KR20200099087A - Methods for controlling sidelink communication and apparatuses thereof - Google Patents

Abstract

The present disclosure relates to a technique for controlling sidelink communication. According to an aspect of the present invention, a method of a terminal for performing sidelink communication and an apparatus thereof may be provided. The method comprises the steps of: receiving, from a base station, simultaneous use mode configuration information for configuring to use different radio resource allocation schemes of a first mode and a second mode simultaneously; and performing sidelink communication with another terminal using a radio resource allocated by simultaneously using the first mode and the second mode based on the simultaneous use mode configuration information.

Description

Method and apparatus for controlling sidelink communication TECHNICAL FIELD

The present disclosure relates to a technique for controlling sidelink communication.

There are demands for large-capacity data processing, high-speed data processing, and various service demands using wireless terminals in vehicles and industrial sites. As described above, there is a need for a technology for a high-speed and large-capacity communication system capable of processing various scenarios and large-capacity data, such as video, wireless data, and machine-type communication data, beyond a simple voice-oriented service.

To this end, ITU-R discloses the requirements for adopting the IMT-2020 international standard, and research on next-generation wireless communication technology to meet the requirements of IMT-2020 is in progress.

In particular, 3GPP is conducting research on the LTE-Advanced Pro Rel-15/16 standard and the NR (New Radio Access Technology) standard in parallel to satisfy the IMT-2020 requirements referred to as 5G technology. It plans to receive approval as the next generation wireless communication technology.

In 5G technology, it can be applied and used in autonomous vehicles. To do this, it is necessary to apply 5G technology to vehicle communication (Vehicle to everything, V2X), and high-speed transmission and reception is required while ensuring high reliability for increased data for autonomous driving.

In addition, in order to satisfy the driving scenario of various autonomous vehicles such as platoon driving, various data communication such as multicast data transmission and reception as well as multiple unicast data transmission and reception using vehicle communication must be guaranteed.

To this end, it is necessary for the terminal to perform vehicle communication simultaneously using a plurality of vehicle communication radio resources in the same time period. However, in the related art, technical support for performing a plurality of vehicle communication in the same time period has not been disclosed at all.

The present embodiments are intended to propose a method and apparatus for supporting a plurality of sidelink communication in the same time period.

In one aspect, in a method for a terminal to perform sidelink communication, receiving from a base station simultaneous use mode configuration information for configuring a first mode and a second mode, which are different radio resource allocation schemes, to be used simultaneously and at the same time It is possible to provide a method including performing sidelink communication with another terminal by using a radio resource allocated by simultaneously using a first mode and a second mode based on the usage mode configuration information.

In another aspect, in a method of controlling sidelink communication by a base station, transmitting configuration information of a simultaneous use mode to a terminal to configure a first mode and a second mode, which are different radio resource allocation schemes, to be used simultaneously, and the terminal Receiving buffer status information for sidelink communication from the terminal, and transmitting radio resource information for sidelink communication to the terminal based on the buffer status information, wherein the terminal includes the first It is possible to provide a method of performing sidelink communication with another terminal using a radio resource allocated by simultaneously using a mode and a second mode.

In another aspect, a receiver for receiving configuration information from a base station and a simultaneous use mode for configuring a terminal performing sidelink communication to simultaneously use the first mode and the second mode, which are different radio resource allocation schemes. It is possible to provide a terminal device including a control unit for controlling sidelink communication with other terminals by using radio resources allocated by simultaneously using a first mode and a second mode based on configuration information.

In another aspect, in the base station for controlling sidelink communication, from a transmitter and a terminal for transmitting configuration information of a simultaneous use mode to a terminal to configure a first mode and a second mode, which are different radio resource allocation schemes, to be used simultaneously And a receiving unit for receiving buffer status information for sidelink communication, wherein the transmitting unit transmits radio resource information for sidelink communication to the terminal based on the buffer status information, and the terminal is It is possible to provide a base station apparatus that performs sidelink communication with other terminals by using radio resources allocated by simultaneously using the first mode and the second mode.

According to the present embodiments, it is possible to provide an effect of supporting a plurality of sidelink communication in the same time period.

1 is a diagram schematically illustrating a structure of an NR wireless communication system to which the present embodiment can be applied.
2 is a diagram for explaining a frame structure in an NR system to which this embodiment can be applied.
3 is a diagram illustrating a resource grid supported by a radio access technology to which the present embodiment can be applied.
4 is a diagram for explaining a bandwidth part supported by a wireless access technology to which the present embodiment can be applied.
5 is a diagram illustrating a synchronization signal block in a wireless access technology to which the present embodiment can be applied.
6 is a diagram for explaining a random access procedure in a radio access technology to which the present embodiment can be applied.
7 is a diagram for explaining CORESET.
8 is a diagram for exemplifying symbol level alignment between different SCSs in a radio access technology to which the present embodiment can be applied.
9 is a diagram for describing various scenarios for vehicle communication.
10 is a diagram for explaining a type of vehicle communication to which the present embodiment can be applied.
11 is a diagram illustrating an exemplary architecture of a V2X communication system in an LTE system.
12 is a diagram for explaining a terminal operation according to an embodiment.
13 is a diagram for describing a terminal operation according to another embodiment.
14 is a diagram for describing an operation of a base station according to an embodiment.
15 is a diagram illustrating a configuration of a terminal according to an embodiment.
16 is a diagram for describing a configuration of a base station according to an embodiment.

Hereinafter, some embodiments of the present technical idea will be described in detail with reference to exemplary drawings. In adding reference numerals to elements of each drawing, the same elements may have the same numerals as possible even if they are indicated on different drawings. In addition, in describing the technical idea, when it is determined that a detailed description of a related known configuration or function may obscure the gist of the technical idea, the detailed description may be omitted.

In addition, terms such as first, second, A, B, (a), and (b) may be used in describing the components of the present embodiments. These terms are only for distinguishing the component from other components, and the nature, order, order, or number of the component is not limited by the term. When a component is described as being "connected", "coupled" or "connected" to another component, the component may be directly connected or connected to that other component, but other components between each component It is to be understood that is "interposed", or that each component may be "connected", "coupled" or "connected" through other components.

In addition, terms and technical names used in the present specification are for describing specific embodiments, and the technical idea is not limited thereto. The terms described below may be interpreted as meanings generally understood by those of ordinary skill in the technical field to which the present technical idea belongs unless otherwise defined. When the corresponding term is an incorrect technical term that does not accurately express the present technical idea, it will be replaced with a technical term that can be correctly understood by those skilled in the art to be understood. In addition, general terms used in the present specification should be interpreted as defined in the dictionary or according to the context before and after, and should not be interpreted as an excessively reduced meaning.

The wireless communication system in the present specification refers to a system for providing various communication services such as voice and data packets using radio resources, and may include a terminal, a base station, and a core network.

The embodiments disclosed below can be applied to a wireless communication system using various wireless access technologies. For example, the present embodiments are CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (timedivision multiple access), OFDMA (orthogonal frequency division multiple access), SC-FDMA (singlecarrier frequency division multiple access) It can be applied to various wireless access technologies such as. CDMA may be implemented with a radio technology such as universal terrestrial radio access (UTRA) or CDMA2000. TDMA may be implemented using a radio technology such as global system for mobile communications (GSM)/general packet radio service (GPRS)/enhanced data rates for GSM evolution (EDGE). OFDMA may be implemented with a wireless technology such as IEEE (institute of electrical and electronics engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (evolved UTRA), and the like. IEEE 802.16m is an evolution of IEEE 802.16e and provides backward compatibility with a system based on IEEE 802.16e. UTRA is part of a universal mobile telecommunications system (UMTS). 3rd generation partnership project (3GPP) long term evolution (LTE) is a part of evolved UMTS (E-UMTS) using evolved-UMTSterrestrial radio access (E-UTRA), and employs OFDMA in downlink and SC- in uplink. Adopt FDMA. As described above, the present embodiments may be applied to a wireless access technology currently disclosed or commercialized, and may be applied to a wireless access technology currently being developed or to be developed in the future.

Meanwhile, a terminal in the present specification is a generic concept that refers to a device including a wireless communication module that performs communication with a base station in a wireless communication system, and is a UE in WCDMA, LTE, HSPA, and IMT-2020 (5G or New Radio). In addition to (User Equipment), it should be interpreted as a concept that includes all of MS (Mobile Station), UT (User Terminal), SS (Subscriber Station), and wireless device in GSM. In addition, the terminal may be a user's portable device such as a smart phone according to the usage type, and in the V2X communication system, it may mean a vehicle, a device including a wireless communication module in the vehicle, and the like. In addition, in the case of a machine type communication system, it may mean an MTC terminal or an M2M terminal equipped with a communication module so that machine type communication is performed.

The base station or cell of the present specification refers to the end of communication with the terminal in terms of the network, and Node-B (Node-B), eNB (evolved Node-B), gNB (gNode-B), LPN (Low Power Node), Sector, Site, various types of antennas, BTS (Base Transceiver System), Access Point, Point (e.g., Transmit Point, Receiving Point, Transmitting Point), Relay Node ), a mega cell, a macro cell, a micro cell, a pico cell, a femto cell, a remote radio head (RRH), a radio unit (RU), and a small cell.

In the various cells listed above, since there is a base station controlling each cell, the base station can be interpreted in two meanings. 1) In relation to the radio area, the device itself may provide a mega cell, a macro cell, a micro cell, a pico cell, a femto cell, and a small cell, or 2) the radio area itself may be indicated. In 1), all devices that are controlled by the same entity that provide a predetermined wireless area are controlled by the same entity, or all devices that interact to form a wireless area in collaboration are instructed to the base station. A point, a transmission/reception point, a transmission point, a reception point, etc. may be an embodiment of a base station according to the configuration method of the wireless area. In 2), it is possible to instruct the base station to the radio region itself that receives or transmits a signal from the viewpoint of the user terminal or the viewpoint of a neighboring base station.

In the present specification, a cell refers to a component carrier having coverage of a signal transmitted from a transmission/reception point or a coverage of a signal transmitted from a transmission/reception point, and the transmission/reception point itself. I can.

Uplink (Uplink, UL, or uplink) refers to a method of transmitting and receiving data to a base station by a UE, and downlink (Downlink, DL, or downlink) refers to a method of transmitting and receiving data to a UE by a base station. The downlink may refer to a communication or communication path from multiple transmission/reception points to the terminal, and the uplink may refer to a communication or communication path from the terminal to multiple transmission/reception points. In this case, in the downlink, the transmitter may be a part of the multiple transmission/reception points, and the receiver may be a part of the terminal. In addition, in the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of the multiple transmission/reception points.

Uplink and downlink transmit and receive control information through a control channel such as Physical Downlink Control CHannel (PDCCH), Physical Uplink Control CHannel (PUCCH), and the like, and The same data channel is configured to transmit and receive data. Hereinafter, a situation in which signals are transmitted and received through channels such as PUCCH, PUSCH, PDCCH, and PDSCH is expressed in the form of'transmitting and receiving PUCCH, PUSCH, PDCCH and PDSCH'. do.

In order to clarify the description, hereinafter, the present technical idea is mainly described with respect to a 3GPP LTE/LTE-A/NR (New RAT) communication system, but the present technical feature is not limited thereto.

After research on 4G (4th-Generation) communication technology, 3GPP is conducting research on 5G (5th-Generation) communication technology to meet the requirements of ITU-R's next-generation wireless access technology. Specifically, 3GPP is conducting research on LTE-A pro, which has improved LTE-Advanced technology as a 5G communication technology in accordance with the requirements of ITU-R, and a new NR communication technology separate from 4G communication technology. It is expected that both LTE-A pro and NR will be submitted as 5G communication technology, but in the following, for convenience of explanation, these embodiments will be described focusing on NR.

The operation scenario in NR defined various operation scenarios by adding considerations to satellites, automobiles, and new verticals from the existing 4G LTE scenario.In terms of service, eMBB (Enhanced Mobile Broadband) scenario, high terminal density, but wide It is deployed in the range and supports the mMTC (Massive Machine Communication) scenario that requires a low data rate and asynchronous connection, and the URLLC (Ultra Reliability and Low Latency) scenario that requires high responsiveness and reliability and supports high-speed mobility. .

In order to satisfy this scenario, NR discloses a wireless communication system to which a new waveform and frame structure technology, a low latency technology, a mmWave support technology, and a forward compatible provision technology are applied. In particular, in the NR system, various technical changes are proposed in terms of flexibility to provide forward compatibility. Main technical features will be described below with reference to the drawings.

<NR system general>

1 is a diagram schematically showing a structure of an NR system to which this embodiment can be applied.

1, the NR system is divided into 5GC (5G Core Network) and NR-RAN parts, and NG-RAN controls user plane (SDAP/PDCP/RLC/MAC/PHY) and UE (User Equipment). It is composed of gNB and ng-eNB that provide plane (RRC) protocol termination. The gNB or gNB and ng-eNB are interconnected through an Xn interface. The gNB and ng-eNB are each connected to 5GC through the NG interface. The 5GC may include an Access and Mobility Management Function (AMF) in charge of a control plane such as a terminal access and mobility control function, and a User Plane Function (UPF) in charge of a control function for user data. NR includes support for both frequency bands below 6GHz (FR1, Frequency Range 1) and frequencies above 6GHz (FR2, Frequency Range 2).

gNB means a base station that provides NR user plane and control plane protocol termination to a terminal, and ng-eNB means a base station that provides E-UTRA user plane and control plane protocol termination to a terminal. The base station described in the present specification should be understood in a sense encompassing gNB and ng-eNB, and may be used as a means to distinguish between gNB or ng-eNB as necessary.

<NR wave form, numer roller and frame structure>

In NR, a CP-OFDM waveform using a cyclic prefix is used for downlink transmission, and CP-OFDM or DFT-s-OFDM is used for uplink transmission. OFDM technology is easy to combine with MIMO (Multiple Input Multiple Output), and has the advantage of being able to use a low complexity receiver with high frequency efficiency.

On the other hand, in NR, since the requirements for data rate, delay rate, and coverage are different for each of the three scenarios described above, it is necessary to efficiently satisfy the requirements for each scenario through a frequency band constituting an arbitrary NR system. . To this end, a technique for efficiently multiplexing a plurality of different numerology-based radio resources has been proposed.

값이 2의 지수 값으로 사용되어 지수적으로 변경된다.Specifically, the NR transmission neuron is determined based on sub-carrier spacing and CP (Cyclic prefix), based on 15khz as shown in Table 1 below.

The value is used as an exponential value of 2 and changes exponentially.

Subcarrier spacing Cyclic prefix Supported for data Supported for synch 0 15 Normal Yes Yes One 30 Normal Yes Yes 2 60 Normal, Extended Yes No 3 120 Normal Yes Yes 4 240 Normal No Yes

As shown in Table 1 above, the NR numer rollers can be classified into 5 types according to the subcarrier interval. This is different from the fixed subcarrier spacing of 15khz of LTE, one of the 4G communication technologies. Specifically, subcarrier intervals used for data transmission in NR are 15, 30, 60, and 120khz, and subcarrier intervals used for synchronization signal transmission are 15, 30, 12, and 240khz. In addition, the extended CP is applied only to the 60khz subcarrier interval. Meanwhile, a frame structure in NR is defined as a frame having a length of 10 ms consisting of 10 subframes having the same length of 1 ms. One frame can be divided into 5 ms half frames, and each half frame includes 5 subframes. In the case of the 15khz subcarrier interval, one subframe consists of 1 slot, and each slot consists of 14 OFDM symbols.

2 is a diagram for explaining a frame structure in an NR system to which this embodiment can be applied.

Referring to FIG. 2, in the case of a normal CP, a slot is fixedly composed of 14 OFDM symbols, but the length of the slot may vary according to the subcarrier interval. For example, in the case of a newer roller having a 15khz subcarrier interval, a slot is 1ms long and has the same length as the subframe. In contrast, in the case of a newer roller with a 30khz subcarrier spacing, a slot consists of 14 OFDM symbols, but two slots may be included in one subframe with a length of 0.5ms. That is, the subframe and the frame are defined with a fixed time length, and the slot is defined by the number of symbols, and the time length may vary according to the subcarrier interval.

Meanwhile, NR defines a basic unit of scheduling as a slot, and introduces a mini-slot (or sub-slot or non-slot based schedule) in order to reduce the transmission delay of the radio section. If a wide subcarrier spacing is used, the length of one slot is shortened in inverse proportion, so that transmission delay in the radio section can be reduced. The mini-slot (or sub-slot) is for efficient support for the URLLC scenario, and scheduling is possible in units of 2, 4, or 7 symbols.

In addition, unlike LTE, NR defines uplink and downlink resource allocation as a symbol level within one slot. In order to reduce HARQ delay, a slot structure capable of transmitting HARQ ACK/NACK directly within a transmission slot has been defined, and this slot structure is named and described as a self-contained structure.

NR is designed to support a total of 256 slot formats, of which 62 slot formats are used in Rel-15. In addition, a common frame structure constituting an FDD or TDD frame is supported through a combination of various slots. For example, a slot structure in which all symbols of a slot are set to downlink, a slot structure in which all symbols are set to uplink, and a slot structure in which a downlink symbol and an uplink symbol are combined are supported. In addition, NR supports that data transmission is distributed and scheduled in one or more slots. Accordingly, the base station may inform the UE of whether the slot is a downlink slot, an uplink slot, or a flexible slot using a slot format indicator (SFI). The base station can indicate the slot format by indicating the index of the table configured through RRC signaling specifically through the UE, using SFI, and dynamically indicate through Downlink Control Information (DCI) or statically or semi-statically through RRC. May be.

<NR physical resource>

Regarding the physical resource in NR, the antenna port, resource grid, resource element, resource block, bandwidth part, etc. are considered. Can be.

The antenna port is defined so that a channel carrying a symbol on an antenna port can be inferred from a channel carrying another symbol on the same antenna port. When the large-scale property of a channel carrying a symbol on one antenna port can be inferred from a channel carrying a symbol on another antenna port, the two antenna ports are QC/QCL (quasi co-located or quasi co-location) relationship. Here, the wide-range characteristic includes one or more of delay spread, Doppler spread, frequency shift, average received power, and received timing.

3 is a diagram illustrating a resource grid supported by a radio access technology to which the present embodiment can be applied.

Referring to FIG. 3, since the NR supports a plurality of neurons in the same carrier, a resource grid may exist according to each neuron in the resource grid. In addition, the resource grid may exist according to an antenna port, a subcarrier spacing, and a transmission direction.

A resource block consists of 12 subcarriers, and is defined only in the frequency domain. In addition, a resource element consists of one OFDM symbol and one subcarrier. Accordingly, as shown in FIG. 3, the size of one resource block may vary according to the subcarrier interval. In addition, NR defines “Point A” that serves as a common reference point for the resource block grid, a common resource block, and a virtual resource block.

4 is a diagram for explaining a bandwidth part supported by a wireless access technology to which the present embodiment can be applied.

In NR, unlike LTE where the carrier bandwidth is fixed at 20Mhz, the maximum carrier bandwidth is set from 50Mhz to 400Mhz for each subcarrier interval. Therefore, it is not assumed that all terminals use all of these carrier bandwidths. Accordingly, in the NR, as shown in FIG. 4, the terminal can use the bandwidth part by designating the bandwidth part within the carrier bandwidth. In addition, the bandwidth part is associated with one neurology and is composed of a subset of consecutive common resource blocks, and can be dynamically activated over time. The UE is configured with up to four bandwidth parts, respectively, in uplink and downlink, and data is transmitted and received using the active bandwidth part at a given time.

In the case of a paired spectrum, uplink and downlink bandwidth parts are independently set, and in the case of an unpaired spectrum, unnecessary frequency re-tuning between downlink and uplink operations is prevented. For this purpose, the downlink and uplink bandwidth parts are set in pairs to share a center frequency.

<NR initial connection>

In NR, the terminal accesses the base station and performs cell search and random access procedures to perform communication.

Cell search is a procedure in which a terminal synchronizes with a cell of a corresponding base station, obtains a physical layer cell ID, and obtains system information by using a synchronization signal block (SSB) transmitted by a base station.

5 is a diagram illustrating a synchronization signal block in a wireless access technology to which the present embodiment can be applied.

Referring to FIG. 5, an SSB consists of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) occupying 1 symbol and 127 subcarriers, respectively, and a PBCH spanning 3 OFDM symbols and 240 subcarriers.

The terminal receives the SSB by monitoring the SSB in the time and frequency domain.

SSB can be transmitted up to 64 times in 5ms. A plurality of SSBs are transmitted in different transmission beams within 5 ms time, and the UE performs detection on the assumption that SSBs are transmitted every 20 ms period based on one specific beam used for transmission. The number of beams that can be used for SSB transmission within 5 ms time may increase as the frequency band increases. For example, up to 4 SSB beams can be transmitted under 3GHz, and up to 8 in a frequency band of 3 to 6GHz, and a maximum of 64 different beams in a frequency band of 6GHz or higher can be used to transmit SSBs.

Two SSBs are included in one slot, and the start symbol and the number of repetitions in the slot are determined according to the subcarrier interval as follows.

Meanwhile, the SSB is not transmitted at the center frequency of the carrier bandwidth, unlike the conventional LTE SS. That is, the SSB may be transmitted even in a place other than the center of the system band, and a plurality of SSBs may be transmitted in the frequency domain when broadband operation is supported. Accordingly, the UE monitors the SSB by using a synchronization raster, which is a candidate frequency location for monitoring the SSB. The carrier raster and synchronization raster, which are information on the center frequency of the channel for initial access, have been newly defined in NR, and the synchronization raster has a wider frequency interval than the carrier raster to support fast SSB search of the terminal. I can.

The UE can acquire the MIB through the PBCH of the SSB. The MIB (Master Information Block) includes minimum information for the terminal to receive remaining system information (RMSI, Remaining Minimum System Information) broadcast by the network. In addition, PBCH is information about the location of the first DM-RS symbol in the time domain, information for the UE to monitor SIB1 (e.g., SIB1 neurology information, information related to SIB1 CORESET, search space information, PDCCH Related parameter information, etc.), offset information between the common resource block and the SSB (the position of the absolute SSB in the carrier is transmitted through SIB1), and the like. Here, the SIB1 neurology information is equally applied to messages 2 and 4 of the random access procedure for accessing the base station after the terminal completes the cell search procedure.

The aforementioned RMSI means SIB1 (System Information Block 1), and SIB1 is broadcast periodically (ex, 160 ms) in a cell. SIB1 includes information necessary for the UE to perform an initial random access procedure, and is periodically transmitted through the PDSCH. In order for the UE to receive SIB1, it is necessary to receive newer roller information used for SIB1 transmission and CORESET (Control Resource Set) information used for SIB1 scheduling through the PBCH. The UE checks scheduling information for SIB1 using SI-RNTI in CORESET, and acquires SIB1 on the PDSCH according to the scheduling information. SIBs other than SIB1 may be periodically transmitted or may be transmitted according to the request of the terminal.

6 is a diagram for explaining a random access procedure in a radio access technology to which the present embodiment can be applied.

Referring to FIG. 6, when the cell search is completed, the UE transmits a random access preamble for random access to the base station. The random access preamble is transmitted through the PRACH. Specifically, the random access preamble is transmitted to the base station through a PRACH consisting of consecutive radio resources in a specific slot that is periodically repeated. In general, when a terminal initially accesses a cell, a contention-based random access procedure is performed, and when a random access is performed for beam failure recovery (BFR), a contention-free random access procedure is performed.

The terminal receives a random access response to the transmitted random access preamble. The random access response may include a random access preamble identifier (ID), a UL Grant (uplink radio resource), a temporary C-RNTI (Temporary Cell-Radio Network Temporary Identifier), and a TAC (Time Alignment Command). Since one random access response may include random access response information for one or more terminals, the random access preamble identifier may be included to inform which terminal the included UL Grant, temporary C-RNTI, and TAC are valid. The random access preamble identifier may be an identifier for the random access preamble received by the base station. TAC may be included as information for the UE to adjust uplink synchronization. The random access response may be indicated by a random access identifier on the PDCCH, that is, a Random Access-Radio Network Temporary Identifier (RA-RNTI).

Upon receiving a valid random access response, the terminal processes information included in the random access response and performs scheduled transmission to the base station. For example, the UE applies TAC and stores a temporary C-RNTI. Also, by using UL Grant, data stored in the buffer of the terminal or newly generated data is transmitted to the base station. In this case, information for identifying the terminal should be included.

Finally, the terminal receives a downlink message for resolving contention.

<NR CORESET>

The downlink control channel in NR is transmitted in CORESET (Control Resource Set) having a length of 1 to 3 symbols, and transmits uplink/downlink scheduling information, SFI (Slot Format Index), and TPC (Transmit Power Control) information. .

In this way, NR introduced the concept of CORESET to secure system flexibility. CORESET (Control Resource Set) means a time-frequency resource for a downlink control signal. The terminal may decode the control channel candidate using one or more search spaces in the CORESET time-frequency resource. A QCL (Quasi CoLocation) assumption for each CORESET is set, and this is used to inform the characteristics of the analog beam direction in addition to the delay spread, Doppler spread, Doppler shift, and average delay, which are characteristics assumed by conventional QCL.

7 is a diagram for explaining CORESET.

Referring to FIG. 7, CORESET may exist in various forms within a carrier bandwidth within one slot, and CORESET may consist of up to 3 OFDM symbols in the time domain. In addition, CORESET is defined as a multiple of 6 resource blocks up to the carrier bandwidth in the frequency domain.

The first CORESET is indicated through the MIB as part of the initial bandwidth part configuration so that additional configuration information and system information can be received from the network. After establishing the connection with the base station, the terminal may receive and configure one or more CORESET information through RRC signaling.

In this specification, frequencies, frames, subframes, resources, resource blocks, regions, bands, subbands, control channels, data channels, synchronization signals, various reference signals, various signals, or various messages related to NR (New Radio) Can be interpreted as a meaning used in the past or present, or in various meanings used in the future.

New Radio (NR)

As described above, NR, which has been recently conducted in 3GPP, has been designed to satisfy various QoS requirements required for each subdivided and specified usage scenario, as well as an improved data transmission rate compared to LTE. In particular, eMBB (enhancement mobile broadband), mMTC (massive MTC), and URLLC (Ultra Reliable and Low Latency Communications) were defined as representative usage scenarios of NR, and as a method to satisfy the requirements of each usage scenario, it is more flexible than LTE ( flexible) frame structure design is required. Each usage scenario has different requirements for data rates, latency, reliability, and coverage. Accordingly, as a method for efficiently satisfying the requirements for each usage scenario through the frequency band constituting an arbitrary NR system, radio resource units (eg, subcarrier spacing, subframe, TTI, etc.) based on different numerology (eg subcarrier spacing, subframe, TTI, etc.) unit) is designed to be efficiently multiplexed.

For example, discussion has been made on a method of multiplexing and supporting numerology with different subcarrier spacing values based on TDM, FDM or TDM/FDM through one or more NR component carrier(s). lost. In addition, in configuring a scheduling unit in the time domain, discussion has been made on a method of supporting more than one time unit. In this regard, in NR, a subframe is defined as a kind of time domain structure. As a reference numerology for defining the corresponding subframe duration, it was decided to define a single subframe duration consisting of 14 OFDM symbols of normal CP overhead based on 15kHz Sub-Carrier Spacing (SCS) same as LTE. Accordingly, in NR, the subframe has a time duration of 1 ms. However, unlike LTE, a subframe of NR is an absolute reference time duration, and slots and mini-slots may be defined as time units that are the basis of actual uplink/downlink data scheduling. In this case, the number of OFDM symbols constituting the slot and the y value were determined to have a value of y=14 regardless of the SCS value in the case of normal CP.

Accordingly, an arbitrary slot consists of 14 symbols. In addition, depending on the transmission direction of the corresponding slot, all symbols may be used for DL transmission, all symbols may be used for UL transmission, or DL portion + (gap) + UL portion. have.

In addition, in any numerology (or SCS), a mini-slot consisting of fewer symbols than the aforementioned slot is defined. A short time-domain scheduling interval for transmitting/receiving uplink/downlink data based on a mini-slot may be set, or a long time-domain scheduling interval for transmitting/receiving uplink/downlink data through slot aggregation. have. In particular, in the case of transmitting/receiving latency-sensitive data such as URLLC, it is difficult to satisfy the latency requirement when 1ms (14 symbols)-based slot unit scheduling defined in a numerology-based frame structure with a small SCS value such as 15 kHz is performed. I can. Accordingly, by defining a mini-slot composed of fewer OFDM symbols than a slot composed of 14 symbols, scheduling capable of satisfying the requirements of URLLC can be performed based on this.

8 is a diagram for exemplifying symbol level alignment between different SCSs in a radio access technology to which the present embodiment can be applied.

Referring to FIG. 8, as described above, numerology having different SCS values in one NR carrier may be multiplexed in a TDM and/or FDM scheme to support. Therefore, a method of scheduling data according to latency requirements based on the slot (or mini-slot) length defined for each numerology is also considered. For example, when the SCS is 60 kHz, the symbol length is reduced by about 1/4 compared to the SCS 15 kHz, so when one slot is configured with the same 14 OFDM symbols, the 15 kHz-based slot length becomes 1 ms. On the other hand, the slot length based on 60 kHz is reduced to about 0.25 ms.

<LTE V2X communication>

In the existing LTE system, radio channels and radio protocols for direct communication (ie, sidelink) between terminals were designed to provide direct communication between terminals and V2X (especially V2V) services.

Regarding the sidelink, PSSS/SSSS, which is a synchronization signal for synchronization between a wireless sidelink transmitting end and a receiving end, and PSBCH (Physical Sidelink Broadcasting Channel) for transmitting and receiving a related sidelink MIB (Master Information Block) are defined, and discovery information Designs were made for a physical sidelink discovery channel (PSCCH) for transmission and reception, a physical sidelink control channel (PSCCH) for transmission and reception of sidelink control information (SCI), and a physical sidelink shared channel (PSSCH) for transmission and reception of sidelink data.

In addition, for radio resource allocation for a sidelink, a technique was developed by dividing into mode 1 in which the base station allocates radio resources and mode 2 in which the terminal selects and allocates radio resources from a radio resource pool. In addition, the LTE system required additional technological evolution to satisfy the V2X scenario.

In this environment, 3GPP derived 27 service scenarios related to vehicle recognition in Rel-14 and determined major performance requirements according to road conditions. In addition, in recent Rel-15, six performance requirements were determined by deriving 25 more advanced service scenarios such as platoon driving, advanced driving, and long-distance vehicle sensors.

In order to satisfy these performance requirements, the development of a technology to improve the performance of the sidelink technology developed based on the conventional D2D communication according to the requirements of V2X has been progressed. Particularly, in order to apply to C-V2X (Cellular-V2X), technology that improves the physical layer design of the sidelink to be suitable for high-speed environments, resource allocation technology, and synchronization technology can be selected as major research technologies.

The sidelink described below refers to a link used for D2D communication developed after 3GPP Rel-12 and V2X communication after Rel-14, and each channel term, synchronization term, resource term, etc. are D2D communication requirements, V2X Regardless of the Rel-14, 15 requirements, they are described in the same terms.

9 is a diagram for describing various scenarios for vehicle communication.

Referring to FIG. 9, a V2X terminal (denoted as a vehicle, but variously settable such as a user terminal) may be located within the coverage of a base station (eNB or gNB or ng-eNB), or may be located outside the base station coverage. For example, communication may be performed between terminals within the coverage of the base station (UE N-1, UE G-1, and UE X), and between a terminal within the base station coverage and an external terminal (ex, UE N-1, UE N- 2) can also perform communication. Alternatively, communication may be performed between terminals (ex, UE G-1, UE G-2) outside the coverage of the base station.

Meanwhile, the communication target may be classified as follows based on the vehicle terminal.

10 is a diagram for explaining a type of vehicle communication to which the present embodiment can be applied.

Referring to FIG. 10, by providing the vehicle with access to a mobile communication network (eg, LTE or LTE-Advanced), the vehicle can be connected to the Internet and other vehicles. V2X (Vehicle to Everything) communication includes the following four types.

-V2V (Vehicle to Vehicle) Communication: Communication between vehicle and vehicle

-V2I (Vehicle to Infrastructure) Communication: Communication between vehicle and infrastructure

-V2N (Vehicle to Network) Communication: Communication between vehicle and network

-V2P (Vehicle to Pedestrian) Communication: Communication between vehicle and pedestrian

11 is a diagram illustrating an exemplary architecture of a V2X communication system in an LTE system.

Referring to FIG. 11, a V2X service may be provided through a PC5 interface and/or a Uu interface. Support through the PC5 interface was provided through V2X sidelink communication.

Specifically, various V2X communication terminals (UE A to D) are linked through a PC5 interface, and a V2X communication terminal and a V2X control function are linked through a V3 interface. In addition, the V2X application server and the V2X application of each V2X communication terminal are linked through the V1 interface. The V2X communication terminal is linked with a base station (E-UTRAN) through a Uu interface, and the base station is linked with a core network (MME and S/P GW) and an S1 interface. MME and S/P GW are linked with HSS and S6a interface, and HSS is linked with V2X control function and V4 interface. The core network entity is linked with the V2X application server through the SGi interface. On the other hand, the V2X application of each V2X communication terminal is linked to each other through the V5 interface.

In the conventional LTE system, resource allocation of a terminal supporting V2X sidelink communication supported the following two modes.

-Scheduled resource allocation: RRC connection is required for data transmission. The terminal requests transmission resource allocation to the base station, and the base station allocates transmission resources for transmission of sidelink control information and data. For convenience of explanation, hereinafter, a resource allocation mode in which the base station allocates sidelink resources is referred to as a first mode. This is only for convenience of description and may be replaced with another name.

-Terminal autonomous resource allocation: The terminal selects a resource by itself within the pre-configured sidelink resource pool, and selects a transmission format for transmitting sidelink control information and data. For convenience of explanation, hereinafter, a resource allocation mode in which the terminal selects a sidelink resource in the sidelink resource pool according to a predetermined criterion is indicated as a second mode. This is only for convenience of description and may be replaced with another name.

In addition, the above-described first mode and second mode cannot be repeatedly applied within the same time period. That is, in the related art, any terminal could operate only according to one of the resource allocation modes of the first mode and the second mode at an arbitrary time.

NR V2X

3GPP approved the NR V2X study item to support advanced V2X services such as vehicles platooning, extended sensors, advanced driving, and remote driving based on NR. NR V2X does not intend to replace the service provided by LTE V2X, and it is assumed that the enhanced V2X service complements LTE V2X and supports interworking with LTE V2X. In addition, this item includes sidelink unicast, sidelink groupcast, and sidelink broadcast support in the study range.

In NR V2X, the resource allocation scheme may support a first mode in which the base station performs scheduling for communication resources between terminals and a second mode scheme in which the terminal autonomously selects a resource from a resource pool. In addition, the second mode may be classified into one or more of the following detailed forms.

-Mode 2-a: UE autonomously selects sidelink resource for transmission.

-Mode 2-b: The UE supports sidelink resource selection for other UE(s) (UE assists sidelink resource selection for other UE(s)).

-Mode 2-c: UE is configured with an NR configuration grand for sidelink transmission (UE is configured with NR configured grant (type-1 like) for sidelink transmission).

-Mode 2-d: UE schedules sidelink transmissions of other UEs (UE schedules sidelink transmissions of other UEs)

As such, NR V2X is also expected to basically follow the conventional LTE V2X resource allocation scheme. Therefore, one terminal can operate in only one resource allocation mode at a specific time. In this case, in providing various V2X services at the same time in the terminal, there is a possibility that it is difficult to satisfy improved service requirements and service quality.

The present embodiments devised to solve this problem propose a method and apparatus for effectively performing sidelink communication by a terminal using two resource allocation modes at the same time.

Hereinafter, the aforementioned vehicle communication, V2X communication, and D2D communication will be described using the term sidelink communication, which is for convenience of description and should be understood as including all operations of transmitting or receiving data between terminals. In addition, the above-described definitions of the first mode and the second mode are for convenience of understanding only, and the present disclosure may be applied to the first mode and the second mode if different random resource allocation methods are used. In addition, two or more different random resource allocation schemes may exist, and two are described as an example in the present disclosure, but the same may be applied even when three or more modes exist.

Meanwhile, this embodiment can be applied to an NR base station and an NR terminal. In addition, this embodiment can be applied to an LTE base station and an LTE terminal. Alternatively, this embodiment may be applied to an eLTE base station and an LTE terminal connected through a 5G system (or 5G Core Network). Of course, this embodiment may be applied to an E-UTRAN NR Dual Connectivity (EN-DC) terminal or a NR E-UTRAN Dual Connectivity (NE-DC) terminal that simultaneously provides LTE and NR wireless connectivity.

12 is a diagram for explaining a terminal operation according to an embodiment.

Referring to FIG. 12, the terminal performing sidelink communication performs a step of receiving from the base station concurrent use mode configuration information for configuring the first mode and the second mode, which are different radio resource allocation schemes, to be used simultaneously. Can be (S1200).

For example, the simultaneous use mode configuration information includes configuration information for configuring a terminal to simultaneously use different sidelink resource allocation modes. As an example, the first mode refers to a resource allocation mode in which radio resources used to perform sidelink communication are allocated from a base station. That is, the first mode refers to a resource allocation mode in which the base station dynamically requests sidelink resource allocation and allocates resources to the terminal. As another example, the second mode refers to a resource allocation mode in which a terminal selects a radio resource used to perform sidelink communication from within a radio resource pool. That is, the second mode refers to a resource allocation mode in which the terminal selects a specific radio resource as a sidelink radio resource according to a preset condition within a radio resource pool preset in the terminal.

Meanwhile, the simultaneous use mode configuration information may be received through system information. Alternatively, the simultaneous use mode configuration information may be received through higher layer signaling (RRC message). When the simultaneous use mode configuration information is received through system information, the terminal may initiate an RRC connection setup procedure with the base station when the simultaneous use mode configuration information is received.

The simultaneous use mode configuration information may include information for configuring each of one or more sidelink logical channels or sidelink logical channel groups in association with any one of the first mode and the second mode. For example, a specific sidelink logical channel or sidelink logical channel group is configured in association with the first mode, and other sidelink logical channels or sidelink logical channel groups are configured in conjunction with the second mode. It can be included in the usage mode configuration information. This means information for classifying a resource allocation mode for each logical channel or logical channel group.

In addition, the simultaneous use mode configuration information may include information for configuring different radio resource allocation modes for each destination, for each service QoS, for each sidelink communication method, and for each carrier.

An example in which the terminal configures the simultaneous use mode by classifying the radio resource allocation mode according to various criteria will be described in detail by subdividing the embodiments below.

The terminal may perform a step of performing sidelink communication with another terminal by using the allocated radio resource by simultaneously using the first mode and the second mode based on the simultaneous use mode configuration information (S1210).

For example, when the simultaneous use mode configuration information is received and the simultaneous use mode is configured, the terminal may perform radio resource allocation for performing sidelink communication according to the configured mode. For example, when sidelink communication configured in the first mode is requested, the terminal requests sidelink radio resource allocation to the base station, and performs sidelink communication using radio resources scheduled and allocated by the base station. As another example, when sidelink communication configured in the second mode is requested, the terminal performs sidelink communication using a radio resource selected according to a preset condition in the sidelink radio resource pool.

Further, the terminal performs a logical channel priority procedure only for one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode. In contrast, the terminal may not perform a logical channel priority procedure for one or more sidelink logical channels or sidelink logical channel groups configured in association with the second mode.

A procedure for performing sidelink communication according to each mode will be described in more detail with reference to FIG. 13.

13 is a diagram for describing a terminal operation according to another embodiment.

Referring to FIG. 13, the terminal may perform a step of transmitting buffer status information for data to be transmitted to the base station through a sidelink when the simultaneous use mode is configured in the terminal based on the simultaneous use mode configuration information (S1320). .

For example, the buffer status information may include only buffer information of one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode by the simultaneous use mode configuration information. Here, the sidelink logical channel or the sidelink logical channel group is for example, and the buffer status information is based on specific criteria such as each destination of sidelink communication, each service QoS, each sidelink communication method, and each carrier to be described later. It may include only buffer information of sidelink communication linked to the mode.

The terminal may perform the step of receiving the allocated radio resource information based on the buffer status information (S1330). For example, the base station receiving the buffer status information associated with the first mode may transmit radio resource allocation information scheduled based on the buffer status information to the terminal. The terminal receives radio resource information transmitted from the base station and uses it to perform sidelink communication.

As described above, in the case of sidelink communication data configured in connection with the second mode, the sidelink communication may be performed through the radio resource selected by the terminal in the radio resource pool according to preset criteria and conditions.

On the other hand, if it is determined that the simultaneous use mode configuration information is included in the system information before the step of performing sidelink communication, the terminal may perform a step of triggering an RRC connection setup procedure with the base station (S1310).

That is, when the system information includes the simultaneous use mode configuration information and is received, the UE may initiate an RRC connection setup procedure for RRC connection with the base station. For the RRC connection setup procedure, a known RRC procedure may be used, and a detailed description thereof will be omitted.

Through the above operation, the terminal may receive the simultaneous use mode configuration information, and perform sidelink communication through different types of radio resource allocation operations according to sidelink communication data configured in association with each resource allocation mode.

Meanwhile, a base station operation corresponding to a terminal operation will be described with reference to FIG. 14.

14 is a diagram for describing an operation of a base station according to an embodiment.

Referring to FIG. 14, the base station controlling sidelink communication performs a step of transmitting configuration information of the simultaneous use mode to the terminal for configuring the first mode and the second mode, which are different radio resource allocation schemes, to be used simultaneously. Can be (S1400).

For example, the simultaneous use mode configuration information includes configuration information for configuring a terminal to simultaneously use different sidelink resource allocation modes. As an example, the first mode refers to a resource allocation mode in which radio resources used to perform sidelink communication are allocated from a base station. That is, the first mode refers to a resource allocation mode in which the base station dynamically requests sidelink resource allocation and allocates resources to the terminal. As another example, the second mode refers to a resource allocation mode in which a terminal selects a radio resource used to perform sidelink communication from within a radio resource pool. That is, the second mode refers to a resource allocation mode in which the terminal selects a specific radio resource as a sidelink radio resource according to a preset condition within a radio resource pool preset in the terminal.

Meanwhile, the simultaneous use mode configuration information may be transmitted through system information. Alternatively, the simultaneous use mode configuration information may be transmitted through higher layer signaling (RRC message). When the simultaneous use mode configuration information is received through system information, the terminal may initiate an RRC connection setup procedure with the base station when the simultaneous use mode configuration information is received.

The simultaneous use mode configuration information may include information for configuring each of one or more sidelink logical channels or sidelink logical channel groups in association with any one of the first mode and the second mode. For example, a specific sidelink logical channel or sidelink logical channel group is configured in association with the first mode, and other sidelink logical channels or sidelink logical channel groups are configured in conjunction with the second mode. It can be included in the usage mode configuration information. This means information for classifying a resource allocation mode for each logical channel or logical channel group. In addition, the simultaneous use mode configuration information may include information for configuring different radio resource allocation modes for each destination, for each service QoS, for each sidelink communication method, and for each carrier.

When the simultaneous use mode configuration information is received and the simultaneous use mode is configured, the terminal may perform radio resource allocation for performing sidelink communication according to the configured mode. For example, when sidelink communication configured in the first mode is requested, the terminal requests sidelink radio resource allocation to the base station, and performs sidelink communication using radio resources scheduled and allocated by the base station. As another example, when sidelink communication configured in the second mode is requested, the terminal performs sidelink communication using a radio resource selected according to a preset condition in the sidelink radio resource pool.

The base station may perform the step of receiving buffer status information for sidelink communication from the terminal (S1410).

When the terminal configures the simultaneous use mode configuration information, the terminal transmits the buffer status information to the base station when there is data to be transmitted through sidelink communication. The base station receives the buffer status information transmitted by the terminal.

For example, the buffer status information may include only buffer information of one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode by the simultaneous use mode configuration information. Here, the sidelink logical channel or the sidelink logical channel group is for example, and the buffer status information is based on specific criteria such as each destination of sidelink communication, each service QoS, each sidelink communication method, and each carrier to be described later. It may include only buffer information of sidelink communication linked to the mode.

The base station may perform the step of transmitting radio resource information for sidelink communication to the terminal based on the buffer status information (S1420).

For example, the base station receiving the buffer status information associated with the first mode may transmit radio resource allocation information scheduled based on the buffer status information to the terminal. The terminal receives radio resource information transmitted from the base station and uses it to perform sidelink communication. In the case of the sidelink communication data configured in connection with the second mode, the sidelink communication may be performed through the radio resource selected by the terminal in the radio resource pool according to preset criteria and conditions.

Meanwhile, when the system information includes the simultaneous use mode configuration information and is received, the UE may initiate an RRC connection setup procedure for RRC connection with the base station. For the RRC connection setup procedure, a known RRC procedure may be used, and a detailed description thereof will be omitted.

Further, the terminal performs a logical channel priority procedure only for one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode. In contrast, the terminal may not perform a logical channel priority procedure for one or more sidelink logical channels or sidelink logical channel groups configured in association with the second mode.

As described above, the base station transmits the simultaneous use mode configuration information, and the terminal can perform sidelink communication through different radio resource allocation operations according to the sidelink communication data configured in connection with each resource allocation mode. have.

Hereinafter, the configuration of the above-described simultaneous use mode and more detailed operations after the configuration will be described. The embodiments below may be performed individually or through any combination. Meanwhile, the term “simultaneous use” in the present specification means performing sidelink communication using radio resources allocated by a plurality of resource allocation modes within a specific time period. Here, the time section may be a time section division unit in the wireless communication field such as a subframe, a slot, and a symbol.

When using the first mode and the second mode simultaneously

The first mode in which resources for sidelink communication are scheduled by the base station can be used for efficient resource allocation in which the base station does not collide at the request of the terminal. On the other hand, the second mode, in which the terminal autonomously selects resources within the resource pool, can be used even when out of coverage of the base station (Out of coverage), and resource allocation efficiency is improved by allowing resource selection/reselection through resource sensing results. You can increase it. However, as described above, in the prior art, the terminal could operate in only one resource allocation mode at a time. Since the conventional sidelink communication was aimed at providing basic V2X services, it may be efficient to operate in one mode. However, in order to provide various improved V2X communication services, it may be desirable for the terminal to simultaneously support the first mode and the second mode. In this case, the terminal may perform sidelink communication by simultaneously using the first mode and the second mode as follows.

For example, in performing inter-group communication through a small group such as platuning, a specific terminal in the group may share a set of resources among its members in a static manner. For example, the head terminal may request the base station to configure the entire resource pool for the group communication. Alternatively, the head terminal may transmit the entire resource pool configuration for the group communication allocated from the base station to the terminal in the group. Alternatively, the head terminal may transmit the selected configuration of the entire resource pool for the group communication to the terminal in the group. Through this, the terminal in the group can perform groupcast-based sidelink communication through the second mode. At the same time, any individual terminal in the group may wish to perform sidelink communication with another individual terminal in a unicast manner. The corresponding terminal may request resource allocation from the base station to perform groupcast type sidelink communication through the second mode and at the same time perform sidelink communication based on the first mode. As described above, sidelink communication may be performed through the first mode and the second mode at the same time by linking the first mode and the second mode to a communication method (unicast, groupcast, broadcast).

As another example, the first mode and the second mode may be used at the same time for V2X service traffic transmission supporting different QoS requirements. In one carrier or in carriers (eg NR V2X carriers) using the same radio access technology (RAT), for traffic mapped to a logical channel/logical channel group having different QoS requirements The first mode and the second mode may be classified and linked to use the first mode and the second mode at the same time. For example, for a logical channel requiring a low QoS service, sidelink communication may be performed using a second mode through a common resource pool. On the other hand, a first mode may be used for a logical channel requiring a high QoS service. Can be used to perform sidelink communication. As described above, by linking the first mode and the second mode to the logical channel/logical channel group, sidelink communication can be provided through the first mode and the second mode at the same time. In this case, the mapping between the logical channel/logical channel group and the priority may be configured by the base station in the terminal through RRC signaling. Alternatively, the source terminal may be configured in the destination terminal through RRC signaling or higher layer (V2X control function or V2X application or PC5 layer) signaling. Alternatively, the mapping between the logical channel/logical channel group and the priority is configured by the head terminal in the source terminal and/or the destination terminal through RRC signaling or higher layer (V2X control function or V2X application or PC5 layer) signaling, or the V2X application server It may be configured in the source terminal and/or the destination terminal through higher layer (V2X control function or V2X application or PC5 layer) signaling. Alternatively, an upper layer (V2X control function or V2X application or PC5 layer) may be indicated as a lower layer (RRC or MAC) of the terminal, or may be preconfigured in each terminal.

As another example, the first mode and the second mode may be used simultaneously through different carriers. Two non-overlapping carrier sets may be configured per destination in the terminal by the base station (or by pre-configuration). In this specification, a destination means a destination to which sidelink data is to be received. Therefore, the destination is Prose UE ID, destination ID included in Sidelink Control Information, L2 destination ID, destination index, L2 group ID, L2 broadcast ID, destination address, group address, broadcast address, identification information allocated from the upper layer, V2X In a service/application, information for identifying a destination terminal may be replaced with any information that may be used to identify a destination to which sidelink data should be received. This can be used in the form of a bitstring, URI, IP address, etc., and some information of any existing identification information can be used or any existing identification information can be modified and used.

Meanwhile, for example, sidelink communication may be performed on a carrier set associated with a specific destination through the first mode. Sidelink communication may be performed on a carrier set associated with another specific destination through the second mode. The above-described destination information may be reported by the terminal to the base station. For another example, one carrier set may be associated with a specific logical channel/logical channel group. In addition, another carrier set may be associated with another specific logical channel/logical channel group. V2X communication may be performed through the first mode for a carrier set associated with a specific logical channel/logical channel group. Sidelink communication may be performed on a carrier set associated with another specific logical channel/logical channel group through the second mode. In this way, sidelink communication can be provided through the first mode and the second mode simultaneously by linking the first mode and the second mode to the carrier. At this time, the destination information and the logical channel/logical channel group information may be independently configured and used. Alternatively, one or more logical channels (LCID)/logical channel groups (LCGID) may be associated with each other according to a service traffic type for one destination. The linkage between the destination and the logical channel/logical channel group can be configured by the base station to the terminal through RRC signaling. Alternatively, the source terminal may be configured in the destination terminal through RRC signaling or higher layer (V2X control function or V2X application or PC5 layer) signaling. Or, the head terminal is configured in the source terminal and/or the destination terminal through RRC signaling or higher layer (V2X control function or V2X application or PC5 layer) signaling, or the V2X application server is an upper layer (V2X control function or V2X application or PC5 layer) ) It can be configured in the source terminal and/or the destination terminal through signaling. Alternatively, an upper layer (V2X control function or V2X application or PC5 layer) may be indicated as a lower layer (RRC or MAC) of the terminal, or may be preconfigured in the terminal.

As another example, the first mode and the second mode may be used simultaneously through different RATs. Different RATs for each destination may be linked and configured to the terminal by the base station (or by pre-configuration). For example, an LTE/LTE carrier set may be associated with a specific destination, and an NR/NR carrier set may be associated with another specific destination. In addition, sidelink communication may be performed with respect to a destination linked to the LTE/LTE carrier set through the first mode. Sidelink communication may be performed with respect to a destination linked to the NR/NR carrier set through the second mode. The above-described destination information may be reported by the terminal to the base station. For another example, a specific logical channel/logical channel group may be linked to an LTE/LTE carrier set. Further, another specific logical channel/logical channel group can be linked to the NR/NR carrier set. Sidelink communication may be performed through the first mode for service traffic of a specific logical channel/logical channel group linked to an LTE/LTE carrier. Sidelink communication may be performed through the second mode for service traffic of another specific logical channel/logical channel group linked to the NR/NR carrier. As another example, the terminal may establish an RRC connection to the NR base station, and perform sidelink communication based on the first mode by the NR base station for a specific destination or a specific logical channel. At the same time, the NR base station may perform sidelink communication based on the second mode by another specific destination or a specific logical channel or by pre-configuration. In this way, the first mode and the second mode may be linked to the RAT, and sidelink communication may be provided through the first mode and the second mode at the same time. In this case, the destination information and the logical channel information may be independently configured and used. Alternatively, one or more logical channels (LCIDs) may be linked to one destination according to a service traffic type. The linkage between the destination and the RAT or between the logical channel and the RAT can be configured by the base station to the terminal through RRC signaling. Alternatively, the source terminal may be configured in the destination terminal through RRC signaling or higher layer (V2X control function or V2X application or PC5 layer) signaling. Or, the head terminal is configured in the source terminal and/or the destination terminal through RRC signaling or higher layer (V2X control function or V2X application or PC5 layer) signaling, or the V2X application server is an upper layer (V2X control function or V2X application or PC5 layer) ) It can be configured in the source terminal and/or the destination terminal through signaling. Alternatively, an upper layer (V2X control function or V2X application or PC5 layer) may be indicated as a lower layer (RRC or MAC) of the terminal, or may be preconfigured in the terminal.

In this way, the terminal can simultaneously perform sidelink communication by dividing the first mode and the second mode through various linked operations. As an example, it has been described that the various information described above and the first mode-only information and the second mode-only information described below are received through an RRC message, but may be received through system information. In addition, information associated with the aforementioned various criteria and information received from a base station to be described later may be included in the above-described simultaneous use mode configuration information.

Hereinafter, a specific embodiment of performing sidelink communication by simultaneously configuring a first mode and a second mode in one terminal will be described.

First mode only (mode 1 only) / definition of preference information and related terminal operation

Information indicating whether the first mode is dedicated/preferred may be defined for each logical channel/logical channel group, for each destination, or for each logical channel/logical channel group associated with one destination. Alternatively, information for indicating a default resource allocation mode for sidelink communication may be defined to be cell-specific through system information or terminal-specifically through a dedicated RRC message. When the default resource allocation mode is configured as the second mode, the base station determines whether the first mode is dedicated/preferred in a logical channel/logical channel group specific or destination specific or logical channel/logical channel group associated with one destination. I can instruct. As described above, the logical channel/logical channel group/destination may be associated with a carrier. Alternatively, the logical channel/logical channel group/destination may be linked to the RAT. Accordingly, whether or not the first mode is dedicated/preferred may be indicated by specific carrier or specific RAT.

As an example, the base station may be configured to perform sidelink communication with a second mode as a default for an RRC connected state terminal within coverage. To this end, the base station may configure a resource pool (eg v2x-CommTxPoolNormalDedicated or v2x-CommTxPoolNormal or p2x-CommTxPoolNormal in the entry of v2x-InterFreqInfoList for the concerned frequency in sl-V2X-ConfigDedicated in RRC Reconfiguration) for this purpose. . At the same time, the base station may instruct the corresponding terminal to operate in the first mode for a specific logical channel/logical channel group/destination. The terminal may be configured to request allocation of transmission resources for sidelink communication to the base station for the logical channel/logical channel group/destination indicated in the lower layer. The terminal may perform sidelink communication through the second mode configured as default except for the logical channel/logical channel group/destination instructed to operate in the first mode.

As another example, the base station may instruct the RRC connected state terminal within coverage to operate in the second mode for a specific logical channel/logical channel group/destination. To this end, the base station can be configured by linking a resource pool for sidelink communication and a logical channel/logical channel group/destination using the resource pool. The terminal is configured to transmit sidelink control information and corresponding data to the lower layer by using the resource pool indicated by the base station for the logical channel/logical channel group/destination. At the same time, the base station may instruct the corresponding terminal to operate in the first mode for another specific logical channel/logical channel group/destination. The terminal is configured to request allocation of transmission resources for sidelink communication to the base station for the logical channel/logical channel group/destination indicated in the lower layer.

As another example, when the terminal is out of coverage, the terminal may operate in the second mode. For this, a resource pool may be preconfigured in the terminal. To this end, as described above, pre-configuration parameters are provided to the terminal by the upper layer. The preconfiguration parameter is utilized as preconfiguration (SL-Preconfiguration/SL-V2X-Preconfiguration) information in RRC, so that the UE can operate in the second mode. The preconfiguration (SL-Preconfiguration/SL-V2X-Preconfiguration) information is a first mode specific to a terminal-specific or logical channel/logical channel group-specific or destination-specific or logical channel/logical channel group associated with one destination. It may include information indicating whether or not exclusive/preferred. When the terminal storing the pre-configuration information is out of coverage, the terminal can perform sidelink communication according to the pre-configuration. When the terminal enters the coverage (or when the terminal detects a cell that provides sidelink configuration), the terminal establishes/sets up an RRC connection for sidelink communication for the corresponding logical channel/logical channel group/destination (eg RRC establish/RRC setup) procedure can be started. For example, when the terminal is performing sidelink communication for a corresponding logical channel/logical channel group/destination in the RRC idle mode or triggered, RRC connection establishment/setup may be initiated. Another example is that the UE detects a cell or a V2X frequency cell that broadcasts information on a first mode only/preferred through system information, and a corresponding logical channel/logical channel group/destination in the RRC idle mode. RRC connection establishment may be initiated when the for sidelink communication is being performed or triggered. As another example, when the default resource allocation mode of the terminal is configured as the first mode, or when the base station indicates the default resource allocation mode as the first mode through system information, the RRC idle mode terminal detects the corresponding cell or RRC connection establishment may be initiated when sidelink communication for a logical channel/logical channel group/destination is being performed or triggered.

Mode 2 only / definition of preference information and related terminal operation

Information indicating whether the second mode is dedicated/preferred may be defined for each logical channel/logical channel group, for each destination, or for each logical channel/logical channel group associated with one destination. Alternatively, information for indicating a default resource allocation mode for sidelink communication may be defined to be cell-specific through system information or terminal-specifically through a dedicated RRC message. When the default resource allocation mode is configured as the first mode, the base station determines whether the second mode is dedicated/preferred in a logical channel/logical channel group-specific or a destination-specific or a logical channel/logical channel group associated with one destination. I can instruct. As described above, the logical channel/logical channel group/destination may be associated with a carrier. Alternatively, the logical channel/logical channel group/destination may be linked to the RAT. Accordingly, whether or not the second mode is dedicated/preferred may be indicated by specific carrier or specific RAT.

As an example, the base station may be configured to perform sidelink communication by defaulting to the first mode for an RRC connected state terminal within coverage. At the same time, the base station may instruct the corresponding terminal to operate in the second mode for a specific logical channel/logical channel group/destination. The base station may configure a resource pool for sidelink communication in association with a logical channel/logical channel group/destination using the resource pool. The terminal is configured to transmit sidelink control information and corresponding data to the lower layer by using a resource pool indicated by the base station for the corresponding logical channel/logical channel group/destination. The terminal may perform sidelink communication through the first mode configured as default except for the logical channel/logical channel group/destination instructed to operate in the second mode. The terminal is configured to request transmission resource allocation for sidelink communication to the base station except for the logical channel/logical channel group/destination instructed to operate in the second mode to the lower layer. When a sidelink buffer status report trigger condition occurs and the terminal transmits the sidelink buffer status information (BSR) to the base station, the sidelink BSR is for transmission except for the logical channel group instructed to operate in the second mode. It may contain buffer status information for all logical channel groups (LCGs) with available data. In the prior art, for example, for a regular and periodic sidelink BSR, if the number of bits in the uplink grant (or SCI) is a buffer state for all LCGs having data available for transmission and the sidelink BSR including the subheader If it is greater than or equal to the size of, it reported a sidelink BSR containing the buffer status for all logical channel groups (LCGs) with data available for transmission. However, for the logical channel group operating in the second mode, it is not necessary to report the BSR to the base station, so even if there is data in the L2 buffer for the corresponding logical channel group, there is no need to report it. This can also be applied to the padded sidelink BSR. In addition, there is no need to trigger the BSR for the logical channel group operating in the second mode. Accordingly, the terminal can be configured to detect the BSR trigger condition except for the logical channel group operating in the second mode. For example, for one sidelink logical channel to one destination, SL data in the RLC entity or PDCP entity is made available for transmission. And while belonging to the same destination and belonging to one sidelink logical channel having a higher priority than the priority of a sidelink logical channel belonging to any LCG for which data is already available for transmission, the sidelink logical channel is the second Regular sidelink BSR if there is no data available for current transmission for any of the sidelink logical channels operating in the second mode among the sidelink logical channels that operate in the same destination mode, or This can be triggered. In addition, the logical channel priority (LCP) procedure can be performed for the logical channel priority procedure except for the logical channel operating in the second mode. For example, LCP may be performed only for a logical channel operating in the first mode except for a logical channel configured in the second mode. For another example, LCP may be performed only for a logical channel operating in the first mode except for a logical channel associated with a carrier configured in the second mode. For another example, LCP may be performed only on a logical channel operating in the first mode except for a logical channel associated with the RAT configured in the second mode. For another example, the second mode resource pool may be specifically linked and indicated by a logical channel/logical channel group/destination/carrier/RAT. This may be included in the above-described simultaneous use mode configuration information.

Definition of a logical channel supporting both the first mode and the second mode and related terminal operation

For example, it may be configured to support both the first mode and the second mode at an arbitrary point in time (or at the same time) for each logical channel/logical channel group, each destination, or each logical channel/logical channel group linked to one destination. In this case, for example, the terminal may perform sidelink communication in the same manner as the existing procedure according to the first mode. The UE can trigger the BSR if there is data available for transmission in the corresponding logical channel. Also, when a new transmission is performed, the terminal may perform an LCP procedure for a corresponding logical channel. The UE requests scheduling from the base station until it receives sidelink control information (SCI) or even when SCI is received, the received SCI and exclusive radio resources (e.g., by dividing RAT/carrier/frequency/time) Through the second mode, sidelink communication may be performed. Data received through different radio resources may be aggregated in MAC, PDCP, or higher layers. A merge entity (ex, MAC or PDCP or higher layer) that merges data may perform flow control and/or reordering. At this time, if the terminal has processed all available data for transmission in the second mode, the base station does not need to continue allocating resources for the corresponding logical channel through the first mode. Therefore, when the terminal transmits all available data for transmission in the second mode (for example, if the corresponding data does not exist in the L2 buffer), the terminal can indicate this situation to the base station. Specifically, indication of this situation may be performed using either MAC CE or UCI/PUSCH or RRC signaling. In addition, signaling for indicating this situation may include corresponding logical channel/logical channel group identification information. For another example, the terminal may perform sidelink communication except for a logical channel supporting both the first mode and the second mode in some existing procedures (eg, BSR procedure) according to the first mode. For example, when the terminal transmits the sidelink BSR to the base station according to the satisfaction of the sidelink buffer status report trigger condition, the corresponding sidelink BSR performs transmission except for a logical channel group supporting both the first mode and the second mode. It may contain buffer states for all logical channel groups (LCGs) with data available for use. As another example, the sidelink BSR includes a logical channel group supporting both the first mode and the second mode, and the sidelink includes buffer status for all logical channel groups (LCGs) having data available for transmission. You can also have a BSR report. Since the base station already knows that the corresponding logical channel of the terminal supports both the first mode and the second mode, it can efficiently perform scheduling in consideration of this.

As another example, the base station must be configured to operate in only one of the first mode and the second mode at an arbitrary point in time for each logical channel/logical channel group or destination, or for each logical channel/logical channel group linked to one destination. I can. Through this, any logical channel/logical channel group or logical channel/logical channel group linked to an arbitrary destination or an arbitrary destination operates in only one of the first mode and the second mode at an arbitrary point in time to avoid complexity. I can. The logical channel/logical channel group associated with each mode may perform sidelink communication through the above-described embodiment.

Meanwhile, a cell change/handover operation may be performed according to the movement of the terminal. When cell change/handover is performed according to the movement of the terminal, it is preferable that the information on the above-described mode configuration is maintained. For example, when a terminal is handed over from a source cell to a target cell according to a cell change, if sidelink communication is performed by maintaining the configured mode, service interruption can be reduced. To this end, the source base station/source cell provides the mode configuration information for each logical channel/logical channel group or destination or logical channel/logical channel group linked to one destination in the handover preparation message (or handover request message). Including, it can be delivered to the target base station/target cell. The target base station may include information for performing sidelink communication by maintaining a corresponding mode in the handover command message transmitted to the terminal through the source base station. As another example, the base station may broadcast information for instructing to maintain a corresponding mode in the source cell and the target cell through system information. The terminal receiving the information may perform communication by maintaining the corresponding mode during cell change.

As described above, the present disclosure has the effect of enabling effective provision of services for various sidelink services by supporting a single terminal to simultaneously perform sidelink communication using a first mode and a second mode. .

Meanwhile, in the case where the terminal simultaneously performs sidelink communication through two or more resource allocation modes in the above-described manner, the data reliability problem may be more important. In addition, since only RLC UM was supported in TE system-based V2X communication, there was a problem in that it was difficult to support improved V2X service through lossless transmission. have. In this situation, the present disclosure intends to provide a highly reliable sidelink communication technology based on RLC AM. In particular, when an RLC retransmission failure occurs in RLC AM-based sidelink communication, a specific method for solving a problem in which service may be interrupted is proposed.

For example, the method of performing vehicle communication (V2X communication) includes receiving radio bearer configuration information from a base station for configuring a radio bearer on a sidelink interface used for vehicle communication, and radio bearer. Based on the configuration information, the step of configuring a radio bearer using a sidelink interface and an AM RLC entity linked to the radio bearer monitors the number of retransmissions of transmission data through the radio bearer, and whether the number of retransmissions reaches the maximum number of retransmissions. The detecting step and when the number of retransmissions reaches the maximum number of retransmissions may include transmitting sidelink failure information to the base station.

Specifically, a terminal performing vehicle to everything communication (V2X communication) may perform a step of receiving radio bearer configuration information from a base station for configuring a radio bearer on a sidelink interface used for vehicle communication. . The terminal performs vehicle communication through the sidelink interface. Therefore, the terminal needs to configure a radio bearer on the sidelink interface. To this end, the terminal receives radio bearer configuration information for the sidelink from the base station. The radio bearer configuration information may include RLC bearer configuration information. The RLC bearer configuration information may include parameters necessary to configure an AM RLC entity for a sidelink. For example, the RLC bearer configuration information may include uplink AM RLC configuration information and downlink AM RLC configuration information.

The terminal may perform the step of configuring a radio bearer using a sidelink interface based on the radio bearer configuration information. For example, the terminal configures the AM RLC entity for the sidelink in the terminal using the radio bearer configuration information. In addition, the terminal may set a radio bearer configured on the sidelink interface for vehicle communication and link it to the configured AM RLC entity. The radio bearer configured on the sidelink interface may be composed of one or more, and may be configured for each V2X service. The terminal can transmit and receive data with another vehicle communication terminal on the sidelink interface using the configured radio bearer. As described above, data may be transmitted/received by a unicast method, but may be transmitted/received by a groupcast or broadcast method.

The terminal may perform a step of monitoring whether the number of retransmissions of transmission data through the radio bearer is monitored by the AM RLC entity linked to the radio bearer, and detecting whether the number of retransmissions has reached the maximum number of retransmissions. For example, since vehicle communication data is transmitted and received through the AM RLC entity, the terminal receives an acknowledgment message for the transmission data from the receiving terminal. If an acknowledgment message (ex, ACK message) for specific transmission data is not received, the AM RLC entity of the terminal performs a retransmission operation. Therefore, in the conventional LTE system-based vehicle communication, the ARQ process is not applied, but in the vehicle communication of the present disclosure, the ARQ process operation for securing high reliability is applied.

The AM RLC entity of the terminal monitors the number of retransmissions of transmission data transmitted through the sidelink radio bearer. This is because if the transmission data is continuously retransmitted and the number of retransmissions for specific transmission data reaches a preset maximum number of retransmissions, it is necessary to consider a radio link failure. Accordingly, the AM RLC entity of the terminal monitors and determines whether the number of retransmissions of specific transmission data reaches a preset maximum number of retransmissions.

When the number of retransmissions reaches the maximum number of retransmissions, the terminal may perform a step of transmitting sidelink failure information to the base station. When the number of retransmissions for specific transmission data in the AM RLC entity of the terminal reaches a preset maximum number of retransmissions, it is recognized that a problem has occurred in the corresponding sidelink. For example, the terminal may detect a radio link failure of a sidelink through which transmission data is transmitted. In this case, when the base station allocates sidelink radio resources, the terminal needs to request the base station to schedule a new sidelink radio resource. Alternatively, the base station needs to recognize the radio link failure of the sidelink for any reason.

To this end, the terminal may transmit sidelink failure information to the base station when the number of retransmissions for specific transmission data in the AM RLC entity of the terminal reaches a preset maximum number of retransmissions.

For example, the sidelink failure information may include at least one of serving cell identification information, serving cell measurement result information, sidelink carrier identification information, time stamp information, terminal location information, and V2X session identification information. Through this, the base station checks information on a specific cell, carrier, time, location, or session related to the radio link failure situation of the sidelink reported by the terminal. If necessary, the base station may allocate a new sidelink radio resource to the terminal.

As another example, the sidelink failure information may include sidelink RRC failure type information when the terminal is in an RRC connection state. The terminal in the RRC connected state can also transmit and receive data with the base station. Therefore, when the terminal transmits radio link failure information to the base station, it may be difficult for the base station to distinguish whether the corresponding radio link failure is a radio link failure with the base station or a radio link failure to another carrier in a dual connectivity or CA situation. . Therefore, when the terminal is in the RRC connection state, the terminal transmits a message including RRC failure type information to distinguish sidelink failure information, indicating that the sidelink fails due to the excess number of retransmissions in the sidelink (or a specific radio bearer). I can instruct.

Meanwhile, the UE may perform vehicle communication even in an RRC state other than the RRC connected state. That is, in vehicle communication, since data is directly transmitted and received between the transmitting terminal and the receiving terminal regardless of the connection state with the base station, the RRC IDLE state or the RRC Inactive state terminal can also be performed.

Accordingly, when the number of AM RLC retransmissions described above reaches the maximum number of retransmissions, even in the RRC IDLE state or the RRC Inactive state, it is necessary to report sidelink failure information to the base station.

For example, the sidelink failure information may be transmitted to the base station through the RRC connection establishment procedure of the terminal when the terminal is in the RRC idle state or the RRC Inactive state.

For example, when the terminal is in the RRC idle state, the sidelink failure information may be transmitted to the base station during the process of the terminal establishing an RRC connection with the base station or after the RRC connection is established. If sidelink failure information is transmitted during the RRC connection setup process, it may be included in an RRC setup request message and an RRC setup completion message transmitted from the terminal to the base station.

As another example, when the terminal is in the RRC Inactive state, the sidelink failure information may be transmitted to the base station during the RRC connection resumption process for the terminal to transition to the RRC connection state or after RRC connection is established. If sidelink failure information is transmitted during the RRC connection setup process, it may be included in an RRC resumption request message and an RRC resumption complete message transmitted from the terminal to the base station.

Through this operation, the terminal can perform the operation of transmitting and receiving sidelink data based on the AM RLC entity without ambiguity, thereby supporting vehicle communication based on high reliability. This can be applied to both the first mode and the second mode described above. Alternatively, it may be applied only in the case of a logical channel/logical channel group/destination/RAT set as the first mode. Alternatively, it may be applied only in the case of a logical channel/logical channel group/destination/RAT set as the second mode.

Hereinafter, a terminal and a base station device capable of performing some or all of the operations of the terminal and the base station according to the present disclosure described above will be briefly described with reference to the drawings.

15 is a diagram illustrating a configuration of a terminal according to an embodiment.

Referring to FIG. 15, a terminal 1500 for performing sidelink communication is a receiving unit that receives configuration information from a base station for simultaneous use mode configuration to simultaneously use a first mode and a second mode, which are different radio resource allocation schemes. 1530 and the control unit 1510 for controlling sidelink communication with other terminals using radio resources allocated by simultaneously using the first mode and the second mode based on the simultaneous use mode configuration information.

For example, the simultaneous use mode configuration information includes configuration information for configuring a terminal to simultaneously use different sidelink resource allocation modes. As an example, the first mode refers to a resource allocation mode in which radio resources used to perform sidelink communication are allocated from a base station. As another example, the second mode refers to a resource allocation mode in which a terminal selects a radio resource used to perform sidelink communication from within a radio resource pool.

Meanwhile, the simultaneous use mode configuration information may be received through system information. Alternatively, the simultaneous use mode configuration information may be received through higher layer signaling (RRC message). When the simultaneous use mode configuration information is received through the system information, the controller 1510 may initiate an RRC connection setup procedure with the base station when the simultaneous use mode configuration information is received.

The simultaneous use mode configuration information may include information for configuring each of one or more sidelink logical channels or sidelink logical channel groups in association with any one of the first mode and the second mode. For example, a specific sidelink logical channel or sidelink logical channel group is configured in association with the first mode, and other sidelink logical channels or sidelink logical channel groups are configured in conjunction with the second mode. It can be included in the usage mode configuration information. This means information for classifying a resource allocation mode for each logical channel or logical channel group.

In addition, the simultaneous use mode configuration information may include information for configuring different radio resource allocation modes for each destination, service QoS, sidelink communication method, and carrier of the aforementioned sidelink communication.

Meanwhile, when the simultaneous use mode configuration information is received and the simultaneous use mode is configured, the control unit 1510 may perform radio resource allocation for performing sidelink communication according to the configured mode. For example, when a sidelink communication configured in the first mode is requested, the transmission unit 1520 requests sidelink radio resource allocation to the base station, and the control unit 1510 uses the radio resource scheduled and allocated by the base station. Link communication is performed. As another example, when a sidelink communication configured in the second mode is requested, the controller 1510 performs sidelink communication using a radio resource selected according to a preset condition in the sidelink radio resource pool.

In addition, the controller 1510 performs a logical channel priority procedure only for one or more sidelink logical channels or sidelink logical channel groups configured in connection with the first mode. Alternatively, the controller 1510 may not perform a logical channel priority procedure for one or more sidelink logical channels or sidelink logical channel groups configured in connection with the second mode.

Meanwhile, the transmitter 1520 may transmit buffer status information for data to be transmitted to the base station through a sidelink when the simultaneous use mode is configured in the terminal based on the simultaneous use mode configuration information.

For example, the buffer status information may include only buffer information of one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode by the simultaneous use mode configuration information. Here, the sidelink logical channel or the sidelink logical channel group is for example, and the buffer status information is first based on specific criteria such as the above-described sidelink communication destination, service QoS, sidelink communication method, and carrier. It may include only buffer information of sidelink communication linked to the mode.

The receiver 1530 may receive radio resource information allocated based on the buffer status information. For example, the base station receiving the buffer status information associated with the first mode may transmit radio resource allocation information scheduled based on the buffer status information to the terminal 1500. The receiving unit 1530 receives radio resource information transmitted from the base station, and the control unit 1510 uses it to perform sidelink communication.

As described above, in the case of sidelink communication data configured in association with the second mode, the controller 1510 may perform sidelink communication through a radio resource selected according to preset criteria and conditions within the radio resource pool.

Meanwhile, if it is determined that the simultaneous use mode configuration information is included in the system information before the step of performing the sidelink communication, the controller 1510 may trigger an RRC connection setup procedure with the base station. That is, when the system information includes the simultaneous use mode configuration information and is received, the controller 1510 may initiate an RRC connection setup procedure for RRC connection with the base station.

In addition, the controller 1510 controls the overall operation of the terminal 1500 according to sidelink communication according to a plurality of different resource allocation modes required to perform the above-described embodiments.

In addition, the transmission unit 1520 and the reception unit 1530 are used to transmit and receive signals, messages, and data necessary for performing the above-described embodiments with a base station, other terminals, and each entity on the V2X architecture.

16 is a diagram for describing a configuration of a base station according to an embodiment.

Referring to FIG. 16, a base station 1600 for controlling sidelink communication is a transmitter for transmitting configuration information of a simultaneous use mode to a terminal for configuring the first mode and the second mode, which are different radio resource allocation schemes, to be used simultaneously. And a receiving unit 1630 for receiving buffer status information for sidelink communication from the terminal 1620 and the transmitting unit 1620 transmits radio resource information for sidelink communication to the terminal based on the buffer status information, The terminal simultaneously uses the first mode and the second mode based on the simultaneous use mode configuration information, and performs sidelink communication with another terminal using the allocated radio resource.

For example, the simultaneous use mode configuration information includes configuration information for configuring a terminal to simultaneously use different sidelink resource allocation modes. As an example, the first mode refers to a resource allocation mode in which radio resources used to perform sidelink communication are allocated from a base station. As another example, the second mode refers to a resource allocation mode in which a terminal selects a radio resource used to perform sidelink communication from within a radio resource pool.

Meanwhile, the simultaneous use mode configuration information may be transmitted through system information. Alternatively, the simultaneous use mode configuration information may be transmitted through higher layer signaling (RRC message). When the simultaneous use mode configuration information is received through system information, the terminal may initiate an RRC connection setup procedure with the base station when the simultaneous use mode configuration information is received.

The simultaneous use mode configuration information may include information for configuring each of one or more sidelink logical channels or sidelink logical channel groups in association with any one of the first mode and the second mode. For example, a specific sidelink logical channel or sidelink logical channel group is configured in association with the first mode, and other sidelink logical channels or sidelink logical channel groups are configured in conjunction with the second mode. It can be included in the usage mode configuration information. This means information for classifying a resource allocation mode for each logical channel or logical channel group. In addition, the simultaneous use mode configuration information may include information for configuring different radio resource allocation modes for each destination, for each service QoS, for each sidelink communication method, and for each carrier.

When the simultaneous use mode configuration information is received and the simultaneous use mode is configured, the terminal may perform radio resource allocation for performing sidelink communication according to the configured mode. For example, when sidelink communication configured in the first mode is requested, the terminal requests sidelink radio resource allocation to the base station, and performs sidelink communication using radio resources scheduled and allocated by the base station. As another example, when sidelink communication configured in the second mode is requested, the terminal performs sidelink communication using a radio resource selected according to a preset condition in the sidelink radio resource pool.

When the terminal configures the simultaneous use mode configuration information, the terminal transmits the buffer status information to the base station when there is data to be transmitted through sidelink communication. The receiving unit 1630 receives buffer status information transmitted by the terminal.

For example, the buffer status information may include only buffer information of one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode by the simultaneous use mode configuration information. Here, the sidelink logical channel or the sidelink logical channel group is for example, and the buffer status information is first based on specific criteria such as the above-described sidelink communication destination, service QoS, sidelink communication method, and carrier. It may include only buffer information of sidelink communication linked to the mode.

Meanwhile, the transmitter 1620 of the base station 1600 that has received the buffer status information associated with the first mode may transmit radio resource allocation information scheduled based on the buffer status information to the terminal. The terminal receives radio resource information transmitted from the base station and uses it to perform sidelink communication. In the case of the sidelink communication data configured in connection with the second mode, the sidelink communication may be performed through the radio resource selected by the terminal in the radio resource pool according to preset criteria and conditions.

Meanwhile, when the system information includes the simultaneous use mode configuration information and is received, the UE may initiate an RRC connection setup procedure for RRC connection with the base station. Further, the terminal performs a logical channel priority procedure only for one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode. In contrast, the terminal may not perform a logical channel priority procedure for one or more sidelink logical channels or sidelink logical channel groups configured in association with the second mode.

In addition, the controller 1610 controls the overall operation of the base station 1600 according to controlling the sidelink communication performance of the terminal according to a plurality of different resource allocation modes required to perform the above-described embodiments. .

In addition, the transmitting unit 1620 and the receiving unit 1630 are used to transmit and receive signals, messages, and data necessary for performing the above-described embodiments with other base stations, other terminals, and each entity on the V2X architecture.

The above-described embodiments may be supported by standard documents disclosed in at least one of IEEE 802, 3GPP and 3GPP2 wireless access systems. That is, steps, configurations, and parts not described in order to clearly reveal the present technical idea among the embodiments may be supported by the aforementioned standard documents. In addition, all terms disclosed in the present specification can be described by the standard documents disclosed above.

The above-described embodiments can be implemented through various means. For example, the present embodiments may be implemented by hardware, firmware, software, or a combination thereof.

In the case of implementation by hardware, the method according to the embodiments includes one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), and FPGAs. (Field Programmable Gate Arrays), can be implemented by a processor, a controller, a microcontroller, a microprocessor.

In the case of implementation by firmware or software, the method according to the embodiments may be implemented in the form of an apparatus, procedure, or function that performs the functions or operations described above. The software code may be stored in a memory unit and driven by a processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor through various known means.

In addition, terms such as "system", "processor", "controller", "component", "module", "interface", "model", and "unit" described above are generally used in terms of computer-related entity hardware, hardware and software. It can mean a combination, software, or running software. For example, the above-described components may be, but are not limited to, a process driven by a processor, a processor, a controller, a control processor, an object, an execution thread, a program, and/or a computer. For example, components can be both a controller or processor and an application running on a controller or processor. One or more components can reside within a process and/or thread of execution, and components can reside on one machine or be deployed on more than one machine.

The description above and the accompanying drawings are merely illustrative of the spirit of the present technology, and those of ordinary skill in the art can combine, separate, replace, and use configurations within a range not departing from the essential characteristics of the present technology. Various modifications and variations such as changes will be possible. Accordingly, the embodiments disclosed in the present specification are not intended to limit the present technical idea, but to describe it, and the scope of the present technical idea is not limited by these embodiments. The scope of protection of the present technical idea should be interpreted by the claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present specification.

Claims (24)

In the method for the terminal to perform sidelink communication,
Receiving, from the base station, concurrent use mode configuration information for configuring to use the first mode and the second mode, which are different radio resource allocation schemes, at the same time; And
And performing sidelink communication with another terminal using radio resources allocated by simultaneously using the first mode and the second mode based on the simultaneous use mode configuration information. The method of claim 1,
The first mode,
It is a resource allocation mode in which radio resources used to perform the sidelink communication are allocated from the base station,
The second mode,
And a resource allocation mode in which the terminal selects a radio resource used for performing the sidelink communication from within a radio resource pool. The method of claim 1,
The above simultaneous use mode configuration information
A method comprising information for configuring each of one or more sidelink logical channels or sidelink logical channel groups in association with any one of the first mode and the second mode. The method of claim 3,
The step of performing the sidelink communication,
Transmitting buffer status information for data to be transmitted through the sidelink to the base station; And
Further comprising the step of receiving radio resource information allocated based on the buffer status information,
The buffer status information,
And only buffer information of the one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode. The method of claim 3,
The step of performing the sidelink communication,
Performing a logical channel priority procedure only for the one or more sidelink logical channels or sidelink logical channel groups configured in connection with the first mode,
And not performing a logical channel priority procedure for the one or more sidelink logical channels or sidelink logical channel groups configured in association with the second mode. The method of claim 1,
Before the step of performing the sidelink communication,
If it is confirmed that the simultaneous use mode configuration information is included in the system information, the method further comprising the step of triggering an RRC connection setup procedure with the base station. In the method for the base station to control sidelink communication,
Transmitting, to the terminal, simultaneous use mode configuration information for configuring the first mode and the second mode, which are different radio resource allocation schemes, to be used simultaneously;
Receiving buffer status information for sidelink communication from the terminal; And
And transmitting radio resource information for the sidelink communication to the terminal based on the buffer status information,
The terminal,
A method of performing sidelink communication with another terminal using radio resources allocated by simultaneously using the first mode and the second mode based on the simultaneous use mode configuration information. The method of claim 7,
The first mode,
It is a resource allocation mode in which the base station allocates radio resources used to perform the sidelink communication,
The second mode,
And a resource allocation mode in which the terminal selects a radio resource used for performing the sidelink communication from within a radio resource pool. The method of claim 7,
The above simultaneous use mode configuration information
A method comprising information for configuring each of one or more sidelink logical channels or sidelink logical channel groups in association with any one of the first mode and the second mode. The method of claim 9,
The buffer status information,
And only buffer information of the one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode. The method of claim 9,
The terminal,
Performing a logical channel priority procedure only for the one or more sidelink logical channels or sidelink logical channel groups configured in connection with the first mode,
And not performing a logical channel priority procedure for the one or more sidelink logical channels or sidelink logical channel groups configured in association with the second mode. The method of claim 7,
The simultaneous use mode configuration information is included in the system information,
The UE, when the simultaneous use mode configuration information is received, triggers an RRC connection setup procedure with the base station. In the terminal performing sidelink communication,
A receiving unit for receiving configuration information from the base station for simultaneous use mode configuration to simultaneously use the first mode and the second mode, which are different radio resource allocation schemes; And
A terminal including a control unit for controlling sidelink communication with another terminal using radio resources allocated by simultaneously using the first mode and the second mode based on the simultaneous use mode configuration information. The method of claim 13,
The first mode,
It is a resource allocation mode in which radio resources used to perform the sidelink communication are allocated from the base station,
The second mode,
The terminal, characterized in that in a resource allocation mode in which the terminal selects a radio resource used to perform the sidelink communication from within a radio resource pool. The method of claim 13,
The above simultaneous use mode configuration information
A terminal including information for configuring each of one or more sidelink logical channels or sidelink logical channel groups in association with any one of the first mode and the second mode. The method of claim 15,
Further comprising a transmitter for transmitting the buffer status information for the data to be transmitted through the sidelink to the base station,
The receiving unit,
Receiving radio resource information allocated based on the buffer status information,
The buffer status information,
And only buffer information of the one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode. The method of claim 15,
The control unit,
Performing a logical channel priority procedure only for the one or more sidelink logical channels or sidelink logical channel groups configured in connection with the first mode,
And a logical channel priority procedure is not performed for the one or more sidelink logical channels or sidelink logical channel groups configured in association with the second mode. The method of claim 13,
The control unit,
When it is confirmed that the simultaneous use mode configuration information is included in the system information, the terminal triggers an RRC connection setup procedure with the base station. In the base station for controlling sidelink communication,
A transmission unit for transmitting configuration information of a simultaneous use mode to a terminal to configure a first mode and a second mode, which are different radio resource allocation schemes, to be used simultaneously; And
Including a receiving unit for receiving buffer status information for sidelink communication from the terminal,
The transmission unit,
Transmitting radio resource information for the sidelink communication to the terminal based on the buffer status information,
The terminal,
A base station performing sidelink communication with another terminal using radio resources allocated by simultaneously using the first mode and the second mode based on the simultaneous use mode configuration information. The method of claim 19,
The first mode,
It is a resource allocation mode in which the base station allocates radio resources used to perform the sidelink communication,
The second mode,
The base station, characterized in that in a resource allocation mode in which the terminal selects a radio resource used to perform the sidelink communication from within a radio resource pool. The method of claim 19,
The above simultaneous use mode configuration information
A base station including information for configuring each of one or more sidelink logical channels or sidelink logical channel groups in association with any one of the first mode and the second mode. The method of claim 21,
The buffer status information,
And the buffer information of the one or more sidelink logical channels or sidelink logical channel groups configured in association with the first mode. The method of claim 21,
The terminal,
Performing a logical channel priority procedure only for the one or more sidelink logical channels or sidelink logical channel groups configured in connection with the first mode,
And a logical channel priority procedure is not performed for the one or more sidelink logical channels or sidelink logical channel groups configured in association with the second mode. The method of claim 19,
The simultaneous use mode configuration information is included in the system information,
The terminal, when the simultaneous use mode configuration information is received, the base station, characterized in that to trigger an RRC connection setup procedure with the base station.

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