Method and device for determining sidelink physical layer session identification

Abstract

The invention provides a method and an apparatus for determining a sidelink physical layer session identifier in a wireless communication system, and specifically provides a method for transmitting feedback information through a terminal in an NR V2X system. The method for transmitting feedback information may comprise: a step in which a first terminal performs a session establishment procedure with a second terminal on the basis of at least one of unicast and multicast; a step in which the first terminal and the second terminal exchange ID information with each other during the session establishment process; and a step of completing the session establishment by the first terminal and the second terminal. When the first terminal and the second terminal complete the session establishment, a physical layer ID representing a session may be determined.

Description

This application is a divisional application of Chinese Patent Application No. 202080008673.5, filed on January 8, 2020, entitled "Method and Apparatus for Determining Sidelink Physical Layer Session Identity in a Wireless Communication System", the contents of which are hereby incorporated by reference. TECHNICAL FIELD

[0001] The disclosure relates to a method and apparatus for determining a sidelink physical layer session identity (ID) in a wireless communication system, and more particularly, to a method and apparatus for determining a sidelink layer-1 ID for vehicle-to-everything (V2X) communication in a wireless communication system.

[0002] RELATED ART

[0003] The International Telecommunication Union (ITU) has developed an International Mobile Telecommunication (IMT) framework and standards. Also, discussions for 5th-Generation (5G) communication are being made through a project called "IMT for 2020 and Beyond".

[0004] In order to meet the requirements required by "IMT for 2020 and Beyond", various parameters (numerology) regarding a time-frequency resource unit standard are being discussed by considering various scenarios, service requirements, and potential system compatibility in a 3rd-Generation Partnership Project (3GPP) New Radio (NR) system.

[0005] Vehicle-to-everything (V2X) communication can be a communication method of exchanging or sharing road infrastructure and information (e.g., traffic situation) by communicating with other vehicles during driving. V2X can include, for example, vehicle-to-vehicle (V2V) which can be long term evolution (LTE)-based communication between vehicles, vehicle-to-pedestrian (V2P) which can be LTE-based communication between a vehicle and a user equipment (UE) carried by a user, and vehicle-to-infrastructure / network (V2I / N) which can be LTE-based communication between a vehicle and a road side unit (RSU) / network. Here, the RSU can be a transportation infrastructure entity configured by a base station or a fixed terminal, for example, an entity that transmits a speed notification to a vehicle. DETAILED DESCRIPTION TECHNICAL TASK

[0007] One aspect of the disclosure provides a method and apparatus for determining a physical layer session identity (ID) in a wireless communication system.

[0008] One aspect of the disclosure also provides a method and apparatus for determining a physical layer session ID in a new radio (NR) vehicle-to-everything (V2X) system.

[0009] An aspect of the disclosure provides a method and apparatus that can determine a physical layer session ID according to quality of service (QoS) requirements in an NR V2X system to perform sidelink communication.

[0010] An aspect of the disclosure provides a method and apparatus that determines a physical sidelink feedback channel (PSFCH) format in an NR V2X system.

[0011] An aspect of the disclosure provides a method and apparatus that determines a PSFCH structure in an NR V2X system.

[0012] Other objects and advantages of the disclosure can be understood by the following description, and will be more clearly understood from the example of the disclosure. Furthermore, it will be easily understood that the objects and advantages of the disclosure can be achieved by the means presented in the claims and combinations thereof.

[0013] Technical solutions

[0014] To achieve these objects, according to one aspect of the disclosure, there is provided a method of transmitting feedback information from a user equipment (UE) in a new radio (NR) vehicle-to-everything (V2X) system. Here, the method of transmitting feedback information can include performing, by a first UE and a second UE, a session establishment procedure based on at least one of unicast and groupcast, exchanging ID information by the first UE and the second UE in the session establishment procedure, and completing, by the first UE and the second UE, the session establishment. Here, when the first UE and the second UE complete the session establishment, a physical layer ID representing a session can be determined.

[0015] Effects

[0016] According to the disclosure, a physical layer session identification (ID) can be determined in a wireless communication system.

[0017] According to the disclosure, a physical layer session ID in a new radio (NR) vehicle-to-everything (V2X) system can be determined.

[0018] According to the disclosure, a physical layer session ID can be determined according to quality of service (QoS) requirements in an NR V2X system to perform sidelink communication.

[0019] According to the disclosure, a physical sidelink feedback channel (PSFCH) format in an NR V2X system can be determined.

[0020] According to an aspect of the disclosure, a PSFCH structure in an NR V2X system can be determined.

[0021] Effects achievable by the disclosure are not limited to the above-described effects, and other effects not explicitly discussed herein can be clearly understood by those skilled in the art from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 An example of a frame structure for downlink / uplink transmissions is shown in accordance with examples of the present disclosure.

[0024] Figure 2 An example of a resource grid and resource blocks is shown in accordance with examples of the present disclosure.

[0025] Figure 3 An example of a system architecture is shown in accordance with examples of the present disclosure.

[0026] Figure 4 An example of a scenario for performing New Radio (NR) Vehicle-to-Everything (V2X) sidelink communication in a 3rd Generation Partnership Project (3GPP) network is shown in accordance with examples of the present disclosure.

[0027] Figure 5 An example of a method of determining a physical layer session ID is shown in accordance with examples of the present disclosure.

[0028] Figure 6 An example of an environment in which multiple unicast and / or groupcast exist is shown in accordance with examples of the present disclosure.

[0029] Figure 7 An example of a method of determining a physical layer session ID for unicast is shown in accordance with examples of the present disclosure.

[0030] Figure 8 An example of a method of determining a physical layer session ID for groupcast is shown in accordance with examples of the present disclosure.

[0031] Figure 9 An example of a method of performing sidelink communication based on a physical layer session ID is shown in accordance with examples of the present disclosure.

[0032] Figure 10 An example of an environment in which multiple unicast and / or groupcast exist is shown in accordance with examples of the present disclosure.

[0033] Figure 11 An example of a method of determining a physical sidelink feedback channel (PSFCH) format is shown in accordance with examples of the present disclosure.

[0034] Figure 12 An example of a method of determining a PSFCH format is shown in accordance with examples of the present disclosure.

[0035] Figure 13 An example of a method of determining a PSFCH format is shown in accordance with examples of the present disclosure.

[0036] Figure 14An example of a method of determining a physical layer session ID according to an example of the present disclosure is shown.

[0037] Figure 15 A structural example diagram of a base station apparatus and a terminal apparatus of the present disclosure is shown.

[0038] Best mode for carrying out the invention

[0039] To achieve this object, according to an aspect of the present disclosure, there is provided a method of transmitting feedback information from a user equipment (UE) in a new radio (NR) vehicle-to-everything (V2X) system. Here, the method of transmitting feedback information can include performing, by a first UE and a second UE, a session establishment procedure based on at least one of unicast and groupcast; exchanging, by the first UE and the second UE, ID information in the session establishment procedure; and completing, by the first UE and the second UE, the session establishment. Here, when the first UE and the second UE complete the session establishment, a physical layer ID representing a session is determined. DETAILED DESCRIPTION

[0041] Various examples of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings, in which these examples can be easily carried out by a person skilled in the art to which the present disclosure pertains. However, the present disclosure can be implemented in various forms, and is not limited to the examples described herein.

[0042] In describing examples of the present disclosure, detailed descriptions of known configurations or functions can be omitted for clarity and conciseness. Throughout the drawings and detailed description, unless otherwise specified, the same reference numerals will be understood to refer to the same elements, features, and structures.

[0043] It should be understood that when an element is referred to as being "connected to", "coupled to" or "accessed" another element, it can be directly connected, coupled or accessed to the other element or intervening elements can be present. In addition, it will be understood that when an element is described as "including" or "having" another element, it specifies the presence of the other element but does not preclude the presence of additional elements otherwise described.

[0044] In addition, terms such as first, second, etc. can be used herein to describe elements in the description. These terms are used to distinguish one element from another. Thus, the terms do not limit the elements, the order of arrangement, the sequence, etc. Thus, a first element in one example can be referred to as a second element in another example. Likewise, a second element in one example can be referred to as a first element in another example.

[0045] Here, providing the distinguished elements is merely for clearly explaining the respective features, and does not mean that the elements must be separated from each other. That is, a plurality of elements can be integrated into a single hardware or software unit. Also, a single element can be distributed to a plurality of hardware or software units. Accordingly, unless particularly described otherwise, the integrated or distributed example also includes in the scope of the present disclosure.

[0046] Here, the elements described in various examples can not be necessarily essential, and can be partially selectable. Accordingly, an example including a part of the elements described in the examples also includes in the scope of the present disclosure. Further, an example additionally including another element other than the elements described in various examples also includes in the scope of the present disclosure.

[0047] Further, the descriptions described herein relate to a wireless communication network, and operations performed in the wireless communication network can be performed in a process of controlling the network and transmitting data by a system (e.g., a base station) controlling the wireless network, or can be performed in a user equipment connected to the wireless communication network.

[0048] Obviously, in a network including a base station and a plurality of network nodes, various operations performed for communication with a terminal can be performed by the base station or other network nodes other than the base station. Here, the term "base station (BS)" can be used interchangeably with other terms, for example, a fixed station, a Node-B, an eNode-B (eNB), a gNode-B (gNB), and an access point (AP). Further, the term "terminal" can be used interchangeably with other terms, for example, a user equipment (UE), a mobile station (MS), a mobile subscriber station (MSS), a subscriber station (SS), and a non-AP station (non-AP STA).

[0049] Here, a transmission or reception channel includes the meaning of transmitting or receiving information or a signal through a corresponding channel. For example, transmitting a control channel means transmitting control information or a signal through a control channel. Likewise, transmitting a data channel means transmitting data information or a signal through a data channel.

[0050] In the following description, although the term "New Radio (NR) system" is used to distinguish the system according to various examples of the present disclosure from the existing system, the scope of the present disclosure is not limited thereto. Further, the term "NR system" used herein serves as an example of a wireless communication system capable of supporting various subcarrier spacings (SCSs). However, the term "NR system" itself is not limited to a wireless communication system supporting a plurality of SCSs.

[0051] Figure 1 An example of an NR frame structure and parameters according to examples of the present disclosure is shown.

[0052] In NR, the basic unit of time domain can be T c = 1 / (Δf max· N f ). Here, Δf max = 480 · 10 3 kHz and N f = 4096. Also, κ = T s / T c = 64 can be a constant with respect to a multiple relationship between the NR time unit and the LTE time unit. In LTE, T s = 1 / (Δf ref · N f,ref ), Δf ref = 15 · 10 3 kHz, and N f,ref = 2048 can be defined as a reference time unit.

[0054] Frame structure

[0055] Referring to Figure 1 , T f = (Δf max N f / 100) · T s = 10 ms can be included in a time structure of a frame for downlink / uplink (DL / UL) transmission. Here, a single frame can include 10 subframes corresponding to T sf = (Δf max N f / 1000) · T s = 1 ms. The number of consecutive orthogonal frequency division multiplexing (OFDM) symbols of each subframe can be Also, each frame can be divided into two half-frames, and the half-frames can include 0~4 subframes and 5~9 subframes. Here, half-frame 1 can include 0~4 subframes, and half-frame 2 can include 5~9 subframes.

[0056] Here, according to Equation 1 below, the transmission timing of an uplink transmission frame i is determined based on downlink reception timing at the UE.

[0057] In Equation 1, N TA,offset indicates a TA offset value that occurs due to a difference in duplex mode, etc. Basically, in frequency division duplex (FDD), N TA,offset = 0. In time division duplex (TDD), N TA,offset can be defined as a fixed value by considering a margin of a DL-UL switching time.

[0058] [Equation 1]

[0059] T TA = (N TA +N TA,offset )T c

[0060] Figure 2 An example of a resource grid and a resource block is shown.

[0061] Referring to Figure 2 Resource elements within the resource grid can be indexed based on each subcarrier spacing. Here, a single resource grid can be generated for each antenna port and each subcarrier spacing. Uplink / downlink transmission and reception can be performed based on the corresponding resource grid.

[0062] A single resource block can be configured with 12 resource elements in the frequency domain, and an index nRBGfor a single resource block can be configured every 12 resource elements PRB As expressed in Equation 2 below. The index of the resource block can be used for a specific frequency band or system bandwidth.

[0063] [Equation 2]

[0064]

[0066] Parameters Numerologies )

[0067] The parameters can be variously configured to satisfy various services and requirements of the NR system. In addition, referring to Table 1 below, the parameters can be defined based on an SCS used in an OFDM system, a cyclic prefix (CP) length, and the number of OFDM symbols per slot. The above values can be provided to a UE through upper layer parameters DL-BWP-mu and DL-BWP-cp (DL) and UL-BWP-mu and UL-BWP-cp (UL).

[0068] In addition, for example, referring to Table 1 below, if μ = 2 and SCS = 60 kHz, normal CP and extended CP can be applied. In other frequency bands, only normal CP can be applied.

[0069] [Table 1]

[0070] μ Δf = 2 μ • 15 [kHz]] Cyclic prefix 0 15 Normal 1 30 Normal 2 60 Normal, extended 3 120 Normal 4 240 Normal

[0071] Here, a normal slot can be defined as a basic time unit for transmitting a single piece of data and control information in the NR system. The length of the normal slot can basically include 14 OFDM symbols. In addition, unlike a slot, a subframe can have an absolute time length corresponding to 1 ms in the NR system, and can be used as a reference time for the length of another time period. Here, for coexistence and backward compatibility of the LTE and NR systems, the NR standard can require a time period such as an LTE subframe.

[0072] For example, in LTE, data can be transmitted based on a transmission time interval (TTI) as a unit of time. The TTI can include at least one subframe unit. Here, even in LTE, a single subframe can be set to 1 ms, and can include 14 OFDM symbols (or 12 OFDM symbols).

[0073] Further, in the NR system, a non-slot can be defined. The non-slot can refer to a slot having a number of symbols less than that of a normal slot by at least one symbol. For example, in the case of providing a low latency such as an ultra-reliable and low latency communication (URLLC) service, a latency can be reduced by a non-slot having a number of slots less than that of a normal slot. Here, the number of OFDM symbols included in the non-slot can be determined based on a frequency range. For example, a non-slot having a 1 OFDM symbol length in a frequency range of 6 GHz or more can be considered. As another example, a number of symbols used to define a non-slot can include at least two OFDM symbols. Here, the number of OFDM symbols included in the non-slot can be configured to have a mini-slot length of up to (normal slot length)-1. Here, although the number of OFDM symbols can be limited to 2, 4, or 7 as a non-slot standard, it is provided only as an example.

[0074] Further, for example, SCSs corresponding to μ=1 and 2 can be used in an unlicensed band of 6 GHz or less, and SCSs corresponding to μ=3 and 4 can be used in an unlicensed band of 6 GHz or more. Here, for example, if μ=4, it can be dedicated only to a synchronization signal block (SSB), which will be described below. However, it is provided only as an example and the disclosure is not limited thereto.

[0075] Further, Table 2 shows the number of OFDM symbols per slot of each SCS setting Table 2 shows the number of OFDM symbols per slot, the number of slots per frame, and the number of slots per subframe according to each SCS value, as provided in Table 1. Here, in Table 2, the values are based on a normal slot having 14 OFDM symbols.

[0076] [Table 2]

[0077]

[0078] Further, as described above, if μ=2 and SCS=60 kHz, an extended CP can be applied. In Table 3, in the case of an extended CP, the number of OFDM symbols per slot can be 12, and the number of slots per frame can be 10. Further, the number of slots per subframe can be 10. The number of 12 normal slots indicates each value. Here, Table 3 shows the number of symbols per slot, the number of slots per frame, and the number of slots per subframe in the case of an extended CP after SCS is 60 kHz.

[0079] [Table 3]

[0080]

[0081] Hereinafter, the structure of an SSB / Physical Broadcast Channel (PBCH) in an NR system and an initial cell access structure in the NR system are described.

[0082] Here, an NR base station (i.e., gNB) can periodically transmit signals and channels as shown in Table 4 below, to allow initial cell selection of a UE in a cell.

[0083] [Table 4]

[0084]

[0085] For example, the SS / PBCH block can be the aforementioned SSB. Here, even in the NR system, a UE can need to receive a broadcast channel for forwarding a synchronization signal and important system information transmitted from a corresponding wireless access system to perform initial wireless access. To this end, the UE can check reception sensitivity of a synchronization signal to discover a best cell existing in a best channel environment. The UE can perform a frequency / time synchronization and cell identification operation to perform initial access to a best channel in one or more channels in a specific frequency band based on the checked reception sensitivity operation. The UE can verify a boundary of OFDM symbol timing through the above-described operation, and then can initiate PBCH demodulation in the same SSB.

[0086] Here, the UE can receive a PBCH Demodulation Reference Signal (DMRS) and can perform PBCH demodulation. In addition, the UE can acquire 3-Lowest Significant Bit (LSB) information from SSB index information bits through the PBCH DMRS. The UE can acquire information included in a PBCH payload by performing PBCH demodulation. The UE can perform a process of demodulating SIB 1 based on information acquired through the PBCH.

[0087] For example, in the NR system, a UE can receive Remaining System Information (RMSI) as system information not transmitted from the PBCH through a broadcast signal or channel. In addition, the UE can receive Other System Information (OSI) and a paging channel as other additional system information through a broadcast signal or channel.

[0088] Hereinafter, the UE can access the base station through a random access channel (RACH) procedure and then perform mobility management.

[0089] In addition, for example, when the UE receives an SSB, the UE needs to set the SSB constitution and the SS burst set constitution.

[0091] NR V2X services

[0092] In association with the V2X service, the existing V2X service can support a set of basic requirements for the V2X service. Here, the requirements are basically designed with full consideration of road safety services. Accordingly, the V2X UE can exchange autonomous status information through a sidelink, and can exchange information with an infrastructure node and / or a pedestrian.

[0093] Meanwhile, in a further evolved service (e.g., LTE Rel-15) as the V2X service, new features are introduced by considering the feasibility of carrier aggregation in a sidelink, high-order modulation, reduced latency, transmit (Tx) diversity, and sTTI. Based on the above description, coexistence with the V2X UE (same resource pool) is required, and services are provided based on LTE.

[0094] For example, by considering a use case for supporting a new V2X service as a system aspect (SA) 1, technical features can be classified mainly based on four categories as represented by Table 5 below. Here, in Table 5, "vehicle platooning" can be a technology that enables a plurality of vehicles to dynamically form a group and operate identically. Also, "extended sensors" can be a technology that enables exchange of data collected from sensors or video images. Further, "advanced driving" can be a technology that enables vehicles to be based on semi-automated or fully-automated driving. Further, "remote driving" can be a technology for remotely controlling a vehicle and a technology for providing an application. Based on this, further descriptions related thereto are given through Table 5 below.

[0095] [Table 5]

[0096]

[0097] Further, the above-described SA1 can consider all of LTE and NR as an enhanced V2X (eV2X) support technology supporting a new V2X service. For example, the NR V2X system can be a first V2X system. Further, the LTE V2X system can be a second V2X system. That is, the NR V2X system and the LTE V2X system can be different V2X systems. Hereinafter, a method based on satisfying low latency and high reliability required in an NR sidelink based on the NR V2X system is described. Here, even in the LTE V2X system, the same or similar components can be extended and thereby applied. However, it is provided only as an example and the disclosure is not limited thereto. That is, even in the LTE V2X system, the disclosure can be applied to an interactable part, and is not limited to the following example. Here, for example, the NR V2X capability can not be limited to basically supporting only a V2X service, and a V2X RaT to be used can be selected.

[0099] NR sidelink

[0100] The NR sidelink can be used for the above-described NR V2X service. Here, for example, the NR sidelink frequency can consider FR1 as a frequency of 6 GHz or less and FR2 (e.g., up to 52.6 GHz) as a frequency exceeding 6 GHz. Further, for example, the NR sidelink frequency can consider all of unlicensed ITS bands and licensed ITS bands. That is, as described above, a general design method for supporting various frequency bands can be required. To this end, the NR sidelink design of the NR system can be required to be considered. For example, similar to the NR standard design, although it is not based on a beam, even if it is an omnidirectional Tx / Rx, an NR sidelink design capable of supporting beam-based transmission and reception can be basically required. However, it is provided only as an example.

[0101] Further, for example, a physical channel of the NR V2X sidelink can be set. For example, the NR physical sidelink shared channel (PSSCH) can be a data channel of the NR sidelink as a physical channel. Further, for example, the NR physical sidelink control channel (PSCCH) can be a control channel for the NR sidelink as a physical channel. Here, scheduling information and control information of the data channel of the NR sidelink can be forwarded through the NR PSCCH. For example, sidelink control information (SCI) can be transmitted based on defining a format of a field regarding control information associated with scheduling of the NR sidelink data channel, and control information transmitted through the NR PSCCH can be transmitted based on the SCI format.

[0102] Further, for example, an NR physical sidelink feedback channel (PSFCH) can be defined. Here, the NR PSFCH can be an NR hybrid automatic repeat request (HARQ) feedback channel as a physical channel. Here, HARQ-ACK feedback information, channel state information (CSI), and other information corresponding to an NR sidelink data channel can be forwarded through the NR PSFCH. In detail, sidelink feedback control information (SFCI) including feedback information can be forwarded through the NR PSFCH. Here, the SFCI can include information on at least one of HARQ-ACK, channel quality information (CQI), precoding matrix indicator (PMI), rank indicator (RI), reference signal received power (RSRP), reference signal received quality (RSRQ), path gain / path loss, scheduling request indicator (RSI), contention resolution identifier (CRI), interference condition, vehicle motion, etc. However, this is provided by way of example only and the present application is not limited thereto. Here, for example, the NR PSFCH is further described.

[0104] NR V2X QoS requirements

[0105] Considering the services of Table 5 above, the NR V2X QoS requirements can be a higher level than the existing V2X (e.g., LTE V2X) requirements, for example, based on Table 6 below, the delay can be set within 3ms to 100ms. And the reliability can be set between 90% and 99.999%. Also, a data rate of up to 1Gbps can be required.

[0106] [Table 6]

[0107]

[0108] That is, as described above, considering the V2X services, QoS requirements capable of satisfying low latency and high reliability can be required. Here, for example, access stratum (AS) level QoS management can be required to satisfy the QoS requirements. Further, for example, HARQ and CSI can be required to satisfy the QoS requirements considering link adaptation. Further, for example, the maximum bandwidth (maximum BW) capability can be different for each NR V2X UE. That is, AS level information exchange between UEs based on the above description is required. For example, the AS level information can include at least one of UE capability, QoS related information, radio bearer configuration, and physical layer configuration. Also, for example, the AS level information can further include other information. However, this is provided by way of example only and the present application is not limited thereto.

[0109] Table 7 below shows various terms used herein. However, this is provided by way of example only and the present application is not limited thereto.

[0110] [Table 7]

[0111]

[0112] NR sidelink design

[0113] NR V2X sidelink design is described to meet requirements of new evolved V2X (i.e., eV2X) services.

[0114] In detail, a synchronization procedure and method required to form a radio link of the NR sidelink are provided in detail. Here, it is assumed that the NR sidelink frequency for the NR sidelink operation is designed by considering all unlicensed ITS bands and licensed ITS bands and bands and ranges operated by the NR system of FR1 and FR2 (e.g., up to 52.6 GHz), and it is assumed that the NR sidelink frequency needs to be applicable to all FR1 and FR2 as a common design. In addition, for the NR V2X sidelink transmission and reception procedure, the availability of the LTE (ng-eNB) / NR Uu link (i.e., the above-described 3GPP NG-RAN) needs to be considered.

[0115] Designs for eV2X synchronization information transmission and signal transmission and reception to meet higher requirements from new evolved V2X services need to be considered. Here, unlike the legacy system (e.g., LTE), the frequency of the NR V2X SL communication based on the required technology in the new system can also consider at least one element in Table 8 below. By applying the NR V2X SL based on the NR wireless connection technology, especially the technology related to uplink transmission in Table 8 below, the requirements of new V2X need to be met.

[0116] In addition, in addition to Table 8 below, other factors can also be considered by considering the new system, and it is provided only as an example, and the present disclosure is not limited thereto.

[0117] [Table 8]

[0118]

[0119] In addition, the NR V2X sidelink physical channel and signal, and the basic slot structure and physical resource can show the corresponding items in Table 9 below.

[0120] [Table 9]

[0121]

[0122] In addition, Figure 3 Examples of considering the basic network architecture configuration and deployment scenario of the NR V2X sidelink are shown.

[0123] For example, referring to Figure 3 , the NG interface can be provided between the nodes 310-1 and 310-2 of the 5th generation core (5GC NW) and the nodes 320-1, 320-2, 330-1, and 330-2 of the NG-RAN. Also, the Xn interface can be provided between the nodes 320-1, 320-2, 330-1, and 330-2 of the NG-RAN. Here, in the above-described architecture, the corresponding nodes can be interconnected through the corresponding Xn interface based on the gNB (NR UP / CP protocol) corresponding to the nodes 320-1 and 320-2 and the ng-eNB (E-UTRA UP / CP protocol) corresponding to the nodes 330-1 and 330-2 constituting the NG-RAN. Also, as described above, in the 5GC, the corresponding nodes can be interconnected through the corresponding NG interface. Here, for example, in the above-described architecture, the LTE sidelink UE and the NR sidelink UE can all be controlled by the NG-RAN (e.g., LTE Uu and NR Uu) based on the gNB and the ng-eNB. Accordingly, when transmitting synchronization information, the NR sidelink UE can receive the synchronization information from the LTE Uu or the NR Uu link, and can transmit the NR sidelink synchronization information (e.g., SL synchronization signal / SL physical broadcast channel (PBCH)) based on the received synchronization information. However, this is provided only as an example and the disclosure is not limited thereto. That is, the NR sidelink UE can also acquire the synchronization information through the LTE Uu link as well as the NR Uu link.

[0124] Meanwhile, regarding the V2X sidelink communication, the V2X sidelink UE can perform the V2X sidelink communication. Here, predetermined conditions need to be satisfied so that the V2X sidelink UE can start the communication. These conditions can be represented by Table 10 below. That is, the V2X sidelink UE can perform the V2X sidelink communication in the RRC idle mode, the inactive mode, or the connected mode. Also, the V2X sidelink UE performing the V2X sidelink communication needs to be registered on a selected cell on a used frequency or needs to belong to the same public land mobile network (PLMN). Also, if the V2X sidelink UE is OOC on a frequency for the V2X sidelink communication, the V2X sidelink UE can perform the V2X sidelink communication only when it is possible to perform the V2X sidelink communication based on pre-configuration.

[0125] [Table 10]

[0126]

[0127] Here, as described above, in order to start V2X sidelink communication, sidelink synchronization information can be required. Therefore, the UE needs to transmit sidelink synchronization information. Here, the transmitting UE (sidelink Tx UE) can receive a configuration for transmitting sidelink synchronization information before transmitting the corresponding synchronization information. Here, for example, the transmitting UE can receive the configuration for transmitting the sidelink synchronization information based on a system information message or an RRC reconfiguration message (in the case of an RRC connected UE) broadcast from the above-described NG-RAN node. Further, for example, if an NR V2X sidelink UE (hereinafter, referred to as a UE) does not exist in the NG-RAN, the UE can transmit sidelink synchronization information based on preconfigured information, as described above.

[0128] Figure 4 An example of a scenario in which NR V2X sidelink communication is performed in a 3GPP network based on the foregoing description is illustrated. Here, NR V2X sidelink communication can be performed on a 3GPP network (hereinafter, NG-RAN). In addition, the presence of a global navigation satellite system (GNSS) signal can be considered.

[0129] In detail, referring to Figure 4 , each of the NR V2X sidelink UEs can be IC or OOC based on the ng-eNB 610, can be IC or OOC based on the gNB 620, and can also be IC or OOC based on the GNSS 630. Here, the NR V2X sidelink UEs can select a synchronization reference resource based on the location and capability of the UE. Further, for example, in addition to the scenario of Figure 6 , the scenario illustrated in Table 11 below can also be considered. However, it is provided only as an example and the present disclosure is not limited thereto.

[0130] [Table 11]

[0131]

[0132] Meanwhile, hereinafter, the NR SCS can refer to one of an SCS value of an NR DL SS / PBCH, an SCS value of an NR BWP (data / control channel), and a reference SCS value defined / set for comparison of an NR V2X SCS value. As another example, the NR SCS can refer to one of an SCS value of an NR V2X SLSS / PSBCH, an SCS value of an NR V2X BWP or resource pool (data / control channel), and a reference SCS value defined / set for comparison of an NR V2X SCS value. However, it is provided only as an example and the present disclosure is not limited thereto. Further, for example, a 30 kHz SCS value can be set as a default value and used for a 5.9 GHz ITS spectrum. However, it is provided only as an example and the present disclosure is not limited thereto.

[0133] In case of performing the NR V2X sidelink communication, data transmission can be performed based on unicast / groupcast. Here, for example, unicast transmission can refer to transmitting a message from a single UE to another UE, i.e., one-to-one transmission. In addition, broadcast transmission can refer to a scheme of transmitting a message to all UEs regardless of whether Rx UEs support a service. That is, a single UE can transmit a message regardless of whether multiple Rx UEs support a service. Meanwhile, the groupcast transmission scheme can be a scheme of transmitting a message to multiple UEs belonging to a group.

[0134] Here, for example, whether to activate unicast, groupcast, or broadcast data transmission and reception and whether to perform session connection can be determined in an upper layer. That is, although a physical layer of a V2X UE can operate based on an instruction determined in an upper layer, it is provided by way of example only, and the disclosure is not limited thereto.

[0135] In addition, for example, a V2X UE can perform respective transmission and reception after forming a session for respective unicast or groupcast data transmission. When a V2X UE performs transmission and reception based on the aforementioned session, physical layer parameter information for data transmission corresponding to unicast or groupcast can be known in advance in a physical layer of the V2X UE. For example, the V2X UE can receive and identify the aforementioned information in advance from a base station. As another example, the aforementioned information can be information preset to the V2X UE. Here, for example, unicast or groupcast data transmission and reception can be applied only to a case where there are a relatively small number of V2X UEs around a Tx V2X UE and a session is stably maintained. In addition, if a session is not stable or if neighboring V2X UEs vary greatly, data transmission can be performed based on broadcast transmission. Here, it is provided by way of example only, and the disclosure is not limited thereto.

[0136] In addition, for example, as described above, unicast or groupcast transmission and reception can be determined in an application layer terminal as an upper layer. Here, for example, data that can be allocated to transmission and reception generated in the application layer can not be directly mapped to a radio layer. Here, for example, in case of performing unicast or groupcast transmission and reception, a mapping relationship or a connection establishment procedure can be required to perform data transmission and reception on a radio layer. However, it is provided by way of example only, and the disclosure is not limited thereto.

[0137] Further, for example, in case of performing unicast data transmission and reception, the corresponding Tx and Rx UEs can need to establish a session by performing a procedure of discovering their presence (e.g., a discovery procedure), and such session establishment can be performed based on various methods. Here, the session establishment between the UEs can be performed with the assistance of a base station. The base station can collect location information of the UEs, and can determine whether the UEs capable of performing unicast or groupcast data transmission and reception are adjacent to each other. Here, for example, the base station can determine whether the UEs are adjacent to each other based on a threshold. Here, the threshold can be determined using a predetermined value. When the UEs in a cell are determined to be adjacent to each other, the base station can initialize a corresponding discovery procedure, and the UEs can perform the corresponding discovery procedure to discover each other based on the initialization procedure. Further, the base station can determine whether there are adjacent V2X SL UEs by designing a new discovery channel and by periodically transmitting and receiving the corresponding channel. Further, the base station can determine whether there are adjacent UEs by transmitting a corresponding discovery message on a V2X data channel. However, this is provided by way of example only and the disclosure is not limited thereto. That is, the session establishment for unicast or groupcast data transmission and reception can be completed based on the above-described procedures. Subsequently, the upper layer can inform the physical layer of information about the session establishment, and can perform physical layer operations such as HARQ-ACK, CSI, and link adaptation.

[0139] PSFCH for sidelink communication

[0140] As described above, a PSFCH for feedback information transmission can be set. For example, in case of performing NR V2X sidelink communication, the UE can perform transmission based on unicast and / or groupcast. Here, a physical layer ID for unicast and / or groupcast transmission and reception can be generated. Further, the UE can provide feedback information through the PSFCH based on the above-described physical layer ID. For example, as described above, high reliability and low latency operation can be required to meet the requirements of services provided through NR V2X sidelink communication. Therefore, even in sidelink communication, it is necessary to construct and provide feedback information. Hereinafter, a PSFCH construction method is described based on the above description. For example, the PSFCH structure can consider all channel structures based on a sequence and channel structures in the form of a payload (modulation symbol), which will be described below. Further, the PSFCH can include sidelink feedback control information (SFCI). Here, the SFCI can include information about Table 12 below by considering sidelink unicast and / or groupcast transmission and reception. That is, the SFCI can include HARQ-ACK information, channel state information (CSI), and signal-related information.

[0141] [Table 12]

[0142]

[0143] Here, the HARQ-ACK information can be included in feedback information (e.g., SFCI) for unicast and / or groupcast transmission performed on a sidelink. For example, if only HARQ-ACK is included in the feedback information, a small number of bits can be used to configure the PSFCH. Here, 1 bit or 2 bits can be used to configure the PSFCH. However, this is provided only as an example. Also, a large number of bits can be used to configure the PSFCH. For example, referring to Table 12, the SFCI can include CSI feedback information for link adaptation and multiple-input multiple-output (MIMO) transmission. Further, for example, HARQ-ACK bits corresponding to a plurality of TBs can exist on at least one slot. Here, the SFCI can include HARQ-ACK bit information corresponding to a plurality of TBs, and the number of bits can be increased based on the information.

[0144] That is, the SFCI size can be differently set based on at least one of a scenario, a transmission scheme, and a related configuration on an NR V2X sidelink communication. Here, as described above, at least one PSFCH transmission format can be required to efficiently handle variously changed SFCI sizes.

[0145] Here, based on the above description, the format of the PSFCH can be set to a format for forwarding SFCI of less than 2 bits or a format for forwarding SFCI of more than 2 bits. For example, if the size of the SFCI is less than or equal to 2 bits, the PSFCH format can consider a sequence-based format or a modulation symbol-based format. This will be further described below.

[0147] Sidelink connection management procedures and signaling

[0148] For example, the sidelink connection management procedure can include at least one of connection establishment, connection release, connection maintenance, and security activation. As described above, the NR V2X can support unicast and / or groupcast transmission. Thus, a connection management procedure can be required between UEs involving unicast and / or groupcast transmission. For example, the sidelink connection management procedure can be performed through a PC5 signaling protocol in an application layer. Further, by considering an AS layer connection management procedure, release, maintenance, and management can be performed for an AS layer connection. In detail, AS parameter configuration can be performed by applying a channel measurement result related thereto, such that a specific AS layer operation (e.g., HARQ, CSI, etc.) of the AS layer connection can be performed on the AS layer for the AS layer connection. Here, PC5-RRC can be required. Here, the PC5-RRC can refer to signaling and configuration between RRC layers generated between UEs performing sidelink V2X communication. That is, the PC5-RRC refers to an existing RRC, and can be distinguished from an RRC layer for a Uu link (a link between a base station and a UE). Here, for example, the sidelink connection management procedure can be performed in an upper layer level. That is, a procedure regarding connection establishment between UEs can be performed in an upper layer level. Here, for example, the NR V2X can additionally perform a sidelink connection management procedure in an AS layer level. Here, when the sidelink connection management procedure is additionally performed in the AS layer level, the PC5-RRC can be set.

[0149] For example, in LTE, a connection for unicast transmission between D2D UEs can be generated by a PC5 signaling protocol after a discovery procedure. Further, a session or a connection for groupcast transmission is not generated. A radio bearer can not be generated in a one-to-one communication setup set for unicast transmission. Further, a one-to-one layer 2 link between UEs performing one-to-one communication can be distinguished by a combination of layer-2 IDs of the UEs. Here, a UE can be included in a plurality of layer 2 links for one-to-one communication using the same layer 2 ID. In a D2D connection for existing one-to-one communication, AS layer information exchange is not performed. The PC5 signaling protocol can be used to set a one-to-one layer 2 link between UEs. Here, for example, PC5-S refers to a PC5 signaling protocol stack, and can be performed based on a control plane signal over a PC5 interface for configuration, maintenance, and release of a direct link between two UEs. Here, in legacy LTE (e.g., LTE D2D), a PC5-S signal can be designated for connection management, and can be used for connection management such as a direct connection configuration, maintenance, and release procedure, or a security mode such as a security mode procedure. Therefore, in the case of PC5-S, it can not be possible to exclude AS layer parameter configuration of security-related parameters. Here, for example, in NR V2X, there can be a plurality of unicast and / or groupcast connections (or sessions), and a high QoS can be required compared to existing systems. By considering the above-described cases, an ID value per connection can be required, which will be described below.

[0151] SL layer-1 ID for unicast and / or groupcast transmission

[0152] For example, as described above, the SL layer-1 ID value for guaranteeing efficiency and reliability of unicast and / or groupcast-based NR V2X communication can be defined in the physical layer. That is, a physical layer ID for sidelink communication can be defined. Here, for clarity of description, although the SL layer-1 ID is used, it is provided only as an example. That is, the SL layer-1 ID can indicate a physical layer ID for sidelink communication, and can also be designated using another name. Here, for example, as described above, high QoS requirements can be required in NR V2X. Thus, the UE can need to perform HARQ-ACK feedback, link adaptation, or CSI feedback operations in the physical layer. Also, the UE can perform another operation by considering the high QoS requirements required in NR V2X. But the disclosure is not limited thereto. Here, for example, it can be necessary to set the SL layer-1 ID for the aforementioned UE operations. In existing V2X (e.g., LTE V2X), only broadcast transmission is supported, as described above. Thus, the layer-1 ID value is determined and used based on 16-bit cyclic redundancy check (CRC) information attached to SCI in PSCCH. Further, in LTE D2D, the layer-1 ID value can generally be used in a physical channel based on a destination ID (for layer-1) provided from a Tx UE to an Rx UE in SCI.

[0153] In contrast, as described above, unlike the existing case, NR V2X needs to support data transmission with further various and high QoS requirements in the physical layer. Further, by considering this aspect, sidelink unicast and / or groupcast transmission can be performed. That is, each UE can additionally perform unicast and / or groupcast transmission as well as the existing broadcast-based sidelink transmission. For example, traffic requiring high reliability and latency can generally use unicast transmission. Here, since unicast communication is one-to-one communication, there can be more unicast connections (UE pairs for unicast) compared to the existing sidelink system. That is, various types of sidelink communication can be performed based on high QoS requirements within a limited communication range, and thus, transmission guaranteeing physical layer reliability needs to be supported. Hereinafter, a method of setting the aforementioned SL layer-1 ID value to effectively support NR V2X communication by considering the above aspect will be described. Here, all physical layer channels and signals corresponding to unicast and / or groupcast transmission and PSFCH can perform transmission and reception using the SL layer-1 ID value used in the physical layer. That is, unicast transmission can be performed using a unicast layer-1 ID value. Further, groupcast transmission can be performed using a groupcast layer-1 ID value. However, it is provided only as an example and the disclosure is not limited thereto.

[0154] Figure 5 An example of a method of determining the SL layer-1 ID value when a single session is established through sidelink between UEs is shown. For example, referring to Figure 5, the first UE (UE 1) 510 and the second UE (UE 2) 520 can perform a session connection through a unicast session connection procedure. When connecting a unicast session, the first UE 510 and the second UE 520 can perform unicast V2X communication through at least one resource pool. Here, for example, a single unicast ID value representing a one-to-one connection between UEs can be mapped in each resource pool. Also, for example, at least one unicast ID value can be mapped between two UEs in a single resource pool. That is, a resource pool available for a single unicast transmission can be set based on the above mapping relationship. Here, for example, the above unicast ID can be a layer-2 ID. Here, the layer-2 ID refers to an ID value for layer 2, and can be used to identify at least one unicast layer-2 link between two UEs. For example, referring to Figure 5 The layer-2 ID can be generated through a combination of layer-2 IDs (e.g., layer-2 destination ID, layer-2 source ID) of the first UE 510 and the second UE 520. That is, when a session is established between the first UE 510 and the second UE 520, an ID representing the session between the first UE 510 and the second UE 520 can be generated in an upper layer.

[0155] Also, for example, a single groupcast ID (group ID) value representing a one-to-many UE connection can be mapped in each resource pool. Also, for example, at least one groupcast ID value can be mapped between UEs in a single resource pool. That is, a resource pool available for a single groupcast transmission can be set based on the above mapping relationship. Here, for example, the above groupcast ID can be a layer-2 ID. Here, the layer-2 ID refers to an ID value for layer 2, and can be used to identify at least one groupcast layer-2 link between UEs, which represents a connection between UEs in a group.

[0156] For example, referring to Figure 5 The layer-2 ID can be generated through a combination of layer-2 IDs (e.g., layer-2 destination / source ID) of the first UE 510 and the second UE 520. That is, when a session is established between the first UE 510 and the second UE 520, an ID representing the session between the first UE 510 and the second UE 520 can be generated in an upper layer.

[0157] Here, for example, an ID for identifying each unicast and / or groupcast physical link can be required on a physical layer. In detail, an ID for identifying each unicast and / or groupcast physical link can be required to perform an operation (e.g., HARQ, CSI, and channel measurement) associated with link adaptation for unicast and / or groupcast transmission performed on a physical layer.

[0158] Referring to Figure 6, the first UE 610 can connect a unicast session with the second UE 620. Also, the second UE 620 can connect a unicast session with the third UE 630. That is, a single UE can establish a unicast session with multiple UEs. Here, the second UE 620 needs to distinguish the unicast connection established with the first UE 610 from the unicast connection established with the third UE 630. Here, the second UE 620 can perform sidelink transmission with respect to the corresponding UE by identifying each unicast link. That is, the UE can identify each of the multiple unicast connections in the physical layer and then perform unicast transmission. That is, there can be multiple unicast and / or groupcast transmissions between UEs performing sidelink communication. Thus, as described above, an ID for identifying each connection can be required. Here, the ID for identifying each connection can use an ID in the upper layer, and can also use an ID in the physical layer based on an operation considering link adaptation. Here, for example, in the case of using an ID in the physical layer as an ID (e.g., destination ID) in the upper layer, a QoS requirement can not be satisfied or a collision can occur. Thus, a separate ID for the physical layer can be required. However, this is provided by way of example only and the disclosure is not limited thereto. Below, a method of determining a physical layer ID (SL layer-1 ID, ) based on the above description is described.

[0159] For example, the SL layer-1 ID can be used as a hopping ID value available in the physical layer for PSFCH transmission. Also, for example, the SL layer-1 ID can be used for another physical layer channel (e.g., PSSCH / PSCCH / PSBCH) and RS (e.g., SL CSI-RS, SL DMRS, SL PT-RS) transmission. Although the following description is made based on PSFCH transmission for clarity of description, this is provided by way of example only. That is, the SL layer-1 ID in the physical layer can be set without being limited to the above-described example.

[0160] Here, for example, the SL layer-1 ID can be a layer-1 link ID derived based on a layer-2 link ID value for identifying an upper layer session. For example, Figure 7 A method of deriving a layer-1 link ID based on unicast transmission is illustrated. Here, as described above, two UEs connecting a unicast session can share an ID with each other. Here, a layer-2 link ID can be generated through a combination of UE ID values shared between the two UEs through a unicast session connection process in the upper layer. In detail, referring to Figure 7 , the first UE 710 and the second UE 720 can connect a unicast session. Here, during a process of connecting a unicast session between the first UE 710 and the second UE 720, a layer-2 link ID can be generated based on an ID value of the first UE 710 and an ID value of the second UE 720 combination of the ID values of the first UE 810, the second UE 820, …, and the (K-1)th UE 830 to generate a layer-2 link ID value (b0, b1, b2, …, b X-1 Here, for example, the SL layer-1 ID as the physical layer ID can be generated using the least significant bits (LSB) T bits among the layer-2 link ID values generated with x bits as the layer-2 link ID. That is, the layer-1 link ID can be generated as b0, b1, b2, …, b T-1 . That is, the layer-1 link ID can be used as a partial value of the layer-2 link ID. Accordingly, X can be a value greater than T.

[0161] In addition, for example, the layer-1 link ID can be generated from the layer-2 link ID value based on another method. That is, the layer-1 link ID can be a value calculated based on the layer-2 link ID value. The LSB is provided only as an example.

[0162] In addition, for example, Figure 8 A method of deriving the layer-1 link ID based on the multicast transmission is illustrated. Here, in the case of the multicast session, a plurality of UEs can exist in a group, which is different from unicast. Here, the UEs in the group can share the ID. Here, the layer-2 link ID can be generated by the combination of the UE ID values shared between the UEs in the group through the multicast session connection procedure in the upper layer. In detail, referring to Figure 8 , the first UE 810, the second UE 820, …, the (K-1)th UE 830 can connect the multicast session as a single group. Here, during the process of connecting the multicast session including the UEs in the group, the layer-2 link ID value (b0, b1, b2, …, b the ID value of the second UE 820 … and the ID value of the (K-1)th UE 830 combination of the ID values of the first UE 810, the second UE 820, …, and the (K-1)th UE 830 to generate a layer-2 link ID value (b0, b1, b2, …, b X-1 That is, the layer-2 link ID value (b0, b1, b2, …, b X-1 Here, for example, in the case of performing the multicast transmission, it is necessary to perform reliable transmission within a limited coverage. Accordingly, all the UEs in the group can perform the multicast transmission in the same area. To this end, when generating the multicast link, the layer-2 link ID value can additionally consider the area ID value based on the base station configuration and the configuration between the UEs (e.g., PC5-RRC). The method of setting the layer-2 link ID value can be optionally enabled or disabled based on the configuration between the UEs or the base station configuration. The area ID value can be determined using the position value of the leader UE in the group or set as a value set for the group connection. Meanwhile, for example, in the case of Figure 8In this case, the operator "+" can indicate AND, XOR, or a combination operation of the ID bits.

[0163] Further, for example, a layer-2 link ID value associated with a groupcast transmission can be determined based on ID values of some UEs (or multiple UEs) in a group. For example, UEs included in a group can be flexibly changed. Thus, in a case where a layer-2 link ID value is generated based on ID values of all UEs, reliability of the layer-2 link ID value can be decreased due to flexibility in group members. By considering the above description, a layer-2 link ID value can be determined based on ID values of some UEs (or multiple UEs) in a group. For example, there can be a leader UE (or multiple leader UEs) in each group, and each group can perform an operation based on the leader UE. A layer-2 link ID value can be determined based on ID values of the leader UE (or multiple leader UEs) described in the foregoing. However, this is provided only as an example and the disclosure is not limited thereto.

[0164] Here, for example, an SL layer-1 ID as a physical layer ID can be generated using LSB T bits from a layer-2 link ID value having x bits, which are generated as a layer-2 link ID. That is, a layer-1 link ID can be generated as b0, b1, b2, …, b T-1 That is, a layer-1 link ID can be used as a partial value of a layer-2 link ID. Thus, in a case where a layer-2 link ID is generated based on a layer-1 link ID, a layer-2 link ID can be generated based on a layer-1 link ID and a value of a layer-2 link ID not included in the layer-1 link ID. Figure 8 In this case, X can be a value greater than T.

[0165] Further, for example, a layer-1 link ID can be generated from a layer-2 link ID value based on another method. That is, a layer-1 link ID can be a value calculated based on a layer-2 link ID value. LSB is provided only as an example.

[0166] Furthermore, for example, a Layer-1 link ID can be generated based on a combination of Layer-1 ID values ​​for each unicast and / or multicast. For example, a Layer-1 ID value may include at least one of a Layer-1 destination ID, a Layer-1 source ID, a HARQ process ID, a member ID in the aforementioned group, and a CRC bit of the associated PSCCH. Here, for example, the Layer-1 destination ID can be used to filter packets at the physical layer. That is, the UE can use the Layer-1 destination ID to verify whether a corresponding packet has been assigned to the UE. Furthermore, for example, a Layer-1 new ID can be a Layer-1 source ID, a HARQ process ID, or a group member ID. Here, it is provided only as an example, and this disclosure is not limited thereto. Here, a Layer-1 link ID can be generated by a combination of the aforementioned Layer-1 ID values. That is, a Layer-1 link ID refers to a Layer-1 ID representing a single unicast or multicast, and can be determined by a combination of the aforementioned Layer-1 ID values. Here, for example, a data Tx UE can indicate the destination Layer-1 ID, source Layer-1 ID, and HARQ process ID values ​​to a UE performing PSFCH transmission via the SCI format. As another example, at least one of the destination tier-1 ID, source tier-1 ID, and HARQ process ID values ​​can be shared between UEs during the session generation process. Furthermore, for example, at least one of the destination tier-1 ID, source tier-1 ID, and HARQ process ID values ​​can be shared between UEs in the corresponding session during the RRC connection generation process. Additionally, for example, the CRC bits of the relevant PSCCH can indicate that the CRC bits appended to the SCI format transmitted via the PSCCH are used as the tier-1 ID value for error correction and verification. As another example, the tier-1 ID value can also include a tier-1 area ID value. As another example, in the case of multicast, the tier-1 ID value can also include the aforementioned group member ID value. Here, the tier-1 link ID can be determined based on the combination of the aforementioned tier-1 ID values.

[0167] In detail, for example, the Layer-1 link ID could be here, For unicast, it can be Moreover, for multicast It can be here, It can be done as well as The values ​​are generated by combinations, as shown in Table 13 below. Here, in Table 13, the "+" operator can indicate the AND, XOR, or combination of these operations on the individual ID bits. That is, the "+" operator represents a combination operation, and this disclosure is not limited thereto.

[0168] In detail, It can be determined as one of the aforementioned Layer-1 ID values ​​(Alternative 1). Furthermore, for example, The combination of two layer-1 IDs from the aforementioned layer-1 ID values ​​can be used to determine (Alternative 2). Here, as described above, the combination of two layer-1 IDs can be performed using AND, OR, and XOR operations on the ID bits. Furthermore, for example, the combination of two layer-1 IDs can be performed using another operation. However, this is provided merely as an example and the present disclosure is not limited thereto. Moreover, for example, The combination of three layer-1 IDs from the aforementioned layer-1 ID values ​​can be used to determine (Alternative 3). Here, as described above, the combination of two layer-1 IDs can be performed using AND, OR, and XOR operations on the ID bits. Furthermore, for example, the combination of two layer-1 IDs can be performed using another operation. However, this is provided only as an example and the present disclosure is not limited thereto. As another example, This can be determined through RRC signaling. Here, RRC signaling can refer to the signaling used for RRC configuration between UEs, such as the aforementioned PC5-RRC signaling. Alternatively, it can be determined based on the SL ID value provided through the RRC signaling. Conversely, if no RRC configuration exists, the determination can be based on the aforementioned Alternative 1, Alternative 2, or Alternative 3. Here, for example, it can be determined that the UE is preset to respond to the absence of RRC configuration. The method is described. However, it is provided by way of example only and this disclosure is not limited thereto. Here, for example, as described above, Tables 14 and 15 below may relate to the determination of unicast. Methods ( Table 14) and the determination of multicast Methods ( (Table 15). Furthermore, for example, the Layer-1 Link ID value can be determined based on a combination of all Layer-1 ID values. That is, this disclosure is not limited to generating Layer-1 Link ID values ​​based on a combination of Tables 14 and 15.

[0169] As another example, determining unicast Methods and determination of multicast The methods can differ from one another. For example, since unicast transmission is performed between two UEs, it can be determined based on a combination of Layer-1 ID values. This has been described above using Alternative 1, Alternative 2, or Alternative 3. That is, a Layer-1 link ID determination method can be preset for the UE, and the UE can generate a Layer-1 link ID based on the preset method. Conversely, in the case of multicast transmission, multiple UEs can exist in a group. Here, the number of UEs included in each group can be different. Furthermore, the UE members included in the group can change flexibly. Considering this aspect, multicast can be set up or provided via RRC signaling similar to Alternative 4. That is, determine unicast. Methods and determination and use of multicast The methods can differ from one another.

[0170] [Table 13]

[0171]

[0172] [Table 14]

[0173]

[0174] [Table 15]

[0175]

[0176] Furthermore, for example, the UE can perform operations to meet QoS requirements using the SL-1 link ID value. Here, for example, refer to... Figure 9 The first UE 910 and the second UE 920 can establish a unicast session and perform sidelink communication. Here, the SL layer-1 link ID value used by the UE transmitting PSCCH / PSSCH (e.g., the first UE 910) can be generated based on the layer-1 destination ID. Furthermore, the SL layer-1 link ID for transmitting HARQ feedback (SFCI) used by the UE (e.g., the second UE 920) can be generated based on at least one of the layer-1 destination ID, source ID, group membership ID, and HARQ process ID values. That is, each of the first UE 910 and the second UE 920 establishing a unicast session can use a different SL layer-1 link ID. For example, each UE can use a different SL layer-1 link ID value based on the transmission information. Alternatively, for example, the first UE 910 and the second UE 920 can use the same SL layer-1 link ID value. However, this is provided by way of example only and the disclosure is not limited thereto. Furthermore, Figure 9 Only a single example of generating and applying SL-1 link ID values ​​is shown. That is, SL-1 link ID values ​​generated through other combinations can be used for different physical channels and RSs. However, this disclosure is not limited thereto.

[0177] Furthermore, for example, when a Layer-1 link ID for unicast and / or multicast transmission is provided via RRC signaling between base stations or UEs, or by an upper layer, the Layer-1 link ID can be determined based on the value provided by the RRC signaling or the upper layer. That is, if a new Layer-1 link ID value is set via PC5 RRC signaling, the set value can be used. Conversely, unless a new Layer-1 link ID value is set via PC5 RRC signaling, the Layer-1 link ID can be generated as described above.

[0179] As described above, the layer-1 link ID can be generated as a physical layer ID. For example, a method of applying a unicast layer-1 ID (hereinafter, L1 U-ID) value or a groupcast layer-1 ID (hereinafter, L1 G-ID) value to a PSFCH transmission is described below. Here, it is provided only as an example. A session link ID value can be used for another physical channel and signal. That is, the disclosure is not limited thereto. Hereinafter, a method for a feedback channel based on the above description.

[0180] For example, a PSFCH format based on a Zadoff-Chu (ZC) sequence can be considered. Here, the ZC sequence refers to an orthogonal sequence, and can be one of constant amplitude zero auto correlation (CAZAC) sequences. Here, the PSFCH format can be determined based on the ZC sequence. For example, the ZC sequence can be generated based on a single cyclic sequence α and its base sequence according to Equation 3 below.

[0181] [Equation 3]

[0182]

[0183] In Equation 3, for example, M ZC may be Here, m denotes a value corresponding to the number of resource blocks (RBs) to which each resource block is allocated a sequence, and for the PSFCH format, m can be δ = 0. In addition, a plurality of base sequences can be classified into a sequence group number u ∈ {0, 1, …, 29} and a base sequence number v in the corresponding group. Here, a single base sequence v = 0 can be set based on the ZC sequence length. In addition, for example, two base sequences v = 0 or 1 can be configured based on the ZC sequence length. In detail, considering the case where the PSFCH format is mapped to a small number of PRBs as a single PRB or two PRBs and is used to transmit information (e.g., ACK / NACK) therefrom, there is only a single base sequence (v = 0) in the sequence group. However, it is provided only as an example and the disclosure is not limited thereto. Here, if the sequence length is less than 36 (e.g., M ZC ∈ {6, 12, 18, 24}), the base sequence can be determined according to Equation 4 below.

[0184] [Equation 4]

[0185]

[0186] For example, in Equation 4, the value of v can be determined based on Table 16 below (e.g., sequence length M ZC = 12). For example, another sequence length can use the values shown in another table. However, it is provided only as an example and the disclosure is not limited thereto.

[0187] [Table 16]

[0188]

[0189] Hereinafter, a sequence group / sequence shift hopping and a cyclic shift (CS) hopping of a PSFCH format can be used based on the above description. For example, as described above, a PSFCH format provided on a sidelink can forward only 1-bit or 2-bit HARQ-ACK (or only NACK).

[0190] For example, a single PSFCH format can be used to forward SFCI based on a ZC sequence. Here, in order to generate a ZC sequence according to Equation 3 and Equation 4 described above, it can be necessary to determine a sequence group u and a sequence number v in a corresponding group. Subsequently, a CS value can be determined, and a final AC sequence can be generated. Here, referring to Table 16 above, a ZC sequence can have 30 base sequences. Accordingly, in the case of generating a single base sequence, it is necessary to select a sequence group number u for a base station. Here, for example, u can be determined based on the following Equation 5, and u can hop. Here, f gh may be a sequence group hopping pattern, and f ss may be a shift offset. That is, u can be changed (or hopped) based on a predetermined time or condition. Thereby, the above-described interference situation can be reduced.

[0191] [Equation 5]

[0192] u = (f gh +f ss ) mod 30

[0193] Here, referring to Figure 10 In NR V2X, at least one unicast and / or groupcast session connection can be generated between a plurality of UEs. That is, in a neighboring area, each UE can perform a plurality of unicast and / or groupcast session connections. Here, for example, as described above, a UE can perform sidelink data transmission on a determined physical resource. Here, the determined physical resource is selected based on a sensing operation for an Rx UE to determine a Tx UE, and a transmission operation can be performed. Here, for example, when there are a plurality of unicast and / or groupcast sessions between neighboring UEs, although a resource is selected, a "hidden node problem" or an invalid resource configuration (e.g., a wrong configured grant resource configuration) problem can occur. Here, independent AS parameters can be set for each unicast and / or groupcast session. Accordingly, many collisions can occur on a sidelink resource, and interference can occur based on an environment in which a neighboring UE is located.

[0194] In detail, unicast and / or groupcast session connection can be independently performed between UEs existing in out-of-coverage and in partial-coverage (e.g., UEs not under control of a base station). Thus, there can be potential collisions and interference between different unicast, groupcast, and broadcast transmissions generated among multiple UEs. In order to meet high QoS requirements by considering a sidelink communication environment, it is necessary to provide reliable link performance by maximizing the effect of interference randomization in PSFCH.

[0195] Thus, the sequence group hopping pattern f gh and the sequence shift f ss is performed according to Equation 5 above. For example, a parameter configuration regarding hopping for a single unicast or groupcast sidelink transmission and reception can be determined between UEs involved in a corresponding unicast or groupcast transmission. Here, information regarding whether to perform the above hopping can be exchanged through RRC signaling. In addition, for example, the information regarding whether to perform hopping can always be fixed, or can be determined based on different parameters. However, it is provided only as an example and the present disclosure is not limited thereto. In detail, for example, a case where the sequence group hopping is "enabled" at all times of PSFCH transmission can be considered. In contrast, sequence hopping (e.g., v=0) in the PSFCH sequence group can not be performed. That is, a parameter associated with the sequence group hopping can be fixed at least for PSFCH transmission. A detailed method can be represented by Equation 6 below.

[0196] [Equation 6]

[0197] v=0 or, f ss =n ID mod 30 v=0

[0198] Here, for example, if only a single PSFCH transmission is allowed for a single slot in NR V2X, a hopping method based on Equation 6 above can be applied. If it is always assumed that the value is 0, f gh can be used as an equation after Equation 6. Here, the shift offset value f ID may be changed by the above SL layer-1 ID or hopping ID n ss . Here, if the hopping ID is used, n may be replaced in Equation 6. Basically, n ID may be exchanged between UEs through a unicast / groupcast session connection procedure or a PC5-RRC connection reestablishment procedure. ID. Otherwise, The n ID value provided by the UE desiring to receive the PSFCH (e.g., the UE that previously performed the PSSCH data transmission) can be provided to the UE transmitting the PSFCH. In addition, the n ID value can be generated by the UE to have a larger number of bits or a combination of random bits (e.g., 8->16 bits) based on and other information, and can be provided to the corresponding UE and the UE associated with the unicast / groupcast session connection. For example, the n ID value having a length of 16 bits can be generated by adding a source ID (8 bits) and / or a UE member ID and a part or all of random bits having an additional 8-bit length or other layer-1 ID information bits, and can be provided to the associated UE. In this way, it is possible to provide an effect of randomizing interference between UEs belonging to different UE pairs. In addition, the number of bits of n ID is not limited to the above-described 16 bits, and can be greater than 8 bits. In the following sequence generation method, a method of replacing n with n ID can also be considered. Thus, a different offset value can be set for each ID. That is, a different u value can be generated. Here, with reference to Figure 11 , a case where the PSFCH transmission uses two OFDM symbols and a sequence group hopping is set for each OFDM symbol can be considered. Here, the n value in the first OFDM symbol can be 0, and the n value in the second OFDM symbol can be 1. That is, if the PSFCH format 0 is set to be transmitted using two OFDM symbols, the SFCI can be transmitted based on different base sequences for each symbol. Here, unless the transmission is performed based on the above-described description, the n value can always be 0. In this case, the PSFCH format 0 using two OFDM symbols can transmit the SFCI based on the same base sequence for each symbol.

[0199] As another example, if at least one PSFCH transmission is allowed for at least one slot in NR V2X, a hopping method based on the following Equation 7 can be applied. In detail, for example, if only a single HARQ-ACK transmission is allowed for a single slot, it can be difficult to meet the delay requirement in terms of ultra-reliable low latency communication (URLLC). Based on this, at least one PSFCH transmission can be considered in a single slot. For example, with reference to Figure 12HARQ-ACK of each of TB 1 and TB 2 can be transmitted in the first slot. That is, each of PSFCH 1 of TB 1 and PSFCH 2 of TB 1 can be transmitted in a single slot. Here, each of PSFCH 1 and PSFCH 2 can generate a different base sequence value. Thus, if a plurality of PSFCH transmissions of NR V2X communication is configured in a single slot, an OFDM symbol index l can be additionally considered. In this way, a base sequence can be generated based on a symbol unit, and a different base sequence can be used based on the symbol unit. Here, a different base sequence value can be generated for each PSFCH transmission in a slot.

[0200] [Equation 7]

[0201] v = 0

[0202] As another example, a parameter for a sequence group hopping method can be set based on RRC signaling. Here, if it is indicated that all sequence group hopping and sequence hopping are not performed, f gh v can be 0, as expressed in the following Equation 8. That is, neither group hopping nor sequence hopping can be performed.

[0203] [Equation 8]

[0204] f gh = 0

[0205] v = 0

[0206] On the contrary, if sequence group hopping is performed based on RRC signaling and sequence hopping is not performed, it can correspond to the above case in which sequence group hopping is "enabled" at all times.

[0207] Further, for example, for the above sequence hopping pattern, a random sequence c(i) for the sequence hopping pattern can be initialized based on the following Equation 9. Here, the random sequence c(i) can be initialized at the start of each DFN, or can be initialized in the PSFCH transmission start OFDM symbol. However, it is provided only as an example and the disclosure is not limited thereto.

[0208] [Equation 9]

[0209]

[0210] Meanwhile, c may be set by considering the above SL layer-1 ID init . Here, if a combination of many ID values is considered is set to have a large value, a larger number of sequence hopping patterns can be used in terms of sequence hopping. That is, if the number of sequence hopping patterns is determined by considering the combination of layer-1 ID values, the number of sequence hopping patterns can be increased. For example, by referring to Tables 13 to 15 above, the case where all of the 8-bit layer-1 ID values are used in the physical layer can be considered. Here, if the sequence hopping pattern is generated based on a single ID value, in combination with a large value, an interference randomization effect can be obtained. For example, by referring to Tables 13 to 15 above, the case where all of the 8-bit layer-1 ID values are used in the physical layer can be considered. Here, if the sequence hopping pattern is generated based on a single ID value, and , the eight sequence hopping patterns can be provided. In contrast, if the sequence hopping pattern is generated based on two ID values, , the 16 sequence hopping patterns can be provided. In detail, the hopping pattern sequence can be generated by a pseudo-random sequence c(i) based on Equation 9 above, and its random sequence can be initialized. Thus, as described above, the sequence hopping pattern can be changed by considering the combination of , the eight sequence hopping patterns can be provided. In contrast, if the sequence hopping pattern is generated based on two ID values, , the 16 sequence hopping patterns can be provided. In detail, the hopping pattern sequence can be generated by a pseudo-random sequence c(i) based on Equation 9 above, and its random sequence can be initialized. Thus, as described above, the sequence hopping pattern can be changed by considering the combination of , the eight sequence hopping patterns can be provided. In contrast, if the sequence hopping pattern is generated based on two ID values, , the 16 sequence hopping patterns can be provided. In detail, the hopping pattern sequence can be generated by a pseudo-random sequence c(i) based on Equation 9 above, and its random sequence can be initialized. Thus, as described above, the sequence hopping pattern can be changed by considering the combination of

[0211] As another example, if the sequence group hopping configuration of PSFCH is disabled, the sequence shift value and the sequence value in the group can be determined based on the aforementioned SL layer-1 ID value.

[0212] [Equation 8-1]

[0213] f gh = 0 f gh = 0 or

[0214] Regarding the above-described sequence hopping pattern, the random sequence c(i) for the sequence hopping pattern can be initialized based on Equation 9-1 below. Here, the random sequence c(i) can be initialized at the beginning of each DFN, or can be initialized in the PSFCH transmission start OFDM symbol. However, this is provided only as an example and the present disclosure is not limited thereto. The value of v may be applied in the same manner as described above. For example, The value of v may be always 0. If a different v value is used for each OFDM symbol, l' is used as the OFDM symbol index in the PSFCH transmission time slot.

[0215] [Equation 9-1]

[0216]

[0217] Further, for example, in case of performing groupcast transmission, the sequence hopping method for PSFCH transmission can be similarly applied to the above-described case of performing unicast transmission based on groupcast-based layer-1 link ID values. Here, for example may be and the SL layer-1 groupcast link ID values can be applied to have the same sequence hopping pattern and sequence shift offset value in a group.

[0218] As another example, even in case of having the same base sequence, interference effects can be minimized by applying different CS hopping. In detail, for example, as described above, the PSFCH format can forward SFCI based on a ZC sequence, and thus, a CS hopping operation as represented in the following Equation 10 can be performed.

[0219] [Equation 10]

[0220]

[0221] In Equation 10, denotes a DFN or a slot index in a sidelink radio frame, and l denotes an OFDM symbol number in PSFCH transmission. For example, the first symbol for PSFCH transmission can be l = 0, and the second symbol can be l = 1. Further, l' denotes an OFDM symbol index in a slot in which there is PSFCH transmission. Further, m0 denotes an initial CS value. Here, the CS value can be a starting offset value. For example, if the m0 value is set through the above-described PC5-RRC signaling, the set initial CS value m0 can be used. In contrast, unless the m0 value is set through the PC5-RRC signaling, m0 can be determined based on the following Equation 11.

[0222] [Equation 11]

[0223]

[0224] As another example, the aforementioned initial CS value m0 can be determined through a "PSFCH resource indicator" in SCI. That is, information indicating the initial CS value m0 can be transmitted using SCI included in PSCCH transmitted from a Tx UE. Here, an Rx UE can use information acquired from SCI for PSFCH transmission. In contrast, unless the initial CS value m0 is indicated through the "PSFCH resource indicator" in SCI, m0 can be determined according to Equation 11 described above.

[0225] As described above, different groups with independent multicast link ID values ​​can have independent CS start values ​​between groups, and PSFCH transmissions can be performed based on these start values. That is, using the above method, even when using the same base sequence, PSFCH transmissions can be performed on UEs that have previously performed group transmissions at the same point in time using different CS values.

[0226] Both of these methods can perform PSFCH transmissions for UEs that previously performed group transmissions at the same time point using the same base sequence in the group but different CS values. Here, as mentioned above, the m0 value can be provided from a specific UE or can be determined based on the multicast link ID value.

[0227] In addition, for example, m cs The value can vary depending on whether the HARQ-ACK value includes 1 bit or 2 bits, and can be represented by Table 17 or Table 18 below. Here, the HARQ-ACK value can be "0: ACK, 1: NACK". Furthermore, for example, in the case of sending only NACK, the HARQ-ACK value can be defined as "0: NACK, 1: DTX". However, this is provided only as an example and the disclosure is not limited thereto. In particular, in the case of sending only NACK, PSFCH transmission may not be performed for ACK. Instead, the data Tx UE expecting PSFCH reception does not know whether PSCCH was successfully received at the Rx UE. Therefore, as described above, retransmission can be determined by forwarding the DTX status to the data Tx UE. The value m in Table 17 or Table 18 below... cs Not limited to the values ​​listed therein. Any value of [0-11] can be used for HARQ-ACK values ​​(e.g., Table 17: (0 or 1), Table 18: ({0, 0}, {0, 1}, {1, 1}, {1, 0}).

[0228] [Table 17]

[0229] HARQ-ACK values 0 1 Sequence cyclic shift m cs = 0 m cs = 6

[0230] [Table 18]

[0231] HARQ-ACK values {0,0} {0,1} {1,1} {1,0} Sequence cyclic shift m cs = 0 m cs = 3 m cs = 6 m cs = 9

[0232] Furthermore, for example, if a different CS hopping method is determined for each OFDM symbol, then the function n, as represented by the following Equation 12, can be determined. cs (n c ,l). Here, it can be based on Use a random sequence to determine the function n cs (n c The above describes a method of determination. The method.

[0233] [Equation 12]

[0234]

[0235] The ZC sequence generated based on the above description can be mapped to a physical resource using one or two OFDM symbols according to Equation 13 below.

[0236] [Equation 13]

[0237]

[0238] As another example, a PSFCH format in which a modulation symbol is considered in addition to the above-described sequence-based PSFCH format can be considered. Here, the PSFCH format can be a format in which a modulation symbol is multiplied by a ZC sequence and then mapped to a physical resource. For example, if the number of SFCI bits is 1 bit or 2 bits (e.g., HARQ-ACK), a single modulation symbol d(0) can be generated by applying each of binary phase shift keying (BPSK) modulation and quadrature phase shift keying (QPSK) modulation. Here, the modulation symbol d(0) can be extended by multiplying the modulation symbol d(0) by the length of the ZC sequence obtained above. For example, Equation 14 below can represent a symbol y(n) having an extension value that is a sequence length corresponding to a single PRB.

[0239] [Equation 14]

[0240]

[0241] In addition, the symbol y(n) can be additionally multiplied by an orthogonal sequence w i (m) in a block-by-block form, which can be represented by Equation 15 below.

[0242] [Equation 15]

[0243]

[0244] Here, for example, in Equation 15, the orthogonal index value i of w i (m) can be set through PC5-RRC signaling. For example, if the orthogonal sequence index value i of w i (m) is set through PC5-RRC signaling, the set orthogonal sequence index value i can be used. In contrast, unless the orthogonal sequence index value i is set through PC5-RRC signaling, the orthogonal sequence index value i can be represented by Equation 16 below.

[0245] [Equation 16]

[0246] ​

[0247] As another example, in Equation 15, w i The orthogonal sequence index value i of (m) can be indicated by the "PSFCH resource indicator" of the SCI. That is, the data Tx UE can indicate a value to the Rx UE through the SCI included in the PSCCH. For example, if the orthogonal sequence index value i is indicated by the PSFCH resource indicator, the set orthogonal sequence index value i can be used. Conversely, unless the orthogonal sequence index value i is set by the PSFCH resource indicator, the orthogonal sequence index value i can be represented by the following Equation 16.

[0248] That is, if information regarding the selection of the CS value for the ZC sequence and the selection of the orthogonal sequence index value is provided from the Tx UE to the Rx UE via PSCCH, or if this information is preset via PC5-RRC signaling, then PSFCH transmission can be performed based on the indicated values.

[0249] Conversely, without prior signaling, it can be based on the physical layer ID value as defined above. The values ​​are used to select the CS value of the ZC sequence and the orthogonal sequence index value.

[0250] As another example, the PSFCH resource index can be based on It can be determined in different forms. Here, the PSFCH resource index can indicate the CS value of the ZC sequence and the orthogonal sequence index value. The mapping relationship between the PSFCH resource index, the CS value of the ZC sequence, and the orthogonal sequence index value can be preset via PC5-RRC signaling and can be indicated based on this mapping relationship. Meanwhile, for example, This can be the length of the orthogonal sequence. Here, referring to Table 20 below, we can determine this based on… The orthogonal sequence index values ​​are determined based on Equations 15 and 16 above.

[0251] In detail, in addition to the number of OFDM symbols allocated with demodulation synchronization signals (DMRS), it can be determined based on the number of OFDM symbols allocated with PSFCH (SCFI). And whether intra-slot transitions are set, the length of the orthogonal sequence is determined based on Tables 19 and 20 below. Here, This represents the total number of OFDM symbols assigned to RS and SFCI. For example, refer to... Figure 13 , The value is 4, and it can be set differently depending on whether a time-slot transition is set.

[0252] For example, refer to Figure 13 (a), unless an in-slot transition is set, Conversely, refer to Figure 13 (b) If an in-slot transition is configured, then For m′=0 and For m′=1. That is, different values ​​can be applied. In particular, if an intra-slot transition is performed, each of the preceding m′=0 and the following m′=1 in the slot can be multiplied by an orthogonal sequence. For details, see [reference needed]. Figure 13 (b) corresponds to The orthogonal sequence can be used for all m′ = 0 and m′ = 1. Here, by referring to Table 20 below, The value can be 0, and the final orthogonal sequence can be generated. Furthermore, for example, it can be considered whether to provide RRC signaling for the starting PRB of an intra-slot transition. Here, unless RRC signaling is provided for the starting PRB of an intra-slot transition, the starting PRB can be the lowest PRB index value allocated to the data channel. Here, the second transition of the subsequent ending PRB that performs the transition can correspond to the highest PRV index value allocated to the data channel. As another example, the indices of the starting and ending PRBs in the resource area allocated to the data channel can be determined by another method for different transitions based on the aforementioned SL ID values. However, this is provided only as an example and the present disclosure is not limited thereto.

[0253] [Table 19]

[0254]

[0255] [Table 20]

[0256]

[0257] Furthermore, for example, the PSFCH structure used to transmit feedback information based on the PSFCH format can be set based on the sidelink data channel structure. For example, the raw SFCI bits (e.g., in PSFCH format) can be scrambled after channel coding and rate matching. Here, in the case of single-layer transmission, q can be 0, and the encoded SCFI bits by can be on the PSFCH with a length of of To send. Here, the number of available resources (the number of resource elements (REs) and the modulation scheme) corresponding to a fixed number of PRBs can be determined. The size of the PRB used for PSFCH transmission can be preset based on the size of the original SCFI, or it can be set based on the RRC signaling. Furthermore, for example, the scrambling used for PSFCH can be determined based on Equation 17 below. Here, the scrambling sequence c can be generated based on a random sequence. (q)(i), and a corresponding initialization value can be represented by Equation 18 below. Here, for example, in Equation 18, The value can be an ID used in a physical layer as the SL ID value described above.

[0258] [Equation 17]

[0259]

[0260] [Equation 18]

[0261]

[0262] Further, for example, QPSK can be used for PSFCH modulation. Further, layer mapping and precoding can be transmitted based on a waveform (e.g., CP-OFDM or SC-FDMA) finally determined under the assumption of single layer and single antenna transmission.

[0263] Here, for example, the above-described various types of PSFCH formats can be preset to the UE. Further, for example, the various types of PSFCH formats can be provided between UEs associated with unicast / groupcast through PC5-RRC signaling. However, this is provided only as an example and the disclosure is not limited thereto. Here, for example, if the PSFCH resource configuration of a single NRV2X UE is set and determined based on PC5-RRC signaling in unicast or groupcast transmission, a part or all of the information included in Table 21 below can be provided through RRC signaling. However, this is provided only as an example and the disclosure is not limited thereto.

[0264] [Table 21]

[0265]

[0266] Figure 14 is a flowchart illustrating an example of a method of determining a physical layer session ID. Referring to Figure 14 At operation S1410, the UE can perform a unicast or groupcast session connection procedure. Here, as described above with reference to Figures 1 to 13As described above, two UEs can perform a session connection through a unicast session connection procedure. Furthermore, for example, multiple UEs can perform a multicast session connection based on a multicast session connection procedure. Here, as described above, in operation S1420, the UEs can exchange ID information during the session connection procedure. In operation S1430, the UEs can determine the physical layer ID representing the session established between the UEs based on the exchanged ID information. For example, the physical layer ID can be a layer-1 link ID derived based on the layer-2 link ID value used to identify the upper-layer session. Furthermore, for example, as described above, the layer-1 link ID can be generated based on a combination of layer-1 ID values ​​from each of the unicast and / or multicast sessions. For example, the layer-1 ID value may include at least one of a layer-1 destination ID, a layer-1 source ID, a HARQ process ID, and a CRC bit associated with the PSCCH.

[0267] Figure 15 This is a diagram illustrating an example of a base station device and a terminal device.

[0268] refer to Figure 15 The base station device 1500 may include a processor 1520, an antenna device 1512, a transceiver 1514, and a memory 1516.

[0269] Processor 1520 can perform baseband-related signal processing and may include upper-layer processing 1530 and physical layer processing 1540. Upper-layer processing 1530 can handle Media Access Control (MAC) layer, Radio Resource Control (RRC) layer, or other upper-layer operations. Physical layer processing 1540 can handle physical (PHY) layer operations (e.g., uplink receive signal processing and downlink transmit signal processing). In addition to performing baseband-related signal processing, processor 1520 can also control the overall operation of base station equipment 1500.

[0270] Antenna device 1512 may include at least one physical antenna. If antenna device 1512 includes multiple antennas, multiple-input multiple-output (MIMO) transmission and reception can be supported. Transceiver 1514 may include a radio frequency (RF) transmitter and an RF receiver. Memory 1516 may store operational processing information of processor 1520 and software, operating system (OS), applications, etc., associated with the operation of base station device 1500, and may include components such as buffers.

[0271] The processor 1520 of the base station device 1500 can be configured to implement the operation of the base station in the example disclosed herein.

[0272] Terminal device 1550 may include processor 1570, antenna device 1562, transceiver 1564, and memory 1566. Furthermore, communication between terminal devices may be performed based on sidelink communication, for example. That is, each terminal device 1550 performing sidelink communication refers not only to the base station device 1500 but also to devices that perform sidelink communication with other terminal devices 1550. However, this is provided only as an example.

[0273] Processor 1570 can perform baseband-related signal processing and may include upper-layer processing 1580 and physical layer processing 1590. Upper-layer processing 1580 can handle MAC layer, RRC layer, or other upper-layer operations. Physical layer processing 1590 can handle PHY layer operations (e.g., downlink receive signal processing and uplink transmit signal processing). In addition to performing baseband-related signal processing, processor 1570 can also control the overall operation of terminal device 1550.

[0274] Antenna device 1562 may include at least one physical antenna. If antenna device 1562 includes multiple antennas, MIMO transmission and reception can be supported. Transceiver 1564 may include an RF transmitter and an RF receiver. Memory 1566 may store operational processing information of processor 1570 and software, OS, applications, etc., associated with the operation of terminal device 1550, and may include components such as buffers.

[0275] The processor 1570 of the terminal device 1550 can be configured to implement the operation of the terminal in the example described herein.

[0276] Furthermore, for example, the processor 1570 of terminal device 1550 can perform sidelink communication with another terminal device. Here, for example, the processor 1570 of terminal device 1550 can establish a multicast and / or unicast session with another terminal device 1550. Furthermore, for example, the processor 1570 of terminal device 1550 can determine a physical layer session ID based on the established session. Furthermore, for example, the processor 1570 of terminal device 1550 can perform operations to meet QoS requirements based on the determined physical layer session ID, as described above.

[0277] The various examples described herein are intended to illustrate representative aspects of this disclosure, and not to describe all possible combinations and contents described in the various examples, which may be applied independently or by at least two of them.

[0278] Furthermore, the various examples of this disclosure can be implemented by hardware, firmware, software, or a combination thereof. In the case of hardware implementation, the examples can be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers, microprocessors, etc.

[0279] The scope of this disclosure includes software or machine-executable instructions (e.g., OS, application, firmware, program, etc.) that enable the operation of various example methods to be executed on a device or computer, and non-transitory computer-readable media that store such software or instructions for execution on a device or computer.

[0280] Industrial applicability

[0281] This disclosure applies to the process of determining a sidelink physical layer session ID in a wireless communication system, and to the process of sending feedback information by a user equipment (UE) in an NR V2X system.

Claims

1. A first wireless user equipment, comprising: At least one antenna configured to receive at least one wireless signal from at least one base station, wherein the at least one wireless signal is received via a downlink channel; At least one processor; and At least one memory storing instructions, which, when executed by the at least one processor, are configured to cause the first wireless user equipment to: Receive Radio Resource Control (RRC) signaling configuration indicating the sidelink (SL) identifier (ID) value; The layer 1 ID for SL communication is determined based on the least significant bit (LSB) portion of the layer 2 ID, where layer 1 is the physical layer of the wireless communication system and layer 2 is the layer above the physical layer. At least one data packet is received from the second wireless user equipment via the Physical Side Link Shared Channel (PSSCH) based on the Layer 1 ID; The following are used to generate orthogonal sequences for the Physical Side Link Feedback Channel (PSFCH) format: The SLID value; and Loop jump parameters; and Based on the orthogonal sequence, SL feedback information is sent to the second wireless user equipment via PSFCH.

2. The first wireless user equipment according to claim 1, wherein, The Layer 2 ID is used to identify at least one of the following: a unicast Layer 2 link; or a multicast Layer 2 link.

3. The first wireless user equipment according to claim 1, wherein, The Layer 2 ID includes at least one of the following: a Layer 2 source ID; or a Layer 2 destination ID, and The Layer 1 ID includes at least one of the following: Layer 1 source ID; or Layer 1 destination ID.

4. The first wireless user equipment according to claim 3, wherein, The instructions, when executed by the at least one processor, are configured to cause the first wireless user equipment to: Receive physical side link control channel (PSCCH) transmissions from the second wireless user equipment, the PSCCH transmissions indicating control information associated with the scheduling of the PSSCH; Receive side link control information (SCI) from the second wireless user equipment, wherein the SCI format indicates the layer 1 source ID and the layer 1 destination ID; as well as Based on receiving the at least one data packet via the PSSCH, at least one sidelink Hybrid Automatic Repeat Request (HARQ) feedback bit for PFSCH transmission is determined.

5. The first wireless user equipment according to claim 1, wherein, The initialization value Cinit used to generate the orthogonal sequence is determined based on the SL ID value.

6. The first wireless user equipment according to claim 1, wherein, The Layer 1 ID is used to filter packets at the physical layer of the first wireless user equipment, and The layer 1 ID consists of T bits, and the layer 2 ID consists of X bits, where X is greater than T.

7. The first wireless user equipment according to claim 1, wherein, The SL feedback information includes SL Hybrid Automatic Repeat Request (HARQ) feedback information associated with the PSSCH.

8. The first wireless user equipment according to claim 1, wherein, The orthogonal sequence is further generated based on the cyclic jump parameter, the group number of the sequence group of the orthogonal sequence, and the sequence number of the sequence group of the orthogonal sequence.

9. The first wireless user equipment according to claim 8, wherein, The group number of the sequence group of the orthogonal sequence is determined based on the SL ID value.

10. The first wireless user equipment according to claim 9, wherein, The group number of the sequence group is based on The SL ID value is determined by [the specific determination method], where the SL ID value is [the specific value]. as well as The sequence number within the sequence group is set to zero.

11. The first wireless user equipment according to claim 1, wherein, The cyclic transition parameter is determined based on a value determined according to the multicast link ID.

12. The first wireless user equipment according to claim 11, wherein, The Layer 1 ID includes at least one of the following: Layer 1 source ID; or Layer 1 destination ID, and The multicast link ID is based on at least one of the following: The Layer 1 source ID; or The ID of each member in the group.

13. A first wireless user equipment, comprising: At least one antenna configured to receive at least one wireless signal from at least one base station, wherein the at least one wireless signal is received via a downlink channel; At least one processor; and At least one memory storing instructions, which, when executed by the at least one processor, are configured to cause the first wireless user equipment to: Receive a Radio Resource Control (RRC) message indicating a sidelink (SL) identifier (ID) value, wherein layer-1 is the physical layer of the wireless communication system, and wherein layer-2 is the upper layer of the physical layer; The layer 1 source ID is determined based on the least significant bit (LSB) portion of the layer 2 source ID; The Layer 1 destination ID is determined based on the least significant bit (LSB) portion of the Layer 2 destination ID; At least one data packet is received from the second wireless user equipment via the Physical Side Link Shared Channel (PSSCH) based on the Layer 1 destination ID; The following are used to generate orthogonal sequences for the Physical Side Link Feedback Channel (PSFCH) format: The SL ID value; and The Layer 1 source ID; and Based on the orthogonal sequence, SL feedback information is sent to the second wireless user equipment via PSFCH.

14. The first wireless user equipment according to claim 13, wherein, The orthogonal sequence is further generated based on the cyclic jump parameter, the group number of the sequence group of the orthogonal sequence, and the sequence number of the sequence group of the orthogonal sequence.

15. The first wireless user equipment according to claim 14, wherein, The group number of the sequence group is based on The SL ID value is determined by [the specific determination method], where the SL ID value is [the specific value]. as well as The sequence number within the sequence group is set to zero.

16. The first wireless user equipment according to claim 14, wherein, The cyclic transition parameter α is determined based on the value determined according to the Layer 1 source ID.

17. The first wireless user equipment according to claim 13, wherein, The instructions, when executed by the at least one processor, are configured to cause the first wireless user equipment to: Receive physical side link control channel (PSCCH) transmissions from the second wireless user equipment, the PSCCH transmissions indicating control information associated with the scheduling of the PSSCH; Receive side link control information (SCI) from the second wireless user equipment, wherein the SCI format indicates the layer 1 source ID and the layer 1 destination ID; as well as Based on receiving the at least one data packet via the PSSCH, at least one sidelink Hybrid Automatic Repeat Request (HARQ) feedback bit for PFSCH transmission is determined.

18. The first wireless user equipment according to claim 13, wherein, The initialization value Cinit of the orthogonal sequence is determined based on the SL ID value.

19. The first wireless user equipment according to claim 13, wherein, The SL feedback information includes SL Hybrid Automatic Repeat Request (HARQ) feedback information associated with the at least one data packet sent via the PSSCH.

20. The first wireless user equipment according to claim 13, wherein, The sequence group number of the orthogonal sequence is determined based on the SL ID value.

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