WO2022005052A1 - Method and device for transmitting signal in wireless communication system - Google Patents

Abstract

Disclosed are a method for operating a terminal in a wireless communication system, and a device for supporting same. One embodiment applicable to the present disclosure comprises steps in which: a terminal transmits at least one discovery signal having each beam direction; and the terminal receives a discovery response signal from the terminal having received the at least one discovery signal. The discovery signal can include a synchronization signal and a discovery message.

Description

Method and apparatus for transmitting a signal in a wireless communication system

The following description relates to a wireless communication system, and to a discovery signal transmission method for initial beam alignment in a wireless communication system.

Also, it relates to a method of transmitting a sidelink-synchronization signal block (S-SSB) for initial beam alignment in a wireless communication system.

In addition, it relates to an efficient beam pairing method in a wireless communication system.

A wireless communication system is a multiple access system that supports communication with multiple users by sharing available system resources (eg, bandwidth, transmission power, etc.). Examples of the multiple access system include a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, and a single carrier frequency (SC-FDMA) system. There is a division multiple access) system, a multi carrier frequency division multiple access (MC-FDMA) system, and the like.

A sidelink (SL) refers to a communication method in which a direct link is established between user equipments (UEs), and voice or data is directly exchanged between UEs without going through a base station (BS). SL is being considered as a method to solve the burden of the base station due to the rapidly increasing data traffic.

V2X (vehicle-to-everything) refers to a communication technology that exchanges information with other vehicles, pedestrians, and infrastructure-built objects through wired/wireless communication. V2X can be divided into four types: vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), and vehicle-to-pedestrian (V2P). V2X communication may be provided through a PC5 interface and/or a Uu interface.

Meanwhile, as more and more communication devices require a larger communication capacity, the need for improved mobile broadband communication compared to the existing radio access technology (RAT) is emerging. Accordingly, a communication system in consideration of a service or terminal sensitive to reliability and latency is being discussed. Improved mobile broadband communication, mMTC (massive machine type communication), URLLC (ultra-reliable and low latency communication) The next-generation radio access technology in consideration of the above may be referred to as a new RAT or new radio (NR). Even in NR, vehicle-to-everything (V2X) communication may be supported.

The present disclosure relates to a beam pairing method and apparatus in a wireless communication system.

The present disclosure relates to a method and apparatus for determining a synchronization signal transmission time in a wireless communication system.

The technical objects to be achieved in the present disclosure are not limited to the above, and other technical problems not mentioned are common knowledge in the technical field to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure to be described below. can be considered by those with

As an example of the present disclosure, the terminal transmitting at least one or more discovery signals having each beam direction, the terminal receiving the discovery response signal from the terminal receiving the at least one or more discovery signals may include The discovery signal may include a synchronization signal and a discovery message. A sequence ID of the synchronization signal may indicate a beam ID based on a beam direction of the discovery signal. The method may include, by the terminal, partial sweeping of the discovery signal based on the beam ID. The discovery response signal may include best beam ID information based on the beam ID. The synchronization signal may include a synchronization signal block, and the synchronization signal block may include a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). The sequence of the PSS and the SSS may be determined based on a sidelink synchronization signal ID (SL-SSID).

As an example of the present disclosure, the terminal may include a transceiver and a processor connected to the transceiver. The processor may control the transceiver to transmit at least one discovery signal having each beam direction. The processor may control to receive a discovery response signal from the terminal that has received the at least one or more discovery signals. The discovery signal may include a synchronization signal and a discovery message. A sequence ID of the synchronization signal may indicate a beam ID based on a beam direction of the discovery signal. The processor may control the transceiver to partially sweep the discovery signal based on the beam ID. The discovery response signal may include best beam ID information based on the beam ID. The synchronization signal may include a synchronization signal block, and the synchronization signal block may include a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). The sequence of the PSS and the SSS may be determined based on a sidelink synchronization signal ID (SL-SSID).

As an example of the present disclosure, the terminal receiving at least one or more discovery signals having each beam direction, and transmitting, by the terminal, a discovery response signal to the terminal that has transmitted the at least one or more discovery signals. may include The discovery signal may include a synchronization signal and a discovery message.

As an example of the present disclosure, the terminal may include a transceiver and a processor connected to the transceiver. The processor may control the transceiver to receive at least one or more discovery signals having each beam direction. The processor may control the transceiver to transmit a discovery response signal to the terminal that has transmitted the one or more discovery signals. The discovery signal may include a synchronization signal and a discovery message.

As an example of the present disclosure, an apparatus may include at least one memory and at least one processor operatively connected to the at least one memories. The at least one processor may control the device to transmit at least one or more discovery signals having respective beam directions. The at least one processor may control the device to receive a discovery response signal from the terminal that has received the at least one or more discovery signals. The discovery signal may include a synchronization signal and a discovery message.

As an example of the present disclosure, a computer-readable medium is a non-transitory (non-transitory) medium storing at least one instruction (instruction)

It may include the at least one instruction executable (executable) by the processor. The at least one instruction may instruct the computer-readable medium to transmit at least one or more discovery signals having respective beam directions. The at least one instruction may instruct the computer-readable medium to receive a discovery response signal from the terminal that has received the at least one or more discovery signals. The discovery signal may include a synchronization signal and a discovery message.

Aspects of the present disclosure described above are only some of the preferred embodiments of the present disclosure, and various embodiments in which the technical features of the present disclosure are reflected are detailed descriptions of the present disclosure that will be described below by those of ordinary skill in the art can be derived and understood based on

The following effects may be obtained by the embodiments based on the present disclosure.

According to the present disclosure, a time taken to perform beam alignment may be reduced.

According to the present disclosure, in mmWave sidelink communication, a receiving terminal may determine a best Tx beam for each transmitting terminal.

According to the present disclosure, the UE may perform initial beam alignment for mmWave sidelink communication.

According to the present disclosure, in mmWave sidelink communication, a UE may transmit a discovery signal by applying Tx beam sweeping.

Effects that can be obtained in the embodiments of the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned are the technical fields to which the technical configuration of the present disclosure is applied from the description of the embodiments of the present disclosure below. It can be clearly derived and understood by those of ordinary skill in the art. That is, unintended effects of implementing the configuration described in the present disclosure may also be derived by those of ordinary skill in the art from the embodiments of the present disclosure.

The accompanying drawings below are provided to help understanding of the present disclosure, and together with the detailed description, may provide embodiments of the present disclosure. However, the technical features of the present disclosure are not limited to specific drawings, and features disclosed in each drawing may be combined with each other to constitute a new embodiment. Reference numerals in each drawing may refer to structural elements.

1 illustrates a structure of a wireless communication system according to an embodiment of the present disclosure.

2 illustrates an example of a BWP according to an embodiment of the present disclosure.

3A and 3B illustrate a radio protocol architecture for SL communication, according to an embodiment of the present disclosure.

4 illustrates a synchronization source or synchronization reference of V2X, according to an embodiment of the present disclosure.

5A and 5B illustrate a procedure for a terminal to perform V2X or SL communication according to a transmission mode, according to an embodiment of the present disclosure.

6A to 6C illustrate three cast types according to an embodiment of the present disclosure.

7 illustrates a resource unit for CBR measurement according to an embodiment of the present disclosure.

8 illustrates an example of an architecture in a 5G system in which positioning of a UE connected to a Next Generation-Radio Access Network (NG-RAN) or E-UTRAN is possible, according to an embodiment of the present disclosure.

9 is a diagram related to an example of a beam management scheme.

10A and 10B are diagrams illustrating an example of a beam pairing procedure applicable to the present disclosure.

11 is a diagram illustrating an example of a beam pairing procedure applicable to the present disclosure.

12 is a diagram illustrating an example of a beam pairing procedure applicable to the present disclosure.

13 is a diagram illustrating a discovery signal transmission scenario applicable to the present disclosure.

14 is a diagram illustrating an example of a discovery signal applicable to the present disclosure.

15 is a diagram illustrating an example of a discovery signal applicable to the present disclosure.

16 is a diagram illustrating an example of a discovery signal transmission method applicable to the present disclosure.

17A and 17B are diagrams illustrating examples of discovery signal transmission applicable to the present disclosure.

18 is a diagram illustrating an example of a transmitting terminal procedure applicable to the present disclosure.

19 is a diagram illustrating an example of a receiving terminal procedure applicable to the present disclosure.

20 is a diagram illustrating an example of beam sweeping applicable to the present disclosure.

21 is a diagram illustrating an example of sidelink synchronization signal transmission applicable to the present disclosure.

22 is a diagram illustrating an example of a symbol structure applicable to the present disclosure.

23 is a diagram illustrating an example of synchronization signal block transmission applicable to the present disclosure.

24 is a diagram illustrating an example of an S-SSB transmission method applicable to the present disclosure.

25 is a diagram illustrating an example of an S-SSB transmission method applicable to the present disclosure.

26 shows an example of a communication system, according to an embodiment of the present disclosure.

27 illustrates an example of a wireless device, according to an embodiment of the present disclosure.

28 illustrates an example of a vehicle or autonomous driving vehicle, according to an embodiment of the present disclosure.

The following embodiments combine elements and features of the present disclosure in a predetermined form. Each component or feature may be considered optional unless explicitly stated otherwise. Each component or feature may be implemented in a form that is not combined with other components or features. In addition, some components and/or features may be combined to configure an embodiment of the present disclosure. The order of operations described in embodiments of the present disclosure may be changed. Some configurations or features of one embodiment may be included in other embodiments, or may be replaced with corresponding configurations or features of other embodiments.

In the description of the drawings, procedures or steps that may obscure the gist of the present disclosure are not described, and procedures or steps that can be understood at the level of a person skilled in the art are also not described.

Throughout the specification, when a part is said to "comprising or including" a certain component, it does not exclude other components unless otherwise stated, meaning that other components may be further included. do. In addition, terms such as “…unit”, “…group”, and “module” described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software or a combination of hardware and software. have. Also, "a or an", "one", "the" and like related terms are used differently herein in the context of describing the present disclosure (especially in the context of the following claims). Unless indicated or clearly contradicted by context, it may be used in a sense including both the singular and the plural.

In this specification, "A or B (A or B)" may mean "only A", "only B", or "both A and B". In other words, in the present specification, "A or B (A or B)" may be interpreted as "A and/or B (A and/or B)". For example, "A, B or C(A, B or C)" herein means "only A", "only B", "only C", or "any and any combination of A, B and C ( any combination of A, B and C)".

As used herein, a slash (/) or a comma (comma) may mean “and/or”. For example, “A/B” may mean “A and/or B”. Accordingly, “A/B” may mean “only A”, “only B”, or “both A and B”. For example, “A, B, C” may mean “A, B, or C”.

As used herein, “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" means "at least one It can be interpreted the same as "A and B (at least one of A and B)".

Also, as used herein, "at least one of A, B and C" means "only A", "only B", "only C", or "A, B and C" any combination of A, B and C". Also, "at least one of A, B or C" or "at least one of A, B and/or C" means can mean “at least one of A, B and C”.

In addition, parentheses used herein may mean "for example". Specifically, when displayed as “control information (PDCCH)”, “PDCCH” may be proposed as an example of “control information”. In other words, "control information" in the present specification is not limited to "PDCCH", and "PDDCH" may be proposed as an example of "control information". Also, even when displayed as “control information (ie, PDCCH)”, “PDCCH” may be proposed as an example of “control information”.

In the following description, 'when, if, in case of' may be replaced with 'based on/based on'.

In this specification, technical features that are individually described within one drawing may be implemented individually or simultaneously.

In the present specification, a higher layer parameter may be set for the terminal, preset, or a predefined parameter. For example, the base station or the network may transmit higher layer parameters to the terminal. For example, the higher layer parameter may be transmitted through radio resource control (RRC) signaling or medium access control (MAC) signaling.

The following technologies include 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. It can be used in various wireless communication systems. CDMA may be implemented with a radio technology such as universal terrestrial radio access (UTRA) or CDMA2000. TDMA may be implemented with a radio technology such as global system for mobile communications (GSM)/general packet radio service (GPRS)/enhanced data rates for GSM evolution (EDGE). OFDMA may be implemented with a wireless technology such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and evolved UTRA (E-UTRA). IEEE 802.16m is an evolution of IEEE 802.16e, and provides backward compatibility with a system 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 a part of evolved UMTS (E-UMTS) that uses evolved-UMTS terrestrial radio access (E-UTRA), and employs OFDMA in the downlink and SC in the uplink. - Adopt FDMA. LTE-A (advanced) is an evolution of 3GPP LTE.

5G NR is a successor technology of LTE-A, and is a new clean-slate type mobile communication system with characteristics such as high performance, low latency, and high availability. 5G NR can utilize all available spectrum resources, from low frequency bands below 1 GHz, to intermediate frequency bands from 1 GHz to 10 GHz, and high frequency (millimeter wave) bands above 24 GHz.

For clarity of explanation, 5G NR is mainly described, but the technical idea according to an embodiment of the present disclosure is not limited thereto.

For terms and techniques not specifically described among terms and techniques used in this specification, reference may be made to a wireless communication standard document published before the present specification is filed. For example, the following document may be referred to.

(1) 3GPP LTE

- 3GPP TS 36.211: Physical channels and modulation

- 3GPP TS 36.212: Multiplexing and channel coding

- 3GPP TS 36.213: Physical layer procedures

- 3GPP TS 36.214: Physical layer; Measurements

- 3GPP TS 36.300: Overall description

- 3GPP TS 36.304: User Equipment (UE) procedures in idle mode

- 3GPP TS 36.314: Layer 2 - Measurements

- 3GPP TS 36.321: Medium Access Control (MAC) protocol

- 3GPP TS 36.322: Radio Link Control (RLC) protocol

- 3GPP TS 36.323: Packet Data Convergence Protocol (PDCP)

- 3GPP TS 36.331: Radio Resource Control (RRC) protocol

(2) 3GPP NR (e.g. 5G)

- 3GPP TS 38.211: Physical channels and modulation

- 3GPP TS 38.212: Multiplexing and channel coding

- 3GPP TS 38.213: Physical layer procedures for control

- 3GPP TS 38.214: Physical layer procedures for data

- 3GPP TS 38.215: Physical layer measurements

- 3GPP TS 38.300: Overall description

- 3GPP TS 38.304: User Equipment (UE) procedures in idle mode and in RRC inactive state

- 3GPP TS 38.321: Medium Access Control (MAC) protocol

- 3GPP TS 38.322: Radio Link Control (RLC) protocol

- 3GPP TS 38.323: Packet Data Convergence Protocol (PDCP)

- 3GPP TS 38.331: Radio Resource Control (RRC) protocol

- 3GPP TS 37.324: Service Data Adaptation Protocol (SDAP)

- 3GPP TS 37.340: Multi-connectivity; Overall description

Communication system applicable to the present disclosure

1 illustrates a structure of a wireless communication system according to an embodiment of the present disclosure. The embodiment of FIG. 1 may be combined with various embodiments of the present disclosure.

Referring to FIG. 1 , a wireless communication system includes a radio access network (RAN) 102 and a core network 103 . The radio access network 102 includes a base station 120 that provides a control plane and a user plane to a terminal 110 . The terminal 110 may be fixed or mobile, and includes a user equipment (UE), a mobile station (MS), a subscriber station (SS), a mobile subscriber station (MSS), It may be called another term such as a mobile terminal, an advanced mobile station (AMS), or a wireless device. The base station 120 means a node that provides a radio access service to the terminal 110, and a fixed station, Node B, eNB (eNode B), gNB (gNode B), ng-eNB, advanced base station (advanced station) It may be referred to as a base station (ABS) or other terms such as an access point, a base tansceiver system (BTS), or an access point (AP). The core network 103 includes a core network entity 130 . The core network entity 130 may be defined in various ways according to functions, and may be referred to as other terms such as a core network node, a network node, and a network equipment.

Components of a system may be referred to differently according to applied system standards. In the case of LTE or LTE-A standard, the radio access network 102 may be referred to as an Evolved-UMTS Terrestrial Radio Access Network (E-UTRAN), and the core network 103 may be referred to as an evolved packet core (EPC). In this case, the core network 103 includes a Mobility Management Entity (MME), a Serving Gateway (S-GW), and a packet data network-gateway (P-GW). The MME has access information of the terminal or information about the capability of the terminal, and this information is mainly used for mobility management of the terminal. The S-GW is a gateway having E-UTRAN as an endpoint, and the P-GW is a gateway having a packet data network (PDN) as an endpoint.

In the case of the 5G NR standard, the radio access network 102 may be referred to as NG-RAN, and the core network 103 may be referred to as 5GC (5G core). In this case, the core network 103 includes an access and mobility management function (AMF), a user plane function (UPF), and a session management function (SMF). The AMF provides a function for access and mobility management in units of terminals, the UPF performs a function of mutually transferring data units between the upper data network and the wireless access network 102, and the SMF provides a session management function.

The base stations 120 may be connected to each other through an Xn interface. The base station 120 may be connected to the core network 103 through an NG interface. More specifically, the base station 130 may be connected to the AMF through the NG-C interface, may be connected to the UPF through the NG-U interface.

2 illustrates an example of a bandwidth part (BWP) according to an embodiment of the present disclosure. The embodiment of FIG. 2 may be combined with various embodiments of the present disclosure. In the embodiment of FIG. 2 , it is assumed that there are three BWPs.

Referring to FIG. 2 , a common resource block (CRB) may be a numbered carrier resource block from one end to the other end of a carrier band. And, the PRB may be a numbered resource block within each BWP. Point A may indicate a common reference point for a resource block grid (resource block grid).

BWP may be set by a point A, an offset from the point A (N ^start _BWP ), and a bandwidth (N ^size _BWP ). For example, the point A may be an external reference point of the PRB of the carrier to which subcarrier 0 of all neumonologies (eg, all neumannologies supported by the network in that carrier) is aligned. For example, the offset may be the PRB spacing between point A and the lowest subcarrier in a given numerology. For example, the bandwidth may be the number of PRBs in a given neurology.

V2X or sidelink (SL) communication

3A and 3B illustrate a radio protocol architecture for SL communication, according to an embodiment of the present disclosure. 3A and 3B may be combined with various embodiments of the present disclosure. Specifically, FIG. 3A shows a user plane protocol stack, and FIG. 3B illustrates a control plane protocol stack.

SL Synchronization Signal (SLSS) and Synchronization Information

The SLSS is an SL-specific sequence and may include a Primary Sidelink Synchronization Signal (PSSS) and a Secondary Sidelink Synchronization Signal (SSSS). 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, length-127 M-sequences may be used for S-PSS, and length-127 Gold sequences may be used for S-SSS. . For example, the terminal may detect an initial signal using S-PSS and may obtain synchronization. For example, the UE may acquire detailed synchronization using S-PSS and S-SSS, and may detect a synchronization signal ID.

PSBCH (Physical Sidelink Broadcast Channel) may be a (broadcast) channel through which basic (system) information that the UE needs to know first before transmission and reception of an SL signal is transmitted. For example, the basic information is information related to SLSS, duplex mode (Duplex Mode, DM), TDD UL/DL (Time Division Duplex Uplink/Downlink) configuration, resource pool related information, type of application related to SLSS, It may be a subframe offset, broadcast information, or the like. For example, for evaluation of PSBCH performance, in NR V2X, the payload size of PSBCH may be 56 bits including a CRC of 24 bits.

S-PSS, S-SSS, and PSBCH may be included in a block format supporting periodic transmission (eg, SL SS (Synchronization Signal)/PSBCH block, hereinafter S-SSB (Sidelink-Synchronization Signal Block)). The S-SSB may have the same numerology (ie, SCS and CP length) as a Physical Sidelink Control Channel (PSCCH)/Physical Sidelink Shared Channel (PSSCH) in the carrier, and the transmission bandwidth is (pre)set SL Sidelink (BWP) BWP). For example, the bandwidth of the S-SSB may be 11 resource blocks (RBs). For example, the PSBCH may span 11 RBs. And, the frequency position of the S-SSB may be set (in advance). Therefore, the UE does not need to perform hysteresis detection in the frequency to discover the S-SSB in the carrier.

For example, based on Table 1, the UE may generate an S-SS/PSBCH block (ie, S-SSB), and the UE may generate an S-SS/PSBCH block (ie, S-SSB) on a physical resource. can be mapped to and transmitted.

Acquisition of synchronization of SL terminal

In time division multiple access (TDMA) and frequency division multiples access (FDMA) systems, accurate time and frequency synchronization is essential. If time and frequency synchronization is not accurately performed, system performance may be degraded due to Inter Symbol Interference (ISI) and Inter Carrier Interference (ICI). This is the same in V2X. For time/frequency synchronization in V2X, a SL synchronization signal (sidelink synchronization signal, SLSS) can be used in the physical layer, and MIB-SL-V2X (master information block-sidelink-V2X) in the RLC (radio link control) layer can be used

4 illustrates a synchronization source or synchronization reference of V2X, according to an embodiment of the present disclosure. The embodiment of FIG. 4 may be combined with various embodiments of the present disclosure.

Referring to Figure 4, in V2X, the terminal is directly synchronized to GNSS (global navigation satellite systems), or indirectly synchronized to the GNSS through the terminal (in network coverage or out of network coverage) synchronized to the GNSS. can When the GNSS is set as the synchronization source, the UE may calculate the DFN and the subframe number using Coordinated Universal Time (UTC) and a (pre)set Direct Frame Number (DFN) offset.

Alternatively, the terminal may be directly synchronized with the base station or may be synchronized with another terminal synchronized with the base station in time/frequency. For example, the base station may be an eNB or a gNB. For example, when the terminal is within network coverage, the terminal may receive synchronization information provided by the base station and may be directly synchronized with the base station. Thereafter, the terminal may provide synchronization information to other adjacent terminals. When the base station timing is set as the synchronization reference, the terminal is a cell (if within cell coverage at the frequency), primary cell or serving cell (when out of cell coverage at the frequency) associated with the frequency for synchronization and downlink measurement ) can be followed.

A base station (eg, a serving cell) may provide a synchronization setting for a carrier used for V2X or SL communication. In this case, the terminal may follow the synchronization setting received from the base station. If the terminal does not detect any cell in the carrier used for the V2X or SL communication and does not receive a synchronization setting from the serving cell, the terminal may follow the preset synchronization setting.

Alternatively, the terminal may be synchronized with another terminal that has not obtained synchronization information directly or indirectly from the base station or GNSS. The synchronization source and preference may be preset in the terminal. Alternatively, the synchronization source and preference may be set through a control message provided by the base station.

The SL synchronization source may be associated with a synchronization priority. For example, the relationship between the synchronization source and the synchronization priority may be defined as in Table 2 or Table 3. Table 2 or Table 3 is only an example, and the relationship between the synchronization source and the synchronization priority may be defined in various forms.

priority
ranking
level Synchronization based on GNSS
(GNSS-based synchronization) Base station-based synchronization
(eNB/gNB-based synchronization) P0 GNSS base station P1 All terminals synchronized directly to GNSS All terminals directly synchronized to the base station P2 All terminals indirectly synchronized to GNSS All terminals indirectly synchronized to the base station P3 all other terminals GNSS P4 N/A All terminals synchronized directly to GNSS P5 N/A All terminals indirectly synchronized to GNSS P6 N/A all other terminals

priority
ranking
level Synchronization based on GNSS
(GNSS-based synchronization) Base station-based synchronization
(eNB/gNB-based synchronization) P0 GNSS base station P1 All terminals synchronized directly to GNSS All terminals directly synchronized to the base station P2 All terminals indirectly synchronized to GNSS All terminals indirectly synchronized to the base station P3 base station GNSS P4 All terminals directly synchronized to the base station All terminals synchronized directly to GNSS P5 All terminals indirectly synchronized to the base station All terminals indirectly synchronized to GNSS P6 Remaining terminal(s) with low priority Remaining terminal(s) with low priority

In Table 2 or Table 3, P0 may mean the highest priority, and P6 may mean the lowest priority. In Table 2 or Table 3, a base station may include at least one of a gNB or an eNB.

Whether to use GNSS-based synchronization or base station-based synchronization may be set (in advance). In single-carrier operation, the UE may derive the transmission timing of the UE from the available synchronization criterion having the highest priority.

For example, the terminal may (re)select a synchronization reference, and the terminal may acquire synchronization from the synchronization reference. In addition, the UE may perform SL communication (eg, PSCCH/PSSCH transmission/reception, Physical Sidelink Feedback Channel (PSFCH) transmission/reception, S-SSB transmission/reception, reference signal transmission/reception, etc.) based on the obtained synchronization.

5A and 5B illustrate a procedure for a terminal to perform V2X or SL communication according to a transmission mode, according to an embodiment of the present disclosure. 5A and 5B may be combined with various embodiments of the present disclosure. In various embodiments of the present disclosure, the transmission mode may be referred to as a mode or a resource allocation mode. Hereinafter, for convenience of description, a transmission mode in LTE may be referred to as an LTE transmission mode, and a transmission mode in NR may be referred to as an NR resource allocation mode.

For example, FIG. 5A illustrates a terminal operation related to LTE transmission mode 1 or LTE transmission mode 3 . Or, for example, FIG. 5A illustrates a terminal operation related to NR resource allocation mode 1. For example, LTE transmission mode 1 may be applied to general SL communication, and LTE transmission mode 3 may be applied to V2X communication.

For example, FIG. 5B illustrates a terminal operation related to LTE transmission mode 2 or LTE transmission mode 4. Or, for example, FIG. 5B illustrates a terminal operation related to NR resource allocation mode 2.

Referring to FIG. 5A , in LTE transmission mode 1, LTE transmission mode 3, or NR resource allocation mode 1, the base station may schedule an SL resource to be used by the terminal for SL transmission. For example, the base station may transmit information related to SL resources and/or information related to UL resources to the first terminal. For example, the UL resource may include a PUCCH resource and/or a PUSCH resource. For example, the UL resource may be a resource for reporting SL HARQ feedback to the base station.

For example, the first terminal may receive information related to a dynamic grant (DG) resource and/or information related to a configured grant (CG) resource from the base station. For example, the CG resource may include a CG type 1 resource or a CG type 2 resource. In this specification, the DG resource may be a resource configured/allocated by the base station to the first terminal through downlink control information (DCI). In this specification, the CG resource may be a (periodic) resource configured/allocated by the base station to the first terminal through DCI and/or RRC messages. For example, in the case of a CG type 1 resource, the base station may transmit an RRC message including information related to the CG resource to the first terminal. For example, in the case of a CG type 2 resource, the base station may transmit an RRC message including information related to the CG resource to the first terminal, and the base station transmits DCI related to activation or release of the CG resource. It can be transmitted to the first terminal.

Subsequently, the first terminal may transmit a PSCCH (eg, sidelink control information (SCI) or 1 ^st- stage SCI) to the second terminal based on the resource scheduling. Thereafter, the first terminal may transmit a PSSCH (eg, 2 ^nd -stage SCI, MAC PDU, data, etc.) related to the PSCCH to the second terminal. Thereafter, the first terminal may receive the PSFCH related to the PSCCH/PSSCH from the second terminal. For example, HARQ feedback information (eg, NACK information or ACK information) may be received from the second terminal through the PSFCH. Thereafter, the first terminal may transmit/report the HARQ feedback information to the base station through PUCCH or PUSCH. For example, the HARQ feedback information reported to the base station may be information generated by the first terminal based on HARQ feedback information received from the second terminal. For example, the HARQ feedback information reported to the base station may be information generated by the first terminal based on a preset rule. For example, the DCI may be a DCI for scheduling of an SL. For example, the format of the DCI may be DCI format 3_0 or DCI format 3_1. Table 4 shows an example of DCI for SL scheduling.

3GPP TS 38.212

Referring to FIG. 5B , in LTE transmission mode 2, LTE transmission mode 4 or NR resource allocation mode 2, the UE may determine an SL transmission resource within an SL resource configured by a base station/network or a preset SL resource. For example, the configured SL resource or the preset SL resource may be a resource pool. For example, the UE may autonomously select or schedule a resource for SL transmission. For example, the UE may perform SL communication by selecting a resource by itself within a set resource pool. For example, the terminal may select a resource by itself within the selection window by performing a sensing (sensing) and resource (re)selection procedure. For example, the sensing may be performed in units of subchannels. For example, the first terminal select the resource itself in the resource pool PSCCH by using the resources (e.g., SCI (Sidelink Control Information) or the 1 ^st -stage SCI) may be transmitted to the second terminal. Subsequently, the first terminal may transmit a PSSCH (eg, 2 ^nd -stage SCI, MAC PDU, data, etc.) related to the PSCCH to the second terminal. Thereafter, the first terminal may receive the PSFCH related to the PSCCH/PSSCH from the second terminal.

Referring to FIG. 5A or FIG. 5B , for example, a first terminal may transmit an SCI to a second terminal on a PSCCH. Or, for example, the first terminal may transmit two consecutive SCIs (eg, 2-stage SCI) to the second terminal on the PSCCH and/or the PSSCH. In this case, the second terminal may decode two consecutive SCIs (eg, 2-stage SCI) to receive the PSSCH from the first terminal. Herein, SCI is transmitted on PSCCH 1 ^st SCI, SCI claim 1, 1 may be called ^st -stage SCI or SCI format 1 ^st -stage, SCI transmitted on the 2 ^nd PSSCH SCI, SCI Claim 2, 2 It can be called ^nd -stage SCI or 2 ^nd -stage SCI format. For example, 1 ^st -stage SCI format may include SCI format 1-A, and 2 ^nd -stage SCI format may include SCI format 2-A and/or SCI format 2-B.

5A or 5B , the first terminal may receive the PSFCH. For example, the first terminal and the second terminal may determine the PSFCH resource, and the second terminal may transmit the HARQ feedback to the first terminal using the PSFCH resource.

Referring to FIG. 5A , the first terminal may transmit SL HARQ feedback to the base station through PUCCH and/or PUSCH.

6A to 6C illustrate three cast types according to an embodiment of the present disclosure. 6A to 6C may be combined with various embodiments of the present disclosure.

Specifically, FIG. 6A illustrates SL communication of a broadcast type, FIG. 6B illustrates SL communication of a unicast type, and FIG. 6C illustrates SL communication of a groupcast type. In the case of unicast type SL communication, the terminal may perform one-to-one communication with another terminal. In the case of groupcast type SL communication, the terminal may perform SL communication with one or more terminals in a group to which the terminal belongs. In various embodiments of the present disclosure, SL groupcast communication may be replaced with SL multicast communication, SL one-to-many communication, or the like.

Hybrid Automatic Repeat Request (HARQ) procedure

SL HARQ feedback may be enabled for unicast. In this case, in a non-Code Block Group (non-CBG) operation, when the receiving terminal decodes the PSCCH targeting the receiving terminal, and the receiving terminal successfully decodes the transport block related to the PSCCH, the receiving terminal HARQ-ACK may be generated. And, the receiving terminal may transmit the HARQ-ACK to the transmitting terminal. On the other hand, if the receiving terminal does not successfully decode the transport block related to the PSCCH after the receiving terminal decodes the PSCCH targeting the receiving terminal, the receiving terminal may generate a HARQ-NACK. And, the receiving terminal may transmit the HARQ-NACK to the transmitting terminal.

For example, SL HARQ feedback may be enabled for groupcast. For example, in non-CBG operation, two HARQ feedback options may be supported for groupcast.

(1) Groupcast option 1: After the receiving terminal decodes the PSCCH targeting the receiving terminal, if the receiving terminal fails to decode the transport block related to the PSCCH, the receiving terminal transmits the HARQ-NACK through the PSFCH It can be transmitted to the transmitting terminal. On the other hand, if the receiving terminal decodes the PSCCH targeting the receiving terminal, and the receiving terminal successfully decodes the transport block related to the PSCCH, the receiving terminal may not transmit the HARQ-ACK to the transmitting terminal.

(2) groupcast option 2: If the receiving terminal fails to decode a transport block related to the PSCCH after the receiving terminal decodes the PSCCH targeting the receiving terminal, the receiving terminal transmits a HARQ-NACK through the PSFCH It can be transmitted to the transmitting terminal. And, when the receiving terminal decodes the PSCCH targeted to the receiving terminal, and the receiving terminal successfully decodes the transport block related to the PSCCH, the receiving terminal may transmit a HARQ-ACK to the transmitting terminal through the PSFCH.

For example, if groupcast option 1 is used for SL HARQ feedback, all terminals performing groupcast communication may share a PSFCH resource. For example, terminals belonging to the same group may transmit HARQ feedback using the same PSFCH resource.

For example, if groupcast option 2 is used for SL HARQ feedback, each terminal performing groupcast communication may use different PSFCH resources for HARQ feedback transmission. For example, terminals belonging to the same group may transmit HARQ feedback using different PSFCH resources.

In this specification, HARQ-ACK may be referred to as ACK, ACK information, or positive-ACK information, and HARQ-NACK may be referred to as NACK, NACK information, or negative-ACK information.

SL measurement and reporting

For the purpose of QoS prediction, initial transmission parameter setting, link adaptation, link management, admission control, etc., SL measurement and reporting between terminals (eg For example, RSRP, RSRQ) may be considered in SL. For example, the receiving terminal may receive a reference signal from the transmitting terminal, and the receiving terminal may measure a channel state for the transmitting terminal based on the reference signal. In addition, the receiving terminal may report channel state information (CSI) to the transmitting terminal. SL-related measurement and reporting may include measurement and reporting of CBR, and reporting of location information. Examples of CSI (Channel Status Information) for V2X are CQI (Channel Quality Indicator), PMI (Precoding Matrix Index), RI (Rank Indicator), RSRP (Reference Signal Received Power), RSRQ (Reference Signal Received Quality), path gain (pathgain)/pathloss, SRI (Sounding Reference Symbols, Resource Indicator), CRI (CSI-RS Resource Indicator), interference condition, vehicle motion, and the like. CSI reporting may be activated and deactivated according to settings.

For example, the transmitting terminal may transmit a CSI-RS to the receiving terminal, and the receiving terminal may measure CQI or RI by using the CSI-RS. For example, the CSI-RS may be referred to as an SL CSI-RS. For example, the CSI-RS may be confined within PSSCH transmission. For example, the transmitting terminal may transmit the CSI-RS to the receiving terminal by including the CSI-RS on the PSSCH resource.

SL sidelink congestion control

For example, the terminal determines whether the energy measured in the unit time/frequency resource is above a certain level, and determines the amount and frequency of its transmission resource according to the ratio of the unit time/frequency resource in which the energy of the predetermined level or more is observed. can be adjusted In the present specification, a ratio of time/frequency resources in which energy of a certain level or higher is observed may be defined as a channel congestion ratio (CBR). The UE may measure CBR for a channel/frequency. Additionally, the UE may transmit the measured CBR to the network/base station.

7 illustrates a resource unit for CBR measurement according to an embodiment of the present disclosure. The embodiment of FIG. 7 may be combined with various embodiments of the present disclosure.

Referring to FIG. 7 , as a result of the UE measuring a Received Signal Strength Indicator (RSSI) in units of subchannels for a specific period (eg, 100 ms) for a specific period (eg, 100 ms), the CBR is a sub having a value greater than or equal to a preset threshold. It may mean the number of channels. Alternatively, the CBR may mean a ratio of subchannels having a value greater than or equal to a preset threshold among subchannels during a specific period. For example, if it is assumed that the hatched subchannels of FIG. 7 are subchannels having a value greater than or equal to a preset threshold, CBR may mean the ratio of the hatched subchannels for a period of 100 ms. Additionally, the terminal may report the CBR to the base station.

For example, when the PSCCH and the PSSCH are multiplexed in the frequency domain, the UE may perform one CBR measurement for one resource pool. Here, if the PSFCH resource is configured or preset, the PSFCH resource may be excluded from the CBR measurement.

Furthermore, congestion control in consideration of the priority of traffic (eg, packets) may be required. To this end, for example, the terminal may measure a channel occupancy ratio (CR). Specifically, the terminal measures the CBR, and the terminal measures the maximum value (CRlimitk) of the channel occupancy Ratio k (CRk) that the traffic corresponding to each priority (eg, k) can occupy according to the CBR. ) can be determined. For example, the terminal may derive the maximum value (CRlimitk) of the channel occupancy for each traffic priority based on a predetermined table of CBR measurement values. For example, in the case of traffic having a relatively high priority, the terminal may derive a maximum value of a relatively large channel occupancy. Thereafter, the terminal may perform congestion control by limiting the sum of the channel occupancy rates of traffic having a priority k of traffic lower than i to a predetermined value or less. According to this method, a stronger channel occupancy limit may be applied to traffic having a relatively low priority.

In addition, the UE may perform SL congestion control by using methods such as adjusting the size of transmission power, dropping packets, determining whether to retransmit, and adjusting the size of the transmission RB (MCS adjustment).

An example of SL CBR and SL RSSI is as follows. In the description below, the slot index may be based on a physical slot index.

The SL CBR measured in slot n is the portion of subchannels in which the SL RSSI measured by the UE in the resource pool, sensed over the CBR measurement window [na, n-1], exceeds a (pre)set threshold. is defined as Here, according to the upper layer parameter timeWindowSize-CBR, a is equal to ^{100 or 100·2 μ slots.} SL CBR may be applied to RRC_IDLE intra-frequency, RRC_IDLE inter-frequency, RRC_CONNECTED intra-frequency, and RRC_CONNECTED inter-frequency.

SL RSSI is defined as a linear average of the total received power (in [W]) observed in subchannels configured in OFDM symbols of slots configured for PSCCH and PSSCH starting from the second OFDM symbol. For FR1, the reference point for SL RSSI will be the antenna connector of the UE. For FR2, the SL RSSI will be measured based on the combined signal from the antenna elements corresponding to the given receiver branch. For FR1 and FR2, if receive diversity is used by the UE, the reported SL RSSI value shall not be less than the corresponding SL RSSI of any of the individual receiver branches. The SL RSSI may be applied to RRC_IDLE intra-frequency, RRC_IDLE inter-frequency, RRC_CONNECTED intra-frequency, and RRC_CONNECTED inter-frequency.

An example of an SL CR (Channel Occupancy Ratio) is as follows. The SL CR evaluated in slot n is the total number of subchannels used for transmission in slot [na, n-1] and granted in slot [n, n+b] in slot [na, n] +b] divided by the total number of configured subchannels in the transmission pool. SL CR may be applied to RRC_IDLE intra-frequency, RRC_IDLE inter-frequency, RRC_CONNECTED intra-frequency, and RRC_CONNECTED inter-frequency. Here, a may be a positive integer, b may be 0, or a may be a positive integer. a and b are determined by the UE implementation, and may be a+b+1=1000 or a+b+1=1000·2 ^μ according to the upper layer parameter timeWindowSize-CBR. b < (a+b+1)/2, and n+b shall not exceed the last transmission opportunity of a grant for current transmission. SL CR is evaluated for each (re)transmission. In evaluating the SL CR, according to the grant(s) present in slot [n+1, n+b] without packet dropping, the UE will assume that the transmission parameter used in slot n is reused. The slot index may be a physical slot index. SL CR may be calculated for each priority level. If it is a member of the established sidelink grant defined in TS 38.321, the resource is treated as granted.

positioning

8 illustrates an example of an architecture in a 5G system in which positioning of a UE connected to a Next Generation-Radio Access Network (NG-RAN) or E-UTRAN is possible, according to an embodiment of the present disclosure.

Referring to FIG. 8 , the AMF receives a request for a location service related to a specific target UE from another entity such as a Gateway Mobile Location Center (GMLC), or the AMF itself starts a location service on behalf of a specific target UE. may decide to Then, the AMF may transmit a location service request to a Location Management Function (LMF). Upon receiving the location service request, the LMF may process the location service request and return a processing result including the estimated location of the UE to the AMF. Meanwhile, when the location service request is received from another entity, such as GMLC, other than the AMF, the AMF may transmit the processing result received from the LMF to the other entity.

New generation evolved-NB (ng-eNB) and gNB are network elements of NG-RAN that can provide a measurement result for location estimation, and can measure a radio signal for a target UE and deliver the result to the LMF. . In addition, the ng-eNB may control some TPs (Transmission Points) such as remote radio heads or PRS-only TPs supporting a Positioning Reference Signal (PRS) based beacon system for E-UTRA.

The LMF is connected to an Enhanced Serving Mobile Location Center (E-SMLC), and the E-SMLC may enable the LMF to access the E-UTRAN. For example, the E-SMLC uses a downlink measurement obtained by the target UE through a signal transmitted from the LMF eNB and/or PRS-dedicated TPs in the E-UTRAN to OTDOA, which is one of the positioning methods of the E-UTRAN. (Observed Time Difference Of Arrival) can be supported.

Meanwhile, the LMF may be connected to a SUPL Location Platform (SLP). The LMF may support and manage different location services for target UEs. The LMF may interact with the serving ng-eNB or serving gNB for the target UE to obtain the UE's location measurement. For positioning of the target UE, the LMF is a Location Service (LCS) client type, required Quality of Service (QoS), UE positioning capabilities, gNB positioning capabilities and ng-eNB positioning capabilities based on a positioning method, etc. and may apply this positioning method to the serving gNB and/or the serving ng-eNB. Then, the LMF may determine a position estimate for the target UE and additional information such as accuracy of the position estimate and velocity. The SLP is a SUPL (Secure User Plane Location) entity responsible for positioning through a user plane.

UE downlinks through sources such as NG-RAN and E-UTRAN, different Global Navigation Satellite System (GNSS), Terrestrial Beacon System (TBS), Wireless Local Access Network (WLAN) access point, Bluetooth beacon and UE barometric pressure sensor, etc. Link signal can be measured. The UE may include the LCS application, and may access the LCS application through communication with a network to which the UE is connected or other applications included in the UE. The LCS application may include measurement and calculation functions necessary to determine the location of the UE. For example, the UE may include an independent positioning function such as Global Positioning System (GPS), and may report the location of the UE independently of NG-RAN transmission. The independently acquired positioning information may be utilized as auxiliary information of positioning information acquired from the network.

Specific embodiments of the present disclosure

A vehicle supporting the mmWave V2X (vehicle to everything) communication system must use a directional transmit/receive beam to overcome signal attenuation due to high frequency characteristics. Terms such as automobile, vehicle, and terminal may be used interchangeably herein. In order for the terminal to transmit/receive a signal through the directional transmission/reception beam, the directional beams between the transmitting terminal and the receiving terminal must match. In order for the terminal to match the directional beam with another terminal, a process of selecting a beam optimized for signal transmission and reception by measuring signal strengths for all directional beams formed by the terminal may be required. This process guarantees a high antenna gain and can guarantee reception quality. However, in order for the terminal to obtain a high gain, the beam width should be as small as possible. A blockage problem may occur due to a small beam width. Blockage may increase a beam sweeping time, and may increase a transmit and receive beam alignment (Tx/Rx beam alignment) time.

The present disclosure is aperiodic (aperiodic) channel state information-reference signal (channel state information-reference signal, CSI-RS) reporting (reporting) or channel state information (channel state information, CSI) through the most recent beam report (latest beam reporting) is proposed. According to the present disclosure, the problem of blockage between vehicles frequently occurring on the road can be solved. In addition, according to the present disclosure, in the mmWave V2X communication system, the time taken for beam alignment can be reduced. Accordingly, communication delay can be reduced. In this specification, Tx may mean transmission and Rx may mean reception, respectively.

9 is a diagram related to an example of a beam management scheme. The receiving terminal may select an optimal beam pair through beam sweeping during a set beam management window duration. The receiving terminal may report the optimal beam pair to the transmitting terminal. Since the beam report is performed before a beam pair between transmission and reception is established, the beam report can be reported using a sidelink. This method may increase the beam sweeping time. In addition, the transmit and receive beam alignment times may be increased. The present disclosure proposes a method for quickly finding an optimal beam pair between transmitting and receiving terminals for solving the blockage problem of beam management (BM) in an mmWave communication system.

10A and 10B are diagrams illustrating an example of a beam pairing procedure applicable to the present disclosure. In the present disclosure, when two vehicles perform beam management, a latest best beam pair may exist between beam pairs. The two vehicles may determine that blockage occurs when the most recent optimal beam pair exists between the beam pairs. In this case, the latest beam reporting may be performed through aperiodic CSI-RS reporting or CSI reporting.

Referring to the upper part of FIG. 10A , vehicle A 1002 and vehicle B 1004 may be connected to each other. As an example, the two vehicles may be connected to each other via beam a-4 of vehicle A 1002 and beam b-4 of vehicle B 1004 . Also, beam a-4 of vehicle A 1002 and beam b-4 of vehicle B 1004 may have a light of sight (LOS) relationship. That is, the vehicle A 1002 and the vehicle B 1004 are connected to the LOS beam through mmWave beam management to perform communication. Vehicle C 1006 has not yet caused a blockage problem with respect to communication between vehicle A 1002 and vehicle B 1004 .

Referring to the lower part of FIG. 10A , when vehicle A 1002 and vehicle B 1004 perform beam management, vehicle C 1006 is causing a blockage problem. Beam a-4 of vehicle A 1002 and beam b-4 of vehicle B 1004 may be blocked. Accordingly, vehicle A and vehicle B may be connected through a beam having the strongest signal after blocking. As an example, beam a-2 of vehicle A 1002 and beam b-2 of vehicle B 1004 may be connected through beam management. Vehicle B (1004) can be measured as the beam a-6 a 2 (signal noise ratio) ^nd SNR of its beam b-6 and charang A (1002). Vehicle B 1004 may determine that blockage occurs between vehicle A 1002 and vehicle B 1004 through this measurement. After vehicle B determines that blockage occurs between vehicle A and itself, vehicle B reports the latest beam through an aperiodic CSI-RS report or CSI report for fast beam pairing. beam reporting) can be performed. That is, vehicle B determines that blockage occurs between vehicle A and itself, and then through an aperiodic CSI-RS report or CSI report for beam pairing regarding the a-4 beam of vehicle A and the b-4 beam of vehicle B. The most recent beam report may be transmitted to vehicle A.

10B is a diagram illustrating an example of a beam pairing procedure applicable to the present disclosure. Referring to the upper part of FIG. 10B , it may represent a case in which the blockage generated in FIG. 10A disappears. That is, it may represent a case where vehicle C 1006 disappears between vehicle A 1002 and vehicle B 1004 . The situation indicated by the upper end of FIG. 10B may occur subsequent to the situation indicated by FIG. 10 . Referring to the procedure of FIG. 10A , vehicle A may receive the latest beam reporting from vehicle B. Accordingly, the vehicle A may perform fast beam pairing with the a-4 beam of the vehicle A and the b-4 beam of the vehicle B after the vehicle C disappears. The vehicle A may be connected to the vehicle B by performing beam pairing using the a-4 beam of the vehicle A and the b-4 beam of the vehicle B.

11 is a diagram illustrating an example of a beam pairing procedure applicable to the present disclosure. In step S1101, the transmitting terminal 1102 may request a CSI-RS from the receiving terminal 1104. For example, the transmitting terminal 1102 may request a CSI-RS from the receiving terminal 1104 through a physical sidelink control channel (PSCCH). In step S1103, the receiving terminal 1104 may transmit a CSI-RS report to the transmitting terminal 1102. For example, the receiving terminal 1104 may transmit a CSI-RS report including the latest beam reporting to the transmitting terminal 1102 through the PSCCH.

More specifically, the transmitting terminal 1102 and the receiving terminal 1104 may be connected through LOS beam pairing. Blockage may occur between the transmitting terminal 1102 and the receiving terminal 1104 .

When blockage occurs, the transmitting terminal may be connected to the receiving terminal using beam pairing having the largest SNR by performing beam management. Also, the receiving terminal may measure beam pairing having the second largest SNR through beam management. The receiving terminal may determine that the most recent beam pairing is located between the beam pairing having the largest SNR and the beam pairing having the second largest SNR. The receiving terminal may determine that blockage has occurred when the most recent beam pairing is located between a beam pairing having the largest SNR among new beam pairings and a beam pairing having the second largest SNR among new beam pairings. The receiving terminal 1104 may aperiodically transmit the most recent beam report to the transmitting terminal according to the CSI-RS request of the transmitting terminal 1102 .

When the blockage disappears, the transmitting terminal may perform fast beam pairing based on the most recent beam report. Accordingly, the transmitting terminal 1102 can quickly connect to the receiving terminal 1104 .

12 shows an example of a beam pairing procedure applicable to the present disclosure. Referring to FIG. 12 , in step S1201, the terminal may determine the occurrence of blockage based on the signal strength. For example, blockage may occur between a terminal and another terminal connected to the terminal. The terminal may be connected to another terminal connected to it through LOS beam pairing through beam management. When blockage occurs, the terminal may be connected to another terminal through beam pairing having the largest SNR again through beam management. The UE may measure beam pairing having the second largest SNR through beam management. When the LOS beam pairing, which is the most recent beam pairing, is located between the beam pairing having the largest SNR and the beam pairing having the second largest SNR, the UE may determine that blockage has occurred.

In step S1203, the UE may transmit the most recent beam pairing report using the CSI-RS. After determining that blockage has occurred, the terminal may transmit the most recent beam pairing report to another terminal. The UE may transmit the most recent beam pairing report by using an aperiodic CSI-RS according to a CSI-RS request of another UE connected to the UE. For example, the UE may perform the most recent beam pairing report through the PSCCH using aperiodic CSI-RS in response to a CSI-RS request through the PSCCH of another UE connected to the UE.

In step S1205, after the blockage is resolved, the terminal may perform fast beam pairing based on the most recent beam pairing report. After the blockage is resolved, the terminal can connect with another terminal through the most recent beam pairing by performing beam management. The terminal does not measure the intensity of all beam pairs by performing beam tracking, and can efficiently connect with other terminals through the most recent beam pairing. More specifically, the UE may not perform beam tracking while alternately transmitting (Tx) or receiving (Rx) a beam. Accordingly, the terminal may efficiently connect to another terminal based on the most recent beam pairing without measuring the strength of all beam pairs.

13 is a diagram illustrating a discovery signal transmission scenario applicable to the present disclosure. NR (new radio) sidelink communication of the current specification version is based on a base station, a global navigation satellite system (GNSS) or a synchronization reference user equipment (SyncRef UE) in the initial synchronization stage time) and frequency synchronization may be performed. Here, the current specification version may mean 3GPP TS 38.211, TS 38.212, TS 38.213, TS 38.214, and TS 38.331 release 16 (release 16). In NR (new radio) sidelink communication, a link is set up by a procedure in which a terminal attempting data transmission transmits a link setup request message to a receiving terminal, and the receiving terminal transmits a response message to the transmitting terminal. can be The current specification version is defined only for the sub-6GHz sidelink, which does not require beamforming. Accordingly, the terminal can receive a link setup_request message or a response message without a special procedure regarding the beam. On the other hand, sub-6GHz sidelink communication transmitted in omni-direction and Otherwise, in mmWave sidelink communication, beamforming may be essential to overcome the high path loss of the mmWave frequency. Therefore, for the link setup procedure described above, it is necessary to precede beam alignment between the transmitting terminal and the receiving terminal. have.

The present disclosure defines a discovery signal transmitted to recognize a neighboring terminal before the terminal starts data transmission in mmWave sidelink communication. In addition, the present disclosure proposes a method in which a UE transmits a discovery signal by applying Tx beam sweeping. Referring to FIG. 13 , an initiating user equipment 1301 that wants to transmit data is transmitting a discovery signal to recognize neighboring terminals 1303 . Specifically, the terminal 1301 to transmit data may transmit a discovery signal by applying transmit beam sweeping.

Meanwhile, in mmWave V2X communication, an initiating user equipment may transmit a discovery signal to a neighboring terminal. Upon receiving the discovery signal, the UE may make an access request using a random access channel (RACH) signal. After performing a response to an access request with an initiating user equipment RACH response signal, connection setup may be performed. The present disclosure can reduce power consumption for a receiving terminal to detect a Tx beam ID by extending a function of a discovery signal. In addition, the present disclosure may allow a flexible transmit beam sweep form to be used.

Meanwhile, 3GPP TS 38.211 discloses a sidelink synchronization signal generation method (sub-6Ghz sidelink) as shown in Table 5 below.

3GPP TS 38.211

14 is a diagram illustrating an example of a discovery signal applicable to the present disclosure. Referring to FIG. 14 , the discovery signal 1401 may include a discovery message 1403 and a sync signal 1405 . The discovery message 1403 may include a UE ID and a service ID. The terminal ID may be an ID related to a source ID. The terminal ID may be an ID indicating which terminal it is. The service ID may be an ID related to a service to be provided by the terminal.

A sequence ID of the synchronization signal 1405 may be set as a Tx beam ID. The sequence ID may determine the transmission sequence of the synchronization signal. The sequence ID of the synchronization signal 1405 is defined to support the maximum number of transmission beams of the UE in the system. For example, when the maximum number of transmission beams is 64, the sequence ID may have a value of 0 to 63. Here, the transmission beam ID may be an ID indicating which beam among 64 beams.

In the synchronization signal included in the discovery signal, a sequence ID may be set as a Tx beam ID. In this case, the terminal power consumption may be reduced compared to the case where the discovery message includes the transmission beam ID. Specifically, since the UE can determine the Tx beam ID only by detecting the synchronization signal without decoding the discovery message, the power consumption of the UE can be reduced. When the synchronization signal sets the sequence ID as the Tx beam ID, the UE does not transmit Tx beam ID information and uses only a pre-defined Tx beam sweep form, compared to the case of using a flexible Tx beam. A sweep form can be used. Specifically, there is an effect that the UE can use a Tx beam partial sweep in a specific direction according to an environment or situation.

15 is a diagram illustrating an example of a discovery signal applicable to the present disclosure. The discovery signal 1501 may include a discovery message 1503 and a synchronization signal. The synchronization signal may include a sidelink-primary synchronization signal (S-PSS, 1505) and a sidelink-secondary sidelink signal (S-SSS, 1507) defined in an existing standard for a sidelink synchronization procedure. A sidelink-synchronization block (S-SSB) may include S-PSS and S-SSS. The sequence of the S-PSS and the S-SSS may be determined by a sidelink synchronization signal ID (SL-SSID). ID2 may determine the sequence of the S-PSS. ID1 and ID2 may determine the sequence of the S-SSS. The SL-SSID may have a value of 0 to 671. As an example, the SL-SSID may be expressed by Equation 1 below.

[Equation 1]

SL-SSID = 336*ID2 +ID1

ID1 = {0, 1, ... , 335}

ID2 = {0, 1}

If the synchronization signal uses S-PSS and S-SSS, there is an effect that the receiving terminal can reuse the S-PSS/S-SSS detector for sidelink synchronization. On the other hand, considering that the maximum number of transmission beams of the terminal is generally 64, the number of SL-SSIDs of 672 may be wasteful. Therefore, it may be efficient to use the SL-SSID in consideration of the number of transmission beams of the terminal. For example, 6 bits of the LSB of the SL-SSID may be used for the transmission beam ID, and the 4 bits of the MSB of the SL-SSID may be used for the purpose of beam management or discovery.

16 is a diagram illustrating an example of a discovery signal transmission method applicable to the present disclosure. In step S1601 , the transmitting terminal 1602 that wants to transmit data may transmit a discovery signal to the receiving terminal 1604 . The transmitting terminal 1602 that wants to transmit data may be referred to as an initiating UE. The initiating terminal 1602 may transmit a discovery signal by applying a transmit beam sweep for initial beam alignment with a receiving terminal before data transmission or service start. The sequence ID of the synchronization signal included in the discovery signal may be set as the transmission beam ID.

The discovery signal may include a synchronization signal and a discovery message. The synchronization signal included in the discovery signal may be used for fine time/frequency synchronization between the transmitting terminal and the receiving terminal. Coarse time/frequency synchronization between terminals may be performed based on a base station, GNSS, or a synchronization reference terminal (SyncRef UE) in a synchronization step, which is a step before the discovery step. The discovery message may include information necessary for a discovery procedure. As an example, the discovery message may include a UE ID and a service ID.

In step S1603 , the receiving terminal 1604 may transmit a discovery response signal to the initiating terminal 1602 . The receiving terminal 1604 may measure the signal strength or SNR of the discovery signal. The receiving terminal may determine a best Tx beam based on the measured signal strength or SNR. The reception terminal may know the transmission beam ID from the sequence ID of the synchronization signal included in the discovery signal. The reception terminal 1604 may transmit information on the best transmission beam to the initiating terminal 1602 through a discovery response signal. That is, the discovery response signal may include best transmission beam information.

17A and 17B are diagrams illustrating examples of discovery signal transmission applicable to the present disclosure. Referring to FIG. 17A , a discovery signal includes a Tx beam ID, and Tx beam sweeping is performed in all directions. That is, the UE may transmit the discovery signal including the Tx beam ID while performing a Tx beam full sweep. As an example, referring to FIG. 17A , the terminal may sequentially sweep all beams 0 to 7 by performing a full sweep of the transmission beam.

Referring to FIG. 17B , the UE may perform a Tx beam partial sweep in a specific direction. Specifically, by transmitting the discovery signal including the transmission beam ID, the terminal may perform partial sweep of the transmission beam in a specific direction. As an example, referring to FIG. 17B , the UE may perform partial sweeps of the transmission beam, and may only partially sweep numbers 2 to 6 . That is, the UE can flexibly operate the beam according to the environment or situation by transmitting the discovery signal including the transmission beam ID. In contrast, when the terminal does not transmit a transmit beam ID, only a form in which the number and order of transmit beams is fixed can be supported. For example, when the terminal does not transmit a transmit beam ID, the terminal may support only a full transmit beam sweep.

18 is a diagram illustrating an example of a transmitting terminal procedure applicable to the present disclosure. In step S1801, the UE may transmit at least one or more discovery signals having each beam direction. Here, the discovery signal may include a synchronization signal and a discovery message. As an example, the synchronization signal may be used for fine time and frequency synchronization between transmitting and receiving terminals after coarse time and frequency synchronization between terminals. A sequence ID of the synchronization signal may be set as a Tx beam ID. Specifically, the sequence ID of the synchronization signal may indicate the beam ID based on the beam direction of the discovery signal. Here, the sequence ID may determine the transmission sequence of the synchronization signal. In addition, the sequence ID of the synchronization signal may support the maximum number of transmission beams of the terminal. For example, when the maximum number of transmission beams is 64, the sequence ID may have a value of 0 to 63. As such, when the synchronization signal includes the transmit beam ID, the UE can perform the transmit beam ID determination only by detecting the synchronization signal without decoding the discovery message. Accordingly, power consumption of the terminal may be reduced. In addition, when the synchronization signal includes the Tx beam ID as described above, a flexible Tx beam shape can be used according to the environment or situation, compared to the case where the UE uses a predefined Tx beam sweep type. For example, when the discovery signal includes a transmit beam ID, the UE may perform a Tx beam partial sweep based on the beam ID.

The synchronization signal of the discovery signal may include an S-SSB. As an example, the synchronization signal may include S-PSS and S-SSS defined in existing standards. The sequence of the S-PSS and the sequence of the S-SSS may be determined based on a sidelink-synchronization signal ID (SL-SSID). For example, the SL-SSID may be determined by ID1 and ID2. Here, the SL-SSID may be expressed as in Equation 1 above. When the synchronization signal uses S-PSS and S-SSS, there is an effect that the receiving end can reuse the S-PSS and S-SSS detectors for sidelink synchronization.

In step S1803, the terminal may receive a discovery response signal from the terminal that has received at least one or more discovery signals. Here, the discovery response signal may include best beam ID information based on the beam ID.

19 is a diagram illustrating an example of a receiving terminal procedure applicable to the present disclosure. In step S1901, the terminal may receive at least one or more discovery signals having each beam direction. Here, the discovery signal may include a synchronization signal and a discovery message, as described above with reference to FIG. 18 .

In step S1903, the terminal may transmit a discovery response signal to the terminal that has transmitted at least one or more discovery signals. The terminal may measure the signal strength of the received discovery signal. Also, the UE may measure the SNR of the received discovery signal. The UE may determine a best Tx beam based on signal strength or SNR. Also, the terminal may find out the transmission beam ID from the sequence ID of the synchronization signal included in the received discovery signal. The UE may transmit the determined best transmission beam information to the UE that has transmitted the discovery signal.

20 is a diagram illustrating an example of beam sweeping applicable to the present disclosure. Referring to FIG. 20 , in mmWave sidelink communication, the UE may perform beam sweeping using beamforming. As an example, the terminal may perform beam sweeping to find the best beam with another terminal. As another example, the terminal may perform beam sweeping on the transmission beam. As another example, the terminal may perform beam sweeping on both the transmit beam and the receive beam. Terminal 1 2002 may perform beam sweeping on a transmit beam and/or a receive beam. Terminal 2 2004 may perform beam sweeping on a transmit beam and/or a receive beam. The terminal 3 2006 may perform beam sweeping on a transmit beam and/or a receive beam.

21 is a diagram illustrating an example of sidelink synchronization signal transmission applicable to the present disclosure. Specifically, FIG. 21 is a diagram illustrating a transmission scheme of S-SSB, which is a sidelink synchronization signal defined in 3GPP 4G NR specification. Since the current 3GPP specification does not define the mmWave sidelink, the S-SSB signal can be used only for time and frequency synchronization between terminals. The S-SSB transmission period of the sidelink may be defined as 160 ms. {1, 2, 4, 8, 16, 32, 64} S-SSBs may be repeated in the S-SSB transmission period. A position from the start position of the S-SSB transmission period to the first S-SSB may be defined as an S-SSB offset. The interval between S-SSBs repeated within the transmission period may be defined as an S-SSB interval. One S-SSB may have a length of 1 slot. The S-SSB offset and the S-SSB interval may be defined in units of slots. The transmission pattern of the S-SSB may be set at a necessary time or preset. As an example, the S-SSB transmission pattern may be configured at a required time by the base station. As another example, the transmission pattern of the S-SSB may be preconfigured in an internal storage device of the terminal in advance. The transmission pattern of the S-SSB may have the number of S-SSB repetitions, the S-SSB offset, and the S-SSB interval as elements.

22 is a diagram illustrating an example of a symbol structure applicable to the present disclosure. Referring to FIG. 22 , an upper cyclic prefix (CP) of FIG. 22 indicates a symbol structure within one slot of an S-SSB for a normal CP (CP) 2202 . The lower CP of FIG. 22 shows a symbol structure within one slot of the S-SSB for an extended CP (2204). The normal CP 2202 and the extended CP 2204 may include a symbol for AGC of the receiving end, a symbol for synchronization, and a physical sidelink broadcast channel (PSBCH) symbol, respectively. A symbol for synchronization may include S-PSS and S-SSS. The PSBCH symbol may include TDD SL configuration, in-coverage indicator, frame_number, slot_index information, and the like. The present disclosure proposes an S-SSB transmission method for initial beam alignment between terminals in mmWave sidelink communication. Specifically, the present disclosure proposes an S-SSB transmission method for avoiding inter-terminal beam interference when a UE transmits an S-SSB signal using transmission beam sweeping.

23 is a diagram illustrating an example of synchronization signal block transmission applicable to the present disclosure. Specifically, FIG. 23 is a diagram illustrating an example of using transmit beam sweeping when the UE repeatedly transmits the S-SSB in one S-SSB transmission period. Referring to FIG. 23 , 8 transmission beams may be mapped to 9 S-SSBs. A number of S-SSBs different from the number defined in the 3GPP specification may be mapped to the transmission beam. That is, the UE may transmit the number of S-SSBs different from the specification in one transmission period in consideration of the number of transmission beams. In addition, when the number of transmission beams is smaller than the number of S-SSB repetitions, the UE may repeat the transmission beams and map them to match the number of S-SSBs. For example, the terminal repeats the transmission beam as {Tx beam #1, Tx beam #1, Tx beam #2, Tx beam #2, can be mapped to match The receiving terminal may determine the best transmission beam by measuring the signal strength of the S-SSB during the S-SSB transmission period. The receiving terminal may report the best transmission beam information to the transmitting terminal. When the UE uses not only the transmit beam sweep but also the receive beam sweep, the measurement time may be (S-SSB transmission period * number of receive beams).

Unlike sub-6G sidelink communication that does not use beamforming, mmWave sidelink communication using beamforming may cause a problem when the receiving terminal determines the best beam. For example, if the S-SSB resources (time and frequency resources) of several transmitting terminals overlap, it may be difficult for the receiving terminal to determine the best transmission beam by measuring the S-SSB reception strength of a specific transmitting terminal. The 3GPP specification includes a configuration in which the frequency resource of the S-SSB signal is used equally for each terminal in order to reduce the overhead of the receiving terminal. The present disclosure proposes a method of differently setting an S-SSB transmission time point for initial beam alignment between terminals in mmWave sidelink communication for each transmitting terminal. By doing so, the receiving terminal can determine the best transmission beam for each transmitting terminal. Accordingly, the present disclosure proposes a method for a receiving terminal to determine a best transmission beam for each transmitting terminal.

24 is a diagram illustrating an example of an S-SSB transmission method applicable to the present disclosure. UEs may apply different S-SSB offsets, respectively. Referring to FIG. 24 , the S-SSB offset of UE 1 (UE 1, 2402), UE 2 (UE 2, 2404), and UE 3 (UE 3, 2406) may be set differently. Accordingly, collision between S-SSBs can be prevented.

25 is a diagram illustrating an example of an S-SSB transmission method applicable to the present disclosure. 25 shows an example of a procedure in which three terminals transmit S-SSB, and the number of terminals transmitting S-SSB is not limited to the number of the above-described embodiments.

A terminal participating in mmWave sidelink communication may pre-configure a configuration related to S-SSB transmission. Specifically, a group to which terminals participating in sidelink communication belong may preset a configuration related to S-SSB transmission. For example, a terminal group participating in mmWave sidelink communication may preset numerology and S-SSB transmission pattern. Here, the numerology may include a CP type, subcarrier spacing (SCS), and the like. The S-SSB transmission pattern may include an S-SSB offset, the number of S-SSB repetitions, and an S-SSB interval. The S-SSB offset may be given in the form of a resource pool. The terminals in the group may set both the number of S-SSB repetitions and the S-SSB interval to be the same. The UE may set the S-SSB transmission period to start at slot 0 of a frame where (Frame_number mod 16 ==0).

Hereinafter, a procedure for the UE to transmit the S-SSB for initial beam alignment will be described. Terminal 1 2502 may extract the S-SSB offset from the received S-SSB. Specifically, terminal 1 2502 may receive an S-SSB from a neighboring terminal before transmitting mmWave sidelink data. Terminal 1 2502 may decode a physical sidelink broadchannel (PSBCH) of the received S-SSB to find out a frame number (Frame_number) and a slot index (slot_index) of the received S-SSB. Terminal 1 2502 may obtain the offset of the S-SSB based on Equation 2 below.

[Equation 2]

S-SSB offset = { (LSB 4bits of Frame_number) x (number of slots in a frame) + (Slot_index) } mod (S-SSB interval)

Terminal 1 may remove the offset of the received S-SSB from the preset S-SSB offset pool. When there is no received S-SSB, UE 1 may start S-SSB transmission without removing the offset of the received S-SSB.

Terminal 1 may randomly select an offset from the S-SSB offset pool. UE 1 may perform Tx beam sweeping based on the selected S-SSB offset. UE 1 may transmit S-SSB based on transmission beam sweeping. As an example, UE 1 may transmit an S-SSB to UE 2 2504 based on transmission beam sweeping. UE 1 may transmit best transmission beam information to PSBCH when there is a reception S-SSB. The best Tx beam information may include an offset full index of the received S-SSB and an S-SSB index. The S-SSB index may be expressed by Equation 3 below.

[Equation 3]

S-SSB index = {(LSB 4bits of Frame_number) x (number of slots in a frame) + (Slot_index) - (S-SSB offset)} / (S-SSB interval)

Hereinafter, operation procedures of terminal 1 ( 2502 ), terminal 2 ( 2504 ), and terminal 3 ( 2506 ) will be described with reference to FIG. 25 . Terminal 1 may sense the S-SSB from a neighboring terminal before transmitting mmWave sidelink data. Terminal 1 may randomly select an offset from the S-SSB offset pool when there is no received S-SSB as a result of sensing. Terminal 1 may randomly select an offset and transmit S-SSB to UE 2 by applying transmit beam sweeping (S2501).

Terminal 2 2504 may receive the S-SSB from terminal 1 2502 . Terminal 2 may decode the received S-SSB to remove the offset of terminal 1 from the S-SSB offset pool. After removing the offset of UE 1, UE 2 may randomly select an offset from the S-SSB offset pool. Terminal 2 may perform transmission beam sweeping based on the randomly selected S-SSB offset. UE 2 may transmit S-SSB based on transmission beam sweeping. In this case, the terminal 2 may transmit the best transmission beam information to the terminal 1 . As an example, UE 2 may transmit best transmission beam information of the received S-SSB to UE 1 through PSBCH (S2503).

Terminal 3 2506 may receive the SSB from terminal 1 2502 and terminal 2 2504 . UE 3 may decode the received S-SSB of UE 1 and UE 2 to remove the offset of UE 1 and the offset of UE 2 from the S-SSB offset pool. UE 3 may randomly select an offset from the S-SSB offset pool after the offset is removed. Terminal 3 may perform transmit beam sweeping at the selected offset. Terminal 3 may transmit S-SSB based on transmit beam sweeping. In this case, the terminal 3 may transmit the best transmission beam information of the terminal that wants to communicate in the terminal 1 and the terminal 2 through the PSBCH. Terminal 3 may select a terminal to transmit the best transmission beam information based on the received S-SSB signal strength. As an example, UE 3 may transmit best transmission beam information to UE 1 having a greater signal strength of the received S-SSB.

Systems and various devices to which embodiments of the present disclosure are applicable

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

Hereinafter, an apparatus to which various embodiments of the present disclosure may be applied will be described. Although not limited thereto, various descriptions, functions, procedures, suggestions, methods, and/or operation flowcharts disclosed in this document may be applied to various fields requiring wireless communication/connection (eg, 5G) between devices.

Hereinafter, it will be exemplified in more detail with reference to the drawings. In the following drawings/descriptions, the same reference numerals may represent the same or corresponding hardware blocks, software blocks, or functional blocks, unless otherwise indicated.

26 shows an example of a communication system, according to an embodiment of the present disclosure. 24 may be combined with various embodiments of the present disclosure.

Referring to FIG. 26 , a communication system applied to the present disclosure includes a wireless device, a base station, and a network. Here, the wireless device refers to a device that performs communication using a wireless access technology (eg, 5G NR, LTE), and may be referred to as a communication/wireless/5G device. Although not limited thereto, the wireless device may include a robot 110a, a vehicle 110b-1, a vehicle 110b-2, an extended reality (XR) device 110c, a hand-held device 110d, and a home appliance. appliance) 110e, an Internet of Thing (IoT) device 110f, and an artificial intelligence (AI) device/server 110g. For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous driving vehicle, a vehicle capable of performing inter-vehicle communication, and the like. Here, the vehicles 110b-1 and 110b-2 may include an unmanned aerial vehicle (UAV) (eg, a drone). The XR device 110c includes augmented reality (AR)/virtual reality (VR)/mixed reality (MR) devices, and includes a head-mounted device (HMD), a head-up display (HUD) provided in a vehicle, a television, It may be implemented in the form of a smartphone, a computer, a wearable device, a home appliance, a digital signage, a vehicle, a robot, and the like. The portable device 110d may include a smartphone, a smart pad, a wearable device (eg, a smart watch, smart glasses), and a computer (eg, a laptop computer). The home appliance 110e may include a TV, a refrigerator, a washing machine, and the like. The IoT device 110f may include a sensor, a smart meter, and the like. For example, the base stations 120a to 120e and the network may be implemented as wireless devices, and a specific wireless device 120a may operate as a base station/network node to other wireless devices.

Here, the wireless communication technology implemented in the wireless devices 110a to 110f of the present specification may include a narrowband Internet of Things for low-power communication as well as LTE, NR, and 6G. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented in standards such as LTE Cat NB1 and/or LTE Cat NB2, and is limited to the above-mentioned names. no. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 110a to 110f of the present specification may perform communication based on the LTE-M technology. In this case, as an example, the LTE-M technology may be an example of an LPWAN technology, and may be called various names such as enhanced machine type communication (eMTC). For example, LTE-M technology is 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and/or 7) may be implemented in at least one of various standards such as LTE M, and is not limited to the above-described name. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 110a to 110f of the present specification is at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) in consideration of low power communication. It may include any one, and is not limited to the above-mentioned names. For example, the ZigBee technology can create PAN (personal area networks) related to small/low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

The wireless devices 110a to 110f may be connected to a network through the base stations 120a to 120e. AI technology may be applied to the wireless devices 110a to 110f, and the wireless devices 110a to 110f may be connected to the AI server 110g through a network. The network may be configured using a 3G network, a 4G (eg, LTE) network, or a 5G (eg, NR) network. The wireless devices 110a to 110f may communicate with each other through the base stations 120a to 120e/network, but may communicate directly (eg, sidelink communication) without using the base stations 120a to 120e/network. have. For example, the vehicles 110b-1 and 110b-2 may perform direct communication (eg, vehicle to vehicle (V2V)/vehicle to everything (V2X) communication). Also, the IoT device 110f (eg, a sensor) may directly communicate with another IoT device (eg, a sensor) or other wireless devices 110a to 110f.

Wireless communication/connection 150a, 150b, and 150c may be performed between the wireless devices 110a to 110f/base stations 120a to 120e, and the base stations 120a to 120e/base stations 120a to 120e. Here, wireless communication/connection includes uplink/downlink communication 150a and sidelink communication 150b (or D2D communication), and communication between base stations 150c (eg, relay, integrated access backhaul (IAB)). This can be done via radio access technology (eg 5G NR). Through the wireless communication/connection 150a, 150b, and 150c, the wireless device and the base station/wireless device, and the base station and the base station may transmit/receive wireless signals to each other. For example, the wireless communication/connection 150a , 150b , 150c may transmit/receive signals through various physical channels. To this end, based on various proposals of the present disclosure, various configuration information setting processes for transmission/reception of radio signals, various signal processing processes (eg, channel encoding/decoding, modulation/demodulation, resource mapping/demapping, etc.) , at least a part of a resource allocation process may be performed.

27 illustrates an example of a wireless device according to an embodiment of the present disclosure. The embodiment of FIG. 27 may be combined with various embodiments of the present disclosure.

Referring to FIG. 27 , a first wireless device 200a and a second wireless device 200b may transmit/receive wireless signals through various wireless access technologies (eg, LTE, NR). Here, {first wireless device 200a, second wireless device 200b} is {wireless device 110x, base station 120x} of FIG. 24 and/or {wireless device 110x, wireless device 110x) } can be matched.

The first wireless device 200a includes one or more processors 202a and one or more memories 204a, and may further include one or more transceivers 206a and/or one or more antennas 208a. The processor 202a controls the memory 204a and/or the transceiver 206a and may be configured to implement the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed herein. For example, the processor 202a may process information in the memory 204a to generate first information/signal, and then transmit a wireless signal including the first information/signal through the transceiver 206a. In addition, the processor 202a may receive the radio signal including the second information/signal through the transceiver 206a, and then store the information obtained from the signal processing of the second information/signal in the memory 204a. The memory 204a may be connected to the processor 202a and may store various information related to the operation of the processor 202a. For example, the memory 204a may provide instructions for performing some or all of the processes controlled by the processor 202a, or for performing the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed herein. may store software code including Here, the processor 202a and the memory 204a may be part of a communication modem/circuit/chip designed to implement a wireless communication technology (eg, LTE, NR). The transceiver 206a may be coupled with the processor 202a and may transmit and/or receive wireless signals via one or more antennas 208a. The transceiver 206a may include a transmitter and/or a receiver. The transceiver 206a may be used interchangeably with a radio frequency (RF) unit. In the present disclosure, a wireless device may refer to a communication modem/circuit/chip.

For example, the first wireless device may include a transceiver and a processor connected to the transceiver. The processor may control the transceiver to transmit at least one discovery signal having each beam direction. In addition, the processor may control to receive a discovery response signal from the terminal that has received the at least one or more discovery signals. The discovery signal may include a synchronization signal and a discovery message.

As another example, the first wireless device may include at least one memory and at least one processor functionally connected to the at least one memory. The at least one processor may control the first wireless device to transmit at least one discovery signal having each beam direction. The at least one processor may control to receive a discovery response signal from the terminal that has received the at least one or more discovery signals. The discovery signal may include a synchronization signal and a discovery message.

The second wireless device 200b performs wireless communication with the first wireless device 200a, and includes one or more processors 202b, one or more memories 204b, and additionally one or more transceivers 206b and/or one The above antenna 208b may be further included. The functions of the one or more processors 202b , one or more memories 204b , one or more transceivers 206b and/or one or more antennas 208b may include one or more processors 202a , one or more memories of the first wireless device 200a . 204a, one or more transceivers 206a and/or one or more antennas 208a.

For example, the second wireless device may include a transceiver and a processor connected to the transceiver. The processor may control the transceiver to receive at least one or more discovery signals having each beam direction. In addition, the processor may control to transmit a discovery response signal to the terminal that has transmitted the one or more discovery signals. The discovery signal may include a synchronization signal and a discovery message.

Hereinafter, hardware elements of the wireless devices 200a and 200b will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors 202a, 202b. For example, the one or more processors 202a, 202b may include one or more layers (eg, physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), and radio resource (RRC)). control) and a functional layer such as service data adaptation protocol (SDAP)). The one or more processors 202a, 202b may include one or more protocol data units (PDUs), one or more service data units (SDUs), messages, It can generate control information, data or information. The one or more processors 202a and 202b generate a signal (eg, a baseband signal) including a PDU, SDU, message, control information, data or information according to the functions, procedures, proposals and/or methods disclosed in this document. , may be provided to one or more transceivers 206a and 206b. The one or more processors 202a, 202b may receive signals (eg, baseband signals) from one or more transceivers 206a, 206b, and may be described, functions, procedures, proposals, methods, and/or flowcharts of operation disclosed herein. PDUs, SDUs, messages, control information, data, or information may be acquired according to the fields.

One or more processors 202a, 202b may be referred to as a controller, microcontroller, microprocessor, or microcomputer. One or more processors 202a, 202b 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 one or more processors 202a, 202b. The descriptions, functions, procedures, suggestions, methods, and/or flowcharts of operations disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, and the like. The descriptions, functions, procedures, proposals, methods, and/or flow charts disclosed in this document provide that firmware or software configured to perform is included in one or more processors 202a, 202b, or stored in one or more memories 204a, 204b. It may be driven by the above processors 202a and 202b. The descriptions, functions, procedures, proposals, methods, and/or flowcharts of operations disclosed herein may be implemented using firmware or software in the form of code, instructions, and/or a set of instructions.

As an example, a non-transitory first wireless device that stores at least one instruction may include the at least one instruction executable by the processor. The at least one command may instruct the first wireless device to transmit at least one or more discovery signals having respective beam directions. The at least one command may instruct the first wireless device to receive a discovery response signal from the terminal that has received the at least one or more discovery signals. The discovery signal may include a synchronization signal and a discovery message.

One or more memories 204a, 204b may be coupled to one or more processors 202a, 202b and may store various types of data, signals, messages, information, programs, codes, instructions, and/or instructions. One or more memories 204a, 204b may include read only memory (ROM), random access memory (RAM), erasable programmable read only memory (EPROM), flash memory, hard drives, registers, cache memory, computer readable storage media and/or It may be composed of a combination of these. One or more memories 204a, 204b may be located inside and/or external to one or more processors 202a, 202b. Additionally, one or more memories 204a, 204b may be coupled to one or more processors 202a, 202b through various technologies, such as wired or wireless connections.

The one or more transceivers 206a, 206b may transmit user data, control information, radio signals/channels, etc. referred to in the methods and/or operational flowcharts of this document to one or more other devices. The one or more transceivers 206a, 206b may receive user data, control information, radio signals/channels, etc. referred to in the descriptions, functions, procedures, suggestions, methods and/or flow charts, etc. disclosed herein, from one or more other devices. have. In addition, one or more transceivers 206a, 206b may be coupled to one or more antennas 208a, 208b via the one or more antennas 208a, 208b to the descriptions, functions, procedures, proposals, methods and/or disclosed herein. It may be set to transmit/receive user data, control information, radio signals/channels, etc. mentioned in an operation flowchart. In this document, one or more antennas may be a plurality of physical antennas or a plurality of logical antennas (eg, antenna ports). The one or more transceivers 206a, 206b converts the received radio signal/channel, etc. from the RF band signal to process the received user data, control information, radio signal/channel, etc. using the one or more processors 202a, 202b. It can be converted into a baseband signal. One or more transceivers 206a, 206b may convert user data, control information, radio signals/channels, etc. processed using one or more processors 202a, 202b from baseband signals to RF band signals. To this end, one or more transceivers 206a, 206b may include (analog) oscillators and/or filters.

28 illustrates an example of a vehicle or autonomous driving vehicle, according to an embodiment of the present disclosure. 28 illustrates a vehicle or an autonomous driving vehicle applied to the present disclosure. The vehicle or autonomous driving vehicle may be implemented as a mobile robot, a vehicle, a train, an aerial vehicle (AV), a ship, and the like, but is not limited to the shape of the vehicle. The embodiment of FIG. 28 may be combined with various embodiments of the present disclosure.

Referring to FIG. 28 , the vehicle or autonomous driving vehicle 600 includes an antenna unit 608 , a communication unit 610 , a control unit 620 , a driving unit 640a , a power supply unit 640b , a sensor unit 640c and autonomous driving. A portion 640d may be included. The antenna unit 650 may be configured as a part of the communication unit 610 .

The communication unit 610 may transmit/receive signals (eg, data, control signals, etc.) to and from external devices such as other vehicles, base stations (eg, base stations, roadside units, etc.), and servers. The controller 620 may perform various operations by controlling elements of the vehicle or the autonomous driving vehicle 100 . The controller 120 may include an Electronic Control Unit (ECU). The driving unit 640a may cause the vehicle or the autonomous driving vehicle 600 to run on the ground. The driving unit 640a may include an engine, a motor, a power train, a wheel, a brake, a steering device, and the like. The power supply unit 640b supplies power to the vehicle or the autonomous driving vehicle 600 , and may include a wired/wireless charging circuit, a battery, and the like. The sensor unit 640c may obtain vehicle status, surrounding environment information, user information, and the like. The sensor unit 640c includes an inertial measurement unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, an inclination sensor, a weight sensor, a heading sensor, a position module, and a vehicle forward movement. / may include a reverse sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illuminance sensor, a pedal position sensor, and the like. The autonomous driving unit 640d includes a technology for maintaining a driving lane, a technology for automatically adjusting speed such as adaptive cruise control, a technology for automatically driving along a predetermined route, and a technology for automatically setting a route when a destination is set. technology can be implemented.

For example, the communication unit 610 may receive map data, traffic information data, and the like from an external server. The autonomous driving unit 640d may generate an autonomous driving route and a driving plan based on the acquired data. The controller 620 may control the driving unit 640a to move the vehicle or the autonomous driving vehicle 600 along the autonomous driving path (eg, speed/direction adjustment) according to the driving plan. During autonomous driving, the communication unit 610 may obtain the latest traffic information data from an external server non/periodically, and may acquire surrounding traffic information data from surrounding vehicles. Also, during autonomous driving, the sensor unit 640c may acquire vehicle state and surrounding environment information. The autonomous driving unit 640d may update the autonomous driving route and the driving plan based on the newly acquired data/information. The communication unit 610 may transmit information about a vehicle location, an autonomous driving route, a driving plan, and the like to an external server. The external server may predict traffic information data in advance using AI technology or the like based on information collected from the vehicle or autonomous vehicles, and may provide the predicted traffic information data to the vehicle or autonomous vehicles.

Since examples of the above-described proposed method may also be included as one of the implementation methods of the present disclosure, it is clear that they may be regarded as a kind of proposed method. In addition, the above-described proposed methods may be implemented independently, or may be implemented in the form of a combination (or merge) of some of the proposed methods. A rule may be defined so that the information on whether the proposed methods are applied (or information on the rules of the proposed methods) is notified by the base station to the terminal through a predefined signal (eg, a physical layer signal or a higher layer signal). .

The present disclosure may be embodied in other specific forms without departing from the technical ideas and essential characteristics described in the present disclosure. Accordingly, the above detailed description should not be construed as restrictive in all respects but as exemplary. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present disclosure are included in the scope of the present disclosure. In addition, claims that are not explicitly cited in the claims may be combined to form an embodiment, or may be included as new claims by amendment after filing.

Embodiments of the present disclosure may be applied to various wireless access systems. As an example of various radio access systems, there is a 2nd Generation Partnership Project (3GPP) or a 3GPP2 system.

Embodiments of the present disclosure may be applied not only to the various radio access systems, but also to all technical fields to which the various radio access systems are applied. Furthermore, the proposed method can be applied to mmWave and THzWave communication systems using very high frequency bands.

Additionally, embodiments of the present disclosure may be applied to various applications such as free-running vehicles and drones.

Claims (16)

A method of operating a terminal in a wireless communication system, the method comprising: transmitting, by the terminal, at least one or more discovery signals having respective beam directions; and Receiving, by the terminal, a discovery response signal from the terminal that has received the at least one discovery signal; The discovery signal includes a synchronization signal and a discovery message. According to claim 1, A sequence ID of the synchronization signal indicates a beam ID based on a beam direction of the discovery signal. 3. The method of claim 2, partial sweep of the discovery signal based on the beam ID. 3. The method of claim 2, The discovery response signal includes best beam ID information based on the beam ID. According to claim 1, The synchronization signal includes a synchronization signal block (synchronization signal block), the synchronization signal block comprising a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), the method. 6. The method of claim 5, The sequence of the PSS and the SSS is determined based on a sidelink synchronization signal ID (sidelink synchronization signal ID, SL-SSID). In a terminal in a wireless communication system, transceiver; and a processor connected to the transceiver; The processor controls the transceiver to transmit at least one or more discovery signals having each beam direction, Control to receive a discovery response signal from the terminal that has received the at least one or more discovery signals, The discovery signal includes a synchronization signal (synchronization signal) and a discovery message (discovery message), the terminal. 8. The method of claim 7, A sequence ID of the synchronization signal indicates a beam ID based on a beam direction of the discovery signal. 9. The method of claim 8, The processor controls the transceiver to partially sweep the discovery signal based on the beam ID. 9. The method of claim 8, The discovery response signal includes best beam ID (best beam ID) information based on the beam ID, the terminal. 8. The method of claim 7, The synchronization signal includes a synchronization signal block (synchronization signal block), the synchronization signal block comprising a primary synchronization signal (primary synchronization signal, PSS) and a secondary synchronization signal (secondary synchronization signal, SSS), the terminal. 12. The method of claim 11, The sequence of the PSS and the SSS is determined based on a sidelink synchronization signal ID (SL-SSID), the terminal. A method of operating a terminal in a wireless communication system, the method comprising: receiving, by the terminal, at least one or more discovery signals having respective beam directions; and Transmitting, by the terminal, a discovery response signal to the terminal that has transmitted the at least one discovery signal; The discovery signal includes a synchronization signal and a discovery message. In a terminal in a wireless communication system, transceiver; and a processor connected to the transceiver; The processor controls the transceiver to receive at least one or more discovery signals having each beam direction, Control to transmit a discovery response signal to the terminal that has transmitted the at least one or more discovery signals, The discovery signal includes a synchronization signal (synchronization signal) and a discovery message (discovery message), the terminal. An apparatus comprising at least one memory and at least one processor operatively coupled to the at least one memory, the apparatus comprising: The at least one processor enables the device to Control to transmit at least one or more discovery signals having each beam direction, Control to receive a discovery response signal from the terminal that has received the at least one or more discovery signals, The discovery signal comprises a synchronization signal (synchronization signal) and a discovery message (discovery message), the apparatus. A non-transitory computer-readable medium storing at least one instruction, comprising: at least one instruction executable by a processor; The at least one command is Instructing the computer readable medium to transmit at least one or more discovery signals having respective beam directions, instructs the computer-readable medium to receive a discovery response signal from a terminal that has received the at least one or more discovery signals, The discovery signal comprises a synchronization signal (synchronization signal) and a discovery message (discovery message), the apparatus.

Images