WO2022070285A1

WO2022070285A1 - Terminal and communication method

Info

Publication number: WO2022070285A1
Application number: PCT/JP2020/037034
Authority: WO
Inventors: 翔平吉岡; 尚哉芝池; 聡永田
Original assignee: 株式会社Ｎｔｔドコモ
Priority date: 2020-09-29
Filing date: 2020-09-29
Publication date: 2022-04-07
Also published as: JPWO2022070285A1

Abstract

This terminal comprises: a control unit which selects a resource from among some resources in a resource selection window on the basis of at least one among information about Physical Sidelink Feedback Channel (PSFCH) occasions received from another terminal including at least one among a first terminal or a second terminal, and information about a PSFCH occasion scheduled to be transmitted or received by an own terminal; and a transmission unit which transmits data to the second terminal by using the selected resource.

Description

Terminal and communication method

The present invention relates to a terminal and a communication method in a wireless communication system.

In LTE (Long Term Evolution) and LTE successor systems (for example, LTE-A (LTE Advanced), NR (New Radio) (also referred to as 5G)), terminals communicate directly with each other without going through a base station. (Device to Device) technology is being studied (for example, Non-Patent Document 1).

D2D reduces the traffic between the terminal and the base station, and enables communication between the terminals even if the base station becomes unable to communicate due to a disaster or the like. In 3GPP (3rd Generation Partnership Project), D2D is referred to as "sidelink", but in the present specification, D2D, which is a more general term, is used. However, in the description of the embodiment described later, a side link is also used if necessary.

D2D communication includes D2D discovery (also referred to as D2D discovery) for discovering other terminals that can communicate, and D2D communication (D2D direct communication, D2D communication, direct communication between terminals) for direct communication between terminals. It is also roughly divided into communication, etc.). Hereinafter, when D2D communication, D2D discovery, etc. are not particularly distinguished, they are simply referred to as D2D. Further, a signal transmitted / received by D2D is called a D2D signal. Various use cases of services related to V2X (Vehicle to Everything) in NR are being studied (for example, Non-Patent Document 2).

Power saving is being considered as a strengthening of the NR side link. For example, in resource allocation mode 2 in which the terminal autonomously selects a resource, the terminal executes partial sensing that senses a limited resource in the sensing window, and the terminal performs partial sensing. Based on the result, select available resource candidates from the resource selection window.

In addition, HARQ (Hybrid automatic repeat request) feedback is supported on the NR side link. Here, since the timing of PSFCH (Physical Sidelink Feedback Channel) transmission depends on the timing at which the corresponding data is transmitted, it cannot be controlled by the terminal that transmits PSFCH. Therefore, depending on the timing, overlap between PSFCH and other channels may occur.

The present invention has been made in view of the above points, and an object thereof is to improve the efficiency of retransmission control in direct communication between terminals.

According to the disclosed technology, information related to PSFCH (Physical Sidelink Feedback Channel) opportunities received from other terminals including at least one of the first terminal or the second terminal, and information to be transmitted or received by the own terminal. A control unit that selects a resource from some of the resources in the resource selection window based on at least one of the information related to the PSFCH opportunity, and data to the second terminal using the selected resource. A terminal having a transmitting unit for transmitting is provided.

According to the disclosed technology, it is possible to improve the efficiency of retransmission control in direct communication between terminals.

It is a figure for demonstrating V2X. It is a figure for demonstrating the example (1) of the transmission mode of V2X. It is a figure for demonstrating the example (2) of the transmission mode of V2X. It is a figure for demonstrating the example (3) of the transmission mode of V2X. It is a figure for demonstrating the example (4) of the transmission mode of V2X. It is a figure for demonstrating the example (5) of the transmission mode of V2X. It is a figure for demonstrating the example (1) of the communication type of V2X. It is a figure for demonstrating the example (2) of the communication type of V2X. It is a figure for demonstrating the example (3) of the communication type of V2X. It is a sequence diagram which shows the operation example (1) of V2X. It is a sequence diagram which shows the operation example (2) of V2X. It is a sequence diagram which shows the operation example (3) of V2X. It is a sequence diagram which shows the operation example (4) of V2X. It is a figure which shows the example of a sensing operation. It is a figure which shows the example of the partial sensing operation. It is a figure which shows the example of communication in embodiment of this invention. It is a figure for demonstrating the example (1) of the information concerning a PSFCH opportunity in embodiment of this invention. It is a figure for demonstrating the example (2) of the information concerning a PSFCH opportunity in embodiment of this invention. It is a figure for demonstrating the example (3) of the information concerning a PSFCH opportunity in embodiment of this invention. It is a figure for demonstrating the example (4) of the information concerning a PSFCH opportunity in embodiment of this invention. It is a figure for demonstrating the example of resource selection in embodiment of this invention. It is a flowchart for demonstrating the example of resource selection in Embodiment of this invention. It is a figure which shows an example of the functional structure of the base station 10 in embodiment of this invention. It is a figure which shows an example of the functional structure of the terminal 20 in embodiment of this invention. It is a figure which shows an example of the hardware composition of the base station 10 or the terminal 20 in embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are examples, and the embodiments to which the present invention is applied are not limited to the following embodiments.

Existing technology is appropriately used in the operation of the wireless communication system according to the embodiment of the present invention. However, the existing technology is, for example, an existing LTE, but is not limited to the existing LTE. Further, the term "LTE" used in the present specification has a broad meaning including LTE-Advanced, a method after LTE-Advanced (eg, NR), or a wireless LAN (Local Area Network), unless otherwise specified. Shall have.

Further, in the embodiment of the present invention, the duplex system may be a TDD (Time Division Duplex) system, an FDD (Frequency Division Duplex) system, or any other system (for example, Flexible Duplex, etc.). Method may be used.

Further, in the embodiment of the present invention, "configuring" the radio parameter or the like may mean that a predetermined value is set in advance (Pre-configure), or the base station 10 or The radio parameter notified from the terminal 20 may be set.

FIG. 1 is a diagram for explaining V2X. In 3GPP, it is considered to realize V2X (Vehicle to Everything) or eV2X (enhanced V2X) by expanding the D2D function, and specifications are being promoted. As shown in FIG. 1, V2X is a part of ITS (Intelligent Transport Systems), V2V (Vehicle to Vehicle) which means a communication mode between vehicles, and a roadside installed between a vehicle and a roadside. V2I (Vehicle to Infrastructure), which means the communication mode between the machine (RSU: Road-Side Unit), V2N (Vehicle to Network), which means the communication mode between the vehicle and the ITS server, and , Is a general term for V2P (Vehicle to Pedestrian), which means a communication mode between a vehicle and a mobile terminal owned by a pedestrian.

Also, in 3GPP, V2X using LTE or NR cellular communication and terminal-to-terminal communication is being studied. V2X using cellular communication is also referred to as cellular V2X. In NR V2X, studies are underway to realize large capacity, low delay, high reliability, and QoS (Quality of Service) control.

Regarding LTE or NR V2X, it is expected that studies not limited to 3GPP specifications will be promoted in the future. For example, ensuring interoperability, reducing costs by implementing higher layers, using or switching between multiple RATs (RadioAccess Technology), compliance with regulations in each country, data acquisition, distribution, database management, and LTE or NR V2X platform. It is expected that the usage method will be examined.

In the embodiment of the present invention, it is mainly assumed that the communication device is mounted on the vehicle, but the embodiment of the present invention is not limited to the embodiment. For example, the communication device may be a terminal held by a person, the communication device may be a device mounted on a drone or an aircraft, and the communication device may be a base station, an RSU, a relay station (relay node), or the like. It may be a terminal or the like having a scheduling ability.

In addition, SL (Sidelink) may be distinguished based on any one or combination of UL (Uplink) or DL (Downlink) and the following 1) -4). Further, SL may have another name.
1) Time domain resource allocation 2) Frequency domain resource allocation 3) Reference synchronization signal (including SLSS (Sidelink Synchronization Signal))
4) Reference signal used for path loss measurement for transmission power control

Also, regarding SL or UL OFDM (Orthogonal Frequency Division Multiplexing), CP-OFDM (Cyclic-Prefix OFDM), DFT-S-OFDM (DiscreteFourierTransform-Spread-OFDM), Transform-precoded OFDM or Transfercoded Any of the OFDMs that are used may be applied.

In LTE SL, Mode 3 and Mode 4 are specified regarding the allocation of SL resources to the terminal 20. In Mode3, transmission resources are dynamically allocated by DCI (Downlink Control Information) transmitted from the base station 10 to the terminal 20. In addition, SPS (SemiPersistent Scheduling) is also possible in Mode3. In Mode 4, the terminal 20 autonomously selects a transmission resource from the resource pool.

The slot in the embodiment of the present invention may be read as a symbol, a mini slot, a subframe, a wireless frame, and a TTI (Transmission Time Interval). Further, the cell in the embodiment of the present invention may be read as a cell group, a carrier component, a BWP, a resource pool, a resource, a RAT (RadioAccess Technology), a system (including a wireless LAN), and the like.

In the embodiment of the present invention, the terminal 20 is not limited to the V2X terminal, and may be any type of terminal that performs D2D communication. For example, the terminal 20 may be a terminal owned by a user such as a smartphone, or may be an IoT (Internet of Things) device such as a smart meter.

FIG. 2 is a diagram for explaining an example (1) of the transmission mode of V2X. In the side link communication transmission mode shown in FIG. 2, in step 1, the base station 10 transmits the side link scheduling to the terminal 20A. Subsequently, the terminal 20A transmits PSCCH (Physical Sidelink Control Channel) and PSCH (Physical Sidelink Shared Channel) to the terminal 20B based on the received scheduling (step 2). The transmission mode of the side link communication shown in FIG. 2 may be referred to as the side link transmission mode 3 in LTE. In the side link transmission mode 3 in LTE, Uu-based side link scheduling is performed. Uu is a wireless interface between UTRAN (Universal Terrestrial Radio Access Network) and UE (User Equipment). The transmission mode of the side link communication shown in FIG. 2 may be referred to as the side link transmission mode 1 in NR.

FIG. 3 is a diagram for explaining an example (2) of the transmission mode of V2X. In the side-link communication transmission mode shown in FIG. 3, in step 1, terminal 20A transmits PSCCH and PSCH to terminal 20B using autonomously selected resources. The transmission mode of the side link communication shown in FIG. 3 may be referred to as the side link transmission mode 4 in LTE. In the side link transmission mode 4 in LTE, the UE itself executes resource selection.

FIG. 4 is a diagram for explaining an example (3) of the transmission mode of V2X. In the side-link communication transmission mode shown in FIG. 4, in step 1, terminal 20A transmits PSCCH and PSCH to terminal 20B using autonomously selected resources. Similarly, terminal 20B uses autonomously selected resources to transmit PSCCH and PSCH to terminal 20A (step 1). The transmission mode of the side link communication shown in FIG. 4 may be referred to as a side link transmission mode 2a in NR. In the side link transmission mode 2 in NR, the terminal 20 itself executes resource selection.

FIG. 5 is a diagram for explaining an example (4) of the transmission mode of V2X. In the side link communication transmission mode shown in FIG. 5, in step 0, the base station 10 transmits the side link grant to the terminal 20A via the RRC (Radio Resource Control) setting. Subsequently, the terminal 20A transmits the PSCH to the terminal 20B based on the received resource pattern (step 1). The transmission mode of the side link communication shown in FIG. 5 may be referred to as the side link transmission mode 2c in NR.

FIG. 6 is a diagram for explaining an example (5) of the transmission mode of V2X. In the side link communication transmission mode shown in FIG. 6, in step 1, the terminal 20A transmits the side link scheduling to the terminal 20B via the PSCCH. Subsequently, the terminal 20B transmits the PSCH to the terminal 20A based on the received scheduling (step 2). The transmission mode of the side link communication shown in FIG. 6 may be referred to as a side link transmission mode 2d in NR.

FIG. 7 is a diagram for explaining an example (1) of the communication type of V2X. The sidelink communication type shown in FIG. 7 is unicast. Terminal 20A transmits PSCCH and PSCH to terminal 20. In the example shown in FIG. 7, the terminal 20A unicasts to the terminal 20B and also unicasts to the terminal 20C.

FIG. 8 is a diagram for explaining an example (2) of the communication type of V2X. The sidelink communication type shown in FIG. 8 is group cast. Terminal 20A transmits PSCCH and PSCH to the group to which one or more terminals 20 belong. In the example shown in FIG. 8, the group includes the terminal 20B and the terminal 20C, and the terminal 20A performs a group cast to the group.

FIG. 9 is a diagram for explaining an example (3) of the communication type of V2X. The sidelink communication type shown in FIG. 9 is broadcast. Terminal 20A transmits PSCCH and PSCH to one or more terminals 20. In the example shown in FIG. 9, the terminal 20A broadcasts to the terminal 20B, the terminal 20C, and the terminal 20D. The terminal 20A shown in FIGS. 7 to 9 may be referred to as a header UE.

In addition, it is expected that HARQ (Hybrid automatic repeat request) will be supported for side link unicast and group cast in NR-V2X. Further, in NR-V2X, SFCI (Sidelink Feedback Control Information) including HARQ response is defined. Further, it is being considered that SFCI is transmitted via PSFCH (Physical Sidelink Feedback Channel).

In the following explanation, PSFCH is used in the transmission of HARQ-ACK on the side link, but this is an example. For example, PSCCH may be used to transmit HARQ-ACK on the side link, PSCH may be used to transmit HARQ-ACK on the side link, or other channels may be transmitted. It may be used to transmit HARQ-ACK on the side link.

In the following, for convenience, all the information reported by the terminal 20 in HARQ will be referred to as HARQ-ACK. This HARQ-ACK may be referred to as HARQ-ACK information. More specifically, a codebook applied to the HARQ-ACK information reported from the terminal 20 to the base station 10 or the like is called a HARQ-ACK codebook. The HARQ-ACK codebook defines a bit string of HARQ-ACK information. In addition to ACK, NACK is also transmitted by "HARQ-ACK".

FIG. 10 is a sequence diagram showing an operation example (1) of V2X. As shown in FIG. 10, the wireless communication system according to the embodiment of the present invention may have a terminal 20A and a terminal 20B. Although there are actually a large number of user devices, FIG. 10 shows terminals 20A and terminals 20B as examples.

Hereinafter, when the

terminals

20A, 20B, etc. are not particularly distinguished, they are simply described as "terminal 20" or "user device". Although FIG. 10 shows a case where both the terminal 20A and the terminal 20B are within the coverage of the cell as an example, the operation in the embodiment of the present invention can be applied even when the terminal 20B is outside the coverage.

As described above, in the present embodiment, the terminal 20 is a device mounted on a vehicle such as an automobile, and has a cellular communication function as a UE in LTE or NR and a side link function. There is. The terminal 20 may be a general mobile terminal (smartphone or the like). Further, the terminal 20 may be an RSU. The RSU may be a UE type RSU having a function of a UE, or may be a gNB type RSU having a function of a base station device.

Note that the terminal 20 does not have to be a device in one housing, and for example, even when various sensors are distributed and arranged in the vehicle, the device including the various sensors may be the terminal 20.

Further, the processing content of the transmission data of the side link of the terminal 20 is basically the same as the processing content of UL transmission in LTE or NR. For example, the terminal 20 scrambles and modulates the codeword of the transmission data to generate complex-valued symbols, maps the complex-valued symbols (transmission signal) to one or two layers, and performs precoding. Then, precoded complex-valued symbols are mapped to resource elements to generate a transmission signal (example: complex-valued time-domain SC-FDMA signal) and transmitted from each antenna port.

The base station 10 has a cellular communication function as a base station in LTE or NR, and a function for enabling communication of the terminal 20 in the present embodiment (example: resource pool setting, resource allocation, etc.). have. Further, the base station 10 may be an RSU (gNB type RSU).

Further, in the wireless communication system according to the embodiment of the present invention, the signal waveform used by the terminal 20 for SL or UL may be OFDMA, SC-FDMA, or other signal waveform. It may be.

In step S101, the terminal 20A autonomously selects a resource to be used for PSCCH and PSCH from a resource selection window having a predetermined period. The resource selection window may be set from the base station 10 to the terminal 20. Here, regarding a predetermined period of the resource selection window, the period may be specified by the implementation conditions of the terminal such as the processing time or the maximum allowable delay time of the packet, or the period may be specified in advance by the specifications. The predetermined period may be referred to as a section on the time domain.

In step S102 and step S103, the terminal 20A transmits SCI (Sidelink Control Information) by PSCCH and / or PSCH using the resource autonomously selected in step S101, and also transmits SL data by PSCH. For example, the terminal 20A may transmit the PSCCH with the same time resource as at least a part of the time resource of the PSCH, using the frequency resource adjacent to the frequency resource of the PSCH.

The terminal 20B receives the SCI (PSCCH and / or PSSCH) and SL data (PSSCH) transmitted from the terminal 20A. The received SCI may include information on PSFCH resources for the terminal 20B to transmit HARQ-ACK for receiving the data. The terminal 20A may include the information of the resource selected autonomously in the SCI and transmit it.

In step S104, the terminal 20B transmits HARQ-ACK for the received data to the terminal 20A by using the resource of PSFCH determined from the received SCI.

In step S105, the terminal 20A retransmits the PSCCH and PSCH to the terminal 20B when the HARQ-ACK received in step S104 indicates that the retransmission is requested, that is, when it is NACK (negative response). Terminal 20A may retransmit PSCCH and PSCH using autonomously selected resources.

If the HARQ control accompanied by the HARQ feedback is not executed, the steps S104 and S105 may not be executed.

FIG. 11 is a sequence diagram showing an operation example (2) of V2X. Blind retransmissions without HARQ control may be performed to improve transmission success rate or reach.

In step S201, the terminal 20A autonomously selects a resource to be used for PSCCH and PSCH from a resource selection window having a predetermined period. The resource selection window may be set from the base station 10 to the terminal 20.

In step S202 and step S203, the terminal 20A uses the resource autonomously selected in step S201 to transmit SCI by PSCCH and / or PSCH, and also transmits SL data by PSCH. For example, the terminal 20A may transmit the PSCCH with the same time resource as at least a part of the time resource of the PSCH, using the frequency resource adjacent to the frequency resource of the PSCH.

In step S204, the terminal 20A retransmits the SCI by PSCCH and / or the SL data by PSCH to the terminal 20B by using the resource autonomously selected in step S201. The retransmission in step S204 may be executed a plurality of times.

If the blind retransmission is not executed, step S204 may not be executed.

FIG. 12 is a sequence diagram showing an operation example (3) of V2X. The base station 10 may schedule the side link. That is, the base station 10 may determine the resource of the side link used by the terminal 20 and transmit the information indicating the resource to the terminal 20. Further, when HARQ control with HARQ feedback is applied, the base station 10 may transmit information indicating the resources of PSFCH to the terminal 20.

In step S301, the base station 10 performs SL scheduling by sending DCI (Downlink Control Information) to the terminal 20A by PDCCH. Hereinafter, for convenience, the DCI for SL scheduling will be referred to as SL scheduling DCI.

Further, in step S301, it is assumed that the base station 10 also transmits DCI for DL scheduling (which may be called DL allocation) to the terminal 20A by PDCCH. Hereinafter, for convenience, the DCI for DL scheduling is referred to as DL scheduling DCI. The terminal 20A that has received the DL scheduling DCI receives the DL data by PDSCH using the resource specified by the DL scheduling DCI.

In step S302 and step S303, the terminal 20A transmits SCI (Sidelink Control Information) by PSCCH and / or PSCH using the resource specified by SL scheduling DCI, and also transmits SL data by PSCH. In SL scheduling DCI, only PSCH resources may be specified. In this case, for example, the terminal 20A may transmit the PSCCH with the same time resource as at least a part of the time resource of the PSCH, using the frequency resource adjacent to the frequency resource of the PSCH.

The terminal 20B receives the SCI (PSCCH and / or PSSCH) and SL data (PSSCH) transmitted from the terminal 20A. The SCI received by the PSCCH and / or the PSSCH contains information on the resources of the PSFCH for the terminal 20B to transmit the HARQ-ACK for the reception of the data.

The information of the resource is included in the DL scheduling DCI or SL scheduling DCI transmitted from the base station 10 in step S301, and the terminal 20A acquires the information of the resource from the DL scheduling DCI or the SL scheduling DCI and SCI. Include in. Alternatively, the DCI transmitted from the base station 10 may not include the information of the resource, and the terminal 20A may autonomously include the information of the resource in the SCI and transmit the information.

In step S304, the terminal 20B transmits HARQ-ACK for the received data to the terminal 20A by using the resource of PSFCH determined from the received SCI.

In step S305, the terminal 20A has a PUCCH (or SL scheduling DCI) designated by the DL scheduling DCI (or SL scheduling DCI) at the timing specified by the DL scheduling DCI (or SL scheduling DCI) (for example, slot unit timing). (Physical uplink control channel) The HARQ-ACK is transmitted using the resource, and the base station 10 receives the HARQ-ACK. The HARQ-ACK codebook may include an ARQ-ACK generated based on the HARQ-ACK received from the terminal 20B or a PSFCH not received, and a HARQ-ACK for DL data. However, if DL data is not assigned, HARQ-ACK for DL data is not included. NR Rel. In 16, the HARQ-ACK codebook does not include HARQ-ACK for DL data.

If HARQ control with HARQ feedback is not executed, step S304 and / or step S305 may not be executed.

FIG. 13 is a sequence diagram showing an operation example (4) of V2X. As mentioned above, in the side link of NR, it is supported that the HARQ response is transmitted by PSFCH. As the PSFCH format, for example, the same format as the PUCCH (Physical Uplink Control Channel) format 0 can be used. That is, the PSFCH format may have a PRB (Physical Resource Block) size of 1, and ACK and NACK may be sequence-based formats identified by sequence and / or cyclic shift differences. The format of PSFCH is not limited to this. The resources of the PSFCH may be arranged in the symbol at the end of the slot or the multiple symbols at the end. Further, whether or not the period N is set in the PSFCH resource is specified in advance. The period N may be set or predetermined in slot units.

In FIG. 13, the vertical axis corresponds to the frequency domain and the horizontal axis corresponds to the time domain. The PSCCH may be arranged in one symbol at the beginning of the slot, may be arranged in a plurality of symbols from the beginning, or may be arranged in a plurality of symbols from a symbol other than the beginning. The PSFCH may be arranged in one symbol at the end of the slot, or may be arranged in a plurality of symbols at the end of the slot. In the above-mentioned "head of slot" and "end of slot", consideration of the symbol for AGC (Automatic Gain Control) and the symbol for transmission / reception switching may be omitted. That is, for example, when one slot is composed of 14 symbols, "the beginning of the slot" and "the end of the slot" mean that the 12 symbols excluding the beginning and ending symbols are the beginning and ending symbols, respectively. You may. In the example shown in FIG. 13, three subchannels are set in the resource pool, and two PSFCHs are arranged after three slots of the slot in which the PSSCH is arranged. The arrow from PSSCH to PSFCH shows an example of PSFCH associated with PSSCH.

When the HARQ response in the group cast of NR-V2X is group cast option 2 for transmitting ACK or NACK, it is necessary to determine the resource used for transmitting and receiving PSFCH. As shown in FIG. 13, in step S401, the terminal 20A, which is the transmitting side terminal 20, performs a group cast to the terminal 20B, the terminal 20C, and the terminal 20D, which are the receiving side terminals 20, via the SL-SCH. In a subsequent step S402, the terminal 20B uses PSFCH # B, the terminal 20C uses PSFCH # C, and the terminal 20D uses PSFCH # D to transmit a HARQ response to the terminal 20A. Here, as shown in the example of FIG. 13, when the number of available PSFCH resources is less than the number of receiving terminals 20 belonging to the group, it is necessary to determine how to allocate the PSFCH resources. .. The transmitting side terminal 20 may know the number of receiving side terminals 20 in the group cast. In group cast option 1, only NACK is transmitted as a HARQ response, and ACK is not transmitted.

FIG. 14 is a diagram showing an example of sensing operation. When partial sensing is not set from the upper layer in the LTE side link, the terminal 20 selects a resource and performs transmission as shown in FIG. As shown in FIG. 14, the terminal 20 performs sensing in the sensing window in the resource pool. By sensing, the terminal 20 receives a resource reservation field included in the SCI transmitted from another terminal 20, and identifies available resource candidates in the resource selection window in the resource pool based on the field. Subsequently, the terminal 20 randomly selects a resource from the available resource candidates. The resource selection window is a set of candidate resources to be used that are set in the resource pool. The resource selection window may be called by another name, for example, a setting related to resource selection, a target section for selecting a resource, and the like. The sensing window in LTE may be a section from a predetermined time point in the past to immediately before the trigger such as a packet generation. Sensing all the resources in the sensing window may be called full sensing. The sensing window may have another name indicating a section for sensing.

Further, as shown in FIG. 14, the resource pool setting may have a period. For example, the period may be a period of 10240 milliseconds. FIG. 14 is an example in which the subframe t ₀ ^SL to the subframe t _Tmax ^SL are set as the resource pool. The area of the resource pool in the cycle may be set by, for example, a bitmap.

Further, as shown in FIG. 14, it is assumed that the transmission trigger in the terminal 20 is generated in the subframe n and the priority of the transmission is _pTX . The terminal 20 can detect, for example, that another terminal 20 is transmitting the priority _pRX in the sensing window from the subframe t _{n-10 × Pstep} ^SL to the subframe t _n-1 ^SL . .. When SCI is detected in the sensing window and RSRP (Reference signal received power) exceeds the threshold value, the resource in the resource selection window corresponding to the SCI is excluded. Further, when SCI is detected in the sensing window and RSRP is less than the threshold value, the resource in the resource selection window corresponding to the SCI is not excluded. The threshold value may be, for example, the threshold values Th _{pTX, pRX} set or defined for each resource in the sensing window based on the priority _pTX and the priority _pRX .

Further, as in the subframe _tZ ^SL shown in FIG. 14, resources in the resource selection window that are candidates for resource reservation information corresponding to the resources in the sensing window that were not monitored for transmission are excluded. ..

In the resource selection window from subframe n + T ₁ to subframe n + T ₂ , as shown in FIG. 14, a resource occupied by another UE is identified, and a resource excluding the resource becomes a usable resource candidate. .. Assuming that the set of available resource candidates is SA, if SA is less than 20% of the resources in the resource selection window, the thresholds Th _pTX _{and pRX} _set for each resource in the sensing window are increased by 3 dB again. Resource identification may be performed. That is, by increasing the threshold values Th _{pTX and pRX} and executing resource identification again, the resources that are not excluded because RSRP is less than the threshold value may be increased. Further, the RSSI (Received signal strength indicator) of each resource of _SA may be measured, and the resource having the smallest _RSSI may be added to the set SB. The operation of adding the resource having the minimum _RSSI included in _SA to SB may be repeated until the set of resource candidates _SB becomes 20% or more of the resource selection window.

The lower layer of the terminal 20 may report _SB to the upper layer. The upper layer of the terminal 20 may execute a random selection for _SB to determine the resource to be used. The terminal 20 may execute the side link transmission using the determined resource. In addition, after securing the resource once, the terminal 20 may use the resource periodically without performing sensing a predetermined number of times (for example, _Cresel times).

FIG. 15 is a diagram showing an example of a partial sensing operation. When partial sensing is set from the upper layer in the LTE side link, the terminal 20 selects a resource and performs transmission as shown in FIG. As shown in FIG. 15, the terminal 20 performs partial sensing on a part of the sensing window in the resource pool. Resources that perform partial sensing may be referred to as sensing targets, sensing targets, sensing subframes, or sensing slots. By partial sensing, terminal 20 receives a resource reservation field contained in SCI transmitted from another terminal 20, and identifies available resource candidates in the resource selection window in the resource pool based on the field. .. Subsequently, the terminal 20 randomly selects a resource from the available resource candidates.

Further, as shown in FIG. 15, the resource pool setting may have a period. For example, the period may be a period of 10240 milliseconds. FIG. 15 is an example in which the subframe t ₀ ^SL to the subframe t _Tmax ^SL are set as a resource pool. The target area of the resource pool in the cycle may be set by, for example, a bitmap.

As shown in FIG. 15, it is assumed that the transmission trigger in the terminal 20 occurs in the subframe n and the priority of the transmission is _pTX . As shown in FIG. 15, among the subframes n + T ₁ to the subframe n + T ₂ , the _Y subframes from the subframe ty ^SL to the subframe _{ty + Y-1} ^SL may be set as the resource selection window. Further, as shown in FIG. 15, it is assumed that the transmission trigger in the terminal 20 is generated in the subframe n and the priority of the transmission is _pTX .

In the terminal 20, for example, another terminal 20 has priority p in one or a plurality of sensing targets from the subframe _{ty-k × Pstep} ^SL having the Y subframe length to the subframe ty _{+ Y-k × Pstep-1} ^SL . It can be detected that _RX is being transmitted. k may be, for example, a 10-bit bitmap. FIG. 15 shows an example in which the third and sixth bits of the bitmap k are set to "1" indicating that partial sensing is performed. That is, in FIG. 15, from the subframe _{ty-6 × Pstep} ^SL to the subframe ty _{+ Y-6 × Pstep-1} ^SL , and from the subframe _{ty-3 × Pstep} ^SL to the subframe ty _{+ Y-3 × Pstep-1.} Up to ^SL is set as the sensing target. As described above, the i-th bit of the bitmap k may correspond to the sensing target from the subframe _{ty-i × Pstep} ^SL to the subframe ty _{+ Y-i × Pstep-1} ^SL .

Note that y is an index in the Y subframe, k is set in advance by a 10-bit bitmap or is predetermined, and _Pstep is 100 ms. However, when SL communication is performed by DL and UL carriers, _Pstep is (U / (D + S + U)) * 100 ms. U corresponds to the number of UL slots, D corresponds to the number of DL slots, and S corresponds to the number of special slots.

If SCI is detected in one or more of the above sensing targets and RSRP exceeds the threshold, the resources in the resource selection window corresponding to the resource reservation field of the SCI are excluded. Further, when SCI is detected in the sensing target and RSRP is less than the threshold value, the resource in the resource selection window corresponding to the resource reservation field of the SCI is not excluded. The threshold value may be, for example, the threshold values Th _{pTX, pRX} set or defined for each resource in the sensing window based on the priority _pTX and the priority _pRX .

As shown in FIG. 15, in the resource selection window in which the Y subframe is set in the section [n + T ₁ , n + T ₂ ], the terminal 20 identifies the resource occupied by the other UE and excludes the resource. Is a available resource candidate. The Y subframes do not have to be continuous. Assuming that the set of available resource candidates is SA, if SA is less than 20% of the resources in the resource selection window, the thresholds Th _pTX _{and pRX} _set for each resource in the sensing window are increased by 3 dB again. Resource identification may be performed. That is, by increasing the threshold values Th _{pTX and pRX} and executing resource identification again, the resources that are not excluded because RSRP is less than the threshold value may be increased. Further, the _RSSI of each resource of SA may be measured, and the resource having the smallest _RSSI may be added to the set SB. The operation of adding the resource having the minimum _RSSI included in _SA to SB may be repeated until the set of resource candidates _SB becomes 20% or more of the resource selection window.

Although the operation of the transmitting side terminal 20 has been described with reference to FIGS. 14 and 15 described above, the receiving side terminal 20 detects data transmission from another terminal 20 based on the result of sensing or partial sensing, and the relevant terminal 20 is concerned. Data may be received from another terminal 20.

In the NR release 17 side link, power saving based on the above random resource selection and partial sensing is being considered. For example, in order to save power, the random resource selection and partial sensing of the side link in LTE release 14 may be applied to the resource allocation mode 2 of the NR release 16 side link. The terminal 20 to which the partial sensing is applied performs reception and sensing only in a specific slot in the sensing window.

Also, in the NR release 17 side link, eURLLC (enhanced Ultra Reliable Low Latency Communication) is being considered with inter-UE coordination as the baseline. For example, the terminal 20A may share information indicating a resource set with the terminal 20B, and the terminal 20B may consider the information in resource selection for transmission.

For example, when an overlap between PSFCH transmission and PSFCH reception occurs, it is necessary to drop one of the PSFCH. Also, for example, if there is an overlap between PSFCH transmission and PSFCH transmission, it may be necessary to reduce the transmission power or drop some PSFCH. Therefore, deterioration of reliability and delay characteristics occurs.

FIG. 16 is a diagram showing an example of communication in the embodiment of the present invention. In the embodiment of the present invention, as shown in FIG. 16, assuming a case where the terminal 20A, the terminal 20B, the terminal 20C and the terminal 20D exist, the case where the terminal 20C transmits data to the terminal 20B is targeted. do. Further, it is assumed that the terminal 20D transmits data to the terminal 20C.

In order to reduce the possibility that the PSFCH described above and other channels overlap, the terminal 20C operates on resource allocation based on at least one of the information shown in 1) -3) below. To execute.

1) Information related to PSFCH opportunities received by terminal 20C from terminal 20A 2) Information related to PSFCH opportunities received by terminal 20C from terminal 20B 3) Related to PSFCH opportunities transmitted or scheduled to be received by terminal 20C information

Hereinafter, the definition and acquisition method of the information shown in 1) -3) above, and the details of the operation related to resource allocation will be described. Unless otherwise specified, the information shown in 1) -3) above is the information used in the terminal 20C, and the operation related to resource allocation is an operation executed by the terminal 20C. The time resource allocation field in the embodiment of the present invention may be any field for indicating a future time resource, and may indicate one or a plurality of slots ahead. Similarly, the resource reservation cycle field (Resource reservation period field) may be a field for instructing a periodic time resource based on a specific periodicity, and may indicate the specific periodicity.

FIG. 17 is a diagram for explaining an example (1) of information relating to a PSFCH opportunity in the embodiment of the present invention. The information related to the PSFCH opportunity received by the terminal 20C from the terminal 20A may include the information shown in a) -c) below.

a) Information indicating a PSFCH opportunity corresponding to the PSCCH / PSSCH transmitted by the terminal 20A to the terminal 20B, which is also received by the terminal 20C. The PSFCH opportunity is referred to below, for example, as the PSFCH opportunity X1 shown in FIG.

b) The PSCCH / PSCH transmitted by the terminal 20A to the terminal 20B is also received by the terminal 20C, and corresponds to a resource based on (for example, instructing) a time resource allocation field included in the SCI in the PSCH / PSCH. Information indicating the PSFCH opportunity to do. The PSFCH opportunity is referred to below, for example, as the PSFCH opportunity X2 shown in FIG.

c) The PSCCH / PSCH transmitted by the terminal 20A to the terminal 20B is also received by the terminal 20C, and corresponds to a resource based on (for example, instructing) a resource reservation period field included in the SCI in the PSCH / PSCH. Information indicating the PSFCH opportunity to do. The PSFCH opportunity is referred to below as the PSFCH opportunity X3.

That is, the example (1) of the information relating to the PSFCH opportunity may be a PSFCH opportunity determined from the signal for data transmission and / or resource reservation. The PSCCH / PSSCH transmitted by the terminal 20A to the terminal 20B may be addressed to the group including the terminal 20B. Further, the information shown in a) -c) above may be valid only when the PSCCH / PSSCH transmitted from the terminal 20A or the resource selected by the terminal 20A requests HARQ feedback. In PSFCH opportunity X1, PSFCH opportunity X2, and PSFCH opportunity X3, the terminal 20B transmits the PSFCH, and the terminal 20A receives the PSFCH.

FIG. 18 is a diagram for explaining an example (2) of information relating to a PSFCH opportunity in the embodiment of the present invention. The information related to the PSFCH opportunity received by the terminal 20C from the terminal 20B may include the information shown in a) -c) below.

a) Information indicating a PSFCH opportunity corresponding to the PSCCH / PSSCH transmitted by the terminal 20B to the terminal 20A, which is also received by the terminal 20C. The PSFCH opportunity is referred to below, for example, as the PSFCH opportunity X4 shown in FIG.

b) Information indicating a PSFCH opportunity corresponding to a resource based on (for example, instructing) a time resource allocation field included in SCI in the PSCH / PSCH that the terminal 20C also receives the PSCCH / PSCH transmitted by the terminal 20B to the terminal 20A. .. The PSFCH opportunity is referred to below, for example, as the PSFCH opportunity X5 shown in FIG.

c) Information indicating a PSFCH opportunity corresponding to a resource based on (for example, instructing) a resource reservation cycle field included in the SCI in the PSCH / PSCH, the terminal 20C also receives the PSCCH / PSCH transmitted by the terminal 20B to the terminal 20A. .. The PSFCH opportunity is referred to below as the PSFCH opportunity X6.

That is, the example (a) -c) of the information relating to the PSFCH opportunity may be a PSFCH opportunity determined from the signal for data transmission and / or resource reservation. The PSCCH / PSSCH transmitted by the terminal 20B to the terminal 20A may be addressed to the group including the terminal 20A. Further, the information shown in a) -c) above may be valid only when the PSCCH / PSSCH transmitted from the terminal 20B or the resource selected by the terminal 20B requests HARQ feedback. In the PSFCH opportunity X4, PSFCH opportunity X5, and PSFCH opportunity X6, the terminal 20A transmits the PSFCH, and the terminal 20B receives the PSFCH.

Further, the information related to the PSFCH opportunity received by the terminal 20C from the terminal 20B is at least one information related to the resource usage schedule transmitted by the terminal 20B to the terminal 20C shown in d1) -d7) below. May be included. Information related to the resource usage schedule may be notified from the terminal 20B to the terminal 20C via, for example, RRC signaling, MAC signaling, or PHY layer signaling.

d1) Information indicating a PSFCH opportunity corresponding to the PSCCH / PSSCH received by the terminal 20B. The PSFCH opportunity will be referred to below as the PSFCH opportunity X7a.
d2) Information indicating a resource based on (for example, instructing) a time resource allocation field in PSCCH / PSSCH received by the terminal 20B.
d3) Information indicating a PSFCH opportunity corresponding to a resource based on (for example, instructing) a time resource allocation field in PSCCH / PSSCH received by terminal 20B. The PSFCH opportunity will be referred to below as the PSFCH opportunity X7b.
d4) Information indicating a resource based on (for example, instructing) a resource reservation cycle field in PSCCH / PSSCH received by the terminal 20B.
d5) Information indicating a PSFCH opportunity corresponding to a resource based on (for example, instructing) a resource reservation cycle field in PSCCH / PSSCH received by terminal 20B. The PSFCH opportunity will be referred to below as the PSFCH opportunity X7c.
d6) Information indicating the resource selected for transmission in the terminal 20B. For example, the resource may be a resource that is not reserved by the terminal 20B.
d7) Information indicating a PSFCH opportunity corresponding to a resource selected for transmission in terminal 20B. The PSFCH opportunity will be referred to below as the PSFCH opportunity X7d. For example, the resource may be a resource that is not reserved by the terminal 20B.

In the above d1) -d5), "received by the terminal 20B" may be replaced with "transmitted by the terminal 20B". Further, the priority related to the corresponding PSFCH opportunity or resource may be notified together with the information related to the resource usage schedule transmitted by the terminal 20B to the terminal 20C shown in d1) -d7). Further, the information shown in d1) -d7) may be valid only when the PSCCH / PSSCH transmitted from the terminal 20B or the resource selected by the terminal 20B requests HARQ feedback.

FIG. 19 is a diagram for explaining an example (3) of information relating to a PSFCH opportunity in the embodiment of the present invention. FIG. 20 is a diagram for explaining an example (4) of information relating to a PSFCH opportunity according to an embodiment of the present invention. The information related to the PSFCH opportunity that the terminal 20C plans to transmit or receive may include the information shown in a) -e) below.

a) Information indicating a PSFCH opportunity corresponding to an unreserved resource selected for transmission in terminal 20C. The PSFCH opportunity is referred to below, for example, as the PSFCH opportunity X8 shown in FIG.

b) Information indicating a PSFCH opportunity corresponding to the reserved resource selected for transmission in terminal 20C. The PSFCH opportunity is referred to below, for example, as the PSFCH opportunity X9 shown in FIG.

c) Information indicating a PSFCH opportunity corresponding to SCI in PSCCH / PSCH received by terminal 20C from terminal 20D. The PSFCH opportunity is referred to below, for example, as the PSFCH opportunity X10 shown in FIG.

d) Information indicating a PSFCH opportunity corresponding to a resource based on (eg, indicating) a time resource allocation field included in the SCI in the PSCCH / PSCH received by the terminal 20C from the terminal 20D. The PSFCH opportunity is referred to below, for example, as the PSFCH opportunity X11 shown in FIG.

e) Information indicating a PSFCH opportunity corresponding to a resource based on (eg, instructing) a resource reservation cycle field contained in SCI in PSCCH / PSCH received by terminal 20C from terminal 20D. The PSFCH opportunity is referred to below as the PSFCH opportunity X12.

The PSCCH / PSSCH transmitted by the terminal 20D to the terminal 20C in the above may be addressed to the group including the terminal 20C. Further, the information shown in a) -e) above may be valid only when the PSCCH / PSSCH transmitted from the terminal 20C or the resource selected by the terminal 20C requests HARQ feedback. Further, the terminal 20D may be the terminal 20A or the terminal 20B. In the PSFCH opportunity X8 and PSFCH opportunity X9, the terminal 20C receives the PSFCH. In the PSFCH opportunity X10, PSFCH opportunity X11, and PSFCH opportunity X12, the terminal 20C transmits the PSFCH.

By acquiring the information shown in 1), 2) and 3) above, the terminal 20C can identify the PSFCH opportunity that can be transmitted by the terminal 20B and can be received by the terminal 20C, and avoids the overlap of PSFCH. Can act to do. That is, the reliability of HARQ feedback can be improved.

FIG. 21 is a diagram for explaining an example of resource selection for transmission of a certain transport block in the embodiment of the present invention. In resource identification, all candidate resources included in the resource selection window before performing the resource exclusion operation are set as resource set S_A. Further, as shown in FIG. 21, a part or all of the resources of S_A are determined as the resource set S_B based on the information shown in 1), 2) and 3) above.

S_B is a set of PSCCH / PSCH resources corresponding to the PSFCH opportunity Y that the terminal 20B can transmit the PSFCH corresponding to the transport block transmitted by the terminal 20C to the terminal 20B and that the terminal 20C can receive. Is. That is, the PSFCH opportunity corresponding to the resource included in S_B may be able to be transmitted by the terminal 20B and may be received by the terminal 20C. The resource set S_C shown in FIG. 21 may be a resource of S_A not included in S_B.

Here, the PSFCH opportunity Y may be the PSFCH opportunity X1-X12 described above. Further, the PSFCH opportunity Y may be a PSFCH opportunity other than the PSFCH opportunity X1-X12. Further, the PSFCH opportunity Y may be determined based on the number of PSFCHs simultaneously transmitted by the terminal 20B. For example, when the number of PSFCHs transmitted simultaneously exceeds the number of PSFCHs that can be simultaneously transmitted by the terminal 20B at a certain PSFCH opportunity (that is, the number of PSFCHs transmitted simultaneously at the PSFCH opportunity before the resource selection is performed). , If the maximum number of PSFCHs that can be transmitted simultaneously has already been reached), the PSFCH opportunity may be excluded from the PSFCH opportunity Y. Further, when the terminal 20B simultaneously transmits a plurality of PSFCHs and the number of simultaneous transmissions requires that the transmission power of each PSFCH be reduced, the PSFCH opportunity that requires reduction of the transmission power is the PSFCH opportunity Y. May be excluded from.

Further, the PSFCH opportunity Y may be determined based on the priority. For example, if the priority of the PSFCH (or corresponding transport block) that the terminal 20B simultaneously transmits or receives at a PSFCH opportunity is higher than the priority of the transport block transmitted by the terminal 20C, the PSFCH. Opportunities may be excluded from PSFCH Opportunity Y. Further, if the transmission of the PSFCH corresponding to the transport block transmitted by the terminal 20C is not performed by, for example, priority control, the PSFCH opportunity may be excluded from the PSFCH opportunity Y.

FIG. 22 is a flowchart for explaining an example of resource selection in the embodiment of the present invention. FIG. 22 shows an example of an operation in which the terminal 20C selects a resource for transmission to the terminal 20B.

In step S1, the terminal 20C sets the resource set S_A to be identified. The resource set S_A may be the target of resource selection, or the above-mentioned resource set S_B of S_A may be the target of resource selection. That is, any of S_A in FIG. 22 may be replaced with S_B. Subsequently, the terminal 20C senses the resource corresponding to the resource set to be the target of resource selection (S2).

In step S3, the terminal 20C excludes the resource from the resource set and updates the resource set based on the RSRP by sensing. Here, the threshold value for determining RSRP for resource exclusion may be different between the resource included in the resource set S_B and the resource set S_C not included in S_B. For example, the threshold value applied to the resource included in the resource set S_C may be smaller than the threshold value applied to the resource included in the resource set S_B.

In step S4, the terminal 20C determines whether or not the specific resource amount of the resource amount included in the updated resource set by excluding the resource exceeds K% of the resource amount included in a certain resource set. .. The specific resource amount may be all of the resource amounts included in the updated resource set, or may be resources further included in the resource set S_B among the updated resource sets. The certain resource set may be the initial state of the resource set S_A or may be the initial state of the resource set S_B. For example, the certain resource set may be the resource set to be the target of the resource selection set in step S1.

For example, if the resources included in the resource set S_B among the updated resource sets do not exceed K% of the identified resource set S_A or the initial resource set, the process proceeds to step S6 and the terminal 20C sets a threshold value for determining RSRP. The change is made and step S3 is executed again. The change in the threshold value for determining RSRP may be, for example, an increase of 3 dB. On the other hand, if the resources included in the resource set S_B among the updated resource sets exceed K% of the identified resource set S_A or the initial resource set, the process proceeds to step S5.

In step S5, the terminal 20C reports the updated resource set to the upper layer. Subsequently, the terminal 20C executes resource selection from the updated resource set in the upper layer (S7). Here, the terminal 20C may select a resource from the resource set S_B. For example, when the resource included in S_B is included in the updated resource set, the terminal 20C may always select the resource included in S_B. Further, if the resource included in S_B is not included in the updated resource set, the terminal 20C may select any resource. Further, the probability of selecting a resource included in S_B included in the updated resource set may be higher than the probability of selecting a resource not included in S_B.

The operation shown in FIG. 22 above may be applied differently depending on the transmission priority. For example, the threshold value for determining RSRP or the ratio K% of the updated resource set to the initial resource set may be different for each transmission priority. Further, among the operations shown in FIG. 22 above, conventional operations may be applied to some steps. For example, in step S4, it may be determined whether or not the entire updated resource set exceeds K% of the initial resource set without being limited to the resources included in the resource set S_B. It should be noted that the operation shown in FIG. 22 above may be performed only when the transmission requires HARQ feedback. Further, the order of sensing and resource set determination may be reversed.

If the selected or reserved resource is not included in the resource set S_B in the terminal 20C, the resource may be reselected. Further, the terminal 20C may perform a resource revaluation triggered by the terminal 20C acquiring the information shown in 1), 2) and 3) above. Further, the operation shown in FIG. 22 may be applied to an operation related to an operation related to re-evaluation or pre-emption.

If a resource not included in the resource set S_B is selected in step S7 shown in FIG. 22, the corresponding PSFCH may be changed. For example, the corresponding PSFCH may be changed to any of the PSFCH opportunities Y described above. Further, for example, a dedicated PSFCH resource that is used only when a resource not included in the resource set S_B is selected may be defined. Also, for example, the corresponding PSFCH may be the next PSFCH opportunity in the time domain of the PSFCH opportunity before the change. Further, for example, the terminal 20C may notify that the PSFCH is changed by PSCCH / PSCH (for example, SCI) transmitted by the selected resource.

As described above, when the terminal 20C selects or allocates resources, the probability of transmitting data with resources corresponding to the PSFCH opportunity that the terminal 20B can transmit and the terminal 20C can receive can be increased. That is, the reliability of HARQ feedback can be improved.

The embodiment of the present invention may be applied to an operation in which one terminal 20 sets or allocates transmission resources of another terminal 20. That is, the transmission resource of the other terminal 20 may be set or allocated so as to satisfy the conditions of resource selection or resource allocation according to the embodiment of the present invention.

The above embodiment is not limited to the V2X terminal, and may be applied to a terminal that performs D2D communication.

The operation according to the above embodiment may be executed only in a specific resource pool. For example, the operation according to the above embodiment may be executed only in the resource pool that can be used by the terminal 20 after release 17.

The operation according to the above embodiment may be applied between the terminals 20 in which the PC5-RRC connection is established.

The operation according to the above embodiment may be applied to either the case where the transmission is a group cast or the case where the transmission is a unicast.

The UE or terminal 20 may be a plurality of UEs or terminals 20 and may belong to the same group.

According to the above embodiment, the terminal 20 can specify the PSFCH opportunity that the destination terminal 20 can transmit and the own terminal can receive, and the overlap of the PSFCH can be avoided. In addition, the terminal 20 can transmit data with resources corresponding to the PSFCH opportunity that can be transmitted and can be received by the own terminal.

That is, in direct communication between terminals, the efficiency of retransmission control can be improved.

(Device configuration)
Next, a functional configuration example of the base station 10 and the terminal 20 that execute the processes and operations described so far will be described. The base station 10 and the terminal 20 include a function for carrying out the above-described embodiment. However, the base station 10 and the terminal 20 may each have only a part of the functions in the embodiment.

<Base station 10>
FIG. 23 is a diagram showing an example of the functional configuration of the base station 10. As shown in FIG. 23, the base station 10 has a transmission unit 110, a reception unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in FIG. 23 is only an example. Any function classification and name of the functional unit may be used as long as the operation according to the embodiment of the present invention can be performed.

The transmission unit 110 includes a function of generating a signal to be transmitted to the terminal 20 side and transmitting the signal wirelessly. The receiving unit 120 includes a function of receiving various signals transmitted from the terminal 20 and acquiring information of, for example, a higher layer from the received signals. Further, the transmission unit 110 has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signal, DL reference signal, etc. to the terminal 20.

The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20 in the storage device, and reads them out from the storage device as needed. The content of the setting information is, for example, information related to the setting of D2D communication.

As described in the embodiment, the control unit 140 performs processing related to the setting for the terminal 20 to perform D2D communication. Further, the control unit 140 transmits the scheduling of D2D communication and DL communication to the terminal 20 via the transmission unit 110. Further, the control unit 140 receives information related to the HARQ response of the D2D communication and the DL communication from the terminal 20 via the reception unit 120. The function unit related to signal transmission in the control unit 140 may be included in the transmission unit 110, and the function unit related to signal reception in the control unit 140 may be included in the reception unit 120.

<Terminal 20>
FIG. 24 is a diagram showing an example of the functional configuration of the terminal 20. As shown in FIG. 24, the terminal 20 has a transmission unit 210, a reception unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in FIG. 24 is only an example. Any function classification and name of the functional unit may be used as long as the operation according to the embodiment of the present invention can be performed.

The transmission unit 210 creates a transmission signal from the transmission data and wirelessly transmits the transmission signal. The receiving unit 220 wirelessly receives various signals and acquires a signal of a higher layer from the received signal of the physical layer. Further, the receiving unit 220 has a function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signal, reference signal and the like transmitted from the base station 10. Further, for example, the transmission unit 210 may use PSCCH (Physical Sidelink Control Channel), PSSCH (Physical Sidelink Shared Channel), PSDCH (Physical Sidelink Discovery Channel), PSBCH (Physical Sidelink Broadcast Channel) as D2D communication on another terminal 20. Etc. are transmitted, and the receiving unit 220 receives PSCCH, PSSCH, PSDCH, PSBCH, etc. from the other terminal 20.

The setting unit 230 stores various setting information received from the base station 10 or the terminal 20 by the receiving unit 220 in the storage device, and reads it out from the storage device as needed. The setting unit 230 also stores preset setting information. The content of the setting information is, for example, information related to the setting of D2D communication.

As described in the embodiment, the control unit 240 controls D2D communication for establishing an RRC connection with another terminal 20. In addition, the control unit 240 performs processing related to power saving operation. Further, the control unit 240 performs processing related to HARQ of D2D communication and DL communication. Further, the control unit 240 transmits information related to the HARQ response of the D2D communication and the DL communication from the base station 10 to the other terminal 20 scheduled to the base station 10. Further, the control unit 240 may schedule D2D communication to another terminal 20. Further, the control unit 240 may autonomously select a resource to be used for D2D communication from the resource selection window based on the sensing result, or may execute re-evaluation or preemption. Further, the control unit 240 performs processing related to power saving in transmission / reception of D2D communication. In addition, the control unit 240 performs processing related to cooperation between terminals in D2D communication. The function unit related to signal transmission in the control unit 240 may be included in the transmission unit 210, and the function unit related to signal reception in the control unit 240 may be included in the reception unit 220.

(Hardware configuration)
The block diagram (FIGS. 23 and 24) used in the description of the above embodiment shows a block of functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Further, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one physically or logically coupled device, or two or more physically or logically separated devices can be directly or indirectly (eg, for example). , Wired, wireless, etc.) and may be realized using these plurality of devices. The functional block may be realized by combining the software with the one device or the plurality of devices.

Functions include judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, selection, establishment, comparison, assumption, expectation, and assumption. Broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc., but limited to these I can't. For example, a functional block (configuration unit) that makes transmission function is called a transmitting unit (transmitting unit) or a transmitter (transmitter). In each case, as described above, the realization method is not particularly limited.

For example, the base station 10, the terminal 20, and the like in one embodiment of the present disclosure may function as a computer that processes the wireless communication method of the present disclosure. FIG. 25 is a diagram showing an example of the hardware configuration of the base station 10 and the terminal 20 according to the embodiment of the present disclosure. The above-mentioned base station 10 and terminal 20 are physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like. May be good.

In the following explanation, the word "device" can be read as a circuit, device, unit, etc. The hardware configuration of the base station 10 and the terminal 20 may be configured to include one or more of the devices shown in the figure, or may be configured not to include some of the devices.

For each function in the base station 10 and the terminal 20, by loading predetermined software (program) on the hardware such as the processor 1001 and the storage device 1002, the processor 1001 performs an calculation and controls the communication by the communication device 1004. It is realized by controlling at least one of reading and writing of data in the storage device 1002 and the auxiliary storage device 1003.

The processor 1001 operates, for example, an operating system to control the entire computer. The processor 1001 may be configured by a central processing unit (CPU: Central Processing Unit) including an interface with a peripheral device, a control device, an arithmetic unit, a register, and the like. For example, the above-mentioned control unit 140, control unit 240, and the like may be realized by the processor 1001.

Further, the processor 1001 reads a program (program code), a software module, data, or the like from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiment is used. For example, the control unit 140 of the base station 10 shown in FIG. 23 may be realized by a control program stored in the storage device 1002 and operated by the processor 1001. Further, for example, the control unit 240 of the terminal 20 shown in FIG. 24 may be realized by a control program stored in the storage device 1002 and operated by the processor 1001. Although it has been described that the various processes described above are executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. Processor 1001 may be mounted by one or more chips. The program may be transmitted from the network via a telecommunication line.

The storage device 1002 is a computer-readable recording medium, and is, for example, by at least one of ROM (ReadOnlyMemory), EPROM (ErasableProgrammableROM), EEPROM (ElectricallyErasableProgrammableROM), RAM (RandomAccessMemory), and the like. It may be configured. The storage device 1002 may be referred to as a register, a cache, a main memory (main storage device), or the like. The storage device 1002 can store a program (program code), a software module, or the like that can be executed to implement the communication method according to the embodiment of the present disclosure.

The auxiliary storage device 1003 is a computer-readable recording medium, and is, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, an optical magnetic disk (for example, a compact disk, a digital versatile disk, Blu). -It may be composed of at least one of a ray (registered trademark) disk), a smart card, a flash memory (for example, a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, and the like. The storage medium described above may be, for example, a database, server or other suitable medium containing at least one of the storage device 1002 and the auxiliary storage device 1003.

The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, or the like. The communication device 1004 includes, for example, a high frequency switch, a duplexer, a filter, a frequency synthesizer, and the like in order to realize at least one of frequency division duplex (FDD: Frequency Division Duplex) and time division duplex (TDD: Time Division Duplex). It may be composed of. For example, the transmission / reception antenna, the amplifier unit, the transmission / reception unit, the transmission line interface, and the like may be realized by the communication device 1004. The transmission / reception unit may be physically or logically separated from each other in the transmission unit and the reception unit.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts an input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

Further, each device such as the processor 1001 and the storage device 1002 is connected by the bus 1007 for communicating information. The bus 1007 may be configured by using a single bus, or may be configured by using a different bus for each device.

Further, the base station 10 and the terminal 20 are hardware such as a microprocessor, a digital signal processor (DSP: Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array). It may be configured to include, and a part or all of each functional block may be realized by the hardware. For example, processor 1001 may be implemented using at least one of these hardware.

(Summary of embodiments)
As described above, according to the embodiment of the present invention, information relating to a PSFCH (Physical Sidelink Feedback Channel) opportunity received from another terminal including at least one of the first terminal or the second terminal, And the control unit that selects a resource from some resources in the resource selection window based on at least one of the information related to the PSFCH opportunity that the own terminal plans to send or receive, and the selected resource is used. A terminal having a transmission unit for transmitting data to the second terminal is provided.

With the above configuration, the terminal 20 can specify the PSFCH opportunity that the destination terminal 20 can transmit and the own terminal can receive, and the overlap of PSFCH can be avoided. In addition, the terminal 20 can transmit data with resources corresponding to the PSFCH opportunity that can be transmitted and can be received by the own terminal. That is, in direct communication between terminals, the efficiency of retransmission control can be improved.

The information relating to the PSFCH opportunity received from the other terminal may include at least one of the information relating to the PSFCH opportunity received from the first terminal and the information relating to the PSFCH opportunity received from the second terminal. With this configuration, the terminal 20 can specify the PSFCH opportunity that the destination terminal 20 can transmit and the own terminal can receive, and can avoid the overlap of PSFCH.

Information indicating a PSFCH opportunity corresponding to a signal received by the second terminal, information indicating a resource based on a time resource allocation field included in control information in the signal received by the second terminal, the second terminal. Information indicating the PSFCH opportunity corresponding to the resource based on the time resource allocation field included in the control information in the signal received by the terminal, the resource based on the resource reservation cycle field included in the control information in the signal received by the second terminal. Information indicating the PSFCH opportunity corresponding to the resource based on the resource reservation cycle field included in the control information in the signal received by the second terminal, and the resource selected for transmission by the second terminal. Further having a receiver that receives at least one of the information shown and the information indicating the PSFCH opportunity corresponding to the resource selected for transmission by the second terminal from the second terminal via signaling. You may. With this configuration, the terminal 20 can specify the PSFCH opportunity that the destination terminal 20 can transmit and the own terminal can receive, and can avoid the overlap of PSFCH.

In the PSFCH opportunity corresponding to the part of the resource, the second terminal can transmit the PSFCH corresponding to the data to be transmitted to the second terminal, and the own terminal can receive the PSFCH. It may be possible. With this configuration, the terminal 20 can specify the PSFCH opportunity that the destination terminal 20 can transmit and the own terminal can receive, and can avoid the overlap of PSFCH. In addition, the terminal 20 can transmit data with resources corresponding to the PSFCH opportunity that can be transmitted and can be received by the own terminal.

If some of the resources do not exceed a predetermined ratio in the resource selection window, the threshold value for determining RSRP (Reference signal received power) is changed, and resources are again assigned to the resource selection window based on the threshold value. You may perform the action to exclude. With this configuration, the terminal 20 can specify the PSFCH opportunity that the destination terminal 20 can transmit and the own terminal can receive, and can avoid the overlap of PSFCH. In addition, the terminal 20 can transmit data with resources corresponding to the PSFCH opportunity that can be transmitted and can be received by the own terminal.

Further, according to the embodiment of the present invention, information relating to a PSFCH (Physical Sidelink Feedback Channel) opportunity received from another terminal including at least one of the first terminal or the second terminal, and transmission by the own terminal. Alternatively, the control procedure for selecting a resource from some of the resources in the resource selection window based on at least one of the information relating to the PSFCH opportunity to be received and the data using the selected resource are described above. A communication method is provided in which the terminal executes a transmission procedure for transmitting to the second terminal.

(Supplement to the embodiment)
Although the embodiments of the present invention have been described above, the disclosed inventions are not limited to such embodiments, and those skilled in the art will understand various modifications, modifications, alternatives, substitutions, and the like. There will be. Although explanations have been given using specific numerical examples in order to promote understanding of the invention, these numerical values are merely examples and any appropriate value may be used unless otherwise specified. The classification of items in the above description is not essential to the present invention, and the items described in two or more items may be used in combination as necessary, and the items described in one item may be used in another item. May apply (as long as there is no conflict) to the matters described in. The boundary of the functional part or the processing part in the functional block diagram does not always correspond to the boundary of the physical component. The operation of the plurality of functional units may be physically performed by one component, or the operation of one functional unit may be physically performed by a plurality of components. Regarding the processing procedure described in the embodiment, the processing order may be changed as long as there is no contradiction. For convenience of processing, the base station 10 and the terminal 20 have been described with reference to functional block diagrams, but such devices may be implemented in hardware, software, or a combination thereof. The software operated by the processor of the base station 10 according to the embodiment of the present invention and the software operated by the processor of the terminal 20 according to the embodiment of the present invention are random access memory (RAM), flash memory, and read-only memory, respectively. It may be stored in (ROM), EPROM, EEPROM, registers, hard disk (HDD), removable disk, CD-ROM, database, server or any other suitable storage medium.

Further, the notification of information is not limited to the embodiment / embodiment described in the present disclosure, and may be performed by using another method. For example, information notification includes physical layer signaling (for example, DCI (Downlink Control Information), UCI (Uplink Control Information)), higher layer signaling (for example, RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, etc. It may be carried out by broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or a combination thereof. RRC signaling may be referred to as an RRC message, for example, RRC. It may be a connection setup (RRCConnectionSetup) message, an RRC connection reconfiguration (RRCConnectionReconfiguration) message, or the like.

Each aspect / embodiment described in the present disclosure includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), and 5G (5th generation mobile communication). system), FRA (Future Radio Access), NR (new Radio), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)) )), LTE 802.16 (WiMAX®), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth®, and other systems that utilize appropriate systems and have been extended based on these. It may be applied to at least one of the next generation systems. Further, a plurality of systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A and 5G).

The order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in the present specification may be changed as long as there is no contradiction. For example, the methods described in the present disclosure present elements of various steps using exemplary order, and are not limited to the particular order presented.

In some cases, the specific operation performed by the base station 10 in the present specification may be performed by its upper node (upper node). In a network consisting of one or more network nodes having a base station 10, various operations performed for communication with the terminal 20 are performed by the base station 10 and other network nodes other than the base station 10 ( For example, MME, S-GW, etc. are conceivable, but it is clear that it can be done by at least one of these). In the above example, the case where there is one network node other than the base station 10 is illustrated, but the other network node may be a combination of a plurality of other network nodes (for example, MME and S-GW). ..

The information, signals, etc. described in the present disclosure can be output from the upper layer (or lower layer) to the lower layer (or upper layer). Input / output may be performed via a plurality of network nodes.

The input / output information and the like may be stored in a specific location (for example, a memory) or may be managed using a management table. Information to be input / output may be overwritten, updated, or added. The output information and the like may be deleted. The input information or the like may be transmitted to another device.

The determination in the present disclosure may be made by a value represented by 1 bit (0 or 1), by a boolean value (Boolean: true or false), or by comparison of numerical values (for example). , Comparison with a predetermined value).

Software, whether called software, firmware, middleware, microcode, hardware description language, or other names, instructions, instruction sets, codes, code segments, program codes, programs, subprograms, software modules. , Applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, features, etc. should be broadly interpreted.

Further, software, instructions, information, etc. may be transmitted and received via a transmission medium. For example, a website where the software uses at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL: Digital Subscriber Line), etc.) and wireless technology (infrared, microwave, etc.). When transmitted from a server or other remote source, at least one of these wired and wireless technologies is included within the definition of transmission medium.

The information, signals, etc. described in this disclosure may be represented using any of a variety of different techniques. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description are voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these. It may be represented by a combination of.

The terms described in the present disclosure and the terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Also, the signal may be a message. Further, the component carrier (CC: Component Carrier) may be referred to as a carrier frequency, a cell, a frequency carrier, or the like.

The terms "system" and "network" used in this disclosure are used interchangeably.

Further, the information, parameters, etc. described in the present disclosure may be expressed using an absolute value, a relative value from a predetermined value, or another corresponding information. It may be represented. For example, the radio resource may be one indicated by an index.

The names used for the above parameters are not limited in any respect. Further, mathematical formulas and the like using these parameters may differ from those expressly disclosed in this disclosure. Since the various channels (eg, PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, the various names assigned to these various channels and information elements are in any respect limited names. is not.

In this disclosure, "base station (BS: Base Station)", "wireless base station", "base station", "fixed station", "NodeB", "eNodeB (eNB)", "gNodeB (gNodeB) gNB) ”,“ access point ”,“ transmission point ”,“ reception point ”,“ transmission / reception point ”,“ cell ”,“ sector ”,“ Terms such as "cell group", "carrier", and "component carrier" may be used interchangeably. Base stations are sometimes referred to by terms such as macrocells, small cells, femtocells, and picocells.

The base station can accommodate one or more (eg, 3) cells. When a base station accommodates multiple cells, the entire base station coverage area can be divided into multiple smaller areas, each smaller area being a base station subsystem (eg, a small indoor base station (RRH:)). Communication services can also be provided by (Remote Radio Head). The term "cell" or "sector" is a part or all of the coverage area of at least one of the base stations and base station subsystems that provide communication services in this coverage. Point to.

In the present disclosure, terms such as "mobile station (MS: Mobile Station)", "user terminal", "user device (UE: User Equipment)", and "terminal" may be used interchangeably. ..

Mobile stations can be used by those skilled in the art as subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobile terminals, wireless. It may also be referred to as a terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable term.

At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, or the like. At least one of the base station and the mobile station may be a device mounted on the mobile body, a mobile body itself, or the like. The moving body may be a vehicle (eg, car, airplane, etc.), an unmanned moving body (eg, drone, self-driving car, etc.), or a robot (manned or unmanned). ) May be. It should be noted that at least one of the base station and the mobile station includes a device that does not necessarily move during communication operation. For example, at least one of a base station and a mobile station may be an IoT (Internet of Things) device such as a sensor.

Further, the base station in the present disclosure may be read by the user terminal. For example, the communication between the base station and the user terminal is replaced with the communication between a plurality of terminals 20 (for example, it may be referred to as D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). Each aspect / embodiment of the present disclosure may be applied to the configuration. In this case, the terminal 20 may have the functions of the base station 10 described above. Further, the words such as "up" and "down" may be read as words corresponding to the communication between terminals (for example, "side"). For example, the upstream channel, the downstream channel, and the like may be read as a side channel.

Similarly, the user terminal in the present disclosure may be read as a base station. In this case, the base station may have the functions of the above-mentioned user terminal.

The terms "determining" and "determining" used in this disclosure may include a wide variety of actions. "Judgment" and "decision" are, for example, judgment (judging), calculation (calculating), calculation (computing), processing (processing), derivation (deriving), investigation (investigating), search (looking up, search, inquiry). It may include (eg, searching in a table, database or another data structure), ascertaining as "judgment" or "decision". Also, "judgment" and "decision" are receiving (for example, receiving information), transmitting (for example, transmitting information), input (input), output (output), and access. It may include (for example, accessing data in memory) to be regarded as "judgment" or "decision". In addition, "judgment" and "decision" are considered to be "judgment" and "decision" when the things such as solving, selecting, choosing, establishing, and comparing are regarded as "judgment" and "decision". Can include. That is, "judgment" and "decision" may include considering some action as "judgment" and "decision". Further, "judgment (decision)" may be read as "assuming", "expecting", "considering" and the like.

The terms "connected", "coupled", or any variation thereof, mean any direct or indirect connection or connection between two or more elements and each other. It can include the presence of one or more intermediate elements between two "connected" or "combined" elements. The connection or connection between the elements may be physical, logical, or a combination thereof. For example, "connection" may be read as "access". As used in the present disclosure, the two elements use at least one of one or more wires, cables and printed electrical connections, and as some non-limiting and non-comprehensive examples, the radio frequency domain. Can be considered to be "connected" or "coupled" to each other using electromagnetic energy having wavelengths in the microwave and light (both visible and invisible) regions.

The reference signal can also be abbreviated as RS (Reference Signal), and may be called a pilot (Pilot) depending on the applied standard.

The statement "based on" used in this disclosure does not mean "based on" unless otherwise stated. In other words, the statement "based on" means both "based only" and "at least based on".

Any reference to elements using designations such as "first" and "second" as used in this disclosure does not generally limit the quantity or order of those elements. These designations can be used in the present disclosure as a convenient way to distinguish between two or more elements. Therefore, references to the first and second elements do not mean that only two elements can be adopted, or that the first element must somehow precede the second element.

The "means" in the configuration of each of the above devices may be replaced with a "part", a "circuit", a "device", or the like.

When "include", "including" and variations thereof are used in the present disclosure, these terms are as comprehensive as the term "comprising". Is intended. Moreover, the term "or" used in the present disclosure is intended not to be an exclusive OR.

The wireless frame may be composed of one or more frames in the time domain. Each one or more frames in the time domain may be referred to as a subframe. The subframe may further be composed of one or more slots in the time domain. The subframe may have a fixed time length (eg, 1 ms) that does not depend on numerology.

The numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel. Numerology includes, for example, subcarrier interval (SCS: SubCarrier Spacing), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI: Transmission Time Interval), number of symbols per TTI, wireless frame configuration, and transmitter / receiver. It may indicate at least one of a specific filtering process performed in the frequency domain, a specific windowing process performed by the transmitter / receiver in the time domain, and the like.

The slot may be composed of one or more symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbol, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbol, etc.) in the time region. Slots may be time units based on numerology.

The slot may include a plurality of mini slots. Each minislot may be composed of one or more symbols in the time domain. Further, the mini slot may be referred to as a sub slot. The minislot may consist of a smaller number of symbols than the slot. The PDSCH (or PUSCH) transmitted in units of time larger than the minislot may be referred to as PDSCH (or PUSCH) mapping type A. The PDSCH (or PUSCH) transmitted using the minislot may be referred to as PDSCH (or PUSCH) mapping type B.

The wireless frame, subframe, slot, minislot and symbol all represent the time unit when transmitting a signal. The radio frame, subframe, slot, minislot and symbol may have different names corresponding to each.

For example, one subframe may be called a transmission time interval (TTI), a plurality of consecutive subframes may be called TTI, and one slot or one minislot may be called TTI. You may. That is, at least one of the subframe and TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (eg, 1-13 symbols), or a period longer than 1 ms. May be. The unit representing TTI may be called a slot, a mini slot, or the like instead of a subframe.

Here, TTI refers to, for example, the minimum time unit of scheduling in wireless communication. For example, in the LTE system, the base station schedules each terminal 20 to allocate radio resources (frequency bandwidth that can be used in each terminal 20, transmission power, etc.) in TTI units. The definition of TTI is not limited to this.

TTI may be a transmission time unit such as a channel-encoded data packet (transport block), a code block, or a code word, or may be a processing unit such as scheduling or link adaptation. When a TTI is given, the time interval (for example, the number of symbols) to which the transport block, code block, code word, etc. are actually mapped may be shorter than the TTI.

When one slot or one mini slot is called TTI, one or more TTIs (that is, one or more slots or one or more mini slots) may be the minimum time unit for scheduling. Further, the number of slots (number of mini-slots) constituting the minimum time unit of the scheduling may be controlled.

A TTI having a time length of 1 ms may be referred to as a normal TTI (TTI in LTE Rel. 8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a slot, or the like. A TTI shorter than a normal TTI may be referred to as a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a minislot, a subslot, a slot, and the like.

The long TTI (eg, normal TTI, subframe, etc.) may be read as a TTI having a time length of more than 1 ms, and the short TTI (eg, shortened TTI, etc.) may be read as a TTI less than the TTI length of the long TTI and 1 ms. It may be read as TTI having the above TTI length.

The resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or a plurality of continuous subcarriers in the frequency domain. The number of subcarriers contained in the RB may be the same regardless of the numerology, and may be, for example, 12. The number of subcarriers contained in the RB may be determined based on numerology.

Further, the time domain of the RB may include one or more symbols, and may have a length of 1 slot, 1 mini slot, 1 subframe, or 1 TTI. Each 1TTI, 1 subframe, etc. may be composed of one or a plurality of resource blocks.

One or more RBs include a physical resource block (PRB: Physical RB), a sub-carrier group (SCG: Sub-Carrier Group), a resource element group (REG: Resource Element Group), a PRB pair, an RB pair, and the like. May be called.

Further, the resource block may be composed of one or a plurality of resource elements (RE: Resource Element). For example, 1RE may be a radio resource area of 1 subcarrier and 1 symbol.

The bandwidth part (BWP: Bandwidth Part) (which may also be called partial bandwidth) may represent a subset of consecutive common resource blocks (RBs) for a certain neurology in a carrier. Here, the common RB may be specified by the index of the RB with respect to the common reference point of the carrier. PRBs may be defined in a BWP and numbered within that BWP.

The BWP may include a BWP for UL (UL BWP) and a BWP for DL (DL BWP). One or more BWPs may be set in one carrier for the terminal 20.

At least one of the configured BWPs may be active, and the terminal 20 does not have to assume that a predetermined signal / channel is transmitted or received outside the active BWP. In addition, "cell", "carrier" and the like in this disclosure may be read as "BWP".

The above-mentioned structures such as wireless frames, subframes, slots, mini-slots and symbols are merely examples. For example, the number of subframes contained in a radio frame, the number of slots per subframe or radio frame, the number of minislots contained within a slot, the number of symbols and RBs contained in a slot or minislot, included in the RB. The number of subcarriers, the number of symbols in the TTI, the symbol length, the cyclic prefix (CP: Cyclic Prefix) length, and other configurations can be changed in various ways.

In the present disclosure, if articles are added by translation, for example, a, an and the in English, the disclosure may include the plural nouns following these articles.

In the present disclosure, the term "A and B are different" may mean "A and B are different from each other". The term may mean that "A and B are different from C". Terms such as "separate" and "combined" may be interpreted in the same way as "different".

Each aspect / embodiment described in the present disclosure may be used alone, in combination, or may be switched and used according to the execution. Further, the notification of predetermined information (for example, the notification of "being X") is not limited to the explicit one, but is performed implicitly (for example, the notification of the predetermined information is not performed). May be good.

In the present disclosure, the terminal 20A is an example of the first terminal. The terminal 20B is an example of a second terminal.

Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure may be implemented as amendments and modifications without departing from the spirit and scope of the present disclosure as determined by the description of the scope of claims. Therefore, the description of this disclosure is for purposes of illustration and does not have any limiting meaning to this disclosure.

10 Base station 110 Transmission unit 120 Reception unit 130 Setting unit 140 Control unit 20 Terminal 210 Transmission unit 220 Reception unit 230 Setting unit 240 Control unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device

Claims

Of the information related to PSFCH (Physical Sidelink Feedback Channel) opportunities received from other terminals including at least either the first terminal or the second terminal, and the information related to PSFCH opportunities transmitted or scheduled to be transmitted or received by the own terminal. A control unit that selects a resource from some of the resources in the resource selection window based on at least one of them.
A terminal having a transmitter that transmits data to the second terminal using the selected resource.
Claim 1 that the information relating to the PSFCH opportunity received from the other terminal includes at least one of the information relating to the PSFCH opportunity received from the first terminal and the information relating to the PSFCH opportunity received from the second terminal. Described terminal.
Information indicating a PSFCH opportunity corresponding to a signal received by the second terminal, information indicating a resource based on a time resource allocation field included in control information in the signal received by the second terminal, the second terminal. Information indicating the PSFCH opportunity corresponding to the resource based on the time resource allocation field included in the control information in the signal received by the terminal, the resource based on the resource reservation cycle field included in the control information in the signal received by the second terminal. Information indicating the PSFCH opportunity corresponding to the resource based on the resource reservation cycle field included in the control information in the signal received by the second terminal, and the resource selected for transmission by the second terminal. Further having a receiving unit that receives at least one of the information shown and the information indicating the PSFCH opportunity corresponding to the resource selected for transmission by the second terminal from the second terminal via signaling. The terminal according to claim 2.
In the PSFCH opportunity corresponding to the part of the resource, the second terminal can transmit the PSFCH corresponding to the data to be transmitted to the second terminal, and the own terminal can receive the PSFCH. The terminal according to claim 1, which is possible.
When the part of the resources does not exceed a predetermined ratio of the resource selection window, the control unit changes the threshold value for determining RSRP (Reference signal received power), and again the threshold value for the resource selection window. 4. The terminal according to claim 4, which performs an operation of excluding resources based on the above.
Of the information related to PSFCH (Physical Sidelink Feedback Channel) opportunities received from other terminals including at least either the first terminal or the second terminal, and the information related to PSFCH opportunities transmitted or scheduled to be transmitted or received by the own terminal. A control procedure for selecting a resource from some of the resources in the resource selection window, based on at least one of them.
A communication method in which a terminal executes a transmission procedure for transmitting data to the second terminal using the selected resource.