Terminal and communication method

Abstract

This terminal comprises: a control unit that determines a channel access priority class (CAPC) to be applied to sidelink transmission including a physical sidelink feedback channel (PSFCH) and a sidelink synchronization signal / physical sidelink broadcast channel block (S-SSB) in an unlicensed band, and executes a channel access procedure for executing the sidelink transmission; and a transmission unit that executes the sidelink transmission if the channel access procedure is successful.

Description

Terminal and communication method

[0001] The present invention relates to a terminal and a communication method in a wireless communication system.

[0002] In LTE (Long Term Evolution) and successor systems to LTE (for example, LTE-A (LTE Advanced) and NR (New Radio) (also referred to as 5G)), D2D (Device to Device) technology is being considered, in which terminals communicate directly with each other without going through a base station (for example, Non-Patent Document 1).

[0003] D2D reduces traffic between terminals and base stations and enables communication between terminals even when the base station becomes unable to communicate due to a disaster or the like. In addition, although 3GPP (registered trademark) refers to D2D as "sidelink," the more general term "D2D" is used in this specification. However, in the description of the embodiments described later, sidelink is also used as necessary.

[0004] D2D communication is broadly divided into D2D discovery (also referred to as D2D discovery) for discovering other terminals with which communication is possible, and D2D communication (also referred to as D2D direct communication, D2D communication, terminal-to-terminal direct communication, etc.) for direct communication between terminals. Hereinafter, when there is no particular distinction between D2D communication, D2D discovery, etc., they are simply referred to as D2D. Furthermore, signals transmitted and received in D2D are referred to as D2D signals. Various use cases for services related to Vehicle to Everything (V2X) in NR have been studied (for example, Non-Patent Document 2).

[0005] Furthermore, in NR Release 17 (e.g., Non-Patent Document 3), the use of a higher frequency band than in previous releases is being considered. For example, in the frequency band from 52.6 GHz to 71 GHz, applicable numerology including subcarrier spacing, channel bandwidth, etc., physical layer design, and expected interference in actual wireless communication are being considered.

[0006] 3GPP TS 38.300 V18.0.0 (2023-12)3GPP TR 22.886 V16.2.0 (2018-12)3GPP TS 38.306 V18.0.0 (2023-12)3GPP TS 37.213 V18.1.0 (2023-12)

[0007] Newly operated frequency bands using higher frequencies than conventional ones are defined as unlicensed bands. Various regulations are defined in unlicensed bands, and for example, LBT (Listen Before Talk) is implemented when accessing a channel. When D2D communication is performed in these high frequency bands, operations that comply with the regulations in the unlicensed bands are required.

[0008] When performing Type 1 LBT in sidelink communication in an unlicensed band, the time period for performing LBT is determined based on CAPC (Channel access priority class). However, there are cases where the method for determining CAPC is not specified.

[0009] The present invention has been made in consideration of the above points, and aims to determine a channel access priority class (CAPC) to be applied to LBT (Listen before talk) in an unlicensed band.

[0010] According to the disclosed technique, there is provided a terminal including: a control unit that determines a channel access priority class (CAPC) to be applied to sidelink transmission including a physical sidelink feedback channel (PSFCH) and a sidelink synchronization signal / physical sidelink broadcast channel block (S-SSB) in an unlicensed band, and that performs a channel access procedure for performing the sidelink transmission; and a transmission unit that performs the sidelink transmission if the channel access procedure is successful.

[0011] According to the disclosed technology, it is possible to determine the channel access priority class (CAPC) to be applied to LBT (Listen before talk) in an unlicensed band.

[0012] 1 is a diagram for explaining V2X. FIG. 1 is a sequence diagram showing an operation example (1) of V2X. FIG. 2 is a sequence diagram showing an operation example (2) of V2X. FIG. 3 is a sequence diagram showing an operation example (3) of V2X. FIG. 4 is a sequence diagram showing an operation example (4) of V2X. FIG. 5 is a diagram showing an example of sensing operation. FIG. 6 is a flowchart for explaining an example of preemption operation. FIG. 7 is a diagram showing an example of preemption operation. FIG. 8 is a diagram showing an example of partial sensing operation. FIG. 9 is a diagram for explaining an example of periodic partial sensing. FIG. 10 is a diagram for explaining an example of continuous partial sensing. FIG. 11 is a diagram showing an example of frequency ranges in an embodiment of the present invention. FIG. 12 is a diagram for explaining an LBT example (1). FIG. 13 is a diagram for explaining an LBT example (2). FIG. 14 is a diagram for explaining an LBT example (3). FIG. 14 is a diagram for explaining a wideband operation example (1). FIG. 15 is a diagram for explaining a wideband operation example (2). FIG. 16 is a diagram for explaining a wideband operation example (3). FIG. 17 is a diagram for explaining a wideband operation example (4). FIG. 18 is a flowchart for explaining a transmission example in an embodiment of the present invention. FIG. 19 is a diagram showing an example of a functional configuration of a base station 10 in an embodiment of the present invention. 1 is a diagram showing an example of the functional configuration of a terminal 20 according to an embodiment of the present invention; FIG. 2 is a diagram showing an example of the hardware configuration of a base station 10 or a terminal 20 according to an embodiment of the present invention; FIG. 3 is a diagram showing an example of the configuration of a vehicle 2001 according to an embodiment of the present invention;

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the embodiment described below is an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0014] In the operation of the wireless communication system according to the embodiment of the present invention, existing technology is used as appropriate. However, the existing technology is, for example, the existing LTE, but is not limited to the existing LTE. Furthermore, the term "LTE" used in this specification has a broad meaning including LTE-Advanced, and systems subsequent to LTE-Advanced (e.g., NR), or wireless LAN (Local Area Network), unless otherwise specified.

[0015] Furthermore, in the embodiment of the present invention, the duplex method may be a time division duplex (TDD) method, a frequency division duplex (FDD) method, or another method (for example, flexible duplex, etc.).

[0016] Furthermore, in the embodiments of the present invention, "configuring" radio parameters etc. may mean that predetermined values ​​are pre-configured, or that radio parameters notified from the base station 10 or the terminal 20 are set.

[0017] FIG. 1 is a diagram for explaining V2X. 3GPP is studying the realization of V2X (Vehicle to Everything) or eV2X (enhanced V2X) by extending the D2D function, and is currently working on specifications. As shown in FIG. 1 , V2X is a part of ITS (Intelligent Transport Systems) and is a collective term for V2V (Vehicle to Vehicle), which refers to a communication mode between vehicles; V2I (Vehicle to Infrastructure), which refers to a communication mode between a vehicle and a roadside unit (RSU: Road-Side Unit) installed on the side of the road; V2N (Vehicle to Network), which refers to a communication mode between a vehicle and an ITS server; and V2P (Vehicle to Pedestrian), which refers to a communication mode between a vehicle and a mobile terminal carried by a pedestrian.

[0018] In addition, 3GPP is studying V2X using LTE or NR cellular communication and terminal-to-terminal communication. V2X using cellular communication is also called cellular V2X. NR V2X is being studied to achieve high capacity, low latency, high reliability, and quality of service (QoS) control.

[0019] It is expected that future studies will be conducted on LTE or NR V2X that are not limited to 3GPP specifications. For example, it is expected that studies will be conducted on ensuring interoperability, reducing costs by implementing higher layers, methods for using or switching between multiple RATs (Radio Access Technologies), compliance with regulations in each country, and methods for acquiring, distributing, managing databases, and using data from LTE or NR V2X platforms.

[0020] In the embodiments of the present invention, a communication device is mainly assumed to be mounted on a vehicle, but the embodiments of the present invention are not limited to this. For example, the communication device may be a terminal held by a person, a device mounted on a drone or an aircraft, a base station, an RSU, a relay station (relay node), a terminal with scheduling capability, etc.

[0021] Note that SL (Sidelink) may be distinguished from UL (Uplink) or DL ​​(Downlink) based on any one or a combination of the following 1) to 4). SL may also be called by other names: 1) Resource allocation in the time domain 2) Resource allocation in the frequency domain 3) Synchronization signal to be referenced (including SLSS (Sidelink Synchronization Signal)) 4) Reference signal used in path loss measurement for transmission power control

[0022] Furthermore, with respect to SL or UL OFDM (Orthogonal Frequency Division Multiplexing), CP-OFDM (Cyclic-Prefix OFDM), DFT-S-OFDM (Discrete Fourier Transform - Spread - OFDM), OFDM without transform precoding, or OFDM with transform precoding may be applied.

[0023] In the LTE SL, Mode 3 and Mode 4 are defined for SL resource allocation to the terminal 20. In Mode 3, transmission resources are dynamically allocated by DCI (Downlink Control Information) transmitted from the base station 10 to the terminal 20. Also, in Mode 3, SPS (Semi Persistent Scheduling) is possible. In Mode 4, the terminal 20 autonomously selects transmission resources from a resource pool.

[0024] In addition, the term "slot" in the embodiments of the present invention may be interpreted as a symbol, a minislot, a subframe, a radio frame, or a TTI (Transmission Time Interval). In addition, the term "cell" in the embodiments of the present invention may be interpreted as a cell group, a carrier component, a BWP, a resource pool, a resource, a RAT (Radio Access Technology), a system (including a wireless LAN), or the like.

[0025] In the embodiment of the present invention, the terminal 20 is not limited to a V2X terminal, and may be any type of terminal that performs D2D communication. For example, the terminal 20 may be a terminal carried by a user, such as a smartphone, or may be an IoT (Internet of Things) device, such as a smart meter.

[0026] In addition, it is assumed that NR-SL supports hybrid automatic repeat request (HARQ) for sidelink unicast and groupcast. Furthermore, in NR-V2X, sidelink feedback control information (SFCI) including a HARQ response is defined. Furthermore, it is being considered that SFCI will be transmitted via a physical sidelink feedback channel (PSFCH).

[0027] In the following description, the PSFCH is used for transmitting the HARQ-ACK on the sidelink, but this is just an example. For example, the HARQ-ACK may be transmitted on the sidelink using the PSCCH (Physical Sidelink Control Channel), the PSSCH (Physical Sidelink Shared Channel), or another channel.

[0028] Hereinafter, for convenience, information reported by the terminal 20 in HARQ will generally be referred to as HARQ-ACK. This HARQ-ACK may also be referred to as HARQ-ACK information. More specifically, a codebook applied to HARQ-ACK information reported from the terminal 20 to the base station 10 or the like will be referred to as a HARQ-ACK codebook. The HARQ-ACK codebook defines the bit string of the HARQ-ACK information. Note that in addition to ACK (positive response), NACK (negative response) is also transmitted by "HARQ-ACK".

[0029] Fig. 2 is a sequence diagram showing an operation example (1) of V2X. As shown in Fig. 2, the wireless communication system according to the embodiment of the present invention may include a terminal 20A and a terminal 20B. Note that, although a large number of user devices actually exist, Fig. 2 shows the terminal 20A and the terminal 20B as an example.

[0030] Hereinafter, when there is no particular distinction between the terminals 20A, 20B, etc., they will be simply referred to as "terminal 20" or "user equipment." While Fig. 2 shows an example in which the terminals 20A and 20B are both within the coverage of a cell, the operation in the embodiment of the present invention can also be applied to a case in which the terminal 20B is outside the coverage.

[0031] As described above, in this embodiment, the terminal 20 is, for example, a device mounted on a vehicle such as an automobile, and has a cellular communication function as a UE in LTE or NR, and a side link function. The terminal 20 may be a general mobile terminal (such as a smartphone). The terminal 20 may also be an RSU. The RSU may be a UE type RSU having the function of a UE, or a gNB type RSU having the function of a base station device.

[0032] It should be noted that the terminal 20 does not have to be a device in a single housing; for example, even if various sensors are distributed throughout the vehicle, the terminal 20 may be a device including the various sensors.

[0033] Furthermore, the processing of sidelink transmission data by the terminal 20 is basically the same as the processing of UL transmission in LTE or NR. For example, the terminal 20 scrambles and modulates codewords of the transmission data to generate complex-valued symbols, maps the complex-valued symbols (transmission signals) to one or two layers, and performs precoding. Then, the terminal 20 maps the precoded complex-valued symbols to resource elements to generate transmission signals (e.g., complex-valued time-domain SC-FDMA signals), and transmits them from each antenna port.

[0034] The base station 10 has a cellular communication function as a base station in LTE or NR, and a function for enabling communication of the terminal 20 in this embodiment (e.g., resource pool setting, resource allocation, etc.). The base station 10 may also be an RSU (gNB type RSU).

[0035] Furthermore, in the wireless communication system according to the embodiment of the present invention, the signal waveform used by the terminal 20 for SL or UL may be OFDMA, SC-FDMA, or another signal waveform.

[0036] As a synchronization signal in the SL, the terminal 20 transmits a sidelink synchronization signal block (Sidelink Synchronization Signal / Physical Sidelink Broadcast Channel Block) (S-SSB). The S-SSB may include a sidelink primary synchronization signal (S-PSS), a sidelink secondary synchronization signal (S-SSS), and a physical sidelink broadcast channel (PSBCH). Note that the names S-SSB, S-PSS, S-SSS, etc. are merely examples, and names other than S-SSB, S-PSS, S-SSS, etc. may also be used.

[0037] A terminal 20 transmits an S-SSB to another terminal 20 based on a signal received from a base station device 10, a GNSS (Global Navigation Satellite System) signal, or a signal received from another terminal 20. Note that if the terminal 20 cannot transmit an S-SSB based on any signal from the base station device 10, the GNSS, or another terminal 20, the terminal 20 may transmit an autonomously determined S-SSB to the other terminal 20. Resources available for the S-SSB may be periodic slots, and may be referred to as S-SSB opportunities.

[0038] In step S101, the terminal 20A autonomously selects resources to be used for the PSCCH and the PSSCH from a resource selection window having a predetermined period. The resource selection window may be set in the terminal 20 by the base station 10. Here, the predetermined period of the resource selection window may be defined by implementation conditions of the terminal, such as processing time or maximum allowable packet delay time, or may be defined in advance by specifications, or the predetermined period may be referred to as an interval in the time domain.

[0039] In steps S102 and S103, the terminal 20A transmits SCI (Sidelink Control Information) via the PSCCH and / or PSSCH using the resources autonomously selected in step S101, and transmits SL data via the PSSCH. For example, the terminal 20A may transmit the PSCCH using a time resource that is the same as at least a part of the time resource of the PSSCH, and a frequency resource that may or may not be adjacent to the frequency resource of the PSSCH.

[0040] The terminal 20B receives the SCI (PSCCH and / or PSSCH) and SL data (PSSCH) transmitted from the terminal 20A. The received SCI may include information on the PSFCH resource used by the terminal 20B to transmit a HARQ-ACK in response to reception of the data. The terminal 20A may transmit information on autonomously selected resources by including it in the SCI. Note that the resources available for the PSFCH may be periodic slots and the last symbols in the slots (excluding the final symbol), and may be referred to as PSFCH opportunities.

[0041] In step S104, the terminal 20B uses the PSFCH resource determined from the received SCI to transmit a HARQ-ACK for the received data to the terminal 20A.

[0042] In step S105, if the HARQ-ACK received in step S104 indicates a request for retransmission, that is, if it is a NACK (negative acknowledgement), the terminal 20A retransmits the PSCCH and PSSCH to the terminal 20B. The terminal 20A may retransmit the PSCCH and PSSCH using autonomously selected resources.

[0043] If HARQ control involving HARQ feedback is not performed, steps S104 and S105 may not be performed.

[0044] 3 is a sequence diagram showing an operation example (2) of V2X. Blind retransmission without HARQ control may be performed to improve the transmission success rate or reach.

[0045] In step S201, the terminal 20A autonomously selects resources to be used for the PSCCH and the PSSCH from a resource selection window having a predetermined period. The resource selection window may be set in the terminal 20 by the base station 10.

[0046] In steps S202 and S203, the terminal 20A transmits SCI via the PSCCH and / or PSSCH and transmits SL data via the PSSCH using the resources autonomously selected in step S201. For example, the terminal 20A may transmit the PSCCH using frequency resources adjacent to the frequency resources of the PSSCH in the same time resources as at least a part of the time resources of the PSSCH.

[0047] In step S204, the terminal 20A uses the resources autonomously selected in step S201 to retransmit the SCI via the PSCCH and / or PSSCH and the SL data via the PSSCH to the terminal 20B. The retransmission in step S204 may be performed multiple times.

[0048] If blind retransmission is not performed, step S204 does not have to be performed.

[0049] 4 is a sequence diagram showing an operation example (3) of V2X. The base station 10 may perform sidelink scheduling. That is, the base station 10 may determine sidelink resources to be used by the terminal 20 and transmit information indicating the resources to the terminal 20. Furthermore, when HARQ control involving HARQ feedback is applied, the base station 10 may transmit information indicating PSFCH resources to the terminal 20.

[0050] In step S301, the base station 10 performs SL scheduling by transmitting DCI (Downlink Control Information) via the PDCCH to the terminal 20 A. Hereinafter, for convenience, DCI for SL scheduling will be referred to as SL scheduling DCI.

[0051] Also, in step S301, it is assumed that the base station 10 also transmits DCI for DL ​​scheduling (which may also be called DL allocation) to the terminal 20A via the PDCCH. Hereinafter, for convenience, the DCI for DL ​​scheduling will be referred to as DL scheduling DCI. The terminal 20A that has received the DL scheduling DCI receives DL data via the PDSCH using resources specified in the DL scheduling DCI.

[0052] In steps S302 and S303, the terminal 20A transmits SCI (Sidelink Control Information) via the PSCCH and / or PSSCH using the resources specified in the SL scheduling DCI, and transmits SL data via the PSSCH. Note that the SL scheduling DCI may specify only the resources for the PSSCH. In this case, for example, the terminal 20A may transmit the PSCCH using frequency resources adjacent to the frequency resources for the PSSCH, using the same time resources as at least a portion of the time resources for the PSSCH.

[0053] The terminal 20B receives the SCI (PSCCH and / or PSSCH) and SL data (PSSCH) transmitted from the terminal 20A. The SCI received via the PSCCH and / or PSSCH includes information on the PSFCH resource used by the terminal 20B to transmit a HARQ-ACK in response to reception of the data.

[0054] The resource information is included in the DL scheduling DCI or SL scheduling DCI transmitted from the base station 10 in step S301, and the terminal 20A acquires the resource information from the DL scheduling DCI or SL scheduling DCI and includes it in the SCI. Alternatively, the resource information may not be included in the DCI transmitted from the base station 10, and the terminal 20A may autonomously include the resource information in the SCI and transmit it.

[0055] In step S304, the terminal 20B transmits a HARQ-ACK for the received data to the terminal 20A using the PSFCH resource determined from the received SCI.

[0056] In step S305, the terminal 20A transmits a HARQ-ACK using a PUCCH (Physical uplink control channel) resource specified by the DL scheduling DCI (or the SL scheduling DCI) at a timing (for example, slot-by-slot timing) specified by the DL scheduling DCI (or the SL scheduling DCI), and the base station 10 receives the HARQ-ACK. The HARQ-ACK codebook may include a HARQ-ACK generated based on the HARQ-ACK received from the terminal 20B or the PSFCH that was not received, and a HARQ-ACK for the DL data. However, if no DL data is allocated, for example, a HARQ-ACK for the DL data is not included. In NR Rel. 16, the HARQ-ACK codebook does not include a HARQ-ACK for the DL data.

[0057] Note that if HARQ control involving HARQ feedback is not performed, step S304 and / or step S305 may not be performed.

[0058] FIG. 5 is a sequence diagram showing an operation example (4) of V2X. As described above, in the NR sidelink, it is supported that the HARQ response is transmitted on the PSFCH. Note that the format of the PSFCH can be, for example, the same format as PUCCH (Physical Uplink Control Channel) format 0. That is, the PSFCH format may be a sequence-based format in which the PRB (Physical Resource Block) size is 1 and ACK and NACK are distinguished by differences in sequence and / or cyclic shift. The PSFCH format is not limited to this. The PSFCH resource may be allocated to the last symbol or the last multiple symbols of a slot. Furthermore, a period N is set or predefined for the PSFCH resource. The period N may be set or predefined on a slot-by-slot basis.

[0059] In FIG. 5 , the vertical axis corresponds to the frequency domain, and the horizontal axis corresponds to the time domain. The PSCCH may be placed in the first symbol of a slot, or in multiple symbols from the first, or in multiple symbols from symbols other than the first. The PSFCH may be placed in the last symbol of a slot, or in multiple symbols from the last. Note that the above-mentioned "first symbol of a slot" and "last symbol of a slot" may not take into account symbols for AGC (Automatic Gain Control) and symbols for transmission / reception switching. That is, for example, if one slot consists of 14 symbols, the "first symbol of a slot" and the "last symbol of a slot" may refer to the first and last symbols, respectively, of the 12 symbols excluding the first and last symbols. In the example shown in FIG. 5 , three subchannels are configured in the resource pool, and two PSFCHs are placed three slots after the slot in which the PSSCH is placed. The arrow from the PSSCH to the PSFCH indicates an example of a PSFCH associated with the PSSCH.

[0060] When the HARQ response in NR-V2X groupcast is groupcast option 2, which transmits an ACK or NACK, it is necessary to determine the resources to be used for transmitting and receiving the PSFCH. As shown in FIG. 5, in step S401, terminal 20A, which is the transmitting terminal 20, performs groupcast to terminals 20B, 20C, and 20D, which are receiving terminals 20, via SL-SCH (Sidelink Shared Channel). In the following step S402, terminal 20B uses PSFCH#B, terminal 20C uses PSFCH#C, and terminal 20D uses PSFCH#D to transmit a HARQ response to terminal 20A. Here, as shown in the example of FIG. 5, if the number of available PSFCH resources is less than the number of receiving terminals 20 belonging to the group, it is necessary to determine how to allocate the PSFCH resources. Note that the transmitting terminal 20 may be aware of the number of receiving terminals 20 in the groupcast. In groupcast option 1, only NACK is transmitted as the HARQ response, and ACK is not transmitted.

[0061] FIG. 6 is a diagram showing an example of sensing operation in NR. In resource allocation mode 2, a terminal 20 selects a resource and transmits. As shown in FIG. 6, the terminal 20 performs sensing in a sensing window within a resource pool. Through sensing, the terminal 20 receives a resource reservation field or a resource assignment field included in an SCI transmitted from another terminal 20, and identifies available resource candidates within a resource selection window within the resource pool based on the field. Then, the terminal 20 randomly selects a resource from the available resource candidates.

[0062] 6, the resource pool configuration may have a period. For example, the period may be 10240 milliseconds. ０ ＳＬ From slot t Ｔｍａｘ－１ ＳＬ In this example, the resource pool is set up to the period. The resource pool in each period may have an area set by, for example, a bitmap.

[0063] As shown in FIG. 6, the transmission trigger in the terminal 20 occurs in slot n, and the priority of the transmission is p ＴＸ The terminal 20 receives the data in slot nT. ０ From slot n-T ｐｒｏｃ，０ In the sensing window up to the slot immediately before the priority p ＲＸWhen an SCI is detected in a sensing window and the RSRP (Reference Signal Received Power) is greater than a threshold, the resource in the resource selection window corresponding to the SCI is excluded. When an SCI is detected in a sensing window and the RSRP is less than a threshold, the resource in the resource selection window corresponding to the SCI is not excluded. The threshold may be, for example, a priority p ＴＸ and priority p ＲＸ A threshold Th is set or defined for each resource in the sensing window based on ｐＴＸ，ｐＲＸ may be.

[0064] Also, the slot t shown in FIG. ｍ ＳＬ As such, resources in the resource selection window that are candidates for resource reservation information corresponding to resources in the sensing window that were not monitored, for example for transmission, are excluded.

[0065] Slot n+T １ In the resource selection window from slot n to slot n+T2, resources occupied by other UEs are identified, and resources excluding these resources are used as available resource candidates, as shown in FIG. Ａ Then, S Ａ is less than 20% of the resource selection window, the threshold Th ｐＴＸ，ｐＲＸ The threshold Th may be increased by 3 dB and resource identification may be performed again. ｐＴＸ，ｐＲＸ By increasing the number of resources that are not excluded because the RSRP is less than the threshold, the set of resource candidates S Ａ may be set to be 20% or more of the resource selection window. Ａ is less than 20% of the resource selection window, the threshold Th ｐＴＸ，ｐＲＸ The operation of increasing the signal level by 3 dB and performing resource identification again may be repeated.

[0066] The lower layer of the terminal 20 is S Ａ The upper layer of the terminal 20 may report S Ａ The terminal 20 may determine the resources to be used by performing a random selection on the upper layer. The terminal 20 may perform the sidelink transmission using the determined resources. For example, the upper layer may be a MAC layer, and the lower layer may be a PHY layer or a physical layer.

[0067] In the above-mentioned Figure 6, the operation of the transmitting terminal 20 is explained, but the receiving terminal 20 may detect data transmission from another terminal 20 based on the results of sensing or partial sensing, and receive data from the other terminal 20.

[0068] FIG. 7 is a flowchart showing an example of preemption in NR. FIG. 8 is a diagram showing an example of preemption in NR. In step S501, the terminal 20 performs sensing in a sensing window. If the terminal 20 performs a power-saving operation, the sensing may be performed in a predefined limited period. Next, the terminal 20 identifies each resource in the resource selection window based on the sensing result to generate a set of resource candidates S Ａ Then, the terminal 20 determines a set of resource candidates S Ａ A resource set (r_0, r_1, ...) for determining whether preemption has occurred is selected from the resource set (r_0, r_1, ...) (S503). The resource set may be notified to the PHY layer from an upper layer as the resource for determining whether preemption has occurred.

[0069] In step S504, the terminal 20 calculates T(r_0)-T ３ At the timing, each resource in the resource selection window is identified again based on the sensing result to generate a set of resource candidates S Ａ , and further determines preemption for the resource set (r_0, r_1, ...) based on the priority. For example, in r_1 shown in FIG. 8, SCI transmitted from another terminal 20 is detected by re-sensing, and S Ａis not included in the value prio_RX. When preemption is enabled, if the value prio_RX indicating the priority of the SCI transmitted from the other terminal 20 is lower than the value prio_TX indicating the priority of the transport block transmitted from the terminal itself, the terminal 20 determines that the resource r_1 has been preempted. Note that the lower the value indicating the priority, the higher the priority. In other words, if the value prio_RX indicating the priority of the SCI transmitted from the other terminal 20 is higher than the value prio_TX indicating the priority of the transport block transmitted from the terminal itself, the terminal 20 determines that the resource r_1 has been preempted. Ａ , pl_1, pl_2, ..., pl_3), this priority is set as prio_pre. At this time, if the value prio_RX indicating the priority of the SCI transmitted from the other terminal 20 is lower than prio_pre and prio_RX is lower than the value prio_TX indicating the priority of the transport block transmitted from the terminal 20 itself, the terminal 20 determines that the resource r_1 has been preempted.

[0070] In step S505, if preemption is determined in step S504, the terminal 20 notifies the upper layer of preemption, causes the upper layer to reselect resources, and ends the preemption check.

[0071] In addition, when re-evaluation is performed instead of checking preemption, in step S504, the set of resource candidates S Ａ After determining S Ａ If the resource set (r_0, r_1, . . . ) is not included in the resource set, the resource is not used and a resource reselection is performed in the upper layer.

[0072] FIG. 9 is a diagram illustrating an example of partial sensing operation in LTE. When partial sensing is configured by a higher layer in the LTE sidelink, the terminal 20 selects resources and performs transmission as shown in FIG. 9. As shown in FIG. 9, the terminal 20 performs partial sensing on a portion of the sensing window, i.e., a sensing target, in a resource pool. With partial sensing, the terminal 20 receives a resource reservation field included in an SCI transmitted from another terminal 20 and identifies available resource candidates in the resource selection window in the resource pool based on the field. Then, the terminal 20 randomly selects a resource from the available resource candidates.

[0073] FIG. 9 shows the subframe t ０ ＳＬ From subframe t Ｔｍａｘ－１ ＳＬ In this example, up to subframe n+T is set as a resource pool. The target area of ​​the resource pool may be set by, for example, a bitmap. As shown in FIG. 9, it is assumed that a transmission trigger occurs in terminal 20 in subframe n+T. １ From subframe n to subframe n+T, subframe t ｙ１ ＳＬ From subframe t ｙＹ ＳＬ Y subframes up to may be set as the resource selection window.

[0074] The terminal 20 receives the subframe ty1-k×P step, which has a length of Y subframes. ＳＬ From subframe tyY-k×Pstep ＳＬ For example, it is possible to detect that another terminal 20 is transmitting in one or more sensing targets up to k. k may be determined by a 10-bit bitmap, for example. FIG. 9 shows an example in which the third and sixth bits of the bitmap are set to "1" indicating that partial sensing is performed. That is, in FIG. 9, in the subframe ty1-6×Pstep ＳＬ From subframe tyY-6×Pstep ＳＬUp to subframe ty1-3×Pstep ＳＬ From subframe tyY-3×Pstep ＳＬ As described above, the k-th bit of the bitmap is set to the subframe ty1-k×Pstep ＳＬ From subframe tyY-k×Pstep ＳＬ It may correspond to a sensing window up to y ｉ corresponds to the index (1...Y) in the Y subframe.

[0075] Note that k is set in a 10-bit bitmap or is predefined, and P ｓｔｅｐ However, when SL communication is performed on DL and UL carriers, P ｓｔｅｐ may be (U / (D+S+U))*100 ms, where U corresponds to the number of UL subframes, D corresponds to the number of DL subframes, and S corresponds to the number of special subframes.

[0076] When SCI is detected in the sensing target and the RSRP is greater than a threshold, the resource in the resource selection window corresponding to the resource reservation field of the SCI is excluded. When SCI is detected in the sensing target and the RSRP is less than a threshold, the resource in the resource selection window corresponding to the resource reservation field of the SCI is not excluded. The threshold may be, for example, a sender priority p ＴＸ and receiver priority p ＲＸ Based on this, a threshold Th is set or defined for each resource in the sensing target. ｐＴＸ，ｐＲＸ may be.

[0077] As shown in FIG. １ , n+T ２ In the resource selection window set in the Y subframe of

[0000] , the terminal 20 identifies resources occupied by other UEs, and the resources excluding these resources become available resource candidates. Note that the Y subframes do not have to be consecutive. The set of available resource candidates is denoted by S Ａ Then, S Ａis less than 20% of the resources in the resource selection window, the threshold Th ｐＴＸ，ｐＲＸ may be increased by 3 dB and resource identification may be performed again.

[0078] That is, the threshold value Th ｐＴＸ，ｐＲＸ By increasing S and performing resource identification again, the number of resources that are not excluded because their RSRP is below the threshold may be increased. Ａ Measure the RSSI of each resource in the set S. Ｂ The set of resource candidates S Ｂ until S is greater than or equal to 20% of the resource selection window. Ａ The resource with the smallest RSSI included in Ｂ The operation of adding to may be repeated.

[0079] The lower layer of the terminal 20 is S Ｂ The upper layer of the terminal 20 may report S Ｂ The terminal 20 may determine the resource to be used by randomly selecting the resource. The terminal 20 may perform sidelink transmission using the determined resource. Note that, after once reserving the resource, the terminal 20 may select the resource a predetermined number of times (e.g., C ｒｅｓｅｌ The resource may be used periodically without sensing for a period of time (times).

[0080] In the NR sidelink, power saving based on random resource selection and partial sensing is specified. A terminal 20 to which partial sensing is applied performs reception and sensing only in specific slots within a sensing window. That is, the terminal 20 may perform partial sensing, which identifies resources by sensing only limited resources compared to full sensing, and selects resources from the identified resource set. Alternatively, the terminal 20 may perform random selection, which sets the resources within the resource selection window as an identified resource set without excluding resources from the resources within the resource selection window, and selects resources from the identified resource set.

[0081] Note that a method of performing random selection at the time of resource selection and using sensing information at the time of reevaluation or preemption check may be treated as partial sensing or as random selection.

[0082] Note that the following 1) and 2) may be applied as operations in sensing. Note that sensing and monitoring may be interchangeable, and the operations may include at least one of measuring received RSRP, obtaining reservation resource information, and obtaining priority information.

[0083] 1) Periodic-based partial sensing: In a mechanism where sensing is performed only on some slots, sensing slots are determined based on a reservation periodicity. Note that the reservation period is a value related to the resource reservation period field. Note that the term "period" may be replaced with "periodicity."

[0084] 2) Contiguous partial sensing: In a mechanism where sensing is performed only on some slots, sensing slots are determined based on aperiodic reservation, where the aperiodic reservation is a value associated with the time resource assignment field.

[0085] In addition, multiple resource allocation methods can be configured for a resource pool. Also, as one of the power-saving functions, SL-DRX (Discontinuous Reception) is supported. That is, reception is performed only during a predetermined time period.

[0086] As described above, partial sensing is supported as one of the power saving functions. In a resource pool in which partial sensing is configured, the terminal 20 may perform the above-described periodic partial sensing. The terminal 20 may receive, from the base station 10, information for configuring a resource pool in which partial sensing is configured and periodic reservation is enabled.

[0087] 10 is a diagram illustrating an example of periodic partial sensing. As shown in FIG. 10, Y candidate slots for resource selection are defined within a resource selection window [n+T １ , n+T ２ ] to select from.

[0088] t ｙ ＳＬ is one of the slots included in the Y candidate slots, and ty-k × Preserve ＳＬ may be used as a target slot for periodic partial sensing.

[0089] P ｒｅｓｅｒｖｅ may correspond to all values ​​contained in a configured or predefined set sl-ResourceReservePeriodList. Alternatively, P may be limited to a subset of sl-ResourceReservePeriodList. ｒｅｓｅｒｖｅ The value of P may be set or predefined. ｒｅｓｅｒｖｅThe sl-ResourceReservePeriodList and sl-ResourceReservePeriodList may be configured for each transmission resource pool of resource allocation mode 2. Furthermore, the UE may implement monitoring of periods included in the sl-ResourceReservePeriodList other than the limited subset. For example, the terminal 20 may additionally monitor opportunities corresponding to P_RSVP_Tx.

[0090] Regarding the k value, the terminal 20 may monitor the most recent sensing opportunity in a certain reservation period before slot n of the resource selection trigger or before the first slot of Y candidate slots subject to processing time limitations. The terminal 20 may also additionally monitor periodic sensing opportunities corresponding to a set of one or more k values. For example, the k value may be set to a value corresponding to the most recent sensing opportunity in a certain reservation period before slot n of the resource selection trigger or before the first slot of Y candidate slots subject to processing time limitations, and a value corresponding to the sensing opportunity immediately before the most recent sensing opportunity in the certain reservation period.

[0091] As described above, partial sensing is supported as one of the power saving functions. In a resource pool in which partial sensing is configured, the terminal 20 may perform the above-described continuous partial sensing. The terminal 20 may receive, from the base station 10, information for configuring a resource pool in which partial sensing is configured and aperiodic reservation is enabled.

[0092] 11 is a diagram illustrating an example of continuous partial sensing. As shown in FIG. 11, when a trigger for resource selection is slot n, terminal 20 selects Y candidate slots for resource selection within a resource selection window [n+T １ , n+T ２ 11 shows an example in which Y=7. As shown in FIG. 11, the beginning of the Y candidate slots is selected as slot t ｙ１ Let the next slot be t ｙ２ ..., the end of the Y candidate slots is slot t ｙＹ It is written as follows.

[0093] The terminal 20 is Ａ , n+T Ｂ ] and sensing is performed at n+T Ｂ or n+T Ｂ From then on (n+T Ｃ The resource selection is performed in the interval [n+T Ａ , n+T Ｂ ]T Ａ and T Ｂ can be any value, and n can be replaced with the index of any of the Y candidate slots.

[0094] Furthermore, the symbol [ may be replaced with the symbol (and the symbol ] may be replaced with the symbol). For example, the interval [a, b] is the interval from slot a to slot b, and includes slot a and slot b. For example, the interval (a, b) is the interval from slot a to slot b, and does not include slot a and slot b.

[0095] The candidate resource to be selected is referred to as Y candidate slots. １ , n+T ２ ] may be all candidate slots, or some of the slots may be candidate slots.

[0096] Furthermore, inter-terminal coordination has been specified as a method for improving reliability and delay performance. For example, the inter-terminal coordination method 1 and inter-terminal coordination method 2 shown below have been specified. Hereinafter, the terminal 20 that transmits coordination information will be referred to as UE-A, and the terminal 20 that receives the coordination information will be referred to as UE-B.

[0097] Inter-UE coordination method 1) For transmission by UE-B, a preferred resource set and / or a non-preferred resource set is transmitted from UE-A to UE-B. Hereinafter, inter-UE coordination method 1 is also referred to as IUC scheme 1 (Inter-UE coordination scheme 1).

[0098] Inter-UE coordination method 2) UE-A transmits to UE-B information indicating resources indicated by the SCI received from UE-B where collision with other transmission or reception is expected and / or where collision has been detected. This information may be transmitted via the PSFCH. Hereinafter, inter-UE coordination method 2 is also referred to as IUC scheme 2 (Inter-UE coordination scheme 2).

[0099] The 3GPP Release 16 or Release 17 sidelink is specified for the following 1) and 2).

[0100] 1) An environment in which only 3GPP terminals exist in the ITS (Intelligent Transport Systems) band. 2) An environment in which UL resources are available for SL in the licensed bands of FR1 (Frequency range 1) and FR2 defined by NR.

[0101] It is being considered to newly include unlicensed bands as sidelinks in 3GPP Release 18 and later. For example, unlicensed bands such as the 5 GHz-7 GHz band and the 60 GHz band are included.

[0102] Figure 12 is a diagram showing an example of frequency bands used in a wireless communication system. In the NR specifications of 3GPP Release 15 and Release 16, for example, operation of a frequency band of 52.6 GHz or higher is being considered. As shown in Figure 12, the FR (Frequency range) 1 currently specified for operation is a frequency band from 410 MHz to 7.125 GHz, the SCS (Subcarrier spacing) is 15, 30, or 60 kHz, and the bandwidth is from 5 MHz to 100 MHz.

[0103] FR2-1 is the frequency band from 24.25 GHz to 52.6 GHz, and SCS uses 60, 120, or 240 kHz, with a bandwidth of 50 MHz to 400 MHz. As shown in Figure 12, FR2-2 may be assumed to be from 52.6 GHz to 71 GHz. Furthermore, it may be assumed to support frequency bands above 71 GHz.

[0104] When using a band above 52.6 GHz, Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) / Discrete Fourier Transform - Spread (DFT-S-OFDM) with larger Sub-Carrier Spacing (SCS) may be applied.

[0105] Additionally, in high frequency bands such as FR2-2, increased phase noise between carriers becomes an issue, which may necessitate the application of a larger (wider) SCS or single carrier waveform.

[0106] For example, examples of unlicensed bands in the 5 GHz-7 GHz band include 5.15 GHz to 5.35 GHz, 5.47 GHz to 5.725 GHz, and 5.925 GHz and above.

[0107] For example, examples of unlicensed bands in the 60 GHz band include 59 GHz to 66 GHz, 57 GHz to 64 GHz or 66 GHz, and 59.4 GHz to 62.9 GHz.

[0108] In unlicensed bands, various regulations are established to prevent interference with other systems or other devices.

[0109] For example, in the 5 GHz-7 GHz band, LBT (Listen before talk) is performed when accessing a channel. The base station 10 or terminal 20 performs power detection for a predetermined period immediately before transmitting, and if the power exceeds a certain value, i.e., if transmission from another device is detected, the transmission is halted (this may be called an LBT failure). In addition, a maximum channel occupancy time (MCOT) is specified. MCOT is the maximum time period during which transmission is allowed to continue if transmission is started after LBT, and is, for example, 4 ms in Japan. If channel access is successful, it may be assumed that COT (Channel occupancy time) has been acquired, and transmission is performed during COT.

[0110] In addition, the occupied channel bandwidth (OCB) requirement states that when a transmission uses a certain carrier bandwidth, it must use at least X% of that bandwidth. For example, in Europe, it is required to use 80% to 100% of the nominal channel bandwidth (NCB). The OCB requirement aims to ensure that power detection for channel access is performed correctly.

[0111] Regarding maximum transmission power and maximum power spectral density (PSD), in order to avoid excessive interference, transmission must be performed at or below a certain transmission power. For example, in Europe, the maximum transmission power is 23 dBm in the 5150 MHz-5350 MHz band. Also, in Europe, the maximum power spectral density is 10 dBm / MHz in the 5150 MHz-5350 MHz band.

[0112] For example, in the 60 GHz band, LBT is performed when accessing a channel. The base station 10 or terminal 20 performs power detection for a predetermined period immediately before transmitting, and if the power exceeds a certain value, i.e., if transmission from another device is detected, the transmission is stopped. Furthermore, it is specified that transmission is performed at or below a predetermined transmission power with respect to the maximum transmission power and maximum power spectral density. It is also specified that the device must have the ability to satisfy the OCB requirements.

[0113] In NR, the following four types of channel access procedures are defined based on the differences in the time behavior of LBT (the period during which sensing is performed). Note that this sensing is a different operation from the above-mentioned sidelink sensing, and is described as LBT sensing for the sake of distinction. Note that "LBT" and "channel access procedure" may be interchangeable.

[0114] Type 1) Performs variable-time LBT sensing before transmission. Also known as Category 4 LBT. Type 2A) Performs 25 μs LBT sensing before transmission. Also known as Category 2 LBT. Type 2B) Performs 16 μs LBT sensing before transmission. Also known as Category 2 LBT. Type 2C) Starts transmission without LBT. Similar to licensed band transmission.

[0115] FIG. 13 is a diagram for explaining an example of LBT (1). FIG. 13 shows an example of a channel access procedure of Type 1. Type 1 is further classified into four classes indicating channel access priority classes (CAPC) based on differences in LBT sensing length. LBT sensing is performed in the following two periods:

[0116] The first period is the prioritization period or defer duration, which is 16 + 9 × m ｐ It has a length of [μs]. ｐ A fixed value is specified for each channel access priority class.

[0117] The second period is a backoff procedure with a length of 9 × N [μs]. The value of N is randomly determined from a certain range (see the CWS adjustment procedure in Non-Patent Document 4). N is the initial value of the backoff counter, and the value of the backoff counter is decreased by 1 each time the power of a signal from another device is not detected within 9 [μs].

[0118] In the above, the 9 μs LBT sensing period may be referred to as the LBT sensing slot period.

[0119] In the example of FIG. ｐ = 3, and the hold period is 43 μs. As shown in Figure 13, the backoff counter is fixed while the channel is busy. Also, as shown in Figure 13, if transmissions from the NR-U gNB and wireless LAN node #2 collide and an error is detected, the contention window size (CWS) is expanded from 3 to 13 in the NR-U gNB.

[0120] Fig. 14 is a diagram for explaining an example (2) of LBT. Fig. 14 shows an example of a channel access procedure of Type 2A or Type 2B without random backoff. A gap for power detection of 25 μs is set before transmission for Type 2A, and a gap for power detection of 16 μs is set for Type 2B.

[0121] Figure 15 is a diagram for explaining an example of LBT (3). Figure 15 is an example of a Type 2C channel access procedure. As shown in Figure 15, power detection is not performed before transmission, and transmission is performed immediately after a gap not exceeding 16 μs. The transmission period may be up to 584 μs.

[0122] As mentioned above, multiple LBT types are supported in NR-U. In the above type 1, the initial value N of the backoff counter ranges from 0 to CW, whose value range is determined based on the channel access priority class p. ｐ Table 1 shows the m defined for each channel access priority class p in the UL. ｐ , C.W. ｐ The minimum value of CW ｐ，ｍｉｎ , C.W. ｐThe maximum value of CW ｐ，ｍａｘ Here is an example:

[0123]

[0124] As shown in Table 1, the channel access priority class p determines the ｐ , C.W. ｐ，ｍｉｎ , C.W. ｐ，ｍａｘ is determined. When p is 1, the LBT period calculated from Table 1 is a minimum of 34 μs and a maximum of 88 μs. When p is 2, the LBT period calculated from Table 1 is a minimum of 34 μs and a maximum of 160 μs. When p is 3, the LBT period calculated from Table 1 is a minimum of 43 μs and a maximum of 9286 μs. When p is 4, the LBT period calculated from Table 1 is a minimum of 79 μs and a maximum of 9286 μs. Table 1 is a table used for UL.

[0125] The LBT type and the channel access priority class may be determined based on a notification from the base station 10, a channel type, etc. The 25 μs or 16 μs gap may be set by the base station 10 scheduling, taking into account TA (Timing Advance) and CP extension.

[0126] The LBT applied to channel access is performed for each predetermined bandwidth (e.g., 20 MHz). If no power is detected in the LBT channel containing each transmission, the transmission can be performed. On the other hand, each CC in Uu can be defined with a bandwidth wider than the LBT channel. In other words, wideband operation is supported. Note that Uu is the radio interface between the Universal Terrestrial Radio Access Network (UTRAN) and User Equipment (UE).

[0127] Figure 16 is a diagram for explaining an example (1) of wideband operation. Figure 17 is a diagram for explaining an example (2) of wideband operation. In the case of wideband operation in an unlicensed band, as shown in Figure 16 or Figure 17, when LBT in a gNB is successful in some or all of the LBT channels, transmission may be permitted in the LBT channel in which LBT was successful. As shown in Figure 16, the gNB may transmit a single continuous block, or as shown in Figure 17, the gNB may transmit multiple discontinuous blocks.

[0128] For DL ​​in unlicensed bands, DL Type A is specified, which performs LBT on each channel, and DL Type B, which performs LBT Type 1 on randomly selected channels and LBT Type 2A on the remaining channels.

[0129] DL Type A is further classified into Type A1 and Type A2. In Type A1, the contention window CWp is determined for each channel. In Type A2, the largest CWp among the CWp determined for each channel is used.

[0130] DL Type B is further classified into Type B1 and Type B2. In Type B1, a single CWp is applied to all channels. In Type B2, the largest CWp among the CWp determined for each channel is used.

[0131] If some or all of the LBT channels in the gNB are successful in LBT, PDSCH transmission is permitted on the LBT channels where LBT was successful. The gNB may transmit a single block that is continuous in the frequency direction, or may transmit multiple blocks that are discontinuous in the frequency direction.

[0132] Figure 18 is a diagram for explaining an example (3) of wideband operation. Figure 19 is a diagram for explaining an example (4) of wideband operation. As shown in Figure 18 or Figure 19, when LBT in the UE is successful in all LBT channels in the scheduled band, transmission may be permitted. As shown in Figure 19, when LBT fails in some LBT channels, transmission may not be permitted.

[0133] For UL in unlicensed bands, the LBT type is determined by instructions from the gNB. When LBT type 1 is instructed, if an LBT similar to DL type B is performed on the UL immediately before transmission, LBT type 2 is applied, or LBT type 1 is applied. If LBT fails on any of the LBT channels for transmission, UL is not transmitted on all LBT channels. Note that the LBT channel may also be called an RB (Resource Block) set. The LBT channel and the RB set may be interchangeable.

[0134] In SL-U (Sidelink Unlicensed), LBT is performed in the same way as in NR-U (NR Unlicensed). In Type 1 LBT, the time interval for performing LBT is determined based on the Channel Access Priority Class (CAPC). Table 2 shows an example of the time interval for LBT determined by CAPC in the sidelink (see Non-Patent Document 4).

[0135]

[0136] When sidelink transmission including PSCCH or PSSCH, for example, PSCCH or PSSCH, S-SSB, and PSCCH or PSSCH are transmitted in sequence, the CAPC of PSCCH or PSSCH is referenced to determine the time interval of Type 1 LBT. Note that as long as PSCCH or PSSCH is included in the series of transmissions, the order may be any. Also, when only PSFCH or only S-SSB is transmitted, it is specified that the CAPC referenced to determine the time interval of Type 1 LBT is 1.

[0137] 20 is a diagram for explaining an example of transmission in an embodiment of the present invention. As shown in FIG. 20, a method for determining CAPC when performing Type 1 LBT on only PSFCH and S-SSB to acquire COT has not been specified.

[0138] Therefore, when performing a Type 1 channel access procedure for sidelink transmission including PSFCH and S-SSB but not including PSCCH or PSSCH, the UE may apply CAPC as shown in 1)-6) below. Note that the embodiments of the present invention may also be applied to cases where COT is acquired for sidelink transmission including PSFCH and S-SSB but not including PSCCH or PSSCH. Furthermore, the embodiments of the present invention may also include a sidelink positioning reference signal (SL-PRS).

[0139] 1) The CAPC may be a fixed value (1, 2, 3, or 4). 2) The CAPC may be a value corresponding to the (e.g., smallest) COT size at which the sidelink transmission can be transmitted. 3) The CAPC may be pre-configured, configured, or signaled. 4) The CAPC may be determined based on past transmission results (e.g., ACK or NACK) and / or past LBT results (e.g., success or failure). 5) The CAPC may be determined by the UE. 6) The CAPC may be associated with the PSCCH or PSSCH corresponding to the PSFCH. For example, the CAPC may be the CAPC of the PSCCH or PSSCH corresponding to the PSFCH.

[0140] 21 is a flowchart for explaining an example of transmission in an embodiment of the present invention. In step S601, the UE determines the LBT to be applied to Type 1 LBT when transmitting only PSFCH and S-SSB. In step S602, if Type 1 LBT is successful, the UE transmits PSFCH and S-SSB.

[0141] Although the above-described embodiment uses a conventional SL channel and SL signal configuration, the present invention is not limited to this. For example, the present embodiment may also be applied to a case where an interlaced channel is used as a configuration to satisfy the OCB requirements.

[0142] Note that the above-described embodiment may be applied only when a predetermined condition is satisfied. For example, it may be applied in relation to a predetermined SL channel or SL signal. For example, this embodiment may be applied to any of the PSCCH / PSSCH, PSFCH, S-SSB, and SL positioning RS. For example, this embodiment may be applied based on a predetermined setting or pre-configuration. For example, this embodiment may be applied when "enabling" this embodiment in a resource pool is provided by a setting or pre-configuration. For example, this embodiment may not be applied when the LBT method for the second SL transmission is not or is no longer Type 1.

[0143] In addition, in order to apply LBT type 2A, 2B or 2C, an additional transmission (additional TX), such as CP extension, may be performed immediately before transmission.

[0144] In addition, UE capabilities related to the applicability and operation of this embodiment may be defined, and may or may not be reported to the base station 10 and / or the terminal 20.

[0145] The SL transmission of the UE may be any of PSCCH, PSSCH, PSFCH, S-SSB, and SL-PRS, and different channels or signals may be applied to each operation of this embodiment.

[0146] Note that at least one of the SL transmissions of the UE may be an UL transmission.

[0147] This embodiment may be applied to any of resource selection, resource reselection, reevaluation, and preemption check.

[0148] The method according to the embodiment of the present invention is not limited to the case of direct communication between terminals described above, but may be applied to other similar cases.

[0149] The above-described embodiment is not limited to V2X terminals, and may be applied to terminals that perform D2D communication.

[0150] The above embodiment clarifies the UE operation when performing Type 1 LBT to obtain COT for transmitting only PSFCH and S-SSB, and enables transmission of PSFCH and S-SSB.

[0151] That is, in the unlicensed band, it is possible to determine the CAPC (Channel access priority class) to be applied to LBT (Listen before talk).

[0152] (Device Configuration) Next, a functional configuration example of the base station 10 and the terminal 20 that execute the processes and operations described above will be described. The base station 10 and the terminal 20 include functions for implementing the above-described embodiments. However, the base station 10 and the terminal 20 may each include only a part of the functions of the embodiments.

[0153] <Base Station 10> Fig. 22 is a diagram showing an example of the functional configuration of the base station 10. As shown in Fig. 22, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Fig. 22 is merely an example. The names of the functional divisions and functional units may be any as long as they can execute the operations related to the embodiment of the present invention.

[0154] The transmitter 110 has a function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The receiver 120 has a function of receiving various signals transmitted from the terminal 20 and acquiring, for example, information of a higher layer from the received signal. The transmitter 110 also has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, DL reference signals, etc. to the terminal 20.

[0155] The setting unit 130 stores in a storage device setting information that is set in advance and various setting information to be transmitted to the terminal 20, and reads out the setting information from the storage device as needed. The content of the setting information is, for example, information related to the setting of D2D communication.

[0156] As described in the embodiments, the control unit 140 performs processing related to settings for the terminal 20 to perform D2D communication. Furthermore, the control unit 140 transmits scheduling for D2D communication and DL communication to the terminal 20 via the transmission unit 110. Furthermore, the control unit 140 receives information related to HARQ responses for D2D communication and DL communication from the terminal 20 via the reception unit 120. A functional unit related to signal transmission in the control unit 140 may be included in the transmission unit 110, and a functional unit related to signal reception in the control unit 140 may be included in the reception unit 120.

[0157] <Terminal 20> Fig. 23 is a diagram showing an example of the functional configuration of the terminal 20. As shown in Fig. 23, the terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in Fig. 23 is merely an example. The names of the functional divisions and functional units may be any as long as they can execute the operations related to the embodiment of the present invention.

[0158] The transmitter 210 creates a transmission signal from transmission data and transmits the transmission signal wirelessly. The receiver 220 wirelessly receives various signals and acquires higher layer signals from the received physical layer signals. The receiver 220 also has a function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signals or reference signals transmitted from the base station 10. For example, the transmitter 210 transmits a PSCCH (Physical Sidelink Control Channel), a PSSCH (Physical Sidelink Shared Channel), a PSDCH (Physical Sidelink Discovery Channel), a PSBCH (Physical Sidelink Broadcast Channel), or the like to another terminal 20 as D2D communication, and the receiver 220 receives the PSCCH, PSSCH, PSDCH, or PSBCH from the other terminal 20.

[0159] The setting unit 230 stores various pieces of setting information received from the base station 10 or the terminal 20 by the receiving unit 220 in a storage device and reads the information from the storage device as needed. The setting unit 230 also stores setting information that is set in advance. The content of the setting information is, for example, information related to the setting of D2D communication.

[0160] As described in the embodiments, the control unit 240 controls D2D communication that establishes an RRC connection with another terminal 20. The control unit 240 also performs processing related to power saving operation. The control unit 240 also performs processing related to HARQ for D2D communication and DL communication. The control unit 240 also transmits, to the base station 10, information related to HARQ responses for D2D communication and DL communication to another terminal 20 scheduled by the base station 10. The control unit 240 may also schedule D2D communication for the other terminal 20. The control unit 240 may also autonomously select resources to be used for D2D communication from a resource selection window based on the results of sidelink sensing, or may perform reevaluation or preemption. The control unit 240 also performs processing related to power saving in transmission and reception of D2D communication. The control unit 240 also performs processing related to inter-terminal coordination in D2D communication. The control unit 240 also performs processing related to LBT in D2D communication. The functional units in the control unit 240 related to signal transmission may be included in the transmitting unit 210 , and the functional units in the control unit 240 related to signal reception may be included in the receiving unit 220 .

[0161] (Hardware Configuration) The block diagrams (FIGS. 22 and 23) used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining software with the single device or the multiple devices.

[0162] Functions include, but are not limited to, judgment, determination, assessment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0163] For example, the base station 10, the terminal 20, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 24 is a diagram illustrating an example of the hardware configuration of the base station 10 and the terminal 20 according to an embodiment of the present disclosure. The base station 10 and the terminal 20 described above may be physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0164] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the base station 10 and the terminal 20 may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0165] Each function in the base station 10 and the terminal 20 is realized by loading specified software (programs) onto hardware such as the processor 1001, the memory device 1002, etc., so that the processor 1001 performs calculations, controls communication by the communication device 1004, and controls at least one of reading and writing data in the memory device 1002 and the auxiliary memory device 1003.

[0166] The processor 1001 controls the entire computer by running, for example, an operating system. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, the above-mentioned control unit 140, control unit 240, etc. may be realized by the processor 1001.

[0167] Furthermore, the processor 1001 reads programs (program codes), software modules, data, etc. from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002 and executes various processes in accordance with the programs. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 140 of the base station 10 shown in FIG. 22 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. Furthermore, for example, the control unit 240 of the terminal 20 shown in FIG. 23 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. While the above-described various processes have been described as being executed by one processor 1001, they may also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may also be transmitted from a network via a telecommunications line.

[0168] The storage device 1002 is a computer-readable recording medium and may be configured, for example, by at least one of a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), etc. The storage device 1002 may also be called a register, a cache, a main memory, etc. The storage device 1002 can store executable programs (program codes), software modules, etc. for implementing a communication method according to an embodiment of the present disclosure.

[0169] The secondary storage device 1003 is a computer-readable recording medium, and may be, for example, at least one of an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, etc. The above-mentioned storage medium may be, for example, a database, a server, or other appropriate medium including at least one of the storage device 1002 and the secondary storage device 1003.

[0170] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, a transmission / reception antenna, an amplifier unit, a transmission / reception unit, a transmission path interface, etc. may be realized by the communication device 1004. The transmission / reception unit may be implemented as a transmission unit and a reception unit that are physically or logically separated.

[0171] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, an LED lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0172] Furthermore, each device such as the processor 1001 and the storage device 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0173] Furthermore, the base station 10 and the terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0174] Fig. 25 shows an example configuration of a vehicle 2001. As shown in Fig. 25, the vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. Each aspect / embodiment described in the present disclosure may be applied to a communication device mounted on the vehicle 2001, and may be applied to the communication module 2013, for example.

[0175] The drive unit 2002 is configured, for example, by an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel operated by the user.

[0176] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals are input to the electronic control unit 2010 from various sensors 2021 to 2029 provided in the vehicle 2001. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0177] The signals from the various sensors 2021 to 2029 include a current signal from a current sensor 2021 that senses the current of the motor, a rotation speed signal of the front and rear wheels obtained by a rotation speed sensor 2022, an air pressure signal of the front and rear wheels obtained by an air pressure sensor 2023, a vehicle speed signal obtained by a vehicle speed sensor 2024, an acceleration signal obtained by an acceleration sensor 2025, an accelerator pedal depression amount signal obtained by an accelerator pedal sensor 2029, a brake pedal depression amount signal obtained by a brake pedal sensor 2026, a shift lever operation signal obtained by a shift lever sensor 2027, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 2028.

[0178] The information service unit 2012 is composed of various devices, such as a car navigation system, an audio system, speakers, a television, and a radio, for providing (outputting) various types of information, such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 2012 uses information acquired from external devices via the communication module 2013 or the like to provide various types of multimedia information and multimedia services to the occupants of the vehicle 2001. The information service unit 2012 may include input devices (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, a touch panel, etc.) that accept input from the outside, and may also include output devices (e.g., a display, a speaker, an LED lamp, a touch panel, etc.) that output information to the outside.

[0179] The driving assistance system unit 2030 is composed of various devices that provide functions for preventing accidents and reducing the driving burden on the driver, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS, etc.), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. In addition, the driving assistance system unit 2030 transmits and receives various information via the communication module 2013 to realize the driving assistance function or the autonomous driving function.

[0180] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via the communication port. For example, the communication module 2013 transmits and receives data via the communication port 2033 to and from the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021 to 29, which are provided in the vehicle 2001.

[0181] The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station, a mobile station, or the like.

[0182] The communication module 2013 may transmit at least one of signals from the above-mentioned various sensors 2021-2028 input to the electronic control unit 2010, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 2012 to an external device via wireless communication. The electronic control unit 2010, the various sensors 2021-2028, the information service unit 2012, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above-mentioned input.

[0183] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle-to-vehicle information, etc.) transmitted from external devices and displays it on an information service unit 2012 provided in the vehicle 2001. The information service unit 2012 may be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH (or data / information decoded from the PDSCH) received by the communication module 2013). The communication module 2013 also stores the various information received from external devices in a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021 to 2029, etc. provided in the vehicle 2001.

[0184] (Summary of the embodiment) As described above, according to the embodiment of the present invention, there is provided a terminal including: a control unit that determines a channel access priority class (CAPC) to be applied to sidelink transmission including a physical sidelink feedback channel (PSFCH) and a sidelink synchronization signal / physical sidelink broadcast channel block (S-SSB) in an unlicensed band, and that performs a channel access procedure for performing the sidelink transmission; and a transmission unit that performs the sidelink transmission if the channel access procedure is successful.

[0185] The above configuration clarifies the UE operation when performing Type 1 LBT to transmit only PSFCH and S-SSB and acquiring COT, and enables the transmission of PSFCH and S-SSB. That is, in unlicensed bands, it is possible to determine the channel access priority class (CAPC) to be applied to LBT (Listen before talk).

[0186] The sidelink transmission may not include a PSCCH (Physical Sidelink Control Channel) or a PSSCH (Physical Sidelink Shared Channel). This configuration clarifies the UE behavior when performing Type 1 LBT to obtain COT for the transmission of only PSFCH and S-SSB, and enables the transmission of PSFCH and S-SSB.

[0187] The controller may determine the CAPC based on a fixed value. This configuration clarifies the UE operation when performing Type 1 LBT to obtain COT for transmitting only PSFCH and S-SSB, and enables transmission of PSFCH and S-SSB.

[0188] The controller may determine the CAPC based on a channel occupancy time (COT) size in which the sidelink transmission can be transmitted. This configuration clarifies the UE operation when performing Type 1 LBT to acquire COT for transmitting only the PSFCH and S-SSB, thereby enabling the transmission of the PSFCH and S-SSB.

[0189] The control unit may determine the CAPC based on a PSCCH (Physical Sidelink Control Channel) or a PSSCH (Physical Sidelink Shared Channel) corresponding to the PSFCH. This configuration clarifies UE operation when performing Type 1 LBT to acquire COT for transmitting only the PSFCH and S-SSB, and enables transmission of the PSFCH and S-SSB.

[0190] Furthermore, according to an embodiment of the present invention, there is provided a communication method in which a terminal determines a channel access priority class (CAPC) to be applied to sidelink transmission including a physical sidelink feedback channel (PSFCH) and a sidelink synchronization signal / physical sidelink broadcast channel block (S-SSB) in an unlicensed band, performs a channel access procedure for performing the sidelink transmission, and, if the channel access procedure is successful, performs the sidelink transmission.

[0191] The above configuration clarifies the UE operation when performing Type 1 LBT to transmit only PSFCH and S-SSB and acquiring COT, and enables the transmission of PSFCH and S-SSB. That is, in unlicensed bands, it is possible to determine the channel access priority class (CAPC) to be applied to LBT (Listen before talk).

[0192] (Supplementary Notes on the Embodiments) Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, and substitutions. While specific numerical examples have been used to facilitate understanding of the invention, unless otherwise specified, these numerical values ​​are merely examples, and any appropriate values ​​may be used. The division of items in the above description is not essential to the present invention; matters described in two or more items may be used in combination as needed, and matters described in one item may apply to matters described in another item (as long as there is no contradiction). Boundaries between functional units or processing units in functional block diagrams do not necessarily correspond to boundaries between physical components. The operations of multiple functional units may be performed by a single physical component, or the operations of a single functional unit may be performed by multiple physical components. The order of processing steps described in the embodiments may be reversed as long as there is no contradiction. For convenience of processing description, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be realized by hardware, software, or a combination thereof. The software operated by the processor of the base station 10 in accordance with an embodiment of the present invention and the software operated by the processor of the terminal 20 in accordance with an embodiment of the present invention may each be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.

[0193] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling), broadcast information (Master Information Block (MIB), System Information Block (SIB)), other signals, or a combination thereof. Furthermore, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0194] Each aspect / embodiment described in the present disclosure may be applied to at least one of systems using LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is, for example, an integer or a decimal)), FRA (Future Radio Access), NR (new Radio), New radio access (NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), and other suitable systems, as well as next-generation systems extended, modified, created, and defined based on these. Further, multiple systems may be combined (for example, a combination of at least one of LTE and LTE-A and 5G, etc.) and applied.

[0195] The processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this specification may be reordered as long as there is no contradiction. For example, for the methods described in the present disclosure, elements of various steps are presented using an exemplary order and are not limited to the specific order presented.

[0196] In this specification, a specific operation described as being performed by the base station 10 may be performed by its upper node in some cases. In a network consisting of one or more network nodes having the base station 10, it is clear that various operations performed for communication with the terminal 20 may be performed by at least one of the base station 10 and another network node other than the base station 10 (such as, but not limited to, an MME or an S-GW). Although the above example illustrates a case where there is one other network node other than the base station 10, the other network node may be a combination of multiple other network nodes (such as an MME and an S-GW).

[0197] The information, signals, etc. described in the present disclosure may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0198] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be transmitted to another device.

[0199] In the present disclosure, the determination may be made by a value represented by one bit (0 or 1), by a Boolean value (true or false), or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0200] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0201] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0202] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0203] Note that terms described in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0204] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0205] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0206] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0207] In the present disclosure, terms such as "base station (BS)," "radio base station," "base station," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. A base station may also be referred to by terms such as a macrocell, a small cell, a femtocell, and a picocell.

[0208] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be partitioned into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (e.g., a small indoor base station (RRH: Remote Radio Head)). The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication services within that coverage.

[0209] In the present disclosure, the base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control or operate based on the information.

[0210] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," and the like may be used interchangeably.

[0211] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0212] At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, the mobile object itself, etc. The mobile object refers to a movable object, and may move at any speed. Naturally, this also includes cases where the mobile object is stationary. Examples of the mobile object include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and objects mounted thereon. The mobile object may also be a mobile object that moves autonomously based on an operational command. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0213] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple terminals 20 (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0214] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station may be configured to have the functions of the user terminal described above.

[0215] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0216] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0217] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.

[0218] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0219] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0220] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0221] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0222] A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0223] Numerology may be communication parameters that apply to the transmission and / or reception of a signal or channel, such as subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by the transceiver in the frequency domain, specific windowing operations performed by the transceiver in the time domain, etc.

[0224] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol) in the time domain. A slot may be a time unit based on numerology.

[0225] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0226] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0227] For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc. instead of a subframe.

[0228] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate wireless resources (such as frequency bandwidth and transmission power that can be used by each terminal 20) to each terminal 20 in TTI units. Note that the definition of TTI is not limited to this.

[0229] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0230] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0231] A TTI having a time length of 1 ms may be called a regular TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0232] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and greater than or equal to 1 ms.

[0233] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of the numerology, for example, 12. The number of subcarriers included in an RB may be determined based on the numerology.

[0234] The time domain of an RB may include one or more symbols and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0235] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0236] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0237] A Bandwidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0238] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be set for the terminal 20 within one carrier.

[0239] At least one of the configured BWPs may be active, and the terminal 20 may not expect to transmit or receive a predetermined signal / channel outside the active BWP. Note that the terms "cell," "carrier," and the like in this disclosure may be read as "BWP."

[0240] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples, and various changes may be made to the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc.

[0241] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0242] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0243] The aspects / embodiments described in this disclosure may be used alone, in combination, or switched depending on the implementation. Notification of predetermined information (e.g., notification that "X is true") is not limited to explicit notification, but may be implicit (e.g., not notifying the predetermined information).

[0244] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

[0245] 10 Base station 110 Transmitter 120 Receiver 130 Setting unit 140 Control unit 20 Terminal 210 Transmitter 220 Receiver 230 Setting unit 240 Control unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device 2001 Vehicle 2002 Drive unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever 2007 Front wheels 2008 Rear wheels 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 Rotation speed sensor 2023 Tire pressure sensor 2024 Vehicle speed sensor 2025 Acceleration sensor 2026 Brake pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030 Driving assistance system unit 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port (IO port)

Claims

1. A terminal having a control unit that determines a channel access priority class (CAPC) to be applied to sidelink transmissions including a physical sidelink feedback channel (PSFCH) and a sidelink synchronization signal / physical sidelink broadcast channel block (S-SSB) in an unlicensed band and performs a channel access procedure to perform the sidelink transmissions, and a transmission unit that performs the sidelink transmissions if the channel access procedure is successful.

2. The terminal according to claim 1, wherein the sidelink transmission does not include a PSCCH (Physical Sidelink Control Channel) or a PSSCH (Physical Sidelink Shared Channel).

3. The terminal according to claim 1, wherein the control unit determines the CAPC based on a fixed value.

4. The terminal according to claim 1, wherein the control unit determines the CAPC based on a channel occupancy time (COT) size in which the sidelink transmission can be transmitted.

5. The terminal according to claim 1, wherein the control unit determines the CAPC based on a PSCCH (Physical Sidelink Control Channel) or a PSSCH (Physical Sidelink Shared Channel) corresponding to the PSFCH.

6. A communication method in which a terminal executes the following procedures: determining a channel access priority class (CAPC) to be applied to sidelink transmissions including a physical sidelink feedback channel (PSFCH) and a sidelink synchronization signal / physical sidelink broadcast channel block (S-SSB) in an unlicensed band; executing a channel access procedure to execute the sidelink transmissions; and executing the sidelink transmissions if the channel access procedure is successful.

Images