Method and apparatus for sending or receiving sidelink feedback in a communication system

Abstract

The present disclosure relates to a communication technology and a system thereof for aggregating a 5G communication system, and the 5G communication system is used to support a higher data transmission rate than a 4G system using IoT technology. The present disclosure can be applied to intelligent services based on 5G communication technology and IoT-related technologies (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail business, security and safety-related services, etc.). In addition, the present disclosure relates to a method for feedback of a hybrid automatic repeat request (HARQ) performed by a terminal and a terminal for performing the method, the method comprising: generating HARQ feedback information for data scheduled for the terminal in at least one time slot; determining the transmission timing of the HARQ feedback information based on the minimum processing time of the physical side link feedback channel PSFCH transmission of the terminal; and sending the HARQ feedback information based on the determined timing; wherein the minimum processing time of the PSFCH transmission is determined based on at least one of the subcarrier spacing, the configuration of the resource pool, and the time interval between the PSSCH and the PSFCH.

Description

Technical Field

[0001] The present invention relates to a communication system, and more particularly to a method and apparatus for transmitting feedback for data transmission via a side link. More specifically, the present disclosure relates to a method for configuring a HARQ-ACK codebook, a method for determining feedback information to be sent, a method for determining the timing of feedback transmission, and a method and apparatus for transmitting a sidelink physical feedback channel including feedback when data is transmitted via a side link and a receiving terminal transmits HARQ-ACK information of the data to a terminal that has transmitted the data. The present disclosure can be applied to the case where HARQ-ACK feedback is activated between a transmitting terminal and a receiving terminal in sidelink communication. Background Art

[0002] In order to meet the demand for increased wireless data services since the deployment of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "post-4G networks" or "post-LTE systems". 5G communication systems are considered to be implemented in higher frequency (mmWave) bands, such as the 60GHz band, in order to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, in 5G communication systems, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technology are discussed. In addition, in 5G communication systems, development of system network improvements based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communications, wireless backhaul, mobile networks, collaborative communications, coordinated multi-point (CoMP), receiving-end interference elimination, etc. is underway. In 5G systems, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) as advanced coding modulation (ACM), filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies have been developed.

[0003] The Internet is a human-centered connectivity network where humans generate and consume information, and is now developing into the Internet of Things (IoT), where distributed entities such as things exchange and process information without human intervention. The Internet of Everything (IoE) is an Internet where IoT technology and big data processing technology are combined through connection with cloud servers. Technology elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology" and "security technology" have recently been studied for IoT implementation, sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC), etc. This IoT environment can provide smart Internet technology services that create new value for human life by collecting and analyzing data generated between connected things. Through the integration and combination between existing information technology (IT) and various industrial applications, IT can be applied to various fields, including smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, health care, smart devices and advanced medical services.

[0004] In line with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine type communications (MTC), and machine-to-machine (M2M) communications can be implemented through beamforming, MIMO, and array antennas. Cloud radio access networks (RANs) as an application of the above-mentioned big data processing technologies can also be considered as an example of the convergence between 5G technologies and IoT technologies.

[0005] The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made and no assertion is made as to whether any of the above might be applicable as prior art with respect to the present disclosure. Summary of the invention

[0006] [Technical issues]

[0007] In a wireless communication system, more specifically, in a new radio (NR) system, according to data transmission from a transmitting terminal to a receiving terminal, the receiving terminal may receive data and then send HARQ-ACK feedback information about the corresponding data to the transmitting terminal. For example, in downlink data transmission, the terminal sends HARQ-ACK feedback information of data sent from the base station to the base station via configured resources. In sidelink data transmission, the receiving terminal may send HARQ-ACK feedback to the transmitting terminal. HARQ-ACK feedback may be used as information determined by the transmitting terminal for retransmission. A physical sidelink feedback channel (PSFCH) may be used as a physical channel, which is used by the receiving terminal to send HARQ-ACK feedback. Since all time slots of the side link may not include resources via which PSFCH is sent, the receiving terminal needs to send HARQ-ACK feedback information for multiple segments of data (physical sidelink shared channel (PSSCH)) via one PSFCH. In this case, the present disclosure provides a method and apparatus for sending HARQ-ACK feedback in device-to-device communication.

[0008] [Solution]

[0009] One embodiment may provide a method for feedback of hybrid automatic repeat request (HARQ) by a terminal, the method comprising: generating HARQ feedback information for data scheduled by the terminal in at least one time slot; determining the transmission timing of the HARQ feedback information based on the minimum processing time of the physical side link feedback channel PSFCH transmission of the terminal; and sending the HARQ feedback information based on the determined timing; wherein the minimum processing time of the PSFCH transmission is determined based on at least one of the subcarrier spacing, the configuration of the resource pool, and the time interval between the PSSCH and the PSFCH.

[0010] In addition, an embodiment may provide a terminal for feedback of hybrid automatic repeat request (HARQ), the terminal comprising: a transceiver; and a controller, which is configured to: generate HARQ feedback information for data scheduled by the terminal in at least one time slot; determine the transmission timing of the HARQ feedback information based on the minimum processing time of the physical side link feedback channel PSFCH transmission of the terminal; and send the HARQ feedback information based on the determined transmission timing via the transceiver, wherein the minimum processing time of the PSFCH transmission is determined based on at least one of the subcarrier spacing, the configuration of the resource pool, and the time interval between the PSSCH and the PSFCH.

[0011] [Beneficial Effects of the Invention]

[0012] An embodiment may provide a method and apparatus for sending or receiving sidelink feedback in a communication system. In addition, according to an embodiment, a receiving terminal may send HARQ-ACK feedback to a transmitting terminal via a sidelink. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals represent like parts:

[0014] Figure 1 The basic structure of the time-frequency domain is shown, which is the radio resource domain for transmitting data or control channels in the downlink or uplink of the NR system;

[0015] Figure 2 An example of allocating frequency and time resources for information transmission in an NR system is shown;

[0016] Figure 3A Another example of allocating frequency and time resources for information transmission in an NR system is shown;

[0017] Figure 3B A process in which one transport block is divided into a plurality of code blocks and CRC is added thereto according to an embodiment is shown;

[0018] Figure 4 An example of one-to-one communication between two terminals 401 and 405 is shown, that is, unicast communication is performed through a side link;

[0019] Figure 5 An example of multicast communication in which a terminal sends common data to multiple terminals via a side link is shown;

[0020] Figure 6 A process is shown in which a terminal that has received common data by multicast sends information related to the success or failure of data reception to a terminal that has sent data;

[0021] Figure 7 Aspects of mapping synchronization signals and physical broadcast channels of NR systems in the frequency and time domains are shown;

[0022] Figure 8 The symbols in the time slot to which a single SS / PBCH block is mapped are shown;

[0023] Fig. 9 shows the symbols through which the SS / PBCH blocks may be transmitted according to the subcarrier spacing;

[0024] Fig.10 is another diagram illustrating symbols through which SS / PBCH blocks may be transmitted according to subcarrier spacing;

[0025] Fig.11 An example of a resource pool is shown, which is defined as a set of resources in the time and frequency domains for transmission or reception over a sidelink;

[0026] Fig.12 An example of a method for allocation of scheduled resources (Mode 1) via a sidelink is shown;

[0027] Fig.13 An example of a method for UE autonomous resource allocation (Mode 2) over a sidelink is shown;

[0028] Fig.14A An example of a method for configuring a sensing window A for UE autonomous resource allocation (mode 2) for a sidelink is shown;

[0029] Fig. 14B An example of a method for configuring sensing window B for UE autonomous resource allocation (mode 2) for sidelink is shown;

[0030] Fig. 14C is an example of a method for configuring sensing window A and sensing window B for UE autonomous resource allocation (mode 2) of a side link;

[0031] Fig.15A A Mode 1 method is shown, which is a method for receiving scheduling information from a base station and performing sidelink data transmission;

[0032] Fig. 15B A Mode 2 method is shown, which is a method for performing sidelink data transmission without receiving scheduling information from a base station;

[0033] Fig.16A An example of a mapping structure of a physical channel mapped to one time slot via a side link is shown;

[0034] Fig. 16B An example of configuring resources capable of transmitting or receiving a PSFCH in each time slot is shown;

[0035] Fig. 16C An example is shown in which resources are configured to transmit or receive PSFCH every 4 time slots;

[0036] Fig.16D A case is shown in which UE 1 and UE 2 are connected via unicast or multicast communication through a side link to perform signal transmission / reception and a PSFCH needs to be transmitted through the same time slot in order to transmit HARQ-ACK feedback for a PSSCH transmitted by each of UE 1 and UE 2;

[0037] Fig.16EA case is shown in which UE 1 is connected to UE 2 and UE 3 respectively through unicast or multicast communication to perform signal transmission / reception and needs to transmit two PSFCHs through the same time slot in order to transmit HARQ-ACK feedback for the PSSCH transmitted by each of UE 2 and UE 3 to UE 1;

[0038] Fig.17 An example of a terminal determining a time slot for sending HARQ-ACK feedback is shown;

[0039] Fig.18 shows the maximum number of HARQ-ACK feedback bits that need to be sent by the terminal through one PSFCH;

[0040] Fig.19 Another example is shown in which a terminal determines a time slot for sending HARQ-ACK feedback;

[0041] Fig. 20 Another example of a terminal determining a time slot for sending HARQ-ACK feedback is shown;

[0042] Fig.21 Another example of a terminal determining a time slot for sending HARQ-ACK feedback is shown;

[0043] Fig. 22 Another example of a terminal determining a time slot for sending HARQ-ACK feedback is shown;

[0044] Fig.23 An example of configuring a physical time slot index and a logical time slot index of a time slot included in a resource pool in a physical time slot according to a resource pool configuration is shown;

[0045] Fig.24 A method for sending feedback information by including the feedback information in the PSFCH is shown according to whether the resource pool includes a physical time slot and the position of the time slot configured by the PSFCH resource;

[0046] Fig.25A A method is shown in which a minimum unit of frequency resource allocation for PSSCH is determined based on N, which is a time slot period in a resource pool for which PSFCH resources are configured;

[0047] Fig.25B A method is shown in which a minimum unit of frequency resource allocation for PSSCH is determined based on N, which is a time slot period in a resource pool for which PSFCH resources are configured;

[0048] Fig.25CA method is shown in which a minimum unit of frequency resource allocation for a PSSCH is determined based on N, which is a time slot period in a resource pool for which PSFCH resources are configured;

[0049] Fig.26 An example of a slot structure in the case of transmitting a CSI-RS and an example of a slot structure in the case of reporting CSI information are shown;

[0050] Fig. 27 is a block diagram showing an internal structure of a terminal according to an embodiment; and

[0051] Fig.28 is a block diagram showing an internal structure of a base station according to an embodiment. DETAILED DESCRIPTION

[0052] Before proceeding to the following detailed description, it may be helpful to set forth definitions of certain words and phrases used in this patent document: the terms "include" and "comprising" and their derivatives mean including but not limited to; the term "or" is inclusive, referring to and / or; the phrases "associated with" and "associated with" and their derivatives may mean including, included, interconnected with, containing, contained within, connected to or connected with, coupled to or coupled with, communicable with, cooperating with, interleaved, juxtaposed, adjacent, bound to or bound with, having, having the property of, etc.; and the term "controller" means any device, system, or part thereof that controls at least one operation, such device may be implemented in hardware, firmware, or software, or a combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely.

[0053] In addition, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed by a computer-readable program code and is contained in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, processes, functions, objects, classes, instances, related data, or parts thereof suitable for implementation in appropriate computer-readable program codes. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as a read-only memory (ROM), a random access memory (RAM), a hard drive, a compact disc (CD), a digital video disc (DVD), or any other type of memory. "Non-transitory" computer-readable media excludes wired, wireless, optical or other communication links that transmit temporary electrical signals or other signals. A non-transitory computer-readable medium includes a medium that can permanently store data, and a medium that can store data and then rewrite data, such as a rewritable optical disc or an erasable storage device.

[0054] Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most, instances, such definitions apply to past as well as future tenses of such defined words and phrases.

[0055] Discussed below Figures 1 to 28 The various embodiments used to describe the principles of the present disclosure in this patent document are merely exemplary and should not be interpreted in any way to limit the scope of the present disclosure. Those skilled in the art will appreciate that the principles of the present invention can be implemented in any suitably arranged system or device.

[0056] A new radio access technology NR is designed, which is a new 5G communication, so that various services can be freely multiplexed on time and frequency resources, so that waveforms / digits, reference signals, etc. can be dynamically or freely allocated according to the needs of the corresponding services. In order to provide the best service to the terminal in wireless communication, it is important to send the best data based on the measurement of channel quality and interference amount, and therefore, accurate channel state measurement is necessary. However, unlike 4G communication in which the channel and interference characteristics do not change significantly according to the frequency resources, the 5G channel has channel and interference characteristics that change significantly according to the service, and as a result, it is necessary to support a subset of frequency resource groups (FRGs) that can measure the channel and interference characteristics separately. Meanwhile, in the NR system, a supported service can be classified into categories such as enhanced mobile broadband (eMBB), massive machine type communication (mMTC), ultra-reliable and low latency communication (URLLC), etc. eMBB can be considered as a service for high-speed transmission of high-capacity data, mMTC can be considered as a service for terminal power minimization and access of multiple terminals, and URLLC can be considered as a service for high reliability and low latency. Different requirements can be applied depending on the type of service applied to the terminal.

[0057] As described above, a variety of services can be provided to users in a communication system, and a method capable of providing each service within the same time interval according to characteristics so as to provide a variety of services to users and an apparatus using the method are required.

[0058] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0059] When describing the exemplary embodiments of the present disclosure, descriptions related to the technical contents known in the technical field to which the present disclosure belongs and not directly related to the present disclosure will be omitted. Omitting unnecessary descriptions is intended to prevent the main idea of ​​the present disclosure from being obscured so as to convey the main idea more clearly.

[0060] For the same reason, in the accompanying drawings, some elements may be exaggerated, omitted or schematically shown. In addition, the size of each element does not fully reflect the actual size. In the accompanying drawings, the same or corresponding elements have the same reference numerals.

[0061] By referring to the embodiments described in detail below in conjunction with the accompanying drawings, the advantages and features of the present disclosure and the ways to achieve them will be apparent. However, the present disclosure is not limited to the embodiments set forth below, but can be implemented in various different forms. The following embodiments are provided only to fully disclose the present disclosure and to inform those skilled in the art of the scope of the present disclosure, and the present disclosure is limited only by the scope of the appended claims. Throughout the specification, the same or similar reference numerals represent the same or similar elements.

[0062] Here, it will be understood that each box in the flowchart and the combination of boxes in the flowchart can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to produce a machine so that the instructions executed by the processor of the computer or other programmable data processing device generate a device for realizing the function specified in one or more flowchart boxes. These computer program instructions can also be stored in a computer-available or computer-readable memory, which can guide the computer or other programmable data processing device to run in a particular way, so that the instructions stored in the computer-available or computer-readable memory generate products including instruction devices that realize the function specified in the flowchart box (one or more). The computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are performed on a computer or other programmable device, thereby generating a computer-implemented process so that the instructions executed on the computer or other programmable device provide steps for realizing the function specified in one or more flowchart boxes.

[0063] In addition, each block of the flow chart may represent a module, segment or portion of a code including one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions recorded in the blocks may not occur in the order shown. For example, two blocks shown in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order, depending on the functions involved.

[0064] As used herein, "unit" refers to a software element or hardware element that performs a predetermined function, such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC). However, "unit" does not always have a meaning limited to software or hardware. "Unit" can be constructed to be stored in an addressable storage medium or executed on one or more processors. Therefore, "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, processes, functions, attributes, processes, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays and parameters. The elements and functions provided by "unit" can be combined into a smaller number of elements, "unit" or divided into a larger number of elements or "units". In addition, elements or "units" can be implemented as reproducing on one or more CPUs in a device or a secure multimedia card. In addition, in one embodiment, "unit" can include one or more processors.

[0065] Wireless communication systems have evolved into broadband wireless communication systems that provide high-speed and high-quality packet data services beyond the originally provided voice-based services according to communication standards such as High Speed ​​Packet Access (HSPA) of 3GPP, Long Term Evolution (LTE) or Evolved Universal Terrestrial Radio Access (E-UTRA), LTE Advanced (LTE-A), High Speed ​​Packet Data (HRPD) of 3GPP2, Ultra Mobile Broadband (UMB), and IEEE's 802.16e. In addition, communication standards of 5G or New Radio (NR) are being developed as 5G wireless communication systems.

[0066] As a representative example of a broadband wireless communication system, the NR system adopts an orthogonal frequency division multiplexing (OFDM) scheme in the downlink (DL) and uplink (UL). More specifically, the NR system uses a cyclic prefix OFDM (CP-OFDM) scheme in the downlink (DL) and a discrete Fourier transform spread OFDM (DFT-S-OFDM) scheme as well as CP-OFDM in the uplink (UL). The term "uplink" refers to a wireless link used to send data or control signals from a terminal (user equipment (UE) or mobile station (MS)) to a base station (gNode B or BS), while the term "downlink" refers to a wireless link used to send data or control signals from a base station to a terminal. In the above-mentioned multiple access scheme, the time-frequency resources used to carry data or control information are allocated and operated in a manner to prevent resource overlap, that is, to establish orthogonality between users so as to identify the data or control information of each user.

[0067] If a decoding failure occurs in the initial transmission, the NR system adopts a hybrid automatic repeat request (HARQ) scheme to retransmit the corresponding data in the physical layer. The HARQ scheme is designed to operate in such a way that if the receiver cannot accurately decode the data, the receiver sends information indicating the decoding failure, i.e., a negative acknowledgement (NACK), so that the transmitter can retransmit the corresponding data in the physical layer. The receiver can combine the data retransmitted from the transmitter with the previous data that failed to decode, so that the data reception performance can be improved. In addition, if the receiver accurately decodes the data, the receiver sends information (ACK) reporting that the decoding was successfully performed, so that the transmitter sends new data.

[0068] Figure 1 The basic structure of the time-frequency domain is shown, which is the radio resource domain for sending data or control channels in the downlink or uplink of the NR system.

[0069] Reference Figure 1, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The minimum transmission unit in the time domain is the OFDM symbol, and Nsymb OFDM symbols 102 can be collected to configure one time slot 106. The length of a subframe can be defined by 1.0ms, and a radio frame 114 can be defined by 10ms. The minimum transmission unit in the frequency domain is a subcarrier, and the bandwidth of the entire system transmission bandwidth can be configured by a total of NBW subcarriers 104.

[0070] In the time-frequency domain, the basic unit of resources is a resource element (RE) 112, and the RE can be represented by an OFDM symbol index and a subcarrier index. A resource block (RB or physical resource block (PRB)) 108 is defined by Nsymb consecutive OFDM symbols 102 in the time domain and NRB consecutive subcarriers 110 in the frequency domain. Therefore, one RB 108 is configured by Nsymb×NRB number of REs 112. Typically, the minimum transmission unit of data is the unit of RB. In an NR system, typically, Nsymb is 14, NRB is 12, and NBW and NRB are proportional to the bandwidth of the system transmission band. In addition, the data rate can be increased in proportion to the number of RBs scheduled to the terminal.

[0071] In the case where the downlink and uplink of the FDD system are divided by frequency and operate in the NR system, the downlink transmission bandwidth and the uplink transmission bandwidth may be different from each other. The channel bandwidth may indicate the RF bandwidth corresponding to the system transmission bandwidth. and respectively show a part of the correspondence between the system transmission bandwidth, subcarrier spacing and channel bandwidth in frequency bands below 6 GHz and above 6 GHz defined in the NR system. For example, in an NR system with a channel bandwidth of 100 MHz and a subcarrier spacing of 30 kHz, the transmission bandwidth may include 273 RBs. In the following Tables 1 and 2, N / A may indicate a bandwidth-subcarrier combination that is not supported by the NR system.

[0072] [Table 1]: Configuration of frequency range 1 (FR1)

[0073]

[0074] [Table 2]: Configuration of frequency range 2 (FR2)

[0075]

[0076] The frequency range in the NR system can be divided and defined by FR1 and FR2, as shown in Table 3 below.

[0077] [Table 3]

[0078] Frequency range specification Corresponding frequency range FR1 450MHz-7125MHz FR2 24250MHz-52600MHz

[0079] In the above description, the ranges of FR1 and FR2 may be applied differently. For example, the frequency range of FR1 may be changed from 450 MHz to 6000 MHz.

[0080] In the NR system, scheduling information for downlink data or uplink data can be sent from the base station to the terminal through downlink control information (DCI). DCI is defined according to various formats, and each format can be determined according to whether the DCI is scheduling information for uplink data (UL grant) or scheduling information for downlink data (DL grant), whether the DCI is a compact DCI with a small amount of control information, whether spatial multiplexing using multiple antennas is applied, and whether the DCI is used for power control. For example, DCI format 1-1, which is scheduling control information (DL grant) for downlink data, may include at least one of the following control information.

[0081] - A carrier indicator indicating the frequency carrier on which the transmission is performed.

[0082] - A DCI format indicator, which is an indicator that distinguishes whether the corresponding DCI is for downlink or uplink.

[0083] - A bandwidth part indicator indicating the BWP in which the transmission is performed.

[0084] - Frequency domain resource allocation, which indicates RBs in the frequency domain allocated for data transmission. The resources to be expressed are determined according to the system bandwidth and the resource allocation method.

[0085] - Time domain resource allocation, which indicates the OFDM symbols of the time slots from which the data related channels are transmitted.

[0086] - VRB to PRB mapping, which indicates the mapping scheme between virtual RB (VRB) index and physical RB (PRB) index.

[0087] - Modulation and Coding Scheme (MCS), which indicates a modulation scheme used for data transmission and the size of a transport block as data to be transmitted.

[0088] -HARQ process number, which indicates the number of the HARQ process.

[0089] - A new data indicator, which indicates whether the HARQ transmission is an initial transmission or a retransmission.

[0090] - Redundancy version, which indicates the redundancy version of HARQ.

[0091] - Transmit Power Control (TPC) Command for Physical Uplink Control Channel (PUCCH), which indicates a transmit power control command for PUCCH which is an uplink control channel.

[0092] In the case of data transmission through PDSCH or PUSCH, time domain resource allocation may be transmitted via information about the time slot to which PDSCH / PUSCH is transmitted, the starting symbol position S in the corresponding time slot, and the number of symbols to which PDSCH / PUSCH is mapped L. Here, S may be a relative position from the beginning of the time slot, L may be the number of consecutive symbols, and S and L may be determined based on a start and length indicator value (SLIV) defined as follows.

[0093] if(L-1)≤7then

[0094] SLIV=14·(L-1)+Selse

[0095] SLIV=14·(14-L+1)+(14-1-S)

[0096] where 0<L≤14-S

[0097] The NR system may receive the configuration of a table through RRC configuration, wherein the SLIV value, the PDSCH / PUSCH mapping type, and information about the time slot to which the PDSCH / PUSCH is transmitted are included in one row (for example, the above information may be included in the form of a table). Subsequently, in the time domain resource allocation of the DCI, the base station may send the SLIV value, the PDSCH / PUSCH mapping type, and information about the time slot to which the PDSCH / PUSCH is transmitted to the terminal by indicating the index value in the table configured as above.

[0098] In the NR system, the PDSCH mapping type is defined by type A and type B. In PDSCH mapping type A, the first symbol in the DMRS symbol is located at the second or third OFDM symbol in the time slot. In PDSCH mapping type B, the first symbol in the DMRS symbol is located at the first OFDM symbol in the time domain resources allocated via PUSCH transmission.

[0099] The DCI may be subjected to channel coding and modulation processing, and then may be transmitted via a physical downlink control channel (PDCCH) as a downlink physical control channel. In the present disclosure, transmission of control information via a PDCCH or a PUCCH may be represented as transmission of a PDCCH or a PUCCH. Similarly, transmission of data via a PUSCH or a PDSCH may be represented as transmission of a PUSCH or a PDSCH.

[0100] Typically, the DCI is scrambled with a specific radio network temporary identifier (RNTI) (or terminal identifier), a cyclic redundancy flag (CRC) is added to it for each terminal individually, and channel coding is performed, thereby configuring and transmitting each independent PDCCH. The PDCCH is mapped and transmitted in the control resource set (CORESET) configured for the terminal.

[0101] Downlink data may be transmitted through a physical downlink shared channel (PDSCH) used as a physical channel for downlink data transmission. The PDSCH may be transmitted after a control channel transmission interval, and scheduling information in the frequency domain (e.g., a specific mapping position and a modulation scheme) may be determined based on the DCI transmitted through the PDCCH.

[0102] Through the MCS included in the control information in the DCI, the base station can inform the terminal of the modulation scheme applied to the PDSCH to be transmitted, and the size of the data to be transmitted (transport block size (TBS)). In one embodiment, the MCS can be configured by 5 bits or more or less. Before applying channel coding for error correction to the data, the TBS corresponds to the size of the data (transport block, TB) that the base station wishes to transmit.

[0103] In the present disclosure, a transport block (TB) may include a medium access control (MAC) header, a MAC control element (CE), one or more MAC service data units (SDUs), and padding bits. According to another embodiment, a TB may indicate a data unit discarded from the MAC layer to the physical layer, or a MAC protocol data unit (MAP PDU).

[0104] The modulation schemes supported by the NR system are quadrature phase shift keying (QPSK), 16 quadrature amplitude modulation (16QAM), 64QAM, and 256QAM, and the modulation orders (Qm) of QPSK, 16QAM, 64QAM, and 256QAM correspond to 2, 4, 6, and 8, respectively. That is, 2 bits per symbol in the case of QPSK modulation, 4 bits per symbol in the case of 16QAM modulation, 6 bits per symbol in the case of 64QAM modulation, and 8 bits per symbol in the case of 256QAM modulation can be transmitted.

[0105] Figure 2 An aspect of allocating multiple pieces of data in frequency-time resources as services considered in a 5G or NR system and for eMBB, URLLC, and mMTC is shown. Figure 3A An aspect of allocating multiple pieces of data in frequency-time resources as services considered in a 5G or NR system and for eMBB, URLLC, and mMTC is shown.

[0106] Reference Figure 2 and Figure 3A , a scheme can be identified in which frequency and time resources are allocated for performing information transmission in each system.

[0107] first, Figure 2 An example of allocating multiple pieces of data for eMBB, URLLC, and mMTC in the entire system frequency bandwidth 200 is shown. In the middle of allocating eMBB data 201 and mMTC data 209 in a specific frequency bandwidth and performing transmission thereof, if URLLC data 203, 205, and 207 are generated and it is necessary to transmit URLLC data 203, 205, and 207, URLLC data 203, 205, and 207 may be transmitted without clearing the portion to which eMBB data 201 and mMTC data 209 have been allocated and not transmitting the portion. Since URLLC needs to reduce the delay time in the middle of performing the above-mentioned services, URLLC data 203, 205, and 207 may be allocated to the portion to which eMBB data is allocated in resource 201, so that it can be transmitted. Of course, in the case where URLLC data 203, 205, and 207 are additionally allocated and transmitted in the resource to which eMBB data is allocated, eMBB data may not be transmitted in overlapping frequency-time resources, and thus the transmission performance of eMBB data may be reduced. That is, in the above situation, eMBB data transmission failure due to URLLC data allocation may occur.

[0108] Figure 3A An example of transmitting services and data in each of subbands 302, 304, and 306 obtained by dividing the entire system frequency bandwidth 300 is shown. Information associated with the subband configuration may be predetermined and may be transmitted to the terminal by the base station via higher layer signaling. Alternatively, information associated with the subband may be arbitrarily divided by the base station or the network node, and services may be provided to the terminal without transmitting separate subband configuration information. Figure 3A One aspect is shown where subband 302 is used for transmission of eMBB data, subband 304 is used for transmission of URLLC data, and subband 306 is used for transmission of mMTC data.

[0109] Throughout the embodiments, the length of a transmission time interval (TTI) for URLLC data transmission may be shorter than the length of a TTI for eMBB data or mMTC data transmission. In addition, a response to information related to URLLC data may be sent faster than eMBB data or mMTC data, and thus information transmission or reception with low latency may be performed. The structures of the physical layer channels used to transmit the above three types of services or data may be different from each other. For example, at least one of the length of the transmission time interval (TTI), the allocation unit of frequency resources, the structure of the control channel, and the data mapping method may be different.

[0110] In the above, three types of services and three types of data are described, but there may be more types of services and corresponding data, and in this case, the content of the present disclosure may be applied.

[0111] In order to explain the methods and devices proposed in the present disclosure, the terms "physical channel" and "signal" in the NR system may be used. However, the details of the present invention may be applied to wireless communication systems other than the NR system.

[0112] Hereinafter, an embodiment of the present disclosure will be described in detail in conjunction with the accompanying drawings. In addition, when describing the present invention, if it is determined that a detailed description of the relevant function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, the terms to be described later are terms defined in consideration of the functions in the present disclosure, which may vary according to the intention or practice of the user or operator. Therefore, they should be defined based on the contents of the full text of this specification. In the following, a side link (SL) refers to a signal transmission / reception path between a terminal and a terminal, which can be used interchangeably with a PC5 interface. In the following, a base station is a subject that performs resource allocation of a terminal, and may be a base station that supports V2X communication and general cellular communication, or a base station that supports only V2X communication. That is, a base station may represent an NR base station (gNB), an LTE base station (eNB), or a road address unit (RSU) (or a fixed station). The terminal may include a general user equipment, a mobile station, and a vehicle supporting vehicle-to-vehicle communication (vehicle-to-vehicle, V2V), a vehicle supporting vehicle-to-pedestrian (V2P), a pedestrian handset (e.g., a smart phone), a vehicle supporting vehicle-to-network communication (V2N), a vehicle supporting vehicle-to-infrastructure communication (V2I), an RSU equipped with a terminal function, an RSU equipped with a base station function, or an RSU equipped with a portion of a base station function and a portion of a terminal function. In the present disclosure, a downlink (DL) is a radio transmission path for a signal sent by a base station to a terminal, and an uplink (UL) represents a radio transmission path for a signal sent by a terminal to a base station. In addition, although the NR system will be used as an example to describe the embodiment below, the embodiment may be applied to other communication systems with similar technical backgrounds or channel types. In addition, as determined by those skilled in the art, the embodiment may be applied to other communication systems by some modifications within the scope that do not significantly deviate from the scope of the present disclosure.

[0113] In the present disclosure, the terms "physical channel" and "signal" may be used interchangeably with data or control signals. For example, PDSCH is a physical channel through which data is transmitted, but in the present disclosure, PDSCH may be referred to as data.

[0114] Hereinafter, in the present disclosure, higher signaling is a signal sending method of sending a signal from a base station to a terminal using a downlink data channel of a physical layer, or a signal sending method of sending a signal from a terminal to a base station using an uplink data channel of a physical layer, and the higher signaling may be referred to as RRC signaling or a MAC control element (CE).

[0115] The following embodiments provide a method and apparatus for performing transmission or reception of HARQ-ACK feedback, wherein the HARQ-ACK feedback is used for data transmission between a base station and a terminal or between terminals. This embodiment may be a case where feedback is sent from one terminal to multiple terminals, or a case where feedback is sent from one terminal to one terminal. Alternatively, this embodiment may be a case where feedback is sent from a base station to multiple terminals. However, the present disclosure may be applicable to various situations and is not limited thereto.

[0116] Figure 3B An embodiment is shown in which one transport block is divided into multiple code blocks and a CRC is added thereto.

[0117] Reference Figure 3B , CRC 303 can be added to the last part or the first part of a transport block (TB) 301 so as to be sent in the uplink or downlink. CRC 303 may have 16 bits, 24 bits or a fixed number of bits, or may have a variable number of bits depending on channel conditions, and may be used to determine whether channel coding is successful. TB 301 and the block to which CRC 303 is added may be divided into a plurality of code blocks (CB) 307, 309, 311 and 313 (represented by reference numeral 305). The divided code blocks may have a predetermined maximum size, and in this case, the size of the last code block 313 may be smaller than the size of the other code blocks 307, 309 and 311. This is given as an example only, and according to another example, the last code block 313 may include a length adjusted to be the same as the length of the other code blocks 307, 309 and 311 by adding zero, a random value or 1 to the last code block 313. CRC 317, 319, 321, and 323 may be added to code blocks 307, 309, 311, and 313 (indicated by reference numeral 315), respectively. The CRC may include 16 bits, 24 bits, or a fixed number of bits, and may be used to determine whether channel coding is successful.

[0118] CRC 303 can be generated using TB 301 and a cyclic generator polynomial, and the cyclic generator polynomial can be defined in various ways. For example, if a 24-bit CRC and L=24 are assumed, and for TB data a 0 , a 1 , a 2 , a 3 , ..., a A-1 and CRCp 0 , p 1 , p 2 , p 3 ,…,p L-1 , the cycle generator polynomial g CRC24A (D)=[D 24 +D23 +D 18 D 17 +D 14 +D 11 +D 10 +D 7 +D 6 +D 5 +D 4 +D 3 +D+1] can be obtained by adding a 0 D A+23 +a 1 D A+22 +…+a A-1 D 24 +p 0 D 23 +p 1 D 22 +…+p 22 D 1 +p 23 Divide by g CRC24A (D) and the remainder is 0, and we can determine p 0 , p 1 , p 2 , p 3 , ..., p L-1 In the above example, it is assumed that the CRC length “L” is 24 as an example, but the CRC length “L” may be determined to have different lengths, such as 12, 16, 24, 32, 40, 48, 64, etc.

[0119] Through this process, CRC is added to TB, and the TB with CRC added thereto can be divided into N CBs 307, 309, 311, and 313. CRC 317, 319, 321, and 423 can be added to each of the divided CBs 307, 309, 311, and 313 (indicated by reference numeral 315). The CRC added to the CB can have a different length from the CRC added to the TB, or a different cyclic generator polynomial can be used. In addition, the CRC 303 added to the TB and the CRC 317, 319, 321, and 323 added to the code block can be omitted according to the type of channel code to be applied to the code block. For example, if an LDPC code other than a turbo code is applied to a code block, the CRC 317, 319, 321, and 323 inserted for each code block can be omitted.

[0120] However, even if LDPC is applied, CRC 317, 319, 321, and 323 may be added to the code block as it is. Furthermore, even if polar codes are used, CRC may be added or omitted.

[0121] As above Figure 3BAs described in , the maximum length of one code block is determined according to the type of channel coding applied to a TB to be transmitted, and the TB and the CRC added to the TB are divided into code blocks according to the maximum length of the code block.

[0122] In a conventional LTE system, a CRC of a CB is added to a divided CB, data bits and the CRC of the CB are encoded using a channel code, thereby determining coded bits, and the number of bits for performing a predetermined rate matching with each coded bit can be determined.

[0123] The TB size in the NR system can be calculated by the following operations.

[0124] Operation 1: Calculate the number N′ of REs allocated to PDSCH mapping in one PRB in the allocated resources RE .

[0125] Here, N′ RE Can be Here, is 12, and It can indicate the number of OFDM symbols allocated to PDSCH. is the number of REs in one PRB occupied by DMRSs of the same Code Division Multiple Access (CDM) group. is the number of REs occupied by overhead in one PRB configured via higher signaling, and can be configured as 0, 6, 12, or 18. Hereinafter, the total number of REs allocated to PDSCH, N RE can be calculated. RE By min(156,N′ RE )·n PRB Calculate, and n PRB Indicates the number of PRBs allocated to the terminal.

[0126] Operation 2: Number of temporary information bits N info Can be N RE *R*Q m *v calculation. Here, R is the code rate, Qm is the modulation order, and the value information can be transmitted using the MCS bit field and a table predefined in the control information. Also, v is the number of allocated layers. If N info ≤3824, then TBS can be calculated by operation 3 as follows. Otherwise, TBS can be calculated by operation 4.

[0127] Operation 3: N′ info It can be calculated by the following formula: and TBS can be determined as a value equal to or greater than N' in Table 4a below. infoThe value closest to N′ info .

[0128] [Table 4a]

[0129] index TBS index TBS index TBS index TBS 1 24 31 336 61 1288 91 3624 2 32 32 352 62 1320 92 3752 3 40 33 368 63 1352 93 3824 4 48 34 384 64 1416 5 56 35 408 65 1480 6 64 36 432 66 1544 7 72 37 456 67 1608 8 80 38 480 68 1672 9 88 39 504 69 1736 10 96 40 528 70 1800 11 104 41 552 71 1864 12 112 42 576 72 1928 13 120 43 608 73 2024 14 128 44 640 74 2088 15 136 45 672 75 2152 16 144 46 704 76 2216 17 152 47 736 77 2280 18 160 48 768 78 2408 19 168 49 808 79 2472 20 176 50 848 80 2536 21 184 51 888 81 2600 22 192 52 928 82 2664 23 208 53 984 83 2728 24 224 54 1032 84 2792 25 240 55 1064 85 2856 26 256 56 1128 86 2976 27 272 57 1160 87 3104 28 288 58 1192 88 3240 29 304 59 1224 89 3368 30 320 60 1256 90 3496

[0130] Operation 4: N info It can be calculated by the following formula: and TBS can be info Here, "C" represents the number of code blocks.

[0131] [Beginning of pseudocode 1]

[0132]

[0133] [End of Pseudocode 1]

[0134] In the NR system, if a CB is input to the LDPC encoder, parity bits may be added to the CB, and the CB to which the parity bits are added may be output. The number of parity bits may differ according to the LDPC base graph. The method for sending all parity bits generated by LDPC encoding for a specific input may be referred to as full buffer rate matching (FBRM), and the method for limiting the number of parity bits that can be sent may be referred to as limited buffer rate matching (LBRM). If resources are allocated for data transmission, the output of the LDPC encoder is made into a circular buffer, and the bits of the buffer are repeatedly sent as many times as the allocated resources, and the length of the circular buffer may be referred to as Ncb. If the number of bits of all LDPC codewords generated by LDPC encoding is N, Ncb is equal to N in the FBRM method. In the LBRM method, N cb represents min(N, N ref ), N ref Given by: And R LBRM can be determined as 2 / 3. In the method for obtaining the above TBS, TBS LBRM represents the maximum number of layers supported by the terminal in the corresponding cell, which corresponds to the maximum modulation order configured for the terminal in the cell. In addition, if there is no configured maximum modulation order, TBS is assumed LBRM is 64QAM, and the code rate is assumed to be 948 / 1024, which is the maximum code rate. Assuming N RE =156·n PRB , and we can assume that n PRB n PRB，LBRM , where n PRB，LBRMIt can be given as shown in Table 4b below.

[0135] [Table 4b]

[0136]

[0137] The maximum data rate supported by the terminal in the NR system can be determined by the following <Equation 1>.

[0138] [Equation 1]

[0139]

[0140] In <Equation 1>, J may represent the number of carriers limited by carrier aggregation, R max =948 / 1024, The maximum number of layers that can be represented, It can represent the maximum modulation order, f (j) may represent the scaling index, and μ may represent the subcarrier spacing. The terminal may report f (j) The value of is one of 1, 0.8, 0.75 and 0.4, and μ can be given as shown in Table 4c below.

[0141] [Table 4c]

[0142]

[0143]

[0144] also, is the average OFDM symbol length, can be calculated as and is the maximum number of RBs in BW(j). (j) is an overhead value and may be given as 0.14 in the downlink, 0.18 in the uplink of FR1 (frequency band equal to or less than 6 GHz), 0.08 in the downlink, and 0.10 in the uplink of FR2 (frequency band exceeding 6 GHz). By <Equation 1>, the maximum data rate in the downlink in a cell having a 100 MHz frequency bandwidth at a 30 kHz subcarrier spacing may be calculated by the following .

[0145] [Table 4d]

[0146]

[0147] On the other hand, the actual data rate that the terminal can measure in actual data transmission can be a value obtained by dividing the amount of data by the data transmission time. This can be a value obtained by dividing the TBS by the TTI length in 1TB transmission or by dividing the sum of the TBS by the TTI length in 2TB transmission. For example, as shown in , the maximum actual data rate in the downlink in a cell with a 100MHz frequency bandwidth at a 30kHz subcarrier spacing can be determined based on the number of allocated PDSCH symbols, as shown in below.

[0148] [Table 4e]

[0149]

[0150] The maximum data rate supported by the terminal can be identified by , and the actual data rate according to the allocated TBS can be identified by . At this time, according to the scheduling information, the actual data rate can be greater than the maximum data rate.

[0151] In a wireless communication system, especially in a new radio (NR) system, the data rate that a terminal can support can be agreed upon between a base station and a terminal. The data rate can be calculated using the maximum frequency band, the maximum modulation order, and the maximum number of layers supported by the terminal. However, the calculated data rate may be different from the value calculated based on the transport block size (TBS) and the transmission time interval (TTI) length of the transport block (TB) used for actual data transmission.

[0152] Therefore, a situation may occur in which a TBS greater than a value corresponding to a data rate supported by the terminal itself is allocated to the terminal. To prevent this from happening, there may be a restriction on the TBS that can be scheduled according to the data rate supported by the terminal.

[0153] Figure 4 An example of one-to-one communication (ie, unicast communication) performed between two terminals 401 and 405 through a side link is shown.

[0154] Figure 4An example is shown in which a signal is transmitted from a first terminal 401 to a second terminal 405, and the direction of the signal transmission may be opposite. That is, a signal may be sent from the second terminal 405 to the first terminal 401. Terminals 407 and 409 other than the first terminal 401 and the second terminal 405 may not receive signals exchanged by unicast communication between the first terminal 401 and the second terminal 405. Signal exchange by unicast communication between the first terminal 401 and the second terminal 405 may be performed by mapping in agreed resources between the first terminal 401 and the second terminal 405, or may be performed by scrambling using a value agreed therebetween, mapping of control information, data transmission using mutually configured values, and a process of identifying a unique ID value from each other. The terminal may be a mobile terminal such as a vehicle. For unicast communication, separate control information, physical control channels, and data may be sent.

[0155] Figure 5 An example of a multicast communication 510 is shown, in which one terminal 501 sends common data to multiple terminals 503, 505, 507 and 509 via a side link.

[0156] exist Figure 5 , an example is shown in which the first terminal 501 transmits a signal to other terminals 503, 505, 507, and 509 in the group, and other terminals 511 and 513 not included in the group may not receive the signal transmitted for multicast communication.

[0157] The terminal for sending a signal for multicast communication may correspond to another terminal in the group, and resource allocation for signal transmission may be provided by a base station or a terminal serving as a leader in the group, or may be selected by the terminal itself that has sent the signal. The terminal may be a mobile terminal such as a vehicle. Separate control information, physical control channels, and data may be sent for multicast.

[0158] Figure 6 It shows a process in which the terminals 603, 605, 607 and 609, which have received the common data by multicast, send information on the success or failure of receiving the data to the terminal 601, which has sent the data.

[0159] The information may be information such as HARQ-ACK feedback 611. The terminal may be a terminal having an LTE-based sidelink function or an NR-based sidelink function. If the terminal has only an LTE-based sidelink function, the terminal may not be able to send or receive an NR-based sidelink signal and an NR-based physical channel. In the present disclosure, the sidelink may be used interchangeably with PC5, V2X, or D2D. Figure 5 and 6An example of transmission or reception according to multicast is shown, but the description can also be applied to unicast signal transmission or reception between terminals.

[0160] Figure 7 Aspects of mapping the synchronization signals and physical broadcast channel (PBCH) of the NR system in the frequency and time domain are shown.

[0161] A primary synchronization signal (PSS) 701, a secondary synchronization signal (SSS) 703, and a PBCH are mapped to 4 OFDM symbols, the PSS and the SSS are mapped to 12 RBs, and the PBCH is mapped to 20 RBs. Figure 7 The table in shows that the frequency band of 20 RBs varies according to the subcarrier spacing (SCS). The resource region in which PSS, SSS, and PBCH are transmitted may be referred to as an SS / PBCH block. In addition, the SS / PBCH block may be referred to as an SSB block.

[0162] Figure 8 The symbols in a slot are shown to which a single SS / PBCH block is mapped.

[0163] Reference Figure 8 , an example of a legacy LTE system using a subcarrier spacing of 15 kHz and an NR system using a subcarrier spacing of 30 kHz, and SS / PBCH blocks 811, 813, 815, and 817 of the NR system are designed to be transmitted at positions 801, 803, 805, and 807, and a specific cell reference signal (CRS) that is always transmitted in the LTE system can be avoided at positions 801, 803, 805, and 807. The purpose of the design may be to allow the LTE system and the NR system to coexist in a single frequency band.

[0164] Fig. 9 The symbols to which the SS / PBCH blocks may be transmitted based on the subcarrier spacing are shown.

[0165] refer to Fig. 9 , the subcarrier spacing can be configured as 15kHz, 30kHz, 120kHz, 240kHz, etc., and the position of the symbol of the SS / PBCH block (or SSB block) can be determined according to each subcarrier spacing. Fig. 9 The position of the symbol is shown, by which the SSB block can be sent according to the subcarrier spacing in the symbol within 1ms, and it is not always necessary to send Fig. 9 SSB blocks in the area shown. Therefore, the location of sending SSB blocks can be configured for the terminal through system information or dedicated signaling.

[0166] Fig.10 It is shown that the symbols to which the SS / PBCH blocks can be transmitted according to the subcarrier spacing.

[0167] refer to Fig.10 , the subcarrier spacing can be configured as 15kHz, 30kHz, 120kHz, 240kHz, etc., and the position of the symbol of the SS / PBCH block (or SSB block) can be determined according to each subcarrier spacing. Fig.10 It is shown that the position of the symbol through which the SSB block can be transmitted according to the subcarrier spacing in the symbol within 5ms, and the position of the SSB block can be configured for the terminal through system information or dedicated signaling. In the area where the SS / PBCH block can be transmitted, the SS / PBCH block does not always need to be transmitted, and can be transmitted or not transmitted according to the selection of the base station. Therefore, the position of the SSB block can be configured for the terminal through system information or dedicated signaling.

[0168] In the present disclosure, a sidelink control channel may be referred to as a physical sidelink control channel (PSCCH), and a sidelink shared channel or a sidelink data channel may be referred to as a physical sidelink shared channel (PSSCH). A broadcast channel broadcast together with a synchronization signal may be referred to as a physical sidelink broadcast channel (PSBCH), and a channel for feedback transmission may be referred to as a physical sidelink feedback channel (PSFCH). In order to perform feedback transmission, PSCCH or PSSCH may be used. Depending on the communication system in which the channel is transmitted, the channel may be referred to as LTE-PSCCH, LTE-PSSCH, NR-PSCCH, NR-PSSCH, etc. In the present disclosure, a sidelink may indicate a link between terminals, and a Uu link may indicate a link between a base station and a terminal.

[0169] Fig.11 An example of a resource pool is shown, which is defined as a set of resources in the time and frequency domains for transmission or reception over a sidelink.

[0170] Reference numeral 1110 is an example of explaining the case where the resource pool is allocated non-contiguously in the time domain and the frequency domain. In the present disclosure, the case where the resource pool is allocated non-contiguously in the frequency domain is mainly discussed. However, it should be noted that the resource pool can be allocated continuously in the frequency domain.

[0171] Reference numeral 1120 is an example showing a case where non-contiguous resource allocation is performed in the frequency domain. The resource allocation unit (granularity) in the frequency domain may be a physical resource block (PRB).

[0172] Reference numeral 1121 is an example showing a case where resource allocation is performed in the frequency domain based on a subchannel. A subchannel may be defined by a frequency unit including a plurality of RBs. In other words, a subchannel may be defined as an integer multiple of an RB. Fig.11Reference numeral 1121 shows a case where the size of a subchannel is configured by four consecutive PRBs. Subchannels can be configured to have different sizes, and a single subchannel is typically configured by consecutive PRBs, but does not have to be configured by consecutive PRBs. A subchannel can be a basic unit of resource allocation for a physical sidelink shared channel (PSSCH) or a physical sidelink control channel (PSCCH). Therefore, the size of a subchannel can be configured differently depending on whether the corresponding channel is a PSSCH or a PSCCH. Note that a subchannel, as a term, can be replaced by a resource block group (RBG). The following embodiments describe a method for non-continuously allocating a resource pool in the frequency domain and classifying the resource pool into a plurality of subchannels.

[0173] startRBSubchannel indicated by reference numeral 1122 indicates a start position of a subchannel in the frequency domain in the resource pool.

[0174] Resource blocks are frequency resources belonging to the resource pool of PSSCH in the LTE V2X system and can be determined by:

[0175] -The resource block pool consists of N subCH sub-channels, where N subCH Given by the higher layer parameter numSubchannel.

[0176] - for m = 0, 1, ..., N subCH -1, subchannel m consists of a set of n subCHsize The group of consecutive resource blocks is composed of j=0, 1, ..., n subCHsize -1 has physical resource block number n PRB =n subCHRBstart +m*n subCHsize +j, where n subCHRBstart and n subCHsize Given by the higher layer parameters startRBSubchannel and sizeSubchannel respectively.

[0177] Reference numeral 1130 shows an example of a case where non-continuous resource allocation is performed in the time domain. The unit (granularity) of resource allocation in the time domain may be a time slot. In the present disclosure, the case where resource pools are allocated non-continuously in the time domain is mainly discussed. However, it should be noted that resource pools may be allocated continuously in the time domain.

[0178] startSlot indicated by reference numeral 1131 indicates a start position of a time slot in the time domain in the resource pool.

[0179] Subframe as a time resource of a resource pool belonging to PSSCH in an LTE V2X system This can be determined by the following method.

[0180] -

[0181] - the subframe index is relative to subframe #0 of the radio frame corresponding to SFN0 or DFN0 of the serving cell (described in

[11] ),

[0182] - the set includes all subframes except the following subframe,

[0183] - a subframe in which SLSS resources are configured,

[0184] - If sidelink transmission occurs in a TDD cell, then the downlink subframe and special subframe,

[0185] - The reserved subframe is determined by the following steps:

[0186] 1) From the set of all subframes, except N slss and N dssf The remaining subframes outside the subframe are arranged in ascending order of subframe index. To represent, where N slss is the number of subframes in which SLSS resources are configured within 10240 subframes, and if sidelink transmission occurs in a TDD cell, then N dssf It is the number of downlink subframes and special subframes within 10240 subframes.

[0187] 2) If Then subframe l r (0≤r<(10240-N slss -N dssf )) belongs to the reserved subframe, where m = 0, ..., N reserved -1, and N reserved =(10240-N slss -N dssf )modL bitmap Here, L bitmap is the length of the bitmap and is configured by higher layers.

[0188] - Arrange the subframes in increasing order of subframe index.

[0189] -Use the bitmap associated with the resource pool Where L bitmap is the length of the bitmap and is configured by higher layers.

[0190] - If b k′ = 1, where k′ = k mod L bitmap , then the subframe Belongs to the subframe pool.

[0191] Fig.12 An example of a method for allocating scheduled resources (mode 1) through a side link is shown. Allocation of scheduled resources (mode 1) is a method in which a base station allocates resources for side link transmission to an RRC-connected UE in a dedicated scheduling manner. The allocation method of scheduled resources can be effective for interference management and resource pool management because the base station can manage the resources of the side link.

[0192] exist Fig.12In operation 1205, the UE 1201 camped on receives a side link system information bit (SL SIB) from the base station 1203 in operation 1210. The system information may include resource pool information for transmission or reception, configuration information for sensing operation, information for configuration synchronization, information for inter-frequency transmission or reception, etc. If a data service for V2X is generated in the UE 1201, an RRC connection with the base station 1203 is established in operation 1220. Here, the RRC connection between the UE and the base station may be referred to as Uu-RRC. The process of Uu-RRC connection may be performed before generating data services. In operation 1230, the UE 1201 requests transmission resources that can perform V2X communication with other UEs 1202 from the base station 1203. At this time, the UE 1201 may request transmission resources from the base station by using an RRC message or a MAC CE. Here, as the RRC message, SidelinkUEInformation and UEAssistanceInformation messages may be used. At the same time, the MAC CE may be, for example, a buffer status report MAC CE with a new format (including at least an indicator notifying a buffer status report for V2X communication and information about the size of data buffered for D2D communication). The detailed format and content of the buffer status report used in 3GPP may be understood by referring to the 3GPP standard TS36.321 "E-UTRA MAC Protocol Specification". The base station 1203 allocates V2X transmission resources to the UE 1201 through a dedicated Uu-RRC message. This message may be included in the RRCConnectionReconfiguration message. Resource allocation may be performed using V2X resources through Uu or using resources for PC5 according to the type of service requested by the UE 1201 or according to whether the corresponding link is congested. In order to determine the resources, the UE 1201 may add the logical channel ID (LCID) information or the short range service packet priority (PPPP) of the V2X service to the UEAssistanceInformation or MAC CE and send them. Since the base station 1203 also knows information about resources used by other UEs 1202, the base station may allocate the remaining resource pool among the resources requested by the UE 1201 in operation 1235. In operation 1240, the base station 1203 may instruct the UE 1201 to perform final scheduling via DCI transmission through the PDCCH.

[0193] Next, in the case of broadcast transmission, in operation 1260, UE 1201 broadcasts sidelink control information (SCI) to other UEs 1202 via PSCCH using broadcast transmission without using additional RRC configuration of the sidelink. In addition, in operation 1270, UE 1201 broadcasts data to other UEs 1202 through PSSCH.

[0194] Alternatively, in the case of unicast and multicast transmission, UE 1201 can establish an RRC connection with other UEs one by one. Here, in order to distinguish it from Uu-RRC, the RRC connection between UEs can be referred to as PC5-RRC. Even in the case of multicast communication, PC5-RRC is individually connected between UEs belonging to a group. Fig.12 In the embodiment, PC5-RRC connection 1215 is shown as being performed after operation 1210, but PC5-RRC connection can be performed at any time before operation 1210 or before operation 1260. If an RRC connection between UE and UE is required, in operation 1260, a PC5-RRC connection of a side link is established, and side link control information (SCI) is sent to other UEs 1202 via unicast and multicast transmission through PSCCH. At this time, the multicast transmission of SCI can be interpreted as group SCI. In addition, in operation 1270, the UE sends data to other UEs 1202 via unicast and multicast transmission through PSSCH.

[0195] Fig.13 An example of a method for UE autonomous resource allocation (Mode 2) over the sidelink is shown.

[0196] UE autonomous resource allocation (mode 2) is a method in which the base station provides the sidelink transmit / receive resource pool for V2X as system information, and the UE selects the transmission resource according to a predetermined rule. Resource selection methods may include area mapping, sensing-based resource selection, random selection, etc. The difference is that unlike the allocation method of scheduled resources (mode 1) in which the base station itself participates in resource allocation, in Fig.13 In the V2X communication, the UE 1301 autonomously selects resources based on the resource pool previously received through the system information and transmits data. In V2X communication, the base station 1303 can allocate various types of resource pools (V2V resource pool and V2P resource pool) to the UE 1301. The resource pool may include a resource pool in which the UE autonomously selects an available resource pool after sensing the resources used by other neighboring UEs, and a resource pool in which the UE randomly selects resources from a pre-configured resource pool.

[0197] The UE 1301 camped in operation 1305 receives a side link system information bit (SL SIB) from the base station 1303 in operation 1310. The system information may include resource pool information for transmission or reception, configuration information for sensing operation, information for configuration synchronization, information for inter-frequency transmission or reception, and the like. Fig.12 and Fig.13 The main difference between the operations of Fig.12 In the embodiment, the base station 1203 and the UE 1201 operate in the RRC connected state, and Fig.13 In operation 1330, the base station and the UE may even operate in an idle mode 1320 in which the RRC is not connected. In addition, even in the state in which the RRC is connected, the base station 1303 itself may not participate in resource allocation and allow the UE 1301 to autonomously select transmission resources. Here, the RRC connection between the UE 1301 and the base station 1303 may be referred to as Uu-RRC. If a data service for V2X is generated in the UE 1301, in operation 1330, the UE 1301 selects a resource pool in the time domain / frequency domain according to the configured transmission operation from the resource pool received from the base station 1303 through the system information.

[0198] Next, in the case of broadcast transmission, in operation 1320, UE 1301 may not need an additional RRC configuration with a side link, and in operation 1350, UE 1301 broadcasts side link control information (SCI) via broadcast transmission through PSCCH to other UEs 1302. In addition, in operation 1360, the UE broadcasts data to other UEs 1302 through PSSCH.

[0199] Alternatively, in the case of unicast and multicast transmission, UE 1301 can establish an RRC connection with other UE 1302 on a one-to-one basis. Here, in order to distinguish from Uu-RRC, the RRC connection between UE and UE can be referred to as PC5-RRC. Even in the case of multicast communication, PC5-RRC is individually connected between UEs belonging to a group. The connection can be similar to the connection at the RRC layer in the connection between the base station and the UE in the traditional NR uplink and downlink, and the connection through the side link in the RRC layer connection can be referred to as PC5-RRC. UE capability information for the side link can be exchanged through the PC5-RRC connection, or configuration information necessary for signal transmission or reception can be exchanged. Fig.13In the embodiment, PC5-RRC connection 1315 is shown as being performed after operation 1310, but may be performed at any time before operation 1310 or before operation 1350. If an RRC connection between the UE and the UE is required, a PC5-RRC connection of the side link is established in operation 1340, and side link control information (SCI) is sent to other UEs 1302 via unicast and multicast transmission through PSCCH in operation 1350. At this time, the multicast transmission of SCI may be interpreted as group SCI. In addition, in operation 1360, the UE sends data to other UEs 1302 via unicast and multicast transmission through PSSCH.

[0200] In the present disclosure, a sensing window A and a sensing window B are defined in order to effectively perform sensing in the case where periodic and aperiodic traffic coexist.

[0201] Fig.14A An example of a method for configuring a sensing window A for UE autonomous resource allocation (mode 2) for a sidelink is shown, Fig. 14B An example of a sensing window A for UE autonomous resource allocation (mode 2) for the sidelink is shown, Fig. 14C is an example of a method for configuring sensing window A and sensing window B for UE autonomous resource allocation (mode 2) for sidelink.

[0202] like Fig.14A As shown, in the case where a trigger for transmission resource selection occurs in time slot n (denoted by reference numeral 1401), a sensing window A 1402 may be defined as follows.

[0203] *The sensing window A may be defined as a time slot interval of [n-T0, n-1]. Here, T0 may be determined as a fixed value or may be determined as a configurable value.

[0204] **As an example of a case where T0 is determined as a fixed value, for periodic services, T0 can be represented by 1000*2μ. Alternatively, for non-periodic services, T0 can be configured as a fixed value of 100*2μ. The fixed T0 value of the above example can be changed to another value according to the service characteristics considered, and can be fixed to the same value for periodic and non-periodic services. Here, μ is an index corresponding to numerology and is configured to the following values ​​according to the subcarrier spacing (SCS).

[0205] ***SCS=15kHz,μ=0

[0206] ***SCS=30kHz,μ=1

[0207] ***SCS=60kHz,μ=2

[0208] ***SCS=120kHz,μ=3

[0209] **For the case where the determination of T0 is configurable, the configuration for determination may be indicated by a side link system information bit (SL SIB) or a higher level signaling specific to the UE. If the determination is indicated by SLSIB, the corresponding value may be configured in the resource pool information in the corresponding system information. The case where T0 is configured in the resource pool information indicates that a predetermined T0 is always used in the resource pool.

[0210] *In sensing window A, SCI decoding and sidelink measurements of other UEs can be performed.

[0211] ** Resource allocation information for other UEs and QoS information for packets can be obtained from the SCI received in the sensing window A. Here, the resource allocation information may include a reserved interval for resources. In addition, the QoS information may include waiting time, reliability, the minimum required communication range of the transmitted service, and priority information according to data rate requirements. The location information of other UEs can be obtained from the received SCI. The TX-RX distance can be calculated based on the location information of another terminal and the location information of the terminal itself.

[0212] **Sidelink reference signal received power (SL RSRP) can be measured from the SCI received in sensing window A.

[0213] **The side link received signal strength indicator (SL RSSI) can be measured in sensing window A.

[0214] The sensing window A may be mainly used to determine resources for UE autonomous resource allocation (mode 2) by sensing periodic services. If it is determined using a side link measurement result such as SL RSRP or SL RSSI that it is invalid to identify periodic resource allocation information of another terminal through SCI decoding and to allocate transmission resources to resources used by another terminal, the corresponding resources may be excluded from the resource selection window 1403. Fig.14A As shown, if the trigger for transmission resource selection occurs in time slot n (indicated by reference numeral 1401), the resource selection window 1403 may be defined as follows.

[0215] *The resource selection window may be defined as a time slot interval of [n+T1, n+T2]. Here, T1 and T2 may be determined as fixed values ​​or may be determined as configurable values. Alternatively, T1 and T2 may be determined to be within a fixed range, and the UE may configure appropriate values ​​for them within the fixed range in consideration of implementation.

[0216] **As an example, where T1 and T2 are determined to be within a fixed range and the UE is configured with appropriate values ​​for them within the fixed range taking into account the implementation, these values ​​may be configured for UE implementation within the range of T1≤4 and 20≤T2≤100.

[0217] * By using the sensing result performed in the sensing window A, the final transmission resource 1405 may be selected in the resource selection window.

[0218] If sensing is performed using only sensing window A, such as Fig.14A As shown, by performing transmission resource selection through detection, the following transmission resource selection method can be used.

[0219] *Transmission resource selection method-1

[0220] ** Operation 1: Based on the resource pool information, determine the number Mtotal of resource candidates to which resources can be allocated in the resource selection window 1403. The details of Operation 1 can be understood by referring to Embodiment 1.

[0221] ** Operation 2: By using the sensing result in the sensing window A 1402, exclude the resource candidates that are determined to be invalid, to be occupied and used by another terminal in the resource selection window 1403, and have X (≤Mtotal) allocatable resources remaining. The method for excluding resources can be used by performing SCI decoding and sidelink measurement on another terminal.

[0222] ** Operation 3: Report the resource candidate list X to the higher layer of the UE, and randomly select the final transmission resource from among the X candidates via the higher layer of the UE (indicated by reference numeral 1406).

[0223] like Fig. 14B As shown, in the case where a trigger for transmission resource selection occurs at time slot n (denoted by reference numeral 1401), a sensing window B 1404 may be defined as follows.

[0224] * Sensing window B may be defined as a time slot interval of [n+T1', n+T2']. Here, T1' and T2' may be determined as fixed values ​​or may be determined as configurable. Alternatively, T1' and T2' are determined to be within a fixed range, and the UE may configure appropriate values ​​within the fixed range in consideration of implementation. In addition, in the case where k indicates the time slot in which the resource is finally selected, sensing window B stops in time slot k, and at this time sensing window B becomes [n+T1', k].

[0225] **T1' and T2' may be configured to be the same values ​​as those of T1 and T2 in the resource selection window 1403, respectively, or may be configured to be different values.

[0226] **For example, if T1' is configured as 0, T1' indicates that sensing is performed from a triggering time slot n for transmission resource selection.

[0227] **Depending on the configured values ​​of T1' and T2', the sensing window B can be configured as one time slot or one or more time slots.

[0228] *In sensing window B, SCI decoding and sidelink measurements of other UEs can be performed.

[0229] **The details of the sensing operation in the sensing window B can be understood by referring to Embodiments 2 and 3.

[0230] Sensing window B may be used to determine resources for UE autonomous resource allocation by additional sensing of periodic and non-periodic traffic to sensing window A (mode 2). Sensing window B, which is configured after triggering time slot n for selecting transmission resources, can sense non-periodic traffic that cannot be predicted in sensing window A using sidelink measurements of time slots to which actual transmission resources can be allocated. Sensing through sensing window B may be understood as an operation of performing traffic sensing, which is sensed in each time slot regardless of whether the traffic is periodic or non-periodic. If such a sensing window B is used, the time slot n used to select the transmission resource may be used to sense the non-periodic traffic that cannot be predicted in sensing window A. Fig. 14B The sensing window B shown performs sensing and accordingly performs transmission resource selection, and the following transmission resource selection method may be used.

[0231] *Transmission resource selection method-2

[0232] ** Operation 1: Perform sensing in a corresponding time slot in sensing window B ( 1404 ) to determine whether a corresponding resource is in an idle state.

[0233] ***The allocation unit of resources in the frequency domain may be A (≥1) subchannels or may be defined as all subchannels. The number Ntotal of resource candidates to which resources can be allocated in a corresponding time slot is determined according to the resource allocation unit in the frequency domain.

[0234] ***Sensing can be performed through SCI decoding and sidelink measurement.

[0235] ** Operation 2-1: If it is determined through sensing in Operation 1 that the corresponding resource is in an idle state, a final transmission resource 1406 is determined from the number Ntotal of resource candidates to which resources can be allocated in the corresponding time slot.

[0236] **Operation 2-2: If it is determined through sensing in operation 1 that the corresponding resource is in a busy state, the following operation may be selected.

[0237] ***If the next time slot is also configured via sensing window B 1404, go to the next time slot and perform operation 1.

[0238] ***If the next time slot is not configured via sensing window B 1404, the following operations may be considered.

[0239] ****The final transmission resource 1406 is determined by using QoS information or energy detection results in the current time slot. QoS information includes priority, waiting time, reliability, short-range service (ProSe) packet priority (PPPP), short-range service packet reliability (PPPR), minimum communication range required for transmission service, and priority information according to data rate requirements. Priority can represent PPPP and PPPR, and can be a value selected from a range of values, and data that needs to be sent on the side link can include a priority value.

[0240] ****The transmission in the current time slot can be canceled and a rollback operation can be performed.

[0241] If through Fig.14A and 14B As defined, sensing window A and sensing window B can be classified based on the time point at which the trigger for transmission resource selection occurs. Specifically, the sensing interval configured for selecting transmission resources before triggering time slot n can be defined as sensing window A, and the sensing interval configured after triggering time slot n can be defined as sensing window B.

[0242] Fig. 14C is an example of a case where sensing window A and sensing window B are configured simultaneously. If a trigger for transmission resource selection occurs in time slot n (indicated by reference numeral 1401), sensing window A 1402 and sensing window B 1404 can be understood by referring to the above definition. Fig. 14C As shown, if sensing is performed using sensing window A and sensing window B, and selection of transmission resources is performed accordingly, the following transmission resource selection method may be used.

[0243] *Transmission resource selection method-3

[0244] ** Operation 1: Based on the resource pool information, determine the number Mtotal of resource candidates to which resources can be allocated in the resource selection window 1403 .

[0245] ** Operation 2: By using the sensing result in the sensing window A 1402, exclude the resource candidates that are determined to be invalid, to be occupied and used by another terminal in the resource selection window 1403, and have X (≤Mtotal) allocatable resources remaining. The method for excluding resources can be used by performing SCI decoding and sidelink measurement on another terminal.

[0246] **Operation 3: Report the resource candidate list X to the higher layer of the UE, and randomly select Y candidates down from the X candidates in the higher layer.

[0247] **Operation 4-1: If the sensing window B 1404 is included in the resource selection window 1403, the UE selects the final transmission resource 1406 based on the transmission resource selection method-2 among Y candidates determined in the higher layer by using the sensing result of the sensing window B 1404 in the physical layer.

[0248] *** The case where the sensing window B 1404 is included in the resource selection window 1403 corresponds to Fig. 14C The condition can be determined by the configuration of T1 and T2 as well as T1' and T2'.

[0249] ** Operation 4-2: In the case where the sensing window B is not included in the resource selection window 1403, the final transmission resource 1406 is selected using the sensing result in the sensing window B in the physical layer based on the transmission resource selection method-2.

[0250] *** The case where the sensing window B 1404 is not included in the resource selection window 1403 corresponds to Fig. 14C The condition can be determined by the configuration of T1 and T2 as well as T1' and T2'.

[0251] In the transmission resource selection method-3, the operation of selecting Y candidates from a higher layer (operation 3) may be omitted, and the following method may be used.

[0252] *Transmission resource selection method-4

[0253] ** Operation 1: Based on the resource pool information, determine the number Mtotal of resource candidates to which resources can be allocated in the resource selection window 1403 .

[0254] ** Operation 2: By using the sensing result in the sensing window A 1402, exclude the resource candidates that are determined to be invalid, to be occupied and used by another terminal in the resource selection window 1403, and have X (≤Mtotal) allocatable resources remaining. As a method for excluding resources, SCI decoding and sidelink measurement of another terminal may be performed.

[0255] ** Operation 3-1: If the sensing window B 1404 is included in the resource selection window 1403, the UE selects a final transmission resource 1406 among X candidates by using the sensing result of the sensing window B 1404 in the physical layer based on the transmission resource selection method-2.

[0256] *** The case where the sensing window B 1404 is included in the resource selection window 1403 corresponds to Fig. 14C The condition can be determined by the configuration of T1 and T2 as well as T1' and T2'.

[0257] ** Operation 3-2: In the case where the sensing window B is not included in the resource selection window 1403, the final transmission resource 1406 is selected using the sensing result in the sensing window B in the physical layer based on the transmission resource selection method-2.

[0258] *** The case where the sensing window B 1404 is not included in the resource selection window 1403 corresponds to Fig. 14C The condition can be determined by the configuration of T1 and T2 as well as T1' and T2'.

[0259] In the case where sensing window A and sensing window B are configured at the same time, the final resource selection can be determined by resource selection window 1403 and sensing window B 1404. The transmission resource selection method-3 or transmission resource selection method-4 proposed above configures sensing window A and sensing window B at the same time to perform sensing when periodic and non-periodic services coexist, and optimizes transmission resource selection accordingly.

[0260] The implementation of the sensing and transmission resource selection operations in the UE autonomous resource allocation (mode 2) of the above-mentioned side link can be performed in various methods. For example, in the case of configuring sensing window A and sensing window B at the same time, the UE can be implemented so that the UE always performs sensing of sensing window A, and if a trigger for transmission resource selection occurs in time slot n, the UE performs sensing of sensing window B, and selects the final transmission resource accordingly. However, since the UE always performs the sensing operation of sensing window A, the sensing result of sensing window A can be used at any time, so there may be an advantage in terms of waiting time in terms of the selection of transmission resources, but it may be disadvantageous in terms of UE energy consumption. Therefore, according to another method, the UE can be implemented so that in the case of a service that needs to be sent, the UE immediately performs sensing of sensing window A, and if a trigger for transmission resource selection occurs in time slot n, the UE performs sensing of sensing window B, and selects the final transmission resource accordingly. According to another method, there may be the following advantages: minimizing the energy consumption of the UE by performing sensing only as needed, but there may be disadvantages in terms of waiting time in terms of the selection of transmission resources.

[0261] In the above, an example of operations of finding empty frequency-time resources for device-to-device communication via a side link and sending signals in the found resources has been described, but the methods and apparatus provided in the present disclosure are not limited thereto and can be applied to various channel occupancy and channel reservation methods.

[0262] Fig.15A A "Mode 1" method is shown, which is a method for receiving scheduling information and performing sidelink data transmission, as described above. Fig.12 As shown. In the present disclosure, the method for receiving scheduling information from a base station and performing sidelink communication based on the scheduling information is referred to as "Mode 1", but may be referred to differently. UE 1501 for performing transmission via a sidelink receives scheduling information 1509 for sidelink communication from a base station 1511. In the present disclosure, UE 1501 for performing data transmission via a sidelink may be referred to as a transmitting terminal, and UE 1503 for performing data reception via a sidelink may be referred to as a receiving UE. However, each of the transmitting terminal 1501 and the receiving UE 1503 may perform data transmission or reception via a sidelink. Scheduling information 1509 for sidelink communication may be obtained by receiving downlink control information (DCI), and the DCI may include the following information.

[0263] - A carrier indicator, which may be used for the purpose of scheduling a side link for another carrier in a state where carrier aggregation (CA) has been applied;

[0264] - the lowest index when allocating subchannels for initial transmission, which can be used to allocate frequency resources at the time of initial transmission;

[0265] -Information to be included in the sidelink control information:

[0266] >For example, frequency resource allocation information may include resource allocation information or resource reservation information for initial transmission, retransmission, and N transmissions after transmission;

[0267] > Information about the time interval between initial transmission and retransmission;

[0268] - information about the sidelink time slot structure, wherein the information may include information about which time slots and symbols may be used for the sidelink;

[0269] -HARQ-ACK or / and CSI feedback timing information, wherein the information may include timing information for sending HARQ-ACK feedback or CSI feedback to the base station via the side link;

[0270] - Receiver ID: which is ID information about a terminal that is to perform reception; and

[0271] - QoS information, such as priority, which is information related to the priority with which data is to be transmitted.

[0272] Scheduling can be used for one-time transmission of the scheduling side link, or can be used for periodic transmission, semi-persistent scheduling (SPS), or a configured grant transmission method (configured grant). The scheduling method can be distinguished by an indicator included in the DCI, an RNTI scrambled to the CRC added to the DCI, or an ID value. 0 bits or the like can be added to the DCI to allow the size of the DCI to be the same as the size of another DCI format for DCI for downlink scheduling or uplink scheduling.

[0273] The transmitting terminal 1501 receives DCI for sidelink scheduling from the base station 1511, transmits a PSCCH including sidelink scheduling information 1507, and transmits a PSSCH, which is data corresponding to the information (indicated by reference numeral 1505). The sidelink scheduling information 1507 may be sidelink control information (SCI), and the SCI may include the following information:

[0274] -HARQ process number, which is a HARQ process ID used for HARQ-related operations for transmitting data;

[0275] - New Data Indicator (NDI), which is information about whether the data currently being sent is new data;

[0276] - Redundancy version, which is information about which parity bit is sent at the mapping time after channel coding of the data;

[0277] - A first layer source ID, which is the ID information in the physical layer of the terminal performing transmission;

[0278] - A first layer destination ID, which is ID information in the physical layer of the terminal performing reception;

[0279] - Frequency domain resource allocation for scheduling PSSCH, which is the frequency domain resource configuration information of the transmitted data;

[0280] -MCS, which is information about the modulation order and coding rate;

[0281] -QoS indication, which may include priority, target latency / delay, target distance, target error rate, etc.;

[0282] - Antenna port, which is information about the antenna port used for data transmission;

[0283] -DMRS sequence initialization, which may include information such as an ID value for initializing a DMRS sequence;

[0284] -PTRS-DMRS association, which may include information related to PTRS mapping;

[0285] - CBGTI, which can be used as an indicator for retransmissions through the CBG unit;

[0286] - Resource reservation, which is information for resource reservation;

[0287] -Time interval between initial transmission and retransmission, which is information about the time interval between initial transmission and retransmission;

[0288] - a retransmission index, which is an indicator identifying a retransmission;

[0289] - A transmission format / broadcast type indicator, which is an indicator that identifies the transmission format or distinguishes between unicast / multicast / broadcast;

[0290] - Area ID, which is the location information of the sending terminal;

[0291] -NACK distance, which is a reference indicator for determining whether the receiving terminal needs to send HARQ-ACK / NACK;

[0292] -HARQ feedback indication, which may include whether HARQ feedback needs to be sent, or whether HARQ feedback is being sent;

[0293] -Time domain resource allocation for scheduling PSSCH, which is the time domain resource information of the transmitted side link data;

[0294] - a second SCI indication, which is an indicator including mapping information of a second SCI in case of two-level control information; and

[0295] - DMRS pattern, which is information on a DMRS pattern (eg, positions of symbols through which the DMRS is mapped).

[0296] The control information may be transmitted to the receiving terminal after being included in a single piece of SCI, or may be transmitted after being included in two pieces of SCI. Transmission through two pieces of SCI may be referred to as a 2-level SCI method.

[0297] Fig. 15B An example of a "Mode 2" method is shown, which is a method for performing sidelink communication without receiving scheduling information from a base station. In the present disclosure, a method for performing sidelink communication by determining a transmitting terminal 1521 without receiving scheduling information from a base station is referred to as Mode 2, but may be referred to differently. The transmitting terminal 1521 sends a PSCCH including sidelink scheduling information 1527 to a receiving terminal 1523 (indicated by reference numeral 1527), and sends a PSSCH corresponding to the information to a receiving terminal 1523 (indicated by reference numeral 1525). The sidelink scheduling information 1527 may include an SCI, and the SCI may include information that is the same as or similar to the SCI information of Mode 1.

[0298] In the present disclosure, a downlink (DL) may indicate a link through which a signal is transmitted from a base station to a terminal. In the present disclosure, an uplink (UL) may indicate a link through which a signal is transmitted from a terminal to a base station.

[0299] The present disclosure provides a method and apparatus for sending feedback, wherein the feedback includes HARQ-ACK feedback of a terminal that has received data through a side link, and a method and apparatus for receiving feedback, wherein the feedback includes HARQ-ACK feedback of a terminal that has sent data.

[0300] [First embodiment]

[0301] The first embodiment provides a method and apparatus for determining a reference time value with a minimum time difference for transmitting HARQ-ACK feedback.

[0302] Fig.16AAn example of a mapping structure of a physical channel mapped to a time slot via a side link is shown. Before sending the corresponding time slot 1601, the transmitting terminal may send a preamble signal 1602 via one or more symbols. If the receiving terminal amplifies the power of the received signal, the preamble signal may be used to allow the receiving terminal to correctly perform automatic gain control (AGC) so as to adjust the strength of the amplification. In addition, the transmission of the preamble signal may be determined based on whether the transmitting terminal sends the previous time slot of the corresponding time slot 1601. That is, if the corresponding transmitting terminal sends a signal to the same terminal in the previous time slot of the corresponding time slot 1601, the transmission of the preamble signal may be omitted. PSCCH 1603 including control information is transmitted via the initial symbol of time slot 1601, and PSSCH a-04 scheduled by the control information of PSCCH 1603 may be transmitted via the initial symbol of time slot 1601 or its subsequent symbols. Sidelink control information (SCI) as part of the control information may be mapped and transmitted to PSSCH (1604). In addition, Fig.16A An example is shown in which a physical sidelink feedback channel (PSFCH) 1605, which is a physical channel for sending feedback information, is located at the end of the time slot 1601. A certain idle time period is guaranteed between PSSCH a-04 and PSFCH 1605, so that a terminal that has sent or received PSSCH a-04 can prepare for the transmission or reception of PSFCH 1605. After sending or receiving PSFCH 1605, an empty interval can be guaranteed within a certain time period.

[0303] In one embodiment, the terminal may pre-receive the configuration of the position of the time slot to which the PSFCH is sent. The terminal's pre-receipt of the configuration may be predetermined in the process of creating the time slot, may be sent when connected to the side link related system, may be sent from the base station when connected to the base station, or may be received from another terminal.

[0304] Fig. 16B An example in which resources capable of transmitting or receiving PSFCH are configured for each time slot is shown. For example, if the period of resources capable of transmitting or receiving PSFCH can be configured by a parameter such as periodicity_PSFCH_resource, then Fig. 16B It may be the case that periodicity_PSFCH_resource corresponds to 1 time slot. Alternatively, the period may be configured in millisecond (msec) units, and the configuration of resources for transmission of PSFCH may be obtained in each time slot according to the subcarrier spacing (SCS). Fig. 16B In the example, feedback information of the PSSCH received through scheduling in time slot n can be sent through the PSFCH in time slot (n+1).

[0305] Fig. 16C An example is shown in which resources are configured to transmit or receive PSFCH every four slots. Fig. 16C An example with such a configuration is shown, so that PSFCH is transmitted or received only in the last time slot c-04 among four time slots c-01, c-02, c-03 and c-04. Similarly, Figure 16 shows an example in which PSFCH c-13 is configured to be transmitted or received only in the last time slot c-08 among four time slots c-05, c-06, c-07 and c-08. The index of the time slot can be a time slot determined in a resource pool. That is, the four time slots c-01, c-02, c-03 and c-04 are not physically continuous time slots, but time slots that appear continuously in the time slots belonging to the resource pool (or time slot pool) used by the transceiver. Fig. 16C The arrow in may indicate the time slot of the PSFCH to which the HARQ-ACK feedback information of the PSSCH is sent. For example, the HARQ-ACK information of the PSSCH sent (or scheduled) in time slots c-01, c-02, and c-03 is included in PSFCH c-11 and is sent or received, and PSFCH c-11 may be sent through time slot c-04. Similarly, the HARQ-ACK information of the PSSCH sent (or scheduled) in time slots c-04, c-05, c-06, and c-07 is included in PSFCH c-13 and is sent or received, and PSFCH c-13 may be sent through time slot c-08. The situation in which the HARQ-ACK feedback information of the PSSCH sent in time slot c-04 is not sent through the same time slot c-04 may occur because the terminal may not have enough time to complete the decoding of the PSSCH sent through time slot c-04 and transmit the PSFCH in the same time slot c-04. That is, this may happen because the minimum processing time required to process the PSSCH and prepare the PSFCH is not small enough.

[0306] When the terminal sends or receives PSFCH, it is necessary to know the number of HARQ-ACK feedback bits included in PSFCH so that transmission or reception can be performed correctly. The number of HARQ-ACK feedback bits included in PSFCH and whether to include PSSCH HARQ-ACK bits can be determined based on a combination of at least one of the following parameters.

[0307] - The periodicity of the time slots in which PSFCH transmission and reception are enabled by parameters such as periodicity_PSFCH_resource

[0308] -Whether to perform HARQ-ACK bundling. The HARQ-ACK bit of the PSFCH transmitted in a predetermined number of time slots before PSFCH transmission or reception may be a value determined by an AND operation. (In other words, if 1 is a NACK bit, the HARQ-ACK bit is determined as NACK).

[0309] -The number of transport blocks (TBs) included in the PSSCH

[0310] -Whether to use and configure code block group (CBG) unit retransmission

[0311] - Whether HARQ-ACK feedback is activated

[0312] -The number of PSSCHs actually transmitted or received

[0313] - Minimum processing time of the terminal required to prepare for PSSCH processing and PSFCH transmission (K)

[0314] In the case of receiving PSSCH in time slot n, and in the case of configuring or giving resources capable of transmitting PSFCH in time slot (n+x), the terminal receiving PSSCH uses the smallest x among integers greater than or equal to K, maps the HARQ-ACK feedback information of PSSCH to the PSFCH of time slot (n+x) and transmits PSSCH. K may be a value preconfigured by the transmitting terminal, or a value configured in the resource pool in which the corresponding PSSCH or PSFCH is transmitted, and each terminal may exchange its capabilities with the transmitting terminal in advance for configuration.

[0315] In the above, K is a parameter indicating the interval between the transmission time slots of the PSSCH and HARQ-ACK received by the terminal, and may be a value determined or configured according to the processing time capability of the terminal (i.e., the ability to quickly process the PSSCH). According to an example, a terminal capable of normal processing (which may be referred to as capability type 1 in the present disclosure) may have a K value determined as 2 in the equation, and a terminal capable of fast processing (which may be referred to as capability type 2 in the present disclosure) may have a K value determined as 1 in the equation. For example, a K value may be provided as shown in Table 5 below. Information about the processing capability of the terminal may be exchanged between terminals using PC5-RRC. K may be a value determined according to at least one of a subcarrier spacing (SCS), UE capability, a configuration value with a transmitting terminal, or a resource pool configuration, as provided in below.

[0316] [Table 5]

[0317] SCS K for processing capability type 1 K for processing capability type 2 15kHz 2 1 30kHz 2 1 60kHz 3 2 120kHz 3 2

[0318] According to the above method, for example, when N=2 and K is 1, that is, when PSFCH transmission resources are configured for every N time slots in the resource pool, and when PSSCH is sent and HARQ-ACK of PSSCH can be sent from at least K subsequent time slots (K=1) (that is, the time slot immediately thereafter), the time slot for sending HARQ-ACK feedback can be determined as follows. Fig.17 As shown. Fig.17 The logical time slot index in the resource pool corresponding to the first column represents the index of the time slot configured as the resource pool. That is, the logical time slot index is only allocated to the time slot configured as the resource pool among the multiple time slots, and the logical time slot index is not allocated to the time slot that is not configured as the resource pool. Fig.17 In the second column of the table, time slot may indicate the index of a physical time slot. Fig.17 In the second column field, it can be identified that the time slot index is allocated according to the order of the physical time slot, regardless of whether the time slot is configured as a resource pool. Fig.17 The third column of is a field indicating whether a time slot corresponds to a resource pool, and "0" may indicate that the corresponding time slot corresponds to a resource pool, while "X" may indicate that the corresponding time slot does not correspond to a resource pool. Fig.17 The fourth column is a field indicating whether PSFCH transmission is available. "0" indicates a time slot in which PSFCH transmission is available, and "X" indicates a time slot in which PSFCH transmission is not available. The time slot in which PSFCH transmission is available needs to correspond to the resource pool and can be determined according to the N value. Fig.17 The embodiment corresponds to an example in which N is 2. Therefore, the PSFCH may be transmitted at every second index interval in the index of the logical slot index in the resource pool. Fig.17 The fifth column of indicates the time slot to which the PSSCH corresponding to the HARQ-ACK feedback included in the PSFCH has been transmitted. For example, the PSFCH transmitted through time slot n may include the HARQ feedback information of the PSSCH scheduled in time slot (n-1) and time slot (n-2). Fig.17 When analyzing a table, each field of the table can be interpreted in the same way in the corresponding figure and table.

[0319] That is, according to Fig.17, the number of HARQ-ACK feedback bits that the terminal needs to send can be 2 bits in all PSFCHs. For example, if the receiving terminal does not receive PSSCH in time slot n and time slot (n+2), or does not receive PSCCH for scheduling PSSCH, there is no need to send PSFCH including HARQ-ACK feedback information through time slot (n+3). In addition, if PSSCH is received in time slot (n+3) and PSSCH is not received in time slot (n+4), or PSCCH for scheduling PSSCH is not received in time slot (n+4), the receiving terminal can send 1 bit of HARQ-ACK information of time slot (n+3) in time slot (n+8). Alternatively, if PSSCH is received in time slot (n+3), PSSCH is not received in time slot (n+4), or PSCCH for scheduling PSSCH is not received, the receiving terminal may send HARQ-ACK information of time slot (n+3) and HARQ-ACK information of time slot (n+4) in time slot (n+8). In this case, since the receiving terminal does not receive PSSCH in time slot (n+4), the HARQ-ACK feedback of time slot (n+4) may be configured as NACK and sent.

[0320] That is, if the receiving terminal transmits PSFCH in a specific time slot by considering the time slots included in the resource pool, the time slots in which the PSFCH resources are configured, the period N in which the PSFCH resources are configured, and K configured or determined according to the processing time of the terminal, the receiving terminal can determine the number of HARQ-ACK feedback bits to be included in the PSFCH. The determined number of HARQ-ACK feedback bits can be determined by the following equation.

[0321] [Equation 2]

[0322] The number n of HARQ-ACK bits to be included in the PSFCH transmitted through slot n=the number of slots included in the corresponding resource pool from slot (k-K+1) to slot (nK).

[0323] In <Equation 2>, time slot k may be a time slot including a PSFCH resource that is configured to be transmitted immediately before a PSFCH that may be transmitted via time slot n. Therefore, given N and K, the maximum number of HARQ-ACK feedback bits that a terminal needs to transmit via one PSFCH may be determined as Fig.18 shown.

[0324] That is to say, Fig.18In the example of , by considering from time slot (nK-N+1-K+1) to time slot (nK), as many HARQ-ACK feedback bits as the number of corresponding time slots can be sent to the PSFCH of time slot n. Obviously, in the case where the terminal does not receive the PSSCH through time slot (nK-N+1-K+1) to time slot (nK) or does not receive the PSCCH for scheduling the PSSCH, there is no need to send the PSFCH through time slot n. In the case where N and K are given above, the maximum number of HARQ-ACK feedback bits that the terminal needs to send through one PSFCH can be given by the following equation 3.

[0325] [Equation 3]

[0326] The maximum number of HARQ-ACK feedback bits that the terminal needs to send through one PSFCH = (N+K-1).

[0327] For example, when N=2 and K is 2, that is, when PSFCH transmission resources are configured for every N time slots in the resource pool, and when PSSCH is transmitted and HARQ-ACK for PSSCH can be transmitted from at least K subsequent time slots (K=2) (i.e., two time slots later), the time slot for transmitting HARQ-ACK feedback can be as follows: Fig.19 shown is determined.

[0328] That is, in Fig.19 In the time slot, the number of HARQ-ACK feedback bits to be sent by the terminal may be 1 bit, 2 bits, or 3 bits depending on the time slot. For example, the PSFCH including HARQ-ACK feedback information in time slot (n+2), time slot (n+3), and time slot (n+4) may be sent through time slot (n+8). If control information for scheduling at least one PSSCH in time slot (n+2), time slot (n+3), or time slot (n+4) is received, a PSFCH including 3 bits of HARQ-ACK feedback information is sent. The feedback information may be configured as NACK and sent in a time slot in which the PSSCH is not received.

[0329] Therefore, in the case where feedback transmission is performed via sidelink unicast or multicast communication, the number of feedback bits can be determined as (N+K-1), as given in <Equation 3>. That is, in this method, according to Fig.19 In the example shown, (N+K-1)=2+2-1=3, so it can be determined that 3 bits are always sent.

[0330] Alternatively, according to another example, in the case where feedback transmission is performed via sidelink unicast or multicast communication, the number of feedback bits may be determined as the maximum number of bits that need to be transmitted in all cases by considering the time slots, N, and K belonging to the resource pool. That is, in this method, according to Fig.19 In the example shown in , since the maximum number of bits that need to be transmitted in all cases is 3, the feedback transmission can be determined to always send 3 bits.

[0331] According to another example, in the case where feedback transmission is performed via sidelink unicast or group broadcast communication, the number of feedback bits can be used by calculating the number of time slots in which PSSCH can be transmitted, wherein PSSCH can be associated with HARQ-ACK feedback to be transmitted to PSFCH in the time slot to which PSFCH needs to be transmitted by considering N, k, and the time slots belonging to the resource pool, and the HARQ-ACK feedback will be transmitted to PSFCH in the time slot to which PSFCH needs to be transmitted. That is, in this method, according to Fig.19 In the example shown, it can be determined that 1 bit is sent through time slot n, 2 bits are sent through time slot (n+3), 3 bits are sent through time slot (n+8), 1 bit is sent through time slot (n+12), 2 bits are sent through time slot (n+14), and 2 bits are sent through time slot (n+16). Obviously, in the above example, if a control signal for scheduling PSSCH or PSSCH is not received in the time slot associated with the HARQ-ACK bit, where the control signal is determined to be sent by the terminal, it is considered that the transmitting terminal does not send any PSSCH during the time when the control signal for scheduling PSSCH or PSSCH is not received. Therefore, the transmission of PSFCH including HARQ-ACK may not be necessary.

[0332] According to another example, when N=2 and K is 3, that is, when PSFCH transmission resources are configured for every N time slots in the resource pool, and when PSSCH is transmitted and HARQ-ACK for PSSCH can be transmitted from at least K subsequent time slots (K=3) (that is, three time slots later), it can be as follows Fig. 20 The time slot for sending HARQ-ACK feedback is determined as shown.

[0333] That is, in Fig. 20In the time slot, the number of HARQ-ACK feedback bits that need to be sent by the terminal can be 0 bits, 1 bits, 2 bits, 3 bits, or 4 bits, depending on the time slot. For example, a PSFCH including HARQ-ACK feedback information in time slots (n+2), time slots (n+3), time slots (n+4), and time slots (n+5) can be sent through time slots (n+8). If control information for scheduling at least one PSSCH in time slots (n+2), time slots (n+3), time slots (n+4), and time slots (n+5) is received, a PSFCH including 4 bits of HARQ-ACK feedback information is sent. In the time slots in which the PSSCH is not received, the feedback information can be configured as NACK and sent.

[0334] According to another example, when N=4 and K is 3, that is, when PSFCH transmission resources are configured for every N time slots in the resource pool, and when PSSCH is transmitted and HARQ-ACK for PSSCH can be transmitted from at least K subsequent time slots (K=3) (that is, three time slots later), it can be as follows Fig.21 The time slot for sending HARQ-ACK feedback is determined as shown.

[0335] That is, in Fig.21 In the example, the number of HARQ-ACK feedback bits that need to be sent by the terminal may be 2 bits, 3 bits, 4 bits, 5 bits, or 6 bits depending on the time slot. For example, the PSFCH including HARQ-ACK feedback information in time slot (n+1), time slot (n+2), time slot (n+3), time slot (n+4), time slot (n+5), and time slot (n+6) may be sent through time slot (n+12). If control information for scheduling at least one PSSCH in time slot (n+1), time slot (n+2), time slot (n+3), time slot (n+4), time slot (n+5), and time slot (n+6) is received, a PSFCH including 6 bits of HARQ-ACK feedback information is sent. In a time slot in which the PSSCH is not received, the feedback information may be configured as NACK and sent.

[0336] like Fig.21 As shown, according to N and K, the number of HARQ-ACK feedback bits that the terminal needs to send can be increased to N bits or more. In this case, information corresponding to a large number of bits needs to be sent in the PSFCH, so this may cause disadvantages by increasing the probability of decoding errors in the PSFCH. Therefore, the terminal can send only the last K bits of feedback that need to be sent, and the remaining bits may not be sent. In the above, K can be the same as N, and N is the PSFCH resource configuration period, but is not limited to this.

[0337] According to another example, when N=2 and K is 3, that is, when PSFCH transmission resources are configured for every N time slots in the resource pool, and when PSSCH is transmitted and HARQ-ACK for PSSCH can be transmitted from at least K subsequent time slots (K=3) (that is, three time slots later), it can be as follows Fig. 22 The time slot for sending HARQ-ACK feedback is determined as shown.

[0338] That is, in Fig. 22 In the example, the number of HARQ-ACK feedback bits that need to be sent by the terminal can be 0 bits, 1 bit, 2 bits, 3 bits, or 4 bits, depending on the time slot. For example, time slot (n+12) may not include a side link time slot in which the corresponding PSSCH is sent, where the HARQ-ACK feedback will be sent over the PSSCH. That is, there may be a situation where, depending on N, k, and the resource pool configuration, there are no feedback bits to be sent in the PSFCH resources of a particular time slot, and the minimum number of bits for sending HARQ-ACK feedback can be given by the following <Equation 4>.

[0339] [Equation 4]

[0340] The minimum number of HARQ-ACK feedback bits that the terminal needs to send through one PSFCH = max(N-K+1, 0).

[0341] In the above, max(a, b) can represent the larger value between a and b. That is, in Fig. 22 In the example provided in , since the HARQ-ACK to be sent does not always exist in the time slot (n+12), the UE can assume that there is no PSFCH resource in the corresponding time slot. That is, although the PSFCH resource is configured to exist, the PSFCH resource can be ignored and PSSCH transmission or reception can be performed.

[0342] In the present disclosure including the current embodiment, N may be configured in a value including at least one of 1, 2, and 4 as an example. However, N is not limited thereto. In addition, the above configuration may be different for each resource pool.

[0343] In the disclosure including the current embodiment, with reference to HARQ-ACK, the corresponding PSSCH or PSSCH may be a PSSCH for unicast or multicast, sent from the same terminal, and configured or indicated to send HARQ-ACK. That is, a PSSCH that does not need to send HARQ-ACK may not need to apply the proposed technology. In addition, in the disclosure including the current embodiment, a PSCCH for scheduling a PSSCH may be control information for scheduling a PSSCH, and the control information may not need to be sent via the PSCCH. In addition, the control information may be one piece of control information, but multiple pieces of control information may schedule one PSSCH.

[0344] In the above description, the K value used as a reference for a time point at which feedback transmission is performed may be determined by the following method.

[0345] Method 1: k is fixed to 2 regardless of the size of the subcarrier. This is because, considering the processing time capability of the terminal, the minimum processing time exceeding 28 symbols may not be defined in all subcarrier intervals. In the present disclosure, a method for fixing K=2 is provided, but K is not limited to 2 and can be changed and applied to other values.

[0346] Method 2: Determine the value of K based on the size of the subcarrier being used. For example, for 15kHz and 30kHz, k=2, and for 60kHz and 120kHz, k=3.

[0347] Method 3: This method configures or preconfigures the K value according to the resource pool, or configures the method according to unicast or multicast communication performed in the resource pool.

[0348] Method 4: A method determined by a combination of at least one of the following, such as the processing capability of the terminal and the time interval between PSSCH and PSFCH:

[0349] >The time point when PSSCH transmission ends, that is, the last symbol time

[0350] >The time point when PSFCH transmission starts, that is, the first symbol time

[0351] >The processing power of the terminal (which can be associated with the baseband processing power)

[0352] >Time slot boundary point

[0353] The above description can be modified and applied as follows. When PSSCH is received in time slot n, the terminal receiving PSSCH sends HARQ-ACK feedback information of PSSCH through the earliest PSFCH in PSFCH, where the interval between PSSCH and PSFCH is greater than or equal to y symbols. In the above, y can be a preconfigured value from the transmitting terminal or a value configured in the resource pool in which the corresponding PSSCH or PSFCH is transmitted, and for the configuration of y, each terminal can exchange terminal capabilities with the transmitting terminal in advance, and y can be determined based on the subcarrier spacing.

[0354] [Second embodiment]

[0355] The second embodiment provides a method and apparatus for determining a PSFCH to be transmitted. Fig.23 An example of configuring a physical time slot index and a logical time slot index of a time slot included in a resource pool according to a resource pool configuration in a physical time slot is shown. Fig.23 In the first table, in the case where PSFCH is transmitted every 4 time slots according to the physical time slot number, the corresponding time slot is not included in the resource pool, so PSFCH cannot be transmitted in the corresponding time slot. Fig.23 The second table, the third column indicates where the PSFCH can be sent if N=4 is configured based on a logical time slot belonging to a resource pool. The fourth column indicates where the PSFCH can be sent if N=4 is configured based on a physical time slot. Even if the N value is configured based on a physical time slot, if the time slot does not belong to a resource pool, the time slot can be used to send the PSFCH in a time slot belonging to a resource pool of the next cycle.

[0356] Fig.24 A method of transmitting feedback information by including the feedback information in the PSFCH is shown according to whether the physical time slot is included in the resource pool and the position of the time slot configured by the PSFCH resource. Fig.24 An example of N=4 and K=2 is shown. That is, Fig.24 It is shown that the PSFCH resource is configured for every 4 time slots in the resource pool, and feedback can be sent from two time slots after receiving the data according to the processing capability of the terminal. For example, the HARQ-ACK feedback of the data (PSSCH) sent through time slot (n-1), time slot n, time slot (n+2), time slot (n+3) and time slot (n+4) can be sent through time slot (n+8). However, if the PSFCH that can be sent by the terminal is capable of sending 1 bit or 2 bits for each PSFCH, and if the terminal receives the PSSCH through all 5 time slots, the terminal can determine the PSFCH to be sent by applying one of the following methods.

[0357] Method 1: A method for dividing and allocating 1 bit or 2 bits to a PSFCH and transmitting a plurality of PSFCHs.

[0358] Method 2: A method for transmitting only the HARQ-ACK by including the HARQ-ACK previously transmitted via PSSCH in one PSFCH.

[0359] Method 3: A method for sequentially transmitting 1 bit or 2 bits for a PSSCH with high QoS.

[0360] Method 4: A method for dividing and allocating 1 bit or 2 bits to a PSFCH and transmitting only one PSFCH.

[0361] Fig.24 "Method 1" is shown in more detail above. For example, it is determined that the HARQ-ACK feedback information of the PSSCH transmitted through time slots (n-1) and n is transmitted through one PSFCH 2401, the HARQ-ACK feedback information of the PSSCH transmitted through time slots (n+2) and (n+3) is transmitted through another PSFCH 2403, and the HARQ-ACK feedback information of the PSSCH transmitted through time slot (n+4) is transmitted through another PSFCH 2405. According to one embodiment, only one bit may be transmitted through the last PSFCH.

[0362] In this case, depending on whether a PSSCH is received or whether information related to a PSCCH for scheduling a PSSCH is received, the terminal may need to send one or more PSFCHs. In the case of sending multiple PSFCHs, the terminal can determine the PSFCH to be sent by applying one or more of the following methods. For example, in the case where multiple PSSCHs are sent at the same time point or through the same time slot, the following method can be applied.

[0363] Method a-1: By allocating the transmission power of PSFCH until the maximum available power of the terminal is reached, multiple PSFCHs are transmitted simultaneously in the first allocated power sequence, wherein in the first allocated power sequence, the feedback of the first PSSCH received is transmitted to the PSFCH, and in the time slot sequence, the PSSCH corresponding to the HARQ-ACK feedback included in the PSFCH is transmitted, and then the power of the PSFCH is allocated. If the PSCCH or PSSCH corresponding to the feedback included in the PSFCH is not transmitted, the corresponding PSFCH is not transmitted. That is, the power of the PSFCH can be assumed to be 0.

[0364] Method a-2: First, determine the power of one or more PSFCHs to be transmitted, and if the PSFCH transmission power is greater than the maximum available power Pc,max of the terminal, reduce the PSFCH transmission power so that the total number of PSFCH powers to be transmitted becomes Pc,max corresponding to the ratio of the predetermined PSFCH power. Alternatively, the terminal may adjust the transmission power of a certain PSFCH, and may not adjust the determined transmission power of a certain PSFCH according to a predetermined priority. In addition, in the case of a PSFCH for unicast transmission, the terminal may not adjust the transmission power, and in the case of a PSFCH for multicast transmission, the terminal may adjust the transmission power.

[0365] Method a-3: When multiple PSFCHs need to be transmitted, a PSFCH including HARQ-ACK feedback information having the maximum number of bits is transmitted. If there are multiple PSFCHs including HARQ-ACK feedback information having the maximum number of bits, the terminal may randomly select a PSFCH to be arbitrarily transmitted.

[0366] Method a-4: When multiple PSFCHs need to be sent, the PSFCH including feedback of unicast data may be prioritized over the PSFCH including feedback of multicast data. That is, the PSFCH including feedback of multicast data is not sent, but the PSFCH including feedback of unicast data may be sent.

[0367] Method a-5: In the case where multiple PSFCHs need to be sent, the PSFCH to be sent can be determined based on the priority or QoS value corresponding to the PSSCH corresponding to the HARQ-ACK feedback included in the PSFCH. If multiple PSSCHs are mapped to one PSFCH, the value with the highest priority in the priority or QoS of the PSSCH can be applied.

[0368] According to the above-mentioned method a-1, method a-2 and method a-3, the method may be applied after determining that HARQ-ACK feedback for unicast data transmission takes precedence over HARQ-ACK feedback for multicast data transmission.

[0369] In addition, in the case where multiple PSFCHs are sent according to the above-mentioned methods a-1, a-2 and a-3, feedback corresponding to a PSSCH having a QoS value or priority value lower than a preconfigured QoS threshold may not be sent.

[0370] [Example (2-1)]

[0371] Embodiment (2-1) provides a method and apparatus for sending feedback by a terminal when the second embodiment is applied, wherein HARQ-ACK feedback for PSSCH sent from different terminals needs to be sent through the same time slot or with the same timing.

[0372] In the above, Fig.24 "Method 1" is described in more detail. For example, HARQ-ACK for PSSCH transmitted through time slot (n-1), time slot n, time slot (n+2), time slot (n+3), and time slot (n+4) may be mapped to separate PSCFHs and transmitted. In this case, the terminal may need to transmit up to 5 PSFCHs simultaneously. At this time, feedback may be transmitted using "Method a-1" to "Method a-5" provided in the second embodiment.

[0373] The above-mentioned method a-1, method a-2 and method a-3 may be applied after determining that HARQ-ACK feedback for unicast data transmission takes precedence over HARQ-ACK feedback for multicast data transmission.

[0374] In addition, in the case where multiple PSFCHs are sent according to the above-mentioned methods a-1, a-2 and a-3, feedback corresponding to a PSSCH having a QoS value or a priority value lower than a preconfigured QoS threshold may not be sent.

[0375] That is, for example, if there are three PSFCHs that the terminal needs to send before applying the method of allocating or reducing the power of three PSFCHs according to the ratio, the power of the PSFCH including feedback corresponding to the PSSCH having a QoS value or priority value lower than the configured or pre-configured QoS threshold may be determined to be 0. That is, the PSFCH may not be transmitted.

[0376] [Third embodiment]

[0377] The third embodiment provides a method and apparatus for determining the minimum unit of frequency resource allocation for PSSCH based on N, where N is the time slot period in the resource pool in which the resources for PSFCH are configured. Figures 25A to 25C In the figure, the horizontal direction represents the time domain and the vertical direction represents the frequency domain.

[0378] Fig.25A An example is shown for the case where N = 1. That is, feedback information of only one PSSCH may be included in one PSFCH and may be transmitted.

[0379] Fig.25BAn example of the case where N=2 is shown. As described in the (2-1) embodiment, if only one PSFCH includes feedback information for one PSSCH, then Fig.25B The maximum number of PSFCHs transmitted in one time slot can be greater than Fig.25A In this case, the probability of PSFCH collision between different terminals may increase.

[0380] Fig.25C An example of the case where N=2 is shown. Fig.25B In this case, since the maximum number of PSSCHs that can be transmitted in the system band may be reduced, the maximum number of PSSCHs to be transmitted through one time slot is less than Fig.25B The maximum number of PSSCHs in a Fig.25A In this case, the probability of PSFCH collision between different terminals can be compared Fig.25B situation has decreased.

[0381] For example, in the case of N=1, the allocation unit of PSSCH may be referred to as a subchannel. In the above, a subchannel may be a set or bundle of one or more consecutive PRBs. The size of a subchannel or the number of subchannels in a resource pool may be configured by a base station or may be preconfigured.

[0382] [Fourth embodiment]

[0383] The fourth embodiment provides a method and apparatus for exchanging, by a terminal, a capability of sending or receiving a feedback channel with another terminal or a base station through a side link, and performing communication with another terminal through the side link based on the capability.

[0384] In the side link signal transmission or reception, the terminal can share with another terminal or base station whether the type of PSFCH format transmitted or received by the terminal itself is supportable (UE capability). As another piece of information, information related to the number of PSFCHs that can be simultaneously transmitted or received by the terminal itself can be shared with another terminal or base station.

[0385] In the case of sending a signal to another terminal and receiving a signal from another terminal through a side link, the side link can be used to send or receive a signal through one of unicast, multicast and broadcast methods. In the case where the terminal performs unicast or multicast with another terminal, the UE capability exchange with the other terminal can be performed through PC5-RRC signaling. In addition, the process for exchanging UE capabilities can be a method in which one terminal requests (inquires) to transmit the UE capabilities from another terminal, or one terminal first transfers its UE capabilities to another terminal.

[0386] [Fifth embodiment]

[0387] The fifth embodiment provides a method for sending feedback when carrier aggregation (CA) on the sidelink can be used to simultaneously send or receive through multiple sidelink carriers. Various types of scenarios can be supported in the following various methods.

[0388] Method 1: In the case where a terminal can perform sidelink transmission via multiple sidelink carriers, data can be sent to one or more terminals via multiple carriers, and HARQ-ACK feedback for the sent data can be delivered from one or more receiving terminals. The received HARQ-ACK feedback can be sent to the base station together or preferentially.

[0389] Method 2: The sidelink can be used for one terminal to communicate with one terminal through multiple sidelink carriers. For example, UE 1 performs unicast communication with UE 2, and can perform data transmission or reception while performing sidelink CA through two sidelink carriers. In method 2, HARQ-ACK for data sent through two sidelink carriers can be fed back to the terminal that has sent data through one sidelink carrier. That is, even if data is sent to multiple sidelink carriers, HARQ-ACK feedback is sent through one carrier. The selection of the sidelink carrier for sending HARQ-ACK feedback can be determined by one or more combinations of the following methods.

[0390] Method a1: HARQ-ACK feedback is transmitted through a sidelink carrier in which a resource pool configured with PSFCH resources exists.

[0391] Method a2: HARQ-ACK feedback is sent through the sidelink carrier where the PSFCH resource appears first.

[0392] Method a3: HARQ-ACK feedback is sent through a sidelink carrier with a low index.

[0393] Method a4: Determine HARQ-ACK feedback based on the processing time of the terminal for processing the PSSCH.

[0394] The above methods a1 to a4 can be applied to the case where the terminal can send or receive in multiple resource pools through one carrier. For example, when data is sent to one receiving terminal or multiple receiving terminals in two resource pools and the HARQ-ACK feedback of the data is sent simultaneously, it can be considered that the feedback is not sent from each of the two resource pools but from one resource pool. That is, in the case of sending data from multiple resource pools, the HARQ-ACK feedback of the data can be sent from a specific resource pool.

[0395] [Sixth embodiment]

[0396] The sixth embodiment provides a method for indicating whether there is data other than HARQ process ID configuration and CSI when channel state information (which is channel measurement information through a side link) is sent from one terminal to another terminal by using a MAC control element (MAC CE).

[0397] Fig.26 An example of a slot structure in the case of transmitting a CSI-RS and an example of a slot structure in the case of reporting CSI information are shown.

[0398] If CSI-RS2603 is transmitted, the transmitting terminal 2611 transmits SCI 2601 and PSSCH 2602 together with CSI-RS2603. SCI 2601 may be mapped to PSCCH and transmitted. SCI 2601 may include a QoS value corresponding to PSSCH 2602. The receiving terminal 2613 measures the transmitted CSI-RS2603 for the side link to identify the channel state, generates CSI information for the side link, and transmits the CSI information to the transmitting terminal 2611. In the case of reporting CSI information, the CSI information is mapped to PSSCH 2605 and transmitted, and SCI 2604 is also transmitted in order to schedule PSSCH 2605. SCI 2604 may be mapped to PSCCH and transmitted. SCI 2604 may include a QoS value, and the value may be the same as the QoS value included in SCI 2601 used when transmitting CSI-RS2603. If CSI information as channel state information is included in MAC CE and transmitted, and if only CSI is included in MAC CE and no other data is transmitted, the QoS value corresponding to MAC CE can be determined as the QoS value included in SCI when CSI-RS2603 for CSI measurement is transmitted. In the case where CSI feedback is mapped to MAC CE or PC5-RRC and transmitted to PSSCH, since CSI feedback corresponds to SL-SCH, CSI feedback can be regarded as normal data in the physical layer. In this case, LDPC code can be applied to CSI like normal data.

[0399] If CSI is sent to MAC CE, if there is no other data, the terminal for sending CSI can notify the terminal for receiving CSI that there is no other data in the SCI for scheduling CSI. This notification can be sent to SCI via a one-bit field. If so, the bit field can be considered in the following cases.

[0400] Case 1: Operation of searching for an empty channel (frequency-time resource) to transmit data (channel sensing). For example, if the PSSCH includes only SCI when the receiving terminal receives the PSSCH, the corresponding PSSCH and SCI information obtained by scheduling the PSSCH may be ignored or not considered during channel sensing.

[0401] Case 2: In the case of measuring the channel busy ratio (CBR), the channel busy ratio is information about whether other terminals occupy the channel or resource pool. For example, if the corresponding PSSCH only includes SCI when the receiving terminal receives PSSCH from another terminal, the corresponding PSSCH and SCI information obtained by scheduling PSSCH can be ignored or not considered when calculating the CBR.

[0402] Case 3: In the case of measuring the channel occupancy rate (CR), the channel occupancy rate (CR) is information about whether the terminal itself occupies the channel or resource pool. For example, if the corresponding PSSCH only includes SCI when the transmitting terminal itself sends PSSCH, the resources occupied by the PSSCH that only includes CSI can be ignored or not considered when calculating the CR.

[0403] For convenience of explanation, the first to sixth embodiments of the present disclosure are divided and described, but since each embodiment includes operations related to each other, a combination of at least two embodiments may be effective.

[0404] In order to implement the above embodiment, Fig. 27 and Fig.28 The transmitter, receiver and processor of the terminal and the base station are respectively shown in the figure. According to the first to sixth embodiments, in order to configure HARQ-ACK feedback information, determine whether to send HARQ-ACK feedback, and perform feedback transmission operations, a method for sending or receiving between a base station and a terminal or a method for sending or receiving between a sending terminal and a receiving terminal is shown. In order to perform the method, the receiver, processing unit and transmitter of the base station and the terminal need to operate according to the embodiment.

[0405] Specifically, Fig. 27 is a block diagram showing the internal structure of a terminal according to an embodiment. Fig. 27As shown, the terminal according to the present disclosure may include a terminal receiver 2700, a terminal transmitter 2704, and a terminal processor 2702. In one embodiment, the terminal receiver 2700 and the terminal transmitter 2704 may be collectively referred to as a transceiver. The transceiver may send a signal to a base station or receive a signal from a base station. The signal may include control information and data. To this end, the transceiver may include: an RF transmitter configured to up-convert and amplify the frequency of the transmitted signal; an RF receiver configured to perform low noise amplification on the received signal, and down-convert the frequency of the signal, etc. The transceiver may receive a signal through a wireless channel, then output the received signal to the terminal processor 2702, and transmit the signal output from the terminal processor 2702 through the wireless channel. The terminal processor 2702 may control a series of processes to allow the terminal to be operated according to the aforementioned embodiments. For example, the terminal receiver 2700 receives control information from the base station, and the terminal processor 2702 determines whether to send HARQ-ACK feedback and feedback information based on the control information and the pre-configured configuration information, and may prepare to send accordingly. Thereafter, the terminal processor 2702 may send feedback scheduled in the terminal transmitter 2704 to the base station.

[0406] In the above-mentioned embodiment, SCI transmission is described under the assumption of a single-stage SCI method (or a first-level SCI). That is, the single-stage SCI method is a method in which a receiving terminal decodes an SCI for scheduling a PSSCH in order to decode the PSSCH. However, a two-stage SCI method may also be considered in order to perform side link operation. That is, the two-stage SCI method is a method as described below: wherein, in order for the receiving terminal to decode the PSSCH, two SCIs related to the scheduling need to be decoded so that the scheduling information can be identified. The two-stage SCI method may be applied to reduce overhead or reduce the number of blind decodings. According to an embodiment, the present application has been described under the assumption of a single-stage SCI method, that is, for example, a method for sending SCI via PSCCH has been described. However, in the two-stage SCI method, the first SCI is sent via PSCCH and the second SCI is sent via PSSCH, so that the receiving terminal can decode the PSSCH. It can be considered that in the two-stage SCI method, the first SCI and the second SCI are respectively sent via separate PSCCHs.

[0407] Fig.28 is a diagram showing the internal structure of a base station according to an embodiment. Fig.28As shown, a base station according to the present disclosure may include a base station receiver 2801, a base station transmitter 2805, and a base station processor 2803. In one embodiment, the base station receiver 2801 and the base station transmitter 2805 may be collectively referred to as a transceiver. The transceiver may send a signal to a terminal or receive a signal from a terminal. The signal may include control information and data. In order to transmit or receive a signal, the transceiver may include: an RF transmitter configured to up-convert and amplify the frequency of the transmitted signal; an RF receiver configured to perform low noise amplification on the received signal and down-convert the frequency of the signal, etc. The transceiver may receive a signal through a wireless channel, then output the received signal to the base station processor 2803, and send the signal output from the base station processor 2803 through a wireless channel. The base station processor 2803 may control a series of processes to allow the base station to be operated according to the aforementioned embodiments. For example, the base station processor 2803 may configure control information according to the HARQ-ACK feedback information of the terminal required by the base station, and control to receive feedback according to the control information. Thereafter, the base station transmitter 2805 transmits relevant scheduling control information, and the base station receiver 2801 receives the feedback information and the scheduling information.

[0408] On the other hand, the embodiments of the present disclosure disclosed in this specification and the accompanying drawings are only to provide specific examples in order to easily explain the technical content of the present disclosure and help understand the present disclosure, rather than to limit the scope of the present disclosure. That is to say, it is obvious to those skilled in the art that other modifications based on the technical ideas of the present disclosure can be implemented. In addition, each of the above-mentioned embodiments can be operated in combination with each other as needed. In addition, based on the technical ideas of the above-mentioned embodiments, the above-mentioned embodiments can be implemented in other modifications of LTE systems, 5G systems, etc.

[0409] Although the present disclosure has been described with various embodiments, various changes and modifications may be suggested to one skilled in the art. The present disclosure is intended to encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A method for providing feedback of a hybrid automatic repeat request (HARQ) in a communication system, performed by a terminal, the method comprising: generating HARQ feedback information for data scheduled by the terminal in at least one time slot; Determining the transmission timing of the HARQ feedback information based on a minimum processing time of a physical sidelink feedback channel PSFCH transmission of the terminal; as well as Sending the HARQ feedback information based on the determined timing; The minimum processing time of the PSFCH transmission is determined based on at least one of a subcarrier spacing, a configuration of a resource pool, or a time interval between a physical sidelink shared channel PSSCH and the PSFCH, The maximum number of bits of the HARQ feedback information is determined based on N and K. Wherein, N corresponds to the period in which PSFCH resources are configured, and K corresponds to the minimum processing time of the PSFCH transmission. 2 . The method according to claim 1 , wherein the minimum processing time of the PSFCH transmission is determined based on whether the configuration of the resource pool is a configuration of unicast transmission or a configuration of multicast transmission.

3. The method of claim 1, wherein the minimum processing time for the PSFCH transmission is determined based on a last symbol of the PSSCH and a first symbol of the PSFCH.

4. The method according to claim 1, wherein sending the HARQ feedback information comprises: In the case where a plurality of PSFCHs are to be transmitted, a PSFCH to be transmitted among the plurality of PSFCHs is determined based on a PSSCH sequence corresponding to the plurality of PSFCHs or a quality of service QoS of the PSSCH.

5. The method according to claim 1, wherein sending the HARQ feedback information comprises: In case a plurality of PSFCHs are to be transmitted, determining the transmit power of the PSFCHs, and When the sum of the transmit powers of the PSFCHs exceeds the maximum available power of the terminal, the transmit powers of the PSFCHs are adjusted according to a preconfigured ratio.

6. The method according to claim 1, wherein sending the HARQ feedback information comprises: In case that a plurality of PSFCHs are to be transmitted, the PSFCH to be transmitted is determined based on at least one of a plurality of HARQ feedback bits of each PSFCH or based on information related to whether the PSFCH is a feedback transmission of a multicast transmission. 7 . The method according to claim 1 , wherein the maximum number of bits of the HARQ feedback information is determined to be N+K-1.

8. The method according to claim 1, wherein the minimum number of bits of the HARQ feedback information is determined to be a larger value between N-K+1 and 0, in, In the case where multiple PSFCHs are transmitted for PSSCHs transmitted from different terminals, the PSFCH corresponding to unicast transmission takes precedence over the PSFCH corresponding to multicast transmission. The frequency band of the PSFCH is configured to be larger than the frequency band of the PSSCH.

9. A terminal for providing feedback of a hybrid automatic repeat request (HARQ) in a communication system, the terminal comprising: Transceiver; as well as A controller configured to: generating HARQ feedback information for data scheduled by the terminal in at least one time slot; Determining the transmission timing of the HARQ feedback information based on a minimum processing time of a physical sidelink feedback channel PSFCH transmission of the terminal; as well as sending, via the transceiver, HARQ feedback information based on the determined transmission timing, The minimum processing time of the PSFCH transmission is determined based on at least one of a subcarrier spacing, a configuration of a resource pool, or a time interval between a physical sidelink shared channel PSSCH and a PSFCH, The maximum number of bits of the HARQ feedback information is determined based on N and K. Wherein, N corresponds to the period in which PSFCH resources are configured, and K corresponds to the minimum processing time of the PSFCH transmission. 10 . The terminal according to claim 9 , wherein the minimum processing time of the PSFCH transmission is determined based on whether the configuration of the resource pool is a configuration of unicast transmission or a configuration of multicast transmission.

11. The terminal according to claim 9, wherein the minimum processing time of the PSFCH transmission is determined based on a last symbol of the PSSCH and a first symbol of the PSFCH.

12. The terminal according to claim 9, wherein: The terminal is configured to: when multiple PSFCHs are to be sent, determine the PSFCH to be sent among the multiple PSFCHs based on PSSCH sequences corresponding to the multiple PSFCHs or quality of service QoS of the PSSCHs.

13. The terminal according to claim 9, wherein: The terminal is configured to: in case a plurality of PSFCHs are to be transmitted: determining the transmit power of the PSFCH, and When the sum of the transmit powers of the PSFCHs exceeds the maximum available power of the terminal, the transmit powers of the PSFCHs are adjusted according to a preconfigured ratio.

14. The terminal according to claim 9, wherein: The terminal is configured to: in case a plurality of PSFCHs are to be transmitted: The PSFCH to be transmitted is determined based on at least one of a plurality of HARQ feedback bits of each PSFCH or based on information related to whether the PSFCH is a feedback transmission of a multicast transmission.

15. The terminal according to claim 9, The maximum number of bits of the HARQ feedback information is determined to be N+K-1 The minimum number of bits of the HARQ feedback information is determined to be a larger value between N-K+1 and 0, in, In the case where multiple PSFCHs are transmitted for PSSCHs transmitted from different terminals, the PSFCH corresponding to unicast transmission takes precedence over the PSFCH corresponding to multicast transmission, and The frequency band of the PSFCH is configured to be larger than the frequency band of the PSSCH.

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