining that the transmission to the RX UE includes the at least one type of MAC-CE.

[0070] In some implementations, a rule or mapping may specify that the CAPC used to fill the BSR is associated with the lowest priority CAPC, or that the CAPC depends on the logical channel or logical channel group used to fill the BSR. The TX UE may then determine the CAPC to use for the transmission based on the rule or mapping and determining that the transmission to the RX UE includes filling the BSR (or based on the logical channel or logical channel group).

[0071] In some implementations, a rule or mapping may specify a CAPC for transmissions with SL-SRB3, SL-DRB, or (optionally) SL-SRB2. For example, a rule or mapping may specify that a network node provide a CAPC for transmissions to a TX UE in a sidelink grant (e.g., via DCI 3_0) or in a configured grant (e.g., via RRC). Such a rule may be applied only during Mode 1 resource allocation. When the TX UE operates in mode 2, or the network node does not provide CAPC in mode 1, the rule or mapping may specify that the TX UE determines the CAPC for transmission to the RX UE based on the following situations: if only sidelink MAC-CEs are present in the transmission to the RX UE, then use the highest priority CAPC in these sidelink MAC-CEs; if SL-SRB0, SL-SRB1, SL-SRB2, or SL-SRB4 SDUs are included in the transmission to the RX UE, then use the highest priority CAPC; if SL-SRB3 SDUs are included in the transmission to the RX UE, then use the highest priority CAPC for those SL-SRB3 SDUs; and otherwise use the lowest priority, highest priority, or configured CAPC for the logical channel with the sidelink MAC SDUs multiplexed in the transmission to the RX UE.

[0072] In some specific implementations, the CAPC for the transmission is determined based on the mapping between the SL-LCH priority and the CAPC. For example, the mapping can be defined by a mapping table that associates the SL-LCH priority with one of the four CAPCs included in the 3GPP technical standard (and / or other CAPCs). Such mappings can be specified in the 3GPP technical standard and known to the TX UE and the RX UE. In this example, the TX UE can determine the CAPC for transmission to the RX UE based on the following rules: PSFCH, PSCCH, and SL-SSB are associated with the highest priority CAPC; CAPCs for at least one type of MAC-CE are associated with the highest priority CAPC, the lowest priority CAPC, or a CAPC configured by a network node, for example; Padding BSR is associated with the lowest priority CAPC, or depends on its associated logical channel or logical channel group; For other sidelink transmissions, the TX UE determines the SL-LCH priority for transmission, and determines the CAPC for transmission based on the SL-LCH priority and the mapping between the SL-LCH priority and the CAPC.

[0073] In some implementations, the CAPC for the transmission is determined based on a mapping between a layer 1 priority and a CAPC. For example, a mapping may be defined by a mapping table that associates a layer 1 priority with one of the four CAPCs included in the 3GPP technical standard (and / or other CAPCs). Such mapping may be specified in the 3GPP technical standard and known to the TX UE and the RX UE. In this example, the TX UE may determine the CAPC for the transmission to the RX UE based on the following rule: PSFCH, PSCCH, and SL-SSB are associated with the highest priority CAPC; and for other sidelink transmissions, the TX UE (e.g., based on the sidelink control information) determines the layer 1 priority of the transmission, and determines the CAPC for the transmission based on the layer 1 priority and the mapping between the layer 1 priority and the CAPC.

[0074] In some implementations, the TX UE determines the CAPC for transmission to the RX UE based on the following rules: the PSFCH, PSCCH, and SL-SSB are associated with the highest priority CAPC; and for a configured granted transmission, the CAPC for the transmission is determined based on an association between a configured grant configuration index for the transmission and the CAPC (e.g., specified in a mapping table or otherwise).

[0075] In some implementations, the TX UE determines the CAPC for a transmission to the RX UE based on the following rules: PSFCH, PSCCH, and SL-SSB are associated with the highest priority CAPC; and for data transmissions, the CAPC for the transmission is determined based on factors including how long the data has been queued in the buffer and / or how much data is queued in the buffer. In some examples, if the transmission is a retransmission (e.g., an autonomous retransmission after expiration of a configured grant retransmission timer, or a retransmission scheduled by a network node via DCI 3_0), the TX UE can adjust the CAPC to a higher priority CAPC.

[0076] After determining the CAPC for the transmission, the TX UE performs an LBT process (204) on the side link interface (e.g., a channel of the side link interface) based on the determined CAPC. In some examples, performing the LBT process based on the determined CAPC includes adjusting one or more LBT parameters, such as a sensing interval, a contention window size, and / or a channel occupancy time, based on the CAPC. If the LBT fails (e.g., because the channel is not idle), the TX UE may retry the LBT (or time out) as specified in the process. On the other hand, if the LBT succeeds (e.g., because the channel is idle), the TX UE may perform a transmission to the RX UE. In some implementations, the TX UE may include the CAPC in the transmission to the RX UE for use in subsequent processing or transmission. The RX UE may perform process 200 when transmitting to the TX UE in response to the TX UE or otherwise.

[0077] Figure 3 UE 300 according to some embodiments is illustrated. UE 300 may be similar to Figure 1 UE 105 and is essentially interchangeable therewith.

[0078] UE 300 can be any mobile or non-mobile computing device, such as, for example, a mobile phone, a computer, a tablet, an industrial wireless sensor (e.g., microphone, carbon dioxide sensor, pressure sensor, humidity sensor, thermometer, motion sensor, accelerometer, laser scanner, fluid level sensor, inventory sensor, voltage / current meter, actuator, etc.), video monitoring / surveillance equipment (e.g., camera, camcorder, etc.), a wearable device (e.g., a smart watch), a loose IoT device.

[0079] UE 300 may include a processor 302, RF interface circuitry 304, memory / storage 306, a user interface 308, a sensor 310, a driver circuit 312, a power management integrated circuit (PMIC) 314, one or more antennas 316, and a battery 318. The components of UE 300 may be implemented as integrated circuits (ICs), portions of integrated circuits, discrete electronic devices or other modules, logic components, hardware, software, firmware, or a combination thereof. Figure 3 The block diagram of UE 300 is intended to show a high-level view of certain of the components of UE 300. However, some of the components shown may be omitted, additional components may be present, and different arrangements of the components shown may occur in other implementations.

[0080] Components of UE 300 may be coupled to various other components via one or more interconnects 320, which may represent any type of interface, input / output, bus (local, system, or extension), transmission line, trace, optical connection, etc., which allows various circuit components (on a common or different chip or chipset) to interact with each other.

[0081] The processor 302 may include processor circuits such as, for example, a baseband processor circuit (BB) 322A, a central processor unit circuit (CPU) 322B, and a graphics processor unit circuit (GPU) 322C. The processor 302 may include any type of circuit or processor circuit that executes or otherwise operates computer-executable instructions (such as program codes, software modules, or functional processes from the memory / storage device 306) to cause the UE 300 to perform operations as described herein.

[0082] In some implementations, the processor 302 is configured to perform operations that cause the UE to determine a CAPC for transmission to a second UE via a sidelink channel. In addition, the processor 302 is configured to perform operations that cause the UE to perform a listen-before-talk procedure based on the determined CAPC for transmission.

[0083] In some embodiments, the baseband processor circuit 322A can access the communication protocol stack 324 in the memory / storage device 306 to communicate through a 3GPP compatible network. Generally speaking, the baseband processor circuit 322A can access the communication protocol stack to: perform user plane functions at the PHY layer, MAC layer, RLC layer, PDCP layer, SDAP layer, and PDU layer; and perform control plane functions at the PHY layer, MAC layer, RLC layer, PDCP layer, RRC layer, and non-access layer. In some embodiments, the PHY layer operations may be additionally / alternatively performed by components of the RF interface circuit 304. The baseband processor circuit 322A may generate or process a baseband signal or waveform that carries information in a 3GPP compatible network. In some embodiments, the waveform for NR may be based on cyclic prefix OFDM ("CP-OFDM") in the uplink or downlink, and discrete Fourier transform spread OFDM ("DFT-S-OFDM") in the uplink.

[0084] The memory / storage 306 may include one or more non-transitory computer-readable media including instructions (e.g., the communication protocol stack 324) that may be executed by one or more processors in the processor 302 to enable the UE 300 to perform various operations described herein. The memory / storage 306 includes any type of volatile memory or non-volatile memory that may be distributed throughout the UE 300. In some embodiments, some of the memory / storage 306 may be located on the processor 302 itself (e.g., L1 cache and L2 cache), while other memory / storage 306 is located outside the processor 302 but can be accessed via a memory interface. The memory / storage 306 may include any suitable volatile memory or non-volatile memory, such as, but not limited to, dynamic random access memory (DRAM), static random access memory (SRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state memory, or any other type of memory device technology.

[0085] The RF interface circuit 304 may include a transceiver circuit and a radio frequency front end module (RFEM) that allows the UE 300 to communicate with other devices through a radio access network. The RF interface circuit 304 may include various elements arranged in a transmit path or a receive path. These elements may include, for example, switches, mixers, amplifiers, filters, synthesizer circuits, control circuits, etc.

[0086] In the receive path, the RFEM may receive the radiated signal from the air interface via one or more antennas 316 and proceed to filter and amplify the signal (using a low noise amplifier). The signal may be provided to a transceiver's receiver, which down-converts the RF signal to a baseband signal provided to a baseband processor of the processor 302.

[0087] In the transmit path, the transmitter of the transceiver up-converts the baseband signal received from the baseband processor and provides the RF signal to the RFEM. The RFEM may amplify the RF signal through a power amplifier before the signal is radiated across the air interface via one or more antennas 316. In various embodiments, the RF interface circuit 304 may be configured to transmit / receive signals in a manner compatible with NR access technology.

[0088] One or more antennas 316 may include antenna elements to convert electrical signals into radio waves to travel through the air and convert received radio waves into electrical signals. These antenna elements may be arranged into one or more antenna panels. One or more antennas 316 may have antenna panels that are omnidirectional, directional, or a combination thereof to achieve beamforming and multiple input / multiple output communications. One or more antennas 316 may include microstrip antennas, printed antennas manufactured on the surface of one or more printed circuit boards, patch antennas, phased array antennas, etc. One or more antennas 316 may have one or more panels that are designed for specific frequency bands including bands in FRI or FR2.

[0089] The user interface 308 includes various input / output (I / O) devices designed to enable a user to interact with the UE 300. The user interface 308 includes input device circuits and output device circuits. The input device circuit includes any physical or virtual components for accepting input, and in particular includes one or more physical or virtual buttons (e.g., a reset button), a physical keyboard, a keypad, a mouse, a touch pad, a touch screen, a microphone, a scanner, or a headset, etc. The output device circuit includes any physical or virtual components for displaying information or otherwise delivering information (such as sensor readings, actuator positions, or other similar information). The output device circuit may include any number or combination of audio or visual displays, in particular including one or more simple visual outputs / indicators (e.g., binary state indicators (such as light emitting diodes "LEDs") and multi-character visual outputs) or more complex outputs (such as display devices or touch screens (e.g., liquid crystal displays "LCDs", LED displays, quantum dot displays, projectors, etc.)), where the output of characters, graphics, multimedia objects, etc. is generated or produced by the operation of the UE 300.

[0090] Sensor 310 may include a device, module, or subsystem that is designed to detect events or changes in its environment and to communicate information about the detected events (sensor data) to some other device, module, subsystem, etc. Examples of such sensors include, among others: an inertial measurement unit including an accelerometer, gyroscope, or magnetometer; a microelectromechanical system or nanoelectromechanical system including a three-axis accelerometer, three-axis gyroscope, or magnetometer; a level sensor; a flow sensor; a temperature sensor (e.g., a thermistor); a pressure sensor; a barometric pressure sensor; a gravity meter; an altimeter; an image capture device (e.g., a camera or a lensless aperture); a light detection and ranging sensor; a proximity sensor (e.g., an infrared radiation detector, etc.); a depth sensor; an ambient light sensor; an ultrasonic transceiver; a microphone or other similar audio capture device; and the like.

[0091] The driver circuit 312 may include software and hardware elements that operate to control specific devices embedded in, attached to, or otherwise communicatively coupled to the UE 300. The driver circuit 312 may include various drivers to allow other components to interact with or control various input / output (I / O) devices that may be present in or connected to the UE 300. For example, the driver circuit 312 may include: a display driver for controlling and allowing access to a display device, a touch screen driver for controlling and allowing access to a touch screen interface, a sensor driver for obtaining sensor readings of the sensor 310 and controlling and allowing access to the sensor 310, a driver for obtaining an actuator position of an electromechanical component or controlling and allowing access to an electromechanical component, a camera driver for controlling and allowing access to an embedded image capture device, and an audio driver for controlling and allowing access to one or more audio devices.

[0092] The PMIC 314 may manage the power provided to various components of the UE 300. Specifically, with respect to the processor 302, the PMIC 314 may control power source selection, voltage scaling, battery charging, or DC-DC conversion.

[0093] In some embodiments, the PMIC 314 may control or otherwise be part of various power saving mechanisms of the UE 300, including DRX, as discussed herein. The battery 318 may power the UE 300, but in some examples, the UE 300 may be mounted in a fixed location and may have a power source coupled to the grid. The battery 318 may be a lithium-ion battery, a metal-air battery (such as a zinc-air battery, an aluminum-air battery, a lithium-air battery, etc.). In some specific implementations, such as in vehicle-based applications, the battery 318 may be a typical lead-acid automotive battery.

[0094] Figure 4An access node 400 (e.g., a base station or gNB) according to some embodiments is illustrated. Access node 400 may be similar to base station 110 and may be substantially interchangeable with the base station. Access node 400 may include a processor 402, RF interface circuitry 404, core network (CN) interface circuitry 406, memory / storage circuitry 408, and one or more antennas 410.

[0095] The components of access node 400 may be coupled to various other components via one or more interconnects 412. Processor 402, RF interface circuitry 404, memory / storage circuitry 408 (including communication protocol stack 414), one or more antennas 410, and interconnects 412 may be similar to those described with reference to FIG. Figure 3 Like-named elements are shown and described.For example, processor 402 may include processor circuits such as, for example, baseband processor circuit (BB) 416A, central processor unit circuit (CPU) 416B, and graphics processor unit circuit (GPU) 416C.

[0096] The CN interface circuit 406 may provide a connection to a core network (e.g., a 5GC using a fifth generation core network (5GC) compatible network interface protocol such as a carrier Ethernet protocol or some other suitable protocol). The network connection may be provided to / from the access node 400 via optical fiber or wireless backhaul. The CN interface circuit 406 may include one or more dedicated processors or FPGAs for communicating using one or more of the aforementioned protocols. In some implementations, the CN interface circuit 406 may include multiple controllers for providing connections to other networks using the same or different protocols.

[0097] As used herein, the terms "access node", "access point", etc. may be described as equipment that provides radio baseband functionality for data and / or voice connections between a network and one or more users. These access nodes may be referred to as BS, gNB, RAN node, eNB, NodeB, RSU, TRxP or TRP, etc., and may include ground stations (e.g., terrestrial access points) or satellite stations that provide coverage within a geographic area (e.g., a cell). As used herein, the terms "NG RAN node", etc. may refer to an access node 400 (e.g., a gNB) operating in an NR or 5G system, and the terms "E-UTRAN node", etc. may refer to an access node 400 (e.g., an eNB) operating in an LTE or 4G system. According to various embodiments, the access node 400 may be implemented as one or more of a dedicated physical device such as a macrocell base station and / or a low power (LP) base station for providing a femtocell, picocell or other similar cell with a smaller coverage area, smaller user capacity or higher bandwidth than a macrocell.

[0098] In some embodiments, all or part of the access node 400 may be implemented as one or more software entities running on a server computer as part of a virtual network that may be referred to as a CRAN and / or a virtual baseband unit pool (vBBUP). In these embodiments, the CRAN or vBBUP may implement a RAN functional split, such as a PDCP split, where the RRC and PDCP layers are operated by the CRAN / vBBUP and other L2 protocol entities are operated by the access node 400; a MAC / PHY split, where the RRC, PDCP, RLC, and MAC layers are operated by the CRAN / vBBUP and the PHY layer is operated by the access node 400; or a "lower PHY" split, where the RRC, PDCP, RLC, MAC layers, and upper portions of the PHY layers are operated by the CRAN / vBBUP and the lower portions of the PHY layers are operated by the access node 400.

[0099] In the V2X scenario, the access node 400 may be an RSU or act as an RSU. The term "road side unit" or "RSU" may refer to any traffic infrastructure entity used for V2X communication. The RSU may be implemented in or by a suitable RAN node or a stationed (or relatively stationed) UE, wherein an RSU implemented in or by a UE may be referred to as a "UE-type RSU", an RSU implemented in or by an eNB may be referred to as an "eNB-type RSU", an RSU implemented in or by a gNB may be referred to as a "gNB-type RSU", and so on.

[0100] For ease of description, various components may be described as performing one or more tasks. Such descriptions should be interpreted as including the phrase "configured to". Representing a component configured to perform one or more tasks expressly intends that the component does not invoke the interpretation of 35 U.S.C. §112(f).

[0101] For one or more embodiments, at least one of the components shown in one or more of the foregoing figures may be configured to perform one or more operations, techniques, processes, or methods described in the following example section. For example, the baseband circuit described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples described below. For another example, the circuits associated with the UE, base station, network element, etc. described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples described below in the example section.

[0102] Example

[0103] Embodiment 1 includes one or more processors of a first user equipment (UE), wherein the one or more processors are configured to cause the first UE to perform operations, the operations comprising: determining, by the first UE, a channel access priority category (CAPC) for transmission to a second UE via a side link interface; and performing a listen-before-talk process on the side link interface based on the determined CAPC.

[0104] Embodiment 2 is one or more processors according to embodiment 1, wherein determining the CAPC for the transmission includes: determining a PC5 5QI (PQI) for the transmission to the second UE through the side link interface; and determining the CAPC for the transmission based on the PQI for the transmission and a mapping between the PQI and the CAPC.

[0105] Embodiment 3 is one or more processors of embodiment 1 or 2, wherein the PQI for the transmission is determined based on a quality of service (QoS) associated with the transmission.

[0106] Embodiment 4 is one or more processors according to any one of embodiments 1 to 3, wherein the transmission is associated with a non-standardized quality of service (QoS), and wherein determining the PQI for the transmission includes: determining a standardized QoS based on the non-standardized QoS; and using the PQI associated with the standardized QoS as the PQI for the transmission.

[0107] Embodiment 5 is one or more processors according to any one of embodiments 1 to 4, wherein determining the CAPC used for the transmission includes: determining a sidelink logical channel used for the transmission to the second UE through the sidelink interface; and determining the CAPC used for the transmission based on the sidelink logical channel used for the transmission and a mapping between the sidelink logical channel and the CAPC.

[0108] Embodiment 6 is one or more processors according to any one of embodiments 1 to 5, wherein the mapping associates a physical sidelink feedback channel (PSFCH) or a physical sidelink control channel (PSCCH) with a highest priority CAPC.

[0109] Embodiment 7 is one or more processors according to any one of embodiments 1 to 6, wherein determining the CAPC used for the transmission includes: determining the type of data included in the transmission to the second UE through the side link interface; and determining the CAPC used for the transmission based on the type of data included in the transmission and the mapping between the type of data transmission and the CAPC.

[0110] Embodiment 8 is one or more processors according to any one of embodiments 1 to 7, wherein the mapping associates a side link synchronization signal block (SL-SSB) with a highest priority CAPC.

[0111] Embodiment 9 is one or more processors according to any one of embodiments 1 to 8, wherein the mapping associates at least one type of medium access control (MAC) control element (CE) with a highest priority CAPC or a lowest priority CAPC.

[0112] Embodiment 10 is one or more processors according to any one of embodiments 1 to 9, wherein the mapping associates a fill buffer status report (BFR) with a lowest priority CAPC.

[0113] Embodiment 11 is one or more processors according to any one of embodiments 1 to 10, wherein determining the CAPC for the transmission includes: determining a bearer for the transmission to the second UE through the sidelink interface; and determining the CAPC for the transmission based on the bearer for the transmission and a mapping between the bearer and the CAPC.

[0114] Embodiment 12 is one or more processors according to any one of embodiments 1 to 11, wherein the mapping associates a sidelink signaling radio bearer 0 (SL-SRB0), SL-SRB1, or SL-SRB4 with a highest priority CAPC.

[0115] Embodiment 13 is one or more processors according to any one of embodiments 1 to 12, wherein the mapping associates a sidelink signaling radio bearer 2 (SL-SRB2) with a highest priority CAPC or a configured CAPC.

[0116] Embodiment 14 is one or more processors according to any one of embodiments 1 to 13, wherein the bearer used for the transmission is a sidelink signaling radio bearer 2 (SL-SRB2), SL-SRB3, or a sidelink data radio bearer (SL-DRB), and wherein the operation also includes receiving an indication of the CAPC used for the transmission from an access node.

[0117] Embodiment 15 is one or more processors according to any one of embodiments 1 to 14, wherein the bearer used for the transmission is a sidelink signaling radio bearer 2 (SL-SRB2), SL-SRB3, or a sidelink data radio bearer (SL-DRB), and wherein when the transmission includes one or more medium access control (MAC) control elements (CEs), the highest priority CAPC among the one or more MAC CEs is used as the CAPC for the transmission.

[0118] Embodiment 16 is one or more processors according to any one of embodiments 1 to 15, wherein the bearer used for the transmission is a sidelink signaling radio bearer 2 (SL-SRB2), SL-SRB3, or a sidelink data radio bearer (SL-DRB), and wherein when the transmission includes one or more of an SRB0 service data unit (SDU), an SRB1 SDU, an SRB2 SDU, or an SRB4 SDU, a highest priority CAPC is used as the CAPC for the transmission.

[0119] Embodiment 17 is one or more processors according to any one of embodiments 1 to 16, wherein the bearer used for the transmission is a sidelink signaling radio bearer 2 (SL-SRB2), SL-SRB3, or a sidelink data radio bearer (SL-DRB), and wherein when the transmission includes one or more SL-SRB3 service data units (SDUs), the highest priority CAPC among the one or more SL-SRB3 SDUs is used as the CAPC for the transmission.

[0120] Embodiment 18 is one or more processors according to any one of embodiments 1 to 17, wherein determining the CAPC for the transmission includes: determining a logical channel priority for the transmission; and determining the CAPC for the transmission based on the logical channel priority for the transmission and a mapping between a sidelink logical channel (SL-LCH) priority and CAPC.

[0121] Embodiment 19 is one or more processors according to any one of embodiments 1 to 18, wherein determining the CAPC for the transmission includes: determining a layer 1 priority for the transmission; and determining the CAPC for the transmission based on the layer 1 priority for the transmission and a mapping between the layer 1 priority and the CAPC.

[0122] Embodiment 20 is one or more processors according to any one of embodiments 1 to 19, wherein the transmission is a configured authorized transmission, and wherein the CAPC for the transmission is determined based on a configured authorized configuration index.

[0123] Embodiment 21 is one or more processors according to any one of embodiments 1 to 20, wherein the CAPC for the transmission is determined based at least in part on how long data for the transmission has been queued in a buffer or how much data is queued in the buffer.

[0124] Embodiment 22 is one or more processors according to any one of embodiments 1 to 21, the operations further comprising adjusting the CAPC used for the transmission to a higher priority CAPC when the transmission includes a retransmission.

[0125] Embodiment 23 is one or more processors according to any one of embodiments 1 to 22, the operation also including sending the transmission to the second UE through the sidelink interface after performing the listen-before-talk procedure based on the determined CAPC.

[0126] Embodiment 24 is one or more processors according to any one of embodiments 1 to 23, wherein the sending includes an indication of the determined CAPC.

[0127] Embodiment 25 is one or more processors according to any one of embodiments 1 to 24, and the operations also include receiving an indication of the CAPC used for the transmission from the second UE.

[0128] Embodiment 26 is one or more processors according to any one of embodiments 1 to 25, wherein performing the listen-before-talk process based on the determined CAPC includes adjusting one or more listen-before-talk parameters based on the determined CAPC.

[0129] Embodiment 27 includes a non-transitory computer storage medium encoded with instructions executable by one or more processors to cause the one or more processors to perform operations according to any one of Embodiments 1-26.

[0130] Embodiment 28 includes a device comprising: one or more processors, and a memory storing instructions, the instructions being executable by the one or more processors to cause the one or more processors to perform operations according to any one of Embodiments 1 to 26.

[0131] Embodiment 29 includes a device comprising: one or more processors, and a memory storing instructions, the instructions being executable by the one or more processors to cause the one or more processors to perform operations according to any one of embodiments 1 to 26.

[0132] Embodiment 30 includes a method for performing the operations according to any one of Embodiments 1 to 26.

[0133] Embodiment 31 includes a user equipment (UE), wherein the user equipment (UE) includes: one or more processors, and a memory, wherein the memory stores instructions, and the instructions are executable by the one or more processors to enable the one or more processors to perform operations according to any one of embodiments 1 to 26.

[0134] Embodiment 32 includes a system comprising: one or more processors, and a memory storing instructions, wherein the instructions are executable by the one or more processors to cause the one or more processors to perform operations according to any one of embodiments 1 to 26.

[0135] Embodiment 33 may include a device comprising logic components, modules, or circuits for performing one or more elements of operations described or associated with any of Embodiments 1 to 26, or any other operations or processes described herein.

[0136] Embodiment 34 may include a method, technique or process described or associated with the operation of any one of Embodiments 1 to 26, or a portion or component thereof.

[0137] Embodiment 35 may include a device, such as user equipment, comprising: one or more processors and one or more computer-readable media, wherein the one or more computer-readable media include instructions that, when executed by the one or more processors, cause the one or more processors to perform a method, technique, process, or portion thereof described in or related to an operation according to any one of embodiments 1 to 26.

[0138] Embodiment 36 may include a computer program including instructions, wherein execution of the program by a processing element causes the processing element to perform a method, technique, or process, or a portion thereof, described in or related to the operation according to any one of Embodiments 1 to 26. The operations or actions performed by the instructions executed by the processing element may include the operations according to any one of Embodiments 1 to 26.

[0139] Embodiment 37 may include a method of communicating in a wireless network as shown and described herein.

[0140] Embodiment 38 may include a system for providing wireless communication as shown and described herein. The operations or actions performed by the system may include operations according to any one of Embodiments 1-26.

[0141] Embodiment 39 may include an apparatus for providing wireless communication as shown and described herein. The operations or actions performed by the apparatus may include operations according to any one of Embodiments 1 to 26.

[0142] The previously described operations of Examples 1 to 26 can be implemented using a computer-implemented method; a non-transitory computer-readable medium storing computer-readable instructions to perform the computer-implemented method; and a computer system comprising a computer memory interoperably coupled to a hardware processor configured to execute the computer-implemented method or instructions stored on the non-transitory computer-readable medium.

[0143] Unless explicitly stated otherwise, any of the above embodiments may be combined with any other embodiment (or combination of embodiments). The foregoing description of one or more specific implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of the specific implementations to the precise form disclosed. Modifications and variations are possible in view of the above teachings or may be obtained from the practice of various specific implementations.

[0144] Although the above specific implementations have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to include all such variations and modifications.

[0145] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

Claims

1. One or more processors of a first user equipment (UE), the one or more processors configured to cause the first UE to perform operations, the operations comprising: determining, by the first UE, a channel access priority class (CAPC) for transmission to a second UE via a sidelink interface; as well as A listen-before-talk procedure is performed on the sidelink interface based on the determined CAPC.

2. The one or more processors of claim 1 , wherein determining the CAPC for the transmission comprises: determining a PC55QI (PQI) for the transmission to the second UE over the sidelink interface; as well as The CAPC for the transmission is determined based on the PQI for the transmission and a mapping between the PQI and the CAPC.

3. The one or more processors of claim 2, wherein the PQI for the transmission is determined based on a quality of service (QoS) associated with the transmission.

4. The one or more processors of claim 2, wherein the transmission is associated with a non-standardized quality of service (QoS), and wherein determining the PQI for the transmission comprises: Determining a standardized QoS based on the non-standardized QoS; as well as A PQI associated with the standardized QoS is used as the PQI for the transmission.

5. The one or more processors of claim 1 , wherein determining the CAPC for the transmission comprises: determining a sidelink logical channel for the transmission to the second UE through the sidelink interface; as well as The CAPC for the transmission is determined based on the sidelink logical channel used for the transmission and a mapping between sidelink logical channels and CAPCs.

6. The one or more processors of claim 5, wherein the mapping associates a physical sidelink feedback channel (PSFCH) or a physical sidelink control channel (PSCCH) with a highest priority CAPC.

7. The one or more processors of claim 1 , wherein determining the CAPC for the transmission comprises: determining a type of data included in the transmission to the second UE over the sidelink interface; as well as The CAPC for the transmission is determined based on the type of data included in the transmission and a mapping between types of data transmissions and CAPCs.

8. The one or more processors of claim 7, wherein the mapping associates a side link synchronization signal block (SL-SSB) with a highest priority CAPC.

9. The one or more processors of claim 7, wherein the mapping associates at least one type of medium access control (MAC) control element (CE) with a highest priority CAPC or a lowest priority CAPC.

10. The one or more processors of claim 7, wherein the mapping associates a fill buffer status report (BFR) with a lowest priority CAPC.

11. The one or more processors of claim 1 , wherein determining the CAPC for the transmission comprises: determining a bearer for the transmission to the second UE through the sidelink interface; as well as The CAPC for the transmission is determined based on the bearer for the transmission and a mapping between bearers and CAPCs.

12. The one or more processors of claim 11, wherein the mapping associates a sidelink signaling radio bearer 0 (SL-SRB0), SL-SRB1, or SL-SRB4 with a highest priority CAPC.

13. The one or more processors of claim 11, wherein the mapping associates a sidelink signaling radio bearer 2 (SL-SRB2) with a highest priority CAPC or a configured CAPC.

14. The one or more processors of claim 1 , wherein the bearer used for the transmission is a sidelink signaling radio bearer 2 (SL-SRB2), SL-SRB3, or a sidelink data radio bearer (SL-DRB), and wherein the operations further comprise receiving an indication of the CAPC used for the transmission from an access node.

15. The one or more processors of claim 1 , wherein the bearer used for the transmission is a sidelink signaling radio bearer 2 (SL-SRB2), SL-SRB3, or a sidelink data radio bearer (SL-DRB), and wherein when the transmission includes one or more medium access control (MAC) control elements (CEs), a highest priority CAPC among the one or more MAC CEs is used as the CAPC for the transmission.

16. The one or more processors of claim 1, wherein the bearer used for the transmission is a sidelink signaling radio bearer 2 (SL-SRB2), SL-SRB3, or a sidelink data radio bearer (SL-DRB), and wherein when the transmission includes one or more of an SRB0 service data unit (SDU), an SRB1 SDU, an SRB2 SDU, or an SRB4 SDU, a highest priority CAPC is used as the CAPC for the transmission.

17. The one or more processors of claim 1, wherein the bearer used for the transmission is a sidelink signaling radio bearer 2 (SL-SRB2), a SL-SRB3, or a sidelink data radio bearer (SL-DRB), and wherein when the transmission includes one or more SL-SRB3 service data units (SDUs), a highest priority CAPC among the one or more SL-SRB3 SDUs is used as the CAPC for the transmission.

18. The one or more processors of claim 1 , wherein determining the CAPC for the transmission comprises: determining a logical channel priority for said sending; as well as The CAPC for the transmission is determined based on the logical channel priority for the transmission and a mapping between a sidelink logical channel (SL-LCH) priority and CAPC.

19. The one or more processors of claim 1 , wherein determining the CAPC for the transmission comprises: determining a layer 1 priority for the sending; as well as The CAPC for the transmission is determined based on the layer 1 priority for the transmission and a mapping between layer 1 priority and CAPC.

20. The one or more processors of claim 1, wherein the transmission is a configured authorized transmission, and wherein the CAPC for the transmission is determined based on a configured authorized configuration index.

21. The one or more processors of claim 1, wherein the CAPC for the transmission is determined based at least in part on how long data for the transmission has been queued in a buffer or how much data is queued in the buffer.

22. The one or more processors of claim 1, the operations further comprising adjusting the CAPC used for the transmission to a higher priority CAPC when the transmission comprises a retransmission.

23. The one or more processors of claim 1, the operations further comprising sending the transmission to the second UE over the sidelink interface after performing the listen-before-talk procedure based on the determined CAPC.

24. The one or more processors of claim 23, wherein the transmitting comprises an indication of the determined CAPC.

25. The one or more processors of claim 1, the operations further comprising receiving, from the second UE, an indication of the CAPC to use for the transmission.

26. The one or more processors of claim 1, wherein performing the listen-before-talk process based on the determined CAPC comprises adjusting one or more listen-before-talk parameters based on the determined CAPC.

27. A non-transitory computer storage medium encoded with instructions that, when executed by at least one processor, cause the at least one processor to perform the operations of any one of claims 1 to 26.

28. A system comprising at least one processor and at least one storage device storing instructions, the instructions being executable by the at least one processor to cause the at least one processor to perform the operations of any one of claims 1 to 26.

29. An apparatus comprising at least one processor and at least one storage device storing instructions, the instructions being executable by the at least one processor to cause the at least one processor to perform the operations of any one of claims 1 to 26.

30. A method for performing the operations according to any one of claims 1 to 26.

Images