Terminal, communication method and communication system

Abstract

Provided is a terminal including: a reception unit that receives, in a resource pool in an unlicensed band, a signal from another terminal and performs sensing; a control unit that selects a resource to be used for transmission from the resource pool on the basis of the result of the sensing; and a transmission unit that transmits a signal to the other terminal in the selected resource. The control unit performs Listen before talk (LBT) for a given period in a symbol immediately before the selected resource or a symbol at the beginning of the selected resource.

Description

[Technical Field]

[0001] The present invention provides Terminal, communication method and communication system Regarding. [Background technology]

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

[0003] D2D reduces traffic between terminals and base stations and enables communication between terminals even when the base station becomes unavailable due to a disaster or other reason. Although 3GPP (3rd Generation Partnership Project) refers to D2D as a "sidelink," the more general term D2D is used in this specification. However, in the description of the embodiments described below, sidelink is also used as needed.

[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 will be simply referred to as D2D. Furthermore, signals transmitted and received in D2D will be referred to as D2D signals. Various use cases for services related to Vehicle to Everything (V2X) in NR are being studied (for example, Non-Patent Document 2).

[0005] In addition, NR Release 17 is considering using a higher frequency band than previous releases (e.g., Non-Patent Document 3). For example, in the frequency band from 52.6 GHz to 71 GHz, applicable numerology including subcarrier spacing and channel bandwidth, physical layer design, and expected interference in actual wireless communications are being considered. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] 3GPP TS 38.211 V16.6.0(2021-06) [Non-patent document 2] 3GPP TR 22.886 V15.1.0(2017-03) [Non-patent document 3] 3GPP TS 38.306 V16.5.0(2021-06) Summary of the Invention [Problem to be solved by the invention]

[0007] Newly operated frequency bands that use higher frequencies than conventional ones are designated as unlicensed bands. Various regulations are defined for unlicensed bands, such as the requirement to perform LBT (Listen Before Talk) when accessing a channel. When performing D2D communication in these high frequency bands, operation must comply with the regulations for unlicensed bands.

[0008] The present invention has been made in consideration of the above points, and aims to perform direct communication between terminals that satisfies regulations in unlicensed bands. [Means for solving the problem]

[0009] According to the disclosed technology, a control unit determines resources for transmitting a shared channel in a resource pool in a frequency band where LBT (Listen before talk) is performed in channel access, and uses the determined resources to: the shared channel to another terminal, wherein, if another transmission has been performed before the transmission on the determined resource, the control unit transmits the shared channel using at least a part of a period between the resource on which the other transmission was performed and the determined resource. [Effects of the Invention]

[0010] According to the disclosed technology, direct communication between terminals that meets regulations in unlicensed bands can be performed. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram for explaining V2X. [Figure 2] FIG. 4 is a diagram illustrating an example of a frequency range according to an embodiment of the present invention. [Figure 3] FIG. 10 is a diagram illustrating an example of resource allocation mode 1. [Figure 4] FIG. 1 is a diagram illustrating an example of a DCI format. [Figure 5] FIG. 10 is a diagram illustrating an example (1) of resource allocation mode 2. [Figure 6] FIG. 10 is a diagram illustrating an example (2) of resource allocation mode 2. [Figure 7] FIG. 1 illustrates an example of sidelink transmission. [Figure 8] FIG. 1 is a diagram illustrating an example (1) of sidelink transmission according to an embodiment of the present invention. [Figure 9] FIG. 10 is a diagram illustrating an example (2) of sidelink transmission according to an embodiment of the present invention. [Figure 10] FIG. 10 is a diagram illustrating an example of feedback channel transmission according to an embodiment of the present invention. [Figure 11] A diagram showing an example of a sidelink SSB. [Figure 12] FIG. 1 is a diagram showing an example (1) of an LBT according to an embodiment of the present invention. [Figure 13] FIG. 10 is a diagram illustrating an example (3) of sidelink transmission according to an embodiment of the present invention. [Figure 14] FIG. 10 is a diagram illustrating an example (4) of sidelink transmission according to an embodiment of the present invention. [Figure 15] FIG. 5 is a diagram showing an example (5) of sidelink transmission according to an embodiment of the present invention. [Figure 16] FIG. 10 is a diagram showing an example (1) of LBT when transmitting a feedback channel in an embodiment of the present invention. [Figure 17] FIG. 6 is a diagram illustrating an example (6) of sidelink transmission according to an embodiment of the present invention. [Figure 18] FIG. 10 is a diagram illustrating an example (2) of LBT when transmitting a feedback channel in an embodiment of the present invention. [Figure 19] 2 is a diagram illustrating an example of a functional configuration of a base station 10 according to an embodiment of the present invention. [Figure 20] FIG. 2 is a diagram illustrating an example of a functional configuration of a terminal 20 according to the embodiment of the present invention. [Figure 21] 2 is a diagram illustrating an example of a hardware configuration of a base station 10 or a terminal 20 according to an embodiment of the present invention. [Figure 22] FIG. 2 is a diagram showing an example of the configuration of a vehicle 2001 according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0012] 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.

[0013] In the operation of the wireless communication system according to the embodiment of the present invention, existing technologies are used as appropriate. However, the existing technologies are, for example, but not limited to, the existing LTE. Furthermore, the term "LTE" used in this specification has a broad meaning including LTE-Advanced, a system subsequent to LTE-Advanced (e.g., NR), or a wireless LAN (Local Area Network), unless otherwise specified.

[0014] Furthermore, in the embodiments of the present invention, the duplex method may be a TDD (Time Division Duplex) method, an FDD (Frequency Division Duplex) method, or other methods (for example, Flexible Duplex, etc.).

[0015] Furthermore, in the embodiments of the present invention, when radio parameters and the like are "configured," it may mean that predetermined values ​​are pre-configured, or that radio parameters notified from the base station 10 or the terminal 20 are set.

[0016] Figure 1 is a diagram for explaining V2X. 3GPP is studying the realization of V2X (Vehicle to Everything) or eV2X (enhanced V2X) by extending D2D functions, and is currently working on specifications. As shown in Figure 1, V2X is part of ITS (Intelligent Transport Systems) and is a collective term for V2V (Vehicle to Vehicle), which refers to a form of communication between vehicles; V2I (Vehicle to Infrastructure), which refers to a form of communication between vehicles and roadside units (RSUs) installed on the side of the road; V2N (Vehicle to Network), which refers to a form of communication between vehicles and ITS servers; and V2P (Vehicle to Pedestrian), which refers to a form of communication between vehicles and mobile terminals carried by pedestrians.

[0017] Additionally, 3GPP is studying V2X using LTE or NR cellular communications and device-to-device communications. V2X using cellular communications is also called cellular V2X. NR V2X is being studied to achieve high capacity, low latency, high reliability, and quality of service (QoS) control.

[0018] It is expected that future studies of LTE or NR V2X will be conducted beyond the 3GPP specifications, including ensuring interoperability, reducing costs through implementation of higher layers, using or switching between multiple RATs (Radio Access Technologies), complying with regulations in each country, and methods for acquiring, distributing, managing databases, and using data from LTE or NR V2X platforms.

[0019] 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.

[0020] 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) Time domain resource allocation 2) Frequency domain resource allocation 3) Reference synchronization signal (including SLSS (Sidelink Synchronization Signal)) 4) Reference signal used for path loss measurement for transmission power control

[0021] Furthermore, with regard to SL or UL Orthogonal Frequency Division Multiplexing (OFDM), any of CP-OFDM (Cyclic-Prefix OFDM), DFT-S-OFDM (Discrete Fourier Transform - Spread - OFDM), non-transform precoded OFDM, and transform precoded OFDM may be applied.

[0022] In the LTE SL, Mode 3 and Mode 4 are defined for SL resource allocation to terminal 20. In Mode 3, transmission resources are dynamically allocated by DCI (Downlink Control Information) transmitted from base station 10 to terminal 20. Also, in Mode 3, SPS (Semi Persistent Scheduling) is possible. In Mode 4, terminal 20 autonomously selects transmission resources from a resource pool.

[0023] 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). 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.

[0024] 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.

[0025] 3GPP Release 16 or Release 17 sidelink is specified for 1) and 2) below.

[0026] 1) An environment where only 3GPP terminals exist in the ITS (Intelligent Transport Systems) band 2) An environment in which UL resources can be used for SL in the licensed bands of FR1 (Frequency range 1) and FR2 defined in NR.

[0027] It is being considered to include unlicensed bands as sidelinks in 3GPP Release 18 and beyond, such as the 5 GHz-7 GHz band and the 60 GHz band.

[0028] FIG. 2 is a diagram illustrating an example of a frequency range in an embodiment of the present invention. The NR specifications of 3GPP Release 17 are considering operating a frequency band of, for example, 52.6 GHz or higher. As shown in FIG. 2, FR1, which is currently specified for operation, is a frequency band from 410 MHz to 7.125 GHz, with an SCS (Subcarrier Spacing) of 15, 30, or 60 kHz, and a bandwidth of 5 MHz to 100 MHz. FR2 is a frequency band from 24.25 GHz to 52.6 GHz, with an SCS of 60, 120, or 240 kHz, and a bandwidth of 50 MHz to 400 MHz. For example, a frequency band from 52.6 GHz to 71 GHz may be assumed to be newly operated.

[0029] 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.

[0030] 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.

[0031] In unlicensed bands, various regulations are established to prevent interference with other systems or other devices.

[0032] 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 transmission, and if the power exceeds a certain value, i.e., if transmission by another device is detected, the transmission is halted. A maximum channel occupancy time (MCOT) is also specified. MCOT is the maximum time period during which transmission is permitted if transmission is initiated after LBT; for example, it is 4 ms in Japan. The occupied channel bandwidth (OCB) requirement requires that transmissions using a certain carrier bandwidth must use at least X% of that bandwidth. For example, Europe requires the use of 80% to 100% of the nominal channel bandwidth (NCB). The OCB requirement aims to ensure that power detection during channel access is performed correctly. Regarding the maximum transmit power and maximum power spectral density, transmissions must be performed at or below a specified transmit power. For example, in Europe, the maximum transmission power is 23 dBm in the 5150 MHz-5350 MHz band. Also, for example, in Europe, the maximum power spectral density is 10 dBm / MHz in the 5150 MHz-5350 MHz band.

[0033] 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 by another device is detected, the transmission is stopped. It also specifies that transmissions are performed at or below a predetermined transmission power with respect to maximum transmission power and maximum power spectral density. It also specifies that the terminal must have the ability to satisfy OCB requirements.

[0034] In the sidelink in 3GPP Release 16 and Release 17, the following two resource allocation modes are defined:

[0035] 1) Resource Allocation Mode 1 The network schedules the sidelink, and the terminal 20 performs sidelink transmission based on the sidelink grant received from the network.

[0036] 2) Resource Allocation Mode 2 Terminal 20 autonomously selects sidelink resources for transmission. It monitors transmissions of other terminals 20 in advance and selects available resources. Monitoring transmissions of other terminals 20 may be called sensing. Each terminal 20 specifies future resources in transmission, which are referenced when selecting the above resources. Specifying future resources may be called reservation.

[0037] Fig. 3 is a diagram showing an example of resource allocation mode 1. As shown in Fig. 3, in resource allocation mode 1, SL transmission resources are allocated from base station 10 to terminal 20A. That is, as shown in Fig. 3, SL transmission resources (PSCCH / PSCCH) are allocated to terminal 20A by the PDCCH (specifically, DCI) received from base station 10, and terminal 20A performs SL transmission to terminal 20B using these transmission resources.

[0038] More specifically, the allocation of SL transmission from the base station 10 to the terminal 20A includes a dynamic grant (DG), a configured grant (CG) type 1, and a CG type 2. In resource allocation mode 1, DCI format 3_0 is used for DG and CG type 2. Note that the monitoring opportunity for DCI format 3_0 is set separately from the other formats.

[0039] Fig. 4 is a diagram illustrating an example of a DCI format. As shown in Fig. 4, information notified by DCI format 3_0 includes information on resources to be scheduled, information on initial transmission / retransmission, and information on HARQ (Hybrid automatic repeat request) feedback. Regarding the information on initial transmission / retransmission, transmitting terminal 20A manages the association between the HPN (HARQ Process Number) specified in DCI format 3_0 and the HPN in the SCI.

[0040] In resource allocation mode 2, a terminal 20 performs the following two steps to autonomously select resources for periodic or aperiodic traffic, taking into account periodic or aperiodic resource reservations of other terminals 20.

[0041] Step 1) Identify candidate resources in the resource selection window Step 2) From the identified candidates, select a resource to use for transmission or retransmission.

[0042] Step 1 above is performed based on two types of resource reservations: the first is a reservation for the transmission or retransmission of aperiodic traffic via the time resource assignment field, and the second is a reservation for the transmission or retransmission of periodic traffic via the resource reservation period field.

[0043] Figure 5 shows an example (1) of resource allocation mode 2. As shown in Figure 5, multiple resource reservations may be made in a single transmission. For example, the offset from the reserving transmission to the reserved resources may be from 1 slot to 31 slots.

[0044] Figure 6 is a diagram showing an example (2) of resource allocation mode 2. As shown in Figure 6, resources may be reserved periodically for a single transmission. The period may be, for example, 0 ms, 1 ms to 99 ms, 100 ms, 200 ms, 300 ms, 400 ms, 500 ms, 600 ms, 700 ms, 800 ms, 900 ms, or 1000 ms.

[0045] Here, it is necessary to specify operations related to sidelink (hereinafter also referred to as "SL-U") transmission in unlicensed bands. For example, it is necessary to specify operations corresponding to OCB requirements. For example, as a channel access operation, it is necessary to specify resource allocation mode 2, i.e., operations in which the terminal 20 autonomously selects sidelink resources. Also, for example, as a channel access operation, it is necessary to specify resource allocation mode 1, i.e., operations in which the network schedules the sidelink. Also, for example, as a channel access operation, it is necessary to specify a PSFCH (Physical Sidelink Feedback Channel) transmission operation after receiving a PSSCH (Physical Sidelink Shared Channel).

[0046] Therefore, operations related to sidelink transmission and reception in unlicensed bands may be specified. For example, operations corresponding to OCB requirements may be specified. For example, resource allocation mode 2, i.e., operations in which the terminal 20 autonomously selects sidelink resources, may be specified as channel access operations. For example, resource allocation mode 1, i.e., operations in which the network schedules the sidelink, may be specified as channel access operations. For example, PSFCH transmission operations after PSSCH reception may be specified as channel access operations.

[0047] Fig. 7 is a diagram illustrating an example of sidelink transmission. As shown in Fig. 7, in a conventional sidelink, the unit of frequency domain for transmission (hereinafter also referred to as "TX") is a subchannel. A subchannel is set by the number of PRBs (Physical Resource Blocks), and for example, a subchannel may be configured with 10, 12, 15, 20, 25, 50, 75, or 100 PRBs.

[0048] Fig. 8 illustrates an example (1) of sidelink transmission according to an embodiment of the present invention. As shown in Fig. 8, in order to comply with OCB requirements, interlacing may be applied to subchannels in a resource pool in an unlicensed band. The example in Fig. 8 illustrates an example in which interlacing is applied to subchannels #1 to #4. Each PSCCH / PSSCH transmission may be transmitted using an interlaced subchannel. Interlacing may be performed in units of one PRB, in units of multiple PRBs, or in units of multiple subcarriers.

[0049] The interlace structure may be realized by mapping VRBs (Virtual Resource Blocks) to PRBs (Physical Resource Blocks). An upper limit may be set for the number of subchannels, or an upper limit may be set for the interlace interval. A different value may be set for each SCS. For example, the upper limit for the interlace interval may be 10 PRBs for a 15 kHz SCS and 5 PRBs for a 30 kHz SCS.

[0050] By applying interlacing to subchannels as described above, it is possible to maintain the sidelink structure of subchannel-based reservation or transmission while satisfying the OCB requirements.

[0051] In an unlicensed band, a minimum number of subchannels to be used may be defined, and subchannels equal to or greater than the defined number may be used in each transmission. Fig. 9 is a diagram illustrating an example (2) of sidelink transmission according to an embodiment of the present invention. Fig. 9 illustrates an example in which the minimum number of subchannels to be used is two. [A] in Fig. 9 illustrates an example in which transmission using one subchannel is not permitted, i.e., transmission using two or more subchannels is permitted. [B] in Fig. 9 illustrates combinations of usable subchannels, and the minimum number of subchannels to be used may be a value satisfied for each combination. Additionally or alternatively, combinations of subchannels usable for a certain transmission may be defined, or combinations of subchannels that cannot be used may be defined.

[0052] Additionally or alternatively, one or more unused frequency resources (PRBs) may be defined between subchannels, as shown in [C] of Fig. 9. A resource pool may be defined as non-contiguous frequency resources. [C] of Fig. 9 shows an example in which transmission across one or more unused frequency resources between subchannels is not permitted. Resource allocation may be performed so as not to cross one or more unused frequency resources between subchannels.

[0053] The carrier bandwidth of the regulation (i.e., the LBT bandwidth) may differ from the carrier bandwidth of the 3GPP specification. One or more unused frequency resources between subchannels, such as [C] in Figure 9, may be used as a guard band between carrier bands in the regulation.

[0054] By defining the resource pool as described above, the OCB requirements can be satisfied and a wide bandwidth can be treated as one resource pool, thereby improving resource utilization efficiency.

[0055] Fig. 10 is a diagram illustrating an example of feedback channel transmission according to an embodiment of the present invention. In an unlicensed band, as shown in Fig. 10, a PSFCH resource may be defined as a channel to which interlacing is applied. Interlacing may be applied to a PSFCH resource at the same time that interlacing is applied to subchannels in a resource pool. Interlacing may be performed in units of one PRB, in units of multiple PRBs, or in units of multiple subcarriers.

[0056] Note that interlacing of PSFCH resources may mean, for example, that the same PSFCH resource is repeated and multiplexed in the frequency domain, or that one PSFCH resource is divided into multiple resources and multiplexed in the frequency domain.

[0057] An upper limit may be set for the number of frequency multiplexed PSFCHs, or for the number of PRBs in one PSFCH resource set shown in FIG. 10, or for the interlace spacing. A different value may be set for each SCS. For example, the upper limit of the interlace spacing may be 10 PRBs for a 15 kHz SCS or 5 PRBs for a 30 kHz SCS. In transmitting an interlaced PSFCH, the cyclic shift applied to the base sequence may differ for each frequency resource (e.g., for each PRB). For example, the index of the cyclic shift may be incremented by K, or K may be 5.

[0058] By applying interlacing to the PSFCH resources as described above, it is possible to achieve a configuration that satisfies the OCB requirements for PSFCH transmission as well.

[0059] Alternatively, the PSFCH resource may be defined as a channel of multiple RBs, which may be multiple consecutive RBs. PSFCH transmission of multiple RBs may be performed at the same time as interlacing of subchannels in a resource pool.

[0060] The number of RBs may be defined in the specifications, may be given in the configuration, or may be set in advance. It may be that the number of RBs used is equal to or greater than the number that satisfies the OCB requirement. When the number of RBs is N, the PSFCH resource is R PRB,cs PSFCH =N type PSFCH ×M subch,slot PSFCH ×N cs PSFCH ×N is defined as {(P ID +M ID ) mod R PRB,cs PSFCH}+n may be used, where n may be an integer from 0 to N-1. Other parameters may be the same as those for the sidelink in 3GPP Release 16 and Release 17.

[0061] Fig. 11 is a diagram showing an example of a sidelink SSB. As shown in Fig. 11, a sidelink SS / PBCH block (S-SSB) in 3GPP Release 16 and Release 17 may be composed of a sidelink primary SS (S-PSS) and a sidelink secondary SS (S-SSS) of 127 REs (Resource Elements), and a physical sidelink broadcast channel (PSBCH) of 11 RBs. Three demodulation reference signals (DM-RS) may be allocated to one RB in the PSBCH. The last symbol of the S-SSB may be empty to allow for switching between transmission and reception.

[0062] The amount of frequency resources for S-SSB in the unlicensed band may be different from that in the conventional ITS band or the licensed band.

[0063] For example, sequences longer than 127RE may be used for the S-PSS and S-SSS sequences. For example, they may be the same sequence as the PRACH preamble, a 1151 ZC (Zadoff-Chu) sequence, or a 571 ZC sequence for, for example, a 30 kHz SCS. For example, they may be a 1151 ZC sequence for, for example, a 15 kHz SCS, or a 571 ZC sequence for, for example, a 30 kHz SCS. The type of sequence, for example, an M sequence for S-PSS or a Gold sequence for S-SSS, may be the same, or only the sequence length may be changed. The same sequence may be repeated in the frequency direction, or a cyclic shift may be applied to all or part of it.

[0064] For example, the amount of PSBCH resources may be greater than 11 RBs. After generating a PSBCH with 11 RBs, the same code bits may be replicated in the frequency direction, or rate matching may be performed for all RBs used. The frequency spacing of the DM-RS for the PSBCH may be changed. The DM-RS sequence for the PSBCH may be replicated in the frequency direction after generating a PSBCH with 11 RBs, or may be generated based on all RBs used.

[0065] By configuring S-SSB as described above, it is possible to satisfy the OCB requirements, reduce the PAPR (Peak to Average Power Ratio), and improve the detection accuracy of S-SSB.

[0066] In unlicensed bands, PSCCH and / or PSSCH and / or CSI-RS may be transmitted simultaneously in the same time resource as S-SSB. S-SSB may be transmitted in a slot included in a resource pool, or S-SSB slots may not be excluded when determining the resource pool. Hereinafter, "PSCCH and / or PSSCH and / or CSI-RS" may also be referred to as "PSCCH / PSSCH / CSI-RS."

[0067] The S-SSB and the PSCCH / PSSCH / CSI-RS may be transmitted by frequency multiplexing. The PSCCH / PSSCH / CSI-RS may be transmitted in a configuration in a slot where there is no PSFCH resource. The PSCCH / PSSCH / CSI-RS may not be transmitted or received in a subchannel including the S-SSB.

[0068] Information regarding the time resource, frequency resource, and antenna port of the CSI-RS may be defined in a specification, may be provided in a configuration, or may be set in advance.

[0069] By configuring S-SSB as described above, it is possible to satisfy the OCB requirements, eliminating the need to change the S-SSB configuration from the conventional configuration, and simplifying the UE configuration for S-SSB transmission and reception.

[0070] In unlicensed bands, PSFCH and / or S-SSB transmission may not be allowed, which simplifies UE configuration by eliminating the need to modify PSFCH and / or S-SSB transmission to meet OCB requirements.

[0071] As a channel access operation in an unlicensed band, resource allocation mode 2, i.e., an operation in which the terminal 20 autonomously selects sidelink resources, may be defined as follows.

[0072] Fig. 12 is a diagram showing an example (1) of LBT according to an embodiment of the present invention. As shown in Fig. 12, terminal 20 may perform LBT before transmitting a certain PSCCH / PSSCH. As shown in [A] of Fig. 12, LBT may be performed in the last x μs period of the symbol immediately before the PSCCH / PSSCH resource (including a data-copied symbol) to be transmitted. If all symbols in a slot can be used for the sidelink, LBT may be performed in the x μs period immediately before the first symbol of the slot.

[0073] 12B, LBT may be performed during the first x μs of the first symbol of the PSCCH / PSSCH resource (data copy symbol) to be transmitted. When transmitting the PSCCH / PSSCH, terminal 20 does not need to transmit during the first x μs of the PSCCH / PSSCH symbol.

[0074] x may be a fixed value, defined by specifications, given in settings, or preset. x may be a random value satisfying x1<=x<=x2, and x1 and / or x2 may be fixed values, defined by specifications, given in settings, or preset.

[0075] As described above, by performing LBT when transmitting PSCCH / PSSCH, it is possible to detect signal transmissions from other systems in unlicensed bands.

[0076] After the LBT is successful, the terminal 20 may transmit the PSCCH / PSSCH. If no power exceeding a predetermined power value is detected in the LBT (defined as "LBT success"), the terminal 20 may be able to transmit the PSCCH / PSSCH in the corresponding slot.

[0077] When a resource pool spans multiple LBT bands, PSCCH / PSSCH transmission may be permitted only if LBT is successful in all of the multiple LBT bands, or PSCCH / PSSCH transmission may be permitted in the bands where LBT is successful among the multiple LBT bands.

[0078] Furthermore, if a resource pool spans multiple LBT bands, if LBT is successful in only some of the multiple LBT bands, all transmissions may be stopped, or PSCCH / PSSCH transmission may be allowed in subchannels in the bands where LBT was successful among the multiple LBT bands.

[0079] If terminal 20 detects power exceeding a predetermined power value in the LBT (defined as an "LBT failure"), it may not be permitted to transmit the PSCCH / PSSCH in the corresponding slot.

[0080] By performing LBT when transmitting PSCCH / PSSCH as described above, sidelink transmission can be performed so as to satisfy the channel access requirements.

[0081] When terminal 20 performs another transmission before a certain PSCCH / PSSCH transmission, terminal 20 may apply LBT based on the gap between the two transmissions. The other transmission may be any of PSCCH, PSSCH, PSFCH, or S-SSB.

[0082] If the gap is equal to or less than a predetermined value y, transmission may be performed without LBT (similar to Type 2c UL channel access). y may be a fixed value, may be defined in a specification, may be given by configuration, or may be set in advance. The length of the PSCCH / PSSCH transmission may be limited to a predetermined value (e.g., 584 μs).

[0083] Different LBT operations may be performed when the gap is equal to or smaller than a predetermined value z and when it exceeds z. z may be a fixed value, may be defined in the specifications, may be given by configuration, or may be set in advance. When the gap is equal to or smaller than z, the LBT may be performed as described above in FIG. 12. When the gap exceeds z, the LBT described above in FIG. 12 may be performed using a random value x where x1<=x<=x2 is satisfied for x in the LBT described above in FIG. 12.

[0084] The operation related to LBT may be determined based on the type of the other transmission. For example, if the other transmission is a PSCCH / PSSCH transmission, LBT may be performed, and if the other transmission is a PSFCH, LBT may not be performed.

[0085] By performing LBT based on the gap between transmissions as described above, it is possible to reduce the operations required for transmission based on regulations that allow transmission with simple LBT.

[0086] 13 is a diagram illustrating an example (3) of sidelink transmission according to an embodiment of the present invention. As shown in FIG. 13, if another transmission is performed before a certain PSCCH / PSSCH transmission, an additional predetermined transmission may be performed in the period between the two transmissions. The other transmission may be any of a PSCCH, a PSSCH, a PSFCH, or an S-SSB. The gap between the certain PSCCH / PSSCH transmission and the other transmission may be within a predetermined period.

[0087] The resource on which the specified transmission is performed may be any of 1)-4) shown below.

[0088] 1) at least a portion of the other transmitted symbols; 2) At least a portion of the symbols before transmission of the PSCCH / PSSCH 3) The time position and length of transmission may be defined by specifications, may be given by configuration, may be preset, or may vary depending on the SCS. 4) The frequency resource may be the same as that of the other transmission, may be the same as that of the PSCCH / PSSCH, or may be different from that of the other transmission and that of the PSCCH / PSSCH.

[0089] The predetermined transmission signal may be any of the following 1)-4).

[0090] 1) A signal defined for the function that performs the specified transmission, for example, a specified sequence signal (an M sequence that is a low PAPR sequence, a Gold sequence that is a pseudorandom sequence, a ZC sequence that is a low PAPR sequence, etc.) 2) The same signal as the other transmission 3) The same signal as the PSCCH / PSSCH transmission 4) Any signal

[0091] The transmission power of the predetermined transmission may be any of 1) to 3) shown below.

[0092] 1) The same transmission power as the other transmission 2) The same transmission power as that of the PSCCH / PSSCH 3) Predetermined value

[0093] The predetermined transmission may be subjected to the LBT based on the gap between transmissions described above, and if the continuous transmission exceeds a predetermined time, the predetermined transmission may not be performed.

[0094] As described above, by executing a predetermined transmission between two transmissions, it becomes possible to operate the transmissions as if they were continuous, thereby reducing the number of cases where LBT is required.

[0095] If terminal 20 performs other reception before transmitting a certain PSCCH / PSSCH and can detect a signal (e.g., a PSCCH) of another terminal 20 by a predetermined timing (e.g., successful decoding, i.e., passing a CRC check), terminal 20 may apply LBT based on the gap between the end of the reception and the start of the transmission. The other reception may be any of PSCCH, PSSCH, PSFCH, or S-SSB.

[0096] If the gap is equal to or less than a predetermined value y, transmission may be performed without LBT (similar to Type 2c UL channel access). y may be a fixed value, may be defined in a specification, may be given by configuration, or may be set in advance. The length of the PSCCH / PSSCH transmission may be limited to a predetermined value (e.g., 584 μs).

[0097] Different LBT operations may be performed when the gap is equal to or smaller than a predetermined value z and when it exceeds z. z may be a fixed value, may be defined in the specifications, may be given by configuration, or may be set in advance. When the gap is equal to or smaller than z, the LBT may be performed as described above in FIG. 12. When the gap exceeds z, the LBT described above in FIG. 12 may be performed using a random value x where x1<=x<=x2 is satisfied for x in the LBT described above in FIG. 12.

[0098] The operation related to LBT may be determined based on the type of the other transmission. For example, if the other transmission is a PSCCH / PSSCH transmission, LBT may be performed, and if the other transmission is a PSFCH, LBT may not be performed.

[0099] Fig. 14 is a diagram showing an example (4) of sidelink transmission according to an embodiment of the present invention. As shown in Fig. 14, if terminal 20 is performing other reception before transmitting a certain PSCCH / PSSCH and has detected a signal (e.g., a PSCCH) from another terminal 20 by a predetermined timing (e.g., successful decoding, i.e., passing a CRC check), terminal 20 may perform a predetermined transmission in the period from the end of the reception to the start of the transmission. The other reception may be any of a PSCCH, a PSSCH, a PSFCH, or an S-SSB.

[0100] The resource on which the specified transmission is performed may be any of 1)-4) shown below.

[0101] 1) at least a portion of the other received symbols; 2) At least a portion of the symbols before transmission of the PSCCH / PSSCH 3) The time position and length of transmission may be defined by specifications, may be given by configuration, may be preset, or may vary depending on the SCS. 4) The frequency resource may be the same as that of the other reception, may be the same as that of the PSCCH / PSSCH, or may be different from that of the other reception and that of the PSCCH / PSSCH.

[0102] The predetermined transmission signal may be any of the following 1)-4).

[0103] 1) A signal defined for the function that performs the specified transmission, for example, a specified sequence signal (an M sequence that is a low PAPR sequence, a Gold sequence that is a pseudorandom sequence, a ZC sequence that is a low PAPR sequence, etc.) 2) The same signal as the other reception 3) The same signal as the PSCCH / PSSCH transmission 4) Any signal

[0104] The transmission power of the predetermined transmission may be any of 1) to 3) shown below.

[0105] 1) The same transmission power as the other reception 2) The same transmission power as that of the PSCCH / PSSCH 3) Predetermined value

[0106] The predetermined transmission may be subjected to the LBT based on the gap between transmission and reception as described above. If the continuous transmission exceeds a predetermined time, the predetermined transmission may not be performed.

[0107] The operations during transmission of a certain PSCCH / PSSCH in resource allocation mode 2 described above may be similarly applied to operations before transmission of an S-SSB.

[0108] Note that S-SSB transmission may not be performed in unlicensed bands. For example, terminal 20 may establish synchronization based on a signal received from a Global Navigation Satellite System (GNSS), an eNB, or a gNB. For example, terminal 20 may not perform S-SSB reception operations. This can avoid an increase in LBT operations. Furthermore, LBT may be performed before PSCCH transmission and may not be associated with PSSCH transmission.

[0109] Note that the above-described operation before transmission of a certain PSCCH / PSSCH in resource allocation mode 2 may be applied in combination with any of the operations corresponding to the above-described OCB requirements, such as the configuration of a resource pool.

[0110] As a channel access operation in an unlicensed band, resource allocation mode 1, i.e., the operation when the network schedules sidelink resources, may be defined as follows:

[0111] After receiving the sidelink dynamic grant from the network, the terminal 20 may perform the LBT operations related to the sidelink transmission shown in 1)-3) below.

[0112] 1) Based on the regulations, LBT may be performed before transmitting the PSCCH / PSSCH. This may be a method similar to any of the LBT operations in resource allocation mode 2 described above, or may be the same as the LBT operation in resource allocation mode 2 described above.

[0113] 2) Based on a notification regarding LBT received from the network, LBT may be performed before transmitting the PSCCH / PSSCH. It may be configured or instructed to perform any of the LBT operations in resource allocation mode 2 described above. It may also be configured or instructed to transmit without power detection. If a signal from another terminal 20 cannot be detected in the resources immediately before transmission (e.g., due to decoding failure or CRC check error), an LBT method different from the configured or instructed LBT may be applied.

[0114] 3) Depending on whether the assigned sidelink resources are contiguous in the time direction, a method of LBT to be performed before transmitting the PSCCH / PSSCH may be determined and performed. The corresponding PSFCH may be included in the assigned sidelink resources.

[0115] As described above, by performing the LBT operation in resource allocation mode 1, it is possible to perform LBT based on the sidelink scheduling of the network. In addition, by performing LBT based on the transmission status of all sidelink terminals, it is possible to avoid unnecessary LBT.

[0116] After configuring or activating a sidelink configured grant (CG) received from the network, the terminal 20 may perform the LBT operations related to sidelink transmissions shown in 1)-4) below.

[0117] 1) Based on the regulations, LBT may be performed before transmitting the PSCCH / PSSCH. This may be a method similar to any of the LBT operations in resource allocation mode 2 described above, or may be the same as the LBT operation in resource allocation mode 2 described above.

[0118] 2) Based on a notification related to LBT received from the network, LBT may be performed before transmitting the PSCCH / PSSCH. It may be configured or instructed to perform any of the LBT operations in resource allocation mode 2 described above. It may also be configured or instructed to transmit without power detection. If a signal from another terminal 20 cannot be detected in the resources immediately before transmission (e.g., due to a decoding failure or a CRC check error), an LBT method different from the configured or instructed LBT may be applied. The LBT method may be specified in the CG configuration, or in the activation command.

[0119] 3) The method of LBT to be performed before the transmission of PSCCH / PSSCH may be determined and executed based on whether the allocated sidelink resources are contiguous in the time direction. The corresponding PSFCH may be included in the allocated sidelink resources. The above "contiguous in the time direction" may be a condition for resources in a certain CG period or a condition for resources in adjacent CG periods.

[0120] 4) A transport block may be transmitted across a CG cycle. For example, the same transport block may be transmitted in slot n and slot n+P for CG resources of slot n, slot n+P, slot n+2P, slot n+3P, etc. Whether or not it is the same transport block may be indicated in the first stage SCI via the PSCCH, or in the second stage SCI via the PSCCH.

[0121] As described above, by performing LBT operations in the CG in resource allocation mode 1, LBT can be performed based on the sidelink scheduling of the network. Furthermore, by performing LBT based on the transmission status of all sidelink terminals, unnecessary LBT can be avoided, allowing for efficient use of CG resources.

[0122] After the LBT is successful, the terminal 20 may transmit the PSCCH / PSSCH. If no power exceeding a predetermined power value is detected in the LBT (defined as "LBT success"), the terminal 20 may be able to transmit the PSCCH / PSSCH in the corresponding slot.

[0123] When a resource pool spans multiple LBT bands, PSCCH / PSSCH transmission may be permitted only if LBT is successful in all of the multiple LBT bands, or PSCCH / PSSCH transmission may be permitted in the bands where LBT is successful among the multiple LBT bands.

[0124] Furthermore, if a resource pool spans multiple LBT bands, if LBT is successful in only some of the multiple LBT bands, all transmissions may be stopped, or PSCCH / PSSCH transmission may be allowed in subchannels in the bands where LBT was successful among the multiple LBT bands.

[0125] If terminal 20 detects power exceeding a predetermined power value in the LBT (defined as an "LBT failure"), it may not be permitted to transmit the PSCCH / PSSCH in the corresponding slot.

[0126] As described above, by performing LBT when transmitting PSCCH / PSSCH in resource allocation mode 1, sidelink transmission can be performed so as to satisfy the channel access requirements.

[0127] FIG. 15 is a diagram illustrating an example (5) of sidelink transmission according to an embodiment of the present invention. As shown in FIG. 15, a predetermined transmission may be configured or signaled to occur in a predetermined time resource before the resource for transmitting the PSCCH / PSSCH allocated to the network.

[0128] The resource on which the predetermined transmission is performed may be any of the following 1) to 3). Information related to any of the transmission operations on the resource may be notified to the terminal 20 from the network.

[0129] 1) At least a portion of the symbols before transmission of the PSCCH / PSSCH 2) The time position and length of transmission may be defined by specifications, may be given by configuration, may be preset, or may vary depending on the SCS. 3) The frequency resource may be the same as the PSCCH / PSSCH, or may be different from the other transmissions and the PSCCH / PSSCH.

[0130] The predetermined transmission signal may be any of the following 1) to 3). Information related to any of the predetermined transmission operations may be notified to the terminal 20 from the network.

[0131] 1) A signal defined for the function that performs the specified transmission, for example, a specified sequence signal (an M sequence that is a low PAPR sequence, a Gold sequence that is a pseudorandom sequence, a ZC sequence that is a low PAPR sequence, etc.) 2) The same signal as the PSCCH / PSSCH transmission 3) Any signal

[0132] The transmission power of the predetermined transmission may be any of the following 1) to 3). Information relating to any of the transmission power of the predetermined transmission may be notified to the terminal 20 from the network.

[0133] 1) The same transmission power as that of the PSCCH / PSSCH 2) Predetermined value

[0134] Terminal 20 may perform the predetermined transmission based on the above information before the PSCCH / PSSCH transmission resources allocated by the network. Before performing the predetermined transmission, LBT may not be performed, or a predetermined LBT (for example, any of the LBT methods in resource allocation mode 2 described above) may be performed.

[0135] The predetermined transmission may be subjected to the LBT based on the gap between transmissions described above, and if the continuous transmission exceeds a predetermined time, the predetermined transmission may not be performed.

[0136] As described above, by executing a predetermined transmission between two transmissions, the network can control the transmissions to be continuous, thereby reducing the number of cases where LBT is required.

[0137] When reporting a sidelink HARQ-ACK report to the network via the PUCCH, the terminal 20 may perform the following operations 1)-2).

[0138] 1) If all or part of a transmission on a sidelink resource according to a scheduled dynamic grant or CG cannot be performed due to an LBT failure and if a PUCCH resource corresponding to the transmission exists, a NACK is transmitted on the PUCCH or PUSCH. The priority of the NACK may be the same as that of the data that could not be transmitted due to an LBT failure. Instead of a NACK, information indicating that the transmission could not be performed due to an LBT failure may be transmitted.

[0139] 2) For resource allocation mode 1 in unlicensed bands, terminal 20 may assume that it is given PUCCH resources corresponding to sidelink resources, e.g., it may not assume a sidelink grant without PUCCH resources.

[0140] As described above, by reporting a sidelink HARQ-ACK to the network, retransmission resources can be requested when an LBT fails.

[0141] The terminal 20 may report information related to the channel state of the sidelink to the network as shown in 1)-4) below.

[0142] 1) The terminal 20 may report information related to LBT success or failure to the network. The terminal 20 may report the number of LBT successes or LBT failures in a predetermined time period to the network. The terminal 20 may also report the probability of LBT success or LBT failure to the network.

[0143] 2) The terminal 20 may report information on the detected power value in the LBT period to the network. The detected power value may be an average value in a predetermined time period.

[0144] 3) The reporting of information related to the channel state of the sidelink may be performed on either the PUCCH or the PUSCH, and may be performed on any of the PHY, MAC, and RRC layers.

[0145] 4) The reporting of information related to the channel state of the sidelink and / or the content of the report may be configured or instructed by the network, or the terminal 20 may report autonomously.

[0146] As described above, by reporting information regarding the channel condition of the sidelink to the network, the network can know the channel condition of the sidelink.

[0147] The operations before network scheduled PSCCH / PSSCH transmission in resource allocation mode 1 described above may be similarly applied to the operations before S-SSB transmission.

[0148] Note that S-SSB transmission may not be performed in the unlicensed band. For example, the terminal 20 may establish synchronization based on a signal received from a GNSS, eNB, or gNB. For example, the terminal 20 may not perform S-SSB reception operations. This can avoid an increase in LBT operations. Furthermore, the LBT may be performed before the PSCCH transmission and may not be associated with the PSSCH transmission.

[0149] Note that the operation at the time of transmitting PSCCH / PSSCH scheduled by the network in the above-described resource allocation mode 1 may be applied in combination with any of the operations corresponding to the above-described OCB requirements, for example, any of the resource pool configurations.

[0150] As a channel access operation in an unlicensed band, the operation of transmitting a PSFCH after receiving a PSSCH may be specified as follows.

[0151] Fig. 16 is a diagram showing an example (1) of LBT when transmitting a feedback channel in an embodiment of the present invention. Terminal 20 may perform LBT before transmitting a PSFCH. For example, as shown in [A] of Fig. 16, LBT may be performed in the last p μs period of the symbol immediately before the PSFCH resource (including the data copy symbol) to be transmitted. When all symbols in a slot can be used for the sidelink, LBT may be performed in the p μs period immediately before the symbol two symbols before the last symbol of the slot.

[0152] Furthermore, as shown in [B] of Fig. 16, LBT may be performed during the first pµs of the first symbol of the PSFCH resource (data copy symbol) to be transmitted. When transmitting a PSFCH, terminal 20 does not need to perform transmission during the first pµs of the PSFCH symbol.

[0153] p may be a fixed value, may be defined in the specifications, may be given in the settings, or may be set in advance. p may be a random value satisfying p1<=p<=p2, and p1 and / or p2 may be fixed values, may be defined in the specifications, may be given in the settings, or may be set in advance.

[0154] As described above, by performing LBT when transmitting PSCCH / PSSCH, it is possible to detect signal transmissions from other systems in unlicensed bands.

[0155] After the LBT is successful, the terminal 20 may transmit the PSFCH. If no power exceeding a predetermined power value is detected in the LBT (defined as "LBT success"), the terminal 20 may be able to transmit the PSFCH in the corresponding slot.

[0156] When a resource pool spans multiple LBT bands, PSFCH transmission may be permitted only if LBT is successful in all of the multiple LBT bands, or PSFCH transmission may be permitted in a band among the multiple LBT bands in which LBT is successful.

[0157] Furthermore, if a resource pool spans multiple LBT bands, if LBT is successful in only some of the multiple LBT bands, all transmissions may be stopped, or PSFCH transmission may be allowed in a subchannel in one of the multiple LBT bands where LBT was successful.

[0158] If terminal 20 detects power exceeding a predetermined power value in the LBT (defined as an "LBT failure"), it may not be permitted to transmit the PSFCH in the corresponding slot.

[0159] By performing LBT when transmitting the PSFCH as described above, sidelink transmission can be performed so as to satisfy the channel access requirements.

[0160] When terminal 20 performs another transmission before a certain PSFCH transmission, terminal 20 may apply LBT based on the gap between the two transmissions. The other transmission may be any of a PSCCH, a PSSCH, a PSFCH, or an S-SSB.

[0161] If the gap is equal to or less than a predetermined value q, transmission may be performed without LBT (similar to Type 2cUL channel access). q may be a fixed value, may be defined in a specification, may be given by configuration, or may be set in advance. The length of the PSFCH transmission may be limited to a predetermined value.

[0162] Different LBT operations may be performed when the gap is equal to or less than a predetermined value r and when it exceeds r. r may be a fixed value, may be defined in the specifications, may be given by configuration, or may be set in advance. When the gap is equal to or less than r, the LBT described in FIG. 16 above, in which p is a fixed value, may be performed. When the gap exceeds r, the LBT described in FIG. 16 above, in which p is a random value p satisfying p1<=p<=p2 may be performed.

[0163] The operation related to LBT may be determined based on the type of the other transmission. For example, if the other transmission is a PSCCH / PSSCH transmission, LBT may be performed, and if the other transmission is a PSFCH, LBT may not be performed.

[0164] By performing LBT based on the gap between transmissions as described above, it is possible to reduce the operations required for transmission based on regulations that allow transmission with simple LBT.

[0165] 17 is a diagram illustrating an example (6) of sidelink transmission according to an embodiment of the present invention. As shown in FIG. 17, if another transmission is performed before a certain PSFCH transmission, an additional predetermined transmission may be performed in the period between the two transmissions. The other transmission may be any of a PSCCH, a PSSCH, a PSFCH, or an S-SSB.

[0166] The resource on which the specified transmission is performed may be any of 1)-4) shown below.

[0167] 1) at least a portion of the other transmitted symbols; 2) At least a portion of the symbols before transmission of the PSFCH 3) The time position and length of transmission may be defined by specifications, may be given by configuration, may be preset, or may vary depending on the SCS. 4) The frequency resources may be the same as those of the other transmission, may be the same as those of the PSFCH, or may be different from those of the other transmission and the PSFCH.

[0168] The predetermined transmission signal may be any of the following 1)-4).

[0169] 1) A signal defined for the function that performs the specified transmission, for example, a specified sequence signal (an M sequence that is a low PAPR sequence, a Gold sequence that is a pseudorandom sequence, a ZC sequence that is a low PAPR sequence, etc.) 2) The same signal as the other transmission 3) The same signal as that transmitted by the PSFCH 4) Any signal

[0170] The transmission power of the predetermined transmission may be any of 1) to 3) shown below.

[0171] 1) The same transmission power as the other transmission 2) The same transmission power as that of the PSFCH 3) Predetermined value

[0172] The predetermined transmission may be subjected to the LBT based on the gap between transmissions described above, and if the continuous transmission exceeds a predetermined time, the predetermined transmission may not be performed.

[0173] As described above, by executing a predetermined transmission between two transmissions, it becomes possible to operate the transmissions as if they were continuous, thereby reducing the number of cases where LBT is required.

[0174] If the terminal 20 is performing other reception before transmitting a certain PSFCH and can detect a signal (e.g., a PSCCH) of the other terminal 20 by a predetermined timing (e.g., successful decoding, i.e., passing a CRC check), the terminal 20 may apply LBT based on the gap between the end of the reception and the start of the transmission. The other reception may be any of a PSCCH, a PSSCH, a PSFCH, or an S-SSB.

[0175] If the gap is equal to or less than a predetermined value q, transmission may be performed without LBT (similar to Type 2cUL channel access). q may be a fixed value, may be defined in a specification, may be given by configuration, or may be set in advance. The length of the PSFCH transmission may be limited to a predetermined value.

[0176] Different LBT operations may be performed when the gap is equal to or less than a predetermined value r and when it exceeds r. r may be a fixed value, may be defined in the specifications, may be given by configuration, or may be set in advance. When the gap is equal to or less than r, the LBT described in FIG. 16 above, in which p is a fixed value, may be performed. When the gap exceeds r, the LBT described in FIG. 16 above, in which p is a random value p satisfying p1<=p<=p2 may be performed.

[0177] The operation related to LBT may be determined based on the type of the other reception. For example, if the other reception is a PSCCH / PSSCH reception, LBT may be performed, and if the other reception is a PSFCH, LBT may not be performed.

[0178] If terminal 20 is receiving another signal before transmitting a PSFCH, terminal 20 may perform an additional predetermined transmission during the period from the end of the reception to the start of the transmission. The other reception may be any of PSCCH, PSSCH, PSFCH, or S-SSB.

[0179] The resource on which the specified transmission is performed may be any of 1)-4) shown below.

[0180] 1) at least a portion of the other received symbols; 2) At least a portion of the symbols before transmission of the PSFCH 3) The time position and length of transmission may be defined by specifications, may be given by configuration, may be preset, or may vary depending on the SCS. 4) The frequency resource may be the same as that of the other reception, may be the same as that of the PSFCH, or may be different from that of the other reception and that of the PSFCH.

[0181] The predetermined transmission signal may be any of the following 1)-4).

[0182] 1) A signal defined for the function that performs the specified transmission, for example, a specified sequence signal (an M sequence that is a low PAPR sequence, a Gold sequence that is a pseudorandom sequence, a ZC sequence that is a low PAPR sequence, etc.) 2) The same signal as the other reception 3) The same signal as that transmitted by the PSFCH 4) Any signal

[0183] The transmission power of the predetermined transmission may be any of 1) to 3) shown below.

[0184] 1) The same transmission power as the other reception 2) The same transmission power as that of the PSFCH 3) Predetermined value

[0185] The predetermined transmission may be subjected to the LBT based on the gap between transmission and reception as described above. If the continuous transmission exceeds a predetermined time, the predetermined transmission may not be performed.

[0186] Terminal 20 may transmit the PSFCH without power detection or LBT after receiving the PSSCH. It may be assumed that terminal 20 transmitting the PSCCH / PSSCH corresponding to the PSFCH will transmit another PSCCH / PSSCH in the resource immediately before the PSFCH. The other PSCCH / PSSCH transmission may be transmission of the same transport block or may be transmission of a different transport block. The above-described operation makes it possible to skip the LBT that is not required for transmitting the PSFCH.

[0187] 18 is a diagram showing an example (2) of an LBT when transmitting a feedback channel according to an embodiment of the present invention. As shown in FIG. 18, based on a notification related to an LBT for PSFCH transmission received on a PSCCH / PSSCH corresponding to a PFSCH, an LBT may be performed before the transmission of the PSFCH.

[0188] The notification related to the LBT for PSFCH transmission may indicate which of the above-mentioned operations related to PSFCH transmission to apply. If a signal from another terminal 20 cannot be detected in the resource immediately before transmission (for example, decoding failure or CRC check error), or if a predetermined condition (for example, a condition in the above-mentioned operation related to PSFCH transmission) is satisfied, an LBT method different from the LBT instructed by the notification may be applied. The notification may be notified in the first stage SCI via the PSCCH, or may be notified in the second stage SCI via the PSCCH.

[0189] A terminal 20 transmitting a PSCCH / PSSCH corresponding to a PSFCH may notify a terminal 20 transmitting a PSFCH of information related to an LBT required for the PSFCH transmission. A terminal 20 transmitting a PSCCH / PSSCH may determine the information to be notified based on which of the conditions for the operation related to PSFCH transmission described above is satisfied in the terminal 20 transmitting the PSFCH. For example, when transmitting another PSCCH / PSSCH in the resources immediately before the PSFCH, a terminal 20 transmitting a PSCCH / PSSCH may notify a terminal 20 transmitting a PSFCH that it will transmit the PSFCH without an LBT.

[0190] By transmitting a PSFCH after receiving a PSSCH as described above, it is possible to execute an LBT without excess or deficiency based on information held by terminal 20 that transmits the corresponding PSCCH / PSSCH.

[0191] In the unlicensed band, terminal 20 may be subject to the following restrictions on PSFCH transmission requests 1)-4). Note that in groupcast option 1, only NACK is transmitted as the HARQ response, and ACK is not transmitted. In groupcast option 2, either ACK or NACK is transmitted as the HARQ response.

[0192] 1) Groupcast option 2 may be disabled. This avoids simultaneous transmission of PSFCH and can prevent cases where other systems are excessively affected.

[0193] 2) An upper limit may be set for the number of UEs that receive in groupcast option 2. By placing a restriction on the number of simultaneous transmissions of PSFCH, it is possible to avoid cases where other systems are excessively affected.

[0194] 3) Groupcast option 1 may be disabled to avoid excessive power consumption of certain resources.

[0195] 4) A plurality of resources may be associated as PSFCH resources for a PSCCH / PSSCH of a certain groupcast option 1. For example, the PSFCH resource ID may be given in the following manner.

[0196] (P ID +M ID ) mod R PRB,cs PSFCH P ID is the physical layer source ID given by the SCI that schedules the PSSCH. ID is an identifier notified by the upper layer of the UE receiving the PSSCH if the detected cast type indicator is "01", and may be 0 if not detected. PRB,cs PSFCH is the number of PSFCH resources available for HARQ-ACK multiplexing in PSFCH transmission.

[0197] For example, M ID The method for determining M may be as follows. For example, ID may be set or may be preset. For example, M ID may be randomly determined from a range of predetermined values. For example, M ID may be determined from a predetermined range of values ​​based on the identifier of the physical layer or upper layer of the device itself. ID may be determined in the same manner as if the cast type indicator was found to be "01".

[0198] By imposing restrictions on PSFCH transmission requests as described above, sidelink transmissions related to groupcast can be performed so as to satisfy the regulations for unlicensed bands.

[0199] Note that the above-described operation during PSFCH transmission may be applied in combination with any of the operations corresponding to the above-described OCB requirements, for example, the configuration of the resource pool.

[0200] The above-described embodiment may be applied to an operation in which one terminal 20 configures or allocates transmission resources for another terminal 20.

[0201] The above-described embodiment is not limited to V2X terminals, and may be applied to terminals that perform D2D communication.

[0202] According to the above-described embodiment, it is possible to configure a resource pool in an unlicensed band so as to satisfy regulations. Furthermore, in an unlicensed band, the terminal 20 can perform PSCCH / PSSCH transmission in resource allocation mode 2 so as to satisfy regulations. Furthermore, in an unlicensed band, the terminal 20 can perform PSCCH / PSSCH transmission in resource allocation mode 1 so as to satisfy regulations. Furthermore, in an unlicensed band, the terminal 20 can perform PSFCH transmission so as to satisfy regulations.

[0203] In other words, direct communication between terminals that satisfies the regulations in unlicensed bands can be performed.

[0204] (Device configuration) Next, a description will be given of an example of the functional configuration of the base station 10 and the terminal 20 that execute the processes and operations described above. 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.

[0205] <Base station 10> Fig. 19 is a diagram showing an example of the functional configuration of base station 10. As shown in Fig. 19, 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. 19 is merely an example. The names of the functional divisions and functional units may be any as long as they can perform the operations related to the embodiments of the present invention.

[0206] 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 signals. The transmitter 110 also has a function of transmitting an NR-PSS, an NR-SSS, an NR-PBCH, a DL / UL control signal, a DL reference signal, etc. to the terminal 20.

[0207] 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.

[0208] 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.

[0209] <Terminal 20> Fig. 20 is a diagram showing an example of the functional configuration of terminal 20. As shown in Fig. 20, 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. 20 is merely an example. The names of the functional divisions and functional units may be any names as long as they can execute the operations related to the embodiment of the present invention.

[0210] The transmitter 210 creates a transmission signal from transmission data and transmits the transmission signal wirelessly. The receiver 220 receives various signals wirelessly and acquires a higher layer signal from the received physical layer signal. The receiver 220 also has a function of receiving an NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signal, reference signal, or the like 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, or the like, from the other terminal 20.

[0211] The setting unit 230 stores various setting information received from the base station 10 or the terminal 20 by the receiving unit 220 in a storage device and reads it 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.

[0212] As described in the embodiments, the control unit 240 controls D2D communication for establishing 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 information related to HARQ responses for D2D communication and DL communication to another terminal 20 scheduled by the base station 10 to the base station 10. The control unit 240 may also schedule D2D communication for another terminal 20. The control unit 240 may also autonomously select resources to be used for D2D communication from a resource selection window based on a sensing result, or may perform re-evaluation 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. A functional unit related to signal transmission in the control unit 240 may be included in the transmission unit 210, and a functional unit related to signal reception in the control unit 240 may be included in the reception unit 220.

[0213] (Hardware configuration) The block diagrams (FIGS. 19 and 20) 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 connected directly or indirectly (for example, by wire, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining software with the single device or the multiple devices.

[0214] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocation, 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.

[0215] 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. 21 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.

[0216] In the following description, the term "apparatus" can be read 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.

[0217] Each function in the base station 10 and the terminal 20 is realized by loading predetermined 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.

[0218] 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.

[0219] 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. 19 may be implemented by a control program stored in the storage device 1002 and executed by the processor 1001. Furthermore, for example, the control unit 240 of the terminal 20 shown in FIG. 20 may be implemented by a control program stored in the storage device 1002 and executed by 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 be transmitted from a network via a telecommunications line.

[0220] 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 ROM (EPROM), an electrically erasable programmable ROM (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.

[0221] 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 disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. The above-mentioned storage medium may be, for example, a database, a server, or other suitable medium including at least one of the storage device 1002 and the secondary storage device 1003.

[0222] 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, or a communication module. 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.

[0223] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0224] 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.

[0225] Furthermore, base station 10 and 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, processor 1001 may be implemented using at least one of these pieces of hardware.

[0226] Fig. 22 shows an example configuration of a vehicle 2001. As shown in Fig. 22, 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.

[0227] 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.

[0228] 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).

[0229] 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.

[0230] 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 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 obtained from external devices via the communication module 2013, etc., to provide various types of multimedia information and multimedia services to the occupants of the vehicle 2001.

[0231] The driving assistance system unit 2030 is composed of various devices that provide functions for preventing accidents and reducing the driver's driving burden, such as a millimeter-wave radar, a LiDAR (Light Detection and Ranging), a camera, a positioning locator (e.g., GNSS, etc.), map information (e.g., high-definition (HD) map, autonomous vehicle (AV) map, etc.), a gyro system (e.g., an IMU (Inertial Measurement Unit), an INS (Inertial Navigation System), etc.), an AI (Artificial Intelligence) chip, and an AI processor, as well as one or more ECUs that control these devices. The driving assistance system unit 2030 also transmits and receives various information via the communication module 2013 to realize the driving assistance function or the autonomous driving function.

[0232] 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.

[0233] 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.

[0234] The communication module 2013 transmits, via wireless communication to an external device, a current signal from the current sensor that is input to the electronic control unit 2010. The communication module 2013 also transmits, via wireless communication to an external device, the rotation speed signals of the front and rear wheels acquired by a rotation speed sensor 2022, the air pressure signals of the front and rear wheels acquired by an air pressure sensor 2023, the vehicle speed signal acquired by a vehicle speed sensor 2024, the acceleration signal acquired by an acceleration sensor 2025, the accelerator pedal depression amount signal acquired by an accelerator pedal sensor 2029, the brake pedal depression amount signal acquired by a brake pedal sensor 2026, the shift lever operation signal acquired by a shift lever sensor 2027, and the detection signals for detecting obstacles, vehicles, pedestrians, etc. acquired by an object detection sensor 2028, which are input to the electronic control unit 2010.

[0235] The communication module 2013 receives various information (traffic information, traffic signal information, inter-vehicle information, etc.) transmitted from external devices and displays it on an information service unit 2012 provided in the vehicle 2001. The communication module 2013 also stores the various information received from the 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, axle 2009, sensors 2021 to 2029, etc. provided in the vehicle 2001.

[0236] (Summary of the embodiment) As described above, according to an embodiment of the present invention, a terminal is provided that has a receiving unit that receives signals from other terminals and performs sensing in a resource pool in an unlicensed band, a control unit that selects resources to be used for transmission from the resource pool based on the results of the sensing, and a transmitting unit that transmits signals to other terminals in the selected resources, wherein the control unit performs LBT (Listen before talk) for a certain period of time in the symbol immediately before the selected resource or the first symbol of the selected resource.

[0237] With the above configuration, in the unlicensed band, terminal 20 can perform PSCCH / PSSCH transmission in resource allocation mode 2 so as to satisfy regulations. In other words, it is possible to perform direct terminal-to-terminal communication that satisfies regulations in the unlicensed band.

[0238] The certain period may have a random length within a certain range. This configuration enables PSCCH / PSSCH transmission in resource allocation mode 2 in unlicensed bands.

[0239] In a case where another transmission has been performed before the transmission on the selected resource, and a gap between the other transmission and the transmission on the selected resource is less than a threshold, the controller may perform the transmission on the selected resource without performing LBT. With this configuration, PSCCH / PSSCH transmission in resource allocation mode 2 can be efficiently performed in an unlicensed band.

[0240] When another transmission has been performed before the transmission on the selected resource, the controller may perform the transmission during the period from the other transmission to the transmission on the selected resource. With this configuration, PSCCH / PSSCH transmission in resource allocation mode 2 can be efficiently performed in the unlicensed band.

[0241] When another reception is being performed before the transmission on the selected resource, the controller may perform the transmission during the period from the other reception to the transmission on the selected resource. With this configuration, PSCCH / PSSCH transmission in resource allocation mode 2 can be efficiently performed in the unlicensed band.

[0242] Furthermore, according to an embodiment of the present invention, there is provided a communication method in which a terminal executes a receiving procedure for receiving signals from other terminals and performing sensing in a resource pool in an unlicensed band, a control procedure for selecting resources to be used for transmission from the resource pool based on the results of the sensing, a transmitting procedure for transmitting signals to other terminals in the selected resources, and a procedure for performing LBT (Listen before talk) for a certain period in the symbol immediately before the selected resource or the first symbol of the selected resource.

[0243] With the above configuration, in the unlicensed band, terminal 20 can perform PSCCH / PSSCH transmission in resource allocation mode 2 so as to satisfy regulations. In other words, it is possible to perform direct terminal-to-terminal communication that satisfies regulations in the unlicensed band.

[0244] (Supplementary explanation of the embodiment) 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; two or more items may be combined as needed, and items described in one item may apply to items described in another item (unless inconsistent). The boundaries between functional units or processing units in the functional block diagram do not necessarily correspond to the 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 the 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. However, such devices may be implemented using 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, registers, hard disk (HDD), removable disk, CD-ROM, database, server or any other suitable storage medium.

[0245] 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.

[0246] Each aspect / embodiment described in the present disclosure may be any of the following: LTE (Long Term Evolution), LTE-Advanced (LTE-A), 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 decimal number)), 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 The present invention may be applied to at least one of systems using 802.20, UWB (Ultra-Wideband), Bluetooth (registered trademark), or other appropriate systems, and next-generation systems that are extended, modified, created, or defined based on these systems. The present invention may also be applied to a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A with 5G).

[0247] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described herein may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order and are not limited to the particular order presented.

[0248] In this specification, a specific operation that is described as being performed by the base station 10 may also 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).

[0249] The information or signals 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.

[0250] 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 sent to another device.

[0251] In the present disclosure, the determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0252] 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.

[0253] 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.

[0254] 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.

[0255] Note that terms explained 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.

[0256] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0257] 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.

[0258] 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.

[0259] In this 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. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0260] 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 divided into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (RRH: Remote Radio Head)). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or base station subsystem that provides communication service within this coverage.

[0261] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0262] 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.

[0263] At least one of the base station and the mobile station may be called 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 body, or the mobile body itself. The mobile body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (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 also include devices that do 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.

[0264] 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 a plurality of terminals 20 (which may be called, for example, D2D (Device-to-Device) or V2X (Vehicle-to-Everything)). 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.

[0265] 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.

[0266] 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.

[0267] 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.

[0268] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.

[0269] 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."

[0270] 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.

[0271] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0272] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0273] 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.

[0274] Numerology may be communication parameters that apply to at least one of transmission and 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, and specific windowing operations performed by the transceiver in the time domain.

[0275] 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.

[0276] 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.

[0277] 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.

[0278] 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.

[0279] 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.

[0280] 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.

[0281] 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.

[0282] 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.

[0283] 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 equal to or greater than 1 ms.

[0284] A resource block (RB) is a resource allocation unit in the time domain and 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 numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

[0285] 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.

[0286] 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, or the like.

[0287] 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.

[0288] 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 given BWP and numbered within that BWP.

[0289] 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.

[0290] 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."

[0291] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, 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. may be changed in various ways.

[0292] 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.

[0293] 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."

[0294] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, notification of predetermined information (e.g., notification that "X is true") is not limited to being done explicitly, but may be done implicitly (e.g., by not notifying the predetermined information).

[0295] 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. [Explanation of symbols]

[0296] 10 base station 110 Transmitter 120 Receiver 130 Setting section 140 Control Unit 20 terminals 210 Transmitter 220 Receiving unit 230 Setting Section 240 Control Unit 1001 processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication equipment 1005 Input Device 1006 Output Device 2001 Vehicle 2002 Drive unit 2003 Steering Section 2004 accelerator pedal 2005 brake pedal 2006 Shift Lever 2007 front wheel 2008 rear wheel 2009 Axle 2010 Electronic Control Unit 2012 Information Services Department 2013 Communication Module 2021 Current Sensor 2022 RPM Sensor 2023 Air 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 Systems Department 2031 microprocessor 2032 memory (ROM, RAM) 2033 Communication port (IO port)

Claims

1. a control unit that determines resources for transmitting a shared channel in a resource pool in a frequency band that performs LBT (Listen before talk) in channel access; a transmitter that transmits the shared channel to another terminal using the determined resource; When the control unit has performed another transmission before the transmission in the determined resource, the control unit transmits the shared channel using at least a part of the period between the resource in which the other transmission was performed and the determined resource.

2. The terminal according to claim 1 , wherein the control unit sets the at least part of the period based on a subcarrier spacing used for transmission of the shared channel.

3. The terminal of claim 1, wherein the control unit, when receiving a signal from another terminal before transmitting the shared channel, performs transmission of the shared channel without performing LBT if the gap between the end of the reception and the start of the transmission is less than a predetermined value.

4. A procedure for determining resources for transmitting a shared channel in a resource pool in a frequency band that performs LBT (Listen before talk) in channel access; and a procedure of transmitting the shared channel to another terminal using the determined resource; A communication method for a terminal, in which, in the transmission procedure, if another transmission has been performed before the transmission on the determined resource, the terminal transmits on the shared channel using at least a part of the period between the resource on which the other transmission was performed and the determined resource.

5. In a communication system for direct communication between terminals, a control unit that determines resources for transmitting a shared channel in a resource pool in a frequency band that performs LBT (Listen before talk) in channel access; a transmitter that transmits the shared channel to another terminal using the determined resource; the control unit, when performing another transmission before the transmission on the determined resource, performs transmission on the shared channel using at least a part of a period between the resource on which the other transmission was performed and the determined resource; a second terminal that transmits, to the first terminal, feedback information regarding the shared channel transmitted by the first terminal.

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