Terminals and communication methods

Abstract

The present invention provides a terminal including: a control unit that specifies the composition of a resource pool in an unlicensed band on the basis of parameters specifying resources in the frequency domain; a reception unit that receives a signal in the resource pool from another terminal; and a transmission unit that transmits a signal in the resource pool to another terminal, wherein the control unit sets a time for executing a channel access procedure in the resource pool.

Description

[Technical Field]

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

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

[0003] D2D reduces traffic between terminals and base stations, enabling communication between terminals even if base stations become inoperable during disasters or other emergencies. While 3GPP (3rd Generation Partnership Project) refers to D2D as "sidelink," this specification uses the more general term D2D. However, sidelink will also be used as needed in the descriptions of embodiments later.

[0004] D2D communication is broadly divided into D2D discovery (also called D2D discovery) for finding other terminals that can communicate, and D2D direct communication (also called D2D communication, terminal-to-terminal direct communication, etc.) for direct communication between terminals. In the following, unless specifically distinguished, D2D communication, D2D discovery, etc., will simply be referred to as D2D. Also, signals transmitted and received via D2D will be called D2D signals. Various use cases for V2X (Vehicle to Everything) services in NR are being considered (for example, Non-Patent Document 2).

[0005] Furthermore, NR Release 17 explores the use of higher frequency bands than those described in previous releases (e.g., Non-Patent Document 3). For example, it examines applicable neurology, including subcarrier spacing and channel bandwidth, physical layer design, and anticipated interferences in actual wireless communication in the frequency band from 52.6 GHz to 71 GHz. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] 3GPP TS 38.211 V16.8.0(2021-12) [Non-Patent Document 2] 3GPP TR 22.886 V15.1.0(2017-03) [Non-Patent Document 3] 3GPP TS 38.306 V16.7.0(2021-12) [Non-Patent Document 4] 3GPP TS 37.213 V16.7.0(2021-12) [Non-Patent Document 5] 3GPP TS 38.331 V16.7.0(2021-12) [Non-Patent Document 6] 3GPP TS 38.214 V16.8.0(2021-12) [Non-Patent Document 7] 3GPP TS 38.101-1 V16.10.0(2021-12) [Non-Patent Document 8] 3GPP TS 38.321 V16.7.0(2021-12) [Overview of the project] [Problems that the invention aims to solve]

[0007] In a frequency band that newly uses a higher frequency than before, an unlicensed band is defined. In the unlicensed band, various regulations are defined. For example, LBT (Listen before talk) is executed when accessing a channel. When performing D2D communication in the high-frequency band, an operation that conforms to the regulations in the unlicensed band is required.

[0008] The present invention has been made in view of the above points, and an object thereof is to execute direct communication between terminals that satisfies the regulations in the unlicensed band.

Means for Solving the Problems

[0009] According to the disclosed technology, In a resource pool for direct terminal-to-terminal communication in an unlicensed band, the system includes a control unit that sets up subchannels where the resource arrangement in the frequency domain is discontinuous and sets up intracell guard bands based on RRC (Radio Resource Control) signaling, and a communication unit that executes a multichannel access procedure in the subchannel, wherein the communication unit executes either type A or type B as the multichannel access procedure, and when executing type B as the multichannel access procedure, it randomly selects a channel from the multichannel including the subchannel to execute the channel access procedure, the communication unit executes either type 1 or type 2 as the channel access procedure, and uses four types of channel access priority classes in the channel access procedure, and the control unit performs a terminal transmission feasibility determination based on the difference between the expected received power and the actual received power in the resources sensed in the channel access procedure. is provided.

Effects of the Invention

[0010] According to the disclosed technology, direct communication between terminals that satisfies the regulations in the unlicensed band can be executed.

Brief Description of the Drawings

[0011] [Figure 1] It is a diagram for explaining V2X. [Figure 2] It is a diagram showing an example of a frequency range in an embodiment of the present invention. [Figure 3] It is a diagram showing an example of a wireless LAN channel. [Figure 4] It is a diagram for explaining an example (1) of LBT. [Figure 5] It is a diagram for explaining an example (2) of LBT. [Figure 6] It is a diagram for explaining an example (3) of LBT. [Figure 7] It is a diagram showing an example (1) of regulations related to the frequency region of LBT. [Figure 8] It is a diagram showing an example (2) of regulations related to the frequency region of LBT. [Figure 9]This figure shows an example (3) of the specifications related to the frequency domain of LBT. [Figure 10] This figure shows an example (4) of the specifications related to the frequency domain of LBT. [Figure 11] This figure shows an example of a guard band. [Figure 12] This figure shows an example of an LBT in an embodiment of the present invention. [Figure 13] This figure shows an example of a side link in an embodiment of the present invention. [Figure 14] This figure shows an example of a guard band in an embodiment of the present invention. [Figure 15] This figure illustrates an example of an LBT in a side link according to an embodiment of the present invention. [Figure 16] This figure shows an example of the functional configuration of the base station 10 in an embodiment of the present invention. [Figure 17] This figure shows an example of the functional configuration of terminal 20 in an embodiment of the present invention. [Figure 18] This figure shows an example of the hardware configuration of a base station 10 or terminal 20 in an embodiment of the present invention. [Figure 19] This figure shows an example of the configuration of a vehicle 2001 in an embodiment of the present invention. [Modes for carrying out the invention]

[0012] Embodiments of the present invention will be described below with reference to the drawings. Note that the embodiments described below are examples, and the embodiments to which the present invention is applied are not limited to those described below.

[0013] In the operation of the wireless communication system according to the embodiments of the present invention, existing technologies may be used as appropriate. However, such existing technologies include, for example, existing LTE, but are not limited to existing LTE. Furthermore, the term "LTE" as used herein has a broad meaning that includes LTE-Advanced and LTE-Advanced and later methods (e.g., NR), or 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 any other method (for example, a Flexible Duplex).

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

[0016] Figure 1 is a diagram illustrating V2X. 3GPP is considering and working on specifications to realize V2X (Vehicle to Everything) or eV2X (enhanced V2X) by extending D2D functionality. As shown in Figure 1, V2X is a part of ITS (Intelligent Transport Systems) and is a general term encompassing V2V (Vehicle to Vehicle), which refers to communication between vehicles; V2I (Vehicle to Infrastructure), which refers to communication between vehicles and roadside units (RSUs) installed along the roadside; V2N (Vehicle to Network), which refers to communication between vehicles and ITS servers; and V2P (Vehicle to Pedestrian), which refers to communication between vehicles and mobile terminals carried by pedestrians.

[0017] Furthermore, 3GPP is considering V2X using LTE or NR cellular communication and terminal-to-terminal communication. V2X using cellular communication is also called cellular V2X. For NR V2X, research is underway to achieve high capacity, low latency, high reliability, and QoS (Quality of Service) control.

[0018] Regarding LTE or NR V2X, it is anticipated that future considerations will extend beyond 3GPP specifications. For example, it is expected that considerations will be given to ensuring interoperability, reducing costs through the implementation of higher layers, methods for using or switching between multiple RATs (Radio Access Technologies), compliance with regulations in various countries, and methods for data acquisition, distribution, database management, and utilization of LTE or NR V2X platforms.

[0019] While the embodiments of the present invention primarily envision a configuration in which the communication device is mounted on a vehicle, the embodiments of the present invention are not limited to this configuration. For example, the communication device may be a terminal held by a person, a device mounted on a drone or aircraft, or a base station, RSU, relay station (relay node), terminal with scheduling capabilities, etc.

[0020] Furthermore, SL (Sidelink) may be distinguished from UL (Uplink) or DL ​​(Downlink) based on any one or a combination of the following 1)-4). Also, SL may have other names. 1) Resource allocation in the time domain 2) Resource allocation in the frequency domain 3) Reference synchronization signals (including SLSS (Sidelink Synchronization Signal)) 4) Reference signal used for path loss measurement for transmit power control

[0021] Furthermore, with respect to SL or UL OFDM (Orthogonal Frequency Division Multiplexing), any of the following may be applied: CP-OFDM (Cyclic-Prefix OFDM), DFT-S-OFDM (Discrete Fourier Transform - Spread - OFDM), OFDM without transform precoding, or OFDM with transform precoding.

[0022] In LTE's Downlink Service Line (SL), Mode 3 and Mode 4 are defined for allocating SL resources to terminal 20. In Mode 3, transmission resources are dynamically allocated via DCI (Downlink Control Information) sent from base station 10 to terminal 20. Semi-Persistent Scheduling (SPS) is also possible in Mode 3. In Mode 4, terminal 20 autonomously selects transmission resources from the resource pool.

[0023] In the embodiments of the present invention, the term "slot" may be interpreted as a symbol, mini-slot, subframe, wireless frame, or TTI (Transmission Time Interval). Furthermore, in the embodiments of the present invention, the term "cell" may be interpreted as a cell group, carrier component, BWP, resource pool, resource, RAT (Radio Access Technology), system (including wireless LAN), etc.

[0024] In the embodiments of the present invention, terminal 20 is not limited to a V2X terminal, but may be any type of terminal that performs D2D communication. For example, terminal 20 may be a user-owned terminal such as a smartphone, or it may be an IoT (Internet of Things) device such as a smart meter.

[0025] 3GPP Release 16 or Release 17 sidelinks are specified for the following: 1) and 2)

[0026] 1) An environment where only 3GPP terminals exist in the ITS (Intelligent Transport Systems) band. 2) An environment that makes UL resources available to SL in the FR1 (Frequency range 1) and FR2 (Frequency range 2) license bands defined in NR.

[0027] As a sidelink for 3GPP Release 18 and later, the inclusion of unlicensed bands is being considered. Examples include unlicensed bands such as the 5GHz-7GHz band and the 60GHz band.

[0028] Figure 2 shows an example of frequency ranges in an embodiment of the present invention. The NR specification of 3GPP Release 17 considers operating in frequency bands above 52.6 GHz, for example. As shown in Figure 2, the currently defined FR1 frequency band is from 410 MHz to 7.125 GHz, with a Subcarrier Spacing (SCS) 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, using an SCS of 60, 120, or 240 kHz and a bandwidth of 50 MHz to 400 MHz. For example, the newly operated frequency band may be from 52.6 GHz to 71 GHz.

[0029] For example, unlicensed bands in the 5GHz-7GHz range could include 5.15GHz to 5.35GHz, 5.47GHz to 5.725GHz, and above 5.925GHz.

[0030] For example, unlicensed bands in the 60GHz band could include those from 59GHz to 66GHz, from 57GHz to 64GHz or 66GHz, and from 59.4GHz to 62.9GHz.

[0031] In unlicensed bands, various regulations are in place to prevent interference with other systems or equipment.

[0032] For example, in the 5GHz-7GHz band, Listen Before Talk (LBT) 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 from another device is detected, transmission is stopped. A Maximum Channel Occupancy Time (MCOT) is also specified. MCOT is the maximum time interval during which transmission is allowed to continue if transmission starts after LBT, and for example, in Japan it is 4ms. Furthermore, as an Occupied Channel Bandwidth (OCB) requirement, when transmitting using a certain carrier bandwidth, at least X% of that bandwidth must be used. For example, in Europe, it is required to use 80% to 100% of the Nominal Channel Bandwidth (NCB). The OCB requirement aims to ensure that power detection for channel access is performed correctly. In addition, regarding maximum transmit power and maximum power spectral density, it is stipulated that transmission must be performed at or below a specified transmit power. For example, in Europe, the maximum transmit power is 23 dBm in the 5150 MHz-5350 MHz band. Also, in Europe, the maximum power spectral density is 10 dBm / MHz in the 5150 MHz-5350 MHz band.

[0033] For example, in the 60GHz band, LBT 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 it detects transmission from another device, it stops transmitting. Furthermore, it is stipulated that transmission must be performed at or below a predetermined transmit power with respect to maximum transmit power and maximum power spectral density. It is also stipulated that the system must have the capability to meet OCB requirements.

[0034] Figure 3 shows an example of a wireless LAN channel. The nominal center frequency (f) of the wireless LAN channel in the 5GHz band is shown. c This may be defined by the following formula, as shown in Figure 3.

[0035] f c = 5160 + (g × 20) MHz, where 0 ≤ g ≤ 9 or 16 ≤ g ≤ 27

[0036] The nominal channel bandwidth is the maximum bandwidth, including the guard band, allocated to a single channel, and may be 20 MHz. The bandwidth allocated to the single channel being operated may be defined as the LBT bandwidth.

[0037] Occupied channel bandwidth (OCB) may also be defined as the bandwidth that includes 99 percent of the signal power.

[0038] NR specifies four types of channel access procedures, based on the differences in the behavior of LBT time reporting (the period during which sensing is performed).

[0039] Type 1) Performs variable-time sensing before transmission. Also known as Category 4 LBT. Type 2A) Performs 25μs sensing before transmission. Also known as Category 2LBT. Type 2B) Performs 16μs sensing before transmission. Also known as Category 2LBT. Type 2C) Transmission begins without LBT. Similar to transmission on licensed bands.

[0040] Figure 4 is a diagram illustrating LBT example (1). Figure 4 is an example of a Type 1 channel access procedure. Type 1 is further classified into four classes, which indicate channel access priority classes based on differences in sensing length. Sensing is performed during the following two periods.

[0041] The first period is the Prioritization Period or defer duration, which is 16 + 9 × m p It has a length of [μs]. p A fixed value is defined for each channel access priority class.

[0042] The second period is a backoff procedure having a length of 9 × N [μs]. The value of N is randomly determined from a certain range (see Non-Patent Document 4).

[0043] In the above, the 9μs sensing period may also be called the sensing slot period.

[0044] In the example in Figure 4, m p = 3, and the hold period is 43 μs. As shown in Figure 4, the backoff counter is fixed while the channel is busy. Also, as shown in Figure 4, if the transmission from NR-U gNB and wireless LAN node #2 collide and an error is detected, the contention window size is expanded from 3 to 13 in NR-U gNB.

[0045] Figure 5 is a diagram illustrating LBT example (2). Figure 5 shows an example of a Type 2A or Type 2B channel access procedure without random backoff. A gap for power detection is set before transmission for Type 2A (25 μs) and Type 2B (16 μs).

[0046] Figure 6 is a diagram illustrating example (3) of an LBT. Figure 6 shows an example of a Type 2C channel access procedure. As shown in Figure 6, no power detection is performed before transmission, and transmission is performed immediately after a gap of no more than 16 μs. The transmission period may be up to 584 μs.

[0047] As described above, the sensing period in the backoff procedure during Type 1 channel access is randomly determined from a specific range {0..CW}. The CW value is determined from the range of CWmin (minimum CW) to CWmax (maximum CW) in Table 1 below, based on the CWS (Contention Window Size) adjustment procedure defined in Non-Patent Document 4.

[0048] [Table 1]

[0049] As shown in Table 1, the minimum and maximum CW values ​​are specified differently for each channel access priority class. Higher class numbers result in larger minimum and maximum CW values. Therefore, higher class numbers reduce the likelihood of collisions with other devices and increase the time required for channel access procedures. Conversely, lower class numbers increase the likelihood of collisions with other devices and decrease the time required for channel access procedures.

[0050] The maximum COT shown in Table 1 represents the maximum channel occupancy time.

[0051] Note that in Table 1, the a / b entries indicate the value when a is gNB and the value when b is UE.

[0052] In the CWS adjustment procedure, the initial CW value is set to minimum CW. The CW value is increased based on the decoding results of past PDSCH or PUSCH transmissions.

[0053] The bandwidth of the channel on which a particular LBT senses (LBT bandwidth) may be fixed at 20 MHz. Before transmission using a broadband exceeding 20 MHz, one of the multi-channel access procedures specified in Non-Patent Document 4 shown below may be performed.

[0054] Type A multi-channel access involves operating a separate channel access procedure (LBT) for each 20MHz band. Type A multi-channel access is further divided into Type A1 and Type A2. In Type A1, CW is determined independently for each channel. In Type A2, the maximum number of CW is determined across the channels the device intends to use.

[0055] Figure 7 shows an example (1) of the specification related to the frequency domain of LBT. Figure 7 shows an example of how to determine CW for type A1. CW_P_n for channel n, CW_P_n+1 for channel n+1, and CW_P_n+2 for channel n+2 are determined independently of each other.

[0056] Figure 8 shows an example (2) of the specification related to the frequency domain of LBT. Figure 8 is an example showing the method for determining Type A1 CW. The maximum value of CW_P_n for channel n, CW_P_n+1 for channel n+1, and CW_P_n+2 for channel n+2 is determined as CW_P_max, and Type 1 LBT is performed on each channel with CW_P_max.

[0057] Type B multichannel access involves selecting a 1 LBT bandwidth (20 MHz) as the primary channel and operating the Type 1 channel access procedure on that primary channel. Then, the Type 2A channel access procedure is operated on the other channels to be used. Type B multichannel access is further divided into Type B1 and Type B2. In Type B1, a single CW is maintained across multiple channels that the device intends to use. In Type B2, CW is maintained independently on each channel.

[0058] Figure 9 shows an example (3) of the specification relating to the frequency domain of LBT. Figure 9 shows the first step of type B multichannel access. The primary channel is determined randomly or selected at intervals of 1 second or more. Figure 9 shows an example where channel n+1 is determined to be the primary channel. On the primary channel, the device runs type 1 LBT in CW_P.

[0059] Figure 10 shows an example (4) of the specification relating to the frequency domain of LBT. Figure 10 shows the second step of Type B multichannel access. Figure 10 shows an example in which channel n+1 is determined to be the primary channel. On channel n+1, which is the primary channel, the device performs Type 1 LBT in CW_P, and then performs Type 2A LBT on channels n and n+2.

[0060] In Type B1, CW_P is determined based on the decoding results of PDSCH / PUSCH for all channels. In Type B2, CW_P is determined based on the decoding result of the primary channel.

[0061] Figure 11 shows an example of a guard band. An intracell guard band may also refer to a guard band between LBT bandwidths when a single cell contains multiple LBT bandwidths, as defined for 3GPP Release 16. RBs contained within the guard band cannot be used.

[0062] When the RRC parameter IntraCellGuardBandsPerSCS is set (see Non-Patent Document 5), as shown in Figure 11, the guard band inside the BWP has its starting position set by the parameter startCRB and its width set by the parameter nrofCRB. Furthermore, the guard band may be set based on Non-Patent Document 6. If the RRC parameter IntraCellGuardBandsPerSCS is not set, the guard band may be set based on Non-Patent Document 7.

[0063] Here, we will explain resource pools in sidelinks. Table 2 shows some of the resource pool configurations in sidelinks.

[0064] [Table 2]

[0065] As shown in Table 2, each SCS has a defined minimum subchannel size, maximum subchannel size, and maximum configurable bandwidth. When the subchannel frequency domain size is expressed in terms of PRB numbers, settings of {10, 12, 15, 20, 25, 50, 75, 100} may be available. The number of subchannels in a resource pool may be configurable from 1 to 27.

[0066] As a limitation of subchannels in resource pools, resource pools consist only of consecutive RBs and only of consecutive subchannels.

[0067] Figure 12 shows an example of LBT in an embodiment of the present invention. In Resource allocation mode 2, terminal 20 selects and transmits a resource. As shown in Figure 12, terminal 20 performs sensing in a sensing window within the resource pool. Through sensing, terminal 20 receives a resource reservation field or a resource assignment field contained in the SCI (Sidelink Control Information) transmitted from another terminal 20, and identifies available resource candidates in the resource selection window within the resource pool based on these fields. Subsequently, terminal 20 randomly selects a resource from the available resource candidates.

[0068] Furthermore, as shown in Figure 12, the resource pool settings may have a period. For example, the period may be a duration of 10240 milliseconds. Figure 12 shows slot t0 SL From slot t Tmax-1 SL This is an example of how the resource pool is configured. The resource pool within each period may be defined by, for example, a bitmap.

[0069] Also, as shown in FIG. 12, the transmission trigger in the terminal 20 occurs in slot n, and the priority of the transmission is p TX Let's assume so. The terminal 20, in the sensing window from slot n - T0 to the slot immediately before slot n - T proc,0 For example, it can detect that another terminal 20 is performing a transmission with priority p RX If an SCI is detected within the sensing window and the RSRP (Reference Signal Received Power) exceeds the threshold, the resources within the resource selection window corresponding to the SCI are excluded. Also, if an SCI is detected within the sensing window and the RSRP is less than the threshold, the resources within the resource selection window corresponding to the SCI are not excluded. The threshold may be, for example, a threshold Th TX set or defined for each resource within the sensing window based on priority p RX and priority p pTX,pRX It may also be the case

[0070] Also, as shown in slot t m SL in FIG. 12, for example, for transmission, the resources within the resource selection window that are candidates for resource reservation information corresponding to the resources in the sensing window that were not monitored are excluded

[0071] As shown in FIG. 12, for the resource selection window from slot n + T1 to slot n + T2, the resources occupied by other UEs are identified, and the resources from which such resources are excluded become candidates for available resources. Let the set of available resource candidates be S A If S A is less than 20% of the resource selection window, the threshold Th pTX,pRX set for each resource in the sensing window may be increased by 3 dB and the resource identification may be performed again. That is, by increasing the threshold Th pTX,pRX and performing the resource identification again, resources that are not excluded due to the RSRP being less than the threshold are increased, and the set S of resource candidatesA It may also be necessary to ensure that it occupies 20% or more of the resource selection window. A If the resource selection window is less than 20%, the threshold Th is set for each resource in the sensing window. pTX,pRX The process of increasing the value by 3dB and re-identifying the resource may be repeated.

[0072] The lower layer of terminal 20 is S A This may be reported to the upper layer. The upper layer of terminal 20 is S A A random selection may be performed to determine which resource to use. Terminal 20 may then perform a sidelink transmission using the determined resource. For example, the upper layer may be the MAC layer, and the lower layer may be the PHY layer or the physical layer.

[0073] Although Figure 12 above illustrates the operation of the transmitting terminal 20, the receiving terminal 20 may detect data transmission from another terminal 20 based on the results of sensing or partial sensing and receive data from that other terminal 20.

[0074] Furthermore, the following two steps may be performed as part of the procedure from resource allocation in the sidelink to the actual transmission.

[0075] Step 1) Terminal 20 performs sensing and resource selection procedures in the 3GPP Release 16 / 17 sidelink, as shown in Figure 12.

[0076] Step 2) Terminal 20 executes the channel access procedure described above (3GPP Release 16 NR-U / ETSI BRAN (Broadband Radio Access Networks)) for the bandwidth corresponding to the resource selected in Step 1).

[0077] FIG. 13 is a diagram showing an example of a sidelink in an embodiment of the present invention. As shown in FIG. 13, the control signal and data signal of the sidelink may be configured. FIG. 13 is an example in which three subchannels are used for the transmission of PSCCH and PSSCH. As shown in FIG. 13, the SCI is separated into a 1st stage SCI and a 2nd stage SCI. The 1st stage SCI is transmitted via PSCCH, and the 2nd stage SCI is transmitted via PSSCH. As shown in FIG. 13, the PSCCH carrying the 1st stage SCI is composed of {10, 12, 15, 20, 25} PRB and 2 or 3 symbols without exceeding one subchannel width.

[0078] Note that for the first symbol, the second symbol is copied for AGC. The last symbol is used as a gap for transmission / reception switching.

[0079] Here, the following 1)-3) are assumed for the relationship between the subchannel and the LBT bandwidth.

[0080] 1) Subchannel = LBT bandwidth When based on the existing SL frequency region resource allocation, there is no need to consider the OCB requirement. When using multiple subchannels, it is necessary to use a multi-channel access procedure. Although simple, it is difficult to flexibly set the subchannel size.

[0081] 2) Subchannel < LBT bandwidth It is necessary to consider the OCB requirement. Multiple subchannels can be sensed with LBT for one channel. Although the subchannel size becomes flexible, it is difficult to transmit only one subchannel, and there is a possibility that the resource pool is defined in an interleaved manner.

[0082] 3) Subchannel > LBT bandwidth Since one subchannel contains multiple LBT bandwidths, a multi-channel LBT must be used even if only one subchannel is desired. Based on existing SL frequency domain resource allocations, OCB requirements do not need to be considered. Subchannels are required to be integer multiples of the LBT bandwidth. While subchannel size is flexible, the constant use of multi-channel LBTs reduces the channel access success rate.

[0083] Therefore, the bandwidth of the subchannels and resource pools that satisfy the above assumptions may be guaranteed or set. Note that a bandwidth equal to the LBT bandwidth may mean that the bandwidth is 20 MHz or an integer multiple of 20 MHz, or that the bandwidth is 80% of 20 MHz or 80% of an integer multiple of 20 MHz, i.e., a bandwidth that satisfies the OCB requirements.

[0084] In sidelink communication over an unlicensed band, terminal 20 may assume that only certain values ​​from the set of configurable values ​​are applied to the parameters related to the resource pool configuration.

[0085] For example, the parameters relating to the resource pool configuration described above may be either or both of the following 1) and 2).

[0086] 1) Number of PRBs that make up the subchannel 2) Number of subchannels that make up the resource pool

[0087] For example, the specific value mentioned above may be either or both of the following 1) and 2).

[0088] 1) This may be a bandwidth of 80% or more of a multiple of the 20MHz or LBT bandwidth, i.e., a bandwidth that satisfies the OCB requirement, or it may be a number of PRBs of 80% or more of a multiple of the 20MHz or LBT bandwidth, i.e., a number that satisfies the OCB requirement. For example, the number of PRBs included in one subchannel may be a value included in the number of PRBs in Table 3.

[0089] [Table 3]

[0090] As shown in Table 3, the number of PRBs included in one subchannel may be 100 at SCS15kHz, 50 or 100 at SCS30kHz, and 25, 50, 75 or 100 at SCS60kHz.

[0091] 2) A value within the range of the 20MHz band for 5GHz wireless LAN as defined by the BRAN regulations. For example, the maximum number of subchannels constituting one resource pool may be 12 subchannels or 6 subchannels. If there are 12 subchannels per resource pool, a bandwidth of 1 LBT may be assumed, or if there are 6 subchannels per resource pool, a bandwidth of 2 LBT may be assumed.

[0092] Furthermore, the specific value mentioned above may be changed based on specific conditions. For example, the specific condition may be the subcarrier interval.

[0093] For example, the above settable settable values ​​may be some or all of the following 1)-3).

[0094] 1) Values ​​supported in 3GPP release 16 or 17, for example, {10, 12, 15, 20, 15, 50, 75, 100} set by the parameter sl-SubchannelSize. 2) Values ​​supported in 3GPP release 16 or 17, for example, {1...27} set by the parameter sl-NumSubchannel. 3) Values ​​newly supported in 3GPP Release 18 in addition to 1) and / or 2) above

[0095] Furthermore, in sidelink communication over the unlicensed band, new values ​​may be added to the parameters related to the resource pool configuration.

[0096] For example, the parameters relating to the resource pool configuration described above may be either or both of the following 1) and 2).

[0097] 1) Number of PRBs that make up the subchannel 2) Number of subchannels that make up the resource pool

[0098] For example, the new value mentioned above may be one of the values ​​shown below. For example, the number of PRBs constituting a subchannel (sl-SubchannelSize) may be increased by adding a candidate number of PRBs such that each subchannel satisfies the condition that 1 subchannel is between 20 × N × 0.8 MHz and 20 × N × 1 MHz.

[0099] For example, sl-SubchannelSize={10,12,15,20,25,50,75,100,125,150,175,200,225,250,275,300,350,400,450,500,550,600,700,800,900,1000,1100,1200} may also be used.

[0100] Furthermore, one subchannel may have a bandwidth of the LBT band or an integer multiple of the LBT band. Furthermore, one subchannel may have a bandwidth that satisfies the OCB requirements for the LBT band or an integer multiple of the LBT band.

[0101] Furthermore, the settings or pre-configuration methods related to the resource pool configuration may be changed from those used for sidelink communication on licensed bands for sidelink communication on unlicensed bands. For example, some or all of options 1-1) to 1-4) shown below may be applied. Note that "continuous" or "discontinuous" below may mean resource allocation in the frequency domain.

[0102] Option 1-1) One subchannel may consist of continuous or discontinuous RBs or PRBs. Option 1-2) 1. The resource pool may consist of continuous or non-contiguous RBs or PRBs. Option 1-3) A resource pool may consist of contiguous or non-contiguous subchannels. Option 1-4) One subchannel consists of consecutive RBs or PRBs, and the subchannels included in the resource pool may or may not be consecutive.

[0103] Furthermore, the settings or pre-configuration methods related to the resource pool configuration may be changed from those used for sidelink communication on the licensed band for sidelink communication on the unlicensed band. For example, some or all of the methods shown in options 2-1) and 2-5) below may be applied. Note that RB may be replaced with PRB below.

[0104] Option 2-1) A bitmap may be used to indicate whether each RB can be used for transmission of multiple RBs that may be included in a subchannel. The number of such bitmaps may be equal to the number of subchannels included in the resource pool or the maximum number of subchannels.

[0105] Option 2-2) You may also configure whether multiple RBs included in the resource pool can be used for transmission using a bitmap that indicates the availability of each RB.

[0106] Option 2-3) You may configure whether each of the multiple subchannels included in the resource pool can be used for transmission using a bitmap.

[0107] Option 2-4) If an IntraCell Guard Band is configured, the number of RBs corresponding to the IntraCell Guard Band may be set at both ends of each subchannel. The number of RBs corresponding to the IntraCell Guard Band may be defined for use, or it may be set based on configuration or pre-configuration. The setting or pre-configuration of whether or not an IntraCell Guard Band is present may be performed separately from the number of RBs corresponding to the IntraCell Guard Band described above.

[0108] Option 2-5) If an intracell guard band is set, at least a portion of the frequency resources included in the resource pool determined based on the settings or pre-settings under Options 1-1)-1-4) above may be assumed to be shifted by the amount of the frequency resources corresponding to the intracell guard band.

[0109] For example, if in a resource pool the number of subchannels N is set by sl-NumSubchannel, the lowest PRB index n is set by sl-StartRB-Subchannel, and the number of PRBs M for each subchannel is set by sl-SubchannelSize, then the frequency resources of that resource pool will be PRBs of [n,n+(N×M-1)]. Note that the notation [a,b] corresponds to PRBs from index a to index b.

[0110] In this case, if an intracell guard band is also set, and the frequency resources of the intracell guard band are PRBs of [n+x1, n+x2], then the frequency resources of the resource pool may be PRBs of [n, n+x1-1] and [n+x2+1, n+(N×M-1)]. In other words, a resource pool composed of consecutive frequency resources may be divided into two groups of frequency resources by setting an intracell guard band. However, even if the frequencies are discontinuous, they may be treated as one resource pool.

[0111] For example, options 2-1) and 2-3) above may be combined. That is, in a subchannel notified as available for transmission by the bitmap of option 2-3), the RB notified as available for transmission by the bitmap of option 2-1) can actually be used for transmission.

[0112] In the embodiment described above, terminal 20 can perform configurations that conform to the resource pool in sidelink communication on the unlicensed band.

[0113] Figure 14 shows an example of a guard band in an embodiment of the present invention. As shown in Figure 14, the definition and setting method of guard bands between LBT bandwidths in a sidelink resource or resource pool was unclear. For example, specific values ​​such as the starting position of the guard band by the parameter startCRB and the width of the guard band by the parameter nrofCRB were not defined.

[0114] Therefore, a method for defining and setting guard bands between LBT bandwidths in a sidelink resource or resource pool may be specified.

[0115] The frequency-direction resources configured as a resource pool may take intracell guard bands into consideration.

[0116] For example, the IntraCellGuard Band may be determined based on either definition and / or setting shown in 1) or 2) below.

[0117] 1) Intracell Guard Band, fixedly defined in the specifications 2) IntraCell Guard Band set by RRC signaling

[0118] For example, the IntraCell Guard Band may be set up in either of the following ways: 1) or 2).

[0119] 1) Existing resource pool settings and existing intracell guard band definitions and / or settings may be reused. Terminal 20 may consider the resource pool that is actually available to be the frequency-direction resources set in the resource pool settings, excluding the frequency-direction resources corresponding to the intracell guard band.

[0120] 2) In the resource pool settings, settings related to intracell guard bands may be added. Terminal 20 may determine the resource pool that is actually available by referring to the resource pool settings. The added parameters may be some or all of the following three parameters: Parameter startCRB: The CRB (Common Resource Block) with the smallest index among the CRBs (Common Resource Blocks) included in each guard band set in the resource pool. Parameter nrofCRB: The number of CRBs included in each guard band set in the resource pool. endCRB: The CRB with the largest index among the CRBs included in each guard band set in the resource pool.

[0121] The parameter startCRB may indicate the starting position of the intracell guard band. The parameter nrofCRB may indicate the length of the intracell guard band. The parameter endCRB may indicate the ending position of the intracell guard band.

[0122] The term "intra-cell guard band" may also refer to bandwidth included in the resource pool but not used for actual SL transmission and / or reception, or it may be replaced with one of the following expressions: 1) Intra-Resource Pool Guard Band; 2) In-Resource Pool Guard Band.

[0123] Furthermore, a guard band configured or pre-configured within a resource pool may have the following relationship with the subchannels configured within that resource pool.

[0124] For example, terminal 20 does not need to assume that any subchannel in the resource pool that partially or completely overlaps with the guard band will be used for transmission and / or reception in sidelink communication.

[0125] For example, terminal 20 does not have to assume that it will use subchannels in the resource pool that completely overlap with the guard band for transmission and / or reception in sidelink communication. Terminal 20 may assume that it will use subchannels in the resource pool that partially overlap with the guard band for transmission and / or reception in sidelink communication. It may also assume that it will use only the bandwidth of the subchannel that does not overlap with the guard band for transmission and / or reception in sidelink communication.

[0126] In the embodiment described above, terminal 20 can perform settings related to a guard band that is compatible with the resource pool in sidelink communication on an unlicensed band.

[0127] Furthermore, it was unclear how to apply the channel access procedure to sidelink communication for multiple LBT hand widths. For example, it is necessary to specify whether all existing types A1, A2, B1, and B2 are usable. Also, when using type B1 or type B2, it is necessary to specify how to select the primary channel.

[0128] Therefore, a method may be specified for applying the channel access procedure to sidelink communication for multiple LBT hand widths.

[0129] In sidelink communication over unlicensed bands, channel access procedures for multiple LBT bandwidths (1 LBT bandwidth is, for example, 20 MHz) may be all or some of the existing types A1, A2, B1, and B2. For example, only type A1 may be available. For example, only type B1 may be available. For example, only type A1 and type B1 may be available.

[0130] Regarding the configuration method for multi-channel LBT, the primary channel selection method for Type B multi-channel access may be one of the following 1)-4). Note that the primary channel may also be referred to as the primary operating channel.

[0131] 1) A subchannel may be randomly selected from those to be used, and the LBT bandwidth corresponding to the selected subchannel may be designated as the primary channel.

[0132] 2) A random LBT bandwidth may be selected from the LBT bandwidths that include the subchannels to be used and designated as the primary channel.

[0133] 3) The LBT bandwidth including the subchannel that transmits PSCCH may be used as the primary channel.

[0134] 4) The LBT bandwidth, including the subchannels of the minimum or maximum index, may be used as the primary channel.

[0135] The existing Type A1, Type A2, Type B1, and Type B2 multi-access procedures may be those specified in Non-Patent Document 4.

[0136] In the embodiment described above, terminal 20 can perform channel access procedures for multiple LBT bandwidths in sidelink communication over an unlicensed band.

[0137] Furthermore, in order to perform transmission after the LBT has operated, the LBT must determine that the channel to be used for transmission is free. Before transmission, x symbols must not be used by other devices in the same RAT on the channel to be used for transmission. Table 4 shows the minimum and maximum sensing periods required for each priority and SCS during a Type 1 channel access procedure, i.e., x expressed in terms of symbols.

[0138] [Table 4]

[0139] As shown in Table 4, the minimum and maximum values ​​of x are defined. Here, the pre-transmission x symbol did not have a way to guarantee that the channel used for transmission was not being used by other devices in the same RAT.

[0140] Therefore, a method may be specified to ensure that the channel used for transmission is not used by other devices within the same RAT.

[0141] The channel access procedures used in sidelink communication may be limited. For example, the types of channel access procedures may be limited. For example, the channel access priority to be set for type 1 channel access may be limited.

[0142] Additionally, a time limit may be defined for performing the channel access procedure, or a time limit may be defined for performing the LBT.

[0143] Furthermore, in sidelink communication, in part or all of the sensing procedure, resource identification procedure, and resource selection procedure, terminal 20 may perform resource identification and / or resource selection by considering resources included in a certain period prior to the resource reserved by another UE as reserved resources.

[0144] Furthermore, in sidelink communication on an unlicensed band, terminal 20 may determine whether transmission is permitted for a given subchannel-slot resource based on the difference between the expected received power and the actual received power in at least the slot and / or subchannel containing the resource to be sensed.

[0145] Furthermore, the channel access procedures used in sidelink communication may be limited. For example, a particular type of channel access procedure may be used in sidelink communication over an unlicensed band. This particular channel access type may be a type 1 channel access, a type 2 channel access, or one or more of types 2A, 2B, and 2C, or a type 3 channel access.

[0146] For example, when Type 1 channel access is used in sidelink communication over an unlicensed band, a specific channel access priority class may be available. For example, this specific channel access priority class may be one or more of the following 1)-4):

[0147] 1) Channel access priority class 1 2) Channel access priority class 2 3) Channel access priority class 3 4) Channel access priority class 4

[0148] For example, a value less than or equal to X may be used as the channel access priority class. X may be 1, 2, 3, or 4.

[0149] Additionally, you may define the time required for channel access procedures or LBT to operate, or the time during which no transmission is performed.

[0150] For example, when transmitting in a slot, it is not necessary to transmit at the first X symbol in that slot. Alternatively, for example, transmission may not be performed at the first X symbol in that slot, and transmission may start from the (X+1) symbol. The transmission of the (X+1) symbol may be identical (repetition) to the transmission of the (X+2) symbol.

[0151] X may be a variable value depending on one of the following. For example, X may be determined based on the SCS. For example, X may be 1 for SCS 15kHz, X may be 2 for SCS 30kHz, and X may be 4 for SCS 60kHz. Alternatively, for example, a new value may be defined for sidelink communication on the unlicensed band by subtracting 1 from the above value, taking into account the guard period of the last symbol of the slot as defined in 3GPP Release 16. Alternatively, for example, X may be determined based on the channel access priority class, or based on a configurable channel access priority class. Alternatively, for example, X may be determined based on the type of channel access procedure to operate for transmission in that slot.

[0152] For example, when performing sidelink communication on an unlicensed band, the number of symbols used for SL in one slot (e.g., the parameter sl-LengthSymbols) may be assumed to be less than or equal to a predetermined value, and this predetermined value may be determined based on the channel access procedure or LBT characteristics that can be performed (e.g., minimum sensing period or maximum sensing period).

[0153] For example, when performing sidelink communication on an unlicensed band, the starting position of the symbol used for SL in one slot (e.g., parameter sl-StartSymbol) may be assumed to be greater than or equal to a predetermined value, and this predetermined value may be determined based on the channel access procedure or LBT characteristics that can be performed (e.g., minimum sensing period or maximum sensing period).

[0154] Furthermore, in sidelink communication, in some or all of the sensing procedure, resource identification procedure, and resource selection procedure, terminal 20 may perform resource identification and / or resource selection by treating resources included in a certain period prior to the resource reserved by another UE as reserved resources. For example, terminal 20 may exclude resources included in a certain period prior to the resource in question from the candidates for resource selection.

[0155] The "reserved resources" mentioned above may be resources that are not included in the subset of resources defined in Non-Patent Document 6, or resources that are excluded by any of the procedures defined in Non-Patent Document 6.

[0156] The above-mentioned "certain period" may be interpreted as either 1) or 2) below. Furthermore, the channel access procedure or LBT may be limited to a specific type, or all types may be used.

[0157] 1) The minimum time required for the channel access procedure or LBT, or the number of slots corresponding to that minimum time. The number of slots may vary depending on the SCS.

[0158] 2) The maximum time required for the channel access procedure or LBT, or the number of slots corresponding to that maximum time. The number of slots may vary depending on the SCS.

[0159] The "resources included in a certain period" described above may be excluded in the resource identification procedure (see Non-Patent Document 6). For example, in the resource identification procedure, the X slots immediately preceding a single-slot resource may be excluded. X may be the time or number of slots corresponding to the "certain period" described above. Furthermore, for example, the "resources included in a certain period" may be considered in the procedures for receiving sidelink grants and transmitting SCIs (see Non-Patent Document 8).

[0160] Furthermore, in sidelink communication on an unlicensed band, terminal 20 may determine whether transmission is permitted for a given subchannel-slot resource based on the difference between the expected received power and the actual received power in at least the slot and / or subchannel containing the resource to be sensed.

[0161] Figure 15 is a diagram illustrating an example of LBT in a sidelink according to an embodiment of the present invention. For example, in Figure 15, when LBT is performed on symbols #12 and #13, terminal 20 may determine the result of LBT based on the difference between the RSRP value calculated from the PSCCH / PSSCH reception transmitted on another symbol (any of symbols #1 to #11) and the RSRP value measured or calculated on symbols #12 and #13.

[0162] If an RSRP of X dB or higher is measured for symbols #12 and #13 compared to other symbols, terminal 20 may determine that LBT has failed. In other words, terminal 20 may consider that interference has been detected.

[0163] On the other hand, if an RSRP lower than or equal to RSRP+XdB is measured for symbol #12 and symbol #13, terminal 20 may determine that LBT was successful. In other words, terminal 20 may be considered not to have detected interference.

[0164] The above operation may also be applied to symbol #14. When the above operation is applied to symbol #14, terminal 20 may determine the LBT result based on the difference between the RSRP value obtained by applying a predetermined correction to the RSRP value calculated from the reception of PSCCH / PSSCH transmitted by other symbols, and the RSRP value measured or calculated by symbol #14. The predetermined correction may be a correction corresponding to the transition period after transmission of symbol #13 in the transmitting UE.

[0165] In the above embodiment, terminal 20 can confirm that the channel used for transmission in sidelink communication on the unlicensed band is not used by other devices located in the same RAT.

[0166] In the above embodiment, "configuration" may be replaced with "pre-configuration".

[0167] The above-described embodiment may be applied to an operation in which one terminal 20 sets or allocates transmission resources for another terminal 20.

[0168] The above-described embodiment is not limited to V2X terminals, but may also be applied to terminals that perform D2D communication.

[0169] The above embodiment makes it possible to perform direct terminal-to-terminal communication that satisfies the requirements in the unlicensed band.

[0170] (Device configuration) Next, we will describe an example of the functional configuration of the base station 10 and terminal 20 that perform the processes and operations described above. The base station 10 and terminal 20 include functions to implement the embodiments described above. However, the base station 10 and terminal 20 may each have only some of the functions in the embodiments.

[0171] <Base station 10> Figure 16 shows an example of the functional configuration of a base station 10. As shown in Figure 16, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Figure 16 is merely an example. The names of the functional categories and functional units can be anything as long as they can perform the operations according to the embodiment of the present invention.

[0172] The transmitting unit 110 includes the function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The receiving unit 120 includes the function of receiving various signals transmitted from the terminal 20 and obtaining information from the received signals, for example, information from a higher layer. The transmitting unit 110 also has the function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, DL reference signals, etc. to the terminal 20.

[0173] The setting unit 130 stores pre-configured setting information and various setting information to be transmitted to the terminal 20 in a storage device, and reads it from the storage device as needed. The contents of the setting information include, for example, information related to D2D communication settings.

[0174] As described in the embodiment, the control unit 140 performs processing related to the settings for the terminal 20 to perform D2D communication. The control unit 140 also transmits the scheduling of D2D communication and DL communication to the terminal 20 via the transmission unit 110. The control unit 140 also receives information related to the HARQ response of D2D communication and DL communication from the terminal 20 via the reception unit 120. The signal transmission function unit of the control unit 140 may be included in the transmission unit 110, and the signal reception function unit of the control unit 140 may be included in the reception unit 120.

[0175] <Terminal 20> Figure 17 shows an example of the functional configuration of terminal 20. As shown in Figure 17, 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 Figure 17 is merely an example. The names of the functional categories and functional units can be anything as long as they can perform the operations according to the embodiment of the present invention.

[0176] The transmitting unit 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The receiving unit 220 wirelessly receives various signals and acquires signals from higher layers from the received physical layer signals. The receiving unit 220 also has the function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signals or reference signals transmitted from the base station 10. For example, the transmitting unit 210 transmits PSCCH (Physical Sidelink Control Channel), PSSCH (Physical Sidelink Shared Channel), PSDCH (Physical Sidelink Discovery Channel), PSBCH (Physical Sidelink Broadcast Channel), etc. to other terminals 20 as D2D communication, and the receiving unit 220 receives PSCCH, PSSCH, PSDCH or PSBCH, etc. from other terminals 20.

[0177] The setting unit 230 stores various setting information received from the base station 10 or terminal 20 by the receiving unit 220 in its storage device and reads it from the storage device as needed. The setting unit 230 also stores pre-configured setting information. The content of the setting information is, for example, information related to D2D communication settings.

[0178] As described in the embodiment, the control unit 240 controls D2D communication to establish an RRC connection with other terminals 20. The control unit 240 also performs power-saving operations. The control unit 240 also performs HARQ processing for D2D and DL communication. The control unit 240 transmits information related to the HARQ response for D2D and DL communication scheduled from the base station 10 to the base station 10. The control unit 240 may also schedule D2D communication with other terminals 20. The control unit 240 may also autonomously select resources to be used for D2D communication from a resource selection window based on sensing results, or it may perform re-evaluation or preemption. The control unit 240 also performs power-saving processing for D2D communication transmission and reception. The control unit 240 also performs processing related to inter-terminal coordination in D2D communication. The signal transmission function unit of the control unit 240 may be included in the transmission unit 210, and the signal reception function unit of the control unit 240 may be included in the reception unit 220.

[0179] (Hardware configuration) The block diagrams (Figures 16 and 17) used in the description of the above embodiments show functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or it may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may be realized by combining the above one device or the above multiple devices with software.

[0180] Functions include, but are not limited to, judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, exploration, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, assumption, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating (mapping), and assigning. For example, a functional block (configuration part) that enables transmission is called a transmitting unit or transmitter. As mentioned above, the method of implementation is not particularly limited.

[0181] For example, the base station 10, terminal 20, etc. in one embodiment of the present disclosure may function as a computer that processes the wireless communication method of the present disclosure. Figure 18 is a diagram showing an example of the hardware configuration of the base station 10 and terminal 20 according to one embodiment of the present disclosure. The above-mentioned base station 10 and terminal 20 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.

[0182] In the following explanation, the term "device" can be read as "circuit," "device," "unit," etc. The hardware configuration of the base station 10 and terminal 20 may include one or more of the devices shown in the figure, or it may be configured without some of the devices.

[0183] Each function in the base station 10 and terminal 20 is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and storage device 1002, which allows the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of the reading and writing of data in the storage device 1002 and auxiliary storage device 1003.

[0184] The processor 1001 controls the entire computer, for example, by running an operating system. The processor 1001 may consist of a central processing unit (CPU) that includes interfaces with peripheral devices, control devices, arithmetic units, registers, etc. For example, the control unit 140, control unit 240, etc., described above may be implemented by the processor 1001.

[0185] Furthermore, the processor 1001 reads programs (program code), software modules, or data from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes accordingly. The program used is one that causes a computer to execute at least a part of the operations described in the above embodiment. For example, the control unit 140 of the base station 10 shown in Figure 16 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Also, for example, the control unit 240 of the terminal 20 shown in Figure 17 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Although the above processes have been described as being executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The program may be transmitted from the network via a telecommunications line.

[0186] The storage device 1002 is a computer-readable recording medium and may consist of at least one of the following: ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), etc. The storage device 1002 may also be called a register, cache, main memory, etc. The storage device 1002 can store executable programs (program code), software modules, etc., for implementing a communication method according to one embodiment of this disclosure.

[0187] The auxiliary storage device 1003 is a computer-readable recording medium and may consist of at least one of the following: an optical disc such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disc, a digital multipurpose disc, a Blu-ray® disc), a smart card, flash memory (e.g., a card, a stick, a key drive), a floppy® disk, a magnetic strip, etc. The above-mentioned storage medium may also be a database, server, or other suitable medium that includes at least one of the storage device 1002 and the auxiliary storage device 1003.

[0188] The communication device 1004 is hardware (transceiver / receiver device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, communication module, etc. The communication device 1004 may include high-frequency switches, duplexers, filters, frequency synthesizers, etc., to implement at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the transmit / receive antenna, amplifier section, transmit / receive section, transmission path interface, etc., may be implemented by the communication device 1004. The transmit / receive section may be implemented with physically or logically separated transmitting and receiving sections.

[0189] The input device 1005 is an input device that accepts input from an external source (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to an external source (e.g., a display, speaker, LED lamp, etc.). The input device 1005 and the output device 1006 may be configured as an integrated unit (e.g., a touch panel).

[0190] 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 different buses may be configured for each device.

[0191] Furthermore, the base station 10 and terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array), and some or all of each functional block may be realized by such hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0192] Figure 19 shows an example of the configuration of vehicle 2001. As shown in Figure 19, vehicle 2001 comprises 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 2021-2029, an information service unit 2012, and a communication module 2013. Each aspect / embodiment described in this disclosure may be applied to a communication device mounted on vehicle 2001, for example, to the communication module 2013.

[0193] The drive unit 2002 consists of, for example, 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, which is operated by the user.

[0194] The electronic control unit 2010 consists of a microprocessor 2031, memory (ROM, RAM) 2032, and communication ports (IO ports) 2033. Signals from various sensors 2021 to 2029 installed in the vehicle 2001 are input to the electronic control unit 2010. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0195] Signals from various sensors 2021-2029 include current signals from current sensor 2021 which senses motor current, front and rear wheel rotation speed signals obtained by rotation speed sensor 2022, front and rear wheel air pressure signals obtained by air pressure sensor 2023, vehicle speed signals obtained by vehicle speed sensor 2024, acceleration signals obtained by acceleration sensor 2025, accelerator pedal depression signals obtained by accelerator pedal sensor 2029, brake pedal depression signals obtained by brake pedal sensor 2026, shift lever operation signals obtained by shift lever sensor 2027, and detection signals obtained by object detection sensor 2028 for detecting obstacles, vehicles, pedestrians, etc.

[0196] The Information Services Unit 2012 consists of various devices for providing various types of information, such as driving information, traffic information, and entertainment information, including a car navigation system, audio system, speakers, television, and radio, and one or more ECUs that control these devices. The Information Services Unit 2012 uses information acquired from external devices via a communication module 2013, etc., to provide various multimedia information and multimedia services to the occupants of the vehicle 2001.

[0197] The driver assistance system unit 2030 consists of various devices that provide functions to prevent accidents or reduce the driver's workload, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. The driver assistance system unit 2030 also sends and receives various information via the communication module 2013 to realize driver assistance functions or autonomous driving functions.

[0198] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via its communication port. For example, the communication module 2013 sends and receives data via its communication port 2033 to the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, the microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021-29 provided in the vehicle 2001.

[0199] 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 external devices. For example, it can send and receive various types of information to and from external devices 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 or a mobile station.

[0200] The communication module 2013 transmits current signals from current sensors input to the electronic control unit 2010 to an external device via wireless communication. The communication module 2013 also transmits, via wireless communication, other signals input to the electronic control unit 2010, including front and rear wheel rotation speed signals obtained by the rotation speed sensor 2022, front and rear wheel air pressure signals obtained by the air pressure sensor 2023, vehicle speed signals obtained by the vehicle speed sensor 2024, acceleration signals obtained by the acceleration sensor 2025, accelerator pedal depression signals obtained by the accelerator pedal sensor 2029, brake pedal depression signals obtained by the brake pedal sensor 2026, shift lever operation signals obtained by the shift lever sensor 2027, and detection signals obtained by the object detection sensor 2028 for detecting obstacles, vehicles, pedestrians, etc.

[0201] The communication module 2013 receives various information (traffic information, signal information, distance information, etc.) transmitted from an external device and displays it on the information service unit 2012 installed in the vehicle 2001. The communication module 2013 also stores the various information received from the external device in memory 2032, which is available to the microprocessor 2031. Based on the information stored in memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021-2029, etc., installed in the vehicle 2001.

[0202] (Summary of the embodiments) As described above, according to an embodiment of the present invention, the system includes a control unit that identifies the configuration of a resource pool in an unlicensed band based on a parameter that specifies resources in the frequency domain, a receiving unit that receives signals from other terminals in the resource pool, and a transmitting unit that transmits signals to other terminals in the resource pool, wherein the control unit is provided with a terminal that sets a time for executing a channel access procedure in the resource pool.

[0203] With the above configuration, terminal 20 can confirm that the channel used for transmission in sidelink communication on the unlicensed band is not being used by other devices located in the same RAT. In other words, it can perform direct terminal-to-terminal communication that satisfies the requirements for the unlicensed band.

[0204] When the control unit performs a transmission in a slot, it does not need to perform a transmission for a certain number of symbols at the beginning of that slot. With this configuration, terminal 20 can confirm that the channel used for transmission in sidelink communication on the unlicensed band is not being used by other devices located in the same RAT.

[0205] The control unit may determine the number based on the subcarrier interval or channel access priority class. With this configuration, terminal 20 can confirm that the channel used for transmission in sidelink communication on the unlicensed band is not used by other devices located in the same RAT.

[0206] When the control unit performs resource selection in the resource pool, it may exclude a certain period prior to a resource reserved by another terminal from the list of candidates for resource selection. With this configuration, terminal 20 can confirm that the channel used for transmission in sidelink communication on the unlicensed band is not used by another device located in the same RAT.

[0207] When the control unit performs sensing in a slot, it may determine whether transmission is permitted based on the difference between the expected received power for the symbol to be sensed in that slot and the received power measured for the symbol to be sensed. With this configuration, the terminal 20 can confirm that the channel used for transmission in sidelink communication on the unlicensed band is not being used by other devices located in the same RAT.

[0208] Furthermore, according to embodiments of the present invention, a communication method is provided in which a terminal performs a control procedure to identify the configuration of a resource pool in an unlicensed band based on a parameter that specifies a resource in the frequency domain; a reception procedure to receive a signal from another terminal in the resource pool; a transmission procedure to transmit a signal to another terminal in the resource pool; and a procedure to set a time for executing a channel access procedure in the resource pool.

[0209] With the above configuration, terminal 20 can confirm that the channel used for transmission in sidelink communication on the unlicensed band is not being used by other devices located in the same RAT. In other words, it can perform direct terminal-to-terminal communication that satisfies the requirements for the unlicensed band.

[0210] (Supplement to the embodiment) While 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, substitutions, etc. Specific numerical examples have been used to facilitate understanding of the invention, but 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, and matters described in two or more items may be combined as needed, and matters described in one item may be applied to matters described in another item (as long as they do not contradict each other). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical parts. The operation of multiple functional units may be physically performed by one part, or the operation of one functional unit may be physically performed by multiple parts. Regarding the processing procedures described in the embodiments, the order of processing may be changed as long as it does not contradict each other. For the convenience of explaining the processing, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be implemented in hardware, software, or a combination thereof. The software operated by the processor of the base station 10 according to an embodiment of the present invention and the software operated by the processor of the terminal 20 according to an embodiment of the present invention may 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.

[0211] Furthermore, the notification of information is not limited to the embodiments / models described herein and may be carried out by other methods. For example, the notification of information may be carried out by physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), upper layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling), broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or combinations thereof. Also, RRC signaling may be called RRC messages, and may be, for example, RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc.

[0212] Each aspect / embodiment described in this disclosure includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (where x is, for example, an integer or decimal)), FRA (Future Radio Access), NR (new Radio), New radio access (NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), and IEEE This may apply to at least one system utilizing 802.20, UWB (Ultra-WideBand), Bluetooth®, or other appropriate systems, and to next-generation systems extended, modified, created, or defined based thereon. It may also apply to a combination of multiple systems (for example, a combination of at least one of LTE and LTE-A with 5G).

[0213] The processing procedures, sequences, flowcharts, etc., of each aspect / embodiment described herein may be reordered, provided they are consistent with each other. For example, the methods described herein present various step elements in an exemplary order and are not limited to that specific order.

[0214] In this specification, specific operations performed by the base station 10 may, in some cases, be performed by its upper node. In a network consisting of one or more network nodes having a base station 10, it is clear that various operations performed for communication with the terminal 20 can be performed by the base station 10 and at least one of the other network nodes (for example, an MME or S-GW, but not limited to these). Although the above example illustrates the case where there is one other network node besides the base station 10, the other network node may be a combination of multiple other network nodes (for example, an MME and an S-GW).

[0215] The information or signals described in this disclosure may be output from a higher layer (or lower layer) to a lower layer (or higher layer). They may also be input and output via multiple network nodes.

[0216] Input and output information may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information may be overwritten, updated, or appended to. Output information may be deleted. Input information may be transmitted to other devices.

[0217] The determination in this disclosure may be made by a value represented by one bit (0 or 1), by a boolean value (true or false), or by a numerical comparison (for example, a comparison with a predetermined value).

[0218] Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, and so on, whether they are called software, firmware, middleware, microcode, hardware description languages, or by any other name.

[0219] Furthermore, software, instructions, information, etc., may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of wired technology (such as coaxial cable, fiber optic cable, twisted pair, or digital subscriber line (DSL)) and wireless technology (such as infrared or microwave), then at least one of these wired and wireless technologies is included in the definition of a transmission medium.

[0220] The information, signals, etc. described in this disclosure may be represented using any of the various different techniques. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0221] In addition, terms used 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 the channel and symbol may be a signal (signaling). Also, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, cell, frequency carrier, etc.

[0222] The terms “system” and “network” as used in this disclosure are interchangeable.

[0223] Furthermore, the information, parameters, etc., described in this disclosure may be expressed using absolute values, relative values ​​from a given value, or other corresponding information. For example, wireless resources may be indicated by an index.

[0224] The names used for the parameters described above are not restrictive in any way. Furthermore, the formulas and other expressions using these parameters may differ from those expressly disclosed in this disclosure. Various channels (e.g., PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, and therefore, the various names assigned to these various channels and information elements are not restrictive in any way.

[0225] In this disclosure, terms such as "Base Station (BS)", "wireless 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.

[0226] A base station can house one or more (e.g., three) cells. If a base station houses multiple cells, the entire coverage area of ​​the base station can be divided into several smaller areas, each of which may also be provided with communication services by a base station subsystem (e.g., a Remote Radio Head (RRH)). The terms “cell” or “sector” refer to part or all of the coverage area of ​​at least one of the base station and / or base station subsystems that provide communication services in that coverage.

[0227] In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.

[0228] 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 several other appropriate terms.

[0229] 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, the mobile body itself, etc. 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 be a device that does not necessarily move during communication operation. 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.

[0230] Furthermore, the term "base station" in this disclosure may be interpreted as "user terminal." For example, the various aspects / embodiments of this disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple terminals 20 (which may be called, for example, D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). In this case, the terminals 20 may have the functions that the base station 10 has. Also, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, uplink channel, downlink channel, etc., may be interpreted as side channel.

[0231] Similarly, the term "user terminal" in this disclosure may be replaced with "base station." In this case, the base station may be configured to have the same functions as the user terminal described above.

[0232] As used in this disclosure, the terms “determining” and “determining” may encompass a wide variety of actions. “Determining” may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, or inquiring (e.g., searching in a table, database, or other data structure), or ascertaining. “Determining” may also include, for example, receiving (e.g., receiving information), transmitting (e.g., sending information), inputting, outputting, or accessing (e.g., accessing data in memory). Furthermore, "judgment" and "decision" can include considering something as having been "judged" or "decided" after resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment" and "decision" can include considering something as having been "judged" or "decided" after some action. Also, "judgment (decision)" can be reinterpreted as "assuming," "expecting," or "considering."

[0233] The terms “connected,” “coupled,” or any variation thereof, mean 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” with each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, “connection” may be reinterpreted as “access.” As used in this disclosure, two elements may be considered to be “connected” or “coupled” with each other using at least one of one or more wires, cables, and printed electrical connections, and, in some non-limiting and non-exclusive examples, electromagnetic energy having wavelengths in the radio frequency domain, microwave domain, and optical (both visible and invisible) domain.

[0234] The reference signal can also be abbreviated as RS (Reference Signal), and may be called a pilot depending on the applicable standard.

[0235] In this disclosure, the phrase "based on" does not mean "based solely on" unless otherwise specified. In other words, the phrase "based on" means both "based solely on" and "based at least on."

[0236] Any reference to elements using the designations “first,” “second,” etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Accordingly, references to the first and second elements do not imply that only two elements may be employed, or that the first element must precede the second element in any way.

[0237] In the configuration of each of the above devices, "means" may be replaced with "part," "circuit," "device," etc.

[0238] Where the terms “include,” “including,” and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term “comprising.” Furthermore, the term “or” as used in this disclosure is not intended to mean exclusive OR.

[0239] A wireless frame may consist of one or more frames in the time domain. Each of these frames in the time domain may be called a subframe. A subframe may further consist 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.

[0240] Numerical logic may be communication parameters applied to at least one of the transmission and reception of a signal or channel. Numerical logic may include, for example, at least one of the following: subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, specific filtering processes performed by the transceiver in the frequency domain, and specific windowing processes performed by the transceiver in the time domain.

[0241] A slot may consist of one or more symbols in the time domain (such as OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, etc.). A slot may also be a time unit based on neurology.

[0242] A slot may include multiple minislots. Each minislot may consist of one or more symbols in the time domain. Minislots may also be called subslots. Minislots 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.

[0243] Wireless frames, subframes, slots, minislots, and symbols all represent units of time when transmitting a signal. Different names may be used for each of these terms.

[0244] 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 mini-slot may be called a TTI. In other words, at least one of a subframe and a TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, mini-slot, etc., instead of a subframe.

[0245] Here, TTI refers to, for example, the smallest unit of time for scheduling in wireless communication. For example, in an LTE system, the base station schedules each terminal 20 to allocate wireless resources (such as the frequency bandwidth and transmission power available to each terminal 20) in TTI units. However, the definition of TTI is not limited to this.

[0246] TTI may be a transmission time unit for channel-encoded data packets (transport blocks), code blocks, code words, etc., or it may be a processing unit for scheduling, link adaptation, etc. Given a TTI, the actual time interval (e.g., number of symbols) to which the transport block, code block, code word, etc. are mapped may be shorter than the given TTI.

[0247] Furthermore, if one slot or one mini-slot is referred to as TTI, then one or more TTIs (i.e., one or more slots or one or more mini-slots) may constitute the minimum time unit of scheduling. In addition, the number of slots (number of mini-slots) that constitute the minimum time unit of scheduling may be controlled.

[0248] A TTI with a time length of 1ms may also be called a normal TTI, long TTI, normal subframe, long subframe, slot, etc. A TTI shorter than a normal TTI may also be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, mini slot, sub slot, slot, etc.

[0249] Furthermore, long TTIs (e.g., normal TTIs, subframes, etc.) may be interpreted as TTIs with a time length exceeding 1 ms, and short TTIs (e.g., shortened TTIs, etc.) may be interpreted as TTIs with a TTI length less than that of a long TTI but 1 ms or more.

[0250] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and in the frequency domain, it may contain one or more consecutive subcarriers. The number of subcarriers in an RB may be the same regardless of the neurology, for example, 12. The number of subcarriers in an RB may be determined based on the neurology.

[0251] Also, the time domain of the RB may include one or more symbols and may have a length of one slot, one mini-slot, one sub-frame, or one TTI. One TTI, one sub-frame, etc. may each be composed of one or more resource blocks.

[0252] Note that one or more RBs may be referred to as physical resource blocks (PRBs), sub-carrier groups (SCGs), resource element groups (REGs), PRB pairs, RB pairs, etc.

[0253] Also, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource area of one sub-carrier and one symbol.

[0254] A bandwidth part (BWP) (which may also be called a partial bandwidth, etc.) may represent a subset of consecutive common resource blocks (common RBs) for a certain numerology in a certain carrier. Here, the common RB may be specified by the index of the RB based on the common reference point of the carrier. A PRB may be defined in a certain BWP and numbered within that BWP.

[0255] The BWP may include a BWP for UL (UL BWP) and a BWP for DL (DL BWP). For the terminal 20, one or more BWPs may be set within one carrier.

[0256] At least one of the set BWPs may be active, and the terminal 20 may not be assumed to transmit and receive a predetermined signal / channel outside the active BWP. Note that "cell", "carrier", etc. in the present disclosure may be read as "BWP".

[0257] The structures described above, such as wireless frames, subframes, slots, minislots, and symbols, are merely illustrative. For example, the number of subframes included in a wireless frame, the number of slots per subframe or wireless 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, and the number of symbols, symbol length, and cyclic prefix (CP) length within a TTI can be varied in various ways.

[0258] In this disclosure, if articles are added through translation, such as a, an, and the in English, this disclosure may include the fact that the noun following these articles is plural.

[0259] In this 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 "combine" may be interpreted similarly to "different."

[0260] Each aspect / embodiment described herein may be used individually, in combination, or switched between as needed during implementation. Furthermore, notification of specific information (e.g., notification that "X is") is not limited to explicit notification, but may also be implicit (e.g., by not providing such notification).

[0261] Although the present disclosure has been described in detail above, it will be 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 intent and scope of the present disclosure as defined by the claims. Therefore, the descriptions in the present disclosure are illustrative and not intended to be restrictive in any way. [Explanation of Symbols]

[0262] 10 Base Station 110 Transmitter 120 Receiver 130 Setting Unit 140 Control Unit 20 Terminal 210 Transmitter 220 Receiver 230 Setting Unit 240 Control Unit 1001 Processor 1002 Memory Device 1003 Auxiliary Memory Device 1004 Communication Device 1005 Input Device 1006 Output Device 2001 Vehicle 2002 Driving Unit 2003 Steering Unit 2004 Accelerator Pedal 2005 Brake Pedal 2006 Shift Lever 2007 Front Wheel 2008 Rear Wheel 2009 Axle 2010 Electronic Control Unit 2012 Information Service Unit 2013 Communication Module 2021 Current Sensor 2022 Rotation Speed 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 Support System Unit 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication Port (IO Port)

Claims

1. A resource pool for direct terminal-to-terminal communication in an unlicensed band, comprising a control unit that sets up subchannels where the resource arrangement in the frequency domain is discontinuous, and sets up an intracell guard band based on RRC (Radio Resource Control) signaling, It has a communication unit that executes a multi-channel access procedure in the subchannel, The communication unit executes either type A or type B as the multi-channel access procedure, and when executing type B as the multi-channel access procedure, it randomly selects a channel from the multi-channel including the subchannels to execute the channel access procedure. The communication unit executes type 1 or type 2 as the channel access procedure, and uses four types of channel access priority classes in the channel access procedure. The control unit is a terminal that performs a transmission feasibility determination based on the difference between the expected received power and the actual received power of the resource sensed in the channel access procedure.

2. A procedure for setting up an intracell guard band based on RRC (Radio Resource Control) signaling in a resource pool for direct terminal-to-terminal communication in an unlicensed band, which includes setting up subchannels where the resource allocation in the frequency domain is discontinuous, and A procedure for performing a multichannel access procedure in the aforementioned subchannel, A procedure to perform either type A or type B as the multi-channel access procedure, and when performing type B as the multi-channel access procedure, a procedure to randomly select a channel from the multi-channel including the subchannels to perform the channel access procedure, A procedure that performs type 1 or type 2 as the channel access procedure, and uses four types of channel access priority classes in the channel access procedure, A communication method in which a terminal performs a procedure to determine whether transmission is possible based on the difference between the expected received power and the actual received power of the resource sensed in the channel access procedure.

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