WO2022211584A1

WO2022211584A1 - Drx operation method and device in wireless communication system

Info

Publication number: WO2022211584A1
Application number: PCT/KR2022/004731
Authority: WO
Inventors: 이원석; 박동현
Original assignee: 주식회사 아이티엘
Priority date: 2021-04-02
Filing date: 2022-04-01
Publication date: 2022-10-06
Also published as: KR20220137344A

Abstract

A method for a terminal supporting sidelink communication in a wireless communication system may be provided. The method for supporting sidelink communication may comprise the steps in which: a transmission terminal transmits SL DRX configuration information to a reception terminal; the transmission terminal receives assistance information from the reception terminal, wherein the reception terminal does not perform SL DRX configuration on the basis of the SL DRX configuration information, and the assistance information comprises Uu DRX configuration information of the reception terminal; the transmission terminal changes the SL DRX configuration in accordance with the Uu DRX configuration information on the basis of the assistance information, and transmits the changed SL DRX configuration information to the reception terminal; and the transmission terminal and the reception terminal perform SL DRX configuration on the basis of the changed SL DRX configuration information.

Description

DRX operation method and apparatus in a wireless communication system

The present disclosure relates to a method of operating discontinuous reception (DRX) in a wireless communication system. Specifically, it relates to a method and apparatus for performing a DRX operation in New Radio (NR) V2X (Vehicle to Everything).

The International Telecommunication Union (ITU) is developing an IMT (International Mobile Telecommunication) framework and standard, and recently, a discussion for 5G (5G) communication is underway through a program called "IMT for 2020 and beyond". .

In order to meet the requirements presented by "IMT for 2020 and beyond", the 3rd Generation Partnership Project (3GPP) New Radio (NR) system considers various scenarios, service requirements, potential system compatibility, etc., time-frequency It is being discussed in the direction of supporting various numerology for the resource unit criterion.

In addition, 5G communication is a high path-loss (path-loss) occurring on a high carrier frequency (carrier frequency), phase-noise (phase-noise), frequency offset (frequency offset) to overcome the poor channel environment such as multiple It is possible to support transmission of a physical signal or a physical channel through a beam of Through this, 5G communication can support applications such as eMBB (enhanced mobile broadband), mMTC (massive machine type communications), and URLLC (Ultra Reliable and Low Latency Communication).

In addition, V2X communication, which is a communication method for exchanging or sharing information such as traffic conditions, while communicating with road infrastructure and other vehicles while driving, may be considered. V2X stands for LTE (Long Term Evolution)/NR (New Radio)-based communication between vehicles, V2V (vehicle-to-vehicle), and V2P (Vehicle-to-vehicle) refers to LTE/NR-based communication between a vehicle and a terminal carried by an individual. vehicle-to-pedestrian) and V2I/N (vehicle-to-infrastructure/network), which means LTE/NR-based communication between a vehicle and a roadside unit/network. Here, the roadside unit (RSU) may be a transport infrastructure entity implemented by a base station or a fixed terminal. For example, it may be an entity that transmits a speed notification to a vehicle.

However, a collision between resources for V2X communication may occur in an environment in which a plurality of terminals coexist, thereby causing delay in V2X communication.

The technical problem of the present disclosure may provide a method and apparatus for operating SL DRX in a wireless communication system.

The technical problem of the present disclosure may provide a method and apparatus for setting an SL DRX configuration in consideration of Uu DRX of a receiving terminal.

The technical problem of the present disclosure may provide a method and apparatus for setting an SL DRX configuration based on SL DRX-related information received from a base station or preset SL DRX-related information.

The technical problem of the present disclosure may provide a method and apparatus for performing a logical channel prioritization (LCP) procedure in consideration of SL DRX.

The technical problem of the present disclosure may provide a method and apparatus for setting an SL DRX configuration in consideration of a packet delay budget (PDB).

The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those of ordinary skill in the art to which the present disclosure belongs from the description below. will be able

A method for a terminal to support sidelink communication in a wireless communication system according to an aspect of the present disclosure may be provided. In this case, the method for supporting sidelink communication includes the steps of, by a transmitting terminal, transmitting SL DRX configuration information to a receiving terminal, and receiving, by the transmitting terminal, auxiliary information from the receiving terminal. Without performing DRX configuration, the auxiliary information includes Uu DRX configuration information of the receiving terminal, the transmitting terminal changes the SL DRX configuration based on the Uu DRX configuration information based on the auxiliary information, and receives the changed SL DRX configuration information It may include transmitting to the terminal and performing SL DRX configuration by the transmitting terminal and the receiving terminal based on the changed SL DRX configuration information.

According to the present disclosure, it is possible to provide a method of operating SL DRX in a wireless communication system.

According to the present disclosure, there is an effect of reducing power consumption by setting the SL DRX configuration in consideration of the Uu DRX of the receiving terminal.

According to the present disclosure, there is an effect of setting the SL DRX configuration in consideration of quality of service (QoS) and traffic patterns by configuring the SL DRX based on the SL DRX related information received from the base station or the preset SL DRX related information.

The technical problem of the present disclosure has the effect of allowing the transmitting terminal to receive SL data in the on-duration of the receiving terminal by performing the LCP procedure in consideration of SL DRX.

The technical problem of the present disclosure has the effect of allowing the transmitting terminal to receive SL data in the on-duration of the receiving terminal by setting the SL DRX configuration in consideration of the PDB.

Effects obtainable in the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those of ordinary skill in the art to which the present disclosure belongs from the description below. will be.

1 is a diagram for explaining an NR frame structure to which the present disclosure can be applied.

2 is a diagram illustrating an NR resource structure to which the present disclosure can be applied.

3 is a diagram illustrating an NR sidelink slot structure to which the present disclosure can be applied.

4 is a diagram illustrating an NR sidelink frequency to which the present disclosure can be applied.

5 is a diagram illustrating a method of measuring a Channel Busy Ratio (CBR) to which the present disclosure can be applied.

6 is a diagram illustrating a DRX operation to which the present disclosure can be applied.

7 is a diagram illustrating a DRX operation to which the present disclosure can be applied.

8 is a diagram for explaining the structure of a synchronization signal block to which the present disclosure can be applied.

9 is a diagram for explaining the configuration of a MAC PDU to which the present disclosure can be applied.

10 is a diagram illustrating an example of a method for determining a sidelink transmission slot based on terminal sensing to which the present disclosure can be applied.

11 is a diagram for explaining a V2X resource allocation scheme to which the present disclosure can be applied.

12 is a diagram illustrating a sidelink buffer status report (SL BSR) MAC control element to which the present disclosure can be applied.

13 may be a sidelink operation scenario to which the present disclosure may be applied.

14 is a diagram illustrating a method in which on-durations of Uu DRX and SL DRX to which the present disclosure can be applied are aligned.

15 is a diagram illustrating a method of configuring SL DRX based on assistance information to which the present disclosure can be applied.

16 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied sets SL DRX in consideration of a Uu DRX configuration of a receiving terminal.

17 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied sets an SL DRX cycle in consideration of Uu DRX of a receiving terminal.

18 is a diagram illustrating a method in which SL DRX and Uu DRX of a receiving terminal to which the present disclosure can be applied are configured in the same subframe.

19 is a diagram illustrating a method in which SL DRX and Uu DRX of a receiving terminal to which the present disclosure can be applied are configured in the same subframe.

20 is a diagram illustrating a method of setting an SL DRX configuration to which the present disclosure can be applied.

21 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied configures SL DRX of a receiving terminal.

22 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied configures SL DRX of a receiving terminal.

23 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied configures SL DRX of a receiving terminal.

24 is a diagram illustrating a method of setting a time gap to which the present disclosure can be applied.

25 is a diagram illustrating a method of configuring SL DRX in a mode 2 terminal to which the present disclosure can be applied.

26 is a diagram illustrating a method of determining an SL DRX cycle to which the present disclosure can be applied.

27 is a diagram illustrating an SL DRX configuration method to which the present disclosure can be applied.

28 is a diagram illustrating an SL DRX configuration method to which the present disclosure can be applied.

29 is a diagram illustrating an SL DRX configuration method to which the present disclosure can be applied.

30 is a flowchart illustrating an SL DRX configuration setting method to which the present disclosure can be applied.

31 is a diagram illustrating a base station apparatus and a terminal apparatus to which the present disclosure can be applied.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art to which the present disclosure pertains can easily implement them. However, the present disclosure may be embodied in several different forms and is not limited to the embodiments described herein.

In describing the embodiments of the present disclosure, if it is determined that a detailed description of a well-known configuration or function may obscure the gist of the present disclosure, a detailed description thereof will be omitted. And, in the drawings, parts not related to the description of the present disclosure are omitted, and similar reference numerals are attached to similar parts.

In the present disclosure, when a component is "connected", "coupled" or "connected" to another component, it is not only a direct connection relationship, but also an indirect connection relationship in which another component exists in the middle. may also include. Also, when it is said that a component includes "includes" or "has" another component, it means that another component may be further included without excluding other components unless otherwise stated. .

In the present disclosure, terms such as first, second, etc. are used only for the purpose of distinguishing one component from other components, and unless otherwise specified, do not limit the order or importance between the components. Accordingly, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment is referred to as a first component in another embodiment. can also be called

In the present disclosure, components that are distinguished from each other are for clearly explaining each characteristic, and do not necessarily mean that the components are separated. That is, a plurality of components may be integrated to form one hardware or software unit, or one component may be distributed to form a plurality of hardware or software units. Accordingly, even if not specifically mentioned, such integrated or dispersed embodiments are also included in the scope of the present disclosure.

In the present disclosure, components described in various embodiments do not necessarily mean essential components, and some may be optional components. Accordingly, an embodiment composed of a subset of components described in one embodiment is also included in the scope of the present disclosure. In addition, embodiments including other components in addition to components described in various embodiments are also included in the scope of the present disclosure.

The present disclosure describes a wireless communication network as a target, and an operation performed in the wireless communication network is performed in the process of controlling the network and transmitting or receiving a signal in a system (eg, a base station) having jurisdiction over the wireless communication network, or This can be done in the process of transmitting or receiving a signal from a terminal coupled to a wireless network.

It is obvious that various operations performed for communication with a terminal in a network including a plurality of network nodes including a base station may be performed by the base station or other network nodes other than the base station. 'Base station (BS: Base Station)' may be replaced by terms such as fixed station, Node B, eNodeB (eNB), ng-eNB, gNodeB (gNB), and access point (AP). . In addition, 'terminal' may be replaced by terms such as User Equipment (UE), Mobile Station (MS), Mobile Subscriber Station (MSS), Subscriber Station (SS), and non-AP station. can

In the present disclosure, transmitting or receiving a channel includes the meaning of transmitting or receiving information or a signal through a corresponding channel. For example, transmitting the control channel means transmitting control information or a signal through the control channel. Similarly, to transmit a data channel means to transmit data information or a signal over the data channel.

In the following description, the term NR (New Radio) system is used for the purpose of distinguishing a system to which various examples of the present disclosure are applied from an existing system, but the scope of the present disclosure is not limited by these terms .

The NR system supports various subcarrier spacing (SCS) considering various scenarios, service requirements, and potential system compatibility. In addition, the NR system has a plurality of channels in order to overcome a poor channel environment such as high path-loss, phase-noise, and frequency offset occurring on a high carrier frequency. It is possible to support transmission of a physical signal/channel through a beam of Through this, the NR system can support applications such as enhanced mobile broadband (eMBB), massive machine type communications (mmTC)/ultra machine type communications (uMTC), and ultra-reliable and low latency communications (URLLC).

Hereinafter, 5G mobile communication technology may be defined including not only the NR system, but also the existing Long Term Evolution-Advanced (LTE-A) system and Long Term Evolution (LTE) system. 5G mobile communication may include a technology that operates in consideration of backward compatibility with a previous system as well as a newly defined NR system. Accordingly, the following 5G mobile communication may include a technology operating based on an NR system and a technology operating based on a previous system (e.g., LTE-A, LTE), and is not limited to a specific system.

First, the physical resource structure of the NR system to which the present invention is applied will be briefly described.

The basic unit of time domain in NR is

can be,

, and may be N=4096. On the other hand, in LTE, the basic unit of time domain is

can be,

ego,

=2048. The constant for the multiple relationship between the NR time base unit and the LTE time base unit is k=

can be defined as

Referring to FIG. 1 , the time structure of a frame for downlink/uplink (DL/UL) transmission is

can have Here, one frame is

It consists of 10 subframes corresponding to time. The number of consecutive OFDM symbols per subframe is

=

can be In addition, each frame may be divided into two half frames of the same size, half frame 1 may be composed of subframes 0-4, and half frame 2 may be composed of subframes 5-9.

denotes a timing advance (TA) between the downlink (DL) and the uplink (UL). Here, the transmission timing of the uplink transmission frame i is determined based on the downlink reception timing in the terminal based on Equation 1 below.

[Equation 1]

here,

may be a TA offset value generated due to a duplex mode difference or the like. In Frequency Division Duplex (FDD)

has a value of 0, but in TDD (Time Division Duplex), considering the margin for DL-UL switching time,

can be defined as a fixed value of . For example, in TDD (Time Division Duplex) of FR1 (Frequency Range 1), which is a frequency of sub 6 GHz or less

is 39936

or 25600

can be 39936

is 20.327 μs, and 25600

is 13.030 μs. In addition, in FR2 (Frequency Range 2), which is a millimeter wave (mmWave) frequency,

is 13792

can be At this time, 13792

is 7.020 μs.

A resource element (RE) in a resource grid may be indexed according to each subcarrier spacing. Here, one resource grid may be generated per antenna port and per subcarrier spacing. Uplink and downlink transmission and reception may be performed based on a corresponding resource grid.

In the frequency domain, one resource block (RB) consists of 12 REs, and an index (nPRB) for one RB may be configured for every 12 REs. The index for the RB may be utilized within a specific frequency band or system bandwidth. The index for the RB may be defined as in Equation 2 below. here,

denotes the number of subcarriers per one RB, and k denotes a subcarrier index.

[Equation 2]

Various pneumatics can be set to satisfy various services and requirements of the NR system. For example, one subcarrier spacing (SCS) may be supported in the LTE/LTE-A system, but a plurality of SCSs may be supported in the NR system.

New Numerology for NR systems supporting multiple SCSs, to solve the problem of not being able to use a wide bandwidth in a frequency range or carrier such as 700 MHz or 2 GHz, 3 GHz or less, 3 GHz-6 GHz , can operate in a frequency range or carrier such as 6GHz-52.6GHz or 52.6GHz or higher.

Table 1 below shows examples of pneumatology supported by the NR system.

[Table 1]

Referring to Table 1, the numerology may be defined based on subcarrier spacing (SCS), cyclic prefix (CP) length, and the number of OFDM symbols per slot used in an orthogonal frequency division multiplexing (OFDM) system. The above values may be provided to the UE through higher layer parameters DL-BWP-mu and DL-BWP-cp for downlink and higher layer parameters UL-BWP-mu and UL-BWP-cp for uplink. .

In Table 1, when the subcarrier spacing configuration index u is 2, the subcarrier spacing Δf is 60 kHz, and a normal CP and an extended CP may be applied. In the case of other numerical indexes, only normal CP may be applied.

A normal slot may be defined as a basic time unit used to basically transmit one piece of data and control information in the NR system. The length of the normal slot may be basically set to the number of 14 OFDM symbols. In addition, unlike the slot, the subframe has an absolute time length corresponding to 1 ms in the NR system, and can be used as a reference time for the length of another time interval. Here, for coexistence or backward compatibility between the LTE system and the NR system, a time interval such as a subframe of LTE may be required for the NR standard.

For example, in LTE, data may be transmitted based on a Transmission Time Interval (TTI), which is a unit time, and the TTI may be set in units of one or more subframes. Here, one subframe may be set to 1 ms, and 14 OFDM symbols (or 12 OFDM symbols) may be included.

In addition, a non-slot may be defined in the NR. The non-slot may mean a slot having a number smaller than a normal slot by at least one symbol. For example, when a low delay time is provided as in the URLLC service, the delay time may be reduced through a non-slot having a smaller number of symbols than a normal slot. Here, the number of OFDM symbols included in the non-slot may be determined in consideration of the frequency range. For example, in a frequency range of 6 GHz or higher, a non-slot of 1 OFDM symbol length may be considered. As a further example, the number of OFDM symbols defining a non-slot may include at least two OFDM symbols. Here, the range of the number of OFDM symbols included in the non-slot may be set as the length of the mini-slot up to a predetermined length (eg, normal slot length-1). However, as a non-slot standard, the number of OFDM symbols may be limited to 2, 4, or 7 symbols, but is not limited thereto.

Also, for example, in the unlicensed band of 6 GHz or less, subcarrier spacing corresponding to

u

1 and 2 is used, and in the unlicensed band above 6 GHz, subcarrier spacing corresponding to

u

3 and 4 may be used. For example, when u is 4, it may be used for a Synchronization Signal Block (SSB).

[Table 2]

Table 2 shows the number of OFDM symbols per slot in the case of a normal CP for each subcarrier spacing configuration (u) (

), number of slots per frame (

), the number of slots per subframe (

) is indicated. Table 2 shows the above-described values based on a normal slot having 14 OFDM symbols.

[Table 3]

Table 3 shows the number of slots per frame and slots per subframe based on a normal slot in which the number of OFDM symbols per slot is 12 when extended CP is applied (that is, when u is 2 and subcarrier spacing is 60 kHz) represents the number of

As described above, one subframe may correspond to 1 ms on the time axis. Also, one slot may correspond to 14 symbols on the time axis. For example, one slot may correspond to 7 symbols on the time axis. Accordingly, the number of slots and symbols that can be considered each within 10 ms corresponding to one radio frame may be set differently. Table 4 may indicate the number of slots and the number of symbols according to each SCS. In Table 4, SCS of 480 kHz may not be considered, but is not limited to these examples.

[Table 4]

V2X service (e.g. LTE Rel-14 V2X) may support basic requirements for V2X services. The requirements are basically designed in consideration of road safety service. Here, V2X terminals (User Equipment, UE) may exchange state information through a sidelink (Sidelink). In addition, the V2X UE may exchange information with infrastructure nodes and/or pedestrians.

V2X service (e.g. LTE Rel-15) is carrier aggregation in the sidelink, high order modulation (high order modulation), delay reduction (latency reduction), transmission diversity (Tx diversity) and sTTI (Transmission Time) Interval) may support at least any one or more. For this, a new feature may be applied to V2X communication. Specifically, V2X UE may operate in consideration of coexistence with other V2X UEs. As an example, V2X UE may use the same resource pool as other V2X UEs.

As an example, in consideration of use cases for V2X service support as SA (System Aspect) 1, technical features may be classified based on four categories as shown in Table 5 below, but the present invention is not limited thereto. In Table 5, Vehicles Platooning may be a technique in which a plurality of vehicles dynamically form a group and operate similarly. Extended Sensors may be a technology for collecting and exchanging data acquired from a sensor or a video image. Advanced Driving may be a technology in which a vehicle is driven based on full automation or semi-automation. Remote driving may be a technology that provides a technology and an application for remote control of a vehicle, and more detailed information on the above-described bar may be shown in Table 5 below.

[Table 5]

[Table 11]

Next, the sidelink HARQ procedure is described. Whether the V2X terminal reports the HARQ feedback is indicated by higher layer (e.g. RRC) configuration and SCI signaling (e.g. 2nd SCI). As an example, when the V2X terminal performs communication based on groupcast, the HARQ feedback report may be determined based on the distance between the transmitting terminal and the receiving terminal.

When the V2X terminal performs at least one of unicast and groupcast, sidelink HARQ feedback may be enabled or disabled. Here, the enabling/disabling of HARQ feedback may be determined based on at least one of a channel condition (e.g. RSRP), a transmitting terminal/receiving terminal distance, and a QoS requirement.

In the case of groupcast, whether or not to transmit HARQ feedback may be determined by the physical distance between the transmitting terminal and the receiving terminal. Here, when HARQ feedback is performed based on groupcast, the receiving terminal may operate by feeding back a negative response only when PSSCH decoding fails. This may be an option 1 operation. On the other hand, when HARQ feedback is performed based on groupcast, the receiving terminal may operate by feeding back an affirmative response or negative response based on whether PSSCH decoding is successful, which may be an option 2 operation. In the option 1 operation of feeding back only a negative response to the HARQ NACK based on the groupcast, if the physical distance between the transmitting terminal and the receiving terminal is less than or equal to the communication range requirement, the feedback on the PSSCH may be performed. On the other hand, when the physical distance between the transmitting terminal and the receiving terminal is greater than the communication range requirement, the V2X terminal may not perform feedback on the PSSCH.

In this case, the location of the transmitting terminal is indicated to the receiving terminal through the SCI associated with the PSSCH. The receiving terminal estimates the distance to the transmitting terminal based on the information included in the SCI and its own location information, and may operate as described above.

In addition, when unicast communication is performed based on V2X, a case in which sidelink HARQ feedback is enabled may be considered. The receiving terminal may generate and transmit the HARQ ACK/NACK for the PSSCH based on whether the decoding of the corresponding transport block (TB) is successful.

Next, in the NR sidelink resource allocation mode, there is a mode in which the base station schedules sidelink transmission resources. Here, the mode in which the base station schedules the sidelink transmission resource may be mode 1. For example, when the V2X terminal is located within the base station coverage, the V2X terminal may receive sidelink resource information from the base station based on mode 1. On the other hand, there is a mode in which the V2X terminal directly determines a resource for sidelink transmission among sidelink resources configured by the base station/network or pre-configured sidelink resources. Here, the mode in which the terminal directly determines the sidelink transmission resource may be mode 2.

In addition, the sidelink received signal strength indicator (SL RSSI) is an average value (in [W]) of the total received power measured in subchannels configured in OFDM symbols of a slot configured for PSCCH and PSSCH. Defined.

In addition, the V2X terminal may measure the SL CBR (Sidelink Channel Busy Ratio) in slot n. Here, the CBR measurement is performed within a CBR measurement window ([n-a, n-1]). The CBR measurement window is set based on the “timeWindowSize-CBR” upper layer parameter value, and the a value has one of 100 or 100·2 μ slots. The CBR measurement is a value defining a ratio of subchannels having an SL-RSSI value exceeding a certain threshold among subchannels in the entire resource pool.

As an example, FIG. 5 is a diagram illustrating a method of measuring an SL CR (Channel Occupancy Ratio) to which the present disclosure can be applied.

Referring to FIG. 5 , the V2X terminal may measure the CR in slot n. Here, up to the slot [n-a, n+b] is a slot allowed for the V2X terminal, and the slot [n-a, n-1] is a slot used by the V2X terminal for SL transmission. The CR value in slot n is the sum of the total number of subchannels used for SL transmission in slot [n-a, n-1] and the total number of subchannels allocated to the UE for SL transmission in [n, n+b] may be a value divided by the number of all subchannels configured in the transmission resource pool corresponding to [n-a, n+b] time.

Specifically, in the time interval (slots [n-a, n-1]) used for sidelink transmission, the value a always has a positive value. On the other hand, the value of b within the time (slots [n, n+b]) for counting the number of subchannels of the resource allowed for the UE has a value of 0 or a positive number. The values of a and b are determined to satisfy both a+b+1 = 1000 or 1000·2μ slots condition and b < (a+b+1)/2 condition by the terminal implementation. The a+b+1 = 1000 or 1000·2 μ slots condition is set to use one of 1000 or 1000·2 μ slots by the “timeWindowSize-CR” upper layer parameter. Also, the value of n+b must not exceed the last transmission opportunity of the grant for the current transmission. Here, the slots for CBR and CR may be physical slots, and CBR and CR may be measured whenever transmission is performed.

Also, as an example, a discontinuous reception (DRX) operation of the terminal may be considered. The DRX operation is an operation in which the terminal performs reception discontinuously in a predetermined period, and thus power consumption can be reduced. The UE may monitor a paging message in a paging occasion based on a paging DRX cycle in a Radio Resource Control (RRC) idle state. In addition, the UE may reduce power consumption by performing physical downlink control channel (PDCCH) monitoring in on duration based on the DRX operation in the RRC connection state.

More specifically, referring to FIG. 6 , the UE may monitor the PDCCH in the RRC connection state and receive a DL grant and DL data (S610). Here, the UE receives the DL grant and DL data. Upon reception, a DRX inactivity timer and a basic RRC inactivity timer may be (re)started. That is, the DRX inactivity timer may be started so that the UE does not enter the DRX state to secure a certain period at the time when the DL data is received. In addition, the RRC inactivity timer may be started so that the UE does not enter the RRC idle state to secure a certain period at the time when the DL data is received.

When a UL grant is generated in the UE, the DRX deactivation timer and the RRC deactivation timer may be (re)started, and the UE may transmit UL data. (S620) The UE receives the UL grant and transmits UL data The DRX inactivity timer may be started so as not to be converted to the DRX state to secure a certain period at the time of the operation. In addition, the RRC inactivity timer may be started so that the UE does not enter the RRC idle state to secure a predetermined period at the time of receiving the UL grant and transmitting UL data.

That is, when a grant for data reception and transmission occurs, the UE may (re)start the DRX deactivation timer and the RRC deactivation timer. Here, when the DRX deactivation timer is driven, the UE may continuously perform PDCCH monitoring. After the DRX deactivation timer and RRC deactivation timer are started, if a DL grant or UL grant does not occur in the UE until the timer expires, if a short DRX cycle is configured in the UE, a short DRX cycle may start. have. (S630) Also, as an example, when the terminal receives a DRX command and a short DRX cycle is configured in the terminal, a short DRX cycle may start in the terminal. Here, the DRX command may be received as a DRX command MAC CE, and the DRX command MAC CE may be identified through the LCID of the MAC PDU subheader. For example, the short DRX cycle may be set in consideration of Voice over Internet Protocol (VOIP), but may not be limited thereto.

That is, when the terminal receives the DRX Command MAC CE, the on-duration timer and the DRX deactivation timer are stopped, and if a short DRX cycle is set, a short DRX cycle timer is executed based on the set short DRX cycle. can drive On the other hand, if the short DRX cycle is not configured, a long DRX cycle based on the long DRX cycle timer is driven. Here, the short DRX cycle timer may be started (or restarted) from the first symbol after receiving the DRX MAC Command MAC CE or from the first symbol after the DRX deactivation timer expires. When the short DRX cycle starts, the UE does not monitor the PDCCH during the DRX sleep period and may perform PDCCH monitoring only in the on-duration period, thereby reducing power consumption. Here, when the UE confirms the DL grant or the UL grant through PDCCH monitoring, the DRX inactivity timer and the RRX inactivity timer may be restarted. On the other hand, if the DL grant or UL grant does not occur until the short DRX cycle timer expires, the UE may end the short DRX cycle and start the long DRX cycle. (S640) Also, as an example, when the terminal receives the Long DRX Command MAC CE, the short DRX cycle timer is stopped and the long DRX cycle can be started. As another example, when the terminal receives the Long DRX Command MAC CE, the on-duration timer and the DRX deactivation timer may be stopped, and a long DRX cycle may be started.

Also, as an example, the short DRX cycle and the long DRX cycle have respective cycles and may have a DRX start offset (drxStartOffset) value. Here, the on-duration start subframe may be determined based on the DRX start offset from the period start point. The DRX on-duration timer (drx-onDurationTimer) may be started based on the start time of the on-duration.

The UE may not monitor the PDCCH in the DRX sleep interval within the long DRX cycle, but may perform PDCCH monitoring in the on-duration interval. Here, when the UE does not receive a DL grant or a UL grant for a time corresponding to the timer value after the RRC inactivity timer is started, the RRC inactivity timer may expire. When the RRC deactivation timer expires, the UE may be switched to the RRC idle state (S650). In this case, the UE may operate in the RRC idle state based on a paging DRX cycle.

Also, as an example, referring to FIG. 7 , the UE may perform a DRX operation in consideration of hybrid automatic repeat request (HARQ) feedback. Specifically, the RRC connection state UE may receive a DL grant and DL data by performing PDCCH monitoring (S710). Here, the UE may (re)start the DRX deactivation timer and the RRC deactivation timer. In this case, after receiving the DL data, the UE may transmit ACK/NACK information indicating whether the reception of the DL data is successful to the base station. As an example, the UE may successfully receive the DL data and complete the data reception by transmitting an ACK to the base station.

In addition, the UE may receive the UL grant and transmit UL data to the base station, and may (re)start the DRX deactivation timer and the RRC deactivation timer (S720). After that, the base station indicates whether the UL data transmission is successful. ACK/NACK information may be transmitted to the terminal. For example, the base station may successfully receive the UL data, and may transmit an ACK to the terminal to complete data transmission.

A case in which the UE receives the DL grant but fails to receive data due to failure in decoding DL data may be considered. At this time, the terminal transmits the NACK to the base station, and data retransmission may be performed based on this. (S730) Here, the HARQ RTT (Round Trip Time) timer (HARQ RTT Timer) completes the DL HARQ feedback (NACK) transmission. After that, it can start from the first symbol. The HARQ RTT timer may be a timer for a period after NACK transmission until DL HARQ retransmission is performed. The UE does not monitor the PDCCH indicating retransmission for the corresponding HARQ process while the HARQ RTT timer is operating, and when the HARQ RTT timer expires, the UE may perform PDCCH monitoring in anticipation of retransmission. In addition, the DRX retransmission timer may be started from the first symbol immediately after the HARQ RTT timer expires. (S740) The UE may perform PDCCH monitoring while the DRX retransmission timer is running, and transmit retransmission data. A scheduling DL grant may be received. If the UE succeeds in decoding the DL data based on the DL grant, it may transmit an ACK to the base station (S750). Here, the DL grant for retransmission data may not restart the above-described DRX deactivation timer, and DRX deactivation The timer may expire before the DRX retransmission timer expires. However, since the DRX retransmission timer is running, the UE does not enter the short DRX cycle, and may enter the short DRX cycle after the DRX retransmission timer expires (S760).

In addition, as an example, when the terminal performs UL data transmission (ie, when MAC PDU is transmitted), drx-HARQ-RTT-TimerUL is the first symbol after the end of the first repetition of the corresponding PUSCH. It begins. After the corresponding timer expires, the UE may expect to receive a UL grant for PUSCH retransmission, and may perform retransmission based on the received UL grant.

Also, as an example, the DRX cycle may be synchronized between the terminal and the base station (e.g. gNB). That is, the base station may recognize the DRX sleep state or the DRX awake state of the terminal, and may schedule the terminal accordingly.

In addition, the UE cannot perform PDCCH monitoring in the DRX sleep state, as described above. Since the base station recognizes the DRX cycle of the terminal, it may delay PDCCH transmission until the nearest wake-up cycle. In addition, in the case of UL transmission, the UE may transmit a Scheduling Request (SR) in the UL. For example, even when the terminal is in the DRX idle state, when UL data is generated in the terminal, the SR may be transmitted to the base station to receive the UL grant.

In addition, as an example, in addition to the timer and parameters described above, the MAC (e.g. gNB MAC) of the base station may control the DRX of the terminal by transmitting a MAC CE DRX command (e.g. DRX Command MAC CE or Long DRX Command MAC CE). This is as described above. In addition, when DRX is configured in the UE, the same operation as in the case of receiving/transmitting MAC PDUs for each configured DL/UL grant and PDCCH reception at active time may be applied.

Also, as an example, the base station (e.g. gNB) may control the on-duration time interval through RRC configurations of DRX or instruct to follow a long DRX cycle. The base station can recognize that DL transmission does not exist in the corresponding terminal through the above description, and can prevent the terminal from being activated in order to reduce power consumption of the terminal. Also, as an example, when DRX is set in the terminal, the activation time may include a time during which at least one of “drx-onDurationTimer”, “drx-InactivityTimer”, “drx-RetransmissionTimerDL” and “drx-RetransmissionTimerUL” is driven. have. In addition, the activation time may include a time during which “ra-ContentionResolutionTimer” is operated. In addition, the activation time may include a time during which the SR is transmitted on a Physical Uplink Control Channel (PUCCH) and is pending. In addition, the activation time is an RA preamble in which the PDCCH for new transmission indicated according to the C-RNTI (Radio Network Temporary Identifier) is not selected by the MAC entity from among the Contention Based Random Access (CBRA) preambles. After successful reception of RAR for (RA preamble), it may include a time that is not received.

As described above, the DRX operation may be performed, and parameters related to the DRX operation controlled by the RRC may be as shown in Table 12 below.

[Table 12]

In addition, as an example, in a new communication system (e.g. NR), a DRX operation for handling a plurality of SCSs may be considered in consideration of the above-described numerology. For example, when configuring the DRX cycle, a long DRX cycle may be configured for a general service or traffic (e.g. bursty traffic). In addition, a short DRX cycle may include periodic transmission of a short cycle such as Voice of Internet Protocol (VoIP). It may be selectively configured in consideration of the traffic service. In addition, when the latest data is scheduled in addition to the long DRX operation, the short DRX cycle is first applied for a predetermined period (e.g. 20ms for VoIP packet (having per 20ms traffic pattern)), and then the long DRX cycle may be used, but the above-described It is not limited to an Example.

Also, as an example, the unit of the DRX timer may be configured in units of ms in consideration of a case in which a plurality of numerologies exist in a new communication system (e.g. NR). However, this is only one example, and it may be possible for the DRX timer to be set based on other units, and is not limited to the above-described embodiment.

In addition, as an example, when performing a HARQ retransmission operation in asynchronous HARQ (asynchronous HARQ), which is a method of allocating resources at an arbitrary time for retransmission, the base station may perform retransmission of an error TB (Transport Block) quickly. A timer may be set to activate the terminal in order to schedule retransmission. As an example, the timer may correspond to the HARQ RTT timer. Also, as an example, the timer may be started when an error is confirmed in the TB, and is not limited to the above-described embodiment.

The following describes a new NR sidelink that satisfies the requirements for newly advanced NR sidelink services. However, as an example, the following may be applied not only to the more advanced NR V2X service, but also to other NR sidelink-based services (e.g. public safety, commercial use case (e.g. wearable)). Hereinafter, for the convenience of description, the more advanced NR V2X service will be described based on, but not limited thereto. Here, the NR sidelink frequency for NR sidelink operation is FR1 (410 MHz to 7.125 GHz), FR2 (24.25 GHz to 52.6 GHz) and 52.6 GHz. can In addition, the NR sidelink frequency for NR sidelink operation considers all frequency bands in which unlicensed ITS bands and licensed ITS bands and NR systems are operated that may exist in a lower frequency band than FR2. and is not limited to a specific band.

Also, as an example, the following may be commonly applied to all of the possible frequency bands. The NR sidelink may be applied in consideration of the availability of a radio access interface (e.g. Uu link) between a base station and a terminal in a 3GPP NG-RAN network (e.g. LTE (ng-eNB)/NR (gNB)). For example, the base station may provide the terminal with related settings for NR sidelink data transmission/reception, NR sidelink physical resource allocation, NR sidelink configuration (NR sidelink configuration, etc.) and other NR sidelink-related settings to the terminal, The sidelink may take this into account. Hereinafter, for convenience of description, ng-eNB or gNB on the NG-RAN network is described as a base station. In addition, the base station is not limited to only the ng-eNB or gNB on the NG-RAN network, and may be other types of wireless communication with the terminal. However, hereinafter, it will be described as a base station for convenience of description.

Next, the UE may operate based on the NR sidelink DRX (NR SL DRX) configuration. As an example, an NR SL DRX configuration may be configured in a terminal performing sidelink communication. That is, the DRX cycle and activation time are configured based on the NR SL DRX configuration between terminals performing data transmission/reception based on the sidelink, and sidelink communication may be performed based on this.

In addition, sidelink terminals may perform NR SL HARQ feedback based on the NR SL DRX configuration. Here, a cast type capable of NR SL HARQ feedback may be at least one of unicast and groupcast. That is, the broadcast type may not require NR SL HARQ feedback.

In addition, a common DRX cycle (hereinafter, COD) may be configured to enable minimal data transmission/reception between sidelink terminals in a resource pool in which the NR SL DRX configuration is configured by default. For example, the COD setting is set between terminals (e.g. per UE, per direction (link)-specific or per peer UEs unicast/groupcast), resource pool, QoS (Quality of Service) class (PC5 QoS Identifier, PQI), service type (e.g. PSID/ITS-AID) or LCH (Logical Channel) may be configured independently. In addition, an independent NR SL DRX configuration may be additionally configured in addition to the COD that all terminals can share. Here, the additional NR SL DRX configuration includes some inter-terminal (e.g. per UE, per direction (link)-specific or per peer UEs), resource pool, QoS class (PQI), service type (e.g. PSID/ITS-AID) or LCH Each can be configured independently.

That is, the common NR SL DRX configuration or the independent NR SL DRX configuration may be set based on at least one of Table 13 below or a combination thereof. In addition, the NR SL DRX configurations of Table 13 may be set to one or more numbers.

As an example, the NR SL DRX configuration described below may be applied to at least one or combinations thereof of Table 13 below, and is not limited to a specific configuration. In addition, the NR SL DRX cycle configuration may also be provided by one upper parameter included in the NR SL DRX configuration, and is not limited to the above-described embodiment.

[Table 13]

That is, the NR SL DRX configuration may be configured based on a combination of one or more of the configuration methods in Table 13, and the NR SL DRX configuration of Table 13 may be applied in the following matters.

The NR SL DRX configuration may be provided by the base station. As another example, the NR SL DRX configuration may be pre-configured. As another example, the NR SL DRX configuration may be set based on Tx centric in which the transmitting terminal (Tx terminal) provides the NR SL DRX configuration to the receiving terminal (Rx terminal). As another example, the NR SL DRX configuration may be set based on Rx centric in which the receiving terminal determines the NR SL DRX configuration and delivers it to the transmitting terminal. As another example, the NR SL DRX configuration may be set through negotiation between terminals. Specifically, when a unicast session connection between terminals exists, the NR SL DRX configuration may be determined through negotiation between the transmitting terminal and the receiving terminal, through which the transmitting terminal and the receiving terminal are based on the same NR SL A DRX operation may be performed.

That is, the NR SL DRX configuration may be configured by various schemes, and is not limited to a specific scheme. As an example, Table 14 may be signaling options for the NR SL DRX configuration, through which the NR SL DRX configuration may be indicated.

[Table 14]

When the NR SL DRX configuration is configured in the terminal, the terminal may determine whether to report the PC5 DRX parameter to the base station. Terminals performing sidelink communication may determine who sets the DRX pattern first, and determine whether to report the information to the base station. As described above, since the base station can provide various configuration information related to sidelink to the terminal, there is a need to report the NR SL DRX configuration to the base station. In consideration of the above, the terminal may determine whether to report the PC5 DRX parameter to the base station.

In addition, as an example, the SL DRX active time (SL DRX active time) is transmitted through a Physical Sidelink Control Channel (PSCCH).

It may include time to monitor SCI (Sidelink Control Information). In addition, the SL DRX activation time is additionally transmitted through the PSSCH (Physical Sidelink Shared Channel).

It may include time to monitor SCI (PSSCH).

As another example, the activation time may include a periodic resource or a time domain resource allocation for each TB (Transport Block). As another example, the activation time may include a time in which SL HARQ feedback corresponding to PSSCH reception is transmitted through a Physical Sidelink Feedback Channel (PSFCH). As another example, the activation time may include a time for receiving the SL HARQ feedback corresponding to the PSSCH transmission through the PSFCH. That is, the activation time may include a time required for activation of the terminal for sidelink transmission, and is not limited to the above-described embodiment.

As a specific example, the terminal may be configured to perform sidelink transmission only in an active time and not perform sidelink transmission in an inactive time. Also, as an example, sidelink transmission may be possible in both an activation time and an inactive time.

When the sidelink transmission is possible only during the activation time, power consumption may be reduced because the terminal performs transmission only during the activation time, but there may be a limit to efficient resource utilization due to a high congestion level. On the other hand, when sidelink transmission is possible at both the activation time and the inactivation time, power consumption of the terminal may increase. Accordingly, it is possible to set whether the sidelink transmission is possible only at the activation time or both at the activation time and the deactivation time in consideration of the terminal situation.

Also, as an example, the NR SL DRX time unit may be defined as an absolute physical time unit (i.e. ms). As another example, the NR SL DRX time unit may be defined as a constant time value based on a logical slot. That is, the NR SL DRX time unit may be defined based on a logical slot without affecting the TDD UL-DL configuration. Here, the logical slot may refer to slots configured as a sidelink resource pool. The NR SL DRX related timer and time unit may be set based on the logical slot, and the time based on the following logical slot may be converted into an absolute time based on Equation 3 below.

in Equation 3

is the NR SL DRX cycle (

) is the number of sidelink slots corresponding to ms units,

is the ms value of the NR SL DRX cycle, and N may be the number of sidelink slots existing within 20 ms (Common TDD-UL-DL configuration). That is, based on Equation 3 below, logical slots may be converted into absolute time units in ms units.

[Equation 3]

A DRX resource pool in consideration of the NR SL DRX operation may be configured. As an example, a dedicated resource pool for transmission and reception of NR SL DRX terminals may be configured as the DRX resource pool. As another example, the DRX resource pool is not separated (segmentation), and may be determined by defining some time resources in the general resource pool for PSCCH monitoring. In addition, in order to avoid resource pool separation, a UE configured with NR SL DRX in an existing resource pool may also operate.

Also, as an example, parameters as shown in Table 15 below may be provided to the MAC layer to a sidelink terminal in which the NR SL DRX configuration is basically configured in the RRC layer. Here, the parameters of Table 15 may be set in consideration of the DRX parameter (Table 11) for the Uu link.

[Table 15]

In addition, as shown in Table 13 above, the DRX parameters are inter-terminal (e.g. per UE, per direction (link)-specific or per peer UEs unicast/groupcast), resource pool, QoS (Quality of Service) class (PC5 QoS Identifier, PQI), service type (e.g. PSID/ITS-AID), LCH (Logical Channel), or SL Grant (SL HARQ process) may be configured by a combination of at least one or more, as described above. Hereinafter, for convenience of description, the NR SL DRX configuration is referred to as a DRX process, but the name is not limited thereto.

Here, one or more NR SL DRX groups may be configured including at least some or all of the parameters of Table 15 according to the configuration of the RRC layer. Each NR SL DRX group may independently set parameter values included in the corresponding NR SL DRX group. As an example, some parameters may not be included in the configured NR SL DRX group and may be applied in common.

In addition, the Uu DRX group and the SL DRX group may be configured independently. However, as an example, some parameters may be set in common between the Uu DRX group and the SL DRX group. In addition, some parameters between the Uu DRX group and the SL DRX group may be set and adjusted in consideration of the Uu DRX operation and the SL DRX operation.

Specifically, a sidelink on duration timer (SL onDuration Timer) and a sidelink inactivity timer (SL inactivity timer) may be set for each NR SL DRX group. Here, the NR SL DRX group may be a group using an NR SL DRX configuration independent of each other. For example, the NR SL DRX group may apply an independent NR SL DRX timer setting for each target QoS class (PQIs or set of PQIs), cast type, resource pool, or SL grant.

On the other hand, as an example, the sidelink HARQ RTT timer and the sidelink retransmission timer may all be applied as a common value regardless of the NR SL DRX group. Alternatively, an independent sidelink HARQ RTT timer and/or sidelink retransmission timer value for each NR SL DRX group may also be applied. However, this is only one example, and the common NR SL DRX parameter setting and the independent NR SL DRX parameter setting may be configured differently and is not limited to the above-described embodiment.

In consideration of the above, common NR SL DRX parameter setting or independent NR SL DRX parameter setting may be possible based on all possible combinations of all NR SL DRX parameter configurations configurable in the RRC layer. not limited

As another example, the NR SL DRX group setting may be independently configured for a unicast PC5 connection (UC). In addition, the NR SL DRX group setting may be independently configured for a groupcast (GC). In addition, the NR SL DRX group setting may be independently configured for broadcast (Broadcast, BC). In addition, a common NR SL DRX configuration may be provided for at least one of broadcast, groupcast, and unicast prior to PC5 connection establishment. In addition, independent NR SL DRX configurations may be included for each QoS class, service type, LCH or a set thereof within a common NR SL DRX configuration. That is, in the case of optimizing NR SL DRX between two terminals, such as unicast, a common NR SL DRX configuration for at least one of a cast type, a QoS class, a service type, and an LCH is provided to the NR SL DRX terminal. can be

Hereinafter, downlink synchronization and uplink synchronization in the NR system will be described.

The synchronization signal block SSB may include a synchronization signal (SS) and a physical broadcast channel (PBCH). The SS may include a Primary SS (PSS) and a Secondary SS (SSS), and the PBCH may include a PBCH DeModulation Reference Signal (DMRS) and PBCH data.

Referring to FIG. 8 , one SSB may be defined as 4 OFDM symbol units in the time domain and 240 subcarriers (or REs) in the frequency domain. PSS may be transmitted in the first symbol, and SSS may be transmitted in the third symbol. The PBCH may be transmitted in the second, third, and fourth symbols. In the third symbol, the SSS may be positioned to be spaced apart from the PBCH by a guard period in 127 subcarriers in the middle, and the PBCH may be positioned in the low frequency and high frequency directions in the remaining subcarriers. In the time domain, the SSB may be transmitted based on a predetermined transmission pattern.

In the initial cell search step, the UE may detect the PSS and the SSS included in the SSB transmitted from the base station to perform downlink synchronization with the corresponding base station. Accordingly, the terminal may receive system information, etc. transmitted from the base station through the downlink channel.

In order for the terminal to successfully perform uplink transmission to the base station, uplink synchronization is required. The terminal may attempt uplink transmission to the base station through a random access procedure even in a state where uplink synchronization is not matched, and the base station provides time alignment information (eg, TAC) to the corresponding terminal based on the uplink signal from the terminal. ) can be provided. The time alignment information may be included in a random access response (RAR) or a MAC control element (CE).

It is shown that one MAC PDU (Protocol Data Unit) is composed of one or more MAC subPDUs in FIG. 9( a ). One MAC subPDU may include only a MAC subheader, include a MAC subheader and a MAC Service Data Unit (SDU), include a MAC subheader and a MAC CE, or include a MAC subheader and padding. have.

9(b) to 9(d) show exemplary formats of a MAC subheader.

FIG. 9(b) shows a MAC subheader format used in the case of a fixed-length MAC CE, MAC SDU, and padding. For example, the format of the MAC subheader may be defined as 1 octet (or 8 bits) including the R and LCID fields. The 1-bit R field indicates a reserved field and its value may be 0. A 6-bit LCID (Logical Channel Identifier) field indicates a logical channel identifier field. For example, when the value of the LCID field is 62, TAC may be indicated in downlink, and UE Contention Resolution Identity may be indicated in uplink.

9( c ) and 9 ( d ) show MAC subheader formats used in the case of variable MAC CE and MAC SDU. For example, the format of the MAC subheader may be defined with a size of 2 octets or 3 octets including R, F, LCID and L fields. The 1-octet or 2-octet L field may have a value indicating the variable length of the MAC SDU or MAC CE in octets (or bytes). The 1-bit F field may have a value indicating the size of the L field. For example, when the value of the F field is 0, it may mean that the size of the L field is 1 octet, and when the value of the F field is 1, it may mean that the size of the L field is 2 octets.

In this way, one LCID, one L, and one F field may be included in one MAC subheader.

In the terminal autonomous resource selection mode (or mode 2), the terminal may determine the slots in which the PSCCH for SA and the PSSCH for data will be transmitted by sensing (sensing).

[Table 16]

10 illustrates a method of selecting slots for transmitting a control channel and a data channel by sensing from a resource pool for transmission of a control channel (PSCCH) and a data channel (PSSCH) associated therewith.

On a sensing window corresponding to the section from "TTI m-a" to "TTI m-b", the terminal may determine the resource occupied and used by another terminal through sensing. Based on this, the terminal may select a resource from among the remaining resources other than the resource to be used or occupied by the other terminal from among the resources belonging to the resource pool. That is, sensing a specific resource for resource selection may include referencing whether a resource corresponding to the specific resource is occupied or used within a sensing window (that is, at a previous point in time based on the specific resource). . Since the sidelink resource allocation may have a periodic characteristic, a sensing target resource in the resource pool (or selection window) may correspond to a sensing reference resource in the previous sensing window. For example, if a sensing reference resource in a sensing window corresponding to a sensing target resource in the resource pool (or selection window) is used by another terminal, the corresponding sensing target resource in the resource pool (or selection window) is used by the other terminal It can be assumed that it is likely to be occupied or used. Therefore, it is possible to select a transmission resource from among the remaining resources excluding the corresponding resource from the resource pool. Accordingly, the terminal may perform transmission of a control channel and/or a data channel on the selected resource.

In addition, when the terminal determines the resource selection (selection) / reselection (reselection), "TTI m" corresponding to the arrival of the corresponding TB (that is, the TB generated in the upper layer of the terminal arrives at the physical layer) corresponds to time.

Specifically, it can be expressed as a=T ₀ , and it can be expressed as b=T _proc,0 . Here, the length of the sensing window corresponding to the section from “TTI ma” to “TTI mb” may be expressed as a-b+1. For example, a=T ₀ =1000·2 ^u may be, and b=T _proc,0 ∈{1, 2, 3, 4} (eg, 1, u= when u=0) 2 when 1, 3 when u=2, 4 when u=4). When T _proc,0 =1, the sensing window corresponds to the "TTI m-1000·2 ^u " slot to the "TTI m-1" slot, and the length of the sensing window ("a-b+1=T ₀ -T _proc,0 +1=T ₀ -1+1=T ₀ ") corresponds to 1000·2 ^u slots, so it may be 1000 ms. In the above example, T ₀ is 1000 ms corresponding to 1000·2 ^u slots, but it is not limited thereto, and 1100 ms or 100 ms is also possible. Here, T ₀ is (pre-)configured to one of the values mentioned above, and T _proc,0 = 1, 2, 3 or 4, a fixed value can be used. have.

"TTI m+c" is a TTI for transmitting SA#1 (first SA (first SA)) (or a slot for transmitting SA#1 (first SA) when one TTI corresponds to one slot) may correspond to "TTI m+d" is a TTI (or one TTI is one TTI) for initial transmission of TB#1 (first TB (first TB)) indicated by SA#1 (first SA). If it corresponds to the slot, it may correspond to TB#1 (the slot in which the first TB is first transmitted). "TTI m+e" is a TTI (or when one TTI corresponds to one slot) for retransmission of TB#1 (first TB) that is transmitted as indicated by SA#1 (first SA). It may correspond to TB#1 (slot for retransmitting the first TB).

In the example of FIG. 10, since it is considered that SA and data are transmitted in the same slot in V2X, c=d.

Here, after the initial transmission in "TTI m+c", only retransmission in "TTI m+e" is mentioned, but retransmission can be performed up to three times by the N _max value. For example, when N _max is 1, only the first transmission in "TTI m+c" may exist. When N _max is 2, there may be an initial transmission in “TTI m+c” and a retransmission in “TTI m+e”. If N _max is 3, there may be an initial transmission in “TTI m+c”, a retransmission in “TTI m+e”, and a retransmission in “TTI m+f” although not shown.

"TTI m+c'" is a slot for transmitting TTI (or, when one TTI corresponds to one slot, SA#2 (second SA)) transmitting SA#2 (second SA) ) may be applicable. "TTI m+d'" is the TTI (or one TTI corresponds to one slot) that initially transmits TB#2 (second TB (second TB)) that is transmitted as indicated by SA#2 (second SA) In this case, it may correspond to TB#2 (slot for first transmitting the second TB). "TTI m+e'" is a TTI that retransmits TB#2 (second TB) transmitted as indicated by SA#2 (second SA) (or TB# when one TTI corresponds to one slot) 2 (slot for retransmitting the second TB)).

In the example of FIG. 10, since it is considered that SA and data are transmitted in the same slot in V2X, c'=d'.

Here, as shown in Table 16, T ₁ ≤c≤T ₂ may be, T ₁ ≤ _proc,1 , T ₂

T _2,min . At this time, when u=0 (ie, when SCS is 15 kHz), T _proc,1 may be fixed to a value corresponding to three slots. Meanwhile, u=1, 2, 3 (ie, when SCS is 30 kHz, 60 kHz, and 120 kHz, respectively), T _proc,1 may be fixed to a value corresponding to 5, 9, and 17 slots, respectively. In addition, T _2,min is 5·2 ^u ,10·2 ^u orIt may be (pre)-set to a value corresponding to 20·2 ^u slots.

In addition, the "ec" value corresponding to the interval between the initial transmission and the retransmission of the same TB may be indicated as a value corresponding to 0, 1, 2, ..., 31 slots through the SCI. If the value is 0, it means that there is no retransmission after the initial transmission, and if the value is N _{retransmission} ∈ {1, 2, ..., 31}, N _{retransmission} slots after the It may mean that there is a retransmission.

More specifically, resources for initial transmission and retransmission of the same TB may be defined within the W section, where W corresponds to 32 slots. That is, within the W section corresponding to 32 slots from the slot "TTI m+c" corresponding to the first transmission to "TTI m+c+31" including it, after the first transmission according to the N _max value mentioned above 0, 1, or 2 retransmissions are possible. Specifically, in which slots within 32 slots each retransmission is performed, it may be indicated through SCI. If N _max = 2, as mentioned above, retransmission in "TTI m+e" after N _{retransmission} ∈{1, 2, ..., 31} slots from "TTI m+c" This is possible.

On the other hand, it can be expressed as d'=d+P*j (c'=c+P*j because c=d and c'=d'), and thus d'-d=c'-c=P*j can be expressed as Here, P means a resource reservation interval.

The P value may be determined by higher layer signaling. In this case, the P value may be one of values corresponding to 0, 1, 2, ..., 99, 100, 200, 300, ..., 1000 ms. In the transmitting terminal, the P value may be expressed as P _{rsvp_TX} , and in the receiving terminal, the P value may be expressed as P _{rsvp_RX} . At this time, P _{rsvp_TX} and P _{rsvp_RX} are ms-unit values, and when these are converted into slot-unit logical values (logical vlaue), they may be expressed as P` _{rsvp_TX} and _{P` rsvp_RX} .

And, j is set by the network for each carrier (or band) used for V2X within the range of [0, 1, ..., 10] or to be pre-configured (carrier-specific network configuration or pre-configuration) can In addition, one value among the values selected for j may be selected and indicated through the “Resource reservation” signaling field of the SCI included in the SA. Here, j = 0 means that the value of d' does not exist, that is, for the transmission of TB#2 (second TB), the resource is reserved after the TTI corresponding to "P*j" from "TTI m+d". means not

In Table 16, the meaning indicated by the SCI means that, in the case of the terminal autonomous resource selection mode (or mode 2), the transmitting terminal (or the first terminal) determines the corresponding parameter value by itself, and then, based on the determined value, to be used in Table 16 This means that the parameter is used, and the transmitting terminal (or the first terminal) instructs the receiving terminal (or the second terminal) through the SCI so that the receiving terminal (or the second terminal) can know the determined value.

As described above, the slot in which the SA is transmitted in the base station resource scheduling mode (or mode 1) is Ams from the slot in which the base station (eNodeB or gNodeB) transmits DCI (in this case, A=4, but not limited thereto) It is the first slot included in the set of resource candidates that can be used for V2X on the V2X carrier (or band) among the later slots. Here, information on a resource block that is a frequency axis resource used for SA transmission in a slot in which the SA is transmitted may be indicated through DCI.

In addition, in the base station resource scheduling mode (or mode 1), the DCI is information necessary for the terminal to transmit data in V2X communication, and also includes SCI-related content included in the SA, and the DCI is transmitted from the base station to the terminal do.

Here, the first terminal may determine the sidelink scheduling information based on the DCI information and generate the determined sidelink scheduling information as the first SCI and the second SCI. The first terminal may transmit the first SCI to the second terminal through the PSCCH, and the second SCI may be transmitted to the second terminal by using some of the PSSCH transmittable resources. The second terminal may identify a sidelink resource through which the first terminal intends to transmit sidelink data through the PSSCH based on the first and second SCIs received from the first terminal. The second terminal may receive sidelink data from the first terminal on the identified resource through the PSSCH.

On the other hand, in the terminal autonomous resource selection mode (or mode 2), the terminal itself determines the slot in which the SA is to be transmitted in the resource pool by sensing, and the frequency axis resource used for the SA transmission in the slot in which the SA is transmitted. A resource block may also be determined by the UE itself in the resource pool. Therefore, unlike the base station resource scheduling mode (or mode 1), in the terminal autonomous resource selection mode (or mode 2), the terminal determines the resource by itself, without separately receiving signaling fields related to resource scheduling indicated by being included in DCI. will do

In addition, in the terminal autonomous resource selection mode (or mode 2), the terminal itself determines the SCI-related content included in the SA as information necessary for the terminal to transmit data in V2X communication. Accordingly, unlike the base station resource scheduling mode (or mode 1), in the terminal autonomous resource selection mode (or mode 2), signaling fields related to SCI indicated by including DCI are not separately transmitted, and the terminal determines itself.

Here, the first terminal may autonomously determine the sidelink scheduling information and generate the determined sidelink scheduling information as the first SCI and the second SCI. The first terminal may transmit the first SCI to the second terminal through the PSCCH, and the second SCI may be transmitted to the second terminal by using some of the PSSCH transmittable resources. The second terminal may identify a sidelink resource through which the first terminal intends to transmit sidelink data through the PSSCH based on the first and second SCIs received from the first terminal. The second terminal may receive sidelink data from the first terminal on the identified resource through the PSSCH.

That is, the SCI included in the SA as information necessary for the terminal to transmit data is scheduled by the base station in the base station resource scheduling mode (or mode 1), and the terminal selects itself in the terminal autonomous resource selection mode (or mode 2). have. However, in both the base station resource scheduling mode (or mode 1) and the terminal autonomous resource selection mode (or mode 2), the terminal (the receiving terminal or the second terminal) that receives the data transmits the data (the transmitting terminal or the first terminal) ), since the SCI included in the SA is required to decode the data transmitted from Should be.

As described above, in V2X, in particular, a sensing-based resource selection method for V (Vehicle)-UE (User Equipment) is as described in FIG. 10 .

Unlike Vehicle to Vehicle (V2V) in which V-UE is considered, V2P (Vehicle to Pedestrian) transmitted by V-UE to P (Pedestrian)-UE (User Equipment) or P2V transmitted by P-UE to V-UE (Pedestrian to Vehicle)) may consider additional energy savings. That is, the V-UE may not consider the power limitation situation as a terminal belonging to the vehicle, but the P-UE is a pedestrian terminal with a limit of battery power, so it is required to consider the power limitation situation.

Therefore, for V-UE, a sensing-based resource selection method targeting all resources within a specific interval (eg, 1000 ms corresponding to the interval from “TTI m-a” to “TTI m-b”) full) sensing method) can be applied. On the other hand, for the P-UE, a sensing-based resource selection method targeting some resources within a specific section (eg, 1000 ms corresponding to the section from “TTI m-a” to “TTI m-b”) to reduce power consumption (hereinafter, a partial sensing method) is required.

On the other hand, when the P-UE transmits sidelink control information and data to the V-UE (this corresponds to the case of performing P2V communication, the V-UE such as a vehicle acquires information about the P-UE such as a pedestrian) to prepare for safety matters), but conversely, if the P-UE does not receive sidelink control information and data from the V-UE (this corresponds to the case of not performing V2P communication, A case in which the P-UE does not need to acquire information about the V-UE, such as a vehicle, in order to prepare for safety matters) may be considered. When considering a case for supporting devices without sidelink reception capabilities as described above, a random-based resource selection scheme (hereinafter, a random resource selection scheme) is also required for the P-UE.

Meanwhile, a partial sensing method needs to be applied as a resource selection method for a P-UE in consideration of power limitation, but a specific operation for this has not yet been defined. In addition, a specific configuration method has not yet been defined for the resource pool for the P-UE in consideration of the power limitation.

In addition, as for the resource selection method for the P-UE lacking the sidelink reception capability, the random resource selection method needs to be applied, but a specific operation for this has not been defined yet. In addition, a specific configuration method has not yet been defined for a resource pool for a P-UE lacking sidelink reception capability.

The resource pool for the partial sensing-based P-UE (specifically, the slot pool corresponding to the time domain resource) is based on the resource pool (specifically the slot pool corresponding to the time domain resource) for the full sensing-based V-UE. can be defined. That is, the entire sensing method and the partial sensing method differ only in the size of the sensing window, and complexity can be simplified by performing a similar sensing-based operation.

On the other hand, the resource pool for the P-UE based on random resource selection (specifically the slot pool corresponding to the time domain resource) is the resource pool for the V-UE based on the entire sensing (specifically the slot pool corresponding to the time domain resource) ) can be defined independently of When the resource pool (specifically, the slot pool corresponding to the time domain resource) for the P-UE is independently set, the performance of the P-UE compared to sharing the resource pool (specifically, the slot pool corresponding to the time domain resource) This can be increased. That is, the resource for the P-UE based on random resource selection is not affected by other resources (eg, the resource for the P-UE based on partial sensing and/or the resource for the V-UE based on the full sensing). There is an advantage that the performance of the P-UE can be increased by being independently configured without the need to do so.

On the other hand, the resource pool for the P-UE based on random resource selection (specifically, the slot pool corresponding to the time domain resource) is the resource pool for the V-UE based on the entire sensing (specifically, the resource pool corresponding to the time domain resource) It may be defined by sharing a slot pool). This is to prevent a decrease in resources available for V2V when configuring independent resources for P-UE, affecting the performance of V2V. In addition, since one pool is shared and used, there is an advantage that resources can be used more efficiently without wasting resources.

Here, a resource pool for a P-UE based on random resource selection (specifically a slot pool corresponding to a time domain resource) and a resource pool for a partial sensing based P-UE (specifically a slot pool corresponding to a time domain resource) can be distinguished from each other with orthogonality. This is to ensure that the resources used by the partial sensing-based P-UEs are not interfered with by the random resource selection-based P-UEs.

12 is a diagram illustrating a sidelink buffer status report (SL BSR) MAC control element to which the present disclosure can be applied. The transmitting terminal (Tx terminal) may transmit the maximum SL BSR MAC CE through the uplink shared channel. In this case, the SL BSR MAC CE of the MAC PDU may be identified through the LCID of the MAC subheader. For example, referring to FIG. 12 , the SL BSR MAC CE includes one destination index field, one LCG ID field, and one buffer for each logical channel group (LCG). It may include a buffer size field, and specific details may be as shown in Table 17 below.

[Table 17]

As an example, the existing NR SL (e.g. Rel. 16 NR Sidelink) was mainly developed to support V2X related to road safety services. NR SL is based on network coverage in-coverage (In coverage, IC) and out-of coverage (OoC), at least one of broadcast, groupcast, and unicast communication in an IC (In coverage) scenario can operate based on

However, in the new NR SL, sidelink improvement for commercial services as well as V2X and public safety services is required. To this end, in the evolved NR sidelink enhancement (NR SL), the NR SL DRX operation may be considered in order to reduce power consumption, as described above. For example, in the existing NR SL (e.g. Rel. 16 NR sidelink) system, the UE could operate based on the case of being always-on for sidelink operation in a state in which the battery is sufficient. However, in the new NR SL (e.g. Rel. 17 NR SL), in addition to V2X and public safety, functions required for vulnerable road users (VRU) such as pedestrians, cyclists, motorcycles and people with reduced mobility using commercial services there is a need to provide That is, in the new NR SL, a sidelink operation of terminals with limited power may be required, and there is a need to satisfy a requirement for this.

In consideration of the above, the new NR SL may support discontinuous reception (SL DRX) functions in sidelink broadcast, groupcast, and unicast. Through this, On- and Off-durations are set in the terminal, and the terminal may operate based on the configured NR SL DRX configuration. Here, a synchronization method for a terminal in which SL DRX is configured may be required. In addition, the terminal configured with SL DRX needs to perform synchronization with the terminal configured with DRX in the Uu link to operate.

A UE configured with SL DRX needs to operate in consideration of SL DRX when selecting a resource, and the following describes a problem occurring based on SL DRX and a solution therefor.

13 may be a sidelink operation scenario to which the present disclosure may be applied. As an example, in Scenario 1 and Scenario 2 of FIG. 13 , the transmitting terminals (Tx UE, 1313, 1323) and the receiving terminals (Rx UE, 1312, 1322) may perform SL communication. In this case, the receiving

terminals

1312 and 1322 may be in a state connected to the

base stations

1311 and 1321 , and may perform a Uu DRX operation to monitor the PDCCH transmitted from the base station based on a predetermined interval. That is, the receiving

terminals

1312 and 1322 may receive signals from the

base stations

1311 and 1321 for on-duration based on the Uu DRX cycle.

Here, as an example, SL DRX may be set as a method of reducing power consumption of the terminal. For example, if the SL DRX and Uu DRX of the

receiving terminals

1312 and 1322 are set to occur at the same time, the on-duration sections of the

receiving terminals

1312 and 1322 overlap, thereby reducing power consumption. That is, when the receiving

terminals

1312 and 1322 are connected to the

base stations

1311 and 1321 and perform Uu DRX in an RRC connected state, a PC5 link is established with the transmitting

terminals

1313 and 1323 so that SL DRX is also performed. can be performed simultaneously.

As a more specific example, FIG. 14 is a diagram illustrating a method in which on-durations of Uu DRX and SL DRX to which the present disclosure can be applied are aligned.

Referring to FIG. 14 , on-duration of Uu DRX and SL DRX of a receiving terminal may be aligned. Here, the Uu DRX of the receiving terminal may be configured to monitor the PDCCH during the on-duration period at every specific period based on the parameter set by the base station. As an example, although FIG. 14 describes a method for the UE to perform PDCCH monitoring in one slot, it may not be limited to the embodiment. That is, the on-duration period may be set differently. Also, as an example, in FIG. 14 , the Uu DRX cycle may be 10 slots and the SL DRX cycle may be 20 slots, but this is only one example, and other cycles may be configured without being limited thereto.

That is, as shown in FIG. 14 , the receiving terminal can simultaneously perform monitoring in the same section by arranging on-durations of Uu DRX and SL DRX, thereby reducing the monitoring time to reduce power consumption.

Hereinafter, a method of determining the SL DRX of the receiving terminal based on the above description will be described. For example, the SL DRX of the receiving terminal may be determined by the transmitting terminal. As a more specific example, the SL DRX of the receiving terminal may be determined by the transmitting terminal because it needs to be set in consideration of the service type, traffic pattern, QoS, etc. provided by the transmitting terminal. As another example, it may be possible for the receiving terminal to directly determine the SL DRX, and it is not limited to the above-described embodiment.

As another example, as terminals performing SL communication in which a PC5 link is established, a transmitting terminal or a receiving terminal may determine SL DRX with reference to assistance information of a counterpart terminal. In more detail, FIG. 15 is a diagram illustrating a method of configuring SL DRX based on assistance information to which the present disclosure can be applied.

Referring to FIG. 15 , a transmitting terminal 1510 may transmit an SL RRC reconfigurationSL message including SL DRX configuration (DRX-configSL) information to a receiving terminal 1520 . At this time, when the receiving terminal 1520 fails to set the SL DRX configuration based on the SL DRX configuration information, the receiving terminal 1520 sends an SL RRC reconfiguration failure (RRC reconfigurationfailureSL) message to the transmitting terminal 1510 through the receiving terminal ( 1520) may be transmitted. As another example, the receiving terminal 1520 may transmit assistance information of the receiving terminal 1520 to the transmitting terminal 1510 through a new RRC message.

Thereafter, the transmitting terminal 1510 may determine the SL DRX parameter based on the auxiliary information received from the receiving terminal 1520 . The transmitting terminal 1510 may change the SL DRX configuration based on the determined SL DRX parameter and transmit an SL RRC reconfiguration message including the modified SL DRX configuration (modified DRX-configSL) to the receiving terminal 1520 . Thereafter, the receiving terminal 1520 configures SL DRX based on the SL DRX configuration information included in the SL RRC reconfiguration message, and may transmit an SL RRC reconfigurationcompleteSL message to the transmitting terminal 1510 .

In this case, as an example, the auxiliary information of the receiving terminal received by the transmitting terminal may include Uu DRX configuration information of the receiving terminal or preferred DRX information of the receiving terminal. When the transmitting terminal sets SL DRX based on the received auxiliary information, the transmitting terminal may set the SL DRX of the receiving terminal in consideration of Uu DRX configuration information of the receiving terminal.

As an example, FIG. 16 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied sets SL DRX in consideration of a Uu DRX configuration of a receiving terminal. For example, in scenario 2 of FIG. 13 , the receiving terminal may be in an RRC connected state, and may be in a state in which Uu DRX is configured. Here, referring to FIG. 16 , the receiving terminal may perform PDCCH monitoring in the on-duration period to receive at least one of a UL grant, a DL grant, and an SL grant from a base station. In this case, in FIG. 16 , the Uu DRX cycle may be 10 ms, and the DRX start offset (drx-startoffset) may be set to 9. However, this is only an example, and may not be limited to the above-described conditions.

In this case, the receiving terminal may perform an operation of monitoring the PDCCH in a subframe after the DRX start offset based on the above-described Uu DRX configuration. In addition, the receiving terminal may perform PDDCH monitoring at regular intervals based on the DRX cycle after the DRX start offset. In this case, the receiving terminal may receive information on the DRX cycle and the DRX start offset from the base station through the RRC message. As an example, the DRX start offset may be set based on any one of the values in Table 18 below, but may not be limited thereto.

[Table 18]

In this case, since the Uu DRX of the receiving terminal may be a configuration between the receiving terminal and the base station, the transmitting terminal may not be able to recognize whether or not the Uu DRX of the receiving terminal is operating and configuration information. Accordingly, the receiving terminal may include the Uu DRX operation parameter information of the receiving terminal in assistance information and transmit it to the transmitting terminal. That is, the transmitting terminal may recognize the Uu DRX operation of the receiving terminal based on the Uu DRX operation parameter included in the auxiliary information of the receiving terminal, and may set the SL DRX of the receiving terminal through this.

Here, referring to FIG. 17 , the transmitting terminal may check the position of the subframe in which PC5 DTX is possible in consideration of the Uu DRX of the receiving terminal. In this case, the transmitting terminal may configure the receiving terminal by setting the SL DRX cycle based on at least one of a service type of a PC5 link, a traffic pattern, and QoS.

More specifically, referring to FIGS. 18 and 19 , the transmitting terminal may configure SL DRX of the receiving terminal to be performed in the same subframe as Uu DRX. As an example, the transmitting terminal may set the SL DRX cycle of the receiving terminal to 10 ms as in FIG. 17 to perform the SL DRX operation in a corresponding subframe based on the Uu DRX operation of the receiving terminal. That is, the transmitting terminal may set the SL DRX cycle to be the same as the Uu DRX cycle. In addition, the transmitting terminal may set the start offset of the SL DRX to be the same as the start offset of the Uu DRX. Through this, SL DRX of the receiving terminal may be performed in the same subframe as the subframe in which Uu DRX is performed. Here, the transmitting terminal may set the SL DRX cycle based on at least one of a traffic pattern and QoS. For example, if it is determined that the SL DRX operation of the receiving terminal does not need to be performed the same as Uu DRX in consideration of the traffic pattern and QoS, the transmitting terminal may set the SL DRX cycle to a multiple of the Uu DRX cycle.

As a more specific example, in FIG. 19 , the transmitting terminal may set the SL DRX cycle to 20 ms, which is twice the Uu DRX cycle. In this case, the transmitting terminal may set the SL DRX start offset to be the same as the DRX start offset for Uu DRX.

As another example, the transmitting terminal may set the SL DRX start offset based on the DRX start offset for Uu DRX based on the following equation. That is, since there are two subframes in which SL DTX configuration is possible within a 20ms SL DRX cycle, SL DRX can be selectively configured.

[Equation 4]

drx-startoffsetSL= drx-startoffset + drx-cycle × n (0~N-1)

Also, as an example, assistance information of the receiving terminal that the transmitting terminal receives may include Uu DRX related information or Uu DRX related parameters, as described above. In this case, the Uu DRX related information or the Uu DRX related parameter may include at least one of a system frame number (SFN), a DRX cycle, and a DRX start offset. For example, in consideration of a case in which the receiving terminal and the transmitting terminal are connected to different base stations and synchronization between the receiving terminal and the transmitting terminal is different, the Uu DRX related information may include SFN information. Through this, the transmitting terminal may set the SL DRX configuration of the receiving terminal. In this case, as an example, the transmitting terminal may set the SL DRX cycle and the SL DRX start offset in consideration of at least one of the PC5 traffic pattern and QoS, as described above.

Although the above-described method describes a method for the transmitting terminal to determine the SL DRX configuration of the receiving terminal, it is not limited thereto.

As an example, the receiving terminal may directly determine the SL DRX configuration with reference to the Uu DRX configuration configured from the base station. That is, the receiving terminal may determine the SL DRX cycle and the SL DRX start offset by itself. Thereafter, the receiving terminal may transmit information on the SL DRX configuration to the transmitting terminal. Here, as an example, since the synchronization between the transmitting terminal and the receiving terminal is different and traffic pattern or QoS information may be required, the transmitting terminal may transmit the SFN information, traffic pattern, and QoS information to the receiving terminal to match the synchronization. Through this, the receiving terminal can directly determine the SL DRX configuration and then transmit it to the transmitting terminal.

Also, as an example, in the above-mentioned bar, the subframe was described as ms, but it may be possible to apply it based on the slot. That is, the Uu DRX cycle and the DRX start offset may be set on a slot basis. In this case, the SL DRX cycle and the SL DRX start offset may be set according to corresponding slots based on the Uu DRX cycle and the Uu DRX start offset. In the above-mentioned bar, the subframe is used as a reference for convenience of description, but the present invention is not limited thereto and the same may be applied to a slot.

Next, the transmitting terminal operating based on mode 1 may require an operation in consideration of the SL DRX configuration. Here, the transmitting terminal is a terminal operating based on mode 1 and may operate based on base station scheduling. That is, the transmitting terminal operating based on mode 1 may be allocated from the base station without directly determining the resource used for SL communication. As an example, referring to FIG. 20A , in scenario 3, the transmitting terminal may be scheduled by the base station as a terminal operating based on mode 1. In this case, the transmitting terminal may monitor the PDCCH transmitted by the base station and receive the SL grant. At this time, the transmitting terminal decodes DCI format 3_0 (DCI format 3_0) scrambled with sidelink-radio network temporary identifier (SL-RNTI)/sidelink-configured scheduled-radio network temporary identifier (SL-CS-RNTI), and based on this Thus, resources for SL communication can be allocated. Here, as an example, DCI format 3_0 may include fields as shown in Table 19 below, but may not be limited thereto.

[Table 19]

As described above, the mode 1 terminal in which SL DRX is activated may be allocated resources from the base station. In this case, when a resource is allocated in a non-on-duration region based on SL DRX, the transmitting terminal may not be able to perform SL communication in the allocated resource. Therefore, in the case of a mode 1 terminal, SL DRX needs to be determined by the base station. As another example, the transmitting terminal transmits SL DRX information to the base station, and there is a need to allocate resources based on the SL DRX information.

More specifically, referring to FIG. 20 , a transmitting terminal may monitor a PDCCH based on Uu DRX and may be allocated a resource based on DCI format 3_0. In this case, the transmitting terminal may transmit 1st sidelink control information (SCI) to the receiving terminal in the indicated SL resource 2010 . However, the reception terminal 1 may not be able to monitor the 1st SCI because it is not in an on-duration state in a resource in which the 1st SCI is transmitted based on the SL DRX of the reception terminal 1 . Also, the reception terminal 2 may not be able to monitor the 1st SCI because it is not in an on-duration state in a resource in which the 1st SCI is transmitted based on the SL DRX of the reception terminal 2 .

Accordingly, the transmitting terminal operating on the basis of mode 1 may perform an SL DRX request and information report to the base station while the PC5 link is established. As another example, the transmitting terminal operating based on mode 1 may perform an SL DRX request and information report to the base station after the PC5 link is established.

As another example, the transmitting terminal may include information previously set by the base station. In this case, the transmitting terminal may set the SL DRX configuration based on previously set information, and may not be limited to the above-described embodiment.

As an example, FIG. 21 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied configures SL DRX of a receiving terminal.

Referring to FIG. 21 , the base station 2110 may transmit an RRCsetup message to the transmitting terminal 2120 . As another example, the base station 2110 may transmit an RRC reconfiguration message to the transmitting terminal 2120 . In this case, as an example, the RRC setup message or RRC reconfiguration message is a parameter for cell group configuration (CellgroupConfig), MAC-cell group configuration (MAC-CellGroupConfig) and DRX configuration (DRX-Config) in relation to the master cell group (masterCellGroup). It may include at least any one or more of.

Here, the RRC configuration message or the RRC reconfiguration message may further include SL DRX information. In this case, as an example, the SL DRX information may include information on a plurality of sets related to the SL DRX configuration. The transmitting terminal 2120 may perform PC5 RRC establishment with the receiving terminal 2130 . In this case, the transmitting terminal 2120 may determine the SL DRX configuration based on the SL DRX information received from the base station 2110 . As a more specific example, since the SL DRX information includes a plurality of sets related to the SL DRX configuration, the transmitting terminal may determine one of the plurality of sets related to the SL DRX configuration as the SL DRX configuration. Thereafter, the transmitting terminal 2120 may transmit an SL RRC reconfiguration message including the SL DRX configuration information to the receiving terminal 2130 . In this case, the receiving terminal 2130 may check whether the setting for the SL DRX configuration is possible. When the receiving terminal 2130 can set the SL DRX configuration, the receiving terminal may transmit an SL RRC reconfiguration complete message to the transmitting terminal 2120 to complete the SL DRX configuration. Also, as an example, when the receiving terminal 2130 is performing Uu DRX, the receiving terminal 2130 transmits assistance information to the transmitting terminal 2120 so that SL DRX and Uu DRX can be set to overlap as much as possible. can be transmitted This will be described later.

Thereafter, the transmitting terminal 2120 may transmit information on the configured SL DRX configuration to the base station 2110 . For example, the transmitting terminal 2120 may include the SL DRX configuration information in the SL terminal information (sidelinkUEinformatio) and transmit it to the base station 2110 . As described above, the base station 2110 may identify the destination terminal (ie, the reception terminal 2130) to which the SL DRX configuration is set, and may allocate resources for SL communication based thereon.

As another example, FIG. 22 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied configures SL DRX of a receiving terminal.

Referring to FIG. 22 , the base station 2210 may transmit an RRCsetup message to the transmitting terminal 2220 . Alternatively, the base station 2210 may transmit an RRC reconfiguration message to the transmitting terminal 2220 . In this case, as an example, the RRC setup message or RRC reconfiguration message is a parameter for cell group configuration (CellgroupConfig), MAC-cell group configuration (MAC-CellGroupConfig) and DRX configuration (DRX-Config) in relation to the master cell group (masterCellGroup). It may include at least any one or more of.

Here, the RRC configuration message or the RRC reconfiguration message may further include SL DRX information. In this case, as an example, the SL DRX information may be information about a single set related to SL DRX. The transmitting terminal 2220 may perform PC5 RRC establishment with the receiving terminal 2230 . In this case, the transmitting terminal 2220 may determine the SL DRX configuration based on the SL DRX information received from the base station. As a more specific example, the SL DRX information may be one set related to the SL DRX configuration. Accordingly, the transmitting terminal may determine the SL DRX based on one set related to the SL DRX configuration as the received SL DRX information. Thereafter, the transmitting terminal 2220 may transmit an SL RRC reconfiguration message including the SL DRX configuration information to the receiving terminal 2230 . In this case, the receiving terminal 2230 may check whether SL DRX can be performed based on the SL DRX configuration received from the transmitting terminal 2220 . When the receiving terminal 2230 can perform SL DRX, the receiving terminal 2230 may transmit an SL RRC reconfiguration complete message to the transmitting terminal 2220 to complete the SL DRX setup. Also, as an example, when the receiving terminal 2230 is performing Uu DRX, the receiving terminal 2230 transmits assistance information to the transmitting terminal 2220 so that SL DRX and Uu DRX can be set to overlap as much as possible. can be transmitted This will be described later.

Thereafter, the transmitting terminal 2220 may transmit the SL DRX configuration information to the base station 2210 by including the SL DRX configuration information in the SL terminal information (sidelinkUEinformatio). Through the above description, the base station 2210 may identify the destination terminal (ie, the receiving terminal 2230) to which the SL DRX configuration is set. As another example, the SL terminal information may include information on whether SL DRX is enabled in the reception terminal 2230 . That is, the base station 2210 may check SL DRX enable or disable information of the receiving terminal 2230 based on the SL terminal information.

As another example, the SL DRX information transmitted by the base station 2210 to the transmitting terminal 2220 may be a fixed value in consideration of at least one of a destination ID, QoS, and a traffic pattern. In this case, when the SL DRX information is a fixed value, the transmitting terminal 2220 may not report the SL DRX configuration determined through the SL terminal information because the SL DRX configuration configurable to the receiving terminal 2230 is one value. That is, the base station 2210 may know the SL DRX configuration of the receiving terminal 2230 without a report from the transmitting terminal 2220 , and may recognize the on-duration interval of the receiving terminal 2230 .

As another example, FIG. 23 is a diagram illustrating a method in which a transmitting terminal to which the present disclosure can be applied configures SL DRX of a receiving terminal.

Referring to FIG. 23 , the base station 2310 may transmit an RRCsetup message to the transmitting terminal 2320 . Alternatively, the base station 2310 may transmit an RRC reconfiguration message to the transmitting terminal 2320 . In this case, as an example, the RRC setup message or RRC reconfiguration message is a parameter for cell group configuration (CellgroupConfig), MAC-cell group configuration (MAC-CellGroupConfig) and DRX configuration (DRX-Config) in relation to the master cell group (masterCellGroup). It may include at least any one or more of. Here, the RRC configuration message or the RRC reconfiguration message may further include SL DRX information. The transmitting terminal 2320 may perform PC5 RRC establishment with the receiving terminal 2330 . At this time, the transmitting terminal 2320 is based on at least one of the SL DRX information (e.g. multiple set or single set) received from the base station 2310 and the pre-configuration SL-DRX information (pre-configuration SL-DRX info) SL DRX configuration can be determined. Thereafter, the transmitting terminal 2320 may transmit an SL RRC reconfiguration SL message including SL DRX configuration information to the receiving terminal 2330 . Through this, the receiving terminal 2330 may check the SL DRX configuration.

However, as described above, the receiving terminal 2330 must configure SL DRX based on at least one of Uu DRX and preferred PC5 DRX information of the receiving terminal 2330 to reduce power consumption. Accordingly, the receiving terminal 2330 may reject the SL DRX configuration of the transmitting terminal 2320 and transmit assistance information to the transmitting terminal 2320 . In this case, the auxiliary information may include at least one of Uu DRX information and preferred PC5 DRX information of the receiving terminal 2330 .

In this case, as an example, the transmitting terminal 2320 configures SL DRX through pre-configured/dedicated configuration SL-DRX info based on the auxiliary information received from the receiving terminal 2330 . can be determined whether or not At this time, when the transmitting terminal 2320 determines the SL DRX configuration, the transmitting terminal 2320 may transmit an SL RRC reconfiguration (RRCreconfigurationSL) message including the determined SL DRX configuration information to the receiving terminal 2330 .

On the other hand, when the transmitting terminal 2320 does not determine the SL DRX configuration, the transmitting terminal 2320 may report auxiliary information to the base station 2310 . As an example, the auxiliary information may include at least one of Uu DRX information and preferred PC5 DRX information of the receiving terminal 2330 . Thereafter, the base station 2310 may determine the SL DRX configuration in consideration of the received auxiliary information, and transmit an RRC reconfiguration message including the determined SL DRX configuration information to the transmitting terminal 2320 . As another example, the base station 2310 may transmit new SL DRX information to the transmitting terminal 2320 in consideration of the received auxiliary information. Here, the new SL DRX information may be determined based on at least one of a traffic pattern and a packet delay budget (PDB). As an example, the new SL DRX information may include at least one of SL DRX cycle and SL DRX-startoffset candidate set information based on a traffic pattern and PDB.

As an example, the base station 2310 may determine a range of an SL DRX cycle that can be determined according to a traffic pattern (e.g., Traffic pattern ‘A’), and may determine SL DRX cycle information based thereon. In addition, when the SL DRX cycle is determined, SL DRX start offset information may be determined based on the SL DRX cycle. As a more specific example, when the SL DRX cycle is 20 ms and the number of SL slots is 12 within 20 ms, the SL DRX start offset information may be set to a value of 0 to 11, but this is only one example. is not limited to

Thereafter, the transmitting terminal 2320 may check the SL DRX configuration, and transmit an SL RRC reconfiguration (RRCreconfigurationSL) message including the SL DRX configuration information to the receiving terminal 2330 . The receiving terminal 2330 may check whether the SL DRX operation is possible based on the SL DRX configuration, and if the SL DRX operation is possible, the receiving terminal 2330 may transmit an RRCreconfigurationcompleteSL message to the transmitting terminal 2320 .

Thereafter, the transmitting terminal 2320 may transmit the SL DRX configuration information to the base station 2310 by including the SL DRX configuration information in the SL terminal information (sidelinkUEinformatio). Through the above description, the base station 2310 may check the destination terminal (ie, the receiving terminal 2330) to which the SL DRX configuration is set. As another example, the SL terminal information may include information on whether SL DRX is enabled in the reception terminal 2330 . That is, the base station 2310 may check SL DRX enable or disable information of the receiving terminal 2330 based on the SL terminal information.

For example, the transmitting terminal 2320 receives the auxiliary information from the receiving terminal 2330 during the PC5-RRC establishment procedure and then forwards it to the base station 2310, but the transmitting terminal 2320 has the PC5-RRC establishment procedure. After completion, the auxiliary information may be received and transmitted to the base station 2310, and may not be limited to the above-described embodiment.

Next, a method in which a transmitting terminal operating based on mode 1 determines a destination terminal through a logical channel prioritization (LCP) procedure may be considered.

For example, in the existing SL system, since the on-duration may be performed in all subframes (or slots), the transmitting terminal could determine the destination terminal based on the LCP according to Table 20 below.

[Table 20]

However, when the SL DRX configuration is configured, the transmitting terminal needs to determine the destination terminal based on the LCP only in the on-duration period.

In this case, FIG. 24 is a diagram illustrating a method of setting a time gap to which the present disclosure can be applied. Referring to FIG. 24 , a time gap indicated in DCI format 3_0 that a transmitting terminal receives from a base station may indicate a 1st SCI transmission resource. That is, the transmitting terminal may receive DCI format 3_0 from the base station, decode it, and check time gap information. The transmitting terminal may transmit the 1st SCI to the receiving terminal through the 1st SCI transmission resource at a point separated by a time gap from the time when DCI format 3_0 is received. Here, the transmitting terminal may select the destination terminal associated with the LCH through the above-described LCP procedure. In this case, as an example, there is a possibility that the transmitting terminal performing the SL DRX operation selects the LCH associated with the destination terminal, not the on-duration in the corresponding 1st SCI transmission resource. That is, the transmitting terminal performs SL transmission using the resource allocated by the base station, but when the destination terminal is selected based on the LCP procedure, the case may not receive a signal unless the corresponding destination terminal is in the on-duration period. Therefore, the transmitting terminal needs to remove the LCH associated with the destination terminal, not the on-duration from the resource indicated by the time gap of DCI format 3_0, from the LCP procedure.

In consideration of the above, in the LCP procedure, a procedure for limiting the on-duration destination in the SL slot indicated by the time gap may be required. That is, when the base station implicitly refers to the destination terminal through the time gap, the transmitting terminal considers only the LCH associated with the destination ID, which is the duration on the SL slot indicated by the time gap, while performing the LCP procedure. (Implicit way)

As another example, the base station may explicitly indicate the destination ID to the transmitting terminal through DCI. (Explicit way) As another example, DCI format 3_0 includes a field indicating at least one of a destination ID and a destination ID list. may be included. As another example, a new DCI format is set, and the DCI format may include a field indicating at least one of a destination ID and a destination ID list, and is not limited to the above-described embodiment. In this case, the transmitting terminal may select the LCH associated with the indicated destination ID without performing the LCP procedure. As another example, when the transmitting terminal receives the destination ID list, the transmitting terminal may perform the LCP procedure only on the LCH associated with the destination ID based on the destination ID list index. Here, the destination ID index list (Destination ID list index) may be an index grouped in advance based on at least one of QoS and traffic patterns between the transmitting terminal and the base station.

As a more specific example, a case in which 32 destinations are grouped based on 4 QoS may be considered. In this case, the destination list index may be set to 2 bits to indicate each group, and may indicate one list index out of four. The transmitting terminal may perform the LCP procedure on the LCH associated with the destination included in the destination list indicated by the destination list index.

In this case, as an example, the field for the destination ID included in the DCI format may be a “destination indicator, and may be set to 5 bits based on the “SL-destinationIdentity” parameter. However, this is only an example, and is not limited to the above-described names or bits.

Also, as an example, the field for the destination ID list may be a “destination list index”. In this case, the “destination list index” may be determined between the base station and the transmitting terminal based on at least one of QoS and traffic patterns, as described above.

As another example, as described above, a time resource indication for SCI transmission may be performed based on a time gap of DCI. In this case, as an example, the time gap may have 8 lists with 3 bits. Also, as an example, 1 to 32 slot offsets may be indicated based on the time gap table, and through this, resources for SCI transmission may be determined. Based on the above, the terminal

Thereafter, 1st SCI may be transmitted in the first sidelink slot.

At this time, as an example, referring to FIG. 25 , Uu DRX may be determined with a period of 32 ms or more. In this case, when the PDB and Uu DRX cycles are greater than 32 ms, DCI format 3_0 may not indicate the on-duration resource of the receiving terminal. In FIG. 25 , the base station may perform scheduling only up to slot n in the time resource 2510 in which the transmitting terminal receives the DCI format through DCI. Here, when the on-duration of the receiving terminal exists in slots 2520 and 2530 after slot n, the base station cannot perform resource scheduling in consideration of the on-duration of the receiving terminal through DCI.

In consideration of the above, it is necessary to set the slot offset value as the RRC parameter to the maximum value of the PDB or SL DRX cycle. As an example, the time gap of DCI format 3_0 may not need to be changed since there are 8 unicast links. On the other hand, the above-described slot offset value indicated by the time gap table may be set to the maximum value of the PDB or SL DRX cycle, and the slot offset value as an RRC parameter may be set as shown in Table 21 below, do not limit

[Table 21]

As another example, the terminal operating based on mode 2 may determine the SL DRX in consideration of the PDB. For example, a terminal operating based on mode 2 may mean a terminal that directly selects a resource without base station scheduling.

26 is a diagram illustrating a method of determining an SL DRX cycle to which the present disclosure can be applied. Referring to FIG. 26 , a terminal operating based on mode 2 may perform SL communication based on a transmittable candidate resource after a time n when sidelink data is generated in the physical layer. In this case, the transmittable candidate resource may be determined based on n+T1 and n+T2. Here, T1 may be determined based on terminal selection. For example, in FIG. 26 , T1 may be selected as two slots, but this is only one example and is not limited to the above-described embodiment.

Also, as an example, T2 may be set as PDB when PDB is smaller than T2min. On the other hand, when PDB is greater than T2min, T2 may be determined from T2min to PDB based on the UE implementation. That is, the T2 value may be a value determined in consideration of the PDB. In this case, the transmitting terminal operating based on mode 2 may also configure SL DRX. For example, when the receiving terminal is connected to the base station to monitor the PDCCH, the transmitting terminal may determine the SL DRX configuration in consideration of the Uu DRX operation of the receiving terminal. In this case, as an example, the transmitting terminal may determine the SL DRX configuration in consideration of the PDB. More specifically, in FIG. 26 , the transmitting terminal may transmit SL data based on candidate resources up to time n+T2. In this case, as described above, T2 may be determined in consideration of the PDB. Accordingly, if the SL DRX is determined without considering the PDB, the on-duration of the receiving terminal may not exist until the time T2, and the SL data transmission may fail. In consideration of the above, the transmitting terminal may determine the SL DRX configuration in consideration of the PDB.

As an example, FIG. 27 is a diagram illustrating an SL DRX configuration method applicable to the present disclosure. Referring to FIG. 27 , the transmitting terminal may configure SL DRX in consideration of the Uu DRX of the receiving terminal. In this case, as an example, the Uu DRX cycle may be 20 ms, and the SL DRX may also be set to 20 ms based on this. However, this is only one example, and may not be limited to the above-described embodiment. Here, when the PDB is 10 ms, the transmitting terminal operating based on mode 2 may select a resource between T1 and T2 for SL data generated at time n and perform transmission. In this case, the receiving terminal may be in an off-duration state between T1 and T2 based on SL DRX and Uu DRX. Therefore, the physical layer of the transmitting terminal may not be able to report the possible resource set to the MAC layer. As another example, the MAC layer of the transmitting terminal may not be able to select a resource from the reported resource set. That is, if the SL DRX configuration is determined without considering the PDB, a problem may occur that the receiving terminal does not have on-duration on the candidate resource.

In consideration of the above, the transmitting terminal may determine the SL DRX of the receiving terminal in consideration of the PDB. For example, if the SL DRX cycle of the receiving terminal is not set within the PDB, the transmitting terminal may not be able to transmit data to the receiving terminal from available resources after the time when the SL data is generated.

Here, as an example, when Uu DRX of the receiving terminal is not configured, the transmitting terminal may configure SL DRX in consideration of the PDB. However, if Uu DRX of the receiving terminal is configured, the transmitting terminal needs to set not only the PDB but also the Uu DRX to overlap as much as possible, which will be described later.

As an example, FIG. 28 is a diagram illustrating an SL DRX configuration method applicable to the present disclosure. Referring to FIG. 28 , a case in which the PDB is smaller than the Uu DRX cycle of the receiving terminal may be considered. That is, when the SL DRX configuration is set to overlap with the Uu DRX configuration, the receiving terminal may be in an off-duration state in the resource through which the transmitting terminal transmits SL data. Accordingly, when the Uu DRX cycle is greater than the PDB, the SL DRX configuration may be configured such that the transmitting terminal takes into account the Uu DRX configuration of the receiving terminal and the PDB and on-duration from additional resources for PSCCH monitoring. That is, the SL DRX configuration may be set based on the Uu DRX configuration, and the receiving terminal may be additionally configured for on-duration in consideration of a PDB smaller than the Uu DRX cycle.

As a more specific example, in FIG. 28 , it may be considered that the PDB is 10 ms and the Uu DRX cycle is 20 ms. However, this is only one example for convenience of description, and is not limited to the above-described embodiment. In the above-described case, the receiving terminal may monitor the PSCCH with at least a PDB period. In addition, the SL DRX configuration may be set to overlap with the PDCCH monitoring period of the receiving terminal in consideration of the Uu DRX configuration, thereby reducing power consumption. Here, the transmitting terminal may set the SL DRX cycle and the SL DRX start offset to configure the SL DRX of the receiving terminal. As an example, the SL DRX cycle may be set to be the same as the Uu DRX cycle. In this case, two SL DRX start offsets may be set in consideration of the PDB. For example, as in FIG. 28, “SL drx-startoffset 1” may be set to 9, and “drx-startoffset 2” may be set to 19, and based on this, the receiving terminal may be on-duration in the 19th subframe or slot. have. As another example, only one SL DRX start offset may be set, and the SL DRX cycle may be set smaller than the Uu DRX cycle in consideration of the PDB. For example, in FIG. 28 , the SL DRX cycle may be set to 10 ms, and the SL DRX start offset “SL drx-startoffset” may be set to 9.

As another example, the SL DRX cycle may be set smaller than the PDB, and the SL DRX start offset may be determined based on the Uu DRX start offset. As an example, the SL DRX start offset may be set as a modulo value of the Uu DRX start offset in consideration of the PDB as shown in Equation 5 below, and is not limited to the above-described embodiment.

[Equation 5]

sl-drx-startoffset = Uu-drx-startoffset modulo PDB

As another example, FIG. 29 is a diagram illustrating an SL DRX configuration method applicable to the present disclosure. Referring to FIG. 29 , a case in which the PDB is greater than the Uu DRX cycle may be considered. In this case, as an example, the transmitting terminal may receive auxiliary information including information on the Uu DRX cycle from the receiving terminal, and may recognize the Uu DRX cycle based thereon. In this case, the transmitting terminal may compare the PDB and the Uu DRX cycle, and recognize that the PDB is greater than the Uu DRX. As an example, in FIG. 29 , the Uu DRX cycle may be 20 ms and the PDB may be 20 ms or more. However, this is only one example and is not limited to the above-described embodiment. In this case, the SL DRX cycle may be set to 10 ms or 20 ms in consideration of the Uu DRX cycle. For example, in FIG. 29 , the SL DRX cycle is set to 20 ms, but is not limited thereto.

In addition, as described above, the terminal operating based on mode 2 may set the time point of T2 from T2min to PDB according to the implementation of the terminal. Here, as an example, when the SL DRX cycle is set to 20 ms based on the Uu DRX cycle, the UE may determine the T2 time point up to the PDB. More specifically, a case in which the T2 time point consists of n5 of the sl-selectionwindow (n1, n5, n10, n20) and the PDB is 10 ms may be considered. In this case, the terminal may determine a value from T2min to PDB according to the terminal implementation for T2 as before. However, when SL DRX is configured, the transmitting terminal may determine the SL DRX period to be 10 ms in consideration of the case where the PDB is 10 ms. In addition, it is necessary to determine the T2 value by the PDB rather than the value from T2min to the PDB. That is, the SL DRX period and the T2 time may be determined based on the PDB, and through this, an on-duration period of the receiving terminal may exist in the candidate resource. As described above, even if SL data is generated at an arbitrary point in time, the transmitting terminal may allow the on-duration period of the receiving terminal to be located between T1 and T2, and through this, SL data reception may be described.

30 is a flowchart illustrating an SL DRX configuration setting method to which the present disclosure can be applied. Referring to FIG. 30 , the transmitting terminal may transmit SL DRX configuration information to the receiving terminal. (S3010) For example, the SL RRC reconfiguration message may include the SL DRX configuration information and may be transmitted. Thereafter, the receiving terminal may determine whether to perform SL DRX configuration. Here, when the receiving terminal is connected to the base station and performing Uu DRX, the receiving terminal needs to set the SL DRX configuration in consideration of Uu DRX. Accordingly, the receiving terminal may transmit assistance information including Uu DRX configuration information to the transmitting terminal without performing SL DRX configuration. (S3020) Thereafter, the transmitting terminal may respond to the auxiliary information received from the receiving terminal. Based on the SL DRX configuration can be changed. For example, in the SL DRX configuration, the SL DRX cycle and the SL DRX start offset may be set so that the Uu DRX configuration and the on-duration interval overlap. Thereafter, the transmitting terminal may transmit the changed SL DRX configuration to the receiving terminal. (S3030) At this time, the receiving terminal may receive the changed SL DRX configuration and perform the SL DRX configuration based thereon. (S3040) That is , the receiving terminal may overlap Uu DRX and SL DRX, thereby reducing power consumption.

The base station device 3100 may include a processor 3120 , an antenna unit 3112 , a transceiver 3114 , and a memory 3116 .

The processor 3120 performs baseband-related signal processing and may include an upper layer processing unit 3130 and a physical layer processing unit 3140 . The upper layer processing unit 3130 may process an operation of a medium access control (MAC) layer, a radio resource control (RRC) layer, or a higher layer. The physical layer processing unit 3140 may process a physical (PHY) layer operation (eg, uplink reception signal processing, downlink transmission signal processing). The processor 3120 may control the overall operation of the base station device 3100 in addition to performing baseband-related signal processing.

The antenna unit 3112 may include one or more physical antennas, and when it includes a plurality of antennas, it may support multiple input multiple output (MIMO) transmission and reception. In addition, beamforming may be supported.

The memory 3116 may store information processed by the processor 3120 , software related to the operation of the base station device 3100 , an operating system, an application, and the like, and may include components such as a buffer.

The processor 3120 of the base station 3100 may be configured to implement the operation of the base station in the embodiments described in the present invention.

The terminal device 3150 may include a processor 3170 , an antenna unit 3162 , a transceiver 3164 , and a memory 3166 . For example, in the present invention, the terminal device 3150 may communicate with the base station device 3100 . As another example, in the present invention, the terminal device 3150 may perform sidelink communication with another terminal device. That is, the terminal device 3150 of the present invention refers to a device capable of communicating with at least one of the base station device 3100 and other terminal devices, and is not limited to communication with a specific device.

The processor 3170 performs baseband-related signal processing, and may include an upper layer processing unit 3180 and a physical layer processing unit 3190 . The higher layer processing unit 3180 may process the operation of the MAC layer, the RRC layer, or higher layers. The physical layer processing unit 3190 may process PHY layer operations (eg, downlink reception signal processing, uplink transmission signal processing, sidelink signal processing). The processor 3170 may control the overall operation of the terminal device 3150 in addition to performing baseband-related signal processing.

The antenna unit 3162 may include one or more physical antennas, and when it includes a plurality of antennas, it may support MIMO transmission/reception. In addition, beamforming may be supported.

The memory 3166 may store information processed by the processor 3170 , software related to the operation of the terminal device 3150 , an operating system, an application, and the like, and may include components such as a buffer.

The terminal device 3150 according to an example of the present invention may be associated with a vehicle. For example, the terminal device 3150 may be integrated into a vehicle, located in the vehicle, or located on the vehicle. Also, the terminal device 3150 according to the present invention may be a vehicle itself. Also, the terminal device 3150 according to the present invention may be at least one of a wearable terminal, an AV/VR, an IoT terminal, a robot terminal, and a public safety terminal. The terminal device 3150 to which the present invention can be applied is any type of interactive service that supports interactive services using sidelinks for services such as Internet access, service performance, navigation, real-time information, autonomous driving, safety and risk diagnosis. It may also include communication devices. In addition, any type of communication device that becomes an AR/VR device capable of a sidelink operation or a sensor and performs a relay operation may be included.

Here, the vehicle to which the present invention is applied may include an autonomous vehicle, a semi-autonomous vehicle, a non-autonomous vehicle, and the like. Meanwhile, although the terminal device 3150 according to an embodiment of the present invention is described as being associated with a vehicle, one or more of the UEs may not be associated with a vehicle. This is an example, and should not be construed as limiting the application of the present invention according to the described example.

Also, the terminal device 3150 according to an example of the present invention may include various types of communication devices capable of performing cooperation supporting an interactive service using a sidelink. That is, when the terminal device 3150 directly supports the interactive service by using the sidelink, it may be utilized as a cooperative device for supporting the interactive service using the sidelink.

In addition, various embodiments of the present disclosure may be implemented by hardware, firmware, software, or a combination thereof. For implementation by hardware, one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), general purpose It may be implemented by a processor (general processor), a controller, a microcontroller, a microprocessor, and the like.

The scope of the present disclosure includes software or machine-executable instructions (eg, operating system, application, firmware, program, etc.) that cause operation according to the method of various embodiments to be executed on a device or computer, and such software or and non-transitory computer-readable media in which instructions and the like are stored and executed on a device or computer.

The various embodiments of the present disclosure do not list all possible combinations, but are intended to describe representative aspects of the present disclosure, and matters described in various embodiments may be applied independently or in combination of two or more.

The above can be applied to various systems.

Claims

A sidelink communication method of a terminal in a wireless communication system, the method comprising:

establishing, by the first terminal, a PC5 link connection for unicast communication with the second terminal;

receiving, by the first terminal, assistance information from the second terminal based on the established PC5 link connection; and

Determining, by the first terminal, a sidelink discontinuous reception (SL DRX) configuration for the unicast communication based on the auxiliary information with the second terminal.
The method of claim 1,

The first terminal reports the received auxiliary information to the base station; further comprising a sidelink communication method.
3. The method of claim 2,

The first terminal is a terminal in which a radio resource control (RRC) connection is established based on the base station, and based on a mode in which a sidelink resource for sidelink communication is scheduled from the base station, the second terminal and A terminal for performing the sidelink communication, a sidelink communication method.
4. The method of claim 3,

receiving, by the first terminal, first SL DRX configuration information from the base station based on the RRC connection, and determining a first SL DRX configuration; and

Transmitting the first SL DRX configuration information to the second terminal through the established PC5 link connection; further comprising,

The auxiliary information is generated based on the capability of the second terminal, and the first terminal receives the auxiliary information generated based on the capability of the second terminal from the second terminal. .
5. The method of claim 4,

receiving, by the first terminal, second SL DRX configuration information from the base station based on the auxiliary information, and determining a second SL DRX configuration as the SL DRX configuration; and

The first terminal transmitting the second SL DRX configuration information to the second terminal; further comprising a sidelink communication method.
The method of claim 1,

The auxiliary information includes preferred SL DRX configuration information of the second terminal.
7. The method of claim 6,

The second terminal is a terminal in which RRC connection with the base station is established,

The auxiliary information includes the preferred SL DRX configuration information configured in consideration of Uu DRX configuration information of the second terminal and the base station based on the established RRC connection.
A first terminal performing sidelink communication in a wireless communication system, comprising:

transceiver; and

processor; including;

The processor is

Establishing a PC5 link connection for unicast communication with the second terminal,

receiving assistance information from the second terminal through the transceiver based on the established PC5 link connection; and

determining an SL DRX configuration for the unicast communication based on the auxiliary information.
9. The method of claim 8,

The processor is

The terminal reports the auxiliary information received through the transceiver to the base station.
10. The method of claim 9,

The first terminal is a terminal in which an RRC connection is established based on the base station, and is a terminal that performs sidelink communication with the second terminal based on a mode in which a sidelink resource for sidelink communication is scheduled from the base station , terminal.
11. The method of claim 10,

The processor is

receive first SL DRX configuration information from the base station through the transceiver based on the RRC connection, determine a first SL DRX configuration, and

Transmitting the first SL DRX configuration information to the second terminal through the transceiver based on the established PC5 link connection,

The auxiliary information is generated based on the capability of the second terminal, and the first terminal receives the auxiliary information generated based on the capability of the second terminal from the second terminal.
12. The method of claim 11,

The processor is

receive second SL DRX configuration information from the base station through the transceiver based on the auxiliary information, and determine a second SL DRX configuration as the SL DRX configuration; and

The terminal transmits the second SL DRX configuration information to the second terminal through the transceiver.
9. The method of claim 8,

The auxiliary information includes preferred SL DRX configuration information of the second terminal, the terminal.
14. The method of claim 13,

The second terminal is a terminal in which RRC connection with the base station is established,

The auxiliary information includes the preferred SL DRX configuration information set in consideration of the Uu DRX configuration information of the second terminal and the base station based on the established RRC connection.