Terminals and communication methods

Abstract

To perform communication using carrier aggregation in direct communication between terminals.SOLUTION: A terminal includes a control unit that, when selecting carriers for transmitting sidelink data, selects target carriers and resource pools associated with the target carriers based on the channel busy ratios (CBRs) of the target carriers and the priority of a sidelink logical channel, and a transmitting unit that performs transmission in sidelink communication via the selected multiple carriers in the same time unit.SELECTED DRAWING: Figure 20

Description

Technical Field

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

Background Art

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

[0003] D2D reduces traffic between a terminal and a base station and enables communication between terminals even when the base station becomes incommunicable during a disaster or the like. In 3GPP (3rd Generation Partnership Project), D2D is referred to as "sidelink", but in this specification, the more general term D2D is used. However, sidelink is also used as necessary in the description of the embodiments described later.

[0004] D2D communication is roughly classified into D2D discovery (also referred to as D2D discovery) for discovering other communicable terminals and D2D communication (also referred to as D2D direct communication, D2D communication, direct communication between terminals, etc.) for directly communicating between terminals. Hereinafter, when D2D communication, D2D discovery, etc. are not particularly distinguished, they are simply referred to as D2D. Also, a signal transmitted and received by D2D is referred to as a D2D signal. Various use cases of services related to V2X (Vehicle to Everything) in NR have been studied (for example, Non-Patent Document 2).

Prior Art Documents

Non-Patent Documents

[0005]

Non-Patent Document 1

[0006] To enhance NR sidelinks, the application of carrier aggregation is being considered. However, if it operates in the same way as conventional carrier aggregation, it may be difficult to achieve the required quality and may not support the functions specified for NR sidelinks.

[0007] The present invention has been made in view of the above points, and aims to perform communication by carrier aggregation in direct communication between terminals. [Means for solving the problem]

[0008] According to the disclosed technology, a terminal is provided comprising: a control unit that selects a target carrier and a resource pool associated with the target carrier based on the Channel Busy Ratio (CBR) of the target carrier and the priority of the sidelink logical channel when selecting a carrier for transmitting sidelink data; and a transmission unit that performs transmission in sidelink communication via the selected multiple carriers within the same time unit. [Effects of the Invention]

[0009] According to the disclosed technology, communication can be performed using carrier aggregation in direct communication between terminals. [Brief explanation of the drawing]

[0010] [Figure 1] This is a diagram to explain V2X. [Figure 2] This is a diagram illustrating an example of a V2X transmission mode (1). [Figure 3] This is a diagram illustrating an example of a V2X transmission mode (2). [Figure 4] This is a diagram illustrating an example of a V2X transmission mode (3). [Figure 5] This is a diagram illustrating an example of a V2X transmission mode (4). [Figure 6] This is a diagram illustrating an example of a V2X transmission mode (5). [Figure 7] This is a diagram illustrating an example of a V2X communication type (1). [Figure 8] This is a diagram illustrating an example of a V2X communication type (2). [Figure 9] This is a diagram illustrating example (3) of V2X communication types. [Figure 10] This is a sequence diagram showing an example of V2X operation (1). [Figure 11] This is a sequence diagram showing an example of V2X operation (2). [Figure 12] This is a sequence diagram showing an example of V2X operation (3). [Figure 13] This is a sequence diagram showing an example of V2X operation (4). [Figure 14] This figure shows an example of sensing operation. [Figure 15] This is a flowchart illustrating an example of preemption behavior. [Figure 16] This figure shows an example of preemption behavior. [Figure 17] This figure shows an example of partial sensing operation. [Figure 18] This is a diagram illustrating an example of periodic partial sensing. [Figure 19]This is a diagram illustrating an example of continuous partial sensing. [Figure 20] This figure illustrates an example (1) of carrier selection in an embodiment of the present invention. [Figure 21] This figure illustrates an example (2) of carrier selection in an embodiment of the present invention. [Figure 22] This figure shows an example of the functional configuration of the base station 10 in an embodiment of the present invention. [Figure 23] This figure shows an example of the functional configuration of terminal 20 in an embodiment of the present invention. [Figure 24] 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 25] 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]

[0011] 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.

[0012] 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.

[0013] 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).

[0014] Furthermore, in 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. Also, in embodiments of the present invention, "greater than or equal to" may be replaced with "greater than," and "less than or equal to" may be replaced with "less than."

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] Figure 2 is a diagram illustrating an example of a V2X transmission mode (1). In the sidelink communication transmission mode shown in Figure 2, in step 1, the base station 10 transmits the sidelink scheduling to terminal 20A. Subsequently, terminal 20A transmits the PSCCH (Physical Sidelink Control Channel) and PSSCH (Physical Sidelink Shared Channel) to terminal 20B based on the received scheduling (step 2). The sidelink communication transmission mode shown in Figure 2 may also be called sidelink transmission mode 3 in LTE. In sidelink transmission mode 3 in LTE, Uu-based sidelink scheduling is performed. Uu is the radio interface between UTRAN (Universal Terrestrial Radio Access Network) and UE (User Equipment). The sidelink communication transmission mode shown in Figure 2 may also be called sidelink transmission mode 1 in NR.

[0025] Figure 3 is a diagram illustrating an example (2) of the V2X transmission mode. In the sidelink communication transmission mode shown in Figure 3, in step 1, terminal 20A uses autonomously selected resources to transmit PSCCH and PSSCH to terminal 20B. The sidelink communication transmission mode shown in Figure 3 may also be called sidelink transmission mode 4 in LTE. In sidelink transmission mode 4 in LTE, the UE itself performs resource selection.

[0026] Figure 4 is a diagram illustrating an example of a V2X transmission mode (3). In the sidelink communication transmission mode shown in Figure 4, in step 1, terminal 20A uses autonomously selected resources to transmit PSCCH and PSSCH to terminal 20B. Similarly, terminal 20B uses autonomously selected resources to transmit PSCCH and PSSCH to terminal 20A (step 1). The sidelink communication transmission mode shown in Figure 4 may also be called sidelink transmission mode 2a in NR. In sidelink transmission mode 2 in NR, terminal 20 itself performs resource selection.

[0027] Figure 5 is a diagram illustrating an example of a V2X transmission mode (4). In the sidelink communication transmission mode shown in Figure 5, in step 0, the sidelink resource pattern is transmitted from the base station 10 to terminal 20A via RRC (Radio Resource Control) settings, or is pre-configured. Subsequently, terminal 20A transmits PSSCH to terminal 20B based on the resource pattern (step 1). The sidelink communication transmission mode shown in Figure 5 may also be called the sidelink transmission mode 2c in NR.

[0028] Figure 6 is a diagram illustrating an example of a V2X transmission mode (5). In the sidelink communication transmission mode shown in Figure 6, in step 1, terminal 20A transmits the sidelink scheduling to terminal 20B via PSCCH. Subsequently, terminal 20B transmits PSSCH to terminal 20A based on the received scheduling (step 2). The sidelink communication transmission mode shown in Figure 6 may also be called the sidelink transmission mode 2d in NR.

[0029] Figure 7 is a diagram illustrating an example of a V2X communication type (1). The sidelink communication type shown in Figure 7 is unicast. Terminal 20A transmits PSCCH and PSSCH to Terminal 20. In the example shown in Figure 7, Terminal 20A unicasts to Terminal 20B and also unicasts to Terminal 20C.

[0030] Figure 8 is a diagram illustrating an example (2) of V2X communication types. The sidelink communication type shown in Figure 8 is a group cast. Terminal 20A sends PSCCH and PSSCH to a group to which one or more terminals 20 belong. In the example shown in Figure 8, the group includes terminals 20B and 20C, and terminal 20A performs a group cast to the group.

[0031] Figure 9 is a diagram illustrating an example of a V2X communication type (3). The sidelink communication type shown in Figure 9 is broadcast. Terminal 20A sends PSCCH and PSSCH to one or more terminals 20. In the example shown in Figure 9, terminal 20A broadcasts to terminals 20B, 20C, and 20D. Note that terminal 20A shown in Figures 7 to 9 may also be referred to as the header UE.

[0032] Furthermore, it is anticipated that NR-V2X will support HARQ (Hybrid automatic repeat request) for sidelink unicast and groupcast. In addition, NR-V2X will define SFCI (Sidelink Feedback Control Information) that includes HARQ responses. Moreover, it is being considered that SFCI will be transmitted via PSFCH (Physical Sidelink Feedback Channel).

[0033] Note that the following explanation assumes the use of PSFCH for transmitting HARQ-ACK over a sidelink, but this is just one example. For example, you may use PSCCH to transmit HARQ-ACK over a sidelink, or PSSCH, or any other channel to transmit HARQ-ACK over a sidelink.

[0034] In the following, for convenience, all information reported by terminal 20 in HARQ will be referred to as HARQ-ACK. This HARQ-ACK may also be called HARQ-ACK information. More specifically, the codebook applied to the HARQ-ACK information reported from terminal 20 to base station 10, etc., will be called the HARQ-ACK codebook. The HARQ-ACK codebook defines the bit sequence of the HARQ-ACK information. In addition to ACK, NACK is also transmitted with "HARQ-ACK".

[0035] Figure 10 is a sequence diagram showing an example of V2X operation (1). As shown in Figure 10, the wireless communication system according to the embodiment of the present invention may have terminals 20A and 20B. In reality, there are many user devices, but Figure 10 shows terminals 20A and 20B as examples.

[0036] Hereafter, unless otherwise specified, terminals 20A, 20B, etc., will simply be referred to as "terminal 20" or "user device." Figure 10 shows an example where both terminal 20A and terminal 20B are within the cell coverage, but the operation in the embodiment of the present invention can also be applied when terminal 20B is outside the coverage.

[0037] As described above, in this embodiment, terminal 20 is, for example, a device mounted on a vehicle such as an automobile, and has cellular communication functionality as a UE in LTE or NR, as well as side-link functionality. Terminal 20 may be a general mobile terminal (such as a smartphone). Alternatively, terminal 20 may be an RSU. The RSU may be a UE-type RSU with UE functionality, or a gNB-type RSU with base station functionality.

[0038] Furthermore, the terminal 20 does not need to be a single-casing device; for example, even if various sensors are distributed throughout the vehicle, the device including these various sensors may be considered the terminal 20.

[0039] Furthermore, the processing of the sidelink transmission data of terminal 20 is basically the same as the processing of UL transmission in LTE or NR. For example, terminal 20 scrambles the codeword of the transmission data, modulates it to generate complex-valued symbols, maps these complex-valued symbols (transmission signal) to one or two layers, and performs precoding. Then, it maps the precoded complex-valued symbols to resource elements to generate a transmission signal (e.g., a complex-valued time-domain SC-FDMA signal) and transmits it from each antenna port.

[0040] The base station 10 has the functionality of a cellular communication base station in LTE or NR, and functions to enable communication for the terminal 20 in this embodiment (e.g., resource pool setting, resource allocation, etc.). The base station 10 may also be an RSU (gNB type RSU).

[0041] Furthermore, in the wireless communication system according to the embodiment of the present invention, the signal waveform used by the terminal 20 for SL or UL may be OFDMA, SC-FDMA, or other signal waveforms.

[0042] In step S101, terminal 20A autonomously selects resources to be used for PSCCH and PSSCH from a resource selection window having a predetermined period. The resource selection window may be set from base station 10 to terminal 20. Here, the predetermined period of the resource selection window may be defined by terminal implementation conditions such as processing time or maximum allowable packet delay time, or it may be defined in advance by specifications, or the predetermined period may be called an interval in the time domain.

[0043] In steps S102 and S103, terminal 20A transmits SCI (Sidelink Control Information) via PSCCH and / or PSSCH using the resources autonomously selected in step S101, and also transmits SL data via PSSCH. For example, terminal 20A may transmit PSCCH using the same time resources as at least a portion of the time resources of PSSCH, and using frequency resources adjacent to the frequency resources of PSSCH.

[0044] Terminal 20B receives SCI (PSCCH and / or PSSCH) and SL data (PSSCH) transmitted from terminal 20A. The received SCI may include information about the PSFCH resource that terminal 20B uses to send a HARQ-ACK for receiving the data. Terminal 20A may also include information about an autonomously selected resource in the SCI and transmit it.

[0045] In step S104, terminal 20B uses the PSFCH resources determined from the received SCI to send a HARQ-ACK for the received data to terminal 20A.

[0046] In step S105, if the HARQ-ACK received in step S104 indicates a request for retransmission, i.e., it is a NACK (negative response), terminal 20A retransmits PSCCH and PSSCH to terminal 20B. Terminal 20A may also retransmit PSCCH and PSSCH using a resource that it has autonomously selected.

[0047] If HARQ control with HARQ feedback is not performed, steps S104 and S105 do not need to be performed.

[0048] Figure 11 is a sequence diagram showing an example of V2X operation (2). Blind retransmission without HARQ control may be performed to improve the transmission success rate or range.

[0049] In step S201, terminal 20A autonomously selects resources to be used for PSCCH and PSSCH from a resource selection window having a predetermined period of time. The resource selection window may be set from base station 10 to terminal 20.

[0050] In steps S202 and S203, terminal 20A transmits SCI via PSCCH and / or PSSCH, and transmits SL data via PSSCH, using the resources autonomously selected in step S201. For example, terminal 20A may transmit PSCCH using the same time resources as at least a portion of the time resources of PSSCH, and using frequency resources adjacent to the frequency resources of PSSCH.

[0051] In step S204, terminal 20A uses the resources autonomously selected in step S201 to retransmit SCI via PSCCH and / or PSSCH and SL data via PSSCH to terminal 20B. The retransmission in step S204 may be performed multiple times.

[0052] If blind retransmission is not performed, step S204 does not need to be executed.

[0053] Figure 12 is a sequence diagram showing an example of V2X operation (3). The base station 10 may perform sidelink scheduling. That is, the base station 10 may determine the sidelink resources to be used by the terminal 20 and transmit information indicating those resources to the terminal 20. Furthermore, if HARQ control with HARQ feedback is applied, the base station 10 may transmit information indicating PSFCH resources to the terminal 20.

[0054] In step S301, base station 10 performs SL scheduling by sending DCI (Downlink Control Information) to terminal 20A via PDCCH. Hereafter, for convenience, the DCI used for SL scheduling will be referred to as SL scheduling DCI.

[0055] Furthermore, in step S301, it is assumed that the base station 10 also transmits a DCI for DL ​​scheduling (which may also be called DL allocation) to the terminal 20A via PDCCH. Hereafter, for convenience, the DCI for DL ​​scheduling will be referred to as DL scheduling DCI. Upon receiving the DL scheduling DCI, the terminal 20A receives DL data via PDSCH using the resources specified in the DL scheduling DCI.

[0056] In steps S302 and S303, terminal 20A transmits SCI (Sidelink Control Information) via PSCCH and / or PSSCH using the resources specified in the SL scheduling DCI, and also transmits SL data via PSSCH. Note that only the resources for PSSCH may be specified in the SL scheduling DCI. In this case, for example, terminal 20A may transmit PSCCH using the same time resources as at least a portion of the time resources for PSSCH, and using frequency resources adjacent to the frequency resources for PSSCH.

[0057] Terminal 20B receives SCI (PSCCH and / or PSSCH) and SL data (PSSCH) transmitted from terminal 20A. The SCI received via PSCCH and / or PSSCH contains information about the PSFCH resource that terminal 20B uses to send a HARQ-ACK for the reception of the data.

[0058] The resource information is included in the DL scheduling DCI or SL scheduling DCI transmitted from the base station 10 in step S301, and the terminal 20A retrieves the resource information from the DL scheduling DCI or SL scheduling DCI and includes it in the SCI. Alternatively, the DCI transmitted from the base station 10 may not include the resource information, and the terminal 20A may autonomously include the resource information in the SCI and transmit it.

[0059] In step S304, terminal 20B uses the PSFCH resources determined from the received SCI to send a HARQ-ACK for the received data to terminal 20A.

[0060] In step S305, terminal 20A transmits a HARQ-ACK using the PUCCH (Physical uplink control channel) resource specified by the DL scheduling DCI (or SL scheduling DCI) at a timing (e.g., a slot-based timing) specified by the DL scheduling DCI (or SL scheduling DCI), and base station 10 receives the HARQ-ACK. The codebook of the HARQ-ACK may include a HARQ-ACK generated based on the HARQ-ACK received from terminal 20B or a PSFCH that was not received, and a HARQ-ACK for DL ​​data. However, if there is no allocation of DL data, the HARQ-ACK for DL ​​data will not be included. In NR Rel.16, the codebook of the HARQ-ACK does not include a HARQ-ACK for DL ​​data.

[0061] If HARQ control with HARQ feedback is not performed, steps S304 and / or S305 may not be performed.

[0062] Figure 13 is a sequence diagram showing an example of V2X operation (4). As mentioned above, in the NR sidelink, it is supported that the HARQ response is transmitted in PSFCH format. The PSFCH format can be the same as, for example, the PUCCH (Physical Uplink Control Channel) format 0. That is, the PSFCH format may be a sequence-based format in which the PRB (Physical Resource Block) size is 1 and ACK and NACK are identified by the difference in sequence and / or cyclic shift. The PSFCH format is not limited to this. The PSFCH resource may be placed in the symbol at the end of the slot or in multiple symbols at the end. In addition, a period N is set or predetermined for the PSFCH resource. The period N may be set or predetermined on a per-slot basis.

[0063] In Figure 13, the vertical axis corresponds to the frequency domain and the horizontal axis corresponds to the time domain. A PSCCH may be placed in the first symbol of a slot, in multiple symbols from the beginning, or in multiple symbols from symbols other than the first. A PSFCH may be placed in the last symbol of a slot, or in multiple symbols at the end of a slot. Note that the above-mentioned "beginning of the slot" and "end of the slot" may omit consideration of symbols for AGC (Automatic Gain Control) and symbols for transmit / receive switching. That is, for example, if one slot consists of 14 symbols, "beginning of the slot" and "end of the slot" may mean the first and last symbols, respectively, among the 12 symbols excluding the first and last symbols. In the example shown in Figure 13, three subchannels are set in the resource pool, and two PSFCHs are placed three slots after the slot in which the PSSCH is placed. The arrow from PSSCH to PSFCH shows an example of a PSFCH associated with a PSSCH.

[0064] If the NR-V2X group cast uses group cast option 2, where the HARQ response is either an ACK or a NACK, it is necessary to determine the resources to be used for sending and receiving PSFCH. As shown in Figure 13, in step S401, the transmitting terminal 20, terminal 20A, performs a group cast via SL-SCH to the receiving terminals 20, terminals 20B, 20C, and 20D. In the following step S402, terminal 20B uses PSFCH#B, terminal 20C uses PSFCH#C, and terminal 20D uses PSFCH#D to send the HARQ response to terminal 20A. Here, as shown in the example in Figure 13, if the number of available PSFCH resources is less than the number of receiving terminals 20 belonging to the group, it is necessary to determine how to allocate the PSFCH resources. The transmitting terminal 20 may also know the number of receiving terminals 20 in the group cast. In group cast option 1, only a NACK is sent as the HARQ response; an ACK is not sent.

[0065] Figure 14 shows an example of sensing operation in NR. In Resource allocation mode 2, terminal 20 selects and transmits a resource. As shown in Figure 14, terminal 20 performs sensing in the sensing window within the resource pool. Through sensing, terminal 20 receives resource reservation or resource assignment fields included in the SCI transmitted from other terminals 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.

[0066] Furthermore, as shown in Figure 14, the resource pool settings may have a period. For example, the period may be a duration of 10240 milliseconds. Figure 14 shows slot t0 SLfrom slot t Tmax-1 SL This is an example where the period from Tmax-1 to SL is set as a resource pool. The resource pool within each period may be set by, for example, a bitmap.

[0067] Also, as shown in FIG. 14, 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 can detect, for example, that another terminal 20 is performing a transmission with priority p proc,0 in the sensing window from slot n - T0 to the slot immediately before slot n - T RX When 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, when 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 and may be such.

[0068] Also, as shown in slot t in FIG. 14 m SL For example, for transmission, the resources within the resource selection window that are candidates for resource reservation information corresponding to the resources within the sensing window that were not monitored are excluded.

[0069] As shown in FIG. 14, for the resource selection window from slot n + T1 to slot n + T2, the resources occupied by other UEs are identified, and the resources after excluding the occupied resources become candidate available resources. Let the set of candidate available resources be S A Then S AIf the resource selection window is less than 20%, the threshold Th is set for each resource in the sensing window. pTX,pRX You can increase the threshold Th by 3dB and perform resource identification again. pTX,pRX By increasing the value and performing resource identification again, the number of resources that are not excluded because the RSRP is below the threshold is increased, resulting in a set of resource candidates S. A 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.

[0070] 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 use the determined resource to perform a sidelink transmission.

[0071] Although Figure 14 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.

[0072] Figure 15 is a flowchart showing an example of preemption in NR. Figure 16 is a diagram showing an example of preemption in NR. In step S501, terminal 20 performs sensing in the sensing window. If terminal 20 is performing power-saving operation, sensing may be performed for a predetermined limited period. Subsequently, terminal 20 identifies each resource in the resource selection window based on the sensing results and selects a set of resource candidates S A The terminal 20 then determines the set of resource candidates S and selects the resource to be used for transmission (S502). ASelect a resource set (r_0, r_1, ...) from which to determine preemption (S503). This resource set may be notified to the PHY layer from the upper layer as a resource to determine whether or not preemption has occurred.

[0073] In step S504, terminal 20, at timings T(r_0)-T3 shown in Figure 16, re-identifies each resource in the resource selection window based on the sensing results and selects a set of resource candidates S. A The system determines this and then determines preemption for the resource set (r_0, r_1, ...) based on priority. For example, in Figure 16, r_1 is detected by resensing as an SCI transmitted from another terminal 20, and S A It is not included in S. If preemption is enabled, terminal 20 determines that resource r_1 has been preempted if the value prio_RX, which indicates the priority of an SCI sent from another terminal 20, is lower than the value prio_TX, which indicates the priority of a transport block sent from its own terminal. Note that a lower value indicates a higher priority. In other words, if the value prio_RX, which indicates the priority of an SCI sent from another terminal 20, is higher than the value prio_TX, which indicates the priority of a transport block sent from its own terminal, terminal 20 determines that resource r_1 has been preempted. A It is not excluded. Alternatively, if preemption is only effective for a specific priority (for example, if sl-PreemptionEnable is one of pl1, pl2, ..., pl8), this priority is set to prio_pre. In this case, if the value prio_RX, which indicates the priority of the SCI sent from another terminal 20, is lower than prio_pre, and prio_RX is lower than the value prio_TX, which indicates the priority of the transport block sent from the terminal itself, terminal 20 determines that resource r_1 has been preempted.

[0074] In step S505, if preemption is determined in step S504, terminal 20 notifies the upper layer of the preemption, the upper layer re-selects the resource, and the preemption check is terminated.

[0075] If re-evaluation is performed instead of preemption checking, in step S504 above, the set of resource candidates S A After deciding, S A If the resource set (r_0, r_1, ...) does not contain any resources, those resources will not be used, and a re-selection of resources will be performed in the higher layer.

[0076] Figure 17 shows an example of partial sensing operation in LTE. When partial sensing is configured from the upper layer in an LTE sidelink, terminal 20 selects and transmits resources as shown in Figure 17. As shown in Figure 17, terminal 20 performs partial sensing on a portion of the sensing window in the resource pool, i.e., the sensing target. Through partial sensing, terminal 20 receives the resource reservation field included in the SCI transmitted from another terminal 20 and identifies available resource candidates in the resource selection window in the resource pool based on this field. Subsequently, terminal 20 randomly selects a resource from the available resource candidates.

[0077] Figure 17 shows subframe t0 SL From subframe t Tmax-1 SL This is an example of setting the resource pool up to this point. The resource pool may also have its target area defined by, for example, a bitmap. As shown in Figure 17, the transmission trigger at terminal 20 is assumed to occur in subframe n. As shown in Figure 17, of the subframes from subframe n+T1 to subframe n+T2, subframe t y1 SL From subframe t yY SLThe Y subframe up to this point may be set as the resource selection window.

[0078] Terminal 20 has a subframe t whose Y subframe length. y1-k×Pstep SL From subframe t yY-k×Pstep SL Up to one or more sensing targets, it is possible to detect, for example, that another terminal 20 is transmitting. k may be determined by, for example, a 10-bit bitmap. Figure 17 shows an example where the 3rd and 6th bits of the bitmap are set to "1" to indicate that partial sensing is being performed. That is, in Figure 17, subframe t y1-6×Pstep SL From subframe t yY-6×Pstep SL up to and subframe t y1-3×Pstep SL From subframe t yY-3×Pstep SL Up to and are set as sensing targets. As described above, the k-th bit of the bitmap is subframe t y1-k×Pstep SL From subframe t yY-k×Pstep SL It may also support a sensing window up to y. i This corresponds to the index (1...Y) within the Y subframe.

[0079] Note that k is set as a 10-bit bitmap or is predetermined, P step It may be 100ms. However, when performing SL communication with DL and UL carriers, P step This can also be expressed as (U / (D+S+U))*100ms, where U is the number of UL subframes, D is the number of DL subframes, and S is the number of special subframes.

[0080] If an SCI is detected in the sensing target and the RSRP exceeds the threshold, the resources in the resource selection window corresponding to the resource reservation field of that SCI are excluded. Conversely, if an SCI is detected in the sensing target and the RSRP is below the threshold, the resources in the resource selection window corresponding to the resource reservation field of that SCI are not excluded. This threshold is, for example, the sender priority p. TX and receiver priority p RX Based on this, thresholds Th are set or defined for each resource within the sensing target. pTX,pRX That's fine.

[0081] As shown in Figure 17, in the resource selection window set in the Y subframe of the interval [n+T1, n+T2], terminal 20 identifies resources occupied by other UEs, and the resources remaining after excluding those resources become the available resource candidates. Note that the Y subframes do not have to be consecutive. The set of available resource candidates is S A Therefore, S A If the number is less than 20% of the resources in the resource selection window, the threshold Th is set for each resource of the sensing target. pTX,pRX You can increase the value by 3dB and perform resource identification again.

[0082] That is, the threshold Th pTX,pRX You may increase the number of resources that are not excluded because their RSRP is below the threshold by raising the value and performing resource identification again. A Measure the RSSI of each resource and set the resource with the smallest RSSI to group S. B It may also be added to the set of resource candidates S. B Until it fills more than 20% of the resource selection window, S A The RSSI included is the smallest resource S B You may repeat the action of adding to it.

[0083] The lower layer of terminal 20 is S B This may be reported to the upper layer. The upper layer of terminal 20 is SB Terminal 20 may perform a random selection to determine which resource to use. Terminal 20 may use the determined resource to perform a sidelink transmission. After securing a resource once, terminal 20 may perform a predetermined number of operations (for example, C resel (This time) Resources may be used periodically without performing sensing.

[0084] Here, in NR Release 17 sidelinks, power saving based on random resource selection and partial sensing is being considered. For example, for power saving purposes, random resource selection and partial sensing in sidelinks in LTE Release 14 may be applied to resource allocation mode 2 of NR Release 16 sidelinks. Terminal 20 to which partial sensing is applied performs reception and sensing only in specific slots within the sensing window.

[0085] Furthermore, in NR Release 17 Sidelink, operation is being considered with inter-UE coordination as the baseline. For example, terminal 20A may share information indicating the resource set with terminal 20B, and terminal 20B may take this information into consideration when selecting resources for transmission.

[0086] For example, as a method of resource allocation in a side link, terminal 20 may perform full sensing as shown in Figure 14. Alternatively, terminal 20 may perform partial sensing, which identifies resources by sensing only a limited set of resources compared to full sensing, and selects resources from the identified resource set. Furthermore, terminal 20 may perform random selection, which identifies the resources in the resource selection window as an identified resource set without excluding any resources from the resources in the resource selection window, and selects resources from that identified resource set.

[0087] Furthermore, at the time of resource selection, a method that performs random selection and uses sensing information during re-evaluation or preemption checks may be treated as partial sensing or as random selection.

[0088] Furthermore, the following operations 1) and 2) may be applied to sensing. Note that sensing and monitoring may be interchangeable, and at least one of the following may be included in the operation: measurement of received RSRP, acquisition of reserved resource information, and acquisition of priority information.

[0089] 1)Periodic-based partial sensing In a system that performs sensing on only some slots, this operation determines which slots to sense based on the reservation periodicity. The reservation period is a value related to the resource reservation period field. Note that "period" may be replaced with "periodicity".

[0090] 2) Contiguous partial sensing In a system where sensing is performed on only a portion of the slots, the sensing slots are determined based on aperiodic reservations. Note that aperiodic reservations are values ​​related to the time resource assignment field.

[0091] Release 17 may define the operation assuming three types of terminals 20. One is type A, and a type A terminal 20 has no ability to receive any sidelink signals and channels, except for receiving PSFCH and S-SSB (SS / PBCH block).

[0092] The other is type B, and terminal 20 of type B does not have the ability to receive any sidelink signals and channels except PSFCH and S-SSB reception.

[0093] The other is Type D, and a Type D terminal 20 has the ability to receive signals and channels of all sidelinks as defined in Release 16, except that it does not exclude receiving signals and channels of some sidelinks.

[0094] Furthermore, UE types other than the above-mentioned types A, B, and D may be assumed, and UE types and UE capabilities may or may not be associated.

[0095] Furthermore, in Release 17, multiple resource allocation methods can be configured for a given resource pool. Additionally, SL-DRX (Discontinuous reception) is supported as a power-saving feature; that is, reception operations are performed only during predetermined time intervals.

[0096] As described above, partial sensing is supported as one of the power saving functions. In a resource pool where partial sensing is configured, terminal 20 may perform the periodic partial sensing described above. Terminal 20 may receive information from base station 10 to configure a resource pool in which partial sensing is configured and periodic reservations are enabled.

[0097] Figure 18 is a diagram illustrating an example of periodic partial sensing. As shown in Figure 18, candidate Y slots for resource selection are selected from the resource selection window [n+T1, n+T2].

[0098] t y SL Let t be one of the slots included in the Y candidate slots. y-k×Preserve SL This can be used as the target slot for periodic partial sensing, and sensing may be performed on it.

[0099] P reserve This may correspond to all values ​​included in the set sl-ResourceReservePeriodList, which is set or predefined. Alternatively, it may correspond to P, which is limited to a subset of sl-ResourceReservePeriodList. reserve The value of P may be set or predetermined. reserve The sl-ResourceReservePeriodList may also be set for each transmit resource pool in resource allocation mode 2. Additionally, the UE implementation may monitor periods included in the sl-ResourceReservePeriodList other than a limited subset. For example, terminal 20 may additionally monitor opportunities corresponding to P_RSVP_Tx.

[0100] With respect to the k value, terminal 20 may monitor the most recent sensing opportunity in a certain reservation cycle prior to slot n of the resource selection trigger, or prior to the first slot of the Y candidate slots subject to processing time limitations. Terminal 20 may also additionally monitor periodic sensing opportunities corresponding to a set of 1 or more k values. For example, the k value may be set to a value corresponding to the most recent sensing opportunity in a certain reservation cycle prior to slot n of the resource selection trigger, or prior to the first slot of the Y candidate slots subject to processing time limitations, and a value corresponding to the sensing opportunity immediately preceding the most recent sensing opportunity in that reservation cycle.

[0101] As described above, partial sensing is supported as one of the power-saving functions. In a resource pool where partial sensing is configured, terminal 20 may perform the continuous partial sensing described above. Terminal 20 may receive information from base station 10 to configure a resource pool in which partial sensing is configured and aperiodic reservations are enabled.

[0102] Figure 19 is a diagram illustrating an example of continuous partial sensing. As shown in Figure 19, when the trigger for resource selection is slot n, terminal 20 selects a Y candidate slot for resource selection from the resource selection window [n+T1, n+T2]. Figure 19 is an example for the case where Y=7. As shown in Figure 19, the beginning of the Y candidate slot is slot t y1 And the next slot is t y2 And, ..., the end of the candidate slot Y is slot t yY This is how it is written.

[0103] Terminal 20 is in the section [n+T A ,n+T B Sensing is performed at ], n+T B or n+T B After (n+T C Resource selection is performed in the interval [n+T]. Note that the periodic partial sensing described above may be performed additionally. A ,n+T B ] of T A and T B n can be any value. Also, n may be replaced with the index of any of the candidate slots in Y.

[0104] Furthermore, the symbol [ may be replaced with the symbol (and the symbol ] may be replaced with the symbol ). For example, the interval [a,b] is the interval from slot a to slot b, and includes both slot a and slot b. For example, the interval (a,b) is the interval from slot a to slot b, and does not include both slot a and slot b.

[0105] Note that the candidate resources that are the target of resource selection are referred to as Y candidate slots, but all slots in the interval [n+T1, n+T2] may be candidate slots, or some of the slots may be candidate slots.

[0106] In 3GPP Release 16, the initial specifications for NR sidelinks were defined. Based on LTE-SL, these specifications adhere to the NR concept and are designed for V2X. These specifications support features such as aperiodic and / or periodic transmission, unicast and groupcast, HARQ feedback, 256QAM (Quadrature amplitude modulation), MIMO (Multiple input multiple output), CSI (Channel state information) reporting, single-carrier transmission, and FR1 (Frequency Range 1).

[0107] Furthermore, 3GPP Release 17 is considering an extended specification for NR sidelinks from Release 16. This specification addresses use cases such as public safety communications and commercial communications in addition to V2X, and explores features related to power-saving operation, reliability, and latency performance improvements. For example, for power-saving operation, partial sensing, random selection of resources used for transmission, and DRX are being considered. For example, for reliability and latency performance improvements, inter-UE coordination is being considered.

[0108] Furthermore, 3GPP Release 18 is considering further enhanced specifications for NR sidelinks. These specifications may include improvements to data rates, support for new frequencies, and the addition of V2X extensions. Potential additional features being considered include sidelink carrier aggregation, support for unlicensed bands, support for FR2, beam management, and LTE-SL and NR-SL channel coexistence systems.

[0109] In LTE-SL carrier aggregation, synchronization is performed by all carriers referencing a specific carrier. The carrier referenced for synchronization can be any of the carrier sets configured at the higher layer.

[0110] Furthermore, in LTE-SL, resource selection in carrier aggregation may be performed by including a carrier indicator in the SCI when scheduling is performed by the base station 10. Also, when the UE autonomously selects resources, a carrier may be selected for each resource selection. For example, a carrier may be selected based on the priority of the logical channel or the CBR (Channel busy ratio). For example, one carrier may be used for each resource selection. For example, one carrier may be used for the transmission of a certain transport block. For example, after selecting a carrier, an independent resource selection procedure may be performed for each carrier. For example, resources that cannot be transmitted simultaneously may be excluded as the final step of resource identification (i.e., after operations related to resource exclusion based on reservation signals received from other terminals 20). For example, resources that cannot be transmitted simultaneously may be excluded based on the number of simultaneous transmissions, supported carrier combinations, and processing time.

[0111] Furthermore, regarding power control in carrier aggregation in LTE-SL, power may be reduced based on priority to avoid exceeding the maximum transmission power, or transmission may be omitted altogether. In addition, packet duplication may be performed in carrier aggregation in LTE-SL.

[0112] Here, it is necessary to determine the operation when performing carrier aggregation in NR-SL. For example, applying the same operation as in LTE-SL may not meet the required quality. Also, it may not be possible to support new features introduced in NR that do not exist in LTE. Note that carrier aggregation may also mean a function that transmits or receives through multiple carriers within the same time unit.

[0113] Therefore, in NR-SL, the following carrier aggregation operations may be performed.

[0114] 1) When terminal 20 performs carrier aggregation in SL, it may select a carrier as shown in at least one of 1A)-1G) below.

[0115] 1A) Terminal 20 may select a carrier based on at least one of the following: information related to SL-HARQ feedback (e.g., PSFCH resources), priority, periodic reservation, sensing method, IUC (Inter UE coordination), CBR, RSRP threshold (e.g., RSRP threshold for resource exclusion related to resource selection), MCS (Modulation and Coding Scheme) table, and the capabilities of the destination UE.

[0116] 1B) Terminal 20 may select a carrier as a candidate based on the priority of the transmitted data and the carrier's CBR. For example, terminal 20 may compare the CBR threshold related to the priority of the transmitted data with the carrier's CBR and select a carrier as a candidate if the carrier's CBR does not exceed the CBR threshold.

[0117] 1C) When terminal 20 performs carrier selection for the transmission of data requiring SL-HARQ feedback (hereinafter, "data" may be any of the following: transport block, MAC-PDU (Protocol data unit), MAC-SDU (Service data unit), logical channel, etc., and may also be information transmitted via PSSCH), it may select a carrier that includes a PSFCH resource that is configured or a pre-configured resource pool as a candidate for selection.

[0118] Figure 20 is a diagram illustrating an example (1) of carrier selection in an embodiment of the present invention. As shown in Figure 20, carrier a includes resource pool a-1 in which PSFCH resources are configured, and carrier b includes resource pool b-1 in which PSFCH resource pools are configured. Therefore, terminal 20 may select carrier a and carrier b as candidates for carrier selection.

[0119] For example, if the information element sl-HARQ-FeedbackEnabled is enabled for the logical channel, the MAC entity may select one or more carriers that include at least one resource pool in which the PSFCH resource is configured.

[0120] By operating as described above, it is possible to avoid selecting carriers for which PSFCH resources are not configured for data that requires SL-HARQ feedback.

[0121] 1D) Terminal 20 has a periodic reservation (e.g., P rsvp_TX When performing carrier selection for the transmission of data that requires a non-zero value, the terminal 20 may select a carrier that includes a resource pool in which the allowed reservation periodicity (e.g., sl-ResourceReservePeriodList) has a non-zero value (see Non-Patent Literature 3). For example, the terminal 20 may select a carrier that includes a resource pool in the list of allowed reservation periods (sl-ResourceReservePeriodList) that has a predetermined reservation period (SL-ResourceReservePeriod) value (see Non-Patent Literature 4). For example, the predetermined reservation period may be the reservation period required for the transmission of the corresponding data. By operating in this manner, the terminal can ensure that data transmission is performed reliably when performing data transmission involving periodic reservations. Note that period and periodicity may be read interchangeably.

[0122] 1E) When terminal 20 performs carrier selection for data transmission based on a predetermined sensing method and / or resource selection method, it may select carriers that include resource pools for which the sensing method and / or resource selection method is set or pre-set as selection candidates. For example, terminal 20 may select carriers that include resource pools for which no method other than the predetermined sensing method and / or resource selection method is provided as selection candidates. For example, for data transmission requiring high reliability and / or low latency, terminal 20 may exclude carriers that include resource pools for which only full sensing is permitted and partial sensing or random selection is not permitted from the selection candidates. By operating in this manner, terminal 20 can select a carrier for which the desired sensing and / or resource selection method is available.

[0123] 1F) When terminal 20 performs carrier selection for the transmission of data to be sent on a resource pool capable of running IUC, it may select a carrier that includes a resource pool where IUC is configured or pre-configured as a candidate for selection. By operating in this manner, terminal 20 can transmit data requiring high reliability and / or low latency performance on a resource pool capable of running IUC.

[0124] 1G) When terminal 20 performs carrier selection for transmitting data using a predetermined MCS table, it may select a carrier that includes a resource pool in which the MCS table is set or pre-configured as a candidate for selection. By operating in this manner, terminal 20 can select a carrier that has the desired MCS table available.

[0125] 1H) When performing career selection based on multiple elements from among the elements described in 1A) above, the career selection may be performed by applying the multiple elements in a predetermined priority and / or order. For example, they may be applied in the order shown below.

[0126] 1) The capabilities of Destination UE in each career 2) Information related to SL-HARQ feedback (e.g., PSFCH resources) 3) Sensing and / or resource selection method 4) Priority of transmitted data and carrier CBR 5) Periodic booking 6) IUC and / or RSRP thresholds and / or MCS tables

[0127] Some of the elements from 1)-6) above may be applied. For example, only the top X elements may be applied. The elements from 1)-6) above may be applied in order from top to bottom, and elements below a predetermined value may not be applied based on a predetermined condition (e.g., the number of candidate carriers). For example, if the number of candidate carriers reaches or falls below a predetermined value, elements below a predetermined value may not be applied based on a predetermined condition.

[0128] Note that the rankings shown in 1)-6) above are examples, and any other rankings may be set.

[0129] By operating as described above, device 20 can make a carrier selection based on more important factors.

[0130] 2) When terminal 20 performs carrier aggregation in SL, it may perform a re-evaluation and / or preemption check as shown in at least one of 2A)-2G) below. The preemption check may be replaced with preemption. Hereinafter, "re-evaluation and / or preemption check" will be referred to as "re-evaluation / preemption check".

[0131] 2A) If the resources subject to re-evaluation / preemption check reside on a single carrier, terminal 20 may perform the re-evaluation / preemption check considering only that carrier. For example, terminal 20 may not need to apply resource exclusion related to at least one of the following: the number of simultaneous transmissions, supported carrier combinations, or processing time for simultaneous transmissions. By operating in this manner, the re-evaluation / preemption check can behave similarly to that in non-carrier aggregation cases, preventing the process from becoming overly complex.

[0132] 2B) If the resource subject to the re-evaluation / preemption check exists on a single carrier, terminal 20 may perform the re-evaluation / preemption check considering multiple carriers. For example, if a resource selected or reserved by each carrier overlaps with a resource selected or reserved by another carrier, and it is determined that the resource cannot be used for transmission due to at least one of the following factors: the number of simultaneous transmissions, the supported carrier combinations, or the processing time for simultaneous transmissions, a re-evaluation / preemption check may be notified from the PHY to the MAC. "A re-evaluation / preemption check is notified from the PHY to the MAC" may mean that a notification indicating that the resource is unavailable or needs to be re-selected is sent from the PHY to the MAC in the UE. That is, the notification may be a trigger to stop using the resource and perform re-selection at the MAC layer.

[0133] 2C) If the resource subject to re-evaluation / preemption check exists on multiple carriers, terminal 20 may perform the re-evaluation / preemption check on each carrier. The existence of a target resource on multiple carriers means, for example, that the target resource includes resource #A and resource #B, and resource #A exists on carrier a and resource #B exists on carrier b.

[0134] If a resource subject to re-evaluation / preemption check exists across multiple carriers, for example, if a re-evaluation / preemption check is notified from the PHY to the MAC for a resource on a particular carrier, the terminal 20 may perform a re-selection without using that resource on that carrier.

[0135] If a resource subject to re-evaluation / preemption check exists across multiple carriers, for example, if a re-evaluation / preemption check is notified from the PHY to the MAC for a resource on a particular carrier, the terminal 20 may perform a re-selection without using any of the resources on any carrier (i.e., any of the carriers).

[0136] By operating as described above, the re-evaluation / preemption checks behave the same way as in non-carrier aggregation, preventing the process from becoming overly complex.

[0137] 2D) If a resource subject to re-evaluation / preemption check exists on multiple carriers, the MAC layer may perform resource re-selection in the resource pool containing the target resource. This action allows for immediate re-selection from resources for which resource identification has already been performed.

[0138] 2E) If a resource subject to re-evaluation / preemption check exists on multiple carriers, the MAC layer may perform resource re-selection on the same carrier as the target resource. This action eliminates the need to re-execute carrier selection, simplifying UE operation.

[0139] 2F) If the resources subject to re-evaluation / preemption checks are on multiple carriers, the MAC layer may perform carrier selection again and re-select the resources on the selected carrier. Alternatively, it may perform carrier selection by applying one of the methods described in 1) above. This action allows the best carrier to be selected when performing re-evaluation / preemption checks, improving reliability.

[0140] Figure 21 is a diagram illustrating an example (2) of carrier selection in an embodiment of the present invention. "Re-selection 1" shown in Figure 21 shows a carrier selection corresponding to 2D) above. That is, when the target resource for re-evaluation / preemption check exists on multiple carriers, this is an example in which the MAC layer performs resource re-selection in the resource pool containing the target resource. "Re-selection 2" shown in Figure 21 shows a carrier selection corresponding to 2E) above. That is, this is an example in which the MAC layer performs resource re-selection on the same carrier as the target resource. "Re-selection 3" shown in Figure 21 shows a carrier selection corresponding to 2F) above. That is, this is an example in which the MAC layer performs carrier selection again and performs resource re-selection on the selected carrier.

[0141] 2G) Terminal 20 may switch which of the above 2D), 2E), and 2F) to apply based on predetermined conditions. For example, terminal 20 may switch which of the above 2D), 2E), and 2F) to apply based on the conditions shown in 1)-5) below.

[0142] 1) Whether the resources subject to reassessment / preemption checks are located on multiple carriers or on a single carrier. 2) Whether the RSRP threshold or CBR for re-evaluation / preemption checks exceeds a predetermined value in the resource pool that includes the resources subject to re-evaluation / preemption checks. 3) Whether the RSRP threshold or CBR for reassessment / preemption checks exceeds a predetermined value in the carrier that includes the resources subject to reassessment / preemption checks. 4) Whether a reassessment was notified or a preemption check was notified. 5) Whether the resources subject to re-evaluation / preemption check are already reserved (as indicated in SCI)

[0143] By operating as described above, terminal 20 can apply the most appropriate resource reselection method depending on the situation.

[0144] In the above embodiment, the carrier may be replaced with a CC (Component Carrier), a cell, a serving cell, a resource pool, etc.

[0145] The above-described embodiment may be applied to an operation in which one terminal 20 sets or allocates transmission resources for another terminal 20.

[0146] The above-described embodiment is not limited to V2X terminals, but may also be applied to terminals that perform D2D communication.

[0147] The operations described in the above embodiment may be executed only in specific resource pools. For example, they may be executed only in resource pools where terminal 20 is available for release 17 or later, or release 18 or later.

[0148] In the above embodiment, in a side link to which carrier aggregation is applied, terminal 20 can perform carrier selection and resource re-evaluation / preemption checks as needed.

[0149] In other words, carrier aggregation can be used for direct communication between terminals.

[0150] (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.

[0151] <Base station 10> Figure 22 is a diagram showing an example of the functional configuration of the base station 10. As shown in Figure 22, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Figure 22 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.

[0152] 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.

[0153] 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.

[0154] 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.

[0155] <Terminal 20> Figure 23 is a diagram showing an example of the functional configuration of terminal 20. As shown in Figure 23, 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 23 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.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] (Hardware configuration) The block diagrams (Figures 22 and 23) 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.

[0160] 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.

[0161] 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 24 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.

[0162] In the following explanation, the term "device" can be replaced with "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.

[0163] 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.

[0164] 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.

[0165] 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 22 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 23 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Although the above-described processes have been explained 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 also be transmitted from the network via a telecommunications line.

[0166] 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.

[0167] 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.

[0168] 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.

[0169] 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).

[0170] 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.

[0171] 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.

[0172] Figure 25 shows an example of the configuration of vehicle 2001. As shown in Figure 25, vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. Each aspect / embodiment described in this disclosure may be applied to a communication device mounted on vehicle 2001, for example, to the communication module 2013.

[0173] 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.

[0174] 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).

[0175] 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.

[0176] 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.

[0177] 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.

[0178] 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.

[0179] 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.

[0180] 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.

[0181] 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.

[0182] (Summary of the embodiments) As described above, according to an embodiment of the present invention, a terminal is provided which includes a communication unit that performs communication to which carrier aggregation is applied with other terminals, and a control unit that performs at least one of the following: carrier selection related to the communication and re-evaluation or preemption check related to the communication, wherein the control unit selects a carrier that includes a resource pool that satisfies certain conditions.

[0183] With the above configuration, in a side link where carrier aggregation is applied, terminal 20 can perform carrier selection and resource re-evaluation / preemption checks as needed. In other words, communication using carrier aggregation can be performed in direct communication between terminals.

[0184] The control unit may select a carrier that includes a resource pool on which a feedback channel is set. With this configuration, in a side link to which carrier aggregation is applied, terminal 20 can perform carrier selection on a situational basis.

[0185] The control unit may select a carrier that includes a resource pool in which a certain permitted reservation cycle is set. With this configuration, in a side link to which carrier aggregation is applied, terminal 20 can perform carrier selection on a situational basis.

[0186] The control unit may apply at least one of the following conditions 1)-6) in a certain priority order when selecting a carrier that satisfies at least one of the following conditions 1)-6). With this configuration, in a side link to which carrier aggregation is applied, the terminal 20 can perform carrier selection according to the situation. 1) Capabilities of Destination UE (User Equipment) in each carrier 2) Information related to Sidelink HARQ feedback 3) Sensing and / or resource selection method 4) Priority of transmitted data and carrier CBR 5) Periodic booking 6) At least one of the following: IUC (inter-UE coordination), RSRP (Reference Signal Received Power) threshold, and MCS (Modulation and Coding Scheme) table.

[0187] The control unit may, in the event of re-evaluation or preemption check when the target resource is located on multiple carriers, perform one of the following: re-selection of a resource in the resource pool containing the target resource, re-selection of a resource on the same carrier as the target resource, or re-selection of a carrier and re-selection of a resource on the selected carrier. With this configuration, in a side link to which carrier aggregation is applied, terminal 20 can perform resource re-evaluation / preemption checks as needed.

[0188] Furthermore, according to embodiments of the present invention, a communication method is provided in which a terminal performs a communication procedure to perform communication to which carrier aggregation is applied with another terminal, a control procedure to perform at least one of carrier selection related to the communication and re-evaluation or preemption check related to the communication, and a procedure to select a carrier that includes a resource pool that satisfies certain conditions.

[0189] With the above configuration, in a side link where carrier aggregation is applied, terminal 20 can perform carrier selection and resource re-evaluation / preemption checks as needed. In other words, communication using carrier aggregation can be performed in direct communication between terminals.

[0190] (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.

[0191] 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.

[0192] 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).

[0193] 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.

[0194] 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).

[0195] 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.

[0196] 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.

[0197] 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).

[0198] 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.

[0199] 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.

[0200] 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.

[0201] 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.

[0202] The terms “system” and “network” as used in this disclosure are interchangeable.

[0203] 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.

[0204] 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.

[0205] 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.

[0206] A base station can accommodate one or more (e.g., three) cells. If a base station accommodates 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.

[0207] In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.

[0208] 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.

[0209] 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.

[0210] 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.

[0211] 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.

[0212] 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, inquiry (e.g., searching in a table, database, or other data structure), and ascertaining. “Determining” may also include, for example, receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, and 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."

[0213] 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.

[0214] The reference signal can also be abbreviated as RS (Reference Signal), and may be called a pilot depending on the applicable standard.

[0215] 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."

[0216] 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.

[0217] In the configuration of each of the above devices, "means" may be replaced with "part," "circuit," "device," etc.

[0218] 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.

[0219] 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.

[0220] 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.

[0221] 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.

[0222] 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.

[0223] 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.

[0224] 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.

[0225] 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.

[0226] 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.

[0227] 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.

[0228] 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.

[0229] 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.

[0230] 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.

[0231] Also, the time domain of the RB may include one or more symbols, and may have a length of 1 slot, 1 mini-slot, 1 sub-frame, or 1 TTI. 1 TTI, 1 sub-frame, etc. may each be composed of one or more resource blocks.

[0232] 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.

[0233] Also, the resource block may be composed of one or more resource elements (REs). For example, 1 RE may be a radio resource area of 1 sub-carrier and 1 symbol.

[0234] The 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. The PRB is defined in a certain BWP and may be numbered within the BWP.

[0235] The BWP may include a BWP for UL (UL BWP) and a BWP for DL (DL BWP). One or more BWPs may be set within one carrier for the terminal 2

[0236] 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".

[0237] The structures such as the above-described radio frames, sub-frames, slots, mini-slots, and symbols are merely exemplary. For example, the number of sub-frames included in a radio frame, the number of slots per sub-frame or radio frame, the number of mini-slots included in a slot, the number of symbols and RBs included in a slot or mini-slot, the number of sub-carriers included in an RB, and the number of symbols within a TTI, symbol length, cyclic prefix (CP) length, etc. can be variously changed.

[0238] In the present disclosure, for example, when articles are added by translation, such as a, an, and the in English, the present disclosure may include that the nouns following these articles are in the plural form.

[0239] In the present disclosure, the term "A and B are different" may mean that "A and B are different from each other". Note that the term may also mean that "A and B are each different from C". Terms such as "separate", "coupled", etc. may also be interpreted in the same way as "different".

[0240] In the present disclosure, each aspect / embodiment described may be used alone, in combination, or switched and used during execution. Also, the notification of predetermined information (for example, the notification of "being X") is not limited to being explicitly performed, and may be performed implicitly (for example, without performing the notification of the predetermined information).

[0241] As described above in detail, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure can be implemented as modified and changed aspects without departing from the spirit and scope of the present disclosure defined by the claims. Therefore, the description of the present disclosure is for the purpose of illustrative explanation and has no restrictive meaning for the present disclosure.

[0242] <Note> (Additional note 1) A communication unit that performs communication with other terminals to apply carrier aggregation, The control unit has a carrier selection function related to the aforementioned communication and a control unit that performs at least one of the following: re-evaluation or preemption check related to the aforementioned communication. The control unit is a terminal that selects a carrier that includes a resource pool that satisfies certain conditions. (Additional note 2) The control unit is the terminal according to Appendix 1, which selects a carrier including a resource pool on which a feedback channel is set. (Additional note 3) The control unit is the terminal according to Appendix 1, which selects a carrier that includes a resource pool in which a certain permitted reservation period is set. (Additional note 4) The terminal described in Appendix 1, wherein the control unit applies at least one of the following conditions 1)-6) in a certain priority order when selecting a carrier that satisfies at least one of the following conditions 1)-6). 1) Capabilities of Destination UE (User Equipment) in each carrier 2) Information related to Sidelink HARQ feedback 3) Sensing and / or resource selection method 4) Priority of transmitted data and carrier CBR 5) Periodic booking 6) At least one of the following: IUC (inter-UE coordination), RSRP (Reference Signal Received Power) threshold, and MCS (Modulation and Coding Scheme) table. (Additional note 5) The control unit is a terminal as described in Appendix 1, which, in the case of re-evaluation or preemption check when the target resource is on multiple carriers, performs one of the following: re-selection of a resource in the resource pool containing the target resource, re-selection of a resource on the same carrier as the target resource, or re-executes carrier selection and re-selects a resource on the selected carrier. (Supplementary Note 6) A communication procedure for performing communication with other terminals by applying carrier aggregation, and A control procedure for performing at least one of carrier selection related to the communication and re-evaluation or preemption check related to the communication, and A communication method in which a terminal executes a procedure for selecting a carrier including a resource pool that satisfies certain conditions.

Explanation of Signs

[0243] 10 Base station 110 Transmission unit 120 Reception unit 130 Setting unit 140 Control unit 20 Terminal 210 Transmission unit 220 Reception unit 230 Setting unit 240 Control unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device 2001 Vehicle 2002 Driving unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever <00​​​​​​​​​​​​​​​​​​​​​​ 2027 Shift lever sensor 2028 Object Detection Sensor 2029 Accelerator pedal sensor 2030 Driver Support Systems Department 2031 Microprocessor 2032 memory (ROM, RAM) 2033 Communication port (I / O port)

Claims

1. A control unit selects a target carrier and the resource pool associated with that target carrier based on the Channel Busy Ratio (CBR) and the priority of the sidelink logical channel when selecting a carrier for transmitting sidelink data. A transmitting unit that performs transmissions in sidelink communication via multiple selected carriers within the same time unit, A terminal equipped with the following features.

2. The control unit selects the target carrier and the resource pool associated with the target carrier if the target carrier's CBR is lower than a threshold related to the priority of the side link logical channel. The terminal according to claim 1.

3. When the control unit selects a carrier for transmitting data that requires feedback, it selects a resource pool in which the resources for the feedback channel are configured. The terminal according to claim 1.

4. The control unit, when the information element sl-HARQ-FeedbackEnabled is set to enabled for the logical channel corresponding to the data, selects the resource pool in which the feedback channel's resource pool is configured. The terminal according to claim 1.

5. When selecting a carrier for transmitting sidelink data, the steps include selecting the target carrier and the resource pool associated with that target carrier based on the Channel Busy Ratio (CBR) and the priority of the sidelink logical channel of the target carrier, The steps include: performing transmissions in sidelink communication via multiple selected carriers within the same time unit; A communication method using a terminal equipped with the following features.

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