WO2021205611A1 - Dispositif, procédé et système de communication - Google Patents

Dispositif, procédé et système de communication Download PDF

Info

Publication number
WO2021205611A1
WO2021205611A1 PCT/JP2020/016009 JP2020016009W WO2021205611A1 WO 2021205611 A1 WO2021205611 A1 WO 2021205611A1 JP 2020016009 W JP2020016009 W JP 2020016009W WO 2021205611 A1 WO2021205611 A1 WO 2021205611A1
Authority
WO
WIPO (PCT)
Prior art keywords
resource
communication device
communication
resource selection
data
Prior art date
Application number
PCT/JP2020/016009
Other languages
English (en)
Japanese (ja)
Inventor
フィテン チェン
剛史 下村
紅陽 陳
青木　信久
ジヤンミン ウー
Original Assignee
富士通株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 富士通株式会社 filed Critical 富士通株式会社
Priority to PCT/JP2020/016009 priority Critical patent/WO2021205611A1/fr
Publication of WO2021205611A1 publication Critical patent/WO2021205611A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W28/00—Network traffic management; Network resource management
    • H04W28/02—Traffic management, e.g. flow control or congestion control
    • H04W28/04—Error control
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/04—Wireless resource allocation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W92/00—Interfaces specially adapted for wireless communication networks
    • H04W92/16—Interfaces between hierarchically similar devices
    • H04W92/18—Interfaces between hierarchically similar devices between terminal devices

Definitions

  • the present invention relates to a communication device, a communication method, and a communication system.
  • V2X Vehicle to Everything
  • V2X is V2V (Vehicle to Vehicle) that communicates between automobiles
  • V2P Vehicle to Pedestrian
  • V2I Vehicle to Infrastructure
  • V2N Vehicle to Network
  • a feedback channel (PSFCH: Physical Sidelink Feedback CHannel) has been introduced in order to improve the quality of the side link.
  • Feedback channels are used to request data retransmissions.
  • the source terminal transmits a V2X signal and the destination terminal fails to receive / decode the V2X signal.
  • the destination terminal uses the feedback channel to transmit a NACK signal indicating reception failure.
  • the source terminal receives the NACK via the feedback channel, it retransmits the V2X signal.
  • a wireless communication method for appropriately receiving downlink data and transmitting HARQ-ACK has been proposed (for example, Patent Document 2).
  • 3GPP TS 22.186 V16.2.0 (2019-06) 3GPP TS 36.211 V16.0.0 (2019-12) 3GPP TS 36.212 V16.0.0 (2019-12) 3GPP TS 36.213 V16.0.0 (2019-12) 3GPP TS 36.300 V16.0.0 (2019-12) 3GPP TS 36.321 V15.8.0 (2019-12) 3GPP TS 36.322 V15.3.0 (2019-09) 3GPP TS 36.323 V15.5.0 (2019-12) 3GPP TS 36.331 V15.8.0 (2019-12) 3GPP TS 36.413 V16.0.0 (2019-12) 3GPP TS 36.423 V16.0.0 (2019-12) 3GPP TS 36.425 V15.0.0 (2018-06) 3GPP TS 37.340 V16.0.0 (2019-12) 3GPP TS 38.201 V16.0.0 (2019-12) 3GPP TS 38.202 V16.0.0 (2019-12) 3GPP TS 38.211 V16
  • the source terminal performs the following operation after receiving an ACK / NACK signal from the destination terminal. For example, when the source terminal receives the NACK signal from the destination terminal, it retransmits the V2X data.
  • the range in which resources for data transmission for satisfying the delay can be selected may be limited. Moreover, the selectable resource range may be further limited, for example, in order to reduce power consumption.
  • the initial transmission and the corresponding retransmission are preferably separated at regular time intervals for the transmission / reception of the ACK / NACK signal and the preparation process for the retransmission.
  • the resource for retransmission is set after the resource for initial transmission. Therefore, the resource for retransmission is selected from a limited range within the selectable resource range. Therefore, the source terminal may not be able to acquire the resource for retransmission.
  • An object relating to one aspect of the present invention is to improve communication quality in a D2D communication system that supports a feedback retransmission procedure.
  • the communication device supports D2D (Device-to-Device) communication.
  • This communication device includes a resource selection area determination unit that determines a first resource selection area and a second resource selection area that is set at a distance of a predetermined interval or more from the first resource selection area, and the first resource selection unit.
  • a resource selection unit that selects a resource for transmitting D2D data from at least one of the area or the second resource selection area, and a wireless transmission unit that transmits D2D data using the resource selected by the resource selection unit.
  • the communication quality is improved in the D2D communication system that supports the retransmission procedure by feedback.
  • the 3) which shows the example of the arrangement of the resource selection area. It is a figure (the 1) which shows the example of the minimum HARQ round trip time. It is a figure (the 2) which shows the example of the minimum HARQ round trip time. It is a figure which shows the example of the table for searching the minimum HARQ round trip time. It is a flowchart which shows an example of the communication method which concerns on embodiment of this invention. It is a flowchart which shows an example of the process which sets a plurality of subsets in a selection window. It is a figure which shows the example of the procedure of making a gap between a subset.
  • FIG. 1 shows an example of a wireless communication system according to an embodiment of the present invention.
  • the wireless communication system 100 includes a base station 1 and a plurality of communication devices 2.
  • the base station 1 controls the cellular communication (uplink / downlink communication via the Uu interface) of the communication device 2. That is, the base station 1 receives the uplink signal (control signal and data signal) from the communication device 2. Further, the base station 1 transmits a downlink signal (control signal and data signal) to the communication device 2.
  • the communication device 2 can communicate with another communication device via the base station 1. Further, the communication device 2 can also communicate with another communication device without going through the base station 1. That is, the communication device 2 supports D2D (Device-to-Device) communication. D2D communication transmits signals via, for example, a PC5 interface. Note that D2D communication is sometimes called "side link communication". Further, the communication device 2 may be referred to as a "UE (User Equipment)".
  • UE User Equipment
  • the communication device 2 When transmitting data by D2D communication, the communication device 2 determines a resource for transmitting the data. At this time, the communication device 2 detects a resource reserved by another communication device in a resource (that is, a resource pool) preset for D2D communication. Then, the communication device 2 determines a free resource based on the resource reservation information and the interference level measured for a certain period of time, selects a resource from the determined free resources, and transmits data. In the following description, the process of detecting a resource reserved by another communication device in the resource pool for D2D communication may be referred to as "sensing".
  • FIG. 2 shows an example of a method of determining a resource based on sensing.
  • a resource (re) selection trigger is generated in the subframe n.
  • the resource (re) selection trigger corresponds to, for example, an instruction to determine a resource for transmitting data generated by an application implemented in the communication device 2.
  • the communication device 2 sets a selection window and a sensing window for the resource (re) selection trigger.
  • the selection window represents the range of resources that can be selected. That is, the communication device 2 can select a resource for transmitting data from the resources in the selection window.
  • a resource (re) selection trigger is generated in subframe n
  • the range of the selection window is subframe "n + T1, n + T2".
  • the range of the parameters T1 and T2 is set in advance, for example. Alternatively, the range of the parameters T1 and T2 is notified from the base station 1.
  • the communication device 2 determines the parameters T1 and T2 within a given range. The determined parameter T2 needs to meet the delay requirement.
  • the sensing window represents the range in which the communication device 2 performs sensing. That is, the communication device 2 senses each resource in the sensing window.
  • the communication device 2 senses, for example, 1000 subframes immediately before the resource (re) selection trigger. In this case, when it is predicted that a resource (re) selection trigger will be generated in subframe n, the range of the sensing window is subframe "n-1000, n-1".
  • the communication device 2 decodes PSCCH (Physical Sidelink Control Channel), which is a control channel transmitted in the sensing window, and measures the received power of PSCH (Physical Sidelink Shared Channel), which is the corresponding data channel. do.
  • PSCCH Physical Sidelink Control Channel
  • PSCH Physical Sidelink Shared Channel
  • SCI Sidelink Control Information
  • PSSCH Physical Sidelink Shared Channel
  • transmission resource is mapped to the PSCCH resource.
  • RSRP Reference Signal Received Power
  • RSSI Receiveived Signal Strength Indicator
  • the control channel (PSCCH: Physical Sidelink Control Channel) and the data channel (PSSCH: Physical Sidelink Shared Channle) are multiplexed by TDM (Time Division Multiplexing) or FDM (Frequency Division Multiplexing). Further, in order to improve the channel quality of the side link, a feedback channel (PSFCH: Physical Sidelink Feedback Channel) has been introduced.
  • PSCCH Physical Sidelink Control Channel
  • PSSCH Physical Sidelink Shared Channle
  • TDM Time Division Multiplexing
  • FDM Frequency Division Multiplexing
  • some of the resources in the selection window are reserved by other communication devices (UE1 and UE2).
  • the communication device 2 excludes the reserved resources from the resources in the selection window and the received power is higher than the predetermined threshold value, and determines the resource for transmitting data from the remaining resources. do.
  • the sensing shown in FIG. 2 is described in Release 14 of 3GPP.
  • FIG. 3 shows another example of how to determine resources based on sensing.
  • the D2D communication transmits packets at a predetermined cycle.
  • packets are transmitted at intervals of k ⁇ 100 msec.
  • k is not particularly limited, but in this example, it is 1, 2, 5, or 10.
  • the communication device 2 sets the selection window and the sensing window corresponding to the resource (re) selection trigger, as in the case shown in FIG.
  • the communication device 2 sets a selection candidate slot set in the selection window.
  • the previous transmission should have been performed at a time dating back k ⁇ 100 msec from the selection candidate slot set. Therefore, if sensing is performed on the resource k ⁇ 100 msec before the selection candidate slot set, the communication device 2 has another resource in the selection candidate slot set when the resource (re) selection trigger is generated. It can be determined whether or not the reservation is made by the periodic traffic of the communication device.
  • the communication device 2 sets a sensing section corresponding to the selection candidate slot set in the sensing window. Specifically, as shown in FIG. 3, the sensing section is set k ⁇ 100 msec before the selection candidate slot set as a reference. The length of each sensing interval is the same as the selection candidate slot set. That is, each sensing section is composed of Y slots.
  • the communication device 2 When the resource (re) selection trigger is generated in the slot m, the communication device 2 performs sensing in the four sensing sections shown in FIG. In this case, the communication device 2 receives the control signals (eg, SCI) transmitted from the UE 1 and the UE 2, respectively, so that the periodic traffic of the UE 1 and the UE 2 reserves a predetermined resource in the selection candidate slot set. Is detected. Further, the communication device 2 measures the received power of the PSCH corresponding to the control signal. Then, the communication device 2 excludes the resources reserved by the UE1 / UE2 from the resources in the selection candidate slot set and whose received power is higher than the predetermined threshold value, and transmits data from the remaining resources. Determine the resources for.
  • the sensing shown in FIG. 3 is also described in Release 14 of 3GPP.
  • HARQ hybrid automatic repeat request
  • -ACK / NACK feedback is supported in NR-V2X. That is, when the source device transmits V2X data, the destination device transmits a feedback signal indicating whether or not the data reception is successful. Then, when the source device receives the feedback signal (that is, the NACK signal) indicating that the data reception has failed, the data is retransmitted.
  • the feedback signal is transmitted via PSFCH (Physical Sidelink Feedback Channel).
  • FIG. 4 shows an example of the arrangement of feedback channels.
  • the feedback channel ie, PSFCH
  • PSFCH is set at a predetermined cycle.
  • the feedback channel is set every 1 slot, every 2 slots, or every 4 slots.
  • the feedback channel is represented by a shaded area.
  • the slot is composed of 14 symbols in this embodiment.
  • the period in which the feedback channel is set is represented by the parameter N in this example.
  • the parameter N is set in advance for each resource pool in each communication device 2, for example.
  • the base station 1 notifies the communication device 2 of the parameter N.
  • the base station 1 notifies the communication device 2 of the parameter N for each resource pool by using PDCCH (Physical Downlink Control Channel) or RRC (Radio Resource Control).
  • PDCCH Physical Downlink Control Channel
  • RRC Radio Resource Control
  • FIG. 5 shows an example of the transmission timing of the feedback signal in HARQ feedback.
  • N 2. That is, a feedback channel is set every two slots.
  • the communication device 2 When the communication device 2 receives the V2X data via the PSCH (Physical Sidelink Shared Channel), the communication device 2 transmits a feedback signal indicating whether or not the data reception was successful to the V2X data source device.
  • the transmission timing of the feedback signal is defined by the parameter K.
  • the parameter K represents the minimum interval between PSCH reception and the corresponding HARQ feedback.
  • the parameter K is represented by the number of slots.
  • the communication device 2 determines the feedback timing for transmitting the feedback signal so that the interval between the PSCH reception and the corresponding HARQ feedback is K slot or more. ..
  • the parameter K that indicates the feedback timing is 2 or 3 in this embodiment. Then, the parameter K is set in advance in each communication device 2, for example. Alternatively, the base station 1 notifies the communication device 2 of the parameter K. In this case, the base station 1 notifies the communication device 2 of the parameter K by using PDCCH, RRC, or the like.
  • the communication device 2 receives V2X data in slot n + 1 via PSCH.
  • K 2.
  • the communication device 2 can transmit the hoodback signal in the slot two or more slots after the slot n + 1. Therefore, the communication device 2 transmits the hoodback signal in the slot n + 3.
  • the communication device 2 can transmit a hoodback signal in a slot two or more slots after slot n.
  • the hoodback channel is not set in slot n + 2. Therefore, in this case, the communication device 2 transmits the hoodback signal in the slot n + 3.
  • the feedback channel is set at a predetermined cycle. Further, the communication device 2 determines whether or not to perform retransmission after receiving the footback signal. Therefore, the resources that can be selected by the communication device 2 for retransmission are reduced in the system that performs HARQ feedback as compared with the system that does not perform HARQ feedback. As a result, the probability of packet collision may increase.
  • slots S1 to S9 are set as selection candidate slot sets.
  • This candidate slot set includes four subchannels in the frequency domain.
  • one resource is composed of one slot and one subchannel.
  • the selection candidate slot set is composed of 36 resources.
  • the communication device 2 cannot use the resources reserved by other communication devices even if the resources are in the selection candidate slot set. Therefore, the communication device 2 extracts a predetermined number of resources that are not reserved by other communication devices from the resources in the selection candidate slot set. In this embodiment, it is assumed that 20% or more of the resources in the selection candidate slot set are extracted. As an example, it is assumed that the eight resources R1 to R8 shown in FIG. 6 have been extracted.
  • the communication device 2 sets the above-mentioned selection candidate slot set and extracts resources R1 to R8 from the selection candidate slot set. Further, as shown in FIG. 7A, the communication device 2 shall transmit V2X data by using the resource R1.
  • the parameter K representing the feedback timing is 3.
  • the destination terminal of the V2X data transmits the feedback signal via the feedback channel set in the slot S4. That is, the communication device 2 receives the feedback signal via the feedback channel set in the slot S4.
  • the communication device 2 can retransmit the V2X data after receiving the feedback signal. Therefore, when the V2X data is transmitted using the resource R1, the communication device 2 can retransmit the V2X data using any of the resources R5 to R8.
  • the communication device 2 transmits V2X data using the resource R2.
  • the destination terminal of the V2X data cannot transmit the feedback signal via the feedback channel set in the slot S4, and transmits the feedback signal via the feedback channel set in the slot S8. That is, the communication device 2 receives the feedback signal via the feedback channel set in the slot S8. Therefore, when the V2X data is transmitted using the resource R2, the communication device 2 can retransmit the V2X data using the resource R8.
  • the communication device 2 transmits V2X data using the resource R5.
  • the destination terminal of the V2X data transmits the feedback signal via the feedback channel set in the slot S12. That is, the communication device 2 receives the feedback signal via the feedback channel set in the slot S12. Therefore, when the V2X data is transmitted using the resource R5, the communication device 2 cannot retransmit using the resources in the selection candidate slot set.
  • the communication device 2 performs a new resource selection process in order to perform retransmission.
  • the resource selection process sets the selection candidate slot set and determines the resource based on the sensing results in the corresponding sensing interval. However, when a new resource selection process is performed, the power consumption of the communication device 2 and the delay of data transmission increase.
  • the resources that can be selected for retransmission are reduced.
  • a case where HARQ feedback is performed and a case where HARQ feedback is not performed are compared.
  • the communication device 2 can select a resource for retransmission from the resources R2 to R8. That is, the number of resources that can be selected for retransmission is 7. Further, when the resource R2 is used for the first transmission, the communication device 2 can select a resource for retransmission from the resources R4 to R8. That is, the number of resources that can be selected for retransmission is five. Similarly, when the first transmission is performed using the resources R3, R4, R5, R6, R7, and R8, the number of resources that can be selected for retransmission is 5, 4, 3, 2, 1, respectively. , 0. Therefore, the total number of resource combinations that can realize initial transmission and retransmission in the selection candidate slot set shown in FIG. 6 is 27.
  • HARQ feedback shall be performed in the selection candidate slot set shown in FIG.
  • the communication device 2 can select a resource for retransmission from the resources R5 to R8 as shown in FIG. 7A. That is, the number of resources that can be selected for retransmission is four.
  • the communication device 2 can select the resource 8 for the retransmission. That is, the number of resources that can be selected for retransmission is 1.
  • the first transmission is performed using the resource R3 or the resource R4
  • the number of resources that can be selected for retransmission is 1.
  • the communication device 2 cannot perform the retransmission in the selection candidate slot set.
  • the resources R5 to R8 are used for the first transmission, the communication device 2 cannot perform the retransmission in the selection candidate slot set. Therefore, the total number of resource combinations that can realize initial transmission and retransmission in the selection candidate slot set shown in FIG. 6 is 7.
  • the communication device has a function of increasing the resources that can be selected for retransmission in the selection candidate slot set in the communication system that performs HARQ feedback.
  • ⁇ Embodiment> 8 to 10 show an example of arranging the resource selection area.
  • the selection window consists of 20 slots.
  • the selection candidate slot set also includes nine slots.
  • the feedback channel PSFCH is set every 4 slots.
  • the selection candidate slot set includes multiple Cebu sets.
  • the selection candidate slot set is composed of two subsets.
  • Each subset is an example of a resource selection area. That is, the communication device 2 can select a resource for transmitting or retransmitting V2X data from each subset.
  • the gap is an example of a resource non-selected area. That is, the communication device 2 does not select resources in the gap to transmit or retransmit V2X data.
  • the width of the gap is determined based on the HARQ round trip time. Specifically, the gap G is determined by the equation (1). G ⁇ min ( TRTT ) -1 ... (1)
  • Min ( TRTT ) represents the minimum value of the HARQ round trip time.
  • the HARQ round trip time represents the time from transmission of V2X data to retransmission corresponding to the transmission in the HARQ feedback procedure.
  • the HARQ round trip time represents the time from transmission of V2X data to retransmission corresponding to the transmission in the HARQ feedback procedure.
  • the minimum HARQ round trip time is 4 slots.
  • the retransmission can be performed after the feedback channel set in the slot S8. That is, the retransmission is performed in slot S9 in the earliest case.
  • the minimum HARQ round trip time is 7 slots.
  • the "-1" in the above calculation formula represents “1 slot” and is provided to obtain a "gap” between subsets.
  • the time between the last slot of the subsystem and the first slot of the next subset corresponds to the minimum round trip time.
  • the selection candidate slot set is composed of three subsets.
  • the number of subsets that can be set in the selection window is not particularly limited.
  • each subset is composed of a plurality of non-consecutive slots.
  • the communication device 2 can select only the resources represented by the diagonal lines. For example, the communication device 2 selects a resource from the first, second, and fourth slots when performing the first transmission.
  • the communication device 2 may be set to retransmit once for the first transmission, or may be set to retransmit twice for the first transmission. good. That is, the following retransmission patterns can be set.
  • N represents the period in which the feedback channel is set, which is "4" in this example.
  • K represents the minimum interval between PSCH reception and the corresponding HARQ feedback, which is "3" in FIG. 11 and "2" in FIG.
  • Np represents the feedback processing time.
  • Np is represented by the number of slots. In this example, Np is "0". That is, the time required for feedback processing is shorter than one symbol time.
  • the transmission timing represents a slot in which V2X data is transmitted. In FIGS. 11 to 12, the transmission timing is represented by "Tx".
  • a slot number that identifies each slot in the resource pool is given.
  • slot numbers "0" to "11” are assigned to the 12 slots.
  • the slot in which V2X data is transmitted may be referred to as a “transmission slot”.
  • a slot in which a feedback channel is set is sometimes called a "feedback slot”.
  • slots 3, 7, and 11 are feedback slots.
  • the feedback slot when the number of slots from the transmission slot to the first feedback slot (hereinafter referred to as the first feedback slot) set after the transmission slot is K or more, the feedback slot is used.
  • the feedback signal comes back. That is, in Case 1 shown in FIG. 11 and Cases 1 and 2 shown in FIG. 12, the feedback signal is returned in the first feedback slot.
  • the first feedback slot At the earliest, retransmissions occur in the slot following the first feedback slot.
  • the feedback signal is returned in the second feedback slot from the transmission slot. That is, in cases 2 to 4 shown in FIG. 11 and cases 3 to 4 shown in FIG. 12, the feedback signal is returned in the second feedback slot. Therefore, in these cases, the retransmission is performed in the slot next to the second feedback slot at the earliest.
  • the minimum HARQ round trip time can be determined based on the number of slots from the transmission slot to the first feedback slot. It is also possible to calculate the minimum HARQ round trip time using the following equation based on the parameters described above.
  • "() modN" represents an operator that divides the numerical value in parentheses by N to calculate the remainder.
  • N represents the slot number of the transmission slot in the resource pool.
  • the minimum HARQ round trip time represents the minimum value of the time required from transmission to retransmission corresponding to the transmission in the HARQ feedback system. Therefore, no retransmission is performed during the period from the transmission slot to the "minimum HARQ round trip time-1 slot".
  • the width of the gap between the subsets shown in FIGS. 8 to 10 is set to "minimum HARQ round trip time-1 slot" or more. Then, immediately after the subset for selecting the transmission resource, a gap interval in which no retransmission occurs is provided. That is, the slots constituting the selection candidate slot set are not arranged in the section where retransmission is not performed. Therefore, when the number of slots used as the selection candidate slot set is determined, the slots constituting the selection candidate slot set can be arranged in the section where retransmission can be performed.
  • the minimum HARQ round trip time can be calculated from the feedback channel period N, feedback timing K, and processing time Np.
  • N and K are set in advance for each resource pool, or are notified from the base station 1 by RRC signaling.
  • the processing time Np is set in advance based on the capability of the communication device 2, or is notified from the base station 1 by RRC signaling.
  • the minimum HARQ round trip time is determined for the subset set in the selection window.
  • the table shown in FIG. 13 (a) or FIG. 13 (b) is prepared. The table is set in the communication device 2 in advance, or is notified from the base station 1 by RRC signaling. Then, the communication device 2 acquires the minimum HARQ round trip time by searching the table. At this time, "n" represents the slot number of the last slot of the subset set before the gap.
  • FIG. 14 is a flowchart showing an example of a communication method according to the embodiment of the present invention. The processing of this flowchart is executed, for example, when a resource (re) selection trigger is generated in the communication device 2, or periodically.
  • the communication device 2 sets a selection window corresponding to the resource (re) selection trigger.
  • the parameters for setting the selection window (T1, T2, etc. in FIG. 3) are predetermined or notified from the base station 1.
  • the communication device 2 sets a selection candidate slot set in the selection window.
  • the number of slots included in the selection candidate slot set is predetermined or notified by the base station 1.
  • the selection candidate slot set includes a plurality of subsets as shown in FIGS. 8 to 10. That is, in S2, a plurality of subsets are set in the selection window. Each subset is an example of a resource selection area. How to set up multiple subsets will be described in detail later.
  • the communication device 2 sets a sensing section.
  • the sensing section is not particularly limited, but is set by the method described with reference to FIG. 3, for example.
  • the communication device 2 performs sensing in the sensing section and analyzes the result. Specifically, the control information (for example, SCI) is decoded for each resource in the sensing section, and the received power (for example, RSRP of PSCCH or RSRP or RSSI of PSCH) is calculated. The result of sensing is saved in memory.
  • the control information for example, SCI
  • the received power for example, RSRP of PSCCH or RSRP or RSSI of PSCH
  • the communication device 2 extracts a resource reserved by another communication device and whose received power is larger than the threshold value, based on the sensing result.
  • the communication device here, the communication device Z
  • the communication device notifies the surrounding devices of the content of the reservation by using SCI.
  • this notification reaches each communication device located around the communication device Z. Therefore, the communication device 2 can detect the resource reservation by sensing. Then, the communication device 2 excludes the resources extracted based on the reserved and received power from the resources in the selection candidate slot set.
  • the communication device 2 determines whether or not a predetermined amount or more of resources remain in each subset.
  • the predetermined amount is, for example, 20 percent of the total amount of resources in the initial state of the subset. Then, when the amount of the remaining resources is less than the predetermined amount, the communication device 2 increases the threshold value in S8. At this time, the threshold value is incremented by, for example, 3 dB. After that, the processing of the communication device 2 returns to S5. That is, the processes S6 to S9 are repeatedly executed until the amount of resources remaining in the subset becomes a predetermined amount or more. Then, when the amount of resources remaining in the subset exceeds a predetermined amount, the processing of the communication device 2 proceeds to S9.
  • the communication device 2 selects a resource for transmitting data from the resources remaining in each subset. Then, the communication device 2 transmits data using the selected resource.
  • FIG. 15 is a flowchart showing an example of a process of setting a plurality of subsets in the selection window.
  • the number Y of slots extracted as the selection candidate slot set in the selection window is specified in advance.
  • the processing of this flowchart corresponds to S2 shown in FIG. That is, it is assumed that the selection window is set before the processing of this flowchart is executed.
  • the communication device 2 initializes the variable i to "1".
  • the variable i identifies the subset.
  • the communication device 2 selects consecutive Ni slots constituting the subset i in the selection window, as shown in FIG. 16A.
  • the communication device 2 can select consecutive Ni slots at arbitrary positions in the selection window.
  • the communication device 2 sets the gap X for the first slot of the subset i, and excludes the slots belonging to the gap X from the selection target slots.
  • the first slot of the subset i also belongs to the gap X, but the first slot of the subset i remains selected and is not excluded. In the example shown in FIG. 16A, four slots are excluded. The method of determining the width of the gap X will be described later.
  • the communication device 2 sets the gap Y for the last slot of the subset i, and excludes the slots belonging to the gap Y from the selection target slots.
  • the last slot of the subset i also belongs to the gap Y, but the first slot of the subset i remains selected and is not excluded.
  • three slots are excluded.
  • the width of the gap Y is the minimum HARQ round trip time described with reference to FIGS. 11 to 13.
  • the communication device 2 increments the variable i.
  • the communication device 2 selects consecutive Ni slots constituting the next subset i in the selection window. At this time, the communication device 2 does not select the slots excluded in S13 to S14. Further, the communication device 2 does not select the previously selected slot.
  • the communication device 2 compares the total number of slots ⁇ Ni selected as the subset i with the predetermined number Ntotal. As described above, Ntotal represents the number of slots extracted as the selection candidate slot set in the selection window. Then, when ⁇ Ni is smaller than Ntotal, the communication device 2 returns the slots excluded in S13 to S14 to a selectable state in S18. After that, the processing of the communication device 2 returns to S13. That is, the processes S13 to S18 are repeatedly executed until ⁇ Ni becomes Ntotal or more. Then, when ⁇ Ni becomes Ntotal or more, the process of setting the subset ends.
  • FIG. 17 is a flowchart showing another example of the process of setting a plurality of subsets in the selection window.
  • each subset contains non-contiguous slots, as shown in FIG. 16 (b).
  • the procedure for setting the subset in the selection window is almost the same in FIGS. 15 and 17.
  • the communication device 2 selects Ni non-contiguous slots as the subset i.
  • the interval between the slots selected as the subset i is shorter than the minimum HARQ round trip time.
  • the communication device 2 excludes the slots located between the slots selected as the subset i in S21 from the selection target slots.
  • the width of the gap X may be obtained by referring to the table shown in FIG. 18 (a) or FIG. 18 (b).
  • the table is set in the communication device 2 in advance, or is notified from the base station 1 by RRC signaling. Then, the communication device 2 acquires the width of the gap X by searching the table. At this time, "n" represents the slot number of the first slot of each subset.
  • a subset is set using gap X and gap Y, but the invention is not limited to this method.
  • a subset is set using "minimum HARQ round trip time TRTT -1".
  • the K representing the minimum interval between PSCH reception and the corresponding HARQ feedback is 3.
  • the HARQ processing time Np is 0. That is, the time required for HARQ processing is shorter than one symbol time.
  • the number Y of slots selected as the selection candidate slot set from the selection window is 9.
  • subset 1 is set.
  • Subset 1 is set at the top of the selection window, but is not particularly limited. Also, in this example, subset 1 includes three slots.
  • Subset 2 is set to have a " TRTT -1" slot gap between subsets 1 and 2, as shown in FIG. 19 (c).
  • Subset 3 is set to have a " TRTT -1" slot gap between subsets 2 and 3, as shown in FIG. 19 (d).
  • subset 3 includes three slots. Then, the total number of slots included in the subsets 1 to 9 is "9", which is Y or more, so that the process of setting the subset ends.
  • Case 1 No HARQ feedback in the selection candidate slot set shown in FIG. 6: HARQ feedback is performed in the selection candidate slot set shown in FIG. 6: Case 3: Subsets 1 and 2 shown in FIG. 20 (a). Case 4: Subsets 1 to 3 shown in FIG. 20 (b)
  • the total number of combinations of Case 1 and Case 2 is 27 and 7, respectively, as described with reference to FIGS. 6 to 7. That is, in the selection candidate slot set shown in FIG. 6, when HARQ feedback is performed, the number of selectable resources decreases and the probability of packet collision increases.
  • subsets 1 and 2 are set.
  • 20% or more of the resources are selected as selectable resources.
  • resources R1 to R4 are selected in subset 1
  • resources R5 to R8 are selected in subset 2.
  • the time from the last slot of Subset 1 to the first slot of Subset 2 corresponds to the minimum HARQ round trip time.
  • the corresponding retransmission can be performed in the subset 2.
  • the communication device 2 receives the feedback signal in the slot S4.
  • the communication device 2 can select a resource for retransmission from the selectable resources in slots S5 and thereafter. That is, the communication device 2 can select any one of the resources R5 to R8 for retransmission. Therefore, when the first transmission is performed using the resource R1, the number of combinations of resources that can realize the first transmission and the retransmission is four. Similarly, when the first transmission is performed using the resource R2, the number of combinations of resources that can realize the first transmission and the retransmission is four.
  • the communication device 2 When the first transmission is performed using the resource R3, the communication device 2 receives the feedback signal in the slot S8. In this case, the communication device 2 can select a resource for retransmission from the selectable resources in slots S9 and thereafter. That is, the communication device 2 can select any one of the resources R5 to R8 for retransmission. Therefore, even when the first transmission is performed using the resource R2, the number of combinations of resources that can realize the first transmission and the retransmission is four. Similarly, when the first transmission is performed using the resource R4, the number of combinations of resources that can realize the first transmission and the retransmission is four. Therefore, in Case 3, the total number of resource combinations that can realize the initial transmission and the retransmission is 16 as shown in FIG.
  • subsets 1 to 3 are set.
  • 20% or more of the resources are selected as selectable resources.
  • resources R1 to R3 are selected in subset 1
  • resources R4 to R6 are selected in subset 2
  • resources R7 to R9 are selected in subset 3.
  • the time from the last slot of subset 1 to the first slot of subset 2 corresponds to the minimum HARQ round trip time
  • the time from the last slot of subset 2 to the first slot of subset 3 is also the minimum HARQ round trip time.
  • the corresponding retransmission can be performed in the subset 2 or the subset 3. That is, when the first transmission is performed using the resource R1, it is possible to perform the retransmission using any of the resources R4 to R9. The same applies when the first transmission is performed using the resources R2 and R3. Therefore, when the first transmission is performed in the subset 1, the total number of resource combinations that can realize the first transmission and the retransmission is 18.
  • the corresponding retransmission can be performed in the subset 3. That is, when the first transmission is performed using the resource R4, it is possible to perform the retransmission using any of the resources R7 to R9. The same applies when the first transmission is performed using the resources R5 and R6. Therefore, when the first transmission is performed in the subset 2, the total number of resource combinations that can realize the first transmission and the retransmission is nine. Therefore, in Case 4, the total number of resource combinations that can realize the initial transmission and the retransmission is 27, as shown in FIG.
  • the total number of combinations of resources capable of realizing initial transmission and retransmission is larger than that in case 2. That is, by dividing the selection candidate slot set into a plurality of subsets, the probability that a plurality of communication devices in the communication system select the same resource is reduced. As a result, the probability of packet collisions is low.
  • the communication method according to the embodiment of the present invention is premised on the partial sensing shown in FIG. That is, the communication method according to the embodiment of the present invention can suppress packet collision while reducing power consumption and improving reliability by HARQ feedback.
  • FIG. 22 shows an example of the configuration of the base station 1.
  • the base station 1 is, for example, a next-generation base station apparatus (gNB: Next generation NodeB). Then, as shown in FIG. 22, the base station 1 includes a control unit 11, a storage unit 12, a network interface 13, a radio transmission unit 14, and a radio reception unit 15.
  • the base station 1 may have other circuits or functions not shown in FIG. 22.
  • the control unit 11 controls the cellular communication provided by the base station 1. Further, the control unit 11 may determine parameters for D2D communication (that is, side link communication) performed by the communication device 2. For example, the control unit 11 may determine parameters T1 and T2 representing the arrangement of the selection window shown in FIG. 5, parameter Y representing the number of slots in the selection candidate slot set, and the like. Further, the control unit 11 may determine a parameter N representing the period of the feedback channel, a parameter K representing the minimum interval between the PSCH reception and the corresponding HARQ feedback, and the like. The determined parameter is notified to the communication device 2 by, for example, PDCCH or RRC.
  • the control unit 11 is realized by the processor in this embodiment. However, some of the functions of the control unit 11 may be realized by a hardware circuit.
  • the storage unit 12 stores a software program executed by the processor. Further, the storage unit 12 stores data and information necessary for controlling the operation of the base station 1.
  • the storage unit 12 is realized by, for example, a semiconductor memory.
  • the network interface 13 provides an interface for connecting to the core network. That is, the base station 1 can be connected to another base station 1 or a network management system that controls the base station 1 via the network interface 13.
  • the wireless transmission unit 14 transmits a wireless signal for cellular communication according to an instruction given from the control unit 11. That is, the wireless transmission unit 14 transmits a downlink signal to the communication device 2 located in the cell.
  • the radio receiving unit 15 receives the radio signal of cellular communication according to the instruction given from the control unit 11. That is, the wireless receiving unit 15 receives the uplink signal transmitted from the communication device 2 located in the cell.
  • cellular communication is provided, for example, using the 2.4 GHz band and / or the 4 GHz band.
  • FIG. 23 shows an example of the configuration of the communication device 2.
  • the communication device 2 supports cellular communication and D2D communication. Note that D2D communication is realized by using a frequency band different from that of cellular communication. For example, D2D communication is provided using the 6 GHz band. However, the D2D communication may share the same frequency band as the uplink of the cellular communication.
  • the communication device 2 includes a control unit 21, a storage unit 22, a wireless transmission unit 23, a wireless reception unit 24, a wireless transmission unit 25, and a wireless reception unit 26.
  • the communication device 2 may have other circuits or functions not shown in FIG.
  • the control unit 21 controls the cellular communication and the D2D communication provided by the communication device 2.
  • the control unit 21 is realized by the processor in this embodiment.
  • the control unit 21 provides a function of controlling cellular communication and D2D communication by executing a software program stored in the storage unit 22.
  • the control unit 21 executes a program that describes the processing of the flowchart shown in FIG. 14 (including the processing of the flowchart shown in FIG. 15 or 17).
  • the control unit 21 executes, for example, the processing of the flowchart shown in FIG. 14 in response to the resource (re) selection trigger in the communication device 2.
  • control unit 21 provides a function of a resource area determination unit that determines a plurality of subsets as a resource selection area and a resource selection unit that selects a resource for transmitting a D2D signal from the resource selection area.
  • a part of the function of the control unit 21 may be realized by a hardware circuit.
  • the storage unit 22 stores a software program executed by the processor. Further, the storage unit 22 stores data and information necessary for controlling the operation of the communication device 2.
  • the storage unit 22 is realized by, for example, a semiconductor memory.
  • the wireless transmission unit 23 transmits a wireless signal for cellular communication according to an instruction given from the control unit 21. That is, the wireless transmission unit 23 transmits an uplink signal to the base station 1.
  • the radio receiving unit 24 receives the radio signal of cellular communication according to the instruction given from the control unit 21. That is, the wireless receiving unit 24 receives the downlink signal transmitted from the base station 1. At this time, the wireless reception unit 24 may receive parameters related to resource selection for D2D communication from the base station 1.
  • the wireless transmission unit 25 transmits a wireless signal for D2D communication according to an instruction given from the control unit 21. That is, the wireless transmission unit 25 transmits a D2D signal to another communication device by using the resource selected by the communication device 2 by itself.
  • the radio receiving unit 26 receives a radio signal for D2D communication according to an instruction given from the control unit 21. That is, the wireless receiving unit 26 receives the D2D signal transmitted from another communication device.
  • the D2D signal includes V2X data and V2X control information in this embodiment.
  • the sensing process of S4 shown in FIG. 14 is executed by the wireless receiving unit 26. That is, the wireless receiving unit 26 has a sensing function. In this case, the wireless receiving unit 26 may include a processor that executes the sensing process.
  • the wireless communication unit for cellular communication and the wireless communication unit for D2D communication are provided separately from each other, but the communication device 2 is not limited to this configuration. ..
  • the wireless communication unit for cellular communication and the wireless communication unit for D2D communication may be shared. In this case, the wireless transmission unit 25 and the wireless reception unit 26 are unnecessary.
  • the wireless transmission unit 23 transmits the cellular signal and the D2D signal
  • the wireless reception unit 24 receives the cellular signal and the D2D signal.
  • the wireless receiving unit 24 has a sensing function.
  • Base station 2 Communication device 11 Control unit 12 Storage unit 13 Network interface 14 Wireless transmission unit 15 Wireless reception unit 21 Control unit 22 Storage unit 23, 25 Wireless transmission unit 24, 26 Wireless reception unit 100 Wireless communication system

Abstract

La présente invention améliore les qualités de communication dans des systèmes de communication D2D pour prendre en charge des procédures de retransmission à l'aide de rétroactions. Un dispositif de communication selon la présente invention prend en charge des communications de dispositif à dispositif (D2D), et comprend une unité de détermination de région de sélection de ressource, une unité de sélection de ressource et une unité de transmission radio. L'unité de détermination de région de sélection de ressource détermine une première région de sélection de ressource et une seconde région de sélection de ressource qui doit être établie à distance de la première région de sélection de ressource d'un intervalle égal ou supérieur à un intervalle prédéterminé. L'unité de sélection de ressource sélectionne, à partir de la première région de sélection de ressource ou de la seconde région de sélection de ressource, une ressource pour transmettre des données D2D. L'unité de transmission radio transmet les données D2D en utilisant la ressource sélectionnée par l'unité de sélection de ressources.
PCT/JP2020/016009 2020-04-09 2020-04-09 Dispositif, procédé et système de communication WO2021205611A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2020/016009 WO2021205611A1 (fr) 2020-04-09 2020-04-09 Dispositif, procédé et système de communication

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2020/016009 WO2021205611A1 (fr) 2020-04-09 2020-04-09 Dispositif, procédé et système de communication

Publications (1)

Publication Number Publication Date
WO2021205611A1 true WO2021205611A1 (fr) 2021-10-14

Family

ID=78023255

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2020/016009 WO2021205611A1 (fr) 2020-04-09 2020-04-09 Dispositif, procédé et système de communication

Country Status (1)

Country Link
WO (1) WO2021205611A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023241436A1 (fr) * 2022-06-14 2023-12-21 维沃移动通信有限公司 Procédé et appareil de traitement de ressource, et terminal

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016076301A1 (fr) * 2014-11-14 2016-05-19 株式会社Ｎｔｔドコモ Dispositif utilisateur, procédé de commande de rétroaction et procédé de commande de retransmission
JP2018102011A (ja) * 2018-03-19 2018-06-28 ソニー株式会社 装置
WO2020031397A1 (fr) * 2018-08-07 2020-02-13 富士通株式会社 Dispositif terminal, dispositif de communication sans fil, système de communication sans fil, et procédé de communication sans fil

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016076301A1 (fr) * 2014-11-14 2016-05-19 株式会社Ｎｔｔドコモ Dispositif utilisateur, procédé de commande de rétroaction et procédé de commande de retransmission
JP2018102011A (ja) * 2018-03-19 2018-06-28 ソニー株式会社 装置
WO2020031397A1 (fr) * 2018-08-07 2020-02-13 富士通株式会社 Dispositif terminal, dispositif de communication sans fil, système de communication sans fil, et procédé de communication sans fil

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023241436A1 (fr) * 2022-06-14 2023-12-21 维沃移动通信有限公司 Procédé et appareil de traitement de ressource, et terminal

Similar Documents

Publication Publication Date Title
US11438888B2 (en) Beam configuration method and apparatus
US11206682B2 (en) Methods and devices for scheduling group uplink communication
KR102513274B1 (ko) 무선 통신 시스템에서 복합 재전송을 수행하는 방법 및 장치
RU2454006C2 (ru) Базовая станция, терминал пользователя и способ управления связью, используемый в системе мобильной связи
KR101574334B1 (ko) 복수 기지국에 의한 조인트 상향링크 데이터 처리
CN113783663B (zh) 传输信息的方法、终端设备和网络设备
CN113490286B (zh) 随机接入的方法、终端设备和网络设备
US10841068B2 (en) DL HARQ timing in TDD with 1 ms tti and reduced processing time
KR102247385B1 (ko) 전송 방법, 네트워크 장비, 및 단말 장비
US20220394560A1 (en) Method and apparatus for pre-empting a resource
JP2023501201A (ja) サイドリンクリソースのリザーブ方法及び装置
CN116368886A (zh) 用于一个时隙中多个侧链路传输机会的方法及设备
CN112586031A (zh) 无线通信方法和终端
JPWO2020031397A1 (ja) 端末装置、無線通信装置、無線通信システム及び無線通信方法
US11856612B2 (en) Method and apparatus for performing random access in wireless communication system
WO2021205611A1 (fr) Dispositif, procédé et système de communication
WO2021160375A1 (fr) Appareil et procédés de télécommunications
US20220006573A1 (en) Wireless data transmission apparatus, wireless data reception apparatus and methods
US20230261840A1 (en) Radio nodes, network nodes, circuitry, systems and methods
US11647507B2 (en) Device and method for handling physical uplink control channel collision
US20230336314A1 (en) Communications devices, network infrastructure equipment, wireless communications networks and methods
CN110603766A (zh) 确认资源的持续指示
CN115868135A (zh) 载波切换方法、装置、设备及存储介质
CN107534523B (zh) 用户设备、接入网设备及上行控制信息的发送和接收方法
CN117223309A (zh) 一种资源指示方法及装置、终端设备

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20930586

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20930586

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP