Apparatus and method for terminal to process sidelink transmission in wireless communication system

Abstract

The present disclosure relates to a communication technique and a system for integrating a 5G communication system with IoT technology to support higher data transmission rates than those of a 4G system. The present disclosure may be applied to intelligent services (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail, security and safety-related services, etc.) based on 5G communication technology and IoT-related technology. According to a method for a terminal to process a sidelink transmission in a wireless communication system according to one embodiment of the present disclosure, the terminal may select a sidelink transmission resource pool, select a sidelink transmission resource from the selected transmission resource pool, and configure a MAC PDU and a transmission block to use the selected transmission resource.

Description

Technology Field

[0001] The present disclosure relates to a wireless communication system, and more specifically, to a method and apparatus for a terminal to process a sidelink transmission in a wireless communication system. Background Technology

[0002] 4G(4 th To meet the increasing demand for wireless data traffic following the commercialization of the (generation) communication system, improved 5G (5 th Efforts are being made to develop 5G communication systems or pre-5G communication systems. For this reason, 5G communication systems or pre-5G communication systems are referred to as Beyond 4G Network communication systems or Post-LTE systems.

[0003] To achieve high data transmission rates, 5G communication systems are being considered for implementation in the mmWave band (e.g., the 60 GHz band). To mitigate path loss and increase the transmission distance of radio waves in the mmWave band, beamforming, massive MIMO, full Dimensional MIMO (FD-MIMO), array antenna, analog beamforming, and large-scale antenna technologies are being discussed for 5G communication systems.

[0004] In addition, to improve the network of the system, technologies such as advanced small cell, advanced small cell, cloud radio access network (cloud RAN), ultra-dense network, Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation are being developed in 5G communication systems.

[0005] In addition, advanced coding modulation (ACM) methods such as FQAM (Hybrid Frequency Shift Keying and Quadrature Amplitude Modulation) and SWSC (Sliding Window Superposition Coding), as well as advanced access technologies such as FBMC (Filter Bank Multi Carrier), NOMA (Non Orthogonal Multiple Access), and SCMA (Sparse Code Multiple Access) are being developed in 5G systems.

[0006] Meanwhile, the Internet is evolving from a human-centered network where humans generate and consume information into an IoT (Internet of Things) network where distributed components, such as objects, exchange and process information. IoE (Internet of Everything) technology, which combines IoT with Big Data processing technologies through connections with cloud servers, is also emerging. To implement IoT, technological elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required; consequently, technologies such as sensor networks, Machine-to-Machine (M2M) communication, and Machine-Type Communication (MTC) are currently being researched to facilitate the connection of objects. In an IoT environment, intelligent IT services that create new value for human life by collecting and analyzing data generated from connected objects can be provided. Through the convergence and integration of existing IT technologies with various industries, IoT can be applied to fields such as smart homes, smart buildings, smart cities, smart or connected cars, smart grids, healthcare, smart home appliances, and advanced medical services.

[0007] Accordingly, various attempts are being made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, Machine to Machine (M2M), and Machine Type Communication (MTC) are being implemented using 5G communication techniques such as beamforming, MIMO, and array antennas. The application of cloud RAN as a big data processing technology, as previously described, can also be considered an example of the convergence of 5G and IoT technologies.

[0008] In addition, sidelink communication using 5G communication systems is being researched, and it is expected that this sidelink communication will be applied, for example, to vehicle-to-everything (V2X) communication to provide various services to users.

[0009] In order to provide various services in a 5G system, an efficient method for processing Sidelink data transmission and reception is currently being researched. The problem to be solved

[0010] The present disclosure provides an apparatus and method for a terminal in a wireless communication system to acquire a transmission resource and process a transport block to be included in the acquired transmission resource. means of solving the problem

[0011] According to one embodiment of the present disclosure, a method for processing a control signal in a wireless communication system comprises: receiving a first control signal transmitted from a base station; processing the received first control signal; and transmitting a second control signal generated based on the processing to the base station. Effects of the invention

[0012] According to embodiments of the present disclosure, by providing a method for selecting a sidelink transmission resource pool of a terminal, the effect of efficiently supporting sidelink flows with various QoS profiles and mixed QoS profiles set can be obtained. Brief explanation of the drawing

[0013] FIG. 1 illustrates a wireless communication system according to one embodiment of the present disclosure. FIG. 2 illustrates the configuration of a base station in a wireless communication system according to one embodiment of the present disclosure. FIG. 3 illustrates the configuration of a terminal in a wireless communication system according to an embodiment of the present disclosure. FIG. 4 illustrates the configuration of a communication unit in a wireless communication system according to one embodiment of the present disclosure. FIG. 5 illustrates the structure of a wireless time-frequency resource of a wireless communication system according to one embodiment of the present disclosure. FIG. 6a is a diagram showing a scenario for side-link communication according to one embodiment of the present disclosure. FIG. 6b is a diagram showing a scenario for side-link communication according to one embodiment of the present disclosure. FIG. 6c is a diagram showing a scenario for side-link communication according to one embodiment of the present disclosure. FIG. 6d is a diagram showing a scenario for side-link communication according to one embodiment of the present disclosure. FIG. 7a is a drawing for explaining a transmission method of side link communication according to one embodiment of the present disclosure. FIG. 7b is a drawing for explaining a transmission method of side link communication according to one embodiment of the present disclosure. FIG. 8a is a diagram showing the operation of a terminal processing a side link transmission according to one embodiment of the present disclosure. FIG. 8b is a diagram illustrating the operation of a terminal selecting a sidelink transmission resource according to one embodiment of the present disclosure. FIG. 9 is a diagram illustrating the operation of a terminal selecting a sidelink transmission resource pool according to one embodiment of the present disclosure. FIG. 10 is a diagram showing the operation of a terminal selecting a sidelink transmission resource pool according to one embodiment of the present disclosure. Specific details for implementing the invention

[0014] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that identical components in the accompanying drawings are represented by the same reference numerals whenever possible. Furthermore, detailed descriptions of known functions and configurations that may obscure the essence of the present disclosure will be omitted.

[0015] In describing the embodiments in this specification, descriptions of technical details that are well known in the technical field to which this disclosure belongs and are not directly related to this disclosure are omitted. This is intended to convey the essence of this disclosure more clearly without obscuring it by omitting unnecessary explanations.

[0016] For the same reason, some components in the attached drawings have been exaggerated, omitted, or schematically depicted. Additionally, the size of each component does not entirely reflect its actual dimensions. Identical or corresponding components in each drawing have been assigned the same reference numbers.

[0017] The advantages and features of the present disclosure and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below but may be implemented in various different forms. The embodiments provided are merely to ensure that the disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the disclosure is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components.

[0018] At this time, it will be understood that each block of the process flow diagrams and combinations of the flow diagrams can be executed by computer program instructions. Since these computer program instructions can be loaded into the processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, the instructions executed through the processor of the computer or other programmable data processing equipment create means to perform the functions described in the flow diagram block(s). Since these computer program instructions can also be stored in computer-available or computer-readable memory that can be directed toward the computer or other programmable data processing equipment to implement the function in a specific way, the instructions stored in computer-available or computer-readable memory can also produce a manufactured item containing the means of instruction to perform the function described in the flow diagram block(s). Since computer program instructions can be loaded onto a computer or other programmable data processing equipment, instructions that perform a series of operation steps on the computer or other programmable data processing equipment to create a process executed by the computer can also provide steps for executing the functions described in the flowchart block(s).

[0019] Additionally, each block may represent a module, segment, or part of code containing one or more executable instructions for executing a specified logical function(s). It should also be noted that in some alternative execution examples, the functions mentioned in the blocks may occur out of order. For instance, two blocks described in succession may actually be executed substantially simultaneously, or the blocks may be executed in reverse order according to their corresponding functions.

[0020] In this embodiment, the term "part" refers to a software or hardware component, such as an FPGA or ASIC, and the "part" performs certain roles. However, the meaning of "part" is not limited to software or hardware. The "part" may be configured to reside in an addressable storage medium or configured to operate one or more processors. Accordingly, as an example, the "part" includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and "parts" may be combined into a smaller number of components and "parts" or further separated into additional components and "parts." Furthermore, the components and "parts" may be implemented to operate one or more CPUs within a device or secure multimedia card.

[0021] In describing the embodiments of the present disclosure in detail, the focus is primarily on the New RAN (NR) wireless access network and the packet core (5G System, or 5G Core Network, or NG Core: Next Generation Core) of the 5G mobile communication standard specified by 3GPP, a mobile communication standardization organization; however, the main point of the present disclosure can be applied to other communication systems having a similar technical background with slight modifications without significantly departing from the scope of the present disclosure, and this will be possible at the judgment of a person with skilled technical knowledge in the technical field of the present disclosure.

[0022] In a 5G system, a network data collection and analysis function (NWDAF) can be defined to support network automation, which is a network function that provides the ability to analyze and provide data collected from a 5G network. The NWDAF can collect, store, and analyze information from the 5G network and provide the results to unspecified network functions (NFs), and the analysis results can be used independently by each NF.

[0023] For convenience of explanation below, some terms and names defined in 3GPP (3rd generation partnership project long term evolution) standards (specifications for 5G, NR, LTE, or similar systems) may be used. However, this disclosure is not limited to the terms and names of this disclosure and may be applied equally to systems conforming to other standards.

[0024] The present disclosure relates to an apparatus and method for a terminal to process sidelink transmission in a wireless communication system. Specifically, the present disclosure describes a method in which a terminal determines a mode for selecting a sidelink transmission resource itself, selects a sidelink transmission resource pool, acquires a sidelink transmission resource from the selected transmission resource pool, constructs a MAC PDU to utilize the acquired sidelink transmission resource, and constructs a transmission block.

[0025] According to one embodiment of the present disclosure, the terminal can achieve the effect of efficiently supporting sidelink flows configured for service purposes of various QoS profiles and mixed QoS profiles by operating various HARQ retransmission modes.

[0026] Terms referring to signals, channels, control information, network entities, and device components used in the following description are examples provided for the convenience of explanation. Accordingly, the present disclosure is not limited to the terms used herein, and other terms referring to objects having equivalent technical meanings may be used.

[0027] In the following description, the terms "physical channel" and "signal" may be used interchangeably with "data" or "control signal." For example, PDSCH (physical downlink shared channel) is a term referring to a physical channel through which data is transmitted, but PDSCH may also be used to refer to data. That is, in this disclosure, the expression "transmits a physical channel" may be interpreted as equivalent to the expression "transmits data or a signal through a physical channel."

[0028] In the present disclosure, upper signaling refers to a signal transmission method transmitted from a base station to a terminal using a physical layer downlink data channel, or from a terminal to a base station using a physical layer uplink data channel. Upper signaling may be understood as radio resource control (RRC) signaling or a media access control (MAC) control element (CE).

[0029] Additionally, in this disclosure, expressions such as "greater than" or "less than" have been used to determine whether specific conditions are satisfied or fulfilled; however, this is merely for illustrative purposes and does not exclude descriptions of "greater than" or "less than." Conditions described as "greater than" may be replaced with "greater than," conditions described as "less than" with "less than," and conditions described as "greater than and less than" with "greater than and less than."

[0030] Additionally, the present disclosure describes embodiments using terms used in some communication standards (e.g., 3GPP (3rd generation partnership project)), but this is merely an example for illustrative purposes. Embodiments of the present disclosure can be easily modified and applied to other communication systems.

[0031] FIG. 1 illustrates a wireless communication system according to one embodiment of the present disclosure.

[0032] FIG. 1 illustrates a base station (110), a terminal (120), and a terminal (130) as part of nodes utilizing a wireless channel in a wireless communication system. FIG. 1 illustrates only one base station, but other base stations identical or similar to the base station (110) may be included.

[0033] A base station (110) is a network infrastructure that provides wireless access to terminals (120, 130). The base station (110) has coverage defined as a certain geographical area based on the distance at which it can transmit signals. In addition to being a base station, the base station (110) may be referred to as an 'access point (AP)', 'eNodeB (eNB)', '5G node (5th generation node)', 'next generation nodeB (gNB)', 'wireless point', 'transmission / reception point (TRP)', or other terms having an equivalent technical meaning.

[0034] Each of the first terminal (120) and the second terminal (130) is a device used by a user and communicates with the base station (110) via a wireless channel. The link from the base station (110) toward the first terminal (120) or the second terminal (130) is referred to as a downlink (DL), and the link from the first terminal (120) or the second terminal (130) toward the base station (110) is referred to as an uplink (UL). Additionally, the first terminal (120) and the second terminal (130) can communicate with each other via a wireless channel. In this case, the link between the first terminal (120) and the second terminal (130) is referred to as a sidelink, and the sidelink may also be referred to as a PC5 interface. In some cases, at least one of the first terminal (120) and the second terminal (130) may be operated without user involvement. That is, at least one of the first terminal (120) and the second terminal (130) is a device that performs machine type communication (MTC) and may not be carried by a user. Each of the first terminal (120) and the second terminal (130) may be referred to as 'user equipment (UE)', 'mobile station', 'subscriber station', 'remote terminal', 'wireless terminal', or 'user device', or other terms having an equivalent technical meaning, in addition to 'terminal'.

[0035] The base station (110), the first terminal (120), and the second terminal (130) can transmit and receive wireless signals in the millimeter wave (mmWave) band (e.g., 28 GHz, 30 GHz, 38 GHz, 60 GHz). At this time, to improve channel gain, the base station (110), the first terminal (120), and the second terminal (130) can perform beamforming. Here, beamforming may include transmission beamforming and reception beamforming. That is, the base station (110), the first terminal (120), and the second terminal (130) can impart directivity to the transmission signal or the reception signal. To this end, the base station (110) and terminals (120, 130) can select serving beams (112, 113, 121, 131) through a beam search or beam management procedure. After the serving beams (112, 113, 121, 131) are selected, subsequent communication can be performed through a resource that is in a quasi-co-located (QCL) relationship with the resource that transmitted the serving beams (112, 113, 121, 131).

[0036] If large-scale characteristics of the channel transmitting the symbol on the first antenna port can be inferred from the channel transmitting the symbol on the second antenna port, the first antenna port and the second antenna port may be evaluated to have a QCL relationship. For example, the large-scale characteristics may include at least one of a delay spread, a Doppler spread, a Doppler shift, an average gain, an average delay, and a spatial receiver parameter.

[0037] The first terminal (120) and the second terminal (130) illustrated in FIG. 1 can support vehicle communication. In the case of vehicle communication, standardization work for V2X (vehicle-to-everything) technology based on the device-to-device (D2D) communication structure in LTE systems was completed in 3GPP Release 14 and Release 15, and efforts to develop V2X technology based on 5G NR are currently underway. NR V2X is expected to support unicast communication, groupcast (or multicast) communication, and broadcast communication between terminals. Furthermore, unlike LTE V2X, which is intended for transmitting and receiving basic safety information necessary for vehicle road driving, NR V2X aims to provide more advanced services such as platooning, advanced driving, extended sensors, and remote driving.

[0038] V2X services can be classified into basic safety services and advanced services. Basic safety services may include detailed services ranging from vehicle alerts (CAM (cooperative awareness messages) or BSM (basic safety message)) to left-turn alerts, front collision warnings, emergency vehicle approach alerts, forward obstacle warnings, and intersection signal information services; V2X information can be transmitted and received using broadcast, unicast, or groupcast transmission methods. Advanced services not only have stricter QoS (quality of service) requirements than basic safety services but also require methods to transmit and receive V2X information using unicast and groupcast transmission methods in addition to broadcast, enabling transmission and reception within a specific vehicle group or between two vehicles. Advanced services may include detailed services such as platooning services, autonomous driving services, remote driving services, and extended sensor-based V2X services.

[0039] Hereinafter, the sidelink (SL) refers to the signal transmission and reception path between terminals, and may be used interchangeably with the PC5 interface. Hereinafter, the base station is the entity that performs resource allocation for terminals and may be a base station that supports both V2X communication and general cellular communication, or a base station that supports only V2X communication. That is, the base station may refer to an NR base station (e.g., gNB), an LTE base station (e.g., eNB), or an RSU (road site unit). A terminal may include general user equipment and mobile stations, as well as vehicles supporting vehicular-to-vehicular (V2V) communication, vehicles or pedestrian handsets (e.g., smartphones) supporting vehicular-to-pedestrian (V2P) communication, vehicles supporting vehicular-to-network (V2N) communication, vehicles supporting vehicular-to-infrastructure (V2I) communication, and RSUs equipped with terminal functions, RSUs equipped with base station functions, or RSUs equipped with some base station functions and some terminal functions. Additionally, the V2X terminal used in the following description may also be referred to as a terminal. That is, in relation to V2X communication, a terminal may be used as a V2X terminal.

[0040] The base station and the terminal are connected through the Uu interface. The uplink (UL) refers to the wireless link through which the terminal transmits data or control signals to the base station, and the downlink (DL) refers to the wireless link through which the base station transmits data or control signals to the terminal.

[0041] FIG. 2 illustrates the configuration of a base station in a wireless communication system according to one embodiment of the present disclosure. The configuration illustrated in FIG. 2 can be understood as the configuration of a base station (110). Terms such as '... unit', '... unit' used below refer to a unit that processes at least one function or operation, and this can be implemented in hardware or software, or a combination of hardware and software.

[0042] Referring to FIG. 2, the base station (110) includes a wireless communication unit (210), a backhaul communication unit (220), a storage unit (230), and a control unit (240).

[0043] The wireless communication unit (210) performs functions for transmitting and receiving signals through a wireless channel. For example, the wireless communication unit (210) performs a conversion function between a baseband signal and a bit sequence according to the physical layer specifications of the system. For example, when transmitting data, the wireless communication unit (210) generates complex symbols by encoding and modulating the transmitted bit sequence. Also, when receiving data, the wireless communication unit (210) restores the received bit sequence by demodulating and decoding the baseband signal.

[0044] Additionally, the wireless communication unit (210) upconverts a baseband signal into an RF (radio frequency) band signal and transmits it through an antenna, and downconverts the RF band signal received through the antenna into a baseband signal. To this end, the wireless communication unit (210) may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC (digital to analog converter), an ADC (analog to digital converter), etc. Additionally, the wireless communication unit (210) may include a plurality of transmission and reception paths. Furthermore, the wireless communication unit (210) may include at least one antenna array composed of a plurality of antenna elements.

[0045] In terms of hardware, the wireless communication unit (210) may be composed of a digital unit and an analog unit, and the analog unit may be composed of a plurality of sub-units depending on operating power, operating frequency, etc. The digital unit may be implemented with at least one processor (e.g., a digital signal processor (DSP)).

[0046] The wireless communication unit (210) transmits and receives signals as described above. Accordingly, all or part of the wireless communication unit (210) may be referred to as a 'transmitter', a 'receiver', or a 'transceiver'. Furthermore, in the following description, transmission and reception performed through a wireless channel are used to mean that processing as described above is performed by the wireless communication unit (210).

[0047] The backhaul communication unit (220) provides an interface for communicating with other nodes within the network. That is, the backhaul communication unit (220) converts a bit sequence transmitted from the base station (110) to another node, e.g., another connection node, another base station, an upper node, a core network, etc., into a physical signal, and converts a physical signal received from another node into a bit sequence.

[0048] The storage unit (230) stores data such as basic programs, application programs, and configuration information for the operation of the base station (110). The storage unit (230) may be composed of volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory. Additionally, the storage unit (230) provides the stored data upon the request of the control unit (240).

[0049] The control unit (240) controls the overall operations of the base station (110). For example, the control unit (240) transmits and receives signals through the wireless communication unit (210) or through the backhaul communication unit (220). Additionally, the control unit (240) writes and reads data to and from the storage unit (230). Furthermore, the control unit (240) can perform the functions of a protocol stack required by the communication standard. According to another embodiment, the protocol stack may be included in the wireless communication unit (210). To this end, the control unit (240) may include at least one processor. According to one embodiment, the control unit (240) may control the base station (110) to perform operations according to the embodiments described below.

[0050] FIG. 3 illustrates the configuration of a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0051] The configuration illustrated in FIG. 3 can be understood as a configuration of a terminal (120). Terms such as '...part', '...unit' used below refer to a unit that processes at least one function or operation, and this can be implemented as hardware or software, or a combination of hardware and software.

[0052] Referring to FIG. 3, the terminal (120) includes a communication unit (310), a storage unit (320), and a control unit (330).

[0053] The communication unit (310) performs functions for transmitting and receiving signals through a wireless channel. For example, the communication unit (310) performs a conversion function between a baseband signal and a bit sequence according to the physical layer specifications of the system. For example, when transmitting data, the communication unit (310) generates complex symbols by encoding and modulating the transmitted bit sequence. Also, when receiving data, the communication unit (310) restores the received bit sequence by demodulating and decoding the baseband signal. Additionally, the communication unit (310) upconverts the baseband signal into an RF band signal and transmits it through an antenna, and downconverts the RF band signal received through the antenna into a baseband signal. For example, the communication unit (310) may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc.

[0054] Additionally, the communication unit (310) may include a plurality of transmission and reception paths. Furthermore, the communication unit (310) may include at least one antenna array composed of a plurality of antenna elements. In terms of hardware, the communication unit (310) may be composed of a digital circuit and an analog circuit (e.g., a radio frequency integrated circuit (RFIC)). Here, the digital circuit and the analog circuit may be implemented as a single package. Additionally, the communication unit (310) may include a plurality of RF chains. Furthermore, the communication unit (310) may perform beamforming.

[0055] The communication unit (310) transmits and receives signals as described above. Accordingly, all or part of the communication unit (310) may be referred to as a 'transmitter', a 'receiver', or a 'transmitter / receiver'. Additionally, in the following description, transmission and reception performed via a wireless channel are used to mean that processing as described above is performed by the communication unit (310).

[0056] The storage unit (320) stores data such as basic programs, application programs, and setting information for the operation of the terminal (120). The storage unit (320) may be composed of volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory. Additionally, the storage unit (320) provides the stored data upon the request of the control unit (330).

[0057] The control unit (330) controls the overall operations of the terminal (120). For example, the control unit (330) transmits and receives signals through the communication unit (310). Additionally, the control unit (330) writes and reads data to and from the storage unit (320). Furthermore, the control unit (330) can perform the functions of the protocol stack required by the communication standard. To this end, the control unit (330) may include at least one processor or microprocessor, or be part of a processor. Additionally, part of the communication unit (310) and the control unit (330) may be referred to as a communication processor (CP). According to one embodiment, the control unit (330) can control the terminal (120) to perform operations according to the embodiments described below.

[0058] FIG. 4 illustrates the configuration of a communication unit in a wireless communication system according to one embodiment of the present disclosure.

[0059] FIG. 4 illustrates an example of a detailed configuration of the wireless communication unit (210) of FIG. 2 or the communication unit (310) of FIG. 3. Specifically, FIG. 4 illustrates components for performing beamforming as part of the wireless communication unit (210) of FIG. 2 or the communication unit (310) of FIG. 3.

[0060] Referring to FIG. 4, the wireless communication unit (210) or the communication unit (310) includes an encoding and modulation unit (402), a digital beamforming unit (404), a plurality of transmission paths (406-1 to 406-N), and an analog beamforming unit (408).

[0061] The encoding and modulation unit (402) performs channel encoding. For channel encoding, at least one of a low density parity check (LDPC) code, a convolution code, and a polar code may be used. The encoding and modulation unit (402) generates modulation symbols by performing constellation mapping.

[0062] The digital beamforming unit (404) performs beamforming on a digital signal (e.g., modulation symbols). To do this, the digital beamforming unit (404) multiplies the modulation symbols by beamforming weights. Here, the beamforming weights are used to change the magnitude and phase of the signal and may be referred to as a 'precoding matrix', 'precoder', etc. The digital beamforming unit (404) outputs the digitally beamformed modulation symbols to a plurality of transmission paths (406-1 to 406-N). At this time, according to the MIMO (multiple input multiple output) transmission technique, the modulation symbols may be multiplexed, or the same modulation symbols may be provided to a plurality of transmission paths (406-1 to 406-N).

[0063] Multiple transmission paths (406-1 to 406-N) convert digitally beamformed digital signals into analog signals. To this end, each of the multiple transmission paths (406-1 to 406-N) may include an inverse fast Fourier transform (IFFT) operation unit, a cyclic prefix (CP) insertion unit, a DAC, and an up-conversion unit. The CP insertion unit is intended for orthogonal frequency division multiplexing (OFDM) and may be excluded when other physical layer methods (e.g., filter bank multi-carrier (FBMC)) are applied. That is, the multiple transmission paths (406-1 to 406-N) provide independent signal processing processes for multiple streams generated through digital beamforming. However, depending on the implementation method, some of the components of the multiple transmission paths (406-1 to 406-N) may be used in common.

[0064] The analog beamforming unit (408) performs beamforming on the analog signal. To do this, the digital beamforming unit (404) multiplies the analog signals by beamforming weights. Here, the beamforming weights are used to change the magnitude and phase of the signal. Specifically, the analog beamforming unit (408) can be configured in various ways depending on the connection structure between the multiple transmission paths (406-1 to 406-N) and antennas. For example, each of the multiple transmission paths (406-1 to 406-N) can be connected to a single antenna array. As another example, the multiple transmission paths (406-1 to 406-N) can be connected to a single antenna array. As yet another example, the multiple transmission paths (406-1 to 406-N) can be adaptively connected to a single antenna array or connected to two or more antenna arrays.

[0065] FIG. 5 illustrates the structure of a wireless time-frequency resource of a wireless communication system according to one embodiment of the present disclosure.

[0066] Referring to Fig. 5, in the wireless resource domain, the horizontal axis represents the time domain and the vertical axis represents the frequency domain. The minimum transmission unit in the time domain is an OFDM symbol or a DFT-S-OFDM symbol, where N symb OFDM symbols or DFT-S-OFDM symbols (530) are contained in a single slot (505). Unlike slots, in an NR system, the length of a subframe can be defined as 1.0 ms, and the length of a radio frame (500) can be defined as 10 ms. The minimum transmission unit in the frequency domain is a subcarrier, and the bandwidth of the entire system transmission bandwidth is a total of N BW It may include several subcarriers (525). N symb , N BW Specific figures such as these may be applied variably depending on the system.

[0067] The basic unit of the time-frequency resource domain is the resource element (RE) (510), which can be represented as an OFDM symbol index or a DFT-S-OFDM symbol index and subcarrier index. The resource block (RB, 515) is N in the frequency domain. RB It can be defined as a series of consecutive subcarriers (520). Generally, the minimum transmission unit of data is an RB unit, and in an NR system, generally N symb = 14, N RB = 12.

[0068] The structure of a wireless time-frequency resource as shown in Fig. 5 is applied to the Uu interface. Additionally, the wireless time-frequency resource structure as shown in Fig. 5 can be similarly applied to a side link.

[0069] FIG. 6a illustrates an example of a scenario for side-link communication according to one embodiment of the present disclosure.

[0070] FIG. 6a illustrates an in-coverage scenario in which sidelink terminals (620a, 620b) are located within the coverage of a base station (610). The sidelink terminals (620a, 620b) may receive data and control information from the base station (610) via a downlink (DL) or transmit data and control information to the base station via an uplink (UL). In this case, the data and control information may be data and control information for sidelink communication or data and control information for general cellular communication other than sidelink communication. Additionally, in FIG. 6a, the sidelink terminals (620a, 620b) may transmit and receive data and control information for sidelink communication via a sidelink (SL).

[0071] FIG. 6b illustrates an example of a scenario for side-link communication according to one embodiment of the present disclosure.

[0072] Referring to FIG. 6b, a case of partial coverage is illustrated in which, among the sidelink terminals, the first terminal (620a) is located within the coverage of the base station (610) and the second terminal (620b) is located outside the coverage of the base station (610). The first terminal (620a), located within the coverage of the base station (610), can receive data and control information from the base station via a downlink or transmit data and control information to the base station via an uplink. The second terminal (620b), located outside the coverage of the base station (610), cannot receive data and control information from the base station via a downlink and cannot transmit data and control information to the base station via an uplink. The second terminal (620b) can transmit and receive data and control information for sidelink communication with the first terminal (620a) via a sidelink (SL).

[0073] FIG. 6c illustrates an example of a scenario for side-link communication according to one embodiment of the present disclosure.

[0074] Referring to FIG. 6c, this illustrates a case where sidelink terminals (e.g., a first terminal (620a), a second terminal (620b)) are located outside the coverage of a base station. Accordingly, the first terminal (620a) and the second terminal (620b) cannot receive data and control information from the base station via a downlink, nor can they transmit data and control information to the base station via an uplink. The first terminal (620a) and the second terminal (620b) can transmit and receive data and control information for sidelink communication via a sidelink (SL).

[0075] FIG. 6d illustrates an example of a scenario for side-link communication according to one embodiment of the present disclosure.

[0076] Referring to FIG. 6d, a first terminal (620a) and a second terminal (620b) performing sidelink communication can perform inter-cell sidelink communication with different base stations (e.g., first base station (610a), second base station (610b)) in a connected state (e.g., RRC connected state) or a camping state (e.g., RRC disconnected state, i.e., RRC idle state). In this case, the first terminal (620a) may be a sidelink transmitting terminal and the second terminal (620b) may be a sidelink receiving terminal. Alternatively, the first terminal (620a) may be a sidelink receiving terminal and the second terminal (620b) may be a sidelink transmitting terminal. The first terminal (620a) can receive a sidelink-only SIB (system information block) from the base station (610a) to which it is connected (or is camping), and the second terminal (620b) can receive a sidelink-only SIB from another base station (620b) to which it is connected (or is camping). At this time, the information in the sidelink-only SIB received by the first terminal (620a) and the information in the sidelink-only SIB received by the second terminal (620b) may be different from each other. Therefore, in order to perform sidelink communication between terminals located in different cells, it is necessary to unify the information.

[0077] In the examples of FIGS. 6a to 6d described above, for convenience of explanation, a side link system composed of two terminals (e.g., a first terminal (610a), a second terminal (620b)) was described as an example; however, the present disclosure is not limited thereto and may be applied to a side link system in which two or more terminals participate. Additionally, the uplink and downlink between the base station (610, 610a, 610b) and the side link terminals (620a, 620b) may be referred to as the Uu interface, and the side link between the side link terminals may be referred to as the PC-5 interface. In the following description, the uplink or downlink, the Uu interface, the side link, and the PC-5 may be used interchangeably.

[0078] Meanwhile, in the present disclosure, a terminal may refer to a vehicle supporting vehicular-to-vehicular (V2V) communication, a vehicle or pedestrian's handset (e.g., a smartphone) supporting vehicular-to-pedestrian (V2P) communication, a vehicle supporting vehicular-to-network (V2N) communication, or a vehicle supporting vehicular-to-infrastructure (V2I) communication. Additionally, in the present disclosure, a terminal may refer to a roadside unit (RSU) equipped with terminal functions, an RSU equipped with base station functions, or an RSU equipped with part of base station functions and part of terminal functions.

[0079] FIGS. 7a and 7b are drawings for explaining a transmission method of side link communication according to one embodiment of the present disclosure.

[0080] Specifically, FIG. 7a shows a unicast method, and FIG. 7b shows a groupcast method.

[0081] Referring to FIG. 7a, a transmitting terminal (720a) and a receiving terminal (720b) ​​can perform one-to-one communication. A transmission method like FIG. 7a may be referred to as unicast communication. Referring to FIG. 7b, a transmitting terminal (720a or 720d) and receiving terminals (720b, 720c, 720e, 720f, 720g) can perform one-to-many communication. A transmission method like FIG. 7b may be referred to as groupcast or multicast. In FIG. 7b, the first terminal (720a), the second terminal (720b), and the third terminal (720c) form a group and perform group cast communication, and the fourth terminal (720d), the fifth terminal (720e), the sixth terminal (720f), and the seventh terminal (720g) form another group and perform group cast communication. The terminals perform group cast communication within the group to which they belong and can perform unicast, group cast, or broadcast communication with at least one other terminal belonging to a different group. For convenience of explanation, two groups are shown in FIG. 7b, but the present disclosure is not limited thereto and may be applied even when a larger number of groups are formed.

[0082] Meanwhile, although not illustrated in FIG. 7a or FIG. 7b, sidelink terminals can perform broadcast communication. Broadcast communication refers to a method in which all sidelink terminals receive data and control information transmitted by a sidelink transmitting terminal through the sidelink. For example, if the first terminal (720a) in FIG. 7b is a transmitting terminal, the remaining terminals (720b, 720c, 720d, 720e, 720f, 720g) can receive data and control information transmitted by the first terminal (720a).

[0083] The aforementioned sidelink unicast communication, groupcast communication, and broadcast communication can be supported in in-coverage scenarios, partial-coverage scenarios, or out-of-coverage scenarios.

[0084] In the case of NR sidelinks, unlike LTE sidelinks, support for transmission methods in which a vehicle terminal transmits data to only one specific terminal via unicast and to multiple specific terminals via groupcast may be considered. For example, when considering service scenarios such as platooning, a technology in which two or more vehicles are connected to a single network and move as a cluster, these unicast and groupcast technologies can be effectively utilized. Specifically, a leader terminal of a group connected via platooning may use unicast communication to control one specific terminal, and groupcast communication may be used to simultaneously control a group consisting of multiple specific terminals.

[0085] In V2X systems, resource allocation can be performed using the following methods.

[0086] (1) Mode 1 resource allocation

[0087] Scheduled resource allocation is a method in which a base station allocates resources used for sidelink transmission to RRC-connected terminals using a dedicated scheduling method. Since the scheduled resource allocation method allows the base station to manage sidelink resources, it can be effective for interference management and resource pool management (dynamic allocation and / or semi-persistent transmission). If an RRC-connected terminal has data to transmit to other terminal(s), it can transmit information to the base station indicating that there is data to transmit to other terminal(s) using an RRC message or a MAC control element (hereinafter 'CE'). For example, the RRC message transmitted by the terminal to the base station may be a Sidelink UEInformation or UEAssistanceInformation message, and the MAC CE may be a BSR MAC CE, SR (scheduling request), etc., which includes at least one of an indicator indicating that it is a buffer status report (BSR) for V2X communication and information about the size of the data buffered for sidelink communication.

[0088] (2) Mode 2 Resource Allocation

[0089] Secondly, UE autonomous resource selection is a method in which a sidelink transmit / receive resource pool for V2X is provided to the terminal via system information or RRC messages (e.g., RRCReconfiguration message, PC5-RRC message), and the terminal selects resource pools and resources according to defined rules. UE autonomous resource selection may correspond to one or more of the following resource allocation methods.

[0090] The terminal autonomously selects a sidelink resource for transmission.

[0091] The terminal assists sidelink resource selection for other UEs.

[0092] The terminal receives the configured NR grant for sidelink transmission (UE is configured with NR configured grant for sidelink transmission).

[0093] A terminal can schedule sidelink transmission of other terminals (UE schedules sidelink transmission of other UEs).

[0094] - Resource selection methods for the terminal may include zone mapping, sensing-based resource selection, and random selection.

[0095] Additionally, even if the terminal is within the base station's coverage, resource allocation or resource selection may not be performed in a scheduled resource allocation or terminal autonomous resource selection mode; in such cases, the terminal may perform V2X sidelink communication through a preconfigured sidelink transmission and reception resource pool.

[0096] In addition, if terminals for V2X communication are located outside the base station's coverage area, the terminal may perform V2X sidelink communication through a pre-configured sidelink transmission and reception resource pool.

[0098] FIG. 8a is a diagram showing the operation of a terminal processing a side link transmission according to one embodiment of the present disclosure.

[0099] Referring to FIG. 8a above, the terminal can determine the sidelink transmission resource allocation mode at step 800. The sidelink transmission resource allocation mode can be set by the base station when the terminal is in the RRC_CONNECTED state, and can be set based on whether the terminal's RRC state is RRC_IDLE, RRC_INACTIVE, or OUT OF COVERAGE. At step 802, the terminal can determine whether the sidelink transmission resource allocation mode is Mode 1 resource allocation, that is, a mode where the base station allocates transmission resources, or Mode 2 resource allocation, that is, a mode where the terminal allocates transmission resources itself. If it is determined that it is Mode 1 resource allocation based on the determination at step 802, the terminal can proceed to step 804 to acquire transmission resources from the base station. If it is determined that it is Mode 2 resource allocation based on the determination at step 802, the terminal can proceed to step 806 to acquire transmission resources itself. The operation of the terminal acquiring transmission resources at step 806 will be explained with reference to FIG. 8b.

[0100] The terminal may perform a logical channel priority operation in step 808, which is an operation to determine the destination to use the transmission resources acquired in step 804 or 806 and one or more logical channels corresponding to said destination. In step 810, the terminal may construct a MAC PDU and construct a transmission block based on the packets of the selected destination and the corresponding logical channel. If the HARQ feedback setting of the selected destination and the corresponding logical channel is HARQ feedback enabled, the terminal may multiplex packets of one or more logical channels with HARQ feedback enabled set into one MAC PDU. The terminal may transmit the constructed MAC PDU and HARQ feedback enabled instruction information to its physical layer. If the HARQ feedback setting of the selected destination and the corresponding logical channel is HARQ feedback disabled, the terminal may multiplex packets of one or more logical channels with HARQ feedback disabled set into one MAC PDU. The terminal may transmit the constructed MAC PDU and HARQ feedback disabled instruction information to its physical layer.

[0101] FIG. 8b is a diagram illustrating the operation of a terminal selecting a sidelink transmission resource according to one embodiment of the present disclosure.

[0102] Referring to FIG. 8b, the terminal can select a transmission resource pool to be used for packet transmission in step 850. The detailed operation of the terminal selecting the transmission resource pool in step 850 will be explained with reference to FIGS. 9 and 10. The terminal can perform an operation to acquire a transmission resource from the transmission resource pool selected in step 850 in step 852. To acquire the transmission resource in step 852, the terminal can perform at least one of sensing-based resource selection or random resource selection.

[0103] FIG. 9 is a diagram illustrating the operation of a terminal selecting a sidelink transmission resource pool according to one embodiment of the present disclosure.

[0104] Based on the judgment criteria for selecting a transmission resource pool, if the selected logical channel is set to HARQ feedback enabled, the terminal selects a transmission resource pool with HARQ feedback resources enabled, and if the selected logical channel is set to HARQ feedback disabled, the terminal can select either a transmission resource pool with HARQ feedback resources enabled or a transmission resource pool without HARQ feedback resources enabled. Various embodiments in which the terminal selects a transmission resource pool satisfying HARQ feedback enabled or HARQ feedback disabled set on the logical channel will be described below with reference to FIG. 9.

[0105] Referring to FIG. 9 above, the terminal can select a logical channel that satisfies at least one or a combination of the following conditions at step 900.

[0106] (1) A logical channel containing data to be transmitted

[0107] (2) The logical channel with the highest transmission priority

[0108] (3) Logical channel where the SBj parameter (token of the sidelink transmission buffer) value is greater than 0

[0109] The terminal determines whether there is a transmission resource pool identical to the HARQ feedback setting configured on the logical channel selected in step 902, and can select the transmission resource pool identical to the HARQ feedback setting. If the HARQ feedback setting configured on the selected logical channel is HARQ feedback enabled, the terminal can select a transmission resource pool in which a HARQ feedback resource is configured. If the HARQ feedback setting configured on the selected logical channel is HARQ feedback disabled, the terminal can select a transmission resource pool in which a HARQ feedback resource is not configured. In another embodiment, if the HARQ feedback setting configured on the selected logical channel is HARQ feedback disabled, and the terminal determines that there is no transmission resource pool in which a HARQ feedback resource is not configured, the terminal can select a transmission resource pool in which a HARQ feedback resource is configured. In another embodiment, if the HARQ feedback setting configured on the selected logical channel is HARQ feedback disabled, the terminal can select one of a transmission resource pool in which a HARQ feedback resource is configured or a transmission resource pool in which a HARQ feedback resource is not configured as a transmission resource pool. If there is one or more logical channels satisfying the judgment condition of step 900 above and the HARQ feedback settings for the logical channels are set differently (i.e., some are set to HARQ feedback enabled, some are set to HARQ feedback disabled), the terminal can select a transmission resource pool in which the HARQ feedback resource is set.

[0110] If the terminal determines that one or more transmission resource pools satisfy the conditions of step 902, it may, as an example, arbitrarily select one transmission resource pool. As an example, the terminal may select the transmission resource pool with the lowest channel busy ratio (CBR). As an example, the terminal may select a transmission resource pool with a channel busy ratio lower than a set threshold. As an example, the terminal may arbitrarily select a transmission resource pool with a channel busy ratio lower than a set threshold. As an example, the terminal may select a transmission resource pool with a channel busy ratio lower than a set threshold and the lowest channel busy ratio value.

[0111] The terminal may perform the operation of selecting a transmission resource based on sensing or randomly from the transmission resource pool selected in step 902 in step 904.

[0112] The terminal can perform an operation in step 906 to determine whether the SL grant obtained in step 904 is HARQ feedback enabled or HARQ feedback disabled.

[0113] In one embodiment, if at step 906 the terminal determines that the transmission resource pool selected at step 902 is selected by a logical channel set to HARQ feedback enabled and that the transmission resource of step 904 is acquired from this resource pool, the terminal may determine at step 908 that the corresponding SL grant is HARQ feedback enabled. If at step 906 the terminal determines that the transmission resource pool selected at step 902 is selected by a logical channel set to HARQ feedback disabled and that the transmission resource of step 904 is acquired from this resource pool, the terminal may determine at step 910 that the corresponding SL grant is HARQ feedback disabled.

[0114] As another embodiment, if the terminal determines in step 906 that a HARQ feedback resource is set in the transmission resource pool selected in step 902 and that the transmission resource of step 904 is acquired from this resource pool, the terminal may determine in step 908 that the corresponding SL grant is HARQ feedback enabled. If the terminal determines in step 906 that a HARQ feedback resource is not set in the transmission resource pool selected in step 902 and that the transmission resource of step 904 is acquired from this resource pool, the terminal may determine in step 910 that the corresponding SL grant is HARQ feedback disabled.

[0115] FIG. 10 is a diagram showing the operation of a terminal selecting a sidelink transmission resource pool according to one embodiment of the present disclosure.

[0116] Referring to FIG. 10 above, the terminal can select a transmission resource pool in which a HARQ feedback resource is configured at step 1000. The terminal can obtain an SL grant from the selected transmission resource pool at step 1002. The SL grant can be used on either a logical channel in which the HARQ feedback setting is HARQ feedback enabled or a logical channel in which the HARQ feedback setting is HARQ feedback disabled.

[0117] If the terminal determines in step 1000 that there is no transmission resource pool with a HARQ feedback resource set, the terminal may select a transmission resource pool without a HARQ feedback resource set and obtain an SL grant. The obtained SL grant may be used for a logical channel where the HARQ feedback setting is HARQ feedback disabled. The obtained SL grant may be used for either a logical channel where the HARQ feedback setting is HARQ feedback disabled or a logical channel where the HARQ feedback setting is HARQ feedback enabled. In this case, for a HARQ feedback enabled logical channel, the terminal may arbitrarily treat it as if it were HARQ feedback disabled.

[0118] In step 1004, the terminal may perform a logical channel prioritization (LCP) procedure to select a logical channel to use the acquired SL grant. When the terminal performs the operation of selecting a logical channel to use the selected SL grant, if the logical channel with the highest transmission priority is set to HARQ feedback enabled, the terminal may use the SL grant by selecting one or more logical channels set to HARQ feedback enabled. Alternatively, if it is determined that the logical channel with the highest transmission priority is set to HARQ feedback disabled, the terminal may use the SL grant by selecting one or more logical channels set to HARQ feedback disabled.

[0119] When a terminal performs an operation to select a transmission resource pool according to the embodiments of FIGS. 9 and 10, the terminal may handle a case where a HARQ feedback resource is not set in the transmission resource pool, and the terminal operation may include at least one of the following.

[0120] (1) A terminal can select a transmission resource from a pool of transmission resources where no HARQ feedback resource is set, and can determine that the selected transmission resource is HARQ feedback disabled. The transmission resource corresponding to the HARQ feedback disabled can be used for packet transmission belonging to a logical channel where the HARQ feedback setting is set to HARQ feedback disabled. If the HARQ feedback setting of the logical channel selected by the terminal is set to HARQ feedback enabled, the terminal can skip packet transmission belonging to a logical channel where the HARQ feedback setting is set to HARQ feedback enabled.

[0121] (2) The terminal may select a transmission resource from a pool of transmission resources where no HARQ feedback resource is set, and may determine that the selected transmission resource is HARQ feedback disabled. If the HARQ feedback setting of the logical channel selected by the terminal is set to HARQ feedback enabled, the terminal may ignore the HARQ feedback setting of the logical channel and arbitrarily process the HARQ feedback setting of the logical channel as if it were HARQ feedback disabled. The transmission resource corresponding to the above HARQ feedback disabled may be used for packet transmission belonging to a logical channel where the HARQ feedback setting is set to HARQ feedback disabled and a logical channel that the terminal arbitrarily processes as being set to HARQ feedback disabled.

[0122] According to an embodiment of the present invention, the operation of a terminal re-selecting a transmission resource pool is as follows.

[0123] The terminal can determine the HARQ feedback setting of the logical channel selected for transmission. The terminal can determine whether the HARQ feedback setting of the selected logical channel is set to HARQ feedback enabled or HARQ feedback disabled. If the terminal determines that the HARQ feedback setting of the logical channel selected for transmission is HARQ feedback disabled, and that the HARQ feedback resource is not configured in the previously selected transmission resource pool and is being used for packet transmission of a logical channel configured to HARQ feedback disabled, the terminal may determine to continue using the previously selected transmission resource pool. If the terminal determines that the HARQ feedback setting of the logical channel selected for transmission is HARQ feedback enabled, and that the HARQ feedback resource is not configured in the previously selected transmission resource pool and is being used for packet transmission of a logical channel configured to HARQ feedback disabled, the terminal may determine to perform the operation of selecting a new transmission resource pool, that is, a transmission resource pool in which the HARQ feedback resource is configured.

[0124] If the terminal determines that a HARQ feedback resource is configured in the previously selected transmission resource pool and determines that the HARQ feedback setting of the logical channel selected for transmission is HARQ feedback disabled, it may decide to continue using the previously selected transmission resource pool.

[0125] If the terminal determines that a HARQ feedback resource is configured in the previously selected transmission resource pool and determines that the HARQ feedback setting of the logical channel selected for transmission is HARQ feedback disabled, it may determine to perform the operation of selecting a new transmission resource pool, that is, a transmission resource pool in which a HARQ feedback resource is not configured.

[0126] If the terminal determines that a HARQ feedback resource is configured in the previously selected transmission resource pool and determines that the HARQ feedback setting of the logical channel selected for transmission is HARQ feedback enabled, it may decide to continue using the previously selected transmission resource pool.

[0127] As an embodiment of the present invention, even when it is determined to continue using a previously selected transmission resource pool based on the HARQ feedback setting of a logical channel, the terminal may perform a transmission resource pool re-selection procedure if at least one or a combination of the following cases is satisfied.

[0128] (1) When the CBR value of the transmission resource pool is determined to be higher than the CBR threshold set for the terminal (or logical channel)

[0129] (2) When it is determined that the CR (channel occupancy ratio) limit value set for the terminal (or logical channel) in the transmission resource pool has been exceeded (i.e., there is a limit on the CR value that the terminal (or logical channel) can use in the transmission resource pool)

[0130] (3) When it is determined that the CR limit set for the terminal (or logical channel) in the transmission resource pool has been exceeded (i.e., there is a limit on the CR value that can be used for the transmission resource pool for the terminal (or logical channel))

[0131] According to various embodiments of the present invention, the operation performed by a terminal selecting a logical channel to transmit a packet using an SL grant obtained from a selected transmission resource pool is as follows.

[0132] (1) Example 1

[0133] If the terminal determines that an SL grant has been obtained from a transmission resource pool in which a HARQ feedback resource is configured, the terminal may select a destination identifier corresponding to the logical channel with the highest transmission priority or MAC CE that satisfies the following conditions.

[0134] - A logical channel with data to transmit (pending data)

[0135] - Logical channels with an SBj parameter value greater than 0

[0136] - Logical channel set to HARQ feedback enabled

[0137] - If there are no logical channels set to HARQ feedback enabled, logical channels set to HARQ feedback disabled

[0138] The terminal can select a logical channel that satisfies the following among the logical channels belonging to the selected destination identifier.

[0139] - Logical channel containing data to be transmitted

[0140] - Logical channel set to HARQ feedback enabled

[0141] - If there are no logical channels set to HARQ feedback enabled, logical channels set to HARQ feedback disabled

[0142] Alternatively, if the terminal determines that the SL grant was obtained from a transmission resource pool where no HARQ feedback resource is configured, the terminal may select a destination identifier corresponding to the logical channel with the highest transmission priority or MAC CE that satisfies the following conditions.

[0143] - A logical channel containing data to be transmitted

[0144] - Logical channels with an SBj parameter value greater than 0

[0145] - Logical channel with HARQ feedback disabled

[0146] The terminal can select a logical channel that satisfies the following among the logical channels belonging to the selected destination identifier.

[0147] - Logical channel containing data to be transmitted

[0148] - Logical channel with HARQ feedback disabled

[0149] (2) Example 2

[0150] If the terminal determines that the SL grant is HARQ feedback enabled, the terminal may select a destination identifier corresponding to the logical channel with the highest transmission priority or MAC CE that satisfies the following conditions.

[0151] - A logical channel with data to transmit (pending data)

[0152] - Logical channels with an SBj parameter value greater than 0

[0153] - Logical channel set to HARQ feedback enabled

[0154] - If there are no logical channels set to HARQ feedback enabled, logical channels set to HARQ feedback disabled

[0155] The terminal can select a logical channel that satisfies the following among the logical channels belonging to the selected destination identifier.

[0156] - Logical channel containing data to be transmitted

[0157] - Logical channel set to HARQ feedback enabled

[0158] - If there are no logical channels set to HARQ feedback enabled, logical channels set to HARQ feedback disabled

[0159] Alternatively, if the terminal determines that the SL grant is HARQ feedback disabled, the terminal may select a destination identifier corresponding to the logical channel with the highest transmission priority or MAC CE that satisfies the following conditions.

[0160] - A logical channel containing data to be transmitted

[0161] - Logical channels with an SBj parameter value greater than 0

[0162] - Logical channel with HARQ feedback disabled

[0163] The terminal can select a logical channel that satisfies the following among the logical channels belonging to the selected destination identifier.

[0164] - Logical channel containing data to be transmitted

[0165] - Logical channel with HARQ feedback disabled

[0166] (3) Example 3

[0167] The terminal can select a transmission resource pool that satisfies the logical channel condition with the highest transmission priority and the HARQ feedback setting condition, and obtain an SL grant from this resource pool.

[0168] The terminal may select a destination identifier corresponding to the logical channel or MAC CE with the highest transmission priority that satisfies the following conditions.

[0169] - A logical channel with data to transmit (pending data)

[0170] - Logical channels with an SBj parameter value greater than 0

[0171] The terminal can select a logical channel that satisfies the following among the logical channels belonging to the selected destination identifier.

[0172] - Logical channel containing data to be transmitted

[0173] - If the highest priority logical channel is set to HARQ feedback enabled, the logical channel set to HARQ feedback enabled

[0174] - If the highest priority logical channel is set to HARQ feedback disabled, the logical channel set to HARQ feedback disabled

[0175] Methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0176] When implemented in software, a computer-readable storage medium may be provided for storing one or more programs (software modules). One or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. One or more programs include instructions that cause the electronic device to execute methods according to the embodiments described in the claims or specification of this disclosure.

[0177] These programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), magnetic disc storage devices, CD-ROM (Compact Disc-ROM), Digital Versatile Discs (DVDs), or other forms of optical storage devices, magnetic cassettes. Alternatively, they may be stored in memory composed of some or all of these. Additionally, each constituent memory may include multiple units.

[0178] Additionally, the program may be stored on an attachable storage device accessible via a communication network such as the Internet, Intranet, Local Area Network (LAN), Wide LAN (WLAN), or Storage Area Network (SAN), or a combination thereof. Such a storage device may be connected to the device performing the embodiment of the present disclosure through an external port. Additionally, a separate storage device on the communication network may be connected to the device performing the embodiment of the present disclosure.

[0179] In the specific embodiments of the present disclosure described above, the components included in the disclosure are expressed in a singular or plural form according to the specific embodiments presented. However, the singular or plural expression is selected to suit the situation presented for convenience of explanation, and the present disclosure is not limited to singular or plural components; even if a component is expressed in the plural form, it may be composed of a singular form, and even if a component is expressed in the singular form, it may be composed of a plural form.

[0180] Meanwhile, although specific embodiments have been described in the detailed description of the present disclosure, it is understood that various modifications are possible within the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments, but should be defined by the claims set forth below as well as equivalents thereof.

Claims

Claim 1 A method of a terminal in a wireless communication system comprises: a step of checking a hybrid automatic repeat request (SL) feedback setting for a first logical channel having sidelink (SL) data; a step of selecting a first resource pool containing SL HARQ feedback resources from among resource pools set for SL transmission if the SL HARQ feedback setting for the first logical channel is set to enabled, and selecting one resource pool from among the resource pools if the SL HARQ feedback setting for the first logical channel is set to disabled; a step of selecting a resource from the selected first resource pool or the selected one resource pool; a step of selecting at least one logical channel to use the selected resource from among logical channels belonging to the destination of the SL transmission; and a step of generating a medium access control (MAC) protocol data unit (PDU) containing data from the selected at least one logical channel. A method of a terminal comprising the step of transmitting the MAC PDU to the destination using the selected resource, wherein the one resource pool is a second resource pool that does not include the first resource pool or the SL HARQ feedback resources, and if the resource is selected from the first resource pool, the at least one logical channel includes a second logical channel selected based on the SL HARQ feedback setting of the logical channel having the highest priority among the logical channels, and if the resource is selected from the second resource pool, the at least one logical channel includes a third logical channel among the logical channels in which the SL HARQ feedback setting is set to impossible. Claim 2 A method of a terminal according to claim 1, wherein the second logic channel is selected as the logic channel among the logic channels where the SL HARQ feedback setting is enabled when the SL HARQ feedback setting of the logic channel having the highest priority among the logic channels is set to enabled, and is selected as the logic channel among the logic channels where the SL HARQ feedback setting is disabled when the SL HARQ feedback setting of the logic channel having the highest priority among the logic channels is set to disabled. Claim 3 A method of a terminal according to claim 1, wherein the terminal is set to side link resource allocation mode 2, and the resource is selected based on arbitrary selection or sensing. Claim 4 A method of a terminal characterized by further including the step of receiving configuration information for the resource pools from a base station in claim 1. Claim 5 A method of a terminal according to claim 4, wherein the above-mentioned setting information is received through a radio resource control (RRC) message or system information. Claim 6 In a terminal device of a wireless communication system, a transmitting and receiving unit; The method includes a control unit that checks the SL HARQ (hybrid automatic repeat request) feedback setting for a first logical channel having sidelink (SL) data, and if the SL HARQ feedback setting for the first logical channel is set to enabled, selects a first resource pool containing SL HARQ feedback resources from among resource pools set for SL transmission, and if the SL HARQ feedback setting for the first logical channel is set to disabled, selects one resource pool from among the resource pools, selects a resource from the selected first resource pool or the selected one resource pool, selects at least one logical channel to use the selected resource from among the logical channels belonging to the destination of the SL transmission, generates a MAC (medium access control) PDU (protocol data unit) containing data from the selected at least one logical channel, and controls the transceiver to transmit the MAC PDU to the destination using the selected resource, wherein the one resource pool does not include the first resource pool or the SL HARQ feedback resources. A terminal device characterized in that, if the resource is selected from the first resource pool, the at least one logical channel includes a second logical channel selected based on the SL HARQ feedback setting of the logical channel having the highest priority among the logical channels, and if the resource is selected from the second resource pool, the at least one logical channel includes a third logical channel among the logical channels where the SL HARQ feedback setting is set to impossible. Claim 7 A terminal device according to claim 6, wherein the control unit selects the logical channel among the logical channels in which the SL HARQ feedback setting is enabled as the second logical channel when the SL HARQ feedback setting of the logical channel having the highest priority among the logical channels is enabled, and selects the logical channel among the logical channels in which the SL HARQ feedback setting is disabled as the second logical channel when the SL HARQ feedback setting of the logical channel having the highest priority among the logical channels is disabled. Claim 8 A terminal device according to claim 6, wherein the terminal device is set to side link resource allocation mode 2, and the control unit selects the resource based on arbitrary selection or sensing. Claim 9 A terminal device according to claim 6, wherein the control unit controls the transceiver to receive configuration information for the resource pools from the base station. Claim 10 A terminal device according to claim 9, characterized in that the above-mentioned setting information is received through a radio resource control (RRC) message or system information.

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