KR20220018909A - Method and apparatus for coordinating and allocating sidelink resource - Google Patents

Abstract

Disclosed are a method for coordination and allocation of sidelink resources and a device thereof are disclosed. An operation method of a transmitting terminal comprises the following steps of: receiving resource coordination information; selecting a resource for sidelink communication based on the resource coordination information; and transmitting data to one or more receiving terminals by using the selected resource.

Description

Method and apparatus for coordination and allocation of sidelink resources

The present invention relates to a sidelink communication technique in a communication system, and more particularly, to a technique for coordinating and allocating sidelink resources.

For processing of rapidly increasing wireless data, a frequency band (eg, 6 GHz) higher than a frequency band (eg, a frequency band of 6 GHz or less) of a long term evolution (LTE) communication system (or LTE-A communication system) A communication system (eg, a new radio (NR) communication system) using the above frequency bands) is being considered. The NR system may support a frequency band of 6 GHz or less as well as a frequency band of 6 GHz or higher, and may support various communication services and scenarios compared to the LTE system. In addition, the requirements of the NR system may include enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), and the like.

Sidelink communication may be performed in the NR system. Sidelink communication may be performed based on mode 1 or mode 2. When mode 1 is used, sidelink communication may be performed using a resource scheduled by the base station. When mode 2 is used, sidelink communication may be performed using a resource selected by the terminal. In this case, if the same resource is selected between terminals, sidelink communication may collide. A method is needed to solve these problems.

An object of the present invention to solve the above problems is to provide a method and apparatus for adjusting and allocating sidelink resources.

In order to achieve the above object, a method of operating a transmitting terminal according to a first embodiment of the present invention includes the steps of: receiving resource coordination information; selecting a resource for sidelink communication based on the resource coordination information; and and transmitting data to one or more receiving terminals using a resource, wherein the resource coordination information is one of preferred resource information and non-preferred resource information for the sidelink communication.

The method of operating the transmitting terminal may further include receiving an indicator indicating that the resource coordination information is the preferred resource information or the non-preferred resource information.

When the resource coordination information is the preference resource information, the resource for the sidelink communication may be selected within a first resource region indicated by the resource coordination information.

When the resource coordination information is the non-preferred resource information, the resource for the sidelink communication may be selected from resources other than the first resource region indicated by the resource coordination information.

The step of selecting the resource for the sidelink communication includes performing a resource sensing operation, and overlapping between a first resource region indicated by the resource coordination information and a second resource region according to a result of the resource sensing operation. If the resource exists, selecting the overlapped resource for the sidelink communication in the first resource region or the second resource region.

In the step of selecting the resource for the sidelink communication, when the first resource region is different from the second resource region and the priority of the resource coordination information is higher than the priority of the result of the resource sensing operation, the The method may include preferentially selecting a resource for the sidelink communication within one resource region.

In the step of selecting the resource for the sidelink communication, when the first resource region is different from the second resource region and the priority of the resource coordination information is lower than the priority of the result of the resource sensing operation, the The method may include preferentially selecting a resource for the sidelink communication within two resource regions.

The method of operating the transmitting terminal may further include receiving a message including at least one of priority information of the resource coordination information and priority information of a result of the resource sensing operation.

The maximum number of resource regions indicated by the resource coordination information may be three or more.

The size of the subchannel indicated by the resource coordination information may be set to be different from the size of the subchannel through which the data is transmitted and received.

The resource pool indicated by the resource coordination information may be configured independently, and the resource coordination information may be received within the resource pool.

The resource coordination information may have a high priority so that the transmission resource of the resource coordination information is not preempted.

The method of operating the transmitting terminal may further include periodically receiving updated resource coordination information.

The method of operating the transmitting terminal may further include receiving updated resource adjustment information according to an event occurrence or an update request.

A transmitting terminal according to a second embodiment of the present invention for achieving the above object includes a processor, a memory in electronic communication with the processor, and instructions stored in the memory, wherein the instructions are executed by the processor In this case, the instructions indicate that the transmitting terminal receives resource coordination information, selects a resource for sidelink communication based on the resource coordination information, and transmits data to one or more receiving terminals using the selected resource. and the resource coordination information is one of preferred resource information and non-preferred resource information for the sidelink communication.

The instructions may be further operable to cause the transmitting terminal to receive an indicator indicating that the resource coordination information is the preferred resource information or the non-preferred resource information, wherein the resource coordination information is the preferred resource information When the resource for the sidelink communication is selected within the first resource region indicated by the resource coordination information, and the resource coordination information is the non-preferred resource information, the resource for the sidelink communication is the resource coordination information It may be selected from within resources other than the first resource area indicated by .

When selecting a resource for the sidelink communication, the instructions are that the transmitting terminal performs a resource sensing operation, and a first resource region indicated by the resource coordination information and a second resource region according to the result of the resource sensing operation. If there is an overlapping resource between two resource regions, the overlapping resource may be selected for the sidelink communication in the first resource region or the second resource region.

When selecting a resource for the sidelink communication, the instructions indicate to the transmitting terminal that the first resource region is different from the second resource region, and the priority of the resource coordination information is the priority of the result of the resource sensing operation. If it is higher than the priority, it may operate to preferentially select a resource for the sidelink communication within the first resource region.

When selecting a resource for the sidelink communication, the instructions indicate to the transmitting terminal that the first resource region is different from the second resource region, and the priority of the resource coordination information is the priority of the result of the resource sensing operation. If it is lower than the priority, it may operate to cause selection of the resource for the sidelink communication preferentially in the second resource region.

The maximum number of resource regions indicated by the resource adjustment information may be three or more, and the size of a subchannel indicated by the resource adjustment information may be set to be different from the size of a subchannel through which the data is transmitted and received.

According to embodiments, even when sidelink communication is performed based on mode 2, sidelink resources may be coordinated. That is, in order to prevent resource collision between terminals, sidelink resources may be adjusted. Sidelink communication may be performed based on coordinated resources, and thus resource collision between terminals may be reduced. That is, the performance of the communication system may be improved. In addition, since the resource sensing operation and/or the resource selection operation may be performed within limited resources (eg, coordinated resources), energy efficiency may be improved.

1 is a conceptual diagram illustrating a first embodiment of a communication system.
2 is a block diagram showing a first embodiment of a communication node constituting a communication system.
3 is a conceptual diagram illustrating a first embodiment of a type 1 frame structure.
4 is a conceptual diagram illustrating a first embodiment of a type 2 frame structure.
5 is a conceptual diagram illustrating a first embodiment of a method for transmitting an SS/PBCH block in a communication system.
6 is a conceptual diagram illustrating a first embodiment of an SS/PBCH block in a communication system.
7 is a conceptual diagram illustrating a second embodiment of a method for transmitting an SS/PBCH block in a communication system.
8A is a conceptual diagram illustrating an RMSI CORESET mapping pattern #1 in a communication system.
8B is a conceptual diagram illustrating RMSI CORESET mapping pattern #2 in a communication system.
8C is a conceptual diagram illustrating RMSI CORESET mapping pattern #3 in a communication system.
9 is a conceptual diagram illustrating embodiments of a method for multiplexing a control channel and a data channel in sidelink communication.
10 is a conceptual diagram illustrating a first embodiment of a method for setting a resource set(s).
11 is a conceptual diagram illustrating a first embodiment of a resource pattern for time and frequency resources.
12 is a conceptual diagram illustrating a first embodiment of resource pool setting for resource coordination.
13 is a conceptual diagram illustrating a first embodiment of a resource setting method for a triggering signal and/or a keeping signal.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

When an element is referred to as being “connected” or “connected” to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In describing the present invention, in order to facilitate the overall understanding, the same reference numerals are used for the same components in the drawings, and duplicate descriptions of the same components are omitted.

A communication system to which embodiments according to the present invention are applied will be described. The communication system to which the embodiments according to the present invention are applied is not limited to the content described below, and the embodiments according to the present invention can be applied to various communication systems. Here, a communication system may be used in the same sense as a communication network (network).

1 is a conceptual diagram illustrating a first embodiment of a communication system.

1, the communication system 100 is a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system 100 is a core network (core network) (eg, S-GW (serving-gateway), P-GW (packet data network (PDN)-gateway), MME (mobility management entity)) may include more. When the communication system 100 is a 5G communication system (eg, a new radio (NR) system), the core network is an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc. may include

The plurality of communication nodes 110 to 130 may support a communication protocol (eg, an LTE communication protocol, an LTE-A communication protocol, an NR communication protocol, etc.) defined in a 3rd generation partnership project (3GPP) standard. A plurality of communication nodes 110 to 130 are CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division) technology multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA Technology, Non-orthogonal Multiple Access (NOMA) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (Space Division Multiple Access) technology, etc. can support Each of the plurality of communication nodes may have the following structure.

2 is a block diagram showing a first embodiment of a communication node constituting a communication system.

Referring to FIG. 2 , the communication node 200 may include at least one processor 210 , a memory 220 , and a transceiver 230 connected to a network to perform communication. In addition, the communication node 200 may further include an input interface device 240 , an output interface device 250 , a storage device 260 , and the like. Each of the components included in the communication node 200 may be connected by a bus 270 to communicate with each other.

However, each of the components included in the communication node 200 may not be connected to the common bus 270 but to the processor 210 through an individual interface or an individual bus. For example, the processor 210 may be connected to at least one of the memory 220 , the transceiver 230 , the input interface device 240 , the output interface device 250 , and the storage device 260 through a dedicated interface. .

The processor 210 may execute a program command stored in at least one of the memory 220 and the storage device 260 . The processor 210 may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. Each of the memory 220 and the storage device 260 may be configured as at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may be configured as at least one of a read only memory (ROM) and a random access memory (RAM).

Referring back to FIG. 1 , the communication system 100 includes a plurality of base stations 110 - 1 , 110 - 2 , 110 - 3 , 120 - 1 and 120 - 2 , and a plurality of terminals 130 - 1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell. Each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the cell coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the cell coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong to the cell coverage of the third base station 110-3. have. The first terminal 130-1 may belong to the cell coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong to the cell coverage of the fifth base station 120-2.

Here, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a NodeB (NB), an evolved NodeB (eNB), gNB, an advanced base station (ABS), HR - BS (high reliability-base station), BTS (base transceiver station), radio base station (radio base station), radio transceiver (radio transceiver), access point (access point), access node (node), RAS (radio access station) ), MMR-BS (mobile multihop relay-base station), RS (relay station), ARS (advanced relay station), HR-RS (high reliability-relay station), HNB (home NodeB), HeNB (home eNodeB), It may be referred to as a road side unit (RSU), a radio remote head (RRH), a transmission point (TP), a transmission and reception point (TRP), and the like.

Each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 includes a user equipment (UE), a terminal equipment (TE), an advanced mobile station (AMS), HR-MS (high reliability-mobile station), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable It may be referred to as a portable subscriber station, a node, a device, an on board unit (OBU), and the like.

Meanwhile, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may operate in different frequency bands or may operate in the same frequency band. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to each other through an ideal backhaul link or a non-ideal backhaul link. , information can be exchanged with each other through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to the core network through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits a signal received from the core network to the corresponding terminals 130-1, 130-2, 130-3, 130 -4, 130-5, 130-6), and a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) is transmitted to the core network can be sent to

In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits MIMO (eg, single user (SU)-MIMO, multi user (MU)- MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, direct communication between terminals (device to device communication, D2D) (or , Proximity Services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), and the like may be supported. Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 is the base station 110-1, 110-2, 110-3, and 120-1. , 120-2) and corresponding operations, and operations supported by the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be performed. For example, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 based on the SU-MIMO method, and the fourth terminal 130-4 may transmit a signal based on the SU-MIMO method. A signal may be received from the second base station 110 - 2 . Alternatively, the second base station 110 - 2 may transmit a signal to the fourth terminal 130 - 4 and the fifth terminal 130 - 5 based on the MU-MIMO scheme, and the fourth terminal 130 - 4 . and each of the fifth terminals 130 - 5 may receive a signal from the second base station 110 - 2 by the MU-MIMO method.

Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may transmit a signal to the fourth terminal 130-4 based on the CoMP scheme, and the fourth The terminal 130-4 may receive signals from the first base station 110-1, the second base station 110-2, and the third base station 110-3 by the CoMP method. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a terminal 130-1, 130-2, 130-3, 130-4 belonging to its own cell coverage. , 130-5, 130-6) and the CA method can transmit and receive signals. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 controls D2D between the fourth terminal 130-4 and the fifth terminal 130-5. and each of the fourth terminal 130-4 and the fifth terminal 130-5 may perform D2D under the control of the second base station 110-2 and the third base station 110-3, respectively. .

Meanwhile, the communication system may support three types of frame structures. The type 1 frame structure may be applied to a frequency division duplex (FDD) communication system, the type 2 frame structure may be applied to a time division duplex (TDD) communication system, and the type 3 frame structure may be applied to an unlicensed band-based communication system (eg, For example, it may be applied to a licensed assisted access (LAA) communication system.

3 is a conceptual diagram illustrating a first embodiment of a type 1 frame structure.

Referring to FIG. 3 , a radio frame 300 may include 10 subframes, and the subframe may include two slots. Accordingly, the radio frame 300 may include 20 slots (eg, slot #0, slot #1, slot #2, slot #3, ..., slot #18, slot #19). The length of the radio frame 300 (T _f ) may be 10 ms (millisecond), the subframe length may be 1 ms, and the slot length (T _slot ) may be 0.5 ms. Here, T _s may indicate a sampling time, and may be 1/30,720,000s (second).

A slot may be composed of a plurality of OFDM symbols in the time domain and may be composed of a plurality of resource blocks (RBs) in the frequency domain. A resource block may be composed of a plurality of subcarriers in the frequency domain. The number of OFDM symbols constituting a slot may vary according to the configuration of a cyclic prefix (CP). The CP may be classified into a normal CP and an extended CP. When a normal CP is used, a slot may be composed of 7 OFDM symbols, and in this case, a subframe may be composed of 14 OFDM symbols. When the extended CP is used, a slot may be composed of 6 OFDM symbols, and in this case, a subframe may be composed of 12 OFDM symbols.

4 is a conceptual diagram illustrating a first embodiment of a type 2 frame structure.

Referring to FIG. 4 , a radio frame 400 may include two half frames, and a half frame may include five subframes. Accordingly, the radio frame 400 may include 10 subframes. The length of the radio frame 400 (T _f ) may be 10 ms. The length of the half frame may be 5 ms. The subframe length may be 1 ms. Here, T _s may be 1/30,720,000s.

The radio frame 400 may include a downlink subframe, an uplink subframe, and a special subframe. Each of the downlink subframe and the uplink subframe may include two slots. The slot length (T _slot ) may be 0.5 ms. Among the subframes included in the radio frame 400 , each of subframe #1 and subframe #6 may be a special subframe. For example, when the downlink-uplink switching period is 5 ms, the radio frame 400 may include two special subframes. Alternatively, when the downlink-uplink switching period is 10 ms, the radio frame 400 may include one special subframe. The special subframe may include a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS).

The downlink pilot time slot may be regarded as a downlink interval, and may be used for cell search of the terminal, time and frequency synchronization acquisition, channel estimation, and the like. The guard period may be used to solve an uplink data transmission interference problem caused by downlink data reception delay. In addition, the guard period may include a time required for switching from the downlink data reception operation to the uplink data transmission operation. The uplink pilot time slot may be used for uplink channel estimation, time and frequency synchronization acquisition, and the like. Transmission of a physical random access channel (PRACH) or a sounding reference signal (SRS) may be performed in an uplink pilot time slot.

Lengths of the downlink pilot time slot, guard period, and uplink pilot time slot included in the special subframe may be variably adjusted as necessary. In addition, the number and position of each of the downlink subframe, the uplink subframe, and the special subframe included in the radio frame 400 may be changed as needed.

In a communication system, a transmission time interval (TTI) may be a basic time unit for transmitting encoded data through a physical layer. A short TTI may be used to support low latency requirements in a communication system. The length of the short TTI may be less than 1 ms. The existing TTI having a length of 1 ms may be referred to as a base TTI or a regular TTI. That is, the basic TTI may consist of one subframe. In order to support transmission in a basic TTI unit, a signal and a channel may be configured in a subframe unit. For example, a cell-specific reference signal (CRS), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), etc. exist for each subframe. can

On the other hand, a synchronization signal (eg, a primary synchronization signal (PSS), a secondary synchronization signal (SSS)) may exist every 5 subframes, and a physical broadcast channel (PBCH) may exist every 10 subframes. And radio frames can be distinguished by SFN, and SFN is a signal having a transmission period longer than one radio frame (eg, a paging signal, a reference signal for channel estimation, a signal indicating channel state information, etc.) can be used to define the transport of The period of the SFN may be 1024.

In the LTE system, the PBCH may be a physical layer channel used for transmission of system information (eg, a master information block (MIB)). The PBCH may be transmitted every 10 subframes. That is, the transmission period of the PBCH may be 10 ms, and the PBCH may be transmitted once in a radio frame. The same MIB may be transmitted during 4 consecutive radio frames, and after 4 consecutive radio frames, the MIB may be changed according to the situation of the LTE system. The transmission period of the same MIB may be referred to as "PBCH TTI", and the PBCH TTI may be 40 ms. That is, the MIB may be changed for each PBCH TTI.

The MIB may be composed of 40 bits. Of the 40 bits constituting the MIB, 3 bits may be used to indicate a system band, 3 bits may be used to indicate PHICH (physical hybrid automatic repeat request (ARQ) indicator channel) related information, and 8 bits are It may be used to indicate the SFN, 10 bits may be set as a reserved bit, and 16 bits may be used for a cyclic redundancy check (CRC).

The SFN that distinguishes the radio frame may consist of a total of 10 bits (B9 to B0), and among the 10 bits, 8 bits (B9 to B2) of the most significant bit (MSB) may be indicated by the PBCH (ie, MIB). . The MSB 8 bits (B9 to B2) of the SFN indicated by the PBCH (ie, MIB) may be the same during four consecutive radio frames (ie, PBCH TTI). The least significant bit (LSB) 2 bits (B1 to B0) of the SFN may be changed during 4 consecutive radio frames (ie, PBCH TTI), and may not be explicitly indicated by the PBCH (ie, MIB) have. The LSB 2 bits (B1 to B0) of the SFN may be implicitly indicated by a scrambling sequence for the PBCH (hereinafter, referred to as a “PBCH scrambling sequence”).

A gold sequence generated by being initialized with a cell ID may be used as the PBCH scrambling sequence, and the PBCH scrambling sequence may be initialized every four consecutive radio frames (ie, PBCH TTI) according to mod(SFN,4). have. A PBCH transmitted in a radio frame corresponding to an SFN in which LSB 2 bits (B1 to B0) is set to “00” may be scrambled by a Gold sequence generated by being initialized with a cell ID. Thereafter, the gold sequences generated according to mod(SFN,4) are used for scrambling the PBCH transmitted in the radio frame in which the LSB 2 bits (B1 to B0) of the SFN are “01”, “10” and “11”. can

Therefore, the UE, which has obtained the cell ID in the initial cell search process, uses the PBCH scrambling sequence in the decoding process of the PBCH (ie, the MIB) to the value of the LSB 2 bits (B1 to B0) of the SFN (e.g., "00", " 01", "10", "11") can be found implicitly. The UE uses the LSB 2 bits (B1 to B0) of the SFN identified based on the PBCH scrambling sequence and the MSB 8 bits (B9 to B2) of the SFN indicated by the PBCH (ie, MIB) to the SFN (ie, the SFN All bits (B9~B0)) can be checked.

Meanwhile, the communication system may support not only high transmission speed but also technical requirements for various service scenarios. For example, the communication system may support a high transmission rate (enhanced Mobile BroadBand; eMBB), a short transmission delay time (Ultra Reliable Low Latency Communication; URLLC), and massive machine type communication (mMTC).

A subcarrier interval of a communication system (eg, an OFDM-based communication system) may be determined based on a carrier frequency offset (CFO) or the like. The CFO may be caused by a Doppler effect, a phase drift, or the like, and may increase in proportion to an operating frequency. Accordingly, in order to prevent degradation of the communication system due to the CFO, the subcarrier spacing may increase in proportion to the operating frequency. On the other hand, as the subcarrier spacing increases, CP overhead may increase. Accordingly, the subcarrier interval may be set based on channel characteristics according to frequency bands, radio frequency (RF) characteristics, and the like.

The communication system may support numerology defined in Table 1 below.

For example, the subcarrier spacing of the communication system may be set to 15 kHz, 30 kHz, 60 kHz, or 120 kHz. The subcarrier spacing of the LTE system may be 15 kHz, and the subcarrier spacing in the NR system may be 1, 2, 4 or 8 times the existing subcarrier spacing of 15 kHz. When the subcarrier spacing is increased by an exponential multiple of 2 of the existing subcarrier spacing, the frame structure can be easily designed.

The communication system may support a wide frequency band (eg, several hundred MHz to several tens of GHz). Since the diffraction and reflection characteristics of radio waves in the high frequency band are poor, propagation loss (eg, path loss, return loss, etc.) in the high frequency band may be larger than the propagation loss in the low frequency band. Accordingly, the cell coverage of the communication system supporting the high frequency band may be smaller than the cell coverage of the communication system supporting the low frequency band. In order to solve this problem, a beamforming method based on a plurality of antenna elements may be used to increase cell coverage in a communication system supporting a high frequency band.

The beamforming method may include a digital beamforming method, an analog beamforming method, a hybrid beamforming method, and the like. In a communication system using a digital beamforming method, a beamforming gain may be obtained using a plurality of RF paths based on a digital precoder or a codebook. In a communication system using an analog beamforming method, a beamforming gain may be obtained through an analog RF device (eg, a phase shifter, a power amplifier (PA), a variable gain amplifier (VGA), etc.) and an antenna array. can

Since expensive digital to analog converter (DAC) or analog to digital converter (ADC) and transceiver units corresponding to the number of antenna elements are required for the digital beamforming method, an antenna for increasing the beamforming gain Implementation complexity may be increased. Since a plurality of antenna elements are connected to one transceiver unit through a phase shifter in a communication system using an analog beamforming method, even when a beamforming gain is increased, the complexity of antenna implementation may not significantly increase. However, the beamforming performance of the communication system using the analog beamforming method may be lower than the beamforming performance of the communication system using the digital beamforming method. In addition, since the phase shifter is adjusted in the time domain in a communication system using the analog beamforming method, frequency resources may not be efficiently used. Therefore, a hybrid beamforming method that is a combination of a digital method and an analog method may be used.

When cell coverage is increased by using the beamforming method, a common control channel and a common signal (eg, a reference signal, a synchronization signal) for all terminals belonging to the cell coverage as well as a control channel and data channel of each terminal may also be transmitted based on a beamforming method. In this case, a common control channel and a common signal for all terminals belonging to cell coverage may be transmitted based on a beam sweeping scheme.

Also, in the NR system, a synchronization block/physical broadcast channel (SS/PBCH) block may be transmitted in a beam sweeping scheme. The SS/PBCH block may be configured with PSS, SSS, PBCH, and the like, and the PSS, SSS, and PBCH within the SS/PBCH block may be configured with a time division multiplexing (TDM) scheme. The SS/PBCH block may be referred to as an “SS/PBCH block”. One SS/PBCH block may be transmitted using N consecutive OFDM symbols. Here, N may be an integer of 4 or more. The base station may periodically transmit the SS/PBCH block, and the terminal may acquire frequency/time synchronization, cell ID, system information, and the like, based on the SS/PBCH block received from the base station. The SS/PBCH block may be transmitted as follows.

5 is a conceptual diagram illustrating a first embodiment of a method for transmitting an SS/PBCH block in a communication system.

Referring to FIG. 5 , one or more SS/PBCH blocks in an SS/PBCH block burst set may be transmitted in a beam sweeping scheme. A maximum of L SS/PBCH blocks may be transmitted in one SS/PBCH block burst set. L may be an integer of 2 or more, and may be defined in the 3GPP standard. L may vary according to the region of the system frequency. In the SS/PBCH block burst set, SS/PBCH blocks may be located contiguously or distributedly. Contiguous SS/PBCH blocks may be referred to as “SS/PBCH block bursts”. The SS/PBCH block burst set may be periodically repeated, and system information (eg, MIB) transmitted through the PBCH of SS/PBCH blocks within the SS/PBCH block burst set may be the same. SS/PBCH block index, SS/PBCH block burst index, OFDM symbol index, slot index, etc. may be explicitly or implicitly indicated by the PBCH.

6 is a conceptual diagram illustrating a first embodiment of an SS/PBCH block in a communication system.

Referring to FIG. 6 , the arrangement order in the SS/PBCH block may be “PSS → PBCH → SSS → PBCH”. In the SS/PBCH block, PSS, SSS, and PBCH may be configured in a TDM manner. In the symbol in which the SSS is located, the PBCH may be disposed in frequency resources higher than the SSS and frequency resources lower than the SSS. When the maximum number of SS/PBCH blocks is 8 in a frequency band of 6 GHz or less, the index of the SS/PBCH block is based on a demodulation reference signal (DMRS) used for demodulation of the PBCH (hereinafter referred to as "PBCH DMRS"). can be confirmed as When the maximum number of SS/PBCH blocks is 64 in a frequency band of 6 GHz or higher, 3 LSB bits among 6 bits indicating the index of the SS/PBCH block may be identified based on the PBCH DMRS, and the remaining 3 MSB bits are the PBCH pay It can be identified based on the load.

The maximum system bandwidth supportable in the NR system may be 400 MHz. The size of the maximum bandwidth supportable by the terminal may vary according to the capability of the terminal. Accordingly, the UE may perform an initial access procedure (eg, an initial connection procedure) using some of the system bandwidths of the NR system supporting broadband. In order to support the access procedure of terminals supporting various sizes of bandwidth, the SS/PBCH block may be multiplexed on the frequency axis within the system bandwidth of the NR system supporting wideband. In this case, the SS/PBCH block may be transmitted as follows.

7 is a conceptual diagram illustrating a second embodiment of a method for transmitting an SS/PBCH block in a communication system.

Referring to FIG. 7 , a broadband component carrier (CC) may include a plurality of bandwidth parts (BWP). For example, a wideband CC may include 4 BWPs. The base station may transmit the SS/PBCH block in each of BWP #0 to 3 belonging to the broadband CC. The UE may receive an SS/PBCH block in one or more BWPs of BWP #0 to 3, and may perform an initial access procedure using the received SS/PBCH block.

After detecting the SS/PBCH block, the UE may acquire system information (eg, remaining minimum system information (RMSI)) and may perform a cell access procedure based on the system information. The RMSI may be transmitted through the PDSCH scheduled by the PDCCH. Configuration information of a control resource set (CORESET) in which a PDCCH including scheduling information of a PDSCH in which RMSI is transmitted is transmitted may be transmitted through a PBCH in an SS/PBCH block. A plurality of SS/PBCH blocks may be transmitted in the entire system band, and one or more SS/PBCH blocks among the plurality of SS/PBCH blocks may be an SS/PBCH block associated with an RMSI. The remaining SS/PBCH blocks may not be associated with RMSI. The SS/PBCH block associated with the RMSI may be defined as a "cell defining SS/PBCH block". The UE may perform a cell search procedure and an initial access procedure using a cell-defined SS/PBCH block. The SS/PBCH block not associated with the RMSI may be used for a synchronization procedure and/or a measurement procedure in the corresponding BWP. The BWP through which the SS/PBCH block is transmitted may be limited to one or more BWPs within a wide bandwidth.

RMSI is "Acquiring CORESET configuration information from SS/PBCH block (eg, PBCH) → PDCCH detection based on CORESET configuration information → PDSCH scheduling information acquisition from PDCCH → RMSI through PDSCH may be obtained by performing an "operation of receiving The transmission resource of the PDCCH may be configured by CORESET configuration information. The RMSI CORESET mapping pattern may be defined as follows. The RMSI CORESET may be a CORESET used for RMSI transmission/reception.

8A is a conceptual diagram illustrating RMSI CORESET mapping pattern #1 in a communication system, FIG. 8B is a conceptual diagram illustrating RMSI CORESET mapping pattern #2 in a communication system, and FIG. 8C illustrates RMSI CORESET mapping pattern #3 in a communication system It is a conceptual diagram.

8A to 8C , one RMSI CORESET mapping pattern among RMSI CORESET mapping patterns #1-3 may be used, and detailed setting according to one RMSI CORESET mapping pattern may be completed. In the RMSI CORESET mapping pattern #1, the SS/PBCH block, CORESET (eg, RMSI CORESET), and PDSCH (eg, RMSI PDSCH) may be configured in a TDM manner. The RMSI PDSCH may mean a PDSCH through which RMSI is transmitted. In RMSI CORESET mapping pattern #2, CORESET (eg, RMSI CORESET) and PDSCH (eg, RMSI PDSCH) may be configured in a TDM manner, and PDSCH (eg, RMSI PDSCH) is an SS/PBCH block and frequency division multiplexing (FDM). In RMSI CORESET mapping pattern #3, CORESET (eg, RMSI CORESET) and PDSCH (eg, RMSI PDSCH) may be set in a TDM manner, and CORESET (eg, RMSI CORESET) and PDSCH (eg, RMSI CORESET) For example, RMSI PDSCH) may be configured in an SS/PBCH block and FDM scheme.

Only RMSI CORESET mapping pattern #1 can be used in a frequency band of 6 GHz or less. All of the RMSI CORESET mapping patterns #1, #2, and #3 may be used in the frequency band above 6 GHz. The numerology of the SS/PBCH block may be different from that of "RMSI CORESET and RMSI PDSCH". Here, the neuronology may be a subcarrier spacing. In the RMSI CORESET mapping pattern #1, a combination of all neumonologies can be used. In RMSI CORESET mapping pattern #2, a combination of "SS/PBCH block, RMSI CORESET/PDSCH = 120 kHz, 60 kHz or 240 kHz, 120 kHz" may be used. In RMSI CORESET mapping pattern #3, a combination of "SS/PBCH block, RMSI CORESET/PDSCH = 120 kHz, 120 kHz" may be used.

One RMSI CORESET mapping pattern may be selected from among RMSI CORESET mapping patterns #1-3 according to a combination of the neumonology of the SS/PBCH block and the neumonology of the RMSI CORESET/PDSCH. The setting information of RMSI CORESET may include table A and table B. Table A shows the number of resource blocks (RBs) of RMSI CORESET, the number of symbols of RMSI CORESET, and RBs of SS/PBCH blocks (eg, start RBs or end RBs) and RBs of RMSI CORESETs (eg, start RBs). Alternatively, it may indicate an offset between the end RBs). Table B may indicate the number of search space sets per slot in each of the RMSI CORESET mapping patterns, the offset of the RMSI CORESET, and the OFDM symbol index. Table B may indicate information for setting a monitoring occasion of the RMSI PDCCH. Each of the tables A and B may include a plurality of tables. For example, Table A may include Tables 13-1 to 13-8 specified in TS 38.213, and Table B may include Tables 13-9 to Table 13-13 specified in TS 38.213. Each of Table A and Table B may have a size of 4 bits.

In the NR system, the PDSCH may be mapped to the time domain according to PDSCH mapping type A or B. PDSCH mapping types A and B may be defined as shown in Table 2 below.

Type A (ie, PDSCH mapping type A) may be slot-based transmission. When type A is used, the position of the start symbol of the PDSCH may be set to one of {0, 1, 2, 3}. When type A and normal CP are used, the number of symbols constituting the PDSCH (eg, the duration of the PDSCH) may be set to one of 3 to 14 within a symbol boundary. Type B (ie, PDSCH mapping type B) may be non-slot-based transmission. When type B is used, the position of the start symbol of the PDSCH may be set to one of 0 to 12. When type B and normal CP are used, the number of symbols constituting the PDSCH (eg, the duration of the PDSCH) may be set to one of {2, 4, 7} within a symbol boundary. The DMRS (hereinafter, referred to as "PDSCH DMRS") for demodulation of the PDSCH (eg, data) may be determined based on the PDSCH mapping type (eg, type A or type B) and ID indicating the length. The ID may be defined differently according to the PDSCH mapping type.

Meanwhile, NR-U (unlicensed) is being discussed at the NR standardization meeting. The NR-U system can increase network capacity by improving the utilization of limited frequency resources. The NR-U system may support operation in an unlicensed band (eg, unlicensed spectrum).

In the NR-U system, the UE may determine whether a signal is transmitted from the corresponding base station based on a discovery reference signal (DRS) received from the base station in the same way as in the general NR system. In the NR-U system of the SA (Stand-Alone) mode, the UE may acquire synchronization and/or system information based on the DRS. In the NR-U system, DRS may be transmitted according to the regulation of the unlicensed band (eg, transmission band, transmission power, transmission time, etc.). For example, according to an Occupied Channel Bandwidth (OCB) regulation, a signal may be configured and/or transmitted to occupy 80% of a total channel bandwidth (eg, 20 MHz).

In the NR-U system, a communication node (eg, a base station, a terminal) may perform a Listen Before Talk (LBT) before transmitting a signal and/or a channel for coexistence with other systems. The signal may be a synchronization signal or a reference signal (eg, DRS, DMRS, channel state information (CSI)-RS, phase tracking (PT)-RS, sounding reference signal (SRS)). The channel may be a downlink channel, an uplink channel, a sidelink channel, or the like. In embodiments, signal may mean “signal”, “channel”, or “signal and channel”. LBT may be an operation to check whether a signal is transmitted by another communication node. If it is determined by the LBT that there is no transmission signal (eg, when the LBT is successful), the communication node may transmit a signal in the unlicensed band. If it is determined by the LBT that the transmission signal exists (eg, when the LBT fails), the communication node may not be able to transmit a signal in the unlicensed band. The communication node may perform LBT according to various categories before transmission of a signal. The category of LBT may vary according to the type of transmission signal.

Meanwhile, NR V2X (vehicular to everything) communication technology is being discussed at the NR standardization conference. The NR V2X communication technology may be a technology that supports communication between vehicles, communication between vehicles and infrastructure, communication between vehicles and pedestrians, etc. based on a device to device (D2D) communication technology.

NR V2X communication (eg, sidelink communication) is to be performed according to three transmission schemes (eg, unicast scheme, broadcast scheme, groupcast scheme) can When the unicast method is used, a PC5-RRC connection may be established between the first terminal (eg, a transmitting terminal that transmits data) and a second terminal (eg, a receiving terminal that receives data), The PC5-RRC connection may mean a logical connection for a pair between the source ID of the first terminal and the destination ID of the second terminal. The first terminal may transmit data (eg, sidelink data) to the second terminal. When the broadcast method is used, the first terminal may transmit data to all terminals. When the groupcast method is used, the first terminal may transmit data to a group (eg, a groupcast group) including a plurality of terminals.

When the unicast method is used, the second terminal may transmit feedback information (eg, acknowledgment (ACK) or negative ACK (NACK)) on data received from the first terminal to the first terminal. In the embodiments below, the feedback information may be referred to as “HARQ-ACK”, “feedback signal”, “physical sidelink feedback channel (PSFCH) signal”, or the like. When the ACK is received from the second terminal, the first terminal may determine that data has been successfully received from the second terminal. When the NACK is received from the second terminal, the first terminal may determine that the second terminal has failed to receive data. In this case, the first terminal may transmit additional information to the second terminal based on a hybrid automatic repeat request (HARQ) method. Alternatively, the first terminal may improve the reception probability of data in the second terminal by retransmitting the same data to the second terminal.

When the broadcast method is used, a procedure for transmitting feedback information for data may not be performed. For example, the system information may be transmitted in a broadcast manner, and the terminal may not transmit feedback information on the system information to the base station. Accordingly, the base station may not know whether the system information has been successfully received from the terminal. To solve this problem, the base station may periodically broadcast system information.

When the groupcast method is used, a procedure for transmitting feedback information for data may not be performed. For example, necessary information may be periodically transmitted in a groupcast method without a procedure for transmitting feedback information. However, the target and/or number of terminals participating in the communication based on the groupcast method is limited, and data transmitted in the groupcast method is data that must be received within a preset time (eg, data sensitive to delay). In this case, a procedure for transmitting feedback information may be required even in groupcast sidelink communication. The groupcast sidelink communication may refer to sidelink communication performed in a groupcast method. When the feedback information transmission procedure is performed in groupcast sidelink communication, data can be transmitted and received efficiently and stably.

In groupcast sidelink communication, two HARQ-ACK feedback schemes (ie, feedback information transmission procedure) may be supported. When "the number of receiving terminals in the sidelink group is large and service scenario 1 is supported", some receiving terminals belonging to a specific range in the sidelink group may transmit a NACK through the PSFCH when data reception fails. This scheme may be “groupcast HARQ-ACK feedback option 1”. In service scenario 1, instead of all the receiving terminals in the sidelink group, it may be allowed for some receiving terminals belonging to a specific range to receive in the best-effort manner. Service scenario 1 may be an extended sensor scenario in which some receiving terminals belonging to a specific range need to receive the same sensor information from a transmitting terminal. In embodiments, the transmitting terminal may mean a terminal transmitting data, and the receiving terminal may mean a terminal receiving data.

If "the number of receiving terminals in the sidelink group is limited and service scenario 2 is supported", each of all receiving terminals belonging to the sidelink group may individually report HARQ-ACK for data through a separate PSFCH. have. This scheme may be “groupcast HARQ-ACK feedback option 2”. In service scenario 2, since the PSFCH resource is sufficient, the transmitting terminal can monitor the HARQ-ACK feedback of all receiving terminals belonging to the sidelink group, and data reception is guaranteed by all the receiving terminals belonging to the sidelink group can be

In addition, data reliability in the receiving terminal may be improved by appropriately adjusting the power of the transmitting terminal according to the transmission environment. Interference to other terminals can be mitigated by appropriately adjusting the power of the transmitting terminal. Energy efficiency can be improved by reducing unnecessary transmit power. The power control method may be classified into an open-loop power control method and a closed-loop power control method. In the open-loop power control method, the transmitting terminal may determine the transmit power in consideration of a set and measured environment, and the like. In the closed-loop power control scheme, the transmitting terminal may determine the transmit power based on a transmit power control (TPC) command received from the receiving terminal.

Predicting the received signal strength in the receiving terminal may be difficult due to various causes including a multipath fading channel, interference, and the like. Accordingly, the reception terminal may adjust the reception power level (eg, reception power range) by performing an automatic gain control (AGC) operation in order to prevent a quantization error of the reception signal and maintain appropriate reception power. In a communication system, a terminal may perform an AGC operation using a reference signal received from a base station. However, in sidelink communication (eg, V2X communication), the reference signal may not be transmitted from the base station. That is, in sidelink communication, communication between terminals may be performed without a base station. Therefore, it may be difficult to perform an AGC operation in sidelink communication. In sidelink communication, the transmitting terminal may first transmit a signal (eg, a reference signal) to the receiving terminal before transmission of data, and the receiving terminal performs an AGC operation based on the signal received from the transmitting terminal, thereby receiving power range (eg, a received power level) may be adjusted. Thereafter, the transmitting terminal may transmit the sidelink data to the receiving terminal. The signal used for the AGC operation may be a duplicated signal for a signal to be transmitted later or a signal preset between terminals.

The time period required for the AGC operation may be 15 μs. When the subcarrier interval is 15 kHz in the NR system, the time interval (eg, length) of one symbol (eg, OFDM symbol) may be 66.7 μs. When the subcarrier interval is 30 kHz in the NR system, the time interval of one symbol (eg, OFDM symbol) may be 33.3 μs. In the embodiments below, a symbol may mean an OFDM symbol. That is, the time interval of one symbol may be twice or more than the time interval required for the AGC operation.

For sidelink communication, it may be necessary to transmit a data channel for data transmission and a control channel including scheduling information for data resource allocation. In sidelink communication, the data channel may be a Physical Sidelink Shared CHannel (PSSCH), and the control channel may be a Physical Sidelink Control CHannel (PSCCH). The data channel and the control channel may be multiplexed in a resource domain (eg, a time and frequency resource domain).

9 is a conceptual diagram illustrating embodiments of a method for multiplexing a control channel and a data channel in sidelink communication.

Referring to FIG. 9 , sidelink communication may support option 1A, option 1B, option 2, and option 3. If option 1A and/or option 1B is supported, the control channel and data channel may be multiplexed in the time domain. If option 2 is supported, the control channel and data channel can be multiplexed in the frequency domain. If option 3 is supported, the control channel and data channel can be multiplexed in time and frequency domains. Sidelink communication can support option 3 natively.

In sidelink communication (eg, NR-V2X sidelink communication), a basic unit of resource configuration may be a subchannel. A subchannel may be defined by time and frequency resources. For example, a subchannel may be composed of a plurality of symbols (eg, OFDM symbols) in the time domain and may be composed of a plurality of resource blocks (RBs) in the frequency domain. A subchannel may be referred to as an RB set. In the subchannel, the data channel and the control channel can be multiplexed based on option 3.

In sidelink communication (eg, NR-V2X sidelink communication), transmission resources may be allocated based on mode 1 or mode 2. When mode 1 is used, the base station may allocate a sidelink resource for data transmission to the transmitting terminal in a resource pool, and the transmitting terminal receives data using the sidelink resource allocated by the base station. It can be transmitted to the terminal. Here, the transmitting terminal may be a terminal transmitting data in sidelink communication, and the receiving terminal may be a terminal receiving data in sidelink communication.

When mode 2 is used, the transmitting terminal may autonomously select a sidelink resource to be used for data transmission by performing a resource sensing operation and/or a resource selection operation within the resource pool. The base station may set a resource pool for mode 1 and a resource pool for mode 2 in the terminal(s). The resource pool for mode 1 may be set independently of the resource pool for mode 2. Alternatively, a common resource pool may be configured for mode 1 and mode 2.

Next, methods for coordination and allocation of one or more sidelink resources in a communication system will be described. Even when a method (eg, transmission or reception of a signal) performed in a first communication node among communication nodes is described, a corresponding second communication node is a method (eg, a method corresponding to the method performed in the first communication node) For example, reception or transmission of a signal) may be performed. That is, when the operation of the transmitting terminal is described, the corresponding receiving terminal may perform an operation corresponding to the operation of the transmitting terminal. Conversely, when the operation of the receiving terminal is described, the corresponding transmitting terminal may perform an operation corresponding to the operation of the receiving terminal.

When mode 1 is used, the base station may schedule a resource used for sidelink data transmission to the transmitting terminal, and the transmitting terminal may transmit sidelink data to the receiving terminal using the resource scheduled by the base station. Therefore, resource collision between terminals can be prevented. When mode 2 is used, the transmitting terminal may select an arbitrary resource by performing a resource sensing operation and/or a resource selection operation, and may transmit sidelink data using the selected arbitrary resource. Since the above-described procedure is performed based on an individual resource sensing operation and/or resource selection operation of each transmitting terminal, a collision between selected resources may occur. Therefore, even when mode 2 is used, as in mode 1, a coordination operation of resources for data transmission and reception between terminals, a setting operation of a terminal performing the coordination operation, and a setting operation of a terminal notifying a resource according to the coordination operation , data transmission/reception operations between terminals using the coordinated resources may be performed. When the above-described operations are performed, collisions between resources may be reduced, and communication performance may be improved. When a resource sensing operation and/or a resource selection operation are performed within limited resources (eg, coordinated resources), energy efficiency may be improved.

When mode 2 is used, a terminal in charge of resource coordination and/or allocation for data transmission/reception between terminals may be selected. When resource coordination and/or allocation is performed by the selected terminal, collision between resources in sidelink communication may be reduced. Various scenarios that may support the above-described operations may exist. In groupcast communication (ie, groupcast sidelink communication), "communication between member terminals belonging to the groupcast group" and/or "communication between member terminals belonging to the groupcast group and terminals not belonging to the groupcast group" are performed can be In groupcast communication, a transmitting terminal (hereinafter referred to as a "groupcast (GC) transmitting terminal") is a "communication between member terminals belonging to a groupcast group" and/or "a member terminal belonging to a groupcast group and a member terminal belonging to a groupcast group. Resource adjustment and/or allocation operation may be performed for "communication between terminals that do not The GC transmission terminal may be referred to as a coordination terminal.

In embodiments, methods in which a GC transmitting terminal periodically transmits resource information suitable for communication to member terminals in a groupcast group will be proposed. The GC transmitting terminal receives not only sidelink data for its own groupcast communication, but also "communication between member terminals belonging to the groupcast group" and/or "communication between member terminals belonging to the groupcast group and terminals not belonging to the groupcast group" It is possible to transmit available resource information for Specifically, the GC transmitting terminal may recognize all member terminals in the groupcast group. In this case, the GC transmitting terminal may individually set the usable resource area according to the member ID of each of the member terminals in the groupcast group, and may transmit the configured resource information. The member ID may be a unique ID for identifying a member terminal within a groupcast group.

When the resource region includes a plurality of resource sets, the GC transmitting terminal may set one or more resource sets to each of the member terminals in the groupcast group, and transmit resource information related to the one or more resource sets. can Each of the member terminals in the sidelink group may receive resource information from the GC transmitting terminal, and perform "resource sensing and/or selection operation" or "random selection operation" within the resource set(s) indicated by the resource information. By performing it, some resource (eg, a resource set) may be selected, and sidelink communication may be performed using the selected resource. In embodiments, the resource sensing and/or selection operation may mean "resource sensing operation", "resource selection operation", or "resource sensing operation and resource selection operation".

10 is a conceptual diagram illustrating a first embodiment of a method for setting resource set(s).

Referring to FIG. 10 , the resource pool for mode 2 may be set independently of the resource pool for mode 1. When mode 2 is used, a resource region (eg, a resource pool) for transmission and reception of sidelink data may be divided into a plurality of resource sets, and one or more resource sets are member terminals within a sidelink group (eg, For example, it may be assigned to one member terminal). The resource set(s) configured for the member terminal may be linked (or mapped) to the member ID of the member terminal. That is, a mapping relationship (eg, association relationship) between the resource set index(s) and the member ID may be established. The resource set(s) of the member terminals may be signaled based on a mapping relationship between the resource set index(s) and the member ID.

Specifically, the GC transmitting terminal may transmit a combination of {member ID, resource set index}. When it is possible to allocate a plurality of resource sets to one member terminal, it may be signaled in the form of a combination of {member ID, resource set index #A, resource set index #B, resource set index #C}. A signaling operation for a plurality of member terminals may be performed in a combined form in the order of member IDs. The GC transmitting terminal may transmit configuration information of a resource set for a plurality of member terminals using a groupcast method. The resource set configuration information may be included in 1st sidelink control information (SCI), 2nd SCI, and/or sidelink data.

The maximum number of allocable resource sets may be preset. When a resource set equal to the maximum number of allocable resource sets is not set, a field corresponding to an unset resource set (eg, unassigned resource set) is a specific value (eg, a specific resource set index, All 0 (all zero), or all 1 (all one)) may be set. For example, "when the maximum number of allocable resource sets is 3 and two resource sets (eg, resource sets #A and #B) are set", the GC transmitting terminal is {member ID, resource set index #A, resource set index #B, all 1} may be set, and configured information (eg, {member ID, resource set index #A, resource set index #B, all 1}) may be signaled.

Alternatively, when member IDs are sequentially set, member IDs mapped to resource set indexes may not be signaled. In this case, the GC transmitting terminal may inform the member terminal(s) of configuration information of the resource set(s) without a member ID through signaling. The member terminal(s) may receive configuration information from the GC transmission terminal, and check the resource set(s) for itself in consideration of the order of member IDs among the resource set(s) indicated by the configuration information You can choose.

Some resources within the allocated resource set(s) may be used for actual data transmission. In this case, the member terminal(s) in the sidelink group may select a resource (eg, a resource region) by performing a “resource sensing and/or selection operation” or a “random selection operation” within the resource set(s). and can perform sidelink communication using the selected resource. An operation performed for resource selection within a resource set (eg, "resource sensing and/or selection operation" or "random selection operation") may be configured by system information and/or an RRC message. System information and/or RRC messages may be transmitted from the base station. The GC transmitting terminal may inform the member terminal(s) of an operation performed for resource selection in the resource set. In this case, the operation performed for resource selection in the resource set may be configured by the GC transmitting terminal. The GC transmitting terminal may inform an operation performed for resource selection in a resource set together with resource information (eg, resource allocation information).

One or more resource sets in a sidelink group may be allocated to a member terminal. In this case, the member terminal may perform sidelink communication with another member terminal belonging to a sidelink group or another terminal other than the sidelink group by using the resource(s) belonging to one or more resource sets. When communication is performed between member terminals belonging to a sidelink group, resource sets allocated to the member terminals may be shared, and sidelink communication between the member terminals may be performed using the shared resource sets. For example, in the embodiment shown in FIG. 10 , terminal A and terminal C may be member terminals belonging to a sidelink group. For sidelink communication between terminal A and terminal C, resource sets #0 and #1 allocated to terminal A and resource set #3 allocated to terminal C may be shared with each other. UE A and UE C may select resource(s) by performing “resource sensing and/or selection operation” or “random selection operation” in all of resource sets #0, #1, and #3, UE A and UE Sidelink communication between Cs may be performed using the selected resource(s).

Terminal A and terminal C may perform a monitoring operation for data reception in all of resource sets #0, #1, and #3. According to the above-described method, sidelink resources can be efficiently used. For example, when "resource set #3 is allocated to terminal C and more resources than resource set #3 are required for data transmission of terminal C", data transmission delay may occur in terminal C. However, when UE C shares resources with UE A, UE C may use resource sets #0, #1, and #3 for data transmission. Therefore, the terminal C can transmit data without a transmission delay.

"When data (eg, sidelink data) can be transmitted through successive subchannels in the frequency domain and resources required for data transmission are small", each of UE A and UE C is “resource set #3” Alternatively, a suitable resource may be selected by performing a “resource sensing and/or selection operation” or a “random selection operation” in “resource sets #0 and #1”, and sidelink communication may be performed using the selected suitable resource. . Suitable resources may be referred to as “recommended resources” or “preferred resources”. "When data can be transmitted through successive subchannels in the frequency domain and there are many resources required for data transmission", each of UE A and UE C has "resource sets #0 and #" instead of "resource set #3" 1", an appropriate resource may be selected by performing a "resource sensing and/or selection operation" or a "random selection operation", and sidelink communication may be performed using the selected suitable resource. When data transmission is possible through non-consecutive subchannels in the frequency domain, each of UE A and UE C performs “resource sensing and/or selection operation” or “random selection” in “resource sets #0, #1, and #3” By performing "operation", a suitable resource may be selected, and sidelink communication may be performed using the selected suitable resource.

Alternatively, in sidelink communication between member terminals in a sidelink group, each member terminal may transmit data only within a resource set allocated to it. For example, in the embodiment shown in FIG. 10, when sidelink communication between terminal A, which is a member terminal, and terminal C, is performed in a sidelink group, terminal A uses resource sets #0 and #1 allocated thereto. may be used to transmit data, and UE C may transmit data using resource set #3 allocated to itself. Terminal A may perform monitoring for data reception in resource sets #3 allocated to terminal C, and terminal C may perform monitoring for data reception in resource sets #0 and #1 allocated to terminal A . When a terminal (eg, a member terminal) performs a "resource sensing and/or selection operation" for data transmission based on the above-described method, the size of a resource region in which the "resource sensing and/or selection operation" is performed may be limited. In addition, the size of a resource region in which a monitoring operation for data reception is performed may be limited. In this case, the complexity of the terminal may be reduced, and energy efficiency may be increased.

In sidelink communication between member terminals in a sidelink group, a member terminal checks its own member ID and/or member ID of a counterpart member terminal by a procedure of establishing a PC5-RRC connection and/or a signaling procedure by a GC transmitting terminal. can The member terminal may check resource information (eg, resource set information) associated with the member ID based on the resource allocation information obtained from the GC transmitting terminal.

In the embodiment shown in FIG. 10 , a plurality of resource sets may be configured not to overlap each other in the time-frequency domain within the resource pool. Alternatively, in order to improve resource efficiency, a plurality of resource sets may be set to overlap in a time-frequency domain. In the embodiment shown in FIG. 10, the same time resource may be allocated to all terminals. It may be possible to allocate different time resources to the member terminals so that a half-duplex issue in which data transmission/reception time points overlap between member terminals does not occur.

The GC transmitting terminal may periodically transmit resource allocation information (eg, configuration information of a plurality of resource sets) to member terminals in the sidelink group. Alternatively, the resource allocation information may be transmitted when the previously allocated resource set is changed. In this case, the resource allocation information may include only changed information. Accordingly, the signaling overhead of resource allocation information can be reduced.

Alternatively, when a resource allocation request is received from a member terminal belonging to a sidelink group, the GC transmitting terminal may transmit resource allocation information. A resource region (eg, a resource set) may be divided into units of time and frequency resources having a constant size. A resource region (eg, a resource set, time and frequency resources) may be divided by a certain resource pattern. That is, the division unit of the resource region may be a “time and frequency resource” or a “resource pattern”. In this case, the GC transmitting terminal may allocate one or more resource regions to each member terminal. When a plurality of resource regions are allocated, the member terminal may randomly select a resource region(s) from among the plurality of resource regions, and may transmit data using the selected resource region(s).

11 is a conceptual diagram illustrating a first embodiment of a resource pattern for time and frequency resources.

Referring to FIG. 11 , a resource region (eg, a resource set) may be divided into time and frequency resources having a constant size. For example, the TF may be one time and frequency resource having a constant size. TF may be set to be randomly distributed according to a specific pattern in the time and frequency domains. Each of TF0, TF1, TF2, TF3, TF4, TF5, TF6, TF7, and TF8 may be one resource pattern. One or more resource patterns may be allocated to each terminal (eg, each member terminal). Information on one or more resource patterns may be included in resource allocation information (eg, resource coordination information). The UE may randomly select a resource from within the allocated resource pattern(s), and may transmit actual data using the selected resource. The above-described method of setting and transmitting resource allocation information (eg, resource coordination information) may be applicable not only to groupcast communication but also to unicast communication and/or broadcast communication. In unicast communication, the transmitting terminal may transmit resource allocation information to the receiving terminal using PC5-RRC signaling.

In a scenario supporting unicast communication, groupcast communication, and broadcast communication, for sidelink communication between terminals, a terminal performing a resource coordination and/or allocation function (hereinafter referred to as a "coordination terminal") is configured may be, and the coordinating terminal may perform a role of coordinating and/or allocating resources for sidelink communication between terminals. The coordinating terminal may be a transmitting terminal or a receiving terminal. The coordinating terminal may be the above-described GC transmitting terminal. Alternatively, the coordinating terminal may be a third terminal other than the transmitting terminal and the receiving terminal. The third terminal may be selected from terminals adjacent to the transmitting terminal or terminals adjacent to the receiving terminal.

"When the coordinating terminal is the transmitting terminal" or "when the coordinating terminal is selected from among terminals adjacent to the transmitting terminal", the coordinating terminal may inform information about resources suitable for sidelink transmission, and for sidelink transmission It can provide information about unsuitable resources. The above-described information may be transmitted from the coordinating terminal to the transmitting terminal. Inappropriate resources may be referred to as "deprecated resources" or "non-preferred resources". "When the coordinating terminal is the receiving terminal" or "when the coordinating terminal is selected among terminals adjacent to the receiving terminal", the coordinating terminal may inform information about resources suitable for receiving sidelink data, and receiving sidelink data It can provide information about resources that are not suitable for The above-described information may be transmitted from the coordinating terminal to the transmitting terminal.

The above-described information may be set according to available resources and/or the size of a resource pool. For example, when the size of resource adjustment information (eg, resource allocation information) is limited, a type of information suitable for the size may be selected, and the selected information may be transmitted. Whether the above-mentioned information is "information on resources suitable for sidelink communication (eg, sidelink transmission and/or reception)" or "information on resources not suitable for sidelink communication" is to be set in advance. can Information characteristics (eg, “information on resources suitable for sidelink communication” or “information on resources not suitable for sidelink communication”) may include system information, RRC signaling (eg, UE-specific RRC signaling), a MAC control element (CE), and/or control information (eg, downlink control information (DCI), SCI). Alternatively, the information characteristic may be indicated by a separate indicator. In this case, the information characteristic may be signaled together with resource coordination information (eg, resource allocation information).

The transmitting terminal may select resource(s) to be used for sidelink data transmission based on the resource coordination information, and may transmit sidelink data using the selected resource(s). When the resource coordination information is information on resources suitable for sidelink communication (eg, sidelink transmission and/or reception), the resource(s) indicated by the resource coordination information may be used as it is for sidelink data transmission. can In addition, the resource indicated by the resource coordination information is "re-evaluation operation to check whether there is a collision due to aperiodic data transmission of other terminals" or "due to data transmission of higher priority than data of other terminals. It can be used after performing a "pre-emption operation for checking whether the corresponding resource is preempted." In addition, a selection operation (eg, "resource sensing and/or selection operation" or "random selection operation") of a transmission resource of sidelink data within the resources indicated by the resource coordination information may be additionally performed. .

When the resources indicated by the resource coordination information are resources suitable for data transmission, the transmitting terminal may perform data transmission based on the resource coordination information. If the ratio of the resources indicated by the resource coordination information among all the resources is greater than or equal to a specific ratio (eg, X %), the transmitting terminal is in the resources (eg, candidate resources) indicated by the resource coordination information may select resources to be used for actual transmission, and may perform data transmission using the selected resources. If the ratio of the resources indicated by the resource coordination information among all the resources is less than a specific ratio (eg, X %), the transmitting terminal is the resource indicated by the resource coordination information (eg, candidate resources) and All candidate resources that are the sum of candidate resources secured by the additional resource sensing operation may be determined, resources to be used for actual transmission may be selected from among all candidate resources, and data transmission may be performed using the selected resources.

A specific ratio (eg, X %) may be set by system information, RRC signaling (eg, UE-specific RRC signaling), MAC CE, and/or control information (eg, DCI, SCI) have. Alternatively, regardless of whether a ratio of resources (eg, candidate resources) indicated by the resource coordination information among all resources is equal to or greater than a specific ratio, the transmitting terminal selects the resources to be used for actual transmission within the candidate resources. may be selected, and data transmission may be performed using the selected resources. In addition, the transmitting terminal can determine all candidate resources that are the sum of the candidate resources indicated by the resource coordination information and the candidate resources secured by the additional resource sensing operation, and can select resources to be used for actual transmission from among all the candidate resources. and may perform data transmission using the selected resources. Whether to apply the additional candidate resources obtained through the resource sensing operation may be determined according to the sensing capability of the terminal. For example, a terminal that cannot perform a resource sensing operation may select resources to be used for actual transmission by using only resource coordination information. A terminal capable of performing a resource sensing operation may select resources to be used for actual transmission from within resources secured by the resource sensing operation as well as resources indicated by the resource coordination information.

When both the resource coordination information and the result of the additional resource sensing operation exist, priority of resource selection may be required in the resource selection procedure. For example, resources (eg, resource region) indicated by the resource coordination information and resources (eg, resource region) as a result of the additional resource sensing operation (eg, resource region) overlapping resource (s) exists In this case, the overlapped resource(s) may have the highest priority. The overlapped resource(s) may refer to the common resource(s) or the same resource(s) between the resources (eg, resource region) indicated by the resource coordination information and the resources according to the result of the additional resource sensing operation. can The priority of the resource coordination information may be set to be higher than the priority of the result of the additional resource sensing operation, and in this case, the resources indicated by the resource coordination information may be preferentially selected. The priority of the result of the additional resource sensing operation may be set to be higher than the priority of the resource adjustment information, and in this case, resources according to the result of the additional resource sensing operation may be preferentially selected. Resources may be selected from within the union or intersection of the resources indicated by the resource coordination information and the resources according to the result of the additional resource sensing operation. This operation may be performed when the priority of the resource adjustment information is the same as the priority of the result of the additional resource sensing operation.

When the additional resource sensing operation is performed on resources other than the resource region indicated by the resource adjustment information, the priority of the resource adjustment information may be set to be the same as the priority of the result of the additional resource sensing operation. Alternatively, one of the resource coordination information and the result of the additional resource sensing operation may have a relatively high priority. The above-mentioned priority may be preset. For example, the above-mentioned priority may be set by system information, RRC signaling, MAC CE, and/or control information. That is, the information indicating the above-mentioned priority may be transmitted to a terminal (eg, a transmitting terminal).

In addition, whether to apply the additional candidate resources obtained through the resource sensing operation may vary according to the setting of the coordinating terminal. For example, when one coordinating terminal provides resource coordination information to a plurality of terminals, it may be preferable for the plurality of terminals to select resources to be used for actual transmission within the resources indicated by the resource coordination information. . For example, when a plurality of terminals select resources to be used for actual transmission from among the resources indicated by the resource coordination information and the resources secured through the additional resource sensing operation, the resources secured through the additional resource sensing operation Since the adjustment is not performed, resource collision may occur between a plurality of terminals. In this case, it may be preferable for each of the plurality of terminals to select resources by referring only to the resource adjustment information obtained from the coordinating terminal.

It may be difficult for UEs that have received the resource coordination information to determine whether the resource coordination information is information that has been adjusted between a plurality of UEs. Therefore, it may be desirable to signal a separate indicator indicating whether the resource coordination information is information that has been adjusted between a plurality of terminals. For example, an indicator having a size of 1 bit may indicate whether the resource adjustment information is information that is adjusted between a plurality of terminals. That is, the indicator may instruct the terminal to "perform communication in consideration of only the resource coordination information" or "to perform communication in consideration of the result of the additional resource sensing operation as well as the resource coordination information". The indicator may be transmitted in advance to each of the terminals through separate signaling. Alternatively, the indicator may be signaled to each of the terminals together with resource coordination information. Resources coordinated between a plurality of terminals may mean resources in which collision does not occur between the plurality of terminals.

Even when "to perform communication in consideration of the result of the additional resource sensing operation as well as the resource coordination information" is indicated, the terminal without the resource sensing capability may perform the resource selection operation using only the resource coordination information. When the resources indicated by the resource coordination information are resources not suitable for data transmission, the transmitting terminal may perform data transmission based on the resource coordination information. Since the resource indicated by the resource coordination information is not suitable for data transmission, the transmitting terminal may perform a sensing operation in resources other than the resource region indicated by the resource coordination information, and based on the result of the sensing operation to perform a resource selection operation. According to the resource coordination information, the resource area in which the sensing operation is performed may be reduced, and efficient resource sensing may be possible. Since a resource region that is not suitable for data transmission of a specific terminal may be suitable for data transmission of another terminal, efficient resource coordination between terminals may be possible. Alternatively, the transmitting terminal may select resources by performing a random selection operation within resources outside the inappropriate resource region indicated by the resource coordination information.

In another embodiment, the resource coordination information is "information indicating whether a collision actually occurs in the selected resource of the transmitting terminal", "information indicating whether a collision predicted in the selected resource of the transmitting terminal", or "selection of the transmitting terminal Information indicating whether a potential collision occurs in a resource" may be indicated. For example, "when the resource actually used by the transmitting terminal for data transmission collides with the resource used by another terminal" or "When the resource reserved by the transmitting terminal for data transmission overlaps with the resource reserved by another terminal ", the coordinating terminal may identify a collision before or after the actual collision occurs, and may inform the transmitting terminal of collision-related information. If the resource coordination information is collision-related information after a collision occurs, the transmitting terminal receiving the resource coordination information performs a retransmission operation based on the HARQ-ACK (eg, ACK or NACK) received from the receiving terminal. can judge

For example, even when resource collision occurs (eg, even when resource coordination information indicates that actual collision occurs), the transmitting terminal may not perform a retransmission operation when an ACK is received from the receiving terminal. On the other hand, when a NACK is received from the receiving terminal, the transmitting terminal may perform a retransmission operation for the corresponding data. Alternatively, the receiving terminal may not be able to determine whether data reception is successful, and may not be able to transmit the HARQ-ACK for data to the transmitting terminal. In this case, the receiving terminal may determine that resources collide, and may transmit resource collision information to the transmitting terminal. When the resource collision information is received from the receiving terminal, the transmitting terminal may reselect a resource for retransmission, and may perform retransmission of data using the reselected resource. Alternatively, retransmission of data may be performed without resource reselection.

When the HARQ-ACK feedback operation for data transmitted to the receiving terminal is not supported (eg, when the HARQ-ACK feedback operation is disabled), the transmitting terminal has collision information indicated by the resource coordination information A retransmission operation may be performed based on . For example, when the resource coordination information indicates that a resource collision has occurred (eg, when information indicating that an actual collision has occurred is obtained from the resource coordination information), the transmitting terminal may reselect the resource for retransmission. and may perform a retransmission operation on data using the reselected resource. Alternatively, retransmission of data may be performed without resource reselection. On the other hand, when the resource coordination information does not indicate that resource collision has occurred, the transmitting terminal may not perform a retransmission operation. When the resource coordination information indicates information on a possible collision, the transmitting terminal may perform a transmission resource reselection operation based on the resource coordination information.

After the resource coordination information is transmitted, the application time of the resource coordination information may be set differently according to the type of resource coordination information. Specifically, the application time of the resource coordination information may be set differently according to the transmission pattern of the resource coordination information in the time domain. When the resource coordination information is transmitted periodically, the terminal corresponds to the time from the reception of the resource coordination information (eg, the reception time of the resource coordination information + the processing time) to the reception/application time of the resource coordination information of the next cycle A resource selection operation may be performed by applying the resource adjustment information. When resource coordination information is transmitted aperiodically (for example, when resource coordination information is transmitted when a specific event occurs), the terminal receives the corresponding resource until the time when new resource coordination information is received by the occurrence of the next event. A resource selection operation may be performed by applying the adjustment information. When the resource coordination information is transmitted according to a request (eg, a request for data transmission), the terminal receives the resource coordination information after receiving the "time of completion of the initial transmission of the data" or "one or more The resource adjustment information can be applied until the "time of completion of retransmission".

The resource coordination information transmitted by the above-described coordination terminal is "resource information used for actual transmission" or "resource information referenced to select a resource used for actual transmission (eg, recommended resource information or non-recommended resource information) "It could be Signaling methods for transmitting resource coordination information may be important. Accordingly, methods for expanding and applying existing resource reservation information will be proposed in embodiments. The transmitting terminal may transmit "resource information used for actual transmission" or "resource information scheduled to be used for actual transmission" through the control channel. Up to three pieces of resource information may be transmitted through one control channel.

The transmitting terminal may transmit more than three resource information through one control channel. That is, the maximum number of resource information transmittable through one control channel may be expanded. In this case, the existing signaling scheme can be reused, and thus signaling overhead can be reduced. The maximum number (eg, R _MAX ) of resource information (eg, resource region) capable of signaling through resource coordination information may be preset. Alternatively, R _MAX may be configured by system information, RRC signaling, MAC CE, and/or control information (eg, DCI, SCI). Resource information for signaling of resource coordination information may be set differently from resource information used for actual transmission (eg, data transmission). Specifically, the unit of resource information used for signaling of resource coordination information may be set to be larger than the unit of resource information used for actual transmission. Resource information (eg, resource region, subchannel size, resource pool, etc.) may be indicated by resource coordination information.

For example, a subchannel size for signaling of resource coordination information (eg, a subchannel size indicated by resource coordination information) may be set larger than a subchannel size for data transmission, in which case resource coordination Signaling overhead of information can be reduced. When the resource coordination information indicates a recommended resource (eg, a resource suitable for sidelink communication), the resources used for data transmission are "resource sensing and/or selection operation" in the resources indicated by the resource coordination information. " or "random selection operation". When the resource coordination information indicates a non-recommended resource (eg, a resource that is not suitable for sidelink communication), the resources used for actual data transmission are "in resources other than the resource area indicated by the resource coordination information" It may be selected through a “resource sensing and/or selection operation” or a “random selection operation”. In order to set resource information used for signaling of resource coordination information to be different from resource information used for actual data transmission/reception, a resource pool for resource coordination information may be separately set. Resource pool configuration information for resource coordination information may be transmitted by system information and/or RRC signaling. The resource coordination information may be transmitted and received in a resource pool configured for the resource coordination information. Alternatively, parameters for signaling of resource coordination information (eg, subchannel size and/or R _MAX ) may be added to resource pool configuration for existing sidelink communication. The resource pool may be indicated by resource coordination information.

12 is a conceptual diagram illustrating a first embodiment of resource pool setting for resource coordination.

Referring to FIG. 12 , resource information for transmission and reception of actual data may be set independently of resource information for signaling of resource coordination information. For example, a resource for transmission and reception of data may be different from a resource for transmission and reception of resource coordination information. Subchannel #1 may be used for transmission and reception of data, and subchannel #2 may be used for transmission (eg, signaling) of resource coordination information. The size of subchannel #2 may be twice the size of subchannel #1. In this case, the overhead required for signaling of resource coordination information may be reduced. Resources used for data transmission and reception are "resource sensing and / or by performing a "selection operation" or "random selection operation".

The size of subchannel #2 for signaling of resource coordination information may be set to n times the size of subchannel #1 for data transmission and reception. n may be a natural number. The size of subchannel #2 may not be accurately set to n times the size of subchannel #1. In this case, "when the size of the last resource region is greater than or equal to the size of subchannel #1 for data transmission and reception, and the size of the last resource region is less than the size of subchannel #2 for transmission and reception of resource coordination information", the last resource region may be indicated by signaling of resource coordination information, and may be used for data transmission/reception.

The unit of a sensing operation performed by the coordination terminal for signaling of resource coordination information may be a subchannel unit for data transmission/reception, not a subchannel unit for signaling resource coordination information. The resource coordination information may be signaled in units of subchannel #2, and a sensing operation performed by the coordination terminal for transmission of resource coordination information may be performed in units of subchannel #1. In the embodiment shown in FIG. 12 , subchannel #2 may include two subchannels #1. A sensing result in one subchannel #1 among two subchannels #1 may satisfy a resource selection criterion. In this case, some or all of the resources selected according to the sensing result may be used for data transmission/reception. However, when the signaling unit is subchannel #2, the selected resources may not be used.

Accordingly, the resource coordination information may be signaled in units of subchannel #2, and a start position of the resource coordination information may be selected in units of subchannel #1. The overhead by the above-described signaling method may be increased than the signaling overhead when the start position of the resource coordination information is selected in units of subchannel #2. However, when the above-described signaling method is used, if one subchannel #1 among two subchannels #1 in subchannel #2 satisfies the resource selection criterion, one subchannel #1 may be signaled. Therefore, resource efficiency can be improved.

As another method, not only the size of the subchannel through which the resource coordination information is transmitted, but also the starting position of the resource coordination information may be selected in units of subchannel #2, and an offset may be added to the starting position of subchannel #2. The offset may be preferably set in units of subchannel #1. For example, in the embodiment shown in FIG. 12 , subchannel #2 includes two subchannels #1, so an offset having a size of 1 bit may be added, and the value of the offset indicates 0 or 1. can do.

Alternatively, the resource coordination information may be signaled in a bitmap manner. A subchannel for signaling of resource coordination information in a slot (eg, a sidelink slot) may be indicated by a bitmap. A subchannel for signaling of resource coordination information within a certain time interval may be indicated by a bitmap in units of slots. A signaling operation of a two-dimensional bitmap scheme may be performed for all subchannels in slots (eg, sidelink slots) within a predetermined time interval. When a two-dimensional bitmap scheme is used, signaling overhead may increase, and accurate resource coordination information may be provided.

The sidelink HARQ-ACK feedback function may be used for resource coordination and/or allocation operation. In a sidelink group performing groupcast communication, a GC transmitting terminal may configure resources for member terminal(s) based on groupcast HARQ-ACK feedback information. When groupcast HARQ-ACK feedback option 2 is used, each of all member terminals belonging to the groupcast group may transmit HARQ-ACK (eg, HARQ-ACK feedback information) through an individual PSFCH. The GC transmitting terminal may receive the HARQ-ACK of each of the member terminals belonging to the groupcast group, and may check the reception environment for each of the member terminals based on the HARQ-ACK. Accordingly, the GC transmitting terminal may perform resource configuration for the member terminals based on the HARQ-ACK feedback information.

Specifically, the channel state of the member terminal reporting the ACK may be better than the channel state of the member terminal reporting the NACK. The distance between the member UE reporting the ACK and the GC transmitting UE may be closer than the distance between the member UE reporting the NACK and the GC transmitting UE. The GC transmitting terminal may allocate independent resources to adjacent member terminals in order to reduce interference between adjacent member terminals. The distance between the member terminals reporting the NACK and the GC transmitting terminal may be relatively long, and the distance between the member terminals reporting the NACK may be relatively close. Accordingly, the GC transmitting terminal may allocate independent resources to member terminals that have reported the NACK. Since the distance between the set of member terminal(s) reporting ACK and the set of member terminal(s) reporting NACK may be relatively long, interference may not be significant even when overlapping resources are set between the above-described sets. The HARQ-ACK feedback information may be used to establish a pair between member terminals in a sidelink group.

HARQ-ACK feedback information may be used for resource adjustment and/or allocation operation in unicast communication or broadcast communication. When the HARQ-ACK reported by the UE receiving the resource coordination information is ACK, the existing resource coordination information may be maintained. When the HARQ-ACK reported by the UE receiving the resource coordination information is NACK, the resource coordination information may be updated. In order to avoid frequent updating of the resource coordination information, it may be configured to update the resource coordination information when the NACK is continuously reported. The continuous NACK may be “n consecutive NACKs” or “continuous NACKs in the time interval d”. n may be a natural number. The number of consecutive NACKs (n) and/or the time period (d) may be configured by system information, RRC signaling, MAC CE, and/or control information (eg, DCI, SCI). When an ACK occurs while counting the number of NACKs, the number of NACKs or a time period may be initialized. Alternatively, when ACK occurs during counting of the number of NACKs, counting of the number of NACKs may be continued without initialization of the number of NACKs, and when the number of counted NACKs is n or more, resource coordination information may be updated. When an ACK occurs while counting the number of NACKs, the measurement of the time interval length may be continued without initialization of the time interval, and when the measured time interval length is d or more, the resource adjustment information may be updated.

The resource coordination information may be updated according to the request of the terminal. When it is determined that the update of the resource coordination information is necessary, the terminal may request transmission of the updated resource coordination information by transmitting a triggering signal to the coordination terminal. A large amount of power may not be required for the monitoring operation of the triggering signal, and the triggering signal may be stably received by the control terminal. A channel (eg, resource) through which a triggering signal is transmitted may be designed to be the same as or similar to the PSFCH. The PSFCH period may be 1, 2, or 4 slots (eg, logical sidelink (SL) slots). The PSFCH may be repeatedly transmitted in two symbols (eg, two OFDM symbols) in a slot. Among the two symbols, the first symbol may be used for automatic gain control (AGC) for adjusting the received power level of the correct PSFCH.

The PSFCH may be transmitted using a frequency resource region configured by system information and/or RRC signaling in corresponding symbols. In the symbol(s) configured for PSFCH transmission, a frequency resource region not used for PSFCH transmission may be used for transmission of a triggering signal. A frequency resource region used for transmission of a triggering signal may be configured through system information and/or RRC signaling (eg, UE-specific RRC signaling). The transmission resource of the triggering signal within the preset resource region may be implicitly set based on the ID of the coordination terminal, the ID of the terminal receiving the resource adjustment information, and/or the ID of the terminal transmitting the triggering signal. The terminal transmitting the triggering signal may exist independently of the terminal receiving the resource coordination information.

Alternatively, the transmission resource of the triggering signal may be explicitly set by system information, RRC signaling, MAC CE, and/or control information (eg, DCI, SCI). In a PC5-RRC connection establishment procedure between terminals for unicast communication, transmission resource information of a triggering signal may be signaled. "When the resource coordination information is periodically updated", "When a triggering signal is transmitted periodically", "When the update of the existing resource coordination information is not required", or "When additional resource coordination information is not required", A signal (eg, a keeping signal) instructing to prohibit the update of resource coordination information may be transmitted separately.

A channel (eg, resource) through which the keeping signal is transmitted may be designed to be identical to or similar to the PSFCH. When the keeping signal is received, the coordination terminal may stop updating the resource coordination information. In addition, the coordination terminal may not transmit resource coordination information. In this case, signaling overhead and power consumption for updating and transmitting resource coordination information may be reduced. When both the triggering signal and the keeping signal are used, different cyclic shift values may be applied to the triggering signal and the keeping signal, and the triggering signal and the keeping signal may be transmitted in the same resource region. Specifically, when "cyclic shift = 0" of a Zadoff-Chu sequence of length 12 transmitted in a specific resource region is used for transmission of a triggering signal, "cyclic shift = 6" is used for transmission of a keeping signal. can

13 is a conceptual diagram illustrating a first embodiment of a resource setting method for a triggering signal and/or a keeping signal.

Referring to FIG. 13 , in the symbol(s) according to the PSFCH period, a frequency resource region other than the frequency resource region for the PSFCH may be configured for transmission of a triggering signal or a keeping signal. A frequency resource region for transmission of a triggering signal or a keeping signal may be configured as a localized region. As another method, since resource blocks (RBs) in a bandwidth part (BWP) can be set by a bitmap, a frequency resource region for transmission of a triggering signal or a keeping signal can be set by a bitmap.

Alternatively, without separate signaling for resource configuration, a frequency resource region other than the frequency resource region for the PSFCH may be configured as a frequency resource region for transmission of a triggering signal or a keeping signal. The triggering signal and/or the keeping signal in the RB(s) or RB sets (sets) configured with the respective transmission resources of the triggering signal and the keeping signal may be transmitted by applying different cyclic shift values of the same Zadoff-Chu sequence. . In the embodiment shown in Fig. 13, when a Zadoff-Chu sequence of length 12 is used in one RB, "Cyclic shift = 0" may be applied to the triggering signal, and "Cyclic shift = 6" may be applied to the keeping signal. can be applied. When the signaling unit is an RB set including a plurality of RBs, a Zadoff-Chu sequence having a length corresponding to the RB set may be used. In this case, any cyclic shift values along the length corresponding to an RB set other than "cyclic shift = 0" or "cyclic shift = 6" may be used. The cyclic shift value(s) applied to the triggering signal and/or the keeping signal may be set by system information, RRC signaling, MAC CE, and/or control information.

When "resource collision between terminals is detected by a third terminal" or "in case resource collision between terminals is predicted by a third terminal", the third terminal may transmit a collision indicator. The collision indicator may be set independently of the triggering signal and/or the keeping signal. When the collision indicator is transmitted after the resource collision is detected, the time interval between the resource collision identification time and the collision indicator transmission time may be fixed. Alternatively, the above-described time interval may be preset. For example, the above-described time interval may be set by system information, RRC signaling, MAC CE, and/or control information.

Terminals including two terminals in which resource collision has occurred may detect a collision indicator, and may confirm that resource collision has occurred based on the collision indicator. The resource coordination information may be updated based on the collision indicator. Alternatively, retransmission of resource coordination information may be determined based on the collision indicator. When resource collision is expected, a resource reselection operation may be performed. The transmission resource of the collision indicator may be set in the same or similar manner as the transmission resource of the triggering signal and/or the keeping signal. That is, the channel (eg, resource) through which the collision indicator is transmitted may be designed to be the same as or similar to the PSFCH. The collision indicator may be transmitted to be distinct from NACK according to the HARQ-ACK feedback scheme.

Specifically, a cyclic shift for a collision indicator may be added in the PSFCH resource in which the HARQ-ACK feedback is transmitted. For example, when "in the PSFCH resource, cyclic shift = 0 is applied to ACK and cyclic shift = 6 is applied to NACK", "cyclic shift = 8" for a collision indicator may be added. That is, a collision indicator to which "cyclic shift = 8" is applied may be transmitted. The collision indicator for the resource collision that has already occurred may be transmitted according to the NACK reporting period (eg, PSFCH period). Since the collision indicator may be generated faster than the NACK, the transmission period of the collision indicator may be shorter than the reporting period of the NACK (eg, the PSFCH period). The third terminal may be a coordinating terminal or any terminal that has detected a resource collision.

When the collision indicator is received, the coordination terminal may determine that a resource collision has occurred, may update resource coordination information, and may transmit the updated resource coordination information. Alternatively, the coordinating terminal may detect or predict resource collision between terminals without a collision indicator. In this case, the coordination terminal may update the resource coordination information, and may transmit the updated resource coordination information. Here, the coordinating terminal may determine whether a resource collision occurs by performing an interference measurement operation and/or a sensing operation. When a collision between the transmission resource of the transmitting terminal and the transmission resource of another terminal is detected or predicted, the coordination terminal may update the resource coordination information and may transmit the updated resource coordination information. The resource coordination information may be updated to prevent resource conflict. Alternatively, the resource coordination information may be automatically updated after a preset time. A timer for automatic update of resource coordination information may be preset. For example, the timer may be set by system information, RRC signaling, MAC CE, and/or control information. The timer may be transmitted through a control channel together with resource coordination information. When the time according to the timer has elapsed, the coordination terminal may transmit updated resource coordination information.

In the resource coordination information transmission procedure, it may be necessary to set the priority of the resource coordination information. In sidelink communication, priorities of data units may be set differently. When the transmission/reception timing of different data units is the same, a transmission operation or a reception operation on a data unit having a high priority may be performed. For transmission of a data unit having a high priority, a transmission resource of a data unit having a low priority may be pre-empted. Prevents "when the transmission resource of resource coordination information is preempted by transmission of a data unit of another terminal" or "when the transmission of resource coordination information is dropped according to the result of priority comparison with other data units" In order to do this, it may be necessary to set appropriate priorities.

Specifically, the priority may be set differently according to the type of resource coordination information. When the resource coordination information is used for sidelink data transmission (eg, "resources indicated by the resource coordination information are used for data transmission as they are" or "resources within the resources indicated by the resource coordination information") When the resource(s) selected by the selection operation are used for data transmission"), the priority of the corresponding resource adjustment information may be set to the highest. Accordingly, it can be prevented that the transmission of the corresponding resource coordination information is dropped or that the transmission resource of the corresponding resource coordination information is preempted.

Alternatively, a preemption operation between data units may be set, and the set preemption operation may be activated. In this case, the terminal may determine whether the resource is preempted by comparing the priorities of data units. For example, when the priority of data (ie, data unit) of the terminal is lower than the priority of data of other terminals, the terminal may determine that the transmission resource of the corresponding data is preempted. The higher the priority value, the lower the priority of the corresponding data. "If the priority value of data to be transmitted by the terminal is prio _TX , the priority value of data of another terminal is prio _RX , and satisfies prio _TX > prio _RX " can be judged as

The set preemption operation may not be activated. In this case, when the priority of other terminal data is higher than the "preset specific priority" and the "priority of data to be transmitted by the terminal", the terminal may determine that the data transmission resource is preempted. That is, if "the preset specific priority is prio _pre and satisfies prio _RX < prio _pre and prio _TX > prio _RX ", the terminal may determine that the data transmission resource is preempted. Therefore, it may be preferable that the priority for the resource adjustment information is set higher than the preemption threshold. For example, it may be preferable that the priority for resource coordination information is set to the highest.

In order to select a transmission resource of data, the resource coordination information may be used as a reference. That is, the UE may not necessarily use the resource coordination information. In this case, in order to prevent the transmission resource of the resource coordination information from being preempted, it is not necessary to set the priority of the resource coordination information to the highest priority or a priority higher than the preemption threshold. The priority of the resource coordination information may be appropriately set according to the operating environment of the communication system. The resource coordination information may be transmitted through SCI (eg, 1st SCI, 2nd SCI, or a new control channel) other than PSSCH. By applying the above-mentioned priority, the priority of the resource adjustment information may be set to be the same as the priority of the data.

The methods according to the present invention may be implemented in the form of program instructions that can be executed by various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the computer-readable medium may be specially designed and configured for the present invention, or may be known and available to those skilled in the art of computer software.

Examples of computer-readable media include hardware devices specially configured to store and carry out program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as at least one software module to perform the operations of the present invention, and vice versa.

Although it has been described with reference to the above embodiments, it will be understood by those skilled in the art that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. will be able

Claims (20)

A method of operating a transmitting terminal in a communication system, comprising:
Receiving resource coordination (coordination) information;
selecting a resource for sidelink communication based on the resource coordination information; and
Transmitting data to one or more receiving terminals using the selected resource,
The method of operating a transmitting terminal, wherein the resource coordination information is one of preferred resource information and non-preferred resource information for the sidelink communication. The method according to claim 1,
The method of operation of the transmitting terminal,
The method of operating a transmitting terminal, further comprising receiving an indicator indicating that the resource coordination information is the preferred resource information or the non-preferred resource information. The method according to claim 1,
When the resource coordination information is the preference resource information, the resource for the sidelink communication is selected within a first resource region indicated by the resource coordination information, the operating method of the transmitting terminal. The method according to claim 1,
When the resource coordination information is the non-preferred resource information, the resource for the sidelink communication is selected from within resources other than the first resource region indicated by the resource coordination information. The method according to claim 1,
The step of selecting a resource for the sidelink communication comprises:
performing a resource sensing operation; and
When an overlapping resource exists between the first resource region indicated by the resource coordination information and the second resource region according to the result of the resource sensing operation, the sidelink in the first resource region or the second resource region A method of operating a transmitting terminal comprising the step of selecting the overlapped resource for communication. 6. The method of claim 5,
The step of selecting a resource for the sidelink communication comprises:
When the first resource region is different from the second resource region and the priority of the resource adjustment information is higher than the priority of the result of the resource sensing operation, the resource for the sidelink communication in the first resource region A method of operating a transmitting terminal, comprising the step of preferentially selecting. 6. The method of claim 5,
The step of selecting a resource for the sidelink communication comprises:
When the first resource region is different from the second resource region and the priority of the resource adjustment information is lower than the priority of the result of the resource sensing operation, the resource for the sidelink communication in the second resource region A method of operating a transmitting terminal, comprising the step of preferentially selecting. 6. The method of claim 5,
The method of operation of the transmitting terminal,
The method of operating a transmitting terminal, further comprising: receiving a message including at least one of priority information of the resource coordination information and priority information of a result of the resource sensing operation. The method according to claim 1,
The method of operating a transmitting terminal, wherein the maximum number of resource regions indicated by the resource coordination information is three or more. The method according to claim 1,
The method of operating a transmitting terminal, wherein the size of the subchannel indicated by the resource coordination information is set to be different from the size of the subchannel through which the data is transmitted and received. The method according to claim 1,
A resource pool indicated by the resource coordination information is independently configured, and the resource coordination information is received within the resource pool. The method according to claim 1,
So that the transmission resource of the resource coordination information is not pre-emption, the resource coordination information has a high priority, the operating method of the transmitting terminal. The method according to claim 1,
The method of operation of the transmitting terminal,
The method of operation of the transmitting terminal further comprising the step of periodically receiving the updated resource coordination information. The method according to claim 1,
The method of operation of the transmitting terminal,
Further comprising the step of receiving updated resource coordination information according to the occurrence of an event or an update request, the operating method of the transmitting terminal. As a transmitting terminal,
processor;
a memory in electronic communication with the processor; and
including instructions stored in the memory;
When the instructions are executed by the processor, the instructions cause the transmitting terminal to
receive resource coordination information;
select a resource for sidelink communication based on the resource coordination information; and
operative to cause transmission of data to one or more receiving terminals using the selected resource;
The resource coordination information is one of preferred resource information and non-preferred resource information for the sidelink communication, the transmitting terminal. 16. The method of claim 15,
The instructions are the sending terminal,
further operative to cause receiving an indicator indicating that the resource coordination information is the preferred resource information or the non-preferred resource information,
When the resource coordination information is the preference resource information, the resource for the sidelink communication is selected within the first resource region indicated by the resource coordination information, and when the resource coordination information is the non-preferred resource information, the A resource for sidelink communication is selected from within resources other than the first resource region indicated by the resource coordination information. 16. The method of claim 15,
When selecting a resource for the sidelink communication, the instructions
perform a resource sensing operation; and
When an overlapping resource exists between the first resource region indicated by the resource coordination information and the second resource region according to the result of the resource sensing operation, the sidelink in the first resource region or the second resource region and cause selecting the overlapped resource for communication. 18. The method of claim 17,
When selecting a resource for the sidelink communication, the instructions
When the first resource region is different from the second resource region and the priority of the resource adjustment information is higher than the priority of the result of the resource sensing operation, the resource for the sidelink communication in the first resource region A transmitting terminal operative to cause a preferential selection. 18. The method of claim 17,
When selecting a resource for the sidelink communication, the instructions
When the first resource region is different from the second resource region and the priority of the resource adjustment information is lower than the priority of the result of the resource sensing operation, the resource for the sidelink communication in the second resource region A transmitting terminal operative to cause a preferential selection. 16. The method of claim 15,
The maximum number of resource regions indicated by the resource adjustment information is three or more, and the size of the subchannel indicated by the resource adjustment information is set to be different from the size of the subchannel through which the data is transmitted and received.

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