Method and apparatus for selecting synchronization reference in NR V2X

Abstract

Provided are a method by which a first device performs wireless communication and a device supporting the method. The method may include the following steps: receiving information related to a sidelink (SL) bandwidth part (BWP); receiving SL synchronization priority order information set by a global navigation satellite system (GNSS)-based synchronization from a network; receiving information from the network indicating whether to deactivate a base station (BS)-related synchronization reference; based on the information indicating the deactivation of the base station-related synchronization reference, detecting a synchronization signal sent by a GNSS-related synchronization reference or another UE through the SL BWP; and performing synchronization with respect to the GNSS-related synchronization reference or a synchronization reference from one of the other UEs based on the synchronization signal.

Description

Technical Field

[0001] The present disclosure relates to wireless communication systems. Background Art

[0002] Sidelink (SL) communication is a communication scheme in which a direct link is established between user equipments (UEs) and the UEs exchange voice and data directly with each other without intervention of an evolved Node B (eNB). SL communication is being considered as a solution to eNB overhead caused by the rapid growth of data traffic.

[0003] V2X (Vehicle-to-Everything) refers to the communication technology used by vehicles to exchange information with other vehicles, pedestrians, and infrastructure-equipped objects. V2X can be categorized into four types: V2V (Vehicle-to-Vehicle), V2I (Vehicle-to-Infrastructure), V2N (Vehicle-to-Network), and V2P (Vehicle-to-Pedestrian). V2X communication can be provided via the PC5 interface and / or the Uu interface.

[0004] In addition, as more and more communication devices require larger communication capacity, there is a need for enhanced mobile broadband communication compared to traditional radio access technologies (RATs). Therefore, the design of communication systems that take into account UEs or services that are sensitive to reliability and latency has also been discussed, and the next generation of radio access technologies that take into account enhanced mobile broadband communication, massive machine-to-machine communication (MTC), and ultra-reliable low-latency communication (URLLC) can be referred to as new RATs (radio access technologies) or NRs (new radios).

[0005] Figure 1 This diagram describes NR-based V2X communication compared to V2X communication based on RATs used before NR. Figure 1 The embodiments of the present disclosure may be combined with various embodiments of the present disclosure.

[0006] Regarding V2X communication, when discussing RATs used prior to NR, the focus is on solutions that provide safety services based on V2X messages such as BSM (Basic Safety Message), CAM (Cooperation Awareness Message), and DENM (Decentralized Environment Notification Message). V2X messages may include location information, dynamic information, attribute information, etc. For example, a UE may send a periodic CAM message type and / or an event-triggered DENM message type to another UE.

[0007] For example, a CAM can include dynamic vehicle status information such as direction and speed, static vehicle data such as size, and basic vehicle information such as exterior lighting status and route details. For example, a UE can broadcast a CAM, and the latency of the CAM can be less than 100ms. For example, a UE can generate a DENM and transmit it to another UE in unexpected situations such as vehicle breakdown or an accident. For example, all vehicles within the UE's transmission range can receive the CAM and / or DENM. In this case, the DENM can take precedence over the CAM.

[0008] Since then, various V2X scenarios have been proposed for NR regarding V2X communications, including vehicle platooning, advanced driving, extended sensors, and remote driving.

[0009] For example, based on vehicle platooning, vehicles can be dynamically formed into groups to move together. For example, to perform platooning operations based on vehicle formation, vehicles in the group can receive periodic data from the lead vehicle. For example, vehicles in the group can use the periodic data to reduce or increase the spacing between vehicles.

[0010] For example, based on advanced driving, vehicles can be semi-autonomous or fully autonomous. For example, each vehicle can adjust its trajectory or maneuver based on data obtained from local sensors of nearby vehicles and / or nearby logical entities. In addition, for example, each vehicle can share driving intentions with nearby vehicles.

[0011] For example, based on the extended sensors, raw data, processed data, or real-time video data obtained through local sensors can be exchanged between vehicles, logical entities, pedestrian UEs, and / or V2X application servers. This allows the vehicle to recognize a further improved environment compared to the environment detected using its own sensors, for example.

[0012] For example, remote driving can enable a person or remote vehicle in a dangerous environment to operate or control a remote vehicle, using a remote driver or V2X application. For example, if the route is predictable (e.g., public transportation), cloud-based driving can be used to operate or control the remote vehicle. Furthermore, remote driving can be achieved by accessing a cloud-based backend service platform.

[0013] Meanwhile, schemes for specifying service requirements for various V2X scenarios such as vehicle platooning, advanced driving, extended sensors, remote driving, etc. are discussed in NR-based V2X communications. Summary of the Invention

[0014] Technical issues

[0015] At the same time, the UE needs to obtain synchronization from a synchronization reference in order to perform SL communication. For example, the synchronization reference can be at least one of a global navigation satellite system (GNSS), a base station, a UE directly synchronized with the GNSS, a UE indirectly synchronized with the GNSS, a UE directly synchronized with the base station, a UE indirectly synchronized with the base station, and / or remaining UEs. For example, during the synchronization process, the base station or the GNSS can be set as the highest priority. In this case, it is necessary to provide a method for the UE to select a synchronization reference and an apparatus supporting the method.

[0016] Technical Solution

[0017] In one embodiment, a method for performing wireless communication by a first device is provided. The method may include: receiving information related to a sidelink (SL) bandwidth part (BWP); receiving SL synchronization priority order information set to synchronization based on a global navigation satellite system (GNSS) from a network; receiving information indicating whether to deactivate selection of a base station (BS)-related synchronization reference from the network; detecting a synchronization signal sent by a GNSS-related synchronization reference or other UE through the SL BWP based on the information indicating deactivation of selection of the BS-related synchronization reference; and performing synchronization with a GNSS-related synchronization reference or one of the other UEs based on the synchronization signal, wherein the synchronization reference related to GNSS-based synchronization includes GNSS, GNSS-related synchronization reference, BS-related synchronization reference, and other UEs, wherein the GNSS-related synchronization reference includes UEs directly synchronized with the GNSS and UEs indirectly synchronized with the GNSS, and wherein the BS-related synchronization reference includes a BS, a UE directly synchronized with the BS, and a UE indirectly synchronized with the BS.

[0018] Beneficial effects

[0019] A user equipment (UE) can efficiently perform SL communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This diagram describes NR-based V2X communication compared to V2X communication based on RATs used before NR.

[0021] Figure 2 A communication system 1 according to an embodiment of the present disclosure is shown.

[0022] Figure 3 A wireless device according to an embodiment of the present disclosure is shown.

[0023] Figure 4 A signal processing circuit for transmitting a signal according to an embodiment of the present disclosure is shown.

[0024] Figure 5Another example of a wireless device according to an embodiment of the present disclosure is shown.

[0025] Figure 6 A handheld device according to an embodiment of the present disclosure is shown.

[0026] Figure 7 A vehicle or autonomous vehicle according to an embodiment of the present disclosure is shown.

[0027] Figure 8 The structure of the NR system according to an embodiment of the present disclosure is shown.

[0028] Figure 9 The functional division between NG-RAN and 5GC according to an embodiment of the present disclosure is shown.

[0029] Figure 10 A radio protocol architecture according to an embodiment of the present disclosure is shown.

[0030] Figure 11 The structure of the NR system according to an embodiment of the present disclosure is shown.

[0031] Figure 12 The structure of the time slot of the NR frame according to an embodiment of the present disclosure is shown.

[0032] Figure 13 An example of a BWP according to an embodiment of the present disclosure is shown.

[0033] Figure 14 A radio protocol architecture for SL communication according to an embodiment of the present disclosure is shown.

[0034] Figure 15 A UE performing V2X or SL communication according to an embodiment of the present disclosure is shown.

[0035] Figure 16 A process of performing V2X or SL communication by a UE based on a transmission mode according to an embodiment of the present disclosure is shown.

[0036] Figure 17 Three playback types according to an embodiment of the present disclosure are shown.

[0037] Figure 18 FIG2 shows a synchronization source or synchronization reference of V2X according to an embodiment of the present disclosure.

[0038] Figure 19 A process for UE to perform synchronization according to an embodiment of the present disclosure is shown.

[0039] Figure 20 A method for performing synchronization by a first device according to an embodiment of the present disclosure is shown.

[0040] Figure 21 A method for performing synchronization by a second device according to an embodiment of the present disclosure is shown.

[0041] Figure 22 A method for a first device to perform wireless communication according to an embodiment of the present disclosure is shown.

[0042] Figure 23 A method for a first device to perform wireless communication according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0043] In this specification, "A or B" may mean "only A", "only B", or "both A and B". In other words, in this specification, "A or B" may be interpreted as "A and / or B". For example, in this specification, "A, B or C" may mean "only A", "only B", "only C", or "any combination of A, B, and C".

[0044] As used in this specification, a slash ( / ) or a comma may mean "and / or". For example, "A / B" may mean "A and / or B". Thus, "A / B" may mean "only A", "only B", or "both A and B". For example, "A, B, C" may mean "A, B, or C".

[0045] In this specification, “at least one of A and B” may mean “only A”, “only B”, or “both A and B”. In addition, in this specification, the expression “at least one of A or B” or “at least one of A and / or B” may be interpreted as “at least one of A and B”.

[0046] In addition, in this specification, “at least one of A, B, and C” may mean “only A,” “only B,” “only C,” or “any combination of A, B, and C.” In addition, “at least one of A, B, or C” or “at least one of A, B, and / or C” may mean “at least one of A, B, and C.”

[0047] In addition, the brackets used in this specification may mean "for example". Specifically, when it is indicated as "control information (PDCCH)", this may mean that "PDCCH" is proposed as an example of "control information". In other words, the "control information" of this specification is not limited to "PDCCH", and "PDDCH" may be proposed as an example of "control information". Specifically, when it is indicated as "control information (i.e., PDCCH)", this may also mean that "PDCCH" is proposed as an example of "control information".

[0048] The technical features described in each of the drawings in this specification may be implemented separately or simultaneously.

[0049] The techniques described below can be used in various wireless communication systems such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), etc. CDMA can be implemented using radio technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA-2000. TDMA can be implemented using radio technologies such as Global System for Mobile Communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rates for GSM Evolution (EDGE). OFDMA can be implemented using radio technologies such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Evolved UTRA (E-UTRA), etc. IEEE 802.16m is an evolved version of IEEE 802.16e and provides backward compatibility for systems based on IEEE 802.16e. UTRA is part of the Universal Mobile Telecommunications System (UMTS). 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is part of Evolved UMTS (E-UMTS) that uses E-UTRA. 3GPP LTE uses OFDMA in the downlink and SC-FDMA in the uplink. LTE-Advanced (LTE-A) is an evolution of LTE.

[0050] 5G NR is a successor technology to LTE-A, a new mobile communication system with high performance, low latency, and high availability. 5G NR can use all available spectrum resources, including low-frequency bands below 1 GHz, intermediate frequency bands from 1 GHz to 10 GHz, and high-frequency bands (millimeter waves) above 24 GHz.

[0051] For clarity of description, the following description will mainly focus on LTE-A or 5G NR. However, the technical features of the embodiments of the present disclosure are not limited thereto.

[0052] Hereinafter, devices to which various embodiments of the present disclosure can be applied will be described.

[0053] The various descriptions, functions, processes, proposals, methods and / or operational flows of the present disclosure described in this document may be applied to, but not limited to, various fields requiring wireless communication / connection (e.g., 5G) between devices.

[0054] Hereinafter, a more detailed description will be given with reference to the accompanying drawings. In the following drawings / descriptions, unless otherwise described, the same reference numerals may represent the same or corresponding hardware blocks, software blocks or functional blocks.

[0055] Figure 2A communication system (1) according to an embodiment of the present disclosure is shown.

[0056] refer to Figure 2 , a communication system (1) to which various embodiments of the present disclosure are applied includes a wireless device, a base station (BS), and a network. Herein, a wireless device refers to a device that performs communication using a radio access technology (RAT) (e.g., 5G New RAT (NR) or Long Term Evolution (LTE)) and may be referred to as a communication / radio / 5G device. The wireless device may include, but is not limited to, a robot (100a), a vehicle (100b-1, 100b-2), an extended reality (XR) device (100c), a handheld device (100d), a home appliance (100e), an Internet of Things (IoT) device (100f), and an artificial intelligence (AI) device / server (400). For example, a vehicle may include a vehicle with a wireless communication function, an autonomous vehicle, and a vehicle capable of performing inter-vehicle communication. Herein, a vehicle may include an unmanned aerial vehicle (UAV) (e.g., a drone). XR devices may include augmented reality (AR) / virtual reality (VR) / mixed reality (MR) devices and may be implemented in the form of head-mounted devices (HMDs), head-up displays (HUDs) installed in vehicles, televisions, smartphones, computers, wearable devices, home appliances, digital signage, vehicles, robots, etc. Handheld devices may include smartphones, smart boards, wearable devices (e.g., smart watches or smart glasses), and computers (e.g., notebooks). Home appliances may include TVs, refrigerators, and washing machines. IoT devices may include sensors and smart meters. For example, a BS and a network may be implemented as wireless devices, and a specific wireless device (200a) may operate as a BS / network node relative to other wireless devices.

[0057] Here, the wireless communication technology implemented in the wireless devices 100a to 100f of the present disclosure may include narrowband IoT for low-power communication in addition to LTE, NR, and 6G. In this case, for example, NB-IoT technology may be an example of low-power wide area network (LPWAN) technology and may be implemented as standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the names described above. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 100a to 100f of the present disclosure may perform communication based on LTE-M technology. In this case, as an example, LTE-M technology may be an example of LPWAN and may be referred to by various names including enhanced machine type communication (eMTC). For example, LTE-M technology may be implemented as at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-bandwidth limited (non-BL), 5) LTE-MTC, 6) LTE machine type communication, and / or 7) LTE M, and is not limited to the names described above. Additionally or alternatively, considering low-power communication, the wireless communication technology implemented in the wireless devices 100a to 100f of the present disclosure may include at least one of Bluetooth, a low-power wide area network (LPWAN), and ZigBee, and is not limited to the above names. As an example, ZigBee technology can generate a personal area network (PAN) related to low / low-power digital communication based on various standards including IEEE 802.15.4, and can be called by various names.

[0058] Wireless devices 100a to 100f can connect to a network 300 via a base station (BS) 200. AI technology can be applied to wireless devices 100a to 100f, and wireless devices 100a to 100f can connect to an AI server 400 via the network 300. The network 300 can be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. While wireless devices 100a to 100f can communicate with each other via the BS 200 / network 300, wireless devices 100a to 100f can also communicate directly with each other (e.g., sidelink communication) without going through the BS / network. For example, vehicles 100b-1 and 100b-2 can communicate directly (e.g., vehicle-to-vehicle (V2V) / vehicle-to-everything (V2X) communication). IoT devices (e.g., sensors) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

[0059] Wireless communication / connection 150a, 150b, or 150c may be established between wireless devices 100a to 100f / BS 200 or BS 200 / BS 200. Here, the wireless communication / connection may be established via various RATs (e.g., 5G NR), such as uplink / downlink communication 150a, sidelink communication 150b (or D2D communication), or inter-BS communication (e.g., relay, integrated access backhaul (IAB)). The wireless device and the BS / wireless device may transmit / receive radio signals to / from each other via the wireless communication / connections 150a and 150b. For example, the wireless communication / connections 150a and 150b may transmit / receive signals via various physical channels. To this end, various configuration information configuration processes, various signal processing processes (e.g., channel coding / decoding, modulation / demodulation, and resource mapping / demapping), and at least a portion of the resource allocation process for transmitting / receiving radio signals may be performed based on various proposals of the present disclosure.

[0060] Figure 3 A wireless device according to an embodiment of the present disclosure is shown.

[0061] refer to Figure 3 , the first wireless device (100) and the second wireless device (200) can transmit radio signals via various RATs (e.g., LTE and NR). Herein, {the first wireless device (100) and the second wireless device (200)} may correspond to Figure 2 {wireless device (100x) and BS (200)} and / or {wireless device (100x) and wireless device (100x)}.

[0062] The first wireless device 100 may include one or more processors 102 and one or more memories 104, and may additionally further include one or more transceivers 106 and / or one or more antennas 108. The processor(s) 102 may control the memory(s) 104 and / or the transceiver(s) 106, and may be configured to implement the descriptions, functions, processes, proposals, methods, and / or operational flows disclosed herein. For example, the processor(s) 102 may process information in the memory(s) 104 to generate first information / signals, and then transmit a radio signal including the first information / signals through the transceiver(s) 106. The processor(s) 102 may receive a radio signal including second information / signals through the transceiver 106, and then store information obtained by processing the second information / signals in the memory(s) 104. The memory(s) 104 may be connected to the processor(s) 102 and may store various information related to the operation of the processor(s) 102. For example, the memory(s) 104 may store software code including instructions for executing part or all of the processing controlled by the processor(s) 102 or for performing the descriptions, functions, procedures, proposals, methods, and / or operational flows disclosed in this document. Here, the processor(s) 102 and the memory(s) 104 may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver(s) 106 may be connected to the processor(s) 102 and transmit and / or receive radio signals via the antenna(s) 108. Each transceiver 106 may include a transmitter and / or a receiver. The transceiver(s) 106 may be used interchangeably with the radio frequency (RF) unit(s). In the present disclosure, a wireless device may represent a communication modem / circuit / chip.

[0063] The second wireless device 200 may include one or more processors 202 and one or more memories 204, and may additionally further include one or more transceivers 206 and / or one or more antennas 208. The processor(s) 202 may control the memory(s) 204 and / or the transceiver(s) 206, and may be configured to implement the descriptions, functions, processes, proposals, methods, and / or operational flows disclosed herein. For example, the processor(s) 202 may process information in the memory(s) 204 to generate third information / signals, and then transmit a radio signal including the third information / signals through the transceiver(s) 206. The processor(s) 202 may receive a radio signal including fourth information / signals through the transceiver(s) 106, and then store information obtained by processing the fourth information / signals in the memory(s) 204. The memory(s) 204 may be connected to the processor(s) 202 and may store various information related to the operation of the processor(s) 202. For example, the memory(s) 204 may store software code including instructions for executing part or all of the processing controlled by the processor(s) 202 or for executing the descriptions, functions, procedures, proposals, methods, and / or operational flows disclosed in this document. Here, the processor(s) 202 and the memory(s) 204 may be part of a communication modem / circuitry / chip designed to implement a RAT (e.g., LTE or NR). The transceiver(s) 206 may be connected to the processor(s) 202 and transmit and / or receive radio signals via the antenna(s) 208. Each transceiver 206 may include a transmitter and / or a receiver. The transceiver(s) 206 may be used interchangeably with the RF unit(s). In the present disclosure, a wireless device may represent a communication modem / circuitry / chip.

[0064] The hardware elements of wireless devices 100 and 200 will be described in more detail below. One or more protocol layers may be, but are not limited to, implemented by one or more processors 102 and 202. For example, one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, and SDAP). One or more processors 102 and 202 may generate one or more protocol data units (PDUs) and / or one or more service data units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operational flows disclosed herein. One or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operational flows disclosed herein. One or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operational flows disclosed herein, and provide the generated signals to one or more transceivers 106 and 206. One or more processors 102 and 202 can receive signals (e.g., baseband signals) from one or more transceivers 106 and 206 and obtain PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, processes, proposals, methods, and / or operational flows disclosed in this document.

[0065] The one or more processors 102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or more processors 102 and 202 may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more application-specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field-programmable gate arrays (FPGAs) may be included in the one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flows disclosed in this document may be implemented using firmware or software, and the firmware or software may be configured to include modules, processes, or functions. The firmware or software configured to execute the descriptions, functions, processes, proposals, methods, and / or operational flows disclosed in this document may be included in the one or more processors 102 and 202 or stored in one or more memories 104 and 204, thereby being driven by the one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flows disclosed in this document may be implemented using software or firmware in the form of code, commands, and / or command sets.

[0066] One or more memories 104 and 204 can be connected to one or more processors 102 and 202 and can store various types of data, signals, messages, information, programs, codes, instructions, and / or commands. One or more memories 104 and 204 can be composed of read-only memory (ROM), random access memory (RAM), electrically erasable programmable read-only memory (EPROM), flash memory, hard drive, registers, cash memory, computer-readable storage media, and / or combinations thereof. One or more memories 104 and 204 can be located internally and / or externally to one or more processors 102 and 202. One or more memories 104 and 204 can be connected to one or more processors 102 and 202 via various technologies such as wired or wireless connections.

[0067] One or more transceivers 106 and 206 may transmit user data, control information, and / or radio signals / channels described in the methods and / or operational flows of this document to one or more other devices. One or more transceivers 106 and 206 may receive user data, control information, and / or radio signals / channels described in the descriptions, functions, processes, proposals, methods, and / or operational flows disclosed in this document from one or more other devices. For example, one or more transceivers 106 and 206 may be connected to one or more processors 102 and 202 and may transmit and receive radio signals. For example, one or more processors 102 and 202 may control the one or more transceivers 106 and 206 to transmit user data, control information, or radio signals to one or more other devices. One or more processors 102 and 202 may control the one or more transceivers 106 and 206 to receive user data, control information, or radio signals from one or more other devices. One or more transceivers 106 and 206 can be connected to one or more antennas 108 and 208, and one or more transceivers 106 and 206 can be configured to transmit and receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, processes, proposals, methods, and / or operational flows disclosed in this document via one or more antennas 108 and 208. In this document, one or more antennas can be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106 and 206 can convert received radio signals / channels, etc. from RF band signals to baseband signals so that the received user data, control information, radio signals / channels, etc. can be processed by one or more processors 102 and 202. One or more transceivers 106 and 206 can convert the user data, control information, radio signals / channels, etc. processed by one or more processors 102 and 202 from baseband signals to RF band signals. To this end, one or more transceivers 106 and 206 can include (analog) oscillators and / or filters.

[0068] Figure 4 A signal processing circuit for transmitting a signal according to an embodiment of the present disclosure is shown.

[0069] refer to Figure 4 , the signal processing circuit (1000) may include a scrambler (1010), a modulator (1020), a layer mapper (1030), a precoder (1040), a resource mapper (1050) and a signal generator (1060). Figure 4 operations / functions, not limited to Figure 3 The processor (102, 202) and / or transceiver (106, 206) of Figure 3processor (102, 202) and / or transceiver (106, 206) to implement Figure 4 For example, you can Figure 3 The processor (102, 202) implements blocks 1010 to 1060. Alternatively, the Figure 3 The processor (102, 202) implements blocks 1010 to 1050 and can be implemented by Figure 3 The transceiver (106, 206) is used to implement block 1060.

[0070] Can be passed Figure 4 The signal processing circuit (1000) converts the codeword into a radio signal. In this article, the codeword is a coded bit sequence of an information block. The information block may include a transport block (e.g., UL-SCH transport block, DL-SCH transport block). The radio signal may be transmitted via various physical channels (e.g., PUSCH and PDSCH).

[0071] Specifically, the codeword can be converted into a scrambled bit sequence by the scrambler 1010. The scrambling sequence for scrambling can be generated based on an initial value, and the initial value can include the ID information of the wireless device. The scrambled bit sequence can be modulated into a modulation symbol sequence by the modulator 1020. The modulation scheme may include pi / 2-binary phase shift keying (pi / 2-BPSK), m-phase shift keying (m-PSK), and m-quadrature amplitude modulation (m-QAM). The complex modulation symbol sequence can be mapped to one or more transmission layers by the layer mapper 1030. The modulation symbol of each transmission layer can be mapped (precoded) to (one or more) corresponding antenna ports by the precoder 1040. The output z of the precoder 1040 can be obtained by multiplying the output y of the layer mapper 1030 with the N*M precoding matrix W. Here, N is the number of antenna ports and M is the number of transmission layers. The precoder 1040 can perform precoding after performing transform precoding (e.g., DFT) on the complex modulation symbols. Alternatively, the precoder 1040 may perform precoding without performing transform precoding.

[0072] The resource mapper 1050 can map the modulation symbols of each antenna port to time-frequency resources. The time-frequency resources may include multiple symbols in the time domain (e.g., CP-OFDMA symbols and DFT-s-OFDMA symbols) and multiple subcarriers in the frequency domain. The signal generator 1060 can generate a radio signal from the mapped modulation symbols, and the generated radio signal can be sent to other devices through each antenna. To this end, the signal generator 1060 may include an inverse fast Fourier transform (IFFT) module, a cyclic prefix (CP) inserter, a digital-to-analog converter (DAC), and an upconverter.

[0073] Can be used with Figure 4 The signal processing process for the signal received in the wireless device is configured in the opposite manner to the signal processing process (1010-1060) of the wireless device. Figure 3 100, 200) can receive a radio signal from the outside through an antenna port / transceiver. The received radio signal can be converted into a baseband signal by a signal restorer. To this end, the signal restorer may include a frequency downlink converter, an analog-to-digital converter (ADC), a CP remover, and a fast Fourier transform (FFT) module. Next, the baseband signal can be restored to a codeword through a resource demapping process, a post-coding process, a demodulation processor, and a descrambling process. The codeword can be restored to the original information block by decoding. Therefore, a signal processing circuit (not shown) for receiving a signal may include a signal restorer, a resource demapper, a post-coding process, a demodulator, a descrambler, and a decoder.

[0074] Figure 5 Another example of a wireless device according to an embodiment of the present disclosure is shown. The wireless device can be implemented in various forms according to use cases / services (refer to Figure 2 ).

[0075] refer to Figure 5 , the wireless device (100, 200) may correspond to Figure 3 The wireless devices (100, 200) may be configured by various elements, components, units / portions and / or modules. For example, each of the wireless devices (100, 200) may include a communication unit (110), a control unit (120), a storage unit (130) and additional components (140). The communication unit may include a communication circuit (112) and (one or more) transceivers (114). For example, the communication circuit (112) may include Figure 3 One or more processors (102, 202) and / or one or more memories (104, 204). For example, the transceiver(s) (114) may include Figure 3The wireless device includes one or more transceivers (106, 206) and / or one or more antennas (108, 208). The control unit (120) is electrically connected to the communication unit (110), the memory (130), and the additional components (140), and controls the overall operation of the wireless device. For example, the control unit (120) can control the electrical / mechanical operation of the wireless device based on the program / code / command / information stored in the memory unit (130). The control unit (120) can transmit information stored in the memory unit (130) to the outside (e.g., other communication devices) via the communication unit (110) through a wireless / wired interface, or store information received from the outside (e.g., other communication devices) via the communication unit (110) through a wireless / wired interface in the memory unit (130).

[0076] The additional component (140) may be configured in various ways depending on the type of wireless device. For example, the additional component (140) may include at least one of a power unit / battery, an input / output (I / O) unit, a drive unit, and a computing unit. The wireless device may be implemented in the following forms without limitation: a robot ( Figure 2 100a), vehicles ( Figure 2 100b-1 and 100b-2), XR devices ( Figure 2 100c), handheld devices ( Figure 2 100d), household appliances ( Figure 2 100e), IoT devices ( Figure 2 100f), digital broadcasting terminals, hologram equipment, public safety equipment, MTC equipment, medical equipment, fintech equipment (or financial equipment), security equipment, climate / environmental equipment, AI servers / equipment ( Figure 2 400), BS( Figure 2 200), network nodes, etc. Depending on the use case / service, wireless devices can be used in mobile or fixed places.

[0077] exist Figure 5In the present invention, the various elements, components, units / parts and / or modules in the wireless device (100, 200) can all be connected to each other through a wired interface, or at least part of them can be connected wirelessly through the communication unit (110). For example, in each of the wireless devices (100, 200), the control unit (120) and the communication unit (110) can be connected through a wired interface, and the control unit (120) and the first unit (e.g., 130, 140) can be connected wirelessly through the communication unit (110). Each element, component, unit / part and / or module in the wireless device (100, 200) can also include one or more elements. For example, the control unit (120) can be constructed by a collection of one or more processors. As an example, the control unit (120) can be constructed by a collection of a communication control processor, an application processor, an electronic control unit (ECU), a graphics processing unit and a memory control processor. As another example, the memory ( 130 ) may be constructed by random access memory (RAM), dynamic RAM (DRAM), read only memory (ROM), flash memory, volatile memory, nonvolatile memory, and / or combinations thereof.

[0078] Hereinafter, the implementation will be described in detail with reference to the accompanying drawings. Figure 5 .

[0079] Figure 6 A handheld device according to an embodiment of the present disclosure is shown. The handheld device may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or smart glasses), or a portable computer (e.g., a notebook). The handheld device may be referred to as a mobile station (MS), a user terminal (UT), a mobile subscriber station (MSS), a subscriber station (SS), an advanced mobile station (AMS), or a wireless terminal (WT).

[0080] refer to Figure 6 , the handheld device (100) may include an antenna unit (108), a communication unit (110), a control unit (120), a storage unit (130), a power supply unit (140a), an interface unit (140b) and an I / O unit (140c). The antenna unit (108) may be configured as a part of the communication unit (110). Blocks 110 to 130 / 140a to 140c correspond to Figure 5 Frame 110 to 130 / 140.

[0081] The communication unit 110 can send and receive signals (e.g., data signals and control signals) to and from other wireless devices or base stations. The control unit 120 can perform various operations by controlling the components of the handheld device 100. The control unit 120 may include an application processor (AP). The storage unit 130 can store data / parameters / programs / codes / commands required to operate the handheld device 100. The storage unit 130 can store input / output data / information. The power supply unit 140a can supply power to the handheld device 100 and may include wired / wireless charging circuitry, a battery, etc. The interface unit 140b can support connection between the handheld device 100 and other external devices. The interface unit 140b may include various ports for connecting to external devices (e.g., an audio I / O port and a video I / O port). The I / O unit 140c can input or output user-input video information / signals, audio information / signals, data, and / or information. The I / O unit 140c may include a camera, a microphone, a user input unit, a display unit 140d, a speaker, and / or a haptic module.

[0082] For example, in the case of data communication, the I / O unit 140c can obtain information / signals (e.g., touch, text, voice, image, or video) input by the user, and the obtained information / signals can be stored in the storage unit 130. The communication unit 110 can convert the information / signals stored in the memory into radio signals and transmit the converted radio signals directly to other wireless devices or to the BS. The communication unit 110 can receive radio signals from other wireless devices or BSs and then restore the received radio signals to the original information / signals. The restored information / signals can be stored in the storage unit 130 and can be output as various types (e.g., text, voice, image, video, or tactile) through the I / O unit 140.

[0083] Figure 7 The vehicle or autonomous vehicle according to the embodiment of the present disclosure is shown. The vehicle or autonomous vehicle can be implemented by a mobile robot, a car, a train, a manned / unmanned aerial vehicle (AV), a ship, etc.

[0084] refer to Figure 7 , the vehicle or autonomous vehicle (100) may include an antenna unit (108), a communication unit (110), a control unit (120), a drive unit (140a), a power supply unit (140b), a sensor unit (140c) and an autonomous driving unit (140d). The antenna unit (108) may be configured as a part of the communication unit (110). Blocks 110 / 130 / 140a to 140d correspond to Figure 5 Box 110 / 130 / 140.

[0085] The communication unit 110 can send and receive signals (e.g., data signals and control signals) to and from external devices such as other vehicles, base stations (e.g., gNBs and roadside units), and servers. The control unit 120 can perform various operations by controlling components of the vehicle or autonomous vehicle 100. The control unit 120 may include an electronic control unit (ECU). The drive unit 140a can cause the vehicle or autonomous vehicle 100 to travel on the road. The drive unit 140a may include an engine, a motor, a transmission system, wheels, brakes, a steering device, etc. The power supply unit 140b can supply power to the vehicle or autonomous vehicle 100 and may include a wired / wireless charging circuit, a battery, etc. The sensor unit 140c can obtain vehicle status, external environment information, user information, etc. The sensor unit 140 c may include an inertial measurement unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, a slope sensor, a weight sensor, a heading sensor, a location module, a vehicle forward / backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, a lighting sensor, a pedal position sensor, etc. The autonomous driving unit 140 d may implement a technology for maintaining a lane in which the vehicle is traveling, a technology for automatically adjusting the speed (e.g., adaptive cruise control), a technology for autonomously driving along a determined path, a technology for driving by automatically setting a path with a destination set, etc.

[0086] For example, the communication unit 110 can receive map data, traffic information data, etc. from an external server. The autonomous driving unit 140d can generate an autonomous driving path and driving plan based on the acquired data. The control unit 120 can control the drive unit 140a so that the vehicle or autonomous driving vehicle 100 can move along the autonomous driving path according to the driving plan (e.g., speed / direction control). During autonomous driving, the communication unit 110 can aperiodically / periodically acquire the latest traffic information data from the external server and acquire surrounding traffic information data from neighboring vehicles. During autonomous driving, the sensor unit 140c can acquire vehicle status and / or surrounding environment information. The autonomous driving unit 140d can update the autonomous driving path and driving plan based on the newly acquired data / information. The communication unit 110 can transmit information about the vehicle's location, autonomous driving path, and / or driving plan to the external server. The external server can use AI technology, etc. based on the information collected from the vehicle or autonomous driving vehicle to predict traffic information data and provide the predicted traffic information data to the vehicle or autonomous driving vehicle.

[0087] Figure 8 The structure of the NR system according to an embodiment of the present disclosure is shown. Figure 8 The embodiments of the present disclosure may be combined with various embodiments of the present disclosure.

[0088] refer to Figure 8 , the next generation radio access network (NG-RAN) may include a BS 20 that provides user plane and control plane protocol terminations for the UE 10. For example, the BS 20 may include a next generation Node B (gNB) and / or an evolved Node B (eNB). For example, the UE 10 may be fixed or mobile and may be referred to by other terms such as a mobile station (MS), a user terminal (UT), a subscriber station (SS), a mobile terminal (MT), a wireless device, etc. For example, the BS may be referred to as a fixed station that communicates with the UE 10 and may be referred to by other terms such as a base transceiver system (BTS), an access point (AP), etc.

[0089] Figure 9 The embodiment of the present invention illustrates a case where only gNBs are included. BSs 20 may be connected to each other via an Xn interface. BSs 20 may be connected to each other via a fifth-generation (5G) core network (5GC) and an NG interface. More specifically, BSs 20 may be connected to an access and mobility management function (AMF) 30 via an NG-C interface, and may be connected to a user plane function (UPF) 30 via an NG-U interface.

[0090] Figure 9 The functional division between NG-RAN and 5GC according to an embodiment of the present disclosure is shown. Figure 9 The embodiments of the present disclosure can be combined with various embodiments of the present disclosure.

[0091] refer to Figure 9 The gNB can provide functions such as inter-cell radio resource management (inter-cell RRM), radio bearer (RB) control, connection mobility control, radio admission control, measurement configuration and provisioning, dynamic resource allocation, etc. The AMF can provide functions such as non-access stratum (NAS) security and idle state mobility processing. The UPF can provide functions such as mobility anchoring and protocol data unit (PDU) processing. The session management function (SMF) can provide functions such as user equipment (UE) Internet Protocol (IP) address allocation and PDU session control.

[0092] The radio interface protocol layers between the UE and the network can be categorized as Layer 1 (L1), Layer 2 (L2), and Layer 3 (L3) based on the lower three layers of the Open Systems Interconnection (OSI) model, which is well known in communication systems. The physical (PHY) layer, belonging to Layer 1, provides information transmission services using physical channels, and the radio resource control (RRC) layer, located at Layer 3, controls radio resources between the UE and the network. To this end, the RRC layer exchanges RRC messages between the UE and the base station layer.

[0093] Figure 10 A radio protocol architecture according to an embodiment of the present disclosure is shown. Figure 10 The embodiments of can be combined with various embodiments of the present disclosure. Specifically, Figure 10 (a) shows the radio protocol architecture for the user plane, and Figure 10 (b) in FIG. 4 shows a radio protocol architecture for a control plane. The user plane corresponds to a protocol stack for user data transmission, and the control plane corresponds to a protocol stack for control signal transmission.

[0094] refer to Figure 10 The physical layer provides information transfer services to upper layers via physical channels. The physical layer is connected to the media access control (MAC) layer, which is the upper layer of the physical layer, via transport channels. Data is transferred between the MAC layer and the physical layer via transport channels. Transport channels are categorized based on how data is transmitted over the radio interface and the characteristics of the data being transmitted.

[0095] Data is transmitted between different PHY layers (ie, the PHY layer of the transmitter and the PHY layer of the receiver) through a physical channel. The physical channel may be modulated using an Orthogonal Frequency Division Multiplexing (OFDM) scheme and uses time and frequency as radio resources.

[0096] The MAC layer provides services to the Radio Link Control (RLC) layer, a higher layer above the MAC layer, via logical channels. The MAC layer maps multiple logical channels to multiple transport channels. The MAC layer also provides logical channel multiplexing by mapping multiple logical channels to a single transport channel. The MAC layer provides data transmission services via logical channels.

[0097] The RLC layer performs concatenation, segmentation, and reassembly of radio link control service data units (RLC SDUs). To ensure the different quality of service (QoS) required for radio bearers (RBs), the RLC layer provides three types of operation modes: transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM). AM RLC provides error correction through automatic repeat request (ARQ).

[0098] The Radio Resource Control (RRC) layer is defined only in the control plane. The RRC layer controls physical, transport, and logical channels related to the configuration, reconfiguration, and release of radio bearers. An RB is a logical path provided by Layer 1 (i.e., the PHY layer) and Layer 2 (i.e., the MAC layer, RLC layer, and PDCP layer) to transmit data between the UE and the network.

[0099] The functions of the Packet Data Convergence Protocol (PDCP) in the user plane include transmission of user data, header compression and encryption. The functions of the Packet Data Convergence Protocol (PDCP) in the control plane include transmission and encryption / integrity protection of control plane data.

[0100] The Service Data Adaptation Protocol (SDAP) layer is defined only in the user plane. The SDAP layer performs mapping between Quality of Service (QoS) flows and Data Radio Bearers (DRBs) and QoS Flow ID (QFI) marking in both DL and UL packets.

[0101] RB configuration refers to the process of specifying radio protocol layers and channel attributes to provide a specific service and determining corresponding detailed parameters and operation methods. RBs can then be classified into two types: signaling radio bearers (SRBs) and data radio bearers (DRBs). SRBs are used as a path for transmitting RRC messages in the control plane, and DRBs are used as a path for transmitting user data in the user plane.

[0102] When an RRC connection is established between the RRC layer of the UE and the RRC layer of the E-UTRAN, the UE is in the RRC connected (RRC_CONNECTED) state, otherwise the UE may be in the RRC idle (RRC_IDLE) state. In the case of NR, an RRC inactive (RRC_INACTIVE) state is additionally defined, and the UE in the RRC_INACTIVE state may maintain its connection with the core network while releasing its connection with the BS.

[0103] The downlink transport channels for sending (or transmitting) data from the network to the UE include the broadcast channel (BCH) for sending system information and the downlink shared channel (SCH) for sending other user traffic or control messages. Traffic or control messages for downlink multicast or broadcast services can be sent via the downlink SCH or can be sent via a separate downlink multicast channel (MCH). In addition, the uplink transport channels for sending (or transmitting) data from the UE to the network include the random access channel (RACH) for sending initial control messages and the uplink shared channel (SCH) for sending other user traffic or control messages.

[0104] Examples of logical channels belonging to a higher layer of a transport channel and mapped to a transport channel may include a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), a multicast traffic channel (MTCH), etc.

[0105] A physical channel is configured from multiple OFDM symbols in the time domain and multiple subcarriers in the frequency domain. A subframe is configured from multiple OFDM symbols in the time domain. A resource block is configured from multiple subcarriers and multiple OFDM symbols in a resource allocation unit. In addition, each subframe can use specific subcarriers of specific OFDM symbols (e.g., the first OFDM symbol) of the corresponding subframe of the physical downlink control channel (PDCCH), i.e., the L1 / L2 control channel. The transmission time interval (TTI) refers to the unit time for subframe transmission.

[0106] Figure 11 The structure of the NR system according to an embodiment of the present disclosure is shown. Figure 11 The embodiments of the present disclosure may be combined with various embodiments of the present disclosure.

[0107] refer to Figure 11 In NR, a radio frame can be used to perform uplink and downlink transmissions. The length of a radio frame is 10ms and can be defined as consisting of two half frames (HF). A half frame can include five 1ms subframes (SF). A subframe (SF) can be divided into one or more time slots, and the number of time slots within a subframe can be determined according to the subcarrier spacing (SCS). Each time slot can include 12 or 14 OFDM (A) symbols depending on the cyclic prefix (CP).

[0108] When using a normal CP, each time slot can include 14 symbols. When using an extended CP, each time slot can include 12 symbols. Herein, a symbol may include an OFDM symbol (or a CP-OFDM symbol) and a single carrier-FDMA (SC-FDMA) symbol (or a discrete Fourier transform spread OFDM (DFT-s-OFDM) symbol).

[0109] Table 1 shown below shows the number of symbols (N) per time slot according to the SCS setting (μ) when a normal CP is adopted. slot symb ), the number of time slots per frame (N frame,μ slot ) and the number of time slots per subframe (N subframe,μ slot ).

[0110] [Table 1]

[0111] <![CDATA[SCS(15*2 μ )]]> <![CDATA[N slot symb ]]> <![CDATA[N frame,μ slot ]]> <![CDATA[N subframe,μ slot ]]> 15KHz (μ=0) 14 10 1 30KHz (μ=1) 14 20 2 60KHz (μ=2) 14 40 4 120KHz (μ=3) 14 80 8 240KHz (μ=4) 14 160 16

[0112] Table 2 shows an example of the number of symbols per slot, the number of slots per frame, and the number of slots per subframe according to the SCS in the case of using the extended CP.

[0113] [Table 2]

[0114] <![CDATA[SCS(15*2 μ )]]> <![CDATA[N slot symb ]]> <![CDATA[N frame,μ slot ]]> <![CDATA[N subframe,μ slot ]]> 60KHz (μ=2) 12 40 4

[0115] In the NR system, OFDM(A) parameter sets (e.g., SCS, CP length, etc.) may be configured differently between multiple cells integrated into one UE. Therefore, the (absolute time) duration (or interval) of a time resource (e.g., subframe, time slot, or TTI) (collectively referred to as a time unit (TU) for simplicity) consisting of the same number of symbols may be configured differently in the integrated cells.

[0116] In NR, multiple parameter sets or SCSs can be supported to support various 5G services. For example, with an SCS of 15kHz, a wide range of traditional cellular frequency bands can be supported, and with an SCS of 30kHz / 60kHz, dense urban areas, lower latency, and wider carrier bandwidths can be supported. With an SCS of 60kHz or higher, bandwidths greater than 24.25GHz can be used to overcome phase noise.

[0117] The NR frequency band can be defined as two different types of frequency ranges. The two different types of frequency ranges may be FR1 and FR2. The values ​​of the frequency ranges may be changed (or varied), for example, the two different types of frequency ranges may be as shown in Table 3 below. Among the frequency ranges used in the NR system, FR1 may mean "a range below 6 GHz", and FR2 may mean "a range above 6 GHz", and may also be referred to as millimeter wave (mmW).

[0118] [Table 3]

[0119] Frequency range specification Corresponding frequency range Subcarrier spacing (SCS) FR1 450MHz–6000MHz 15, 30, 60kHz FR2 24250MHz–52600MHz 60, 120, 240kHz

[0120] As described above, the value of the frequency range in the NR system can be changed (or varied). For example, as shown in Table 4 below, FR1 may include a bandwidth in the range of 410 MHz to 7125 MHz. More specifically, FR1 may include frequency bands of 6 GHz (or 5850, 5900, 5925 MHz, etc.) and higher. For example, the frequency bands of 6 GHz (or 5850, 5900, 5925 MHz, etc.) and higher included in FR1 may include unlicensed bands. The unlicensed bands may be used for various purposes, for example, the unlicensed bands are used for vehicle-specific communications (e.g., autonomous driving).

[0121] [Table 4]

[0122] Frequency range specification Corresponding frequency range Subcarrier spacing (SCS) FR1 410MHz–7125MHz 15, 30, 60kHz FR2 24250MHz–52600MHz 60, 120, 240kHz

[0123] Figure 12 The structure of the time slot of the NR frame according to an embodiment of the present disclosure is shown. Figure 12The embodiments of the present disclosure can be combined with various embodiments of the present disclosure.

[0124] refer to Figure 12 A slot includes multiple symbols in the time domain. For example, in the case of normal CP, one slot may include 14 symbols. For example, in the case of extended CP, one slot may include 12 symbols. Alternatively, in the case of normal CP, one slot may include 7 symbols. However, in the case of extended CP, one slot may include 6 symbols.

[0125] A carrier includes multiple subcarriers in the frequency domain. A resource block (RB) can be defined as multiple consecutive subcarriers in the frequency domain (e.g., 12 subcarriers). A bandwidth part (BWP) can be defined as multiple consecutive (physical) resource blocks ((P)RBs) in the frequency domain, and a BWP can correspond to a parameter set (e.g., SCS, CP length, etc.). A carrier can include up to N BWPs (e.g., 5 BWPs). Data communication can be performed via activated BWPs. Each element can be referred to as a resource element (RE) in a resource grid, and a complex symbol can be mapped to each element.

[0126] In addition, the radio interface between a UE and another UE or between a UE and a network may include an L1 layer, an L2 layer, and an L3 layer. In various embodiments of the present disclosure, the L1 layer may refer to a physical layer. In addition, for example, the L2 layer may refer to at least one of a MAC layer, an RLC layer, a PDCP layer, and an SDAP layer. In addition, for example, the L3 layer may refer to an RRC layer.

[0127] Hereinafter, the bandwidth part (BWP) and the carrier will be described in detail.

[0128] A BWP may be a contiguous set of physical resource blocks (PRBs) within a given parameter set. A PRB may be selected from a contiguous set of common resource blocks (CRBs) for a given parameter set on a given carrier.

[0129] When bandwidth adaptation (BA) is used, the reception bandwidth and transmission bandwidth of the user equipment (UE) do not need to be as wide (or large) as the bandwidth of the cell, and the reception bandwidth and transmission bandwidth of the UE can be controlled (or adjusted). For example, the UE can receive information / configuration for bandwidth control (or adjustment) from the network / base station. In this case, bandwidth control (or adjustment) can be performed based on the received information / configuration. For example, bandwidth control (or adjustment) can include reducing / expanding the bandwidth, changing the position of the bandwidth, or changing the subcarrier spacing of the bandwidth.

[0130] For example, the bandwidth can be reduced during periods of low activity to save power. For example, the bandwidth can be relocated (or moved) in the frequency domain. For example, the bandwidth can be relocated (or moved) in the frequency domain to enhance scheduling flexibility. For example, the subcarrier spacing of the bandwidth can be changed. For example, the subcarrier spacing of the bandwidth can be changed to authorize different services. A subset of the total cell bandwidth of a cell can be referred to as a bandwidth part (BWP). BA can be performed when the base station / network configures a BWP for the UE and when the base station / network notifies the UE of the currently active BWP among the BWPs.

[0131] For example, the BWP may be one of an activated BWP, an initial BWP, and / or a default BWP. For example, the UE cannot monitor the downlink radio link quality in DL BWPs other than the activated DL BWP within the primary cell (PCell). For example, the UE cannot receive PDCCH, physical downlink shared channel (PDSCH), or channel state information reference signal (CSI-RS) (except for RRM) from outside the activated DL BWP. For example, the UE cannot trigger channel state information (CSI) reporting for an inactive DL BWP. For example, the UE cannot send physical uplink control channel (PUCCH) or physical uplink shared channel (PUSCH) from outside the inactive DL BWP. For example, in the downlink, the initial BWP may be given as a set of contiguous RBs for the remaining minimum system information (RMSI) control resource set (CORESET) (configured by the physical broadcast channel (PBCH)). For example, in the uplink, the initial BWP may be given by the system information block (SIB) for the random access procedure. For example, the default BWP may be configured by higher layers. For example, the initial value of the default BWP may be the initial DL BWP. To save energy, if the UE cannot detect downlink control information (DCI) within a predetermined period of time, the UE may switch the active BWP of the UE to the default BWP.

[0132] In addition, a BWP can be defined for SL. The same SL BWP can be used for transmission and reception. For example, a transmitting UE can send a SL channel or SL signal within a specific BWP, and a receiving UE can receive a SL channel or SL signal within the same specific BWP. In a licensed carrier, the SL BWP can be defined separately from the Uu BWP, and the SL BWP can have configuration signaling separate from the Uu BWP. For example, the UE can receive a configuration for the SL BWP from the base station / network. The SL BWP can be configured (in advance) for NR V2X UEs and RRC_IDLE UEs out of coverage. For UEs operating in RRC_CONNECTED mode, at least one SL BWP can be activated within the carrier.

[0133] Figure 13 An example of a BWP according to an embodiment of the present disclosure is shown. Figure 13 The embodiments of can be combined with various embodiments of the present disclosure. Figure 13 In the embodiment, the number of BWPs is 3.

[0134] refer to Figure 13 , Common Resource Blocks (CRBs) may be carrier resource blocks numbered from one end of the carrier frequency band to the other. Additionally, PRBs may be resource blocks numbered within each BWP. Point A may indicate a common reference point for the resource block grid.

[0135] It can be obtained by point A, the offset relative to point A (N start BWP ) and bandwidth (N size BWP ) to configure the BWP. For example, point A can be an external reference point of the PRBs of a carrier, and subcarrier 0 of all parameter sets (e.g., all parameter sets supported by the network on the corresponding carrier) is aligned in point A. For example, the offset can be the PRB distance between the lowest subcarrier in a given parameter set and point A. For example, the bandwidth can be the number of PRBs in a given parameter set.

[0136] Hereinafter, V2X or SL communication will be described.

[0137] Figure 14 A radio protocol architecture for SL communication according to an embodiment of the present disclosure is shown. Figure 14 The embodiments of can be combined with various embodiments of the present disclosure. More specifically, Figure 14 (a) in FIG. 1 shows the user plane protocol stack, and Figure 14 (b) in FIG. 5 shows the control plane protocol stack.

[0138] Next, the side link synchronization signal (SLSS) and the synchronization information will be described in detail.

[0139] The SLSS may include a primary sidelink synchronization signal (PSSS) and a secondary sidelink synchronization signal (SSSS) as SL specific sequences. The PSSS may be referred to as a sidelink primary synchronization signal (S-PSS), and the SSSS may be referred to as a sidelink secondary synchronization signal (S-SSS). For example, an M sequence of length 127 may be used for the S-PSS, and a Gold sequence of length 127 may be used for the S-SSS. For example, the UE may use the S-PSS for initial signal detection and synchronization acquisition. For example, the UE may use the S-PSS and the S-SSS for acquiring detailed synchronization and for detecting the synchronization signal ID.

[0140] The physical sidelink broadcast channel (PSBCH) can be a (broadcast) channel for transmitting default (system) information, which must be known by the UE before SL signal transmission / reception. For example, the default information can be information related to SLSS, duplex mode (DM), time division duplex (TDD) uplink / downlink (UL / DL) configuration, information related to resource pool, type of application related to SLSS, subframe offset, broadcast information, etc. For example, in order to evaluate PSBCH performance, in NR V2X, the payload size of PSBCH can be 56 bits, including a 24-bit cyclic redundancy check (CRC).

[0141] S-PSS, S-SSS and PSBCH can be included in a block format that supports periodic transmission (e.g., SL synchronization signal (SS) / PSBCH block, hereinafter, sidelink synchronization signal block (S-SSB)). The S-SSB can have the same parameter set (i.e., SCS and CP length) as the physical sidelink control channel (PSCCH) / physical sidelink shared channel (PSSCH) in the carrier, and the transmission bandwidth can exist within the (pre-) configured sidelink (SL) BWP. For example, the S-SSB can have a bandwidth of 11 resource blocks (SBs). For example, the PSBCH can exist across 11 RBs. In addition, the frequency position of the S-SSB can be (pre-) configured. Therefore, the UE does not have to perform hypothesis detection at the frequency to discover the S-SSB in the carrier.

[0142] Figure 15 A UE performing V2X or SL communication according to an embodiment of the present disclosure is shown. Figure 15 The embodiments of the present disclosure may be combined with various embodiments of the present disclosure.

[0143] refer to Figure 15 In V2X or SL communication, the term "UE" generally refers to a user's UE. However, if a network device such as a base station (BS) transmits / receives signals according to a communication scheme between UEs, the BS may also be considered a type of UE. For example, UE 1 may be first device 100, and UE 2 may be second device 200.

[0144] For example, UE 1 can select a resource unit corresponding to a specific resource from a resource pool representing a set of resources. Furthermore, UE 1 can transmit an SL signal using the resource unit. For example, a resource pool in which UE 1 can transmit a signal can be configured for UE 2, which is a receiving UE, and UE 1's signal can be detected in the resource pool.

[0145] Here, if UE 1 is within the connection range of the BS, the BS can inform UE 1 of the resource pool. Otherwise, if UE 1 is out of the connection range of the BS, another UE can inform UE 1 of the resource pool, or UE 1 can use a pre-configured resource pool.

[0146] Generally, a resource pool may be configured in units of multiple resources, and each UE may select one or more units of resources to use in its SL signaling.

[0147] Hereinafter, resource allocation in SL will be described.

[0148] Figure 16 A process of performing V2X or SL communication by a UE based on a transmission mode according to an embodiment of the present disclosure is shown. Figure 16 The embodiments of the present disclosure may be combined with the various embodiments of the present disclosure. In the various embodiments of the present disclosure, a transmission mode may be referred to as a mode or a resource allocation mode. Hereinafter, for ease of explanation, in LTE, a transmission mode may be referred to as an LTE transmission mode. In NR, a transmission mode may be referred to as an NR resource allocation mode.

[0149] For example, Figure 16 (a) in FIG. 1 shows UE operations related to LTE transmission mode 1 or LTE transmission mode 3. Alternatively, for example, Figure 16 (a) in FIG. 4 shows UE operations related to NR resource allocation mode 1. For example, LTE transmission mode 1 can be applied to conventional SL communication, and LTE transmission mode 3 can be applied to V2X communication.

[0150] For example, Figure 16 (b) in FIG. 4 shows UE operations related to LTE transmission mode 2 or LTE transmission mode 4. Alternatively, for example, Figure 16 (b) in FIG. 4 shows UE operations related to NR resource allocation mode 2.

[0151] refer to Figure 16 In (a), in LTE transmission mode 1, LTE transmission mode 3, or NR resource allocation mode 1, the BS may schedule SL resources to be used by the UE for SL transmission. For example, the BS may perform resource scheduling for UE 1 via the PDCCH (more specifically, downlink control information (DCI)), and UE 1 may perform V2X or SL communication with UE 2 according to the resource scheduling. For example, UE 1 may transmit sidelink control information (SCI) to UE 2 via the physical sidelink control channel (PSCCH), and thereafter transmit data based on the SCI to UE 2 via the physical sidelink shared channel (PSSCH).

[0152] refer to Figure 16(b) in LTE transmission mode 2, LTE transmission mode 4 or NR resource allocation mode 2, the UE can determine the SL transmission resources within the SL resources configured by the BS / network or the pre-configured SL resources. For example, the configured SL resources or the pre-configured SL resources can be a resource pool. For example, the UE can autonomously select or schedule resources for SL transmission. For example, the UE can perform SL communication by autonomously selecting resources in the configured resource pool. For example, the UE can autonomously select resources within the selection window by performing sensing and resource (re)selection processes. For example, sensing can be performed in units of subchannels. In addition, UE 1, which has autonomously selected resources in the resource pool, can send SCI to UE 2 via PSCCH, and thereafter send data based on the SCI to UE 2 via PSSCH.

[0153] Figure 17 Three playback types according to an embodiment of the present disclosure are shown. Figure 17 The embodiments of can be combined with various embodiments of the present disclosure. Specifically, Figure 17 (a) shows a broadcast type SL communication, Figure 17 (b) in FIG. 4 shows unicast type SL communication, and Figure 17 (c) in FIG. 5 shows multicast SL communication. In the case of unicast SL communication, the UE can perform one-to-one communication with another UE. In the case of multicast SL transmission, the UE can perform SL communication with one or more UEs in the group to which the UE belongs. In various embodiments of the present disclosure, SL groupcast communication can be replaced by SL multicast communication, SL one-to-many communication, etc.

[0154] Figure 18 FIG2 shows a synchronization source or synchronization reference of V2X according to an embodiment of the present disclosure. Figure 18 The embodiments of the present disclosure may be combined with various embodiments of the present disclosure.

[0155] refer to Figure 18 In V2X, the UE can synchronize directly with the Global Navigation Satellite System (GNSS), or it can synchronize indirectly with the GNSS through a UE that synchronizes directly with the GNSS (within or outside the network coverage). If the GNSS is configured as the synchronization source, the UE can calculate the Direct Frame Number (DFN) and subframe number by using the Coordinated Universal Time (UTC) and a (pre-)configured DFN offset.

[0156] Alternatively, the UE may synchronize directly with the BS, or may synchronize with another UE that is time / frequency synchronized with the BS. For example, the BS may be an eNB or gNB. For example, when the UE is within network coverage, the UE may receive synchronization information provided by the BS and may synchronize directly with the BS. Thereafter, the UE may provide synchronization information to another adjacent UE. If BS timing is configured based on synchronization, for synchronization and downlink measurements, the UE may rely on the cell associated with the corresponding frequency (when it is within cell coverage at that frequency) or the primary cell or serving cell (when it is outside cell coverage at that frequency).

[0157] A BS (e.g., a serving cell) may provide a synchronization configuration for a carrier used for V2X or SL communication. In this case, the UE may conform to the synchronization configuration received from the BS. If the UE cannot detect any cells in the carrier used for V2X or SL communication and cannot receive a synchronization configuration from the serving cell, the UE may conform to the pre-configured synchronization configuration.

[0158] Alternatively, the UE may synchronize with another UE that is unable to obtain synchronization information directly or indirectly from the BS or GNSS. The synchronization source or preference may be pre-configured for the UE. Alternatively, the synchronization source and preference may be configured via a control message provided by the BS.

[0159] The SL synchronization source may be associated / correlated with the synchronization priority. For example, the relationship between the synchronization source and the synchronization priority may be defined as shown in Table 5 or Table 6. Table 5 or Table 6 is for exemplary purposes only, and the relationship between the synchronization source and the synchronization priority may be defined in various forms.

[0160] [Table 5]

[0161] Priority Level GNSS-based synchronization eNB / gNB-based synchronization P0 GNSS BS P1 All UEs synchronized directly with GNSS All UEs synchronized directly with the BS P2 All UEs indirectly synchronized with GNSS All UEs that are indirectly synchronized with the BS P3 All other UEs GNSS P4 N / A All UEs synchronized directly with GNSS P5 N / A All UEs indirectly synchronized with GNSS P6 N / A All other UEs

[0162] [Table 6]

[0163] Priority Level GNSS-based synchronization eNB / gNB-based synchronization P0 GNSS BS P1 All UEs synchronized directly with GNSS All UEs synchronized directly with the BS P2 All UEs indirectly synchronized with GNSS All UEs that are indirectly synchronized with the BS P3 BS GNSS P4 All UEs synchronized directly with the BS All UEs synchronized directly with GNSS P5 All UEs that are indirectly synchronized with the BS All UEs indirectly synchronized with GNSS P6 Other UEs with low priority Other UEs with low priority

[0164] In Table 5 or Table 6, P0 may represent the highest priority and P6 may represent the lowest priority. In Table 5 or Table 6, the BS may include at least one of a gNB and an eNB.

[0165] It may be (pre-)configured whether GNSS based synchronization or BS based synchronization is used.In single carrier operation, the UE may derive its transmit timing from the highest priority available synchronization reference.

[0166] Hereinafter, carrier reselection will be described.

[0167] In V2X or SL communication, the UE may perform carrier reselection based on the configured carrier's channel busy rate (CBR) and / or the ProSe per-packet priority (PPP) of the V2X message to be sent. For example, carrier reselection may be performed by the MAC layer of the UE.

[0168] The CBR may refer to the portion of subchannels in the resource pool where the sidelink received signal strength indicator (S-RSSI) measured by the UE is detected to be greater than a pre-configured threshold. There is a PPPP associated with each logical channel, and the configuration of the PPPP value will reflect the required latency in both the UE and the base station. During carrier reselection, the UE can select one or more carriers from among the candidate carriers in ascending order of CBR, starting with the lowest CBR.

[0169] Meanwhile, in the present disclosure, for example, a transmitting UE (TX UE) may be a UE that transmits data to a (target) receiving UE (RX UE). For example, the TX UE may be a UE that performs PSCCH transmission and / or PSSCH transmission. Additionally / alternatively, the TX UE may be a UE that transmits a SL CSI-RS and / or a SL CSI report request indicator to a (target) RX UE. Additionally / alternatively, the TX UE may be a UE that transmits a (control) channel (e.g., PSCCH, PSSCH, etc.) and / or a reference signal (e.g., DM-RS, CSI-RS, etc.) on a (control) channel to be used for SL RLM operation and / or SL RLF operation of the (target) RX UE.

[0170] Meanwhile, in the present disclosure, for example, a receiving UE (RX UE) may be a UE that transmits SL HARQ feedback to a transmitting UE (TX UE) based on whether decoding of data received from the TX UE is successful and / or whether detection / decoding of a PSCCH (related to PSSCH scheduling) transmitted by the TX UE is successful. Additionally / alternatively, the RX UE may be a UE that performs SL CSI transmission to the TX UE based on an SLCSI-RS and / or an SL CSI report request indicator received from the TX UE. Additionally / alternatively, the RX UE may be a UE that transmits an SL (L1) RSRP measurement value measured based on a (predefined) reference signal and / or an SL (L1) RSRP report request indicator received from the TX UE to the TX UE. Additionally / alternatively, the RX UE may be a UE that transmits data of the RX UE to the TX UE. Additionally / alternatively, the RX UE may be a UE that performs a SL RLM operation and / or a SL RLF operation based on a (pre-configured) (control) channel and / or a reference signal on a (control) channel received from the TX UE.

[0171] Meanwhile, in the present disclosure, for example, when the RX UE transmits SLHARQ feedback information for the PSSCH and / or PSCCH received from the TX UE, the following options or some of the following options may be considered. Here, for example, the following options or some of the following options may be applied restrictively only when the RX UE successfully decodes / detects the PSCCH that schedules the PSSCH.

[0172] Option 1) NACK information may be sent to the TX UE only when the RX UE fails to decode / receive the PSSCH received from the TX UE.

[0173] Option 2) If the RX UE successfully decodes / receives the PSSCH received from the TX UE, ACK information may be sent to the TX UE, and if the RX UE fails to decode / receive the PSSCH, NACK information may be sent to the TX UE.

[0174] Meanwhile, in the present disclosure, for example, the TX UE may send the following information or some of the following information to the RX UE via the SCI. Here, for example, the TX UE may send some or all of the following information to the RX UE via the first SCI and / or the second SCI.

[0175] -PSSCH (and / or PSCCH) related resource allocation information (e.g., location / number of time / frequency resources, resource reservation information (e.g., period))

[0176] -SL CSI report request indicator or SL (L1) RSRP (and / or SL (L1) RSRQ and / or SL (L1) RSSI) report request indicator

[0177] -SL CSI transmission indicator (or SL (L1) RSRP (and / or SL (L1) RSRQ and / or SL (L1) RSSI) information transmission indicator) (on PSSCH)

[0178] - Modulation and Coding Scheme (MCS) information

[0179] -TX power information

[0180] - L1 destination ID information and / or L1 source ID information

[0181] -SL HARQ process ID information

[0182] -NDI Information

[0183] -RV Information

[0184] - (Transmission service / packet related) QoS information (e.g. priority information)

[0185] -SL CSI-RS transmission indicator or information about the number of antenna ports used for (transmitting) SL CSI-RS

[0186] -TX UE location information or the location (or distance range) information of the target RX UE (for which SL HARQ feedback is requested)

[0187] Reference signal (e.g., DM-RS, etc.) information related to decoding (and / or channel estimation) of data transmitted via the PSSCH. For example, information related to the (time-frequency) mapping resource pattern of the DM-RS, RANK information, antenna port index information, etc.

[0188] Meanwhile, in the present disclosure, for example, because the TX UE can transmit the SCI, the first SCI, and / or the second SCI to the RX UE via the PSCCH, the PSCCH can be replaced / replaced by the SCI and / or the first SCI and / or the second SCI. Additionally / alternatively, the SCI can be replaced / replaced by the PSCCH and / or the first SCI and / or the second SCI. Additionally / alternatively, for example, because the TX UE can transmit the second SCI to the RX UE via the PSSCH, the PSSCH can be replaced / replaced by the second SCI.

[0189] Meanwhile, in the present disclosure, for example, if the SCI configuration field is divided into two groups in consideration of a (relatively) high SCI payload size, the first SCI including the first SCI configuration field group may be referred to as the first SCI, and the second SCI including the second SCI configuration field group may be referred to as the second SCI. Furthermore, for example, the first SCI may be transmitted to the receiving UE via the PSCCH. Furthermore, for example, the second SCI may be transmitted to the receiving UE via a (standalone) PSCCH, or may be piggybacked on the PSSCH and transmitted together with the data.

[0190] Meanwhile, in the present disclosure, for example, “configuration” or “definition” may mean (pre-)configuration (through predefined signaling (eg, SIB, MAC, RRC, etc.)) from a base station or a network (for each resource pool).

[0191] Meanwhile, in the present disclosure, for example, since RLF may be determined based on an out-of-sync (OOS) indicator or an in-sync (IS) indicator, RLF may be replaced / substituted by an out-of-sync (OOS) indicator or an in-sync (IS) indicator.

[0192] Meanwhile, in the present disclosure, for example, RB may be replaced / substituted by a subcarrier. In addition, in the present disclosure, for example, a packet or service may be replaced / substituted by a TB or a MAC PDU based on a transport layer.

[0193] Meanwhile, in the present disclosure, CBG or CG may be replaced / substituted by TB.

[0194] Meanwhile, in the present disclosure, for example, the source ID may be replaced / substituted by the destination ID.

[0195] Meanwhile, in the present disclosure, for example, L1 ID may be replaced / substituted by L2 ID. For example, L1 ID may be L1 source ID or L1 destination ID. For example, L2 ID may be L2 source ID or L2 destination ID.

[0196] Meanwhile, in the present disclosure, for example, the operation of the sending UE reserving / selecting / determining retransmission resources may include: the sending UE reserving / selecting / determining the potential retransmission resources that it will actually use based on the SL HARQ feedback information received from the receiving UE.

[0197] Meanwhile, in the present disclosure, SL mode 1 may refer to a resource allocation method or communication method in which a base station directly schedules a UE's sidelink transmission (SL TX) resources through predefined signaling (e.g., DCI). In addition, SL mode 2 may refer to a resource allocation method or communication method in which a UE independently selects SL TX resources from a resource pool configured or pre-configured from a base station or network, for example.

[0198] Meanwhile, in the present disclosure, for example, for convenience of description, a (physical) channel used when the RX UE transmits at least one of the following information to the TX UE may be referred to as a PSFCH.

[0199] -SL HARQ feedback, SL CSI, SL (L1) RSRP

[0200] Meanwhile, in the present disclosure, the base station may include at least one of a gNB and an eNB.

[0201] Based on the embodiments of the present disclosure, in the case of SL communication, the network / base station may configure or pre-configure information for the UE regarding which entity, between the base station and the GNSS, has a (relatively) high priority for time synchronization and / or frequency synchronization. For example, the network / base station may send information to the UE regarding which entity, between the base station and the GNSS, has a high synchronization priority. For example, this information may be sl-SyncPriority.

[0202] For example, the base station may send the SL-FreqConfigCommon information element (IE) to the UE. For example, Table 7 shows the SL-FreqConfigCommon IE.

[0203] [Table 7]

[0204]

[0205] Referring to Table 7, the SL-FreqConfigCommon IE may include sl-SyncPriority and / or sl-NbAsSync. For example, sl-SyncPriority may indicate / represent a synchronization priority order. For example, sl-NbAsSync may indicate / represent whether a base station / network can be selected as a synchronization reference. For example, if the UE receives an sl-SyncPriority indicating / representing gnss from a base station, the UE may determine that GNSS has the highest synchronization priority, and the UE may select a synchronization reference based on the priority related to GNSS-based synchronization (i.e., the left column) of Table 5, Table 6, or Table 8. For example, if the UE receives an sl-SyncPriority indicating / representing gnbEnb from a base station, the UE may determine that the base station has the highest synchronization priority, and the UE may select a synchronization reference based on the priority related to BS-based synchronization (eNB / gNB-based synchronization) (i.e., the right column) of Table 5, Table 6, or Table 8. For example, if the UE does not receive sl-SyncPriority from the base station, the UE may determine that GNSS has the highest synchronization priority, and the UE may select a synchronization reference based on the priority related to GNSS-based synchronization of Table 5, Table 6, or Table 8 (i.e., the left column).

[0206] For example, if the base station is set to a (relatively) higher priority than the GNSS (for example, if sl-SyncPriority indicates / represents gnbEnb), the UE may consider / determine the priority of the synchronization source / reference based on the right column of Table 5, Table 6, or Table 8 (i.e., the priority related to BS-based synchronization). On the other hand, for example, if the GNSS is set to a (relatively) higher priority than the base station (for example, if sl-SyncPriority indicates / represents gnss or sl-SyncPriority is not configured), the UE may consider / determine the priority of the synchronization source / reference based on the left column of Table 5, Table 6, or Table 8 (i.e., the priority related to GNSS-based synchronization).

[0207] [Table 8]

[0208]

[0209] Here, for example, in the term "priority X" in Table 8, a (relatively) smaller X value may refer to a higher priority. For example, priority 0 may be a higher priority than priority 1, and priority 1 may be a higher priority than priority 2.

[0210] Based on embodiments of the present disclosure, information related to whether a base station is (potentially) present can be signaled / sent by the network or base station to the UE. For example, for each carrier, information related to whether a base station is (potentially) present can be signaled / sent by the network or base station to the UE. For example, for each resource pool, information related to whether a base station is (potentially) present can be signaled / sent by the network or base station to the UE. For example, for each SL BWP, information related to whether a base station is (potentially) present can be signaled / sent by the network or base station to the UE. For example, information related to whether a base station is (potentially) considered to be a synchronization source / reference can be signaled / sent by the network or base station to the UE. For example, for each carrier, information related to whether a base station is (potentially) considered to be a synchronization source / reference can be signaled / sent by the network or base station to the UE. For example, for each resource pool, information related to whether a base station is (potentially) considered to be a synchronization source / reference can be signaled / sent by the network or base station to the UE. For example, for each SL BWP, information related to whether a base station is (potentially) considered to be a synchronization source / reference can be signaled / sent by the network or base station to the UE. Hereinafter, it will be described in detail with reference to the accompanying drawings.

[0211] Figure 19 The following illustrates a process in which a UE performs synchronization according to an embodiment of the present disclosure. Figure 19 The embodiments of the present disclosure can be combined with various embodiments of the present disclosure.

[0212] refer to Figure 19 In step S1310, the base station / network may send sl-NbAsSync to the UE. For example, sl-NbAsSync may be information related to whether the base station / network (potentially) exists. For example, sl-NbAsSync may indicate / indicate whether the base station / network (potentially) exists. For example, sl-NbAsSync may be information related to whether the base station / network is (potentially) regarded as a synchronization source / reference. For example, sl-NbAsSync may indicate / indicate whether the base station / network is (potentially) regarded as a synchronization source / reference. For example, sl-NbAsSync may be information related to whether the base station / network can be selected as a synchronization reference. For example, sl-NbAsSync may indicate / indicate whether the base station / network can be selected as a synchronization reference. For example, sl-NbAsSync may be configured for the UE for each carrier. For example, sl-NbAsSync may be configured for the UE for each resource pool. For example, sl-NbAsSync may be configured for the UE for each SL BWP.

[0213] In step S1320, the UE may select a synchronization reference based on sl-SyncPriority and / or sl-NbAsSync. For example, the synchronization reference may be at least one of a GNSS, a UE directly synchronized with the GNSS, a UE indirectly synchronized with the GNSS, a base station, a UE directly synchronized with the base station, a UE indirectly synchronized with the base station, and / or a remaining UE with the lowest priority.

[0214] For example, if the UE receives an sl-SyncPriority indicating / indicating gnss from the base station, the UE may select a synchronization reference based on the priorities related to GNSS-based synchronization (i.e., the left column) of Table 5, Table 6, or Table 8. For example, if the UE receives an sl-SyncPriority indicating / indicating gnbEnb from the base station, the UE may select a synchronization reference based on the priorities related to BS-based synchronization (eNB / gNB-based synchronization) (i.e., the right column) of Table 5, Table 6, or Table 8. For example, if the UE does not receive an sl-SyncPriority from the base station, the UE may select a synchronization reference based on the priorities related to GNSS-based synchronization (i.e., the left column) of Table 5, Table 6, or Table 8.

[0215] For example, if the UE selects a synchronization reference based on the priority related to GNSS-based synchronization in Table 5, Table 6, or Table 8 (i.e., the left column), and if sl-NbAsSync indicates / represents that the base station / network cannot be selected as the synchronization reference, then the UE cannot select i) the base station, ii) the UE directly synchronized with the base station, and iii) the UE indirectly synchronized with the base station as the synchronization reference. In this case, the UE can select at least one of the GNSS, the UE directly synchronized with the GNSS, the UE indirectly synchronized with the GNSS, and / or the remaining UEs with the lowest priority as the synchronization reference.

[0216] For example, if the UE selects a synchronization reference based on the priority related to GNSS-based synchronization in Table 5, Table 6, or Table 8 (i.e., the left column), and if sl-NbAsSync indicates / represents that a base station / network can be selected as a synchronization reference, the UE can select i) a base station, ii) a UE directly synchronized with a base station, and iii) a UE indirectly synchronized with a base station as a synchronization reference. In this case, the UE can select at least one of the GNSS, a UE directly synchronized with a GNSS, a UE indirectly synchronized with a GNSS, a base station, a UE directly synchronized with a base station, a UE indirectly synchronized with a base station, and / or the remaining UEs with the lowest priority as a synchronization reference.

[0217] For example, the UE may be configured not to search for or detect BS-related synchronization signals on carriers that signal / indicate that a base station is not (potentially) present. In this disclosure, for convenience of description, BS-related synchronization signals (e.g., synchronization-related signals transmitted by a base station) may be referred to as GE_SYCH. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 3 in the left column of Table 8 on carriers that signal / indicate that a base station is not (potentially) present. Furthermore, for example, the UE may be configured not to search for or detect SL synchronization signals that reference the base station's time synchronization and / or frequency synchronization, or SL synchronization signals derived from the base station's time and / or frequency, on carriers that signal / indicate that a base station is not (potentially) present. In this disclosure, for convenience of description, SL synchronization signals that reference the base station's time synchronization and / or frequency synchronization, or SL synchronization signals derived from the base station's time and / or frequency, may be referred to as SL_SYCH. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on carriers that signal / indicate that a base station is not (potentially) present. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4, priority 5, and / or priority 6 in the left column of Table 8 on a carrier where the base station is signaled / indicated (potentially) not present. On the other hand, for example, the UE may be configured to search for / detect synchronization signals corresponding to priority 3 to priority 5 in the left column of Table 8 on a carrier where the base station is signaled / indicated (potentially) present. In this case, the UE may search for / detect all synchronization signals corresponding to priority 0 to priority 6 in the left column of Table 8 on a carrier where the base station is signaled / indicated (potentially) present.

[0218] For example, the UE may be configured not to search for or detect GE_SYCH on a resource pool that signals / indicates the (potential) absence of a base station. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 3 in the left column of Table 8 on a resource pool that signals / indicates the (potential) absence of a base station. Furthermore, for example, the UE may be configured not to search for or detect SL_SYCH on a resource pool that signals / indicates the (potential) absence of a base station. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on a resource pool that signals / indicates the (potential) absence of a base station. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4, priority 5, and / or priority 6 in the left column of Table 8 on a resource pool that signals / indicates the (potential) absence of a base station. On the other hand, for example, the UE may be configured to search for or detect synchronization signals corresponding to priority 3 to priority 5 in the left column of Table 8 on a resource pool that signals / indicates the (potential) presence of a base station. In this case, the UE may search / detect all synchronization signals corresponding to priority 0 to priority 6 in the left column of Table 8 on the resource pool that signals / indicates the (potential) presence of the base station.

[0219] For example, the UE may be configured not to search for or detect GE_SYCH on a SL BWP that signals or indicates that a base station is (potentially) not present. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 3 in the left column of Table 8 on a SL BWP that signals or indicates that a base station is (potentially) not present. Furthermore, for example, the UE may be configured not to search for or detect SL_SYCH on a SL BWP that signals or indicates that a base station is (potentially) not present. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on a SL BWP that signals or indicates that a base station is (potentially) not present. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4, priority 5, and / or priority 6 in the left column of Table 8 on a SL BWP that signals or indicates that a base station is (potentially) not present. On the other hand, for example, the UE may be configured to search for or detect synchronization signals corresponding to priority 3 to priority 5 in the left column of Table 8 on a SL BWP that signals or indicates that a base station is (potentially) present. In this case, the UE may search / detect all synchronization signals corresponding to priority 0 to priority 6 in the left column of Table 8 on the SL BWP that signals / indicates the (potential) presence of the base station.

[0220] For example, the UE may be configured not to search for / detect GE_SYCH on carriers that signal / indicate that the base station / network does not need to (potentially) be considered as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 3 in the left column of Table 8 on carriers that signal / indicate that the base station / network does not need to (potentially) be considered as a synchronization source / reference. Additionally, for example, the UE may be configured not to search for / detect SL_SYCH on carriers that signal / indicate that the base station / network does not need to (potentially) be considered as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on carriers that signal / indicate that the base station / network does not need to (potentially) be considered as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 and / or priority 6 in the left column of Table 8 on carriers that signal / indicate that the base station / network does not need to (potentially) be considered as a synchronization source / reference. On the other hand, for example, the UE may be configured to search for / detect synchronization signals corresponding to priority levels 3 to 5 in the left column of Table 8 on carriers that signal / indicate that the base station / network needs to (potentially) be considered as a synchronization source / reference. In this case, the UE may search for / detect all synchronization signals corresponding to priority levels 0 to 6 in the left column of Table 8 on carriers that signal / indicate that the base station / network needs to (potentially) be considered as a synchronization source / reference.

[0221] For example, the UE may be configured not to search for / detect GE_SYCH on a resource pool that signals / indicates that the base station / network does not need to (potentially) be considered a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 3 in the left column of Table 8 on a resource pool that signals / indicates that the base station / network does not need to (potentially) be considered a synchronization source / reference. Additionally, for example, the UE may be configured not to search for / detect SL_SYCH on a resource pool that signals / indicates that the base station / network does not need to (potentially) be considered a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on a resource pool that signals / indicates that the base station / network does not need to (potentially) be considered a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 and / or priority 6 in the left column of Table 8 on a resource pool that signals / indicates that the base station / network does not need to (potentially) be considered a synchronization source / reference. On the other hand, for example, the UE may be configured to search for / detect synchronization signals corresponding to priority levels 3 to 5 in the left column of Table 8 on the resource pool that signals / indicates that the base station / network needs to (potentially) be considered as a synchronization source / reference. In this case, the UE may search for / detect all synchronization signals corresponding to priority levels 0 to 6 in the left column of Table 8 on the resource pool that signals / indicates that the base station / network needs to (potentially) be considered as a synchronization source / reference.

[0222] For example, the UE may be configured not to search for / detect GE_SYCH on a SL BWP that signals / indicates that the base station / network does not need to (potentially) be considered as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 3 in the left column of Table 8 on a SL BWP that signals / indicates that the base station / network does not need to (potentially) be considered as a synchronization source / reference. Additionally, for example, the UE may be configured not to search for / detect SL_SYCH on a SL BWP that signals / indicates that the base station / network does not need to (potentially) be considered as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on a SL BWP that signals / indicates that the base station / network does not need to (potentially) be considered as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 and / or priority 6 in the left column of Table 8 on a SL BWP that signals / indicates that the base station / network does not need to (potentially) be considered as a synchronization source / reference. On the other hand, for example, the UE may be configured to search for / detect synchronization signals corresponding to priority 3 to priority 5 in the left column of Table 8 on the SL BWP that signals / indicates that the base station / network needs to (potentially) be considered as a synchronization source / reference. In this case, the UE may search for / detect all synchronization signals corresponding to priority 0 to priority 6 in the left column of Table 8 on the SL BWP that signals / indicates that the base station / network needs to (potentially) be considered as a synchronization source / reference.

[0223] For example, the UE may be configured not to search for or detect GE_SYCH on a carrier that signals / indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 3 in the left column of Table 8 on a carrier that signals / indicates that the base station / network cannot be selected as a synchronization reference. Alternatively, for example, the UE may be configured not to search for or detect SL_SYCH on a carrier that signals / indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on a carrier that signals / indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4, priority 5, and / or priority 6 in the left column of Table 8 on a carrier that signals / indicates that the base station / network cannot be selected as a synchronization reference. Alternatively, for example, the UE may be configured to search for or detect synchronization signals corresponding to priority 3 to priority 5 in the left column of Table 8 on a carrier that signals / indicates that the base station / network can be selected as a synchronization reference. In this case, the UE may search / detect all synchronization signals corresponding to priority 0 to priority 6 in the left column of Table 8 on a carrier that signals / indicates that the base station / network may be selected as a synchronization reference.

[0224] For example, the UE may be configured not to search for / detect GE_SYCH on a resource pool that signals / indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 3 in the left column of Table 8 on a resource pool that signals / indicates that the base station / network cannot be selected as a synchronization reference. In addition, for example, the UE may be configured not to search for / detect SL_SYCH on a resource pool that signals / indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on a resource pool that signals / indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 and / or priority 6 in the left column of Table 8 on a resource pool that signals / indicates that the base station / network cannot be selected as a synchronization reference. On the other hand, for example, the UE may be configured to search for / detect synchronization signals corresponding to priorities 3 to 5 in the left column of Table 8 on a resource pool that signals / indicates that a base station / network can be selected as a synchronization reference. In this case, the UE may search for / detect all synchronization signals corresponding to priorities 0 to 6 in the left column of Table 8 on a resource pool that signals / indicates that a base station / network can be selected as a synchronization reference.

[0225] For example, the UE may be configured not to search for or detect GE_SYCH on an SLBWP that signals or indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 3 in the left column of Table 8 on an SL BWP that signals or indicates that the base station / network cannot be selected as a synchronization reference. Furthermore, for example, the UE may be configured not to search for or detect SL_SYCH on an SL BWP that signals or indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4 and / or priority 5 in the left column of Table 8 on an SL BWP that signals or indicates that the base station / network cannot be selected as a synchronization reference. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 4 and / or priority 5 and / or priority 6 in the left column of Table 8 on an SL BWP that signals or indicates that the base station / network cannot be selected as a synchronization reference. On the other hand, for example, the UE may be configured to search for / detect synchronization signals corresponding to priority 3 to priority 5 in the left column of Table 8 on the SL BWP that signals / indicates that the base station / network can be selected as a synchronization reference. In this case, the UE may search for / detect all synchronization signals corresponding to priority 0 to priority 6 in the left column of Table 8 on the SL BWP that signals / indicates that the base station / network can be selected as a synchronization reference.

[0226] For example, the network / base station may send / signal information to the UE regarding whether the UE applies the rule. For example, the network / base station may send / signal HOP information to the UE regarding the SL_SYCH for which the UE does not perform a search / detection operation. Here, for example, if the HOP value is 0, it may refer to a UE that is directly synchronized with a base station or GNSS. For example, if the HOP value is 1, it may refer to a UE that is synchronized with an SL synchronization signal sent by a UE that is directly synchronized with a base station or GNSS (e.g., an indirectly synchronized UE).

[0227] For example, the rule may be limitedly applied / allowed only when the time synchronization difference between the GNSS and the base station exceeds a preconfigured threshold (e.g., in the case where the signaling base station does not (potentially) exist or the signaling base station / network does not need to (potentially) be considered as a synchronization source / reference). For example, the rule may be limitedly applied / allowed only when the frequency synchronization difference between the GNSS and the base station exceeds a preconfigured threshold (e.g., in the case where the signaling base station does not (potentially) exist or the signaling base station / network does not need to (potentially) be considered as a synchronization source / reference). Here, for example, the network / base station may send / signal to the UE information regarding whether the time synchronization between the GNSS and the base station is aligned. For example, the network / base station may send / signal to the UE information regarding whether the frequency synchronization between the GNSS and the base station is aligned. For example, the network / base station may send / signal to the UE information regarding whether the time synchronization difference between the GNSS and the base station is within a preconfigured threshold error range. For example, the network / base station may send / signal to the UE information regarding whether the frequency synchronization difference between the GNSS and the base station is within a preconfigured threshold error range.

[0228] For example, if GNSS is set to a (relatively) higher priority than the base station (for example, if sl-SyncPriority indicates / represents gnss or sl-SyncPriority is not configured), the UE may select a synchronization reference based on the left column of Table 8. Here, for example, the network / base station may send / signal to the UE an indication / indication that synchronization references / sources corresponding to priority 3, priority 4, and priority 5 cannot be searched / detected. For example, the network / base station may send / signal to the UE information indicating / indicating that synchronization references / sources corresponding to priority 3, priority 4, priority 5, and priority 6 cannot be searched / detected.

[0229] For example, if the base station is set to a (relatively) higher priority than GNSS (for example, if sl-SyncPriority indicates / represents gnbEnb), the UE can select a synchronization reference based on the right column of Table 8. Here, for example, the network / base station may send / signal information to the UE indicating / indicating that synchronization references / sources corresponding to priority 0, priority 1, and priority 2 cannot be searched / detected. For example, the network / base station may send / signal information to the UE indicating / indicating that synchronization references / sources corresponding to priority 0, priority 1, priority 2, and priority 6 cannot be searched / detected.

[0230] Here, if the proposed rule is applied, for example, even if the left column of Table 8 (e.g., GNSS has a (relatively) higher priority than base stations) or the right column of Table 8 (e.g., base stations have a (relatively) higher priority than GNSS) is configured / used for the UE, the UE may search / detect only synchronization signals related to the GNSS (e.g., synchronization signals corresponding to priority 0 in the left column of Table 8) and SL synchronization signals for time synchronization and / or frequency synchronization with reference to the GNSS (or derived from the GNSS) (e.g., SL synchronization signals corresponding to priority 1 and priority 2 (or priority 6) in the left column of Table 8). In other words, for example, if the proposed rule is applied, the UE may search / detect synchronization sources / references without considering priority 3, priority 4, priority 5, and priority 6 in the left column of Table 8. For example, if the proposed rule is applied, the UE may search / detect synchronization sources / references without considering priority 3, priority 4, priority 5, and priority 6 in the left column of Table 8. For example, if the proposed rule is applied, the UE may search / detect synchronization sources / references without considering priority 0, priority 1, and priority 2 in the right column of Table 8. For example, in case the proposed rule is applied, the UE may search / detect the synchronization source / reference without considering priority 0, priority 1, priority 2, and priority 6 in the right column of Table 8.

[0231] For example, i) if the UE is configured so that GNSS is set to a (relatively) higher priority than the base station (e.g., if sl-SyncPriority indicates / represents gnss or sl-SyncPriority is not configured), and ii) if the UE is configured so that it cannot select the base station / network as the synchronization reference (e.g., if sl-NbAsSync is false), the UE may select the synchronization reference based on Table 9 or Table 10.

[0232] [Table 9]

[0233] Priority 0: GNSS Priority 1: UEs synchronized directly with GNSS Priority 2: UEs indirectly synchronized with GNSS Priority 3: Remaining UEs with the lowest priority

[0234] [Table 10]

[0235]

[0236] For example, i) if the UE is configured to set GNSS to a (relatively) higher priority than the base station (e.g., if sl-SyncPriority indicates / represents gnss or sl-SyncPriority is not configured), and ii) if the UE is configured to be able to select the base station / network as the synchronization reference (e.g., if sl-NbAsSync is true), the UE may select the synchronization reference based on Table 11 or Table 12.

[0237] [Table 11]

[0238] Priority 0: GNSS Priority 1: UEs synchronized directly with GNSS Priority 2: UEs indirectly synchronized with GNSS Priority 3: BS Priority 4: UEs directly synchronized with the BS Priority 5: UEs that are indirectly synchronized with the BS Priority 6: Remaining UEs with the lowest priority

[0239] [Table 12]

[0240]

[0241] For example, even when the network / base station sends / signals information to the UE regarding whether the GNSS is (potentially) considered as a synchronization source / reference, the various embodiments of the present disclosure described above can be extended / applied. For example, the information regarding whether the GNSS is (potentially) considered as a synchronization source / reference can be configured for each carrier for the UE. For example, the information regarding whether the GNSS is (potentially) considered as a synchronization source / reference can be configured for each resource pool for the UE. For example, the information regarding whether the GNSS is (potentially) considered as a synchronization source / reference can be configured for each SLBWP for the UE.

[0242] For example, the UE may be configured not to search for or detect GNSS-related synchronization signals on carriers that signal / indicate that the GNSS is not (potentially) required to be considered as a synchronization source / reference. In the present disclosure, for convenience of description, GNSS-related synchronization signals (e.g., synchronization-related signals transmitted by the GNSS) may be referred to as GNS_SYN. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 0 in the left column of Table 8 on carriers that signal / indicate that the GNSS is not (potentially) required to be considered as a synchronization source / reference. For example, the UE may be configured not to search for or detect synchronization signals corresponding to priority 3 in the right column of Table 8 on carriers that signal / indicate that the GNSS is not (potentially) required to be considered as a synchronization source / reference. In addition, for example, the UE may be configured not to search for or detect SL synchronization signals for time synchronization and / or frequency synchronization of a reference GNSS, or SL synchronization signals derived from the time and / or frequency of the GNSS, on carriers that signal / indicate that the GNSS is not (potentially) required to be considered as a synchronization source / reference. In the present disclosure, for convenience of description, the SL synchronization signal for time synchronization and / or frequency synchronization with reference to the GNSS or the SL synchronization signal derived from the time and / or frequency of the GNSS may be referred to as SL_GNSC. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 1 and / or priority 2 in the left column of Table 8 on a carrier that is signaled / indicates that the GNSS does not need to be (potentially) regarded as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 1 and / or priority 2 and / or priority 6 in the left column of Table 8 on a carrier that is signaled / indicates that the GNSS does not need to be (potentially) regarded as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 in the right column of Table 8 on a carrier that is signaled / indicates that the GNSS does not need to be (potentially) regarded as a synchronization source / reference. For example, the UE may be configured not to search for / detect synchronization signals corresponding to priority 4 and / or priority 5 and / or priority 6 in the right column of Table 8 on carriers signaling / indicating that GNSS does not need to be (potentially) considered as a synchronization source / reference. On the other hand, for example, the UE may be configured to search for / detect synchronization signals corresponding to priority 0, priority 1, and priority 2 in the left column of Table 8 on carriers signaling / indicating that GNSS needs to be (potentially) considered as a synchronization source / reference. In this case, the UE may search for / detect all synchronization signals corresponding to priority 0 to priority 6 in the left column of Table 8 on carriers signaling / indicating that GNSS needs to be (potentially) considered as a synchronization source / reference.For example, the UE may be configured to search for / detect synchronization signals corresponding to priority 3, priority 4, and priority 5 in the right column of Table 8 on a carrier that signals / indicates that the GNSS needs to be (potentially) considered as a synchronization source / reference. In this case, the UE may search for / detect all synchronization signals corresponding to priority 0 to priority 6 in the right column of Table 8 on a carrier that signals / indicates that the GNSS needs to be (potentially) considered as a synchronization source / reference. Here, the carrier may be replaced with an SL BWP or a resource pool.

[0243] In step S1330, the UE may obtain synchronization from the synchronization reference selected in step S1320. For example, synchronization may include time synchronization and / or frequency synchronization.

[0244] In step S1340 , the UE may perform SL communication based on the acquired synchronization.

[0245] For example, regardless of whether the rules set forth in this disclosure apply, a UE (from the network or base station) can be configured differently or independently for each service type (permitting per carrier, per resource pool, or per SL BWP). For example, regardless of whether the rules set forth in this disclosure apply, a UE (from the network or base station) can be configured differently or independently for each service priority. For example, regardless of whether the rules set forth in this disclosure apply, a UE (from the network or base station) can be configured differently or independently for each QoS parameter / requirement. For example, regardless of whether the rules set forth in this disclosure apply, a UE (from the network or base station) can be configured differently or independently for each carrier type (e.g., a licensed carrier or an Intelligent Transportation System (ITS) dedicated carrier). For example, regardless of whether the rules set forth in this disclosure apply, a UE (from the network or base station) can be configured differently or independently for each center frequency of a carrier. For example, regardless of whether the rules set forth in this disclosure apply, a UE (from the network or base station) can be configured differently or independently for each resource pool of a carrier. For example, regardless of whether the rules proposed in this disclosure apply, the UE can be configured differently or independently for each UE speed in a carrier (from the network or base station). For example, regardless of whether the rules proposed in this disclosure apply, the UE can be configured differently or independently for each congestion level (e.g., CBR) of a carrier (from the network or base station).

[0246] Figure 20 A method for performing synchronization by a first device according to an embodiment of the present disclosure is shown. Figure 20 The embodiments of the present disclosure can be combined with various embodiments of the present disclosure.

[0247] refer to Figure 20In step S1410, the first device may search for / detect a synchronization source or synchronization reference. For example, the first device may search for / detect a synchronization source or synchronization reference based on various methods and / or procedures disclosed herein. In step S1420, the first device may perform synchronization based on the synchronization source or synchronization reference. For example, the first device may perform synchronization based on the synchronization source or synchronization reference based on various methods and / or procedures disclosed herein. For example, the first device may receive information regarding the priority of the synchronization source or synchronization reference from the network or base station. For example, the network or base station may configure or pre-configure information regarding the priority of the synchronization source or synchronization reference to the first device. For example, the first device may receive information regarding whether a gNB and / or eNB is available for each carrier, each resource pool, or each SL BWP. For example, the network or base station may configure or pre-configure information regarding whether a gNB and / or eNB is available for each carrier, each resource pool, or each SL BWP. For example, the first device may receive information regarding whether a gNB and / or eNB should be potentially considered for each carrier, each resource pool, or each SL BWP from the network or base station. For example, the network or base station may configure or pre-configure information to the first device regarding whether gNB and / or eNB should potentially be considered for each carrier or for each resource pool or for each SL BWP.

[0248] Figure 21 A method for performing synchronization by a second device according to an embodiment of the present invention is shown. Figure 21 The embodiments of the present disclosure can be combined with various embodiments of the present disclosure.

[0249] refer to Figure 21In step S1510, the second device may search for / detect a synchronization source or synchronization reference. For example, the second device may search for / detect a synchronization source or synchronization reference based on various methods and / or procedures disclosed herein. In step S1520, the second device may perform synchronization based on the synchronization source or synchronization reference. For example, the second device may perform synchronization based on the synchronization source or synchronization reference based on various methods and / or procedures disclosed herein. For example, the second device may receive information regarding the priority of the synchronization source or synchronization reference from the network or base station. For example, the network or base station may configure or pre-configure information regarding the priority of the synchronization source or synchronization reference to the second device. For example, the second device may receive information regarding whether a gNB and / or eNB may exist for each carrier, each resource pool, or each SL BWP. For example, the network or base station may configure or pre-configure information regarding whether a gNB and / or eNB may exist for each carrier, each resource pool, or each SL BWP. For example, the second device may receive information regarding whether a gNB and / or eNB should be potentially considered for each carrier, each resource pool, or each SL BWP from the network or base station. For example, the network or base station may configure or pre-configure information to the second device regarding whether gNB and / or eNB should potentially be considered for each carrier or for each resource pool or for each SL BWP.

[0250] Figure 22 A method for a first device to perform wireless communication according to an embodiment of the present disclosure is shown. Figure 22 The embodiments of the present disclosure can be combined with various embodiments of the present disclosure.

[0251] refer to Figure 22In step S1610, the first device may receive first information related to a sidelink (SL) synchronization priority order from a base station (BS). For example, the first information may be set to synchronization based on a global navigation satellite system (GNSS). For example, synchronization references related to GNSS-based synchronization may include GNSS, GNSS-related synchronization references, BS-related synchronization references, and other user equipment (UEs). For example, GNSS-related synchronization references may include UEs directly synchronized with the GNSS and UEs indirectly synchronized with the GNSS. For example, BS-related synchronization references may include the BS, UEs directly synchronized with the BS, and UEs indirectly synchronized with the BS. For example, the GNSS may have a higher synchronization priority than a UE directly synchronized with the GNSS, and a UE directly synchronized with the GNSS may have a higher synchronization priority than a UE indirectly synchronized with the GNSS, and a UE indirectly synchronized with the GNSS may have a higher synchronization priority than the BS, and the BS may have a higher synchronization priority than a UE directly synchronized with the BS, and a UE directly synchronized with the BS may have a higher synchronization priority than a UE indirectly synchronized with the BS, and a UE indirectly synchronized with the BS may have a higher synchronization priority than other UEs. In step S1620, the first device may receive second information from the BS indicating whether the BS-related synchronization reference can be selected as the synchronization source. In step S1630, the first device may synchronize with the GNSS-related synchronization reference and one of the synchronization references of the other UEs based on the second information indicating that the BS-related synchronization reference cannot be selected as the synchronization source.

[0252] In addition, for example, the first device may select a synchronization reference from among the GNSS-related synchronization reference and the other UE based on the second information indicating that the BS-related synchronization reference cannot be selected as the synchronization source. For example, based on the second information indicating that the BS-related synchronization reference cannot be selected as the synchronization source, the BS-related synchronization reference may not be selected as the synchronization reference.

[0253] In addition, for example, the first device may perform synchronization with one synchronization reference among the GNSS-related synchronization reference, the BS-related synchronization reference, and the other UE based on the second information indicating that the BS-related synchronization reference can be selected as the synchronization source.

[0254] For example, the first device may be a device that has not yet selected GNSS as a synchronization reference.

[0255] For example, performing synchronization with a synchronization reference may include obtaining synchronization associated with SL communication based on a synchronization-related signal transmitted by the synchronization reference.

[0256] For example, the other UE may be a UE that is not directly or indirectly synchronized with the GNSS and is not directly or indirectly synchronized with the BS.

[0257] For example, the first device may not detect the synchronization-related signal transmitted by the BS-related synchronization reference based on the second information indicating that the BS-related synchronization reference cannot be selected as the synchronization source.

[0258] For example, the second information may be configured for each carrier, each resource pool, or each frequency.

[0259] In addition, for example, the first device may measure reference signal received power (RSRP) based on a GNSS-related synchronization reference or a synchronization-related signal transmitted by another UE. For example, the RSRP measured based on the synchronization-related signal transmitted by one synchronization reference may exceed a preconfigured threshold. For example, one synchronization reference may have the highest synchronization priority among the GNSS-related synchronization reference and the other UE.

[0260] For example, the second information may be received from the BS based on the synchronization difference between the GNSS and the BS exceeding a preconfigured threshold. For example, the synchronization difference may include at least one of a frequency-related synchronization difference or a time-related synchronization difference.

[0261] The proposed method can be applied to the following devices. First, the processor 102 of the first device 100 can control the transceiver 106 to receive first information related to a side link (SL) synchronization priority order from a base station (BS). For example, the first information can be set to synchronization based on a global navigation satellite system (GNSS). For example, a synchronization reference related to GNSS-based synchronization may include a GNSS, a GNSS-related synchronization reference, a BS-related synchronization reference, and other user equipment (UE). For example, a GNSS-related synchronization reference may include a UE directly synchronized with the GNSS and a UE indirectly synchronized with the GNSS. For example, a BS-related synchronization reference may include a BS, a UE directly synchronized with the BS, and a UE indirectly synchronized with the BS. For example, the GNSS may have a higher synchronization priority than a UE directly synchronized with the GNSS, and the UE directly synchronized with the GNSS may have a higher synchronization priority than a UE indirectly synchronized with the GNSS, and the UE indirectly synchronized with the GNSS may have a higher synchronization priority than the BS, and the BS may have a higher synchronization priority than a UE directly synchronized with the BS, and the UE directly synchronized with the BS may have a higher synchronization priority than a UE indirectly synchronized with the BS, and the UE indirectly synchronized with the BS may have a higher synchronization priority than other UEs. In addition, the processor 102 of the first device 100 may control the transceiver 106 to receive second information from the BS indicating whether the BS-related synchronization reference can be selected as the synchronization source. In addition, the processor 102 of the first device 100 may perform synchronization with a GNSS-related synchronization reference and one of the synchronization references of the other UEs based on the second information indicating that the BS-related synchronization reference cannot be selected as the synchronization source.

[0262] Based on an embodiment of the present disclosure, a first device configured to perform wireless communication may be provided. For example, the first device may include: one or more memories storing instructions; one or more transceivers; and one or more processors connected to the one or more memories and the one or more transceivers. For example, the one or more processors may execute instructions to: receive first information related to a side link (SL) synchronization priority order from a base station (BS), wherein the first information is set to synchronization based on a global navigation satellite system (GNSS), wherein synchronization references related to GNSS-based synchronization include GNSS, GNSS-related synchronization references, BS-related synchronization references, and other user equipment (UEs), wherein GNSS-related synchronization references include UEs directly synchronized with GNSS and UEs indirectly synchronized with GNSS, wherein BS-related synchronization references include BS, UEs directly synchronized with BS, and UEs indirectly synchronized with BS, and wherein GNSS has a higher synchronization priority than UEs directly synchronized with GNSS level, and a UE directly synchronized with the GNSS has a higher synchronization priority than a UE indirectly synchronized with the GNSS, and the UE indirectly synchronized with the GNSS has a higher synchronization priority than the BS, and the BS has a higher synchronization priority than a UE directly synchronized with the BS, and the UE directly synchronized with the BS has a higher synchronization priority than a UE indirectly synchronized with the BS, and the UE indirectly synchronized with the BS has a higher synchronization priority than other UEs; receiving second information from the BS indicating whether the BS-related synchronization reference can be selected as a synchronization source; and performing synchronization with the GNSS-related synchronization reference and one of the synchronization references of the other UEs based on the second information indicating that the BS-related synchronization reference cannot be selected as the synchronization source.

[0263] Based on an embodiment of the present disclosure, a device configured to control a first user equipment (UE) performing wireless communication may be provided. For example, the device may include: one or more processors; one or more memories operably connected to the one or more processors and storing instructions. For example, the one or more processors may execute instructions to: receive first information related to a side link (SL) synchronization priority order from a base station (BS), wherein the first information is set to synchronization based on a global navigation satellite system (GNSS), wherein synchronization references related to GNSS-based synchronization include GNSS, GNSS-related synchronization references, BS-related synchronization references, and other UEs, wherein the GNSS-related synchronization references include UEs directly synchronized with the GNSS and UEs indirectly synchronized with the GNSS, wherein the BS-related synchronization references include BS, UEs directly synchronized with the BS, and UEs indirectly synchronized with the BS, and wherein the GNSS has a higher synchronization priority than the UEs directly synchronized with the GNSS, and and a UE directly synchronized with the GNSS has a higher synchronization priority than a UE indirectly synchronized with the GNSS, and a UE indirectly synchronized with the GNSS has a higher synchronization priority than the BS, and the BS has a higher synchronization priority than a UE directly synchronized with the BS, and a UE directly synchronized with the BS has a higher synchronization priority than a UE indirectly synchronized with the BS, and a UE indirectly synchronized with the BS has a higher synchronization priority than other UEs; receiving second information from the BS indicating whether a BS-related synchronization reference can be selected as a synchronization source; and performing synchronization with the GNSS-related synchronization reference and one of the synchronization references of the other UEs based on the second information indicating that the BS-related synchronization reference cannot be selected as the synchronization source.

[0264] Based on an embodiment of the present disclosure, a non-transitory computer-readable storage medium storing instructions may be provided. For example, when the instructions are executed, a first device may: receive first information related to a sidelink (SL) synchronization priority order from a base station (BS), wherein the first information is set to synchronization based on a global navigation satellite system (GNSS), wherein synchronization references related to GNSS-based synchronization include GNSS, GNSS-related synchronization references, BS-related synchronization references, and other user equipment (UEs), wherein GNSS-related synchronization references include UEs directly synchronized with the GNSS and UEs indirectly synchronized with the GNSS, wherein BS-related synchronization references include BSs, UEs directly synchronized with the BSs, and UEs indirectly synchronized with the BSs, and wherein GNSSs have a higher synchronization priority than UEs directly synchronized with the GNSSs. And the UE directly synchronized with the GNSS has a higher synchronization priority than the UE indirectly synchronized with the GNSS, and the UE indirectly synchronized with the GNSS can have a higher synchronization priority than the BS, and the BS has a higher synchronization priority than the UE directly synchronized with the BS, and the UE directly synchronized with the BS has a higher synchronization priority than the UE indirectly synchronized with the BS, and the UE indirectly synchronized with the BS has a higher synchronization priority than other UEs; receiving second information from the BS indicating whether the BS-related synchronization reference can be selected as the synchronization source; and based on the second information indicating that the BS-related synchronization reference cannot be selected as the synchronization source, performing synchronization with the GNSS-related synchronization reference and one of the synchronization references of the other UEs.

[0265] Figure 23 A method for a first device to perform wireless communication according to an embodiment of the present disclosure is shown. Figure 23 The embodiments of the present disclosure can be combined with various embodiments of the present disclosure.

[0266] refer to Figure 23In step S1710, the first device may receive information related to a sidelink (SL) bandwidth part (BWP). For example, the first device may receive information related to the sidelink (SL) bandwidth part (BWP) from the network. In step S1720, the first device may receive SL synchronization priority order information set for global navigation satellite system (GNSS)-based synchronization from the network. In step S1730, the first device may receive information from the network indicating whether to deactivate selection of a base station (BS)-related synchronization reference. In step S1740, the first device may detect a synchronization signal transmitted by the SL BWP via a GNSS-related synchronization reference or another user equipment (UE) based on the information indicating deactivation of selection of the BS-related synchronization reference. In step S1750, the first device may synchronize with the GNSS-related synchronization reference or one of the other UE synchronization references based on the synchronization signal. For example, synchronization references related to GNSS-based synchronization may include GNSS, GNSS-related synchronization references, BS-related synchronization references, and other UEs. For example, GNSS-related synchronization references may include UEs directly synchronized with the GNSS and UEs indirectly synchronized with the GNSS. For example, the BS-related synchronization reference may include the BS, a UE directly synchronized with the BS, and a UE indirectly synchronized with the BS.

[0267] For example, based on the SL synchronization priority order information, the GNSS-related synchronization reference may be prioritized over the BS-related synchronization reference.

[0268] For example, performing synchronization with a synchronization reference may include obtaining synchronization associated with SL communication based on a synchronization signal transmitted by the synchronization reference through the SL BWP.

[0269] In addition, for example, the first device may select a synchronization reference from among GNSS-related synchronization references and other UEs. For example, based on the information indicating deactivation of selecting a BS-related synchronization reference, the BS-related synchronization reference may not be selected as the synchronization reference.

[0270] For example, the first device may be a device that has not yet selected GNSS as a synchronization reference

[0271] For example, based on the information indicating deactivation of selection of the BS-related synchronization reference, the first device may not detect the synchronization signal transmitted by the BS-related synchronization reference.

[0272] In addition, for example, based on the information indicating that selection of the BS-related synchronization reference is enabled, the first device may detect a synchronization signal transmitted by a GNSS-related synchronization reference, a BS-related synchronization reference, or another UE. In addition, for example, the first device may synchronize with one of the GNSS-related synchronization reference, the BS-related synchronization reference, or the other UE based on the synchronization signal.

[0273] For example, the other UE may be a UE that is not directly or indirectly synchronized with the GNSS and is not directly or indirectly synchronized with the BS.

[0274] For example, information indicating whether to disable selection of a BS-related synchronization reference may be configured for each carrier, each resource pool, or each frequency.

[0275] In addition, for example, the first device may measure a reference signal received power (RSRP) based on a synchronization signal transmitted by a GNSS-related synchronization reference or other UE through the SL BWP. In addition, for example, the first device may determine one or more synchronization references associated with at least one RSRP value exceeding a preconfigured threshold among RSRP values ​​measured for the GNSS-related synchronization reference or other UE. In addition, for example, the first device may select a synchronization reference with the highest synchronization priority among the one or more synchronization references. For example, a GNSS may have a higher synchronization priority than a UE directly synchronized with the GNSS, and a UE directly synchronized with the GNSS may have a higher synchronization priority than a UE indirectly synchronized with the GNSS, and a UE indirectly synchronized with the GNSS may have a higher synchronization priority than a BS, and a BS may have a higher synchronization priority than a UE directly synchronized with the BS, and a UE directly synchronized with the BS may have a higher synchronization priority than a UE indirectly synchronized with the BS, and a UE indirectly synchronized with the BS may have a higher synchronization priority than other UEs.

[0276] The proposed method can be applied to the following devices. First, the processor 102 of the first device 100 can control the transceiver 106 to receive information related to the side link (SL) bandwidth part (BWP). In addition, the processor 102 of the first device 100 can control the transceiver 106 to receive SL synchronization priority order information set to synchronization based on the global navigation satellite system (GNSS) from the network. In addition, the processor 102 of the first device 100 can control the transceiver 106 to receive information from the network indicating whether to deactivate the selection of a base station (BS) related synchronization reference. In addition, the processor 102 of the first device 100 can detect a synchronization signal sent by a GNSS-related synchronization reference or other user equipment (UE) through the SLBWP based on the information indicating the deactivation of the selection of the BS-related synchronization reference. In addition, the processor 102 of the first device 100 can perform synchronization with a GNSS-related synchronization reference or one of the synchronization references of the other UEs based on the synchronization signal. For example, the synchronization reference related to GNSS-based synchronization can include GNSS, GNSS-related synchronization reference, BS-related synchronization reference, and other UEs. For example, a GNSS-related synchronization reference may include a UE directly synchronized with the GNSS and a UE indirectly synchronized with the GNSS. For example, a BS-related synchronization reference may include a BS, a UE directly synchronized with the BS, and a UE indirectly synchronized with the BS.

[0277] Based on an embodiment of the present disclosure, a first device configured to perform wireless communication may be provided. For example, the first device may include: one or more memories storing instructions; one or more transceivers; and one or more processors connected to the one or more memories and the one or more transceivers. For example, the one or more processors may execute instructions to: receive information related to a sidelink (SL) bandwidth part (BWP); receive SL synchronization priority order information related to synchronization set to be based on a global navigation satellite system (GNSS) from a network; receive information from the network indicating whether to deactivate selection of a base station (BS)-related synchronization reference; based on the information indicating deactivation of selection of a BS-related synchronization reference, detect a synchronization signal sent by a GNSS-related synchronization reference or other UE via the SL BWP; and perform synchronization with a GNSS-related synchronization reference or one of the other UEs based on the synchronization signal. For example, synchronization references related to GNSS-based synchronization may include GNSS, GNSS-related synchronization references, BS-related synchronization references, and other UEs, and GNSS-related synchronization references may include UEs directly synchronized with the GNSS and UEs indirectly synchronized with the GNSS, and BS-related synchronization references may include BSs, UEs directly synchronized with the BS, and UEs indirectly synchronized with the BS.

[0278] Based on an embodiment of the present disclosure, an apparatus configured to control a first user equipment (UE) performing wireless communication may be provided. For example, the apparatus may include: one or more processors; and one or more memories operably connected to the one or more processors and storing instructions. For example, the one or more processors may execute instructions to: receive information related to a sidelink (SL) bandwidth part (BWP); receive SL synchronization priority order information related to synchronization set to be based on a global navigation satellite system (GNSS) from a network; receive information from the network indicating whether to deactivate selection of a base station (BS)-related synchronization reference; based on the information indicating deactivation of selection of a BS-related synchronization reference, detect a synchronization signal sent by a GNSS-related synchronization reference or other UE via the SL BWP; and perform synchronization with a GNSS-related synchronization reference or one of the other UEs based on the synchronization signal. For example, synchronization references related to GNSS-based synchronization may include GNSS, GNSS-related synchronization references, BS-related synchronization references, and other UEs, and GNSS-related synchronization references may include UEs directly synchronized with the GNSS, and UEs indirectly synchronized with the GNSS, and BS-related synchronization references may include BSs, UEs directly synchronized with the BSs, and UEs indirectly synchronized with the BSs.

[0279] Based on an embodiment of the present disclosure, a non-transitory computer-readable storage medium storing instructions may be provided. For example, when the instructions are executed, a first device may: receive information related to a sidelink (SL) bandwidth part (BWP); receive SL synchronization priority order information related to synchronization set to be based on a global navigation satellite system (GNSS) from a network; receive information from the network indicating whether to deactivate selection of a base station (BS)-related synchronization reference; based on the information indicating deactivation of selection of a BS-related synchronization reference, detect a synchronization signal sent by a GNSS-related synchronization reference or other user equipment (UE) through the SL BWP; and perform synchronization with a GNSS-related synchronization reference or one of the other UEs based on the synchronization signal. For example, synchronization references related to GNSS-based synchronization may include GNSS, GNSS-related synchronization references, BS-related synchronization references, and other UEs, and GNSS-related synchronization references may include UEs directly synchronized with the GNSS, and UEs indirectly synchronized with the GNSS, and BS-related synchronization references may include BSs, UEs directly synchronized with the BSs, and UEs indirectly synchronized with the BSs.

[0280] Various embodiments of the present disclosure may be combined with each other.

[0281] The claims in this specification can be combined in various ways. For example, the technical features in the method claims of this specification can be combined to be implemented or performed in an apparatus, and the technical features in the apparatus claims can be combined to be implemented or performed in a method. In addition, the technical features in (one or more) method claims and (one or more) apparatus claims can be combined to be implemented or performed in an apparatus. In addition, the technical features in (one or more) method claims and (one or more) apparatus claims can be combined to be implemented or performed in a method.

Claims

1. A method for performing wireless communication by a first device, the method comprising: Obtain information related to the side link SL bandwidth part BWP; obtaining SL synchronization priority order information set for synchronization based on a global navigation satellite system (GNSS); obtaining information indicating whether to deactivate a synchronization reference associated with a selected base station BS; Deactivate the selection of the BS-related synchronization reference based on the information indicating deactivation, and detect a synchronization signal sent by a GNSS-related synchronization reference or other user equipment UE through the SL BWP; as well as Based on the synchronization signal, synchronization is performed with the GNSS-related synchronization reference or one of the other UE synchronization references, The GNSS-related synchronization reference includes a UE directly synchronized with the GNSS and a UE indirectly synchronized with the GNSS. The BS-related synchronization reference includes the BS, the UE directly synchronized with the BS, and the UE indirectly synchronized with the BS, and For a specific carrier, information indicating whether to disable selection of the BS-related synchronization reference is pre-configured in the first device.

2. The method according to claim 1, wherein Based on the SL synchronization priority order information, the GNSS-related synchronization reference takes precedence over the BS-related synchronization reference.

3. The method according to claim 1, wherein Performing synchronization with the one synchronization reference includes obtaining synchronization associated with SL communication based on the synchronization signal transmitted by the one synchronization reference through the SL BWP.

4. The method according to claim 1, further comprising: Selecting the one synchronization reference from among the GNSS-related synchronization references and other UEs, Wherein, based on the information indicating deactivation of selecting the BS-related synchronization reference, the BS-related synchronization reference is not selected as the synchronization reference.

5. The method according to claim 1, wherein The first device is a device that has not yet selected the GNSS as a synchronization reference.

6. The method according to claim 1, wherein Based on the information indicating deactivation of selecting the BS-related synchronization reference, the first device does not detect a synchronization signal sent by the BS-related synchronization reference.

7. The method according to claim 1, further comprising: selecting the BS-related synchronization reference based on the information indicating activation, and detecting a synchronization signal sent by the GNSS-related synchronization reference, the BS-related synchronization reference or another UE; as well as Based on the synchronization signal, synchronization is performed with one of the GNSS-related synchronization reference, the BS-related synchronization reference, or another UE's synchronization reference.

8. The method according to claim 1, wherein Other UEs are UEs that are not directly or indirectly synchronized with the GNSS and are not directly or indirectly synchronized with the BS.

9. The method according to claim 1, further comprising: The reference signal received power (RSRP) is measured based on the synchronization signal sent by the GNSS-related synchronization reference or other UEs through the SL BWP.

10. The method according to claim 9, further comprising: One or more synchronization references are determined that are associated with at least one RSRP value exceeding a preconfigured threshold among RSRP values ​​measured for the GNSS-related synchronization reference or other UEs.

11. The method according to claim 10, further comprising: The one synchronization reference having the highest synchronization priority among the one or more synchronization references is selected.

12. The method according to claim 11, wherein The GNSS has a higher synchronization priority than a UE directly synchronized with the GNSS, and a UE directly synchronized with the GNSS has a higher synchronization priority than a UE indirectly synchronized with the GNSS, and a UE indirectly synchronized with the GNSS has a higher synchronization priority than the BS, and the BS has a higher synchronization priority than a UE directly synchronized with the BS, and a UE directly synchronized with the BS has a higher synchronization priority than a UE indirectly synchronized with the BS, and a UE indirectly synchronized with the BS has a higher synchronization priority than other UEs.

13. A first device configured to perform wireless communication, the first device comprising: at least one transceiver; at least one processor; as well as at least one memory coupled to the at least one processor and storing instructions that, upon being executed, cause the first device to perform operations comprising: Obtain information related to the side link SL bandwidth part BWP; obtaining SL synchronization priority order information set for synchronization based on a global navigation satellite system (GNSS); obtaining information indicating whether to deactivate a synchronization reference associated with a selected base station BS; Based on the information indicating deactivation of selecting the BS-related synchronization reference, detecting a synchronization signal sent by a GNSS-related synchronization reference or other user equipment UE through the SL BWP; and Based on the synchronization signal, synchronization is performed with the GNSS-related synchronization reference or one of the other UE synchronization references, The GNSS-related synchronization reference includes a UE directly synchronized with the GNSS and a UE indirectly synchronized with the GNSS. The BS-related synchronization reference includes the BS, the UE directly synchronized with the BS, and the UE indirectly synchronized with the BS, and For a specific carrier, information indicating whether to disable selection of the BS-related synchronization reference is pre-configured in the first device.

14. An apparatus configured to control a first user equipment (UE) performing wireless communication, the apparatus comprising: at least one processor; as well as At least one memory connected to the at least one processor and storing instructions that, upon being executed, cause the first user device to perform operations comprising: Obtain information related to the side link SL bandwidth part BWP; obtaining SL synchronization priority order information set for synchronization based on a global navigation satellite system (GNSS); obtaining information indicating whether to deactivate a synchronization reference associated with a selected base station BS; Deactivate the selection of the BS-related synchronization reference based on the information indicating deactivation, and detect a synchronization signal sent by a GNSS-related synchronization reference or another UE through the SL BWP; and Based on the synchronization signal, synchronization is performed with the GNSS-related synchronization reference or one of the other UE synchronization references, The GNSS-related synchronization reference includes a UE directly synchronized with the GNSS and a UE indirectly synchronized with the GNSS. The BS-related synchronization reference includes the BS, the UE directly synchronized with the BS, and the UE indirectly synchronized with the BS, and For a specific carrier, information indicating whether to disable selection of the BS-related synchronization reference is pre-configured in the first user equipment.

Images