Terminal and communication method

Abstract

A terminal and a communication method. A terminal is provided with: a reception unit that receives, from a base station, information for scheduling a first resource for direct communication between terminals, information for scheduling a second resource for communication with the base station, and data via the second resource; and a transmission unit that transmits data to another terminal using the first resource, the reception unit receives a first response relating to retransmission control corresponding to the transmitted data from the other terminal, and the terminal further comprises a control unit that controls the retransmission control according to the transmitted data. And a control unit that determines a third response relating to retransmission control on the basis of the first response and a second response relating to retransmission control corresponding to data via the second resource, the transmission unit transmitting the third response to a base station.

Description

[0001] This application is a divisional application of the invention patent application with application date of August 21, 2020, application number 202080058547.0, and invention name “Terminal and Communication Method”. Technical Field

[0002] The present invention relates to a terminal and a communication method in a wireless communication system. Background Art

[0003] In LTE (Long Term Evolution) and LTE's successor systems (e.g., LTE-A (LTE Advanced), NR (New Radio) (also known as 5G)), D2D (Device to Device) technology is being studied for direct communication between terminals without going through a base station (e.g., non-patent document 1).

[0004] D2D reduces the traffic between the terminal and the base station, and enables communication between the terminals even when the base station cannot communicate during disasters. In addition, in 3GPP (3rd Generation Partnership Project), D2D is called "sidelink", but in this specification, a more general term, D2D, is used. However, in the description of the implementation methods described later, sidelink is also used as needed.

[0005] D2D communication is roughly divided into D2D discovery (also called D2D discovery) for discovering other terminals that can communicate, and D2D communication (also called D2D direct communication, D2D communication, direct communication between terminals, etc.) for direct communication between terminals. Hereinafter, when D2D communication (D2D communication), D2D discovery (D2D discovery), etc. are not specifically distinguished, they are referred to as D2D for short. In addition, signals sent and received via D2D are referred to as D2D signals. Various use cases for services related to V2X (Vehicle to Everything) in NR are being studied (e.g., Non-Patent Document 2).

[0006] Prior art literature

[0007] Non-patent literature

[0008] Non-patent document 1: 3GPP TS 36.211 V15.6.0 (2019-06)

[0009] Non-patent document 2: 3GPP TR 22.886 V15.1.0 (2017-03) Summary of the invention

[0010] Problems to be solved by the invention

[0011] In the inter-terminal direct communication in NR-V2X, support for HARQ (Hybrid automatic repeat request) control is being studied. On the other hand, the method for notifying the base station of information related to the HARQ response of the inter-terminal direct communication and the HARQ response of the downlink from the terminal that has sent the inter-terminal direct communication is not yet clear.

[0012] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to appropriately perform retransmission control in inter-terminal direct communication.

[0013] Means for solving problems

[0014] According to the disclosed technology, a terminal is provided, which comprises: a receiving unit, which receives from a base station information on a first resource scheduled for direct communication between terminals, information on a second resource scheduled for communication with the base station, and data via the second resource; and a sending unit, which uses the first resource to send data to other terminals, the receiving unit receives from the other terminals a first response related to retransmission control corresponding to the sent data, the terminal also comprises a control unit, which determines a third response related to retransmission control based on the first response and a second response related to retransmission control corresponding to the data via the second resource, and the sending unit sends the third response to the base station.

[0015] Effects of the Invention

[0016] According to the disclosed technology, retransmission control can be appropriately performed in inter-terminal direct communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a diagram for explaining V2X.

[0018] Figure 2 This is a diagram for explaining example (1) of the V2X transmission mode.

[0019] Figure 3 This is a diagram for explaining example (2) of the V2X transmission mode.

[0020] Figure 4 This is a diagram for explaining example (3) of the V2X transmission mode.

[0021] Figure 5This is a diagram for explaining example (4) of the V2X transmission mode.

[0022] Figure 6 This is a diagram for explaining example (5) of the V2X transmission mode.

[0023] Figure 7 This is a diagram for explaining example (1) of the V2X communication type.

[0024] Figure 8 This is a diagram for explaining example (2) of the V2X communication type.

[0025] Fig. 9 This is a diagram for explaining example (3) of the V2X communication type.

[0026] Fig.10 This is a diagram showing the configuration and operation (1) of a wireless communication system in an embodiment of the present invention.

[0027] Fig.11 This is a diagram showing an example of transmitting a HARQ-ACK codebook.

[0028] Fig.12 This is a diagram showing an example of the order of HARQ-ACK.

[0029] Fig.13 This is a diagram for explaining DAI.

[0030] Fig.14 This is a diagram showing the configuration and operation (2) of the wireless communication system in the embodiment of the present invention.

[0031] Fig.15 It is a diagram showing an example of the functional configuration of the base station 10 in the embodiment of the present invention.

[0032] Fig.16 This is a diagram showing an example of the functional configuration of the terminal 20 in the embodiment of the present invention.

[0033] Fig.17 This is a diagram showing an example of the hardware configuration of the base station 10 or the terminal 20 in the embodiment of the present invention. DETAILED DESCRIPTION

[0034] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the embodiment described below is only an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0035] When the wireless communication system of the embodiment of the present invention is operated, the existing technology is appropriately used. However, the existing technology is, for example, the existing LTE, but is not limited to the existing LTE. In addition, unless otherwise specified, the term "LTE" used in this specification has a broad meaning including LTE-Advanced and methods after LTE-Advanced (for example, NR) or wireless LAN (Local Area Network: local area network).

[0036] Furthermore, in the embodiments of the present invention, the duplexing method may be a TDD (Time Division Duplex) method, an FDD (Frequency Division Duplex) method, or other methods (for example, Flexible Duplex, etc.).

[0037] In the embodiment of the present invention, “configuring” wireless parameters and the like may be pre-configuring predetermined values, or may be configuring wireless parameters notified from the base station 10 or the terminal 20 .

[0038] Figure 1 This is a diagram for explaining V2X. In 3GPP, the technology to realize V2X (Vehicle to Everything) or eV2X (enhanced V2X) by extending D2D functions is being studied and standardized. Figure 1 As shown, V2X is a part of ITS (Intelligent Transport Systems), which is a general term for V2V (Vehicle to Vehicle) which represents the communication between vehicles, V2I (Vehicle to Infrastructure) which represents the communication between vehicles and roadside units (RSU: Road-Side Unit) installed next to the road, V2N (Vehicle to Network) which represents the communication between vehicles and ITS servers, and V2P (Vehicle to Pedestrian) which represents the communication between vehicles and mobile terminals held by pedestrians.

[0039] In addition, 3GPP is studying V2X that uses cellular communication and terminal-to-terminal communication using LTE or NR. V2X that uses cellular communication is also called cellular V2X. In NR's V2X, research is underway to achieve large capacity, low latency, high reliability, and QoS (Quality of Service) control.

[0040] Regarding LTE or NR V2X, it is envisioned that research not limited to 3GPP specifications will be promoted in the future. For example, it is envisioned that research will be conducted to ensure interoperability, reduce costs caused by high-level installation, use or switch methods of multiple RATs (Radio Access Technology), support for regulations in various countries, and data acquisition, publication, database management and use methods of LTE or NR V2X platforms.

[0041] In the embodiments of the present invention, it is mainly envisioned that the communication device is mounted on a vehicle, but the embodiments of the present invention are not limited to this method. For example, the communication device can be a terminal held by a person, the communication device can also be a device mounted on a drone or an aircraft, the communication device can also be a base station, RSU, relay station (Relay Node), a terminal with scheduling capabilities, etc.

[0042] In addition, SL (Sidelink) can also be distinguished by UL (Uplink) or DL ​​(Downlink) and any one or a combination of the following 1) to 4). In addition, SL can also be other names.

[0043] 1) Resource allocation in the time domain

[0044] 2) Resource allocation in the frequency domain

[0045] 3) Reference synchronization signal (including SLSS (Sidelink Synchronization Signal))

[0046] 4) Reference signal used in path loss measurement for transmit power control

[0047] In addition, for the OFDM (Orthogonal Frequency Division Multiplexing) of SL or UL, any one of CP-OFDM (Cyclic-Prefix OFDM), DFT-S-OFDM (Discrete Fourier Transform-Spread-OFDM), OFDM without transform precoding, or OFDM with transform precoding can also be used.

[0048] In the SL of LTE, Mode 3 and Mode 4 are specified for resource allocation of the SL to the terminal 20. In Mode 3, transmission resources are dynamically allocated using DCI (Downlink Control Information) sent from the base station 10 to the terminal 20. In addition, in Mode 3, SPS (Semi Persistent Scheduling) can also be performed. In Mode 4, the terminal 20 autonomously selects transmission resources from the resource pool.

[0049] In addition, the time slot in the embodiment of the present invention may also be replaced by a symbol, a mini-time slot, a subframe, a radio frame, or a TTI (Transmission Time Interval). In addition, the cell in the embodiment of the present invention may also be replaced by a cell group, a carrier component, a BWP, a resource pool, a resource, a RAT (Radio Access Technology), a system (including a wireless LAN), etc.

[0050] Figure 2 This is a diagram for explaining example (1) of the V2X transmission mode. Figure 2 In the transmission mode of the sidelink communication shown in FIG. 1 , in step 1, the base station 10 sends the scheduling information of the sidelink to the terminal 20A. Then, the terminal 20A sends the PSCCH (Physical Sidelink Control Channel) and PSSCH (Physical Sidelink Shared Channel) to the terminal 20B according to the received scheduling information (step 2). Figure 2The transmission mode of the sidelink communication shown is called the sidelink transmission mode 3 in LTE. In the sidelink transmission mode 3 in LTE, the sidelink scheduling based on Uu is performed. Uu refers to the wireless interface between UTRAN (Universal Terrestrial Radio Access Network) and UE (User Equipment). Figure 2 The transmission mode of the sidelink communication shown is called sidelink transmission mode 1 in NR.

[0051] Figure 3 This is a diagram for explaining example (2) of the V2X transmission mode. Figure 3 In the transmission mode of the side link communication shown in FIG. 1 , the terminal 20A transmits the PSCCH and PSSCH to the terminal 20B using the resources selected autonomously. Figure 3 The transmission mode of the sidelink communication shown is called sidelink transmission mode 4 in LTE. In sidelink transmission mode 4 in LTE, the UE performs the resource selection itself.

[0052] Figure 4 This is a diagram for explaining example (3) of the V2X transmission mode. Figure 4 In the transmission mode of the side link communication shown in FIG. 1 , in step 1, terminal 20A transmits PSCCH and PSSCH to terminal 20B using the resources selected autonomously. Similarly, terminal 20B transmits PSCCH and PSSCH to terminal 20A using the resources selected autonomously (step 1). Figure 4 The transmission mode of the sidelink communication shown is called sidelink transmission mode 2a in NR. In sidelink transmission mode 2 in NR, the terminal 20 performs resource selection itself.

[0053] Figure 5 This is a diagram for explaining example (4) of the V2X transmission mode. Figure 5 In the transmission mode of the sidelink communication shown in FIG. 1 , in step 0, the base station 10 sets a grant for transmitting the sidelink to the terminal 20A via RRC (Radio Resource Control). Then, the terminal 20A transmits the PSSCH to the terminal 20B according to the received resource mode (step 1). Figure 5 The transmission mode of the sidelink communication shown is called sidelink transmission mode 2c in NR.

[0054] Figure 6 This is a diagram for explaining example (5) of the V2X transmission mode. Figure 6 This is a diagram for explaining example (5) of the V2X transmission mode. Figure 6 In the transmission mode of the side link communication shown in FIG. 1 , terminal 20A transmits the scheduling of the side link to terminal 20B via PSCCH in step 1. Then, terminal 20B transmits PSSCH to terminal 20A based on the received scheduling information (step 2). Figure 6 The transmission mode of the sidelink communication shown is called sidelink transmission mode 2d in NR.

[0055] Figure 7 This is a diagram for explaining example (1) of the V2X communication type. Figure 7 The communication type of the side link shown is unicast. Terminal 20A sends PSCCH and PSSCH to terminal 20. Figure 7 In the example shown, the terminal 20A performs unicast to the terminal 20B, and performs unicast to the terminal 20C.

[0056] Figure 8 This is a diagram for explaining example (2) of the V2X communication type. Figure 8 The communication type of the side link shown is multicast. Terminal 20A sends PSCCH and PSSCH to the group to which one or more terminals 20 belong. Figure 8 In the example shown, the group includes the terminal 20B and the terminal 20C, and the terminal 20A performs multicast to the group.

[0057] Fig. 9 This is a diagram for explaining example (3) of the V2X communication type. Fig. 9 The communication type of the side link shown is broadcast. Terminal 20A sends PSCCH and PSSCH to one or more terminals 20. Fig. 9 In the example shown, terminal 20A broadcasts to terminal 20B, terminal 20C, and terminal 20D. Figure 7 to Figure 9 The terminal 20A shown is referred to as a head-UE.

[0058] In addition, in NR-V2X, it is envisioned to support HARQ in unicast and multicast of the side link. In addition, in NR-V2X, SFCI (Sidelink Feedback Control Information) including HARQ response is defined. In addition, research is underway to send SFCI via PSFCH (Physical Sidelink Feedback Channel).

[0059] In addition, in the following description, it is assumed that PSFCH is used in the transmission of HARQ-ACK in the side link, but this is only an example. For example, PSCCH can be used to transmit HARQ-ACK in the side link, PSSCH can be used to transmit HARQ-ACK in the side link, or other channels can be used to transmit HARQ-ACK in the side link.

[0060] As described above, it is envisioned to support HARQ actions in NR-V2X. However, in the structure envisioned in NR-V2X, no specific solution is proposed on how to multiplex and send multiple HARQ-ACKs corresponding to SL data and DL data. No specific solution is proposed on the structure of the HARQ codebook corresponding to SL data and DL data. In addition, no specific solution is proposed on the payload size of the HARQ-ACK corresponding to the SL data and DL data. Therefore, in the prior art, there is a problem that multiple HARQ-ACK reports cannot be properly implemented.

[0061] In the following, for convenience of explanation, all information reported by the terminal 20 in HARQ is referred to as HARQ-ACK. The HARQ-ACK may also be referred to as HARQ-ACK information. In addition, more specifically, the codebook for the HARQ-ACK information reported from the terminal 20 to the base station 10, etc. is referred to as the HARQ-ACK codebook. The HARQ-ACK codebook specifies the bit string of the HARQ-ACK information. In addition, using "HARQ-ACK", NACK is also sent in addition to ACK.

[0062] (Example 1)

[0063] In Example 1, Figure 2 In the side link transmission mode 1 shown, the terminal 20B that has received the SL data using the PSSCH transmits HARQ-ACK to the terminal 20A that has transmitted the data using the PSFCH. In addition, the terminal 20A transmits HARQ-ACK including the HARQ-ACK to the base station 10.

[0064] <Configuration example of embodiment 1>

[0065] Fig.10 1 is a diagram showing the configuration (and operation) of the wireless communication system in Embodiment 1. This configuration may be similarly applied to Embodiment 2.

[0066] like Fig.10 As shown in FIG. 1 , the wireless communication system of the first embodiment includes a base station 10, a terminal 20A, and a terminal 20B. In addition, there are actually a plurality of user devices, but Fig.10The terminal 20A and the terminal 20B are shown as examples.

[0067] Hereinafter, when the terminals 20A, 20B, etc. are not particularly distinguished, they are simply referred to as "terminal 20" or "user device". Fig.10 In the embodiment, as an example, the case where the terminal 20A and the terminal 20B are both within the coverage of the cell is shown, but the operation in the embodiment 1 can also be applied to the case where the terminal 20B is outside the coverage.

[0068] As described above, in this embodiment, the terminal 20 is a device mounted on a vehicle such as a car, and has a cellular communication function and a side link function as a UE in LTE or NR. The terminal 20 may also be a general portable terminal (smartphone, etc.). In addition, the terminal 20 may also be an RSU. The RSU may be a UE-type RSU having the function of a UE, or a gNB-type RSU having the function of a base station device.

[0069] The terminal 20 does not need to be a device having a single housing. For example, even when various sensors are dispersedly arranged in a vehicle, a device including the various sensors is also the terminal 20 .

[0070] In addition, the processing content of the transmission data of the side link of the terminal 20 is basically the same as the processing content of the UL transmission in LTE or NR. For example, the user device 20 scrambles the codeword of the transmission data, modulates it to generate complex-valued symbols, maps the complex-valued symbols (transmission signal) to layer 1 or layer 2, and performs precoding. Then, the precoded complex-valued symbols are mapped to resource elements to generate a transmission signal (for example, complex-valued time-domain SC-FDMA signal: complex-valued time-domain SC-FDMA signal), and sent from each antenna port.

[0071] In addition, the base station 10 has a cellular communication function as a base station in LTE or NR, and a function for enabling the terminal 20 in this embodiment to communicate (for example, resource pool setting, resource allocation, etc.). In addition, the base station 10 can also be an RSU (gNB type RSU).

[0072] Furthermore, in the wireless communication system of the first embodiment, the signal waveform used by the terminal 20 in the SL or UL may be OFDMA, SC-FDMA, or other signal waveforms.

[0073] <Operation Example of Embodiment 1>

[0074] Reference Fig.10 An operation example of the wireless communication system in the first embodiment is described.

[0075] In S101, the base station 10 transmits DCI (Downlink Control Information) to the terminal 20A using the PDCCH, thereby performing SL scheduling. Hereinafter, for convenience of description, DCI for SL scheduling is referred to as SL scheduling DCI (SL scheduling DCI).

[0076] In addition, in the present embodiment 1, the following situation is assumed: in S101, the base station 10 also sends DCI for DL ​​scheduling (also referred to as DL allocation) to the terminal 20A using the PDCCH. Hereinafter, for the convenience of explanation, the DCI for DL ​​scheduling is referred to as DL scheduling DCI (DL scheduling DCI). The terminal 20A that receives the DL scheduling DCI uses the resources specified by the DL scheduling DCI to receive DL data using the PDSCH.

[0077] In S102 and S103, the terminal 20A uses the resources specified by the SL scheduling DCI to send SCI (Sidelink Control Information) using PSCCH, and sends SL data using PSSCH. In addition, in the SL scheduling DCI, only the resources of PSSCH can be specified. In this case, for example, the terminal 20A can send SCI (PSCCH) using the same time resources as the time resources of PSSCH and using frequency resources adjacent to the frequency resources of PSSCH.

[0078] The terminal 20B receives the SCI (PSCCH) and SL data (PSSCH) transmitted from the terminal 20A. The SCI received using the PSCCH includes information on the resources of the PSFCH for the terminal 20B to transmit HARQ-ACK for reception of the data.

[0079] The information of the resource is included in the DL scheduling DCI or SL scheduling DCI sent from the base station 10 in S101, and the terminal 20A may also obtain the information of the resource from the DL scheduling DCI or SL scheduling DCI and include it in the SCI. Alternatively, assuming that the DCI sent from the base station 10 does not include the information of the resource, the terminal 20A autonomously includes the information of the resource in the SCI and sends it.

[0080] In S104 , the terminal 20B transmits HARQ-ACK for the received data to the terminal 20A using the resources of the PSFCH specified by the received SCI.

[0081] In S105, the terminal 20A, for example, sends HARQ-ACK using the PUCCH resource specified by the DL scheduling DCI (or the SL scheduling DCI) at the timing (for example, the timing in time slots) specified by the DL scheduling DCI (or the SL scheduling DCI), and the base station 10 receives the HARQ-ACK. The codebook of the HARQ-ACK may include the HARQ-ACK received from the terminal 20B and the HARQ-ACK for the DL data. However, in the case where there is no allocation of DL data, the HARQ-ACK for the DL data is not included.

[0082] <Example 1: Processing content related to HARQ-ACK codebook>

[0083] An example of a configuration method of the HARQ-ACK codebook transmitted by the terminal 20A to the base station 10 will be described in more detail below.

[0084] <Construction>

[0085] The DL scheduling DCI and SL scheduling DCI received by the terminal 20A include the value of the PDSCH / PDCCH-to-HARQ_feedback timing indicator field respectively. When the value indicates the same time slot in the DL scheduling DCI and the SL scheduling DCI, the terminal 20A uses the same PUCCH resource to send the HARQ-ACK for the DL data and the HARQ-ACK for the SL data (the HARQ-ACK received by the terminal 20A from the terminal 20B in S104). That is, in this case, the terminal 20A includes the HARQ-ACK for the DL data and the HARQ-ACK for the SL data (the HARQ-ACK received by the terminal 20A in S104) in one HARQ-ACK codebook and sends the HARQ-ACK codebook.

[0086] The above-mentioned “PDSCH / PDCCH-to-HARQ_feedback timing indicator field” means “PDSCH-to-HARQ_feedback timing indicator field” or “PDCCH-to-HARQ_feedbacktiming indicator field”.

[0087] "PDSCH-to-HARQ_feedback timing indicator field" is a field included in the DL scheduling DCI, and this value represents the HARQ feedback timing (e.g., number of time slots) starting from the reception of the PDSCH (DL data).

[0088] "PDCCH-to-HARQ_feedback timing indicator field" is a field included in the SL scheduling DCI, and its value represents the HARQ feedback timing (e.g., number of time slots) starting from the reception of the PDCCH (this SL scheduling DCI).

[0089] The above are only examples. The DL scheduling DCI may also include the "PDCCH-to-HARQ_feedback timing indicator field", and the SL scheduling DCI may also include the "PDSCH-to-HARQ_feedback timing indicator field".

[0090] The above processing content can be replaced, for example, with "The value of the PDSCH-to-HARQ_feedback timing indicator field is included in the DL scheduling DCI received by the terminal 20A, and the value of the PDCCH-to-HARQ_feedback timing indicator field is included in the SL scheduling DCI. When these values indicate the same time slot as the HARQ feedback timing, the terminal 20A uses the same PUCCH resource to send the HARQ-ACK for the DL data and the HARQ-ACK for the SL data (the HARQ-ACK received by the terminal 20A in S104)".

[0091] Fig.11 An example of DCI reception and HARQ-ACK transmission in the terminal 20A is shown. In Fig.11 DCI 1 represents the DL scheduling DCI, and DCI 2 represents the SL scheduling DCI. In Fig.11 For example, in time slot 1, the terminal 20A receives DCI 1 and DCI 2. When they both indicate that time slot 5 is the HARQ feedback timing, the terminal 20A uses the PUCCH resource 1 to send a HARQ-ACK codebook including the HARQ-ACK for the DL data and the HARQ-ACK for the SL data to the base station 10.

[0092] <Order of HARQ-ACK>

[0093] Regarding the order of HARQ-ACK when the terminal 20 generates a HARQ-ACK codebook including HARQ-ACK for DL ​​data and HARQ-ACK for SL data, there are the following options A, B, and C.

[0094] Option A) In option A, for example, Fig.12 As shown in (a), the HARQ-ACK for DL ​​data is first stored (in Fig.12 In the example, it is denoted as Uu HARQ-ACK), and then the HARQ-ACK for the SL data is stored (denoted as SL HARQ-ACK).

[0095] Option B) In option B, for example, Fig.12 As shown in (b), the HARQ-ACK for the SL data is stored first, and then the HARQ-ACK for the DL data is stored.

[0096] In addition, Fig.12 In the example of , the case where the HARQ-ACK codebook is composed of 4-bit HARQ-ACK information bits is shown, and as an example, the case where all bits are 1 is shown. In addition, it is assumed that Fig.12 The left end of the HARQ-ACK codebook shown indicates the start of the order in which the bits of the HARQ-ACK codebook are arranged, and the bits are arranged from the left end to the right.

[0097] In addition, Fig.12 In the example, it is assumed that the terminal 20A sends SL data (PSSCH) to multiple user devices and receives HARQ-ACK for the SL data from the multiple user devices.

[0098] When the terminal 20A receives HARQ-ACK for SL data from multiple user devices and stores the HARQ-ACK from each user device in each bit of the HARQ-ACK codebook, the order in which the HARQ-ACK from the multiple user devices are arranged in the HARQ-ACK codebook is determined, for example, based on the UE-IDs of the multiple user devices (for example, in order from large to small IDs or in order from small to large IDs). Alternatively, when the terminal 20A receives SL scheduling DCI for multiple user devices from the base station 10 in order to send SL data to multiple user devices, the order in which the HARQ-ACK from the multiple user devices are arranged in the HARQ-ACK codebook can be determined according to the time order in which the SL scheduling DCI is received, or the order in which the HARQ-ACK from the multiple user devices are arranged in the HARQ-ACK codebook can be determined according to the time order in which each SCI sent to the multiple user devices is sent.

[0099] Option C) In Option C, instead of the determination method in which the order is predetermined as described above, the order is specified in the DL scheduling DCI or SL scheduling DCI received by the terminal 20A, and the order is determined according to the specification.

[0100] <dai>

[0101] The DL scheduling DCI (or the SL scheduling DCI) contains the DAI (Downlink assignment index). Fig.13 This is a diagram for explaining an example of the DAI. In the Fig.13 example, an example of the following situation is shown: A setting for the terminal 20A is made such that HARQ-ACK for the DL data received in time slot 6 (DL) and the DL data received in time slot 7 (DL) is transmitted in time slot 9 (UL). In this case, as an example, the DCI for allocating the DL data received in time slot 6 contains 1 as the DAI, and the DCI for allocating the DL data received in time slot 7 contains 2 as the DAI. Thus, the terminal 20A can determine whether it has received the DL data corresponding to the HARQ-ACK that should be transmitted in time slot 9. Regarding the DAI, there are the following options D and option E.

[0102] Option D) In option D, the SL scheduling DCI sent from the base station 10 to the terminal 20A does not contain the DAI, and the DAI contained in the DL scheduling DCI has no association with the HARQ-ACK for the SL data.

[0103] In this case, regarding the terminal 20B that receives the SL data in the PSSCH, for example, it may be that the terminal 20A includes the DAI for the SL data in the SCI sent through the PSCCH, and the terminal 20B obtains the DAI from the SCI and uses it.

[0104] Option E) In option E, the SL scheduling DCI sent from the base station 10 to the terminal 20A contains the DAI. This DAI is included in the SCI and sent from the terminal 20A to the terminal 20B using the PSCCH, and the terminal 20B uses this DAI to perform the HARQ-ACK transmission for the SL. Regarding the transmission of the HARQ-ACK for the DL data, the terminal 20A uses the DAI contained in the DL scheduling DCI.

[0105] <PUCCH resource>

[0106] Regarding the PUCCH resource, there are the following options F to H.

[0107] Option F) In option F, in terminal 20A, the PUCCH resources for sending the HARQ-ACK codebook including HARQ-ACK for DL ​​data and HARQ-ACK for SL data (or, including HARQ ACK for DL ​​data or HARQ-ACK for SL data) are determined by the last received DCI among multiple DL scheduling DCIs having a PDSCH-to-HARQ_feedbacktiming indicator field specifying the same time slot.

[0108] That is, for example, terminal 20A receives DCI-A, DCI-B, and DCI-C in sequence as DL scheduling DCI. When DCI-A, DCI-B, and DCI-C respectively contain values ​​specifying the same time slot as PDSCH-to-HARQ_feedback timing, terminal 20A uses the PUCCH resources included in DCI-C to send the HARQ-ACK codebook in the time slot.

[0109] Option G) In option G, in terminal 20A, the PUCCH resources for sending the HARQ-ACK codebook including HARQ-ACK for DL ​​data and HARQ-ACK for SL data (or, including HARQ ACK for DL ​​data or HARQ-ACK for SL data) are determined by the last received DCI among multiple SL scheduling DCIs with PDSCH / PDCCH-to-HARQ_feedback timing indicator field specifying the same time slot.

[0110] That is, for example, terminal 20A receives DCI-A, DCI-B, and DCI-C in sequence as SL scheduling DCI. When DCI-A, DCI-B, and DCI-C respectively include values ​​specifying the same time slot as PDSCH / PDCCH-to-HARQ_feedback timingindicator field, terminal 20A uses the PUCCH resources included in DCI-C to send the HARQ-ACK codebook in the time slot.

[0111] Option H) In option H, in terminal 20A, the PUCCH resources for sending the HARQ-ACK codebook including HARQ-ACK for DL ​​data and HARQ-ACK for SL data (or, including HARQ ACK for DL ​​data or HARQ-ACK for SL data) are determined by the last received DCI among one or more SL scheduling DCIs and one or more DL scheduling DCIs having a PDSCH / PDCCH-to-HARQ_feedback timing indicator field specifying the same time slot.

[0112] That is, for example, terminal 20A receives DCI-A and DCI-B in sequence as SL scheduling DCI, and then receives DCI-C as DL scheduling DCI. When DCI-A, DCI-B, and DCI-C respectively include values ​​specifying the same time slot as PDSCH / PDCCH-to-HARQ_feedback timing indicator field, terminal 20A uses the PUCCH resources included in DCI-C to send the HARQ-ACK codebook in the time slot.

[0113] In addition, when a PUCCH resource and a PUSCH resource collide with each other (at least when they are allocated to the same time resource), the terminal 20A may transmit the HARQ-ACK codebook using the PUSCH resource instead of the PUCCH resource.

[0114] <Other Examples>

[0115] In the above example, the DCI transmitted from the base station 10 to the terminal 20A includes information on the resources of the PSFCH used by the terminal 20B to transmit HARQ-ACK, and the SCI transmitted from the terminal 20A includes information on the resources of the PSFCH.

[0116] Instead of this, neither the DL scheduling DCI nor the SL scheduling DCI sent from the base station 10 to the terminal 20A may include the information on the resources of the PSFCH, and the SCI sent from the terminal 20A may also not include the information on the resources of the PSFCH.

[0117] In this case, for example, the terminal 20B that has received the SCI corresponding to the SL data autonomously selects resources of the PSFCH, and uses the selected resources to send a HARQ-ACK for the SL data to the terminal 20A.

[0118] Furthermore, the terminal 20A may include a PSFCH resource indicator (PSFCH resource indicator) (abbreviated as PRI) in the SCI transmitted to the terminal 20B, and the value of the PRI may indicate whether or not a PSFCH resource is designated.

[0119] For example, if PRI=000, the terminal 20B determines that no PSFCH resource is specified and selects a resource autonomously. Also, for example, if PRI is a value greater than 000 (e.g., 010), the terminal 20B selects a PSFCH resource corresponding to the value and uses it to send HARQ-ACK for SL data.

[0120] (Example 2)

[0121] In Example 2, Figure 2 In the sidelink transmission mode 1 shown, the terminal 20B that received the SL data using the PSSCH transmits HARQ-ACK to the terminal 20A that transmitted the data using the PSFCH. Next, the terminal 20A transmits HARQ-ACK including the HARQ-ACK and HARQ-ACK related to PDSCH reception to the base station 10.

[0122] <Configuration example of embodiment 2>

[0123] Fig.14 This is a diagram showing the configuration (and operation) of a wireless communication system in the second embodiment.

[0124] In S201, the base station 10 uses the PDCCH to send DCI to the terminal 20A, thereby performing SL scheduling. In S202, the base station 10 uses the PDCCH to send DCI for DL ​​scheduling to the terminal 20A. The terminal 20A that receives the DL scheduling DCI uses the resources specified by the DL scheduling DCI to receive DL data using the PDSCH. The execution order of S201 and S202 can be reversed, and S202 can also be executed after S203 or S204.

[0125] In S203, the terminal 20A uses the resources specified by the SL scheduling DCI to send SCI using PSCCH and to send SL data using PSSCH. In addition, in the SL scheduling DCI, only the resources of PSSCH may be specified. In this case, for example, the terminal 20A may send SCI (PSCCH) using the same time resources as the time resources of PSSCH and using frequency resources adjacent to the frequency resources of PSSCH.

[0126] The terminal 20B receives the SCI (PSCCH) and the SL data (PSSCH) transmitted from the terminal 20A. The SCI received using the PSCCH may include information on the resources of the PSFCH for the terminal 20B to transmit the HARQ-ACK for the reception of the data.

[0127] The resource information may be included in the DL scheduling DCI or SL scheduling DCI sent from the base station 10 in S201 and S202, and the terminal 20A obtains the resource information from the DL scheduling DCI or SL scheduling DCI and includes it in the SCI. Alternatively, the DCI sent 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 send it.

[0128] In S204 , the terminal 20B transmits HARQ-ACK for the received data to the terminal 20A using the resources of the PSFCH specified by the received SCI.

[0129] In S205, the terminal 20A, for example, sends HARQ-ACK using the PUCCH resources specified by the DL scheduling DCI (or the SL scheduling DCI) at the timing (e.g., timing in time slots) specified by the DL scheduling DCI (or the SL scheduling DCI), and the base station 10 receives the HARQ-ACK. The codebook of the HARQ-ACK may include the HARQ-ACK for SL data and the HARQ-ACK for DL ​​data received from the terminal 20B. However, in the case where there is no allocation of DL data, the HARQ-ACK for DL ​​data may not be included.

[0130] Here, the terminal 20A may use one PUCCH resource to send multiple HARQ-ACK bits including the HARQ-ACK for the SL data. For example, the HARQ-ACK corresponding to the DL data may be multiplexed with the HARQ-ACK corresponding to the SL data on one HARQ-ACK codebook.

[0131] For example, the HARQ-ACK corresponding to the DL data and the HARQ-ACK corresponding to the SL data may be multiplexed using the HARQ-ACK codebook corresponding to the DL data.

[0132] For example, a type 1 HARQ-ACK codebook as a semi-static HARQ-ACK codebook may be applied to the HARQ-ACK corresponding to the DL data and the HARQ-ACK codebook corresponding to the SL data. For example, the HARQ-ACK payload size in the type 1 HARQ-ACK codebook may be a size obtained by adding the "payload size of the HARQ-ACK corresponding to the DL data" to the "number of PSCCH and PSSCH transmission opportunities fed back at the same timing". In addition, when neither PDSCH nor PSSCH is received in the PDSCH transmission opportunity or the PSSCH transmission opportunity, a NACK may be generated and transmitted.

[0133] In addition, for example, a HARQ-ACK codebook of type 2 as a dynamic HARQ-ACK codebook may also be applied to the HARQ-ACK corresponding to the DL data and the HARQ-ACK codebook corresponding to the SL data. For example, the HARQ-ACK payload size in the HARQ-ACK codebook of type 2 may be notified to the terminal 20A by the DAI.

[0134] The information notified by DAI may be a counter including PDSCH, PSCCH and PSSCH sent from the transmitting UE to the receiving UE, or the sum of PDSCH, PSCCH and PSSCH sent from the transmitting UE to the receiving UE.

[0135] NACK may be generated and transmitted if erroneous detection of a PDCCH is detected by the DAI.

[0136] By using the above-mentioned type 1 HARQ-ACK codebook or type 2 HARQ-ACK codebook, the terminal 20A can report HARQ-ACK corresponding to DL data and HARK-ACK corresponding to SL data at arbitrary timing, and can process SL as one CC (Component Carrier) of DL.

[0137] As another example, when the HARQ-ACK corresponding to DL data and the HARQ-ACK corresponding to SL data are multiplexed, the HARQ-ACK codebook related to the DL data and the HARQ-ACK codebook related to the SL data can be used separately.

[0138] For example, the HARQ-ACK codebook associated with DL data and the HARQ-ACK codebook associated with SL data may be set separately through higher layer parameters, or may be defined in advance using specifications.

[0139] For example, regarding the HARQ-ACK codebook related to DL data or the HARQ-ACK codebook related to SL data, the same HARQ-ACK codebook as that of the other party may be applied to one party. That is, the HARQ-ACK codebook related to DL data may be set in the same manner as the HARQ-ACK codebook related to SL data, and the HARQ-ACK codebook related to SL data may also be set in the same manner as the HARQ-ACK codebook related to DL data.

[0140] When the HARQ-ACK codebook related to DL data and the HARQ-ACK codebook related to SL data are used separately, and the HARQ-ACK codebook of type 1 as a semi-static HARQ-ACK codebook is applied to the HARQ-ACK codebook related to SL data, the HARQ-ACK payload size of the HARQ-ACK codebook of type 1 may correspond to the number of PSCCH and PSSCH transmission opportunities fed back at the same timing. In addition, NACK may also be generated and transmitted when PSCCH and PSSCH are not received through any of the PSCCH and PSSCH transmission opportunities.

[0141] For example, the order of HARQ-ACK bits in the type 1 HARQ-ACK codebook may be the order of HARK-ACK corresponding to DL data and HARQ-ACK corresponding to SL data, or the order of HARK-ACK corresponding to SL data and HARQ-ACK corresponding to DL data.

[0142] In the case where the type 1 HARQ-ACK codebook is applied to the HARQ-ACK codebook related to the SL data, and the PUCCH overlaps with the PUSCH, and the HARQ-ACK bits are multiplexed on the PUSCH, the DAI contained in the UL grant can use a 2-bit field to indicate the presence of HARK-ACK corresponding to the DL data and HARQ-ACK corresponding to the SL data. Alternatively, in the case where the PUCCH overlaps with the PUSCH and the HARQ-ACK bits are multiplexed on the PUSCH, the DAI contained in the UL grant can indicate the presence of any one of the HARK-ACK corresponding to the DL data and the HARQ-ACK corresponding to the SL data. Alternatively, in the case where the PUCCH overlaps with the PUSCH and the HARQ-ACK bits are multiplexed on the PUSCH, the DAI contained in the UL grant can indicate the presence of at least any one of the HARK-ACK corresponding to the DL data and the HARQ-ACK corresponding to the SL data.

[0143] When the HARQ-ACK codebook related to DL data and the HARQ-ACK codebook related to SL data are used separately, and the HARQ-ACK codebook of type 2 as a dynamic HARQ-ACK codebook is applied to the HARQ-ACK codebook related to SL data, the HARQ-ACK payload size of the HARQ-ACK codebook of type 2 can be notified by DAI. DAI can also be counted or managed separately in the HARQ-ACK codebook related to DL data and the HARQ-ACK codebook related to SL data.

[0144] The information notified by DAI may be a counter obtained by adding PDSCH, and PSCCH and PSSCH sent from the transmitting UE to the receiving UE, or may be the sum of PDSCH, PSCCH and PSSCH sent from the transmitting UE to the receiving UE.

[0145] NACK may be generated and transmitted if erroneous detection of a PDCCH is detected by the DAI.

[0146] In the case where a type 2 HARQ-ACK codebook is applied to a HARQ-ACK codebook related to SL data, and the PUCCH overlaps with the PUSCH, and the HARQ-ACK bits are multiplexed on the PUSCH, the DAI included in the UL grant may use a 2-bit field to indicate the presence of a HARK-ACK corresponding to the DL data and a HARQ-ACK corresponding to the SL data, respectively. Alternatively, in the case where the PUCCH overlaps with the PUSCH, and the HARQ-ACK bits are multiplexed on the PUSCH, the DAI included in the UL grant may indicate the presence of any one of the HARK-ACK corresponding to the DL data and the HARQ-ACK corresponding to the SL data. Alternatively, in the case where the PUCCH overlaps with the PUSCH, and the HARQ-ACK bits are multiplexed on the PUSCH, the DAI included in the UL grant may indicate the presence of at least any one of the HARK-ACK corresponding to the DL data and the HARQ-ACK corresponding to the SL data.

[0147] As another example, terminal 20B may use one PSFCH resource to send a plurality of HARQ-ACK bits including HARQ-ACK for SL data to terminal 20A.

[0148] In the case where a HARQ-ACK codebook of type 1, which is a semi-static HARQ-ACK codebook, is applied to a HARQ-ACK codebook related to SL data, the HARQ-ACK payload size of the HARQ-ACK codebook of type 1 may correspond to the number of PSCCH and PSSCH transmission opportunities in a PSFCH cycle. And, in the case of applying CA, the HARQ-ACK payload size of the HARQ-ACK codebook of type 1 may correspond to the value obtained by multiplying the number of PSCCH and PSSCH transmission opportunities in a PSFCH cycle by the number of CCs. In addition, NACK may also be generated and sent when PSCCH and PSSCH are not received in any of the PSCCH and PSSCH transmission opportunities. In the case where the above-mentioned HARQ-ACK codebook of type 1, which is a semi-static HARQ-ACK codebook, is applied to a HARQ-ACK codebook related to SL data, it is possible to prevent the payload size from being erroneously identified.

[0149] In addition, when a type 2 HARQ-ACK codebook as a dynamic HARQ-ACK codebook is applied to a HARQ-ACK codebook related to SL data, the HARQ-ACK payload size of the type 2 HARQ-ACK codebook may be notified by a sidelink assignment indicator (Sidelink Assignment Indicator) (hereinafter referred to as "SAI") included in the SCI. SAI may have the same function as DAI.

[0150] The information notified by the SAI may be a counter obtained by adding the PSCCH and PSSCH sent from the transmitting UE to the receiving UE, or may be the sum of the PSCCH and PSSCH sent from the transmitting UE to the receiving UE.

[0151] NACK may be generated and transmitted if erroneous detection of the PSCCH is detected by the SAI.

[0152] When the above-mentioned type 2 HARQ-ACK codebook, which is a semi-static HARQ-ACK codebook, is applied to the HARQ-ACK codebook related to SL data, it is possible to prevent redundant bits from being generated.

[0153] The type of the HARQ-ACK codebook applied to the HARQ-ACK codebook related to the SL data can be pre-defined by the specification, can be pre-set, can be set through RRC signaling, and can be notified through MAC-CE (Medium Access Control-Control Element), DCI or SCI.

[0154] In the PSFCH resource, when the HARQ-ACK corresponding to multiple SL data is multiplexed, the PSFCH resource can be associated with the last received SCI, or it can be notified by the last received SCI. In addition, in the PSFCH resource, when the HARQ-ACK corresponding to multiple SL data is multiplexed, the PSFCH resource can be associated with the initially received SCI, or it can be notified by the initially received SCI. In addition, when the HARQ-ACK corresponding to multiple SL data is multiplexed in the PSFCH resource, the PSFCH resource can be associated with the SCI corresponding to the largest subchannel index in the received SCI, or it can be notified by the SCI corresponding to the largest subchannel index in the received SCI. In addition, when the HARQ-ACK corresponding to multiple SL data is multiplexed in the PSFCH resource, the PSFCH resource can be associated with the SCI corresponding to the smallest subchannel index in the received SCI, or it can be notified by the SCI corresponding to the smallest subchannel index in the received SCI. In addition, when HARQ-ACK corresponding to multiple SL data is multiplexed in the PSFCH resource, the PSFCH resource can be associated with the SCI corresponding to the largest CC index in the received SCI, or can be notified by the SCI corresponding to the largest CC index in the received SCI. In addition, when HARQ-ACK corresponding to multiple SL data is multiplexed in the PSFCH resource, the PSFCH resource can be associated with the SCI corresponding to the smallest CC index in the received SCI, or can be notified by the SCI corresponding to the smallest CC index in the received SCI. By establishing an association as described above, the PSFCH for HARQ-ACK multiplexing can be shared between the sending side and the receiving side.

[0155] In addition, the method of reporting HARQ-ACK from the terminal 20A to the base station 10 and the method of reporting HARQ-ACK from the terminal 20B to the terminal 20A can be used in combination. That is, the method of reporting HARQ-ACK from the terminal 20A to the base station 10 can be further applied to the method of reporting HARQ-ACK from the terminal 20B to the terminal 20A, and the method of reporting HARQ-ACK from the terminal 20A to the base station 10 can be further applied to the method of reporting HARQ-ACK from the terminal 20B to the terminal 20A.

[0156] According to the above-mentioned embodiment, the terminal 20 can apply the HARQ-ACK codebook to multiplex the HARQ-ACK corresponding to the SL data and the HARQ-ACK corresponding to the DL data to report to the base station 10. In addition, the terminal 20 can apply the HARQ-ACK codebook to multiplex the HARQ-ACK corresponding to multiple SL data to report to the transmitting side terminal 20.

[0157] That is, in inter-terminal direct communication, retransmission control can be appropriately performed.

[0158] (Device Structure)

[0159] Next, the functional configuration examples of the base station 10 and the terminal 20 that perform the above-described processing and operation are described. The base station 10 and the terminal 20 include functions for implementing the above-described embodiments. However, the base station 10 and the terminal 20 may each include only a part of the functions in the embodiments.

[0160] <Base station 10>

[0161] Fig.15 1 is a diagram showing an example of the functional configuration of the base station 10. Fig.15 As shown, the base station 10 includes a transmission unit 110 , a reception unit 120 , a setting unit 130 , and a control unit 140 . Fig.15 The functional configuration shown is only an example, and any functional division and name of the functional unit may be used as long as the operation involved in the embodiment of the present invention can be performed.

[0162] The transmitting unit 110 includes a function of generating a signal to be transmitted to the terminal 20 side and transmitting the signal wirelessly. The receiving unit 120 includes a function of receiving various signals transmitted from the terminal 20 and obtaining, for example, higher layer information from the received signals. In addition, the transmitting unit 110 has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, DL reference signals, etc. to the terminal 20.

[0163] The setting unit 130 stores the preset setting information and various setting information to be transmitted to the terminal 20 in a storage device, and reads the setting information from the storage device as needed. The content of the setting information is, for example, information related to the setting of the D2D communication.

[0164] As described in the embodiment, the control unit 140 performs processing related to the setting for the terminal 20 to perform D2D communication. In addition, the control unit 140 sends the scheduling of D2D communication and DL communication to the terminal 20 via the transmission unit 110. In addition, the control unit 140 receives information related to the HARQ response of the D2D communication and DL communication from the terminal 20 via the reception unit 120. The functional unit related to signal transmission in the control unit 140 may be included in the transmission unit 110, and the functional unit related to signal reception in the control unit 140 may be included in the reception unit 120.

[0165] <Terminal 20>

[0166] Fig.16 2 is a diagram showing an example of the functional structure of the terminal 20. Fig.16 As shown, the terminal 20 includes a transmitting unit 210 , a receiving unit 220 , a setting unit 230 , and a control unit 240 . Fig.16 The functional configuration shown is only an example, and any functional division and name of the functional unit may be used as long as the operation involved in the embodiment of the present invention can be performed.

[0167] The transmitting unit 210 generates a transmission signal according to the transmission data, and transmits the transmission signal wirelessly. The receiving unit 220 receives various signals wirelessly, and obtains a higher layer signal from the received physical layer signal. In addition, the receiving unit 220 has a function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signals or reference signals, etc. transmitted from the base station 10. In addition, for example, as D2D communication, 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, and the receiving unit 220 receives PSCCH, PSSCH, PSDCH or PSBCH, etc. from other terminals 20.

[0168] The setting unit 230 stores various setting information received by the receiving unit 220 from the base station 10 or the terminal 20 in the storage device, and reads it from the storage device as needed. In addition, the setting unit 230 also stores pre-set setting information. The content of the setting information is, for example, information related to the setting of D2D communication.

[0169] As described in the embodiment, the control unit 240 controls the D2D communication with other terminals 20. In addition, the control unit 240 performs processing related to HARQ of D2D communication and DL communication. In addition, the control unit 240 sends information related to HARQ responses of D2D communication and DL communication to other terminals 20 scheduled from the base station 10 to the base station 10. In addition, the control unit 240 may also schedule D2D communication for other terminals 20. The functional unit related to signal transmission in the control unit 240 may also be included in the transmission unit 210, and the functional unit related to signal reception in the control unit 240 may also be included in the reception unit 220.

[0170] (Hardware Structure)

[0171] The block diagram used in the description of the above embodiment ( Fig.15 and Fig.16 ) shows blocks in units of functions. These functional blocks (structural parts) are implemented by any combination of at least one of hardware and software. In addition, there is no particular limitation on the implementation method of each functional block. That is, each functional block can be implemented using a device that is physically or logically combined, or two or more physically or logically separated devices can be directly or indirectly connected (for example, using wires, wirelessly, etc.) and implemented using these multiple devices. The functional block can also be implemented by combining software with the above-mentioned one device or the above-mentioned multiple devices.

[0172] Functionally, it includes judging, deciding, determining, calculating, calculating, processing, deriving, investigating, searching, confirming, receiving, sending, outputting, accessing, solving, selecting, selecting, establishing, comparing, assuming, expecting, regarding, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc., but is not limited to these. For example, the functional block (structural part) that enables the sending function is called a transmitting unit or a transmitter. In short, as mentioned above, there is no particular limitation on the implementation method.

[0173] For example, the base station 10 , the terminal 20 , and the like in one embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig.17 1 is a diagram showing an example of the hardware structure of a base station 10 and a terminal 20 according to an embodiment of the present disclosure. The base station 10 and the terminal 20 described above may also 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, and the like.

[0174] In the following description, the word "device" may be replaced by "circuit", "device", "unit", etc. The hardware structure of the base station 10 and the terminal 20 may be configured to include one or more of the devices shown in the figure, or may be configured to exclude some of the devices.

[0175] Each function in the base station 10 and the terminal 20 is implemented by the following method: predetermined software (program) is read into hardware such as the processor 1001 and the storage device 1002, so that the processor 1001 performs calculations and controls the communication of the communication device 1004 or controls at least one of the reading and writing of data in the storage device 1002 and the auxiliary storage device 1003.

[0176] The processor 1001 controls the entire computer by, for example, running an operating system. The processor 1001 may also be composed of a central processing unit (CPU) including an interface with peripheral devices, a control device, a computing device, registers, etc. For example, the control unit 140, the control unit 240, etc., may also be implemented by the processor 1001.

[0177] In addition, the processor 1001 reads a program (program code), a software module, or data from at least one of the auxiliary storage device 1003 and the communication device 1004 to the storage device 1002, and performs various processes accordingly. As a program, a program that causes the computer to execute at least a part of the actions described in the above embodiments is used. For example, Fig.15 The control unit 140 of the base station 10 shown may also be implemented by a control program stored in the storage device 1002 and executed in the processor 1001. In addition, for example, Fig.16 The control unit 240 of the terminal 20 shown can also be implemented by a control program stored in the storage device 1002 and running in the processor 1001. Regarding the above-mentioned various processes, although it is described that the above-mentioned various processes are performed by one processor 1001, the above-mentioned various processes can also be performed simultaneously or sequentially by more than two processors 1001. The processor 1001 can also be installed by more than one chip. In addition, the program can also be sent from the network via a telecommunication line.

[0178] The storage device 1002 is a computer-readable recording medium, and may be composed of at least one of 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 referred to as a register, a cache, a main memory (main storage device), etc. The storage device 1002 can store executable programs (program codes), software modules, etc. for implementing the communication method involved in one embodiment of the present disclosure.

[0179] The auxiliary storage device 1003 is a computer-readable recording medium, and may be composed of at least one of an optical disk such as a CD-ROM (CompactDisc ROM), a hard disk drive, a floppy disk, a magneto-optical disk (e.g., a compressed disk, a digital versatile disk, a Blu-ray (registered trademark) disk, a smart card, a flash memory (e.g., a card, a stick, a key drive), a Floppy (registered trademark) disk, a magnetic strip, etc. The above-mentioned storage medium may be, for example, a database, a server, and other appropriate media including at least one of the storage device 1002 and the auxiliary storage device 1003.

[0180] The communication device 1004 is hardware (transceiver device) for communicating between computers via at least one of a wired network and a wireless network, and may also be referred to as a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may also be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc., for example, in order to implement at least one of frequency division duplex (FDD: Frequency Division Duplex) and time division duplex (TDD: Time Division Duplex). For example, a transceiver antenna, an amplifier, a transceiver, a transmission path interface, etc. may also be implemented by the communication device 1004. The transceiver may also be installed by physically or logically separating the transmitter and the receiver.

[0181] The input device 1005 is an input device that receives input from the outside (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.). The output device 1006 is an output device that implements output to the outside (e.g., a display, a speaker, an LED light, etc.). In addition, the input device 1005 and the output device 1006 may also be integrally formed (e.g., a touch panel).

[0182] In addition, the processor 1001 and the storage device 1002 and other devices are connected via a bus 1007 for communicating information. The bus 1007 may be configured using a single bus or may be configured using different buses for each device.

[0183] In addition, the base station 10 and the 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 may also implement a part or all of each functional block through the hardware. For example, the processor 1001 may also be installed using at least one of these hardware.

[0184] (Summary of Implementation Methods)

[0185] As described above, according to an embodiment of the present invention, there is provided a terminal comprising: a receiving unit, which receives from a base station information on a first resource scheduled for direct communication between terminals, information on a second resource scheduled for communication with the base station, and data via the second resource; and a sending unit, which uses the first resource to send data to other terminals, the receiving unit receiving from the other terminals a first response related to retransmission control corresponding to the sent data, the terminal further comprising a control unit, which determines a third response related to retransmission control based on the first response and a second response related to retransmission control corresponding to the data via the second resource, and the sending unit sends the third response to the base station.

[0186] According to the above configuration, the terminal 20 can apply the HARQ-ACK codebook to multiplex the HARQ-ACK corresponding to the SL data and the HARQ-ACK corresponding to the DL data and report them to the base station 10. That is, in the inter-terminal direct communication, retransmission control can be appropriately performed.

[0187] The codebook that specifies "the retransmission response applied to the third response" may be the same as the codebook that specifies "the retransmission response applied to the second response". According to this structure, the terminal 20 can apply the HARQ-ACK codebook to multiplex the HARQ-ACK corresponding to the SL data and the HARQ-ACK corresponding to the DL data and report them to the base station 10.

[0188] When the codebook that specifies "the retransmission response applied to the third response" is semi-static, the payload size of the codebook that specifies "the retransmission response applied to the third response" can be determined based on the first resource and the second resource. According to this structure, the terminal 20 can apply the HARQ-ACK codebook to multiplex the HARQ-ACK corresponding to the SL data and the HARQ-ACK corresponding to the DL data and report them to the base station 10.

[0189] When the codebook that specifies "the retransmission response applied to the third response" is dynamic, the payload size of the codebook that specifies "the retransmission response applied to the third response" can be determined based on the field included in the information for scheduling the first resource or the information for scheduling the second resource. According to this structure, the terminal 20 can apply the HARQ-ACK codebook to multiplex the HARQ-ACK corresponding to the SL data and the HARQ-ACK corresponding to the DL data and report them to the base station 10.

[0190] The codebook that specifies "the retransmission response applied to the first response" and the codebook that specifies "the retransmission response applied to the second response" may be different. According to this structure, the terminal 20 can apply the HARQ-ACK codebook to multiplex the HARQ-ACK corresponding to the SL data and the HARQ-ACK corresponding to the DL data and report them to the base station 10.

[0191] In addition, according to an embodiment of the present invention, a communication method performed by a terminal is provided, which comprises the following steps:

[0192] A receiving step of receiving, from a base station, information on scheduling a first resource for inter-UE direct communication, information on scheduling a second resource for communication with the base station, and data via the second resource; and

[0193] a sending step, using the first resource to send data to other terminals,

[0194] The receiving step includes the step of receiving a first response related to retransmission control corresponding to the transmitted data from the other terminal,

[0195] The terminal further includes a control step of determining a third response related to retransmission control based on the first response and a second response related to retransmission control corresponding to data passing through the second resource,

[0196] The sending step includes a step of sending the third response to a base station.

[0197] According to the above configuration, the terminal 20 can apply the HARQ-ACK codebook to multiplex the HARQ-ACK corresponding to the SL data and the HARQ-ACK corresponding to the DL data and report them to the base station 10. That is, in the inter-terminal direct communication, retransmission control can be appropriately performed.

[0198] (Supplementary Implementation Methods)

[0199] The above describes the embodiments of the present invention, but the disclosed invention is not limited to such embodiments, and those skilled in the art should understand various variations, modifications, substitutions, replacements, etc. In order to promote the understanding of the invention, specific numerical examples are used for description, but unless otherwise specified, these numerical values ​​are only examples, and any appropriate value may also be used. The distinction between the items in the above description is not essential to the present invention. The items recorded in two or more items can be combined and used as needed, and the items recorded in a certain item can be applied to the items recorded in another item (as long as there is no contradiction). The boundaries of the functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of the physical components. The actions of multiple functional units can be performed by one physical component, or the actions of one functional unit can be performed by multiple physical components. Regarding the processing process described in the embodiment, the order of processing can be swapped if there is no contradiction. In order to facilitate the description of the processing, the base station 10 and the terminal 20 are described using functional block diagrams, but such devices can also be implemented in hardware, software, or a combination thereof. The software that operates through the processor of the base station 10 according to the embodiment of the present invention and the software that operates through the processor of the terminal 20 according to the embodiment of the present invention may also 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 and any other appropriate storage medium.

[0200] In addition, the notification of information is not limited to the form / implementation method described in the present disclosure, and other methods may also be used. For example, the notification of information may be implemented through physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), high-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 a combination thereof. In addition, RRC signaling may be referred to as an RRC message, for example, it may also be an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc.

[0201] Each form / implementation described in the present disclosure may also be applied to at least one of LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), NR (New Radio), W-CDMA (registered trademark), GSM (registered trademark), CDMA 2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), systems using other appropriate systems, and next-generation systems extended therefrom. In addition, a combination of a plurality of systems (for example, a combination of at least one of LTE and LTE-A with 5G, etc.) may be applied.

[0202] The processing procedures, timings, processes, etc. of each form / implementation described in this specification may be changed in order without contradiction. For example, for the method described in this disclosure, the elements of various steps are presented in an illustrative order, but are not limited to the specific order presented.

[0203] In this specification, the specific actions performed by the base station 10 are sometimes also performed by its upper node according to the situation. In a network composed of one or more network nodes having the base station 10, various actions performed to communicate with the terminal 20 can be performed by at least one of the base station 10 and other network nodes other than the base station 10 (for example, MME or S-GW, etc., but not limited to these). In the above, the case where there is one other network node other than the base station 10 is illustrated, but the other network node may also be a combination of multiple other network nodes (for example, MME and S-GW).

[0204] The information or signals described in the present disclosure can be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), and can also be input or output via a plurality of network nodes.

[0205] The input or output information can be stored in a specific location (e.g., memory) or managed using a management table. The input or output information can be rewritten, updated, or appended. The output information can also be deleted. The input information can also be sent to other devices.

[0206] The determination in the present disclosure may be performed by a value represented by 1 bit (0 or 1), by a Boolean value (Boolean: true or false), or by comparison of numerical values ​​(for example, comparison with a predetermined value).

[0207] Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or by other names, shall be interpreted broadly to refer to commands, sets of commands, codes, code segments, program codes, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, etc.

[0208] In addition, software, commands, information, etc. may be sent and received via a transmission medium. For example, when software is sent from a web page, server, or other remote source using at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), etc.) and wireless technology (infrared, microwave, etc.), at least one of these wired technology and wireless technology is included in the definition of transmission medium.

[0209] The information, signals, etc. described in the present disclosure may also be represented by any of a variety of different technologies. For example, the data, commands, instructions, information, signals, bits, symbols, chips, etc. that may be involved in the above description as a whole may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any combination of these.

[0210] In addition, the terms described in the present disclosure and the terms required for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may also be a signal (signaling). In addition, a signal may also be a message. In addition, a component carrier (CC) may also be referred to as a carrier frequency, a cell, a frequency carrier, etc.

[0211] As used in this disclosure, the terms "system" and "network" may be used interchangeably.

[0212] In addition, the information, parameters, etc. described in the present disclosure may be represented by absolute values, relative values ​​to predetermined values, or other corresponding information. For example, wireless resources may also be indicated by indexes.

[0213] The names used for the above parameters are not limiting in any way. Furthermore, the formulas etc. using these parameters may sometimes differ from those explicitly disclosed in this disclosure. Various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by all appropriate names, and therefore the various names assigned to these various channels and information elements are not limiting in any way.

[0214] In the present 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 are sometimes referred to as macro cells, small cells, micro cells, and pico cells.

[0215] A base station can accommodate one or more (for example, 3) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can also provide communication services through a base station subsystem (for example, a small base station for indoor use (RRH: Remote Radio Head)). Terms such as "cell" or "sector" refer to a part or the entire coverage area of ​​at least one of the base station and the base station subsystem that provide communication services within the coverage area.

[0216] In the present disclosure, terms such as “mobile station (MS)”, “user terminal (user terminal)”, “user equipment (UE)”, and “terminal” may be used interchangeably.

[0217] For mobile stations, those skilled in the art sometimes also use the following terms: subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other appropriate terms.

[0218] At least one of the base station and the mobile station may also be referred to as a transmitting device, a receiving device, a communication device, etc. In addition, 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 means of transportation (e.g., a car, an airplane, etc.), a mobile body that moves in an unmanned manner (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). In addition, at least one of the base station and the mobile station also includes a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0219] In addition, the base station in the present disclosure may also be replaced by a user terminal. For example, various forms / implementations of the present disclosure may also be applied to a structure in which the communication between a base station and a user terminal is replaced by the communication between multiple terminals 20 (for example, it may also be referred to as D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). In this case, a structure in which the terminal 20 has the functions possessed by the above-mentioned base station 10 may also be formed. In addition, terms such as "uplink" and "downlink" may also be replaced by terms corresponding to communication between terminals (for example, "side"). For example, an uplink channel, a downlink channel, etc. may also be replaced by a side channel.

[0220] Likewise, the user terminal in the present disclosure may be replaced by a base station. In this case, the base station may have the functions of the user terminal described above.

[0221] The terms "determining" and "determining" used in the present disclosure sometimes include a variety of actions. "Judgment" and "determination" may, for example, include treating matters that have been judged, calculated, calculated, processed, derived, investigated, searched (for example, searched in a table, database or other data structure), confirmed (for example, ascertained) as matters that have been "judged" or "determined", etc. In addition, "judgment" and "determination" may include treating matters that have been received (for example, received information), transmitted (for example, sent information), input, output, accessed (for example, accessed data in memory) as matters that have been "judged" or "determined", etc. In addition, "judgment" and "decision" may include treating matters that have been resolved (resolving), selected (selecting), chosen (choosing), established (establishing), compared (comparing), etc. as matters that have been "judged" or "determined". In other words, "judgment" and "decision" may include matters that have been "judged" or "determined" for any action. In addition, "judgment (decision)" may also be replaced by "assuming (assuming)", "expecting (expecting)", "considering (considering)", etc.

[0222] The terms "connected", "coupled" and all variations of these terms are intended to indicate any direct or indirect connection or combination between two or more elements, and may include situations where there is one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The combination or connection between elements may be a physical combination or connection, a logical combination or connection, or a combination of these. For example, "access" may be used to replace "connection". In the context of the present disclosure, two elements may be considered to be "connected" or "coupled" to each other by using at least one of one or more wires, cables and printed electrical connections, and as some non-limiting and non-inclusive examples, by using electromagnetic energy with wavelengths in the wireless frequency domain, microwave region and light (including both visible and invisible) region.

[0223] The reference signal may be referred to as RS (Reference Signal) for short, or may be referred to as a pilot signal according to the applied standard.

[0224] The phrase "according to" used in this disclosure does not mean "only according to" unless otherwise expressly stated. In other words, the phrase "according to" means both "only according to" and "at least according to".

[0225] Any reference to an element using the terms "first", "second", etc. used in this disclosure does not necessarily limit the number or order of these elements. These terms can be used as a simple method to distinguish between two or more elements in this disclosure. Therefore, a reference to a first element and a second element does not mean that only two elements can be used or that the first element must precede the second element in any form.

[0226] The “unit” in the structure of each of the above-mentioned devices may be replaced with a “section”, a “circuit”, a “device”, or the like.

[0227] When the terms "include", "including" and their variations are used in the present disclosure, these terms mean inclusiveness like the term "comprising". Furthermore, the term "or" used in the present disclosure means not an exclusive or.

[0228] A radio frame may be composed of one or more frames in the time domain. In the time domain, one or more frames may be referred to as subframes. A subframe may be composed of one or more time slots in the time domain. A subframe may also be a fixed time length (e.g., 1 ms) that is not dependent on a numerology.

[0229] A parameter set may also be a communication parameter applied to at least one of the transmission and reception of a certain signal or channel. For example, a parameter set may represent at least one of a subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, wireless frame structure, specific filtering processing performed by a transceiver in the frequency domain, specific windowing processing performed by a transceiver in the time domain, and the like.

[0230] A slot may be composed of one or more symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, etc.) in the time domain. A slot may be a time unit based on a parameter set.

[0231] A time slot may contain multiple mini-slots. Each mini-slot may be composed of one or more symbols in the time domain. In addition, a mini-slot may also be referred to as a sub-slot. A mini-slot may be composed of fewer symbols than a time slot. A PDSCH (or PUSCH) transmitted in units of time greater than a mini-slot may be referred to as a PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a mini-slot may be referred to as a PDSCH (or PUSCH) mapping type B.

[0232] A radio frame, a subframe, a time slot, a mini-time slot, and a symbol all represent time units for transmitting signals. A radio frame, a subframe, a time slot, a mini-time slot, and a symbol may be referred to by other corresponding names.

[0233] For example, 1 subframe can be called a transmission time interval (TTI), multiple consecutive subframes can be called a TTI, and 1 time slot or 1 mini time slot can be called a TTI. That is, at least one of the subframe and the TTI can be a subframe (1ms) in the existing LTE, a period shorter than 1ms (for example, 1-13 code elements), or a period longer than 1ms. In addition, the unit representing TTI can be called a time slot, a mini time slot, etc. instead of a subframe.

[0234] Here, TTI refers to, for example, the minimum time unit for scheduling in wireless communication. For example, in the LTE system, the base station schedules each terminal 20 to allocate wireless resources (frequency bandwidth, transmission power, etc. that can be used in each terminal 20) in units of TTI. In addition, the definition of TTI is not limited to this.

[0235] TTI can be a transmission time unit of data packets (transport blocks), code blocks, code words, etc. after channel coding, or a processing unit of scheduling, link adaptation, etc. In addition, when TTI is assigned, the time interval (for example, the number of symbols) to which the transport block, code block, code word, etc. is actually mapped can be shorter than the TTI.

[0236] In addition, when 1 time slot or 1 mini time slot is called TTI, more than one TTI (ie, more than one time slot or more than one mini time slot) can constitute the minimum time unit of scheduling. In addition, the number of time slots (mini time slots) constituting the minimum time unit of scheduling can be controlled.

[0237] A TTI having a time length of 1 ms is also called a normal TTI (TTI in LTE Rel.8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a time slot, etc. A TTI shorter than a normal TTI may be called a shortened TTI, a short TTI, a partial or fractional TTI, a shortened subframe, a short subframe, a mini-time slot, a sub-time slot, a time slot, etc.

[0238] In addition, for a long TTI (longTTI) (for example, a normal TTI, a subframe, etc.), it can be replaced with a TTI having a time length exceeding 1ms, and for a short TTI (short TTI) (for example, a shortened TTI, etc.), it can be replaced with a TTI length that is smaller than the long TTI (longTTI) and has a TTI length of more than 1ms.

[0239] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain. In the frequency domain, it may contain one or more consecutive subcarriers. The number of subcarriers contained in an RB is independent of the parameter set and may be the same, for example, 12. The number of subcarriers contained in an RB may also be determined according to the parameter set.

[0240] In addition, the time domain of an RB may include one or more symbols, and may be the length of 1 slot, 1 mini slot, 1 subframe, or 1 TTI. 1 TTI, 1 subframe, etc. may be composed of one or more resource blocks, respectively.

[0241] In addition, one or more RBs may be referred to as a physical resource block (PRB: Physical RB), a sub-carrier group (SCG: Sub-Carrier Group), a resource element group (REG: Resource Element Group), a PRB pair, an RB pair, and the like.

[0242] In addition, a resource block may be composed of one or more resource elements (REs). For example, 1 RE may be a radio resource region of 1 subcarrier and 1 symbol.

[0243] A bandwidth part (BWP) (also called partial bandwidth, etc.) may also represent a subset of contiguous common resource blocks (RBs) for a parameter set in a carrier. Here, the common RBs may be identified by the index of the RBs based on the common reference point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0244] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be set for the terminal 20 within one carrier.

[0245] At least one of the set BWPs may be active, and it is not conceivable that the terminal 20 transmits and receives a predetermined signal / channel outside the activated BWP. In addition, "cell", "carrier", etc. in the present disclosure may be replaced with "BWP".

[0246] The above structures of radio frames, subframes, time slots, mini-time slots, and symbols are only examples. For example, the number of subframes included in a radio frame, the number of time slots per subframe or radio frame, the number of mini-time slots included in a time slot, the number of symbols and RBs included in a time slot or mini-time slot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP: Cyclic Prefix) length, and the like can be changed in various ways.

[0247] In the present disclosure, when an article is added by translation, such as a, an, and the in English, the present disclosure also includes a case where the noun following the article is in a plural form.

[0248] In the present disclosure, the term "A and B are different" may also mean "A and B are different from each other". In addition, the term may also mean "A and B are different from C, respectively". The terms "separate" and "combined" may also be interpreted in the same way as "different".

[0249] Each form / implementation described in this disclosure may be used alone or in combination, and may be switched according to execution. In addition, notification of scheduled information is not limited to being performed explicitly (e.g., notification of "yes X"), but may also be performed implicitly (e.g., notification of the scheduled information is not performed).

[0250] In the present disclosure, HARQ response is an example of a response related to retransmission control. ACK is an example of a positive response. NACK is an example of a negative response. The HARQ-ACK codebook is an example of a codebook that defines a retransmission response.

[0251] The present disclosure is described in detail above, but it should be 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 a modification and variation without departing from the subject matter and scope of the present disclosure as determined by the claims. Therefore, the purpose of the description of the present disclosure is to illustrate and not to have any limiting meaning on the present disclosure.

[0252] Description of symbols

[0253] This international patent application claims priority based on Japanese Patent Application No. 2019-155835 filed on August 28, 2019, and all contents of Japanese Patent Application No. 2019-155835 are incorporated herein by reference.

[0254] 10: Base station;

[0255] 110: Sending department;

[0256] 120: receiving unit;

[0257] 130: Setting department;

[0258] 140: Control Department;

[0259] 20: Terminal;

[0260] 210: Sending department;

[0261] 220: receiving unit;

[0262] 230: Setting department;

[0263] 240: Control Department;

[0264] 1001: processor;

[0265] 1002: storage device;

[0266] 1003: auxiliary storage device;

[0267] 1004: Communication device;

[0268] 1005: input device;

[0269] 1006: Output device.< / dai>

Claims

1. A terminal comprising: a receiving unit configured to receive, from a base station, information on scheduling a first resource for inter-UE direct communication, information on scheduling a second resource for communication with the base station, and data via the second resource; and a sending unit, which uses the first resource to send data to other terminals, the receiving unit receives, from the other terminal, a first response related to retransmission control corresponding to the transmitted data, The terminal further includes a control unit that determines a third response related to retransmission control based on the first response and a second response related to retransmission control corresponding to data passing through the second resource. the transmitting unit transmits the third response to the base station, The codebook that specifies "the retransmission response to be applied to the third response" is the same as the codebook that specifies "the retransmission response to be applied to the second response", In the case where the codebook defining "a retransmission response applied to the third response" is dynamic, the payload size of the codebook defining "a retransmission response applied to the third response" is determined based on a field included in information for scheduling the first resource or information for scheduling the second resource.

2. A communication method performed by a terminal, comprising the following steps: A receiving step of receiving, from a base station, information on scheduling a first resource for inter-UE direct communication, information on scheduling a second resource for communication with the base station, and data via the second resource; and a sending step, using the first resource to send data to other terminals, The receiving step includes the step of receiving a first response related to retransmission control corresponding to the transmitted data from the other terminal, The communication method further comprises a control step of determining a third response related to retransmission control based on the first response and a second response related to retransmission control corresponding to data passing through the second resource, The sending step includes the step of sending the third response to the base station. The codebook that specifies "the retransmission response to be applied to the third response" is the same as the codebook that specifies "the retransmission response to be applied to the second response", In the case where the codebook defining "a retransmission response applied to the third response" is dynamic, the payload size of the codebook defining "a retransmission response applied to the third response" is determined based on a field included in information for scheduling the first resource or information for scheduling the second resource.

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