CN117440348A

CN117440348A - Method performed by user equipment and user equipment

Info

Publication number: CN117440348A
Application number: CN202210798637.4A
Authority: CN
Inventors: 赵毅男; 罗超; 刘仁茂
Original assignee: Sharp Corp
Current assignee: Sharp Corp
Priority date: 2022-07-11
Filing date: 2022-07-11
Publication date: 2024-01-23
Also published as: WO2024012390A1

Abstract

According to the present invention, there is provided a method performed by a user equipment, comprising the steps of: selecting and generating a selected sidestream communication scheduling license; and performing a transmission resource selection or reselection procedure.

Description

Method performed by user equipment and user equipment

Technical Field

The present invention relates to the field of wireless communication technology, and in particular, to a method performed by a user equipment and a corresponding user equipment.

Background

In a conventional cellular network, all communications must pass through a base station. In contrast, D2D communication (Device-to-Device communication, device-to-Device direct communication) refers to a communication method in which two user equipments directly perform communication without being forwarded by a base station or a core network. On the RAN #63 full-meeting of the third generation partnership project (3rd Generation Partnership Project,3GPP) in 2014, a study subject about the realization of near D2D communication services using LTE devices is approved (see non-patent document 1). The functions introduced by LTE Release 12 d2d include:

1) Discovery function (Discovery) between neighboring devices in an LTE network coverage scenario;

2) A direct Broadcast communication (Broadcast) function between nearby devices;

3) The higher layers support Unicast (Unicast) and multicast (Groupcast) communication functions.

In the 3gpp ran#66 group of 12 of 2014, a research project of enhanced LTE eD2D (enhanced D2D) is approved (see non-patent document 2). The main functions introduced by LTE Release 13 e d2d include:

1) D2D discovery of network-free and partial network coverage scenes;

2) Priority handling mechanism for D2D communication.

The V2X feasibility study subject by D2D communication was approved on the RAN #68 meeting of 3GPP at 6 months in 2015 based on the design of D2D communication mechanism. V2X represents Vehicle to Everything for the purpose of enabling the interaction of a vehicle with all physical information that may affect the vehicle in order to reduce incidents, alleviate traffic congestion, reduce environmental pollution and provide other information services. The application scenario of V2X mainly includes 4 aspects:

1) V2V, vehicle to Vehicle, i.e. vehicle-to-vehicle communication;

2) V2P, vehicle to Pedestrian, i.e. the vehicle sends a warning to pedestrians or non-motor vehicles;

3) V2N, vehicle to Network, i.e. the vehicle is connected to a mobile network;

4) V2I, vehicle to Infrastructure, i.e. the vehicle communicates with the road infrastructure etc.

The 3GPP divides V2X research and standardization work into 3 phases. The first stage was completed in 2016, 9, and mainly focused on V2V, and was formulated based on LTE Release 12 and Release 13 d2d (also referred to as sidelink side communication), that is, proximity communication technology (see non-patent document 3). V2X phase 1 introduces a new D2D communication interface, called PC5 interface. The PC5 interface is mainly used for solving the communication problem of the cellular Internet of vehicles in a high-speed (up to 250 km/h) and high-node-density environment. The vehicles can interact with information such as position, speed and direction through the PC5 interface, i.e. the vehicles can communicate directly with each other through the PC5 interface. In comparison with proximity communication between D2D devices, LTE Release 14 v2x introduced functions mainly include:

1) Higher density DMRS to support high speed scenarios;

2) Introducing a sub-channel (sub-channel), and enhancing a resource allocation mode;

3) A user equipment aware (sensing) mechanism with semi-persistent scheduling is introduced.

The second stage of V2X research topic falls into the LTE Release 15 research category (see non-patent document 4), and the main characteristics introduced include high-order 64QAM modulation, V2X carrier aggregation, short TTI transmission, and feasibility study of transmit diversity.

The corresponding third stage was approved based on the V2X feasibility study topic of 5G NR network technology (see non-patent document 5) at the 3gpp ran#80 corpus at 6 of 2018.

In the 5g NR v2x problem, a resource allocation method 2 (resource allocation mode 2) based on user equipment awareness (sensing) is supported, or referred to as transmission mode 2. For the resource allocation mode 2 perceived by the user equipment, the physical layer of the user equipment perceives the transmission resources in the resource pool, which means that the user equipment determines whether to exclude (include) the resources overlapping with the resources indicated by the indication information in the candidate resource set according to the received indication information in the SCI sent by other user equipment, the non-excluded resources in the candidate resource set are reported to the higher layer, and the higher layer randomly selects the resources for PSSCH/PSCCH transmission in the reported resource set.

On the whole of 3gpp ran#90e at 12 months in 2020, a standardization research topic (see non-patent document 6) based on enhancement of NR sidestream communication (NR sidelink enhancement) which has been standardized is approved. The enhancement of sidestream communication comprises the following three aspects:

1) Standardized resource allocation approaches to reduce power consumption (power save) of sidestream communication user devices, including but not limited to: based on a part of perceived resource allocation mode (partial serving), a resource allocation mode selected based on random resources;

2) The communication reliability of the resource allocation mode 2 in NR side-row communication is researched and improved, and the communication time delay of the resource allocation mode 2 is reduced;

3) Standardized sidestream communication discontinuous reception (SL Discontinuous Reception, SL DRX) mechanism. In 5G NR communication, the ue supports discontinuous reception of the PDCCH, called DRX, in time, which can effectively reduce power consumption of the communication device. Similarly, corresponding to SL DRX, discontinuous reception refers to listening for sidestream communication control information SCI (including SCI level 1 and SCI level 2) for a portion of the time in the time domain, which is referred to as the Active period (Active time).

At 3 rd month 3gpp ran#95e of 2022, a standardization research topic (see non-patent document 7) based on the evolution of NR sidestream communication (NR sidelink evolution, abbreviated as NR SL evo) that has been standardized is approved. The targets of NR SL evo include the following:

1) NR-side communication over unlicensed spectrum (unlicensed spectrum), abbreviated SL-U, is studied and standardized. The SL-U includes both resource allocation scheme 1 and resource allocation scheme 2 for NR side row communication. The research project specifically comprises:

a. in SL-U, reuse NR air interface is in channel access (channel access) technology and operation of unlicensed spectrum communication (NR unlicensed), which is simply called NR-U. Wherein the channel access technology of NR-U refers to Listen Before Talk (abbreviated as LBT) technology, that is, "listen before talk", which means that before a ue transmits, it needs to monitor the channel resources used for transmission, and if the channel is idle, it transmits; otherwise, the transmission is aborted.

b. Study of the design framework of physical channels in sidestream communications: i.e. the structure of the physical channel in existing NR sidestream communications is modified as necessary to enable SL-U.

Prior art literature

Non-patent literature

Non-patent document 1: RP-140518,Work item proposal on LTE Device to Device Proximity Services

Non-patent document 2: RP-142311,Work Item Proposal for Enhanced LTE Device to Device Proximity Services

Non-patent document 3: RP-152293,New WI proposal: support for V2V services based on LTE sidelink

Non-patent document 4: RP-170798,New WID on 3GPP V2X Phase 2

Non-patent document 5: RP-181480,New SID Proposal: studion NR V2X

Non-patent document 6: RP-202846,WID revision: NR sidelink enhancement

Non-patent document 7: RP-220300,WID revision: NR sidelink evolution

Disclosure of Invention

In order to solve at least a part of the above problems, the present invention provides a method executed by a ue and the ue, so that the ue does not need to monitor on multiple LBT bandwidths, thereby effectively improving transmission efficiency and transmission reliability of the sidestream communication.

Preferably, the selected sidelink communication scheduling grant corresponds to transmission of one or more media access control layer MAC protocol data units PDU.

Preferably, the resource allocation manner in the transmission resource selection or reselection process is based on at least one of a perceived resource allocation manner, a partially perceived resource allocation manner, and a random resource selection manner.

Preferably, for channel access of the shared spectrum, the step of performing a transmission resource selection or reselection procedure comprises the steps of: the sidelink communication time-frequency resource is selected for a transmission opportunity.

Preferably, the step of selecting the sidelink communication time-frequency resource for one transmission opportunity includes: and selecting a time-frequency resource from the candidate resource set reported by the physical layer as a side communication time-frequency resource, wherein a resource block RB corresponding to the time-frequency resource is positioned in a single resource block set.

Preferably, the step of selecting the sidelink communication time-frequency resource for one transmission opportunity further comprises: if the candidate resource set reported by the physical layer does not contain the candidate resource of which the corresponding resource block RB is positioned in the single resource block set, selecting a time-frequency resource from the candidate resource set reported by the physical layer as a side communication time-frequency resource.

Preferably, for channel access of the shared spectrum, the step of performing a transmission resource selection or reselection procedure comprises the steps of: and selecting side communication time-frequency resources for one or more transmission opportunities of the hybrid automatic repeat request (HARQ) retransmission.

Preferably, the step of selecting the sidelink communication time-frequency resource for the transmission opportunity of one or more HARQ retransmissions comprises: if enough corresponding Resource Blocks (RBs) exist in the residual available resources in the candidate resource set reported by the physical layer and are positioned in the candidate resources in the single resource block set, selecting side communication time-frequency resources for transmission opportunities of one or more HARQ retransmissions from the corresponding Resource Blocks (RBs) in the residual available resources in the candidate resources in the single resource block set.

Preferably, the step of selecting the sidelink communication time-frequency resource for the transmission opportunity of the one or more HARQ retransmissions further comprises: and if the corresponding resource block RB in the residual available resources in the candidate resource set reported by the physical layer is positioned under the condition that the candidate resources in the single resource block set are selected to the maximum extent, selecting side communication time-frequency resources aiming at the residual transmission opportunities of other HARQ retransmissions from the residual available resources in the candidate resource set reported by the physical layer.

Furthermore, according to the present invention, there is provided a user equipment comprising: a processor; and a memory storing instructions, wherein the instructions, when executed by the processor, perform the method described above.

Effects of the invention

The scheme of the invention comprises a method for selecting (or reselecting) resources by the side-by-side communication user equipment in the SL-U. In SL-U, the scheme of the present invention ensures that the sidestream communication ue can preferentially select the candidate resources mapped by the resource block RB on the same LBT bandwidth (or LBT sub-band), that is, when the ue performs LBT operation on the LBT bandwidth and listens that the channel is idle (idle), the sidestream communication transmission can be performed. In the scheme, the sidestream communication user equipment does not need to monitor on a plurality of LBT bandwidths, so that the transmission efficiency and the transmission reliability of sidestream communication are effectively improved.

Drawings

The foregoing and other features of the invention will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings in which:

fig. 1 is a schematic diagram illustrating LTE V2X UE side-by-side communication.

Fig. 2 is a schematic diagram illustrating a resource allocation scheme of LTE V2X.

Fig. 3 is a schematic diagram showing a basic procedure of a method performed by a user equipment in the first embodiment of the present invention.

Fig. 4 is a block diagram illustrating a user equipment according to an embodiment of the present invention.

Detailed Description

The invention is described in detail below with reference to the drawings and the detailed description. It should be noted that the present invention should not be limited to the specific embodiments described below. In addition, for the sake of brevity, detailed descriptions of well-known techniques, which are not directly related to the present invention, are omitted to prevent confusion of the understanding of the present invention.

Various embodiments in accordance with the present invention are described in detail below with respect to an example application environment for a 5G mobile communication system and its subsequent evolutions. However, it should be noted that the present invention is not limited to the following embodiments, but is applicable to many other wireless communication systems, such as a communication system after 5G, a 4G mobile communication system before 5G, and the like.

Some terms related to the present invention are described below, and unless otherwise specified, the terms related to the present invention are defined herein. The terms given in the present invention may be named differently in LTE, LTE-Advanced Pro, NR and subsequent communication systems, but the present invention uses unified terms, which when applied to a specific system may be replaced by terms used in the corresponding system.

3GPP:3rd Generation Partnership Project, third Generation partnership project

LTE: long Term Evolution Long term evolution technology

NR: new Radio, new air interface

PDCCH: physical Downlink Control Channel physical downlink control channel

DCI: downlink Control Information downlink control information

PDSCH: physical Downlink Shared Channel physical downlink shared channel

UE: user Equipment

eNB: evolutiond NodeB, evolved node B

gNB: NR base station

TTI: transmission Time Interval transmission time interval

OFDM: orthogonal Frequency Division Multiplexing orthogonal frequency division multiplexing

CP-OFDM: cyclic Prefix Orthogonal Frequency Division Multiplexing OFDM with cyclic prefix

C-RNTI: cell Radio Network Temporary Identifier cell radio network temporary identity

CSI: channel State Information channel State information

HARQ: hybrid Automatic Repeat Request hybrid automatic repeat request

CSI-RS: channel State Information Reference Signal channel State information reference Signal

CRS: cell Reference Signal cell-specific reference signals

PUCCH: physical Uplink Control Channel physical uplink control channel

PUSCH: physical Uplink Shared Channel physical uplink shared channel

UL-SCH: uplink Shared Channel uplink shared channel

CG: configured Grant, configured scheduling Grant

Sidelink: sidestream communication

SCI: sidelink Control Information, sidestream traffic control information

PSCCH: physical Sidelink Control Channel physical sidelink communication control channel

MCS: modulation and Coding Scheme modulation coding scheme

RB: resource Block, resource Block

RE: resource Element, resource unit

CRB: common Resource Block common resource block

CP: cyclic Prefix

PRB: physical Resource Block physical resource blocks

PSSCH: physical Sidelink Shared Channel physical sidelink communication shared channel

FDM: frequency Division Multiplexing frequency division multiplexing

RRC: radio Resource Control radio resource control

RSRP: reference Signal Receiving Power reference signal received power

SRS: sounding Reference Signal sounding reference signal

DMRS: demodulation Reference Signal demodulation reference signal

CRC: cyclic Redundancy Check cyclic redundancy check

PSDCH: physical Sidelink Discovery Channel physical sidelink discovery channel

PSBCH: physical Sidelink Broadcast Channel physical sidelink communication broadcast channel

SFI: slot Format Indication time slot format indication

TDD: time Division Duplexing time division duplexing

FDD: frequency Division Duplexing frequency division duplexing

SIB: system Information Block System information block

SIB1: system Information Block Type 1, system information Block type 1

SLSS: sidelink synchronization Signal sidestream communication synchronization signal

PSSS: primary Sidelink Synchronization Signal master synchronizing signal for side communication

SSSS: secondary Sidelink Synchronizaticn Signal side-row communication auxiliary synchronization signal

PCI: physical Cell ID, physical Cell identity

PSS: primary Synchronization Signal master synchronization signal

SSS: secondary Synchronization Signal auxiliary synchronization signal

BWP: bandwidth Part, bandWidth segment/section

And (3) GNSS: global Navigation Satellite System Global navigation satellite positioning System

SFN: system Frame Number System (radio) frame number

DFN: direct Frame Number direct frame number

IE: information Element, information element

SSB: synchronization Signal Block synchronization system information block

EN-DC: EUTRA-NR Dual Connection, LTE-NR dual connectivity

MCG: master Cell Group master cell group

SCG: secondary Cell Group group of secondary cells

PCell: primary Cell, primary Cell

SCell: secondary Cell, secondary Cell

PSFCH: physical Sidelink Feedback Channel physical sidelink communication feedback channel

SPS: semi-Persistant Scheduling, semi-static scheduling

TA: timing Advance, upstream Timing Advance

PT-RS: phase-Tracking Reference Signals, phase tracking reference signal

TB: transport Block, transport Block

CB: code Block, coding Block/Code Block

QPSK: quadrature Phase Shift Keying Quadrature phase Shift keying

16/64/256QAM: 16/64/256/Quadrature Amplitude Modulation quadrature amplitude modulation

AGC: auto Gain Control automatic gain control

TDRA (field): time Domain Resource Assignment time domain resource allocation indication (Domain)

FDRA (field): frequency Domain Resource Assignment indication of frequency domain resource allocation (Domain)

ARFCN: absolute Radio Frequency Channel Number absolute radio frequency channel numbering

SC-FDMA: single Carrier-Frequency Division Multiple Access, single Carrier-frequency division multiplexing multiple access

MAC: medium Access Control media access control layer

PDU: protocol Data Unit protocol data unit

DRX: discontinuous Reception discontinuous reception

SL-U: sidelink unlicensed sidestream communications over unlicensed spectrum

NR-U: NR unlicensed, NR communication over unlicensed spectrum

LBT: listen Before Talk listen before talk

The following is a description of the prior art in connection with the inventive arrangements. Unless otherwise indicated, the terms used in the description of the embodiments are the same as those used in the prior art.

It is noted that V2X referred to in the present specification has the same meaning as sidelink (sidelink). V2X herein may also represent sidestream communications; similarly, the side-row communication herein may also represent V2X, and is not specifically differentiated and defined hereinafter.

The resource allocation method of V2X (sidelink) communication and the transmission mode of V2X (sidelink) communication in the specification of the present invention can be replaced equivalently. The resource allocation pattern referred to in the specification may represent a transmission mode, and the referred transmission mode may represent a resource allocation pattern. In NR side row communication, transmission mode 1 indicates a transmission mode (resource allocation scheme) based on base station scheduling; transmission mode 2 represents a transmission mode (resource allocation scheme) based on user equipment awareness (sensing) and resource selection.

The PSCCH in the description of the invention is used to carry SCI. The PSCCHs referred to in the description of the present invention correspond to, or relate to, or schedule the same meaning as, the associated (associated) psch or corresponding (associated) psch. Similarly, reference in the specification to a PSSCH means that the corresponding, or related SCI (including both the first level SCI and the second level SCI) means the same meaning, and both refer to the associated (associated) SCI or the corresponding (associated) SCI. It is worth noting that the first stage SCI is called 1st stage SCI or SCI format 1-A, transmitted in PSCCH; the second level SCI is called 2nd stage SCI or SCI format 2-A (or SCI format 2-B), transmitted in the resources of the corresponding PSSCH.

In the description of the invention, NR sidestream communication (abbreviated as SL-U) is performed on an unlicensed spectrum (unlicensed spectrum), which may also be referred to as channel access (shared spectrum channel access) of a shared spectrum, i.e. on the unlicensed spectrum there may be user equipment accessing a channel through Wifi technology (wireless local area network technology based on IEEE 802.11 standard), and also NR sidestream communication user equipment accessing through a PC5 interface.

Parameter set (numeroloay) in NR (including NR sidelink) and in NR (including NR side link) Time slot (slot)

The parameter set (numerology) contains both meanings of subcarrier spacing and cyclic prefix CP length. Wherein NR supports 5 subcarrier spacings of 15k,30k,60k,120k,240khz (corresponding to μ=0, 1,2,3, 4), table 4.2-1 shows the supported transmission parameter sets, as specifically shown below.

Table 4.2-1 NR Supported subcarrier spacing

μ	Δf＝2 ^μ ·15[kHz]	CP (cyclic prefix)
			0	15	Normal state
1	30	Normal state
			2	60	Normal, extended
3	120	Normal state
			4	240	Normal state

Extended (Extended) CP is supported only when μ=2, i.e., in the case of 60kHz subcarrier spacing, and other subcarrier spacing cases support only normal CP. For Normal CP, each slot (slot) contains 14 OFDM symbols; for extended CP, each slot contains 12 OFDM symbols. For μ=0, i.e. 15kHz subcarrier spacing, 1 slot=1 ms; μ=1, i.e. 30kHz subcarrier spacing, 1 slot=0.5 ms; μ=2, i.e. 60kHz subcarrier spacing, 1 slot=0.25 ms, and so on.

NR andLTE has the same definition for subframes (subframes), representing 1ms. For a subcarrier spacing configuration μ, the slot number within 1 subframe (1 ms) may be expressed as In the range of 0 to->The slot number within 1 system frame (frame, duration 10 ms) can be expressed as +.>In the range of 0 to->Wherein (1)>Andthe definition of the case of different subcarrier spacings μ is shown in the table below.

Table 4.3.2-1: number of symbols included in each time slot in normal CP, number of time slots included in each system frame, number of time slots included in each subframe

Table 4.3.2-2: number of symbols contained in each time slot, number of time slots contained in each system frame, number of time slots contained in each subframe when expanding CP (60 kHz)

On the NR carrier, the numbered SFN range of system frames (or simply frames) is 0 to 1023. The concept of direct system frame number DFN is introduced in sidestream communication, with numbers ranging from 0 to 1023 as well, and the above description of the relationship between system frames and parameter sets (numerology) is equally applicable to direct system frames, e.g., one direct system frame is equally equal to 10ms in duration, one direct system frame includes 10 slots (slots) for 15kHz subcarrier spacing, etc. DFN is applied to timing on side-row communication carriers.

Parameter sets in LTE (including LTE V2X) and slots and subframes in LTE (including LTE V2X)

LTE only supports a subcarrier spacing of 15 kHz. Extended (Extended) CPs are supported in LTE, as are normal CPs. The subframe (subframe) duration is 1ms, comprising two slots, each slot duration being 0.5ms.

For Normal CP, each subframe contains 14 OFDM symbols, and each slot in a subframe contains 7 OFDM symbols; for extended CP, each subframe contains 12 OFDM symbols, and each slot in a subframe contains 6 OFDM symbols.

Resource block RB and resource element RE

Resource blocks RBs are defined in the frequency domain asThe RB is 180kHz in the frequency domain for a contiguous subcarrier, e.g., for a subcarrier spacing of 15 kHz. 15kHz x 2 for subcarrier spacing ^μ The resource element RE represents 1 subcarrier in the frequency domain and 1 OFDM symbol in the time domain.

Scene of sidestream communication

1) network-Coverage-free (Out-of-Coverage) side line communication: neither UE that is conducting sidelink communication has network coverage (e.g., the UE does not detect any cells meeting the "cell selection criterion" on the frequency that is needed for sidelink communication, meaning that the UE has no network coverage).

2) There is network Coverage (In-Coverage) side line communication: both UEs that are conducting sidelink have network coverage (e.g., a UE detects at least one cell that meets the "cell selection criteria" on the frequency that is needed for sidelink, indicating that the UE has network coverage).

3) Partial-Coverage (Partial-Coverage) side line communication: one of the UEs performing the sidestream communication has no network coverage and the other UE has network coverage.

From the UE side, the UE has only two scenarios of no network coverage and network coverage. Partial network coverage is described from the perspective of sidestream communications.

Basic procedure for LTE V2X (sidelink) communication

Fig. 1 is a schematic diagram illustrating LTE V2X UE side-by-side communication. First, UE1 transmits sidelink control information (SCI format 1) to UE2, carried by a physical layer channel PSCCH. SCI format 1 contains scheduling information of the PSSCH, for example, frequency domain resources of the PSSCH, etc. Next, UE1 transmits sidelink communication data to UE2, carried by the physical layer channel PSSCH. The PSCCH and corresponding pscsch are frequency division multiplexed, i.e., the PSCCH and corresponding pscsch are located on the same subframe in the time domain and on different RBs in the frequency domain. In LTE V2X, one transport block TB may contain only one initial transmission, or one initial transmission and one blind retransmission (blind retransmission, representing a retransmission not based on HARQ feedback).

The specific design modes of PSCCH and PSSCH are as follows:

1) The PSCCH occupies one subframe in the time domain and two consecutive RBs in the frequency domain. The scrambling sequence is initialized with a predefined value 510. The PSCCH may carry SCI format 1, where SCI format 1 includes at least frequency domain resource information of the PSCCH. For example, for the frequency domain resource indication field, SCI format 1 indicates the starting subchannel (sub-channel) number and the number of consecutive subchannels of the PSSCH corresponding to the PSCCH.

2) The PSSCH occupies one subframe in the time domain, and the corresponding PSCCH employs Frequency Division Multiplexing (FDM). The PSSCH occupies one or more consecutive sub-channels in the frequency domain, the sub-channels representing n in the frequency domain _subCHsize Successive RBs, n _subCHsize The number of starting subchannels and consecutive subchannels is indicated by the frequency domain resource indication field of SCI format 1, configured by the RRC parameters.

Resource allocation mode Transmission Mode 3/4 of LTE V2X

Fig. 2 shows two resource allocation schemes of LTE V2X, which are called base station scheduling-based resource allocation (Transmission Mode) and UE aware (serving) -based resource allocation (Transmission Mode), respectively. In the NR side communication, a transmission mode 3 of LTE V2X corresponds to a transmission mode 1 in NR V2X and is a transmission mode based on base station scheduling; the transmission mode 4 of LTE V2X corresponds to the transmission mode 2 in NR V2X, and is a transmission mode based on UE awareness. In LTE V2X, when there is eNB network coverage, the base station may configure the resource allocation manner of the UE, or the transmission mode of the UE, through UE-level dedicated RRC signaling (dedicated RRC signaling) SL-V2X-ConfigDedicated, specifically:

1) Resource allocation method (Transmission Mode 3) based on base station scheduling: the resource allocation method based on the base station scheduling indicates that the frequency domain resource used by the sidestream communication comes from the scheduling of the base station. Transmission mode 3 includes two scheduling modes, dynamic scheduling and semi-persistent scheduling (SPS), respectively. For dynamic scheduling, the frequency domain resources including PSSCH in the UL scheduling grant (DCI format 5A), and the CRC of the PDCCH or EPDCCH carrying DCI format 5A is scrambled by SL-V-RNTI. For SPS semi-persistent scheduling, the base station passes the IE: the SPS-ConfigSL-r14 configures one or more (up to 8) configured scheduling grants, each configured scheduling grant containing a scheduling grant number (index) and a resource period of the scheduling grant. The UL scheduling grant (DCI format 5A) includes the frequency domain resource of the PSSCH, and indication information of the scheduling grant number (3 bits) and indication information of SPS activation (activation) or release (deactivation). The CRC of the PDCCH or EPDCCH carrying DCI format 5A is scrambled by SL-SPS-V-RNTI.

Specifically, when RRC signaling SL-V2X-ConfigDedimded is set to scheduled-r14, this means that the UE is configured to be based on the transmission mode of the base station schedule. The base station configures the SL-V-RNTI or SL-SPS-V-RNTI through RRC signaling and transmits an uplink scheduling grant (UL grant) to the UE through PDCCH or EPDCCH (DCI format 5A, CRC scrambled with SL-V-RNTI or with SL-SPS-V-RNTI). The uplink scheduling grant at least includes scheduling information of PSSCH frequency domain resources in sidestream communication. When the UE successfully monitors PDCCH or EPDCCH scrambled by SL-V-RNTI or SL-SPS-V-RNTI, the PSSCH frequency domain resource indication field in the uplink scheduling grant (DCI format 5A) is used as indication information of the PSSCH frequency domain resource in the PSCCH (SCI format 1), and the PSCCH (SCI format 1) and the corresponding PSSCH are sent.

For semi-persistent scheduling SPS in transmission mode 3, the UE receives a SL-SPS-V-RNTI scrambled DCI format 5A on downlink subframe n. If the indication information of SPS activation is included in the DCI format 5A, the UE determines the frequency domain resource of the PSSCH according to the indication information in the DCI format 5A, and determines the time domain resource of the PSSCH (the sending subframe of the PSSCH) according to the information such as the subframe n.

2) UE aware (serving) based resource allocation scheme (Transmission Mode 4): the UE-aware-based resource allocation approach represents a process in which resources for sidestream communication are based on UE awareness (sensing) of a candidate set of available resources. The RRC signaling SL-V2X-configdediated when set to UE-Selected-r14 indicates that the UE is configured to be based on the UE-aware transmission mode. In the UE-aware-based transmission mode, the base station configures an available transmission resource pool, and the UE determines a side communication transmission resource of the PSSCH in the transmission resource pool (resource pool) according to a certain rule (for a detailed description of a procedure, see LTE V2X UE-aware procedure part) and transmits the PSCCH (SCI format 1) and the corresponding PSSCH.

Sidestream communication resource pool (sidelink resource pool)

In the sidestream communication, the resources transmitted and received by the UE belong to a resource pool (resource pool). For example, for a transmission mode based on base station scheduling in sidestream communication, the base station schedules transmission resources in a resource pool for sidestream communication UEs, or for a transmission mode based on UE awareness in sidestream communication, the UEs determine transmission resources in the resource pool.

For NR sidelink communication, sub-channel based resource allocation is supported in the frequency domain with minimum granularity, i.e. for PSSCH transmission, the resources occupied in the frequency domain are integer sub-channels. One subchannel may represent several resource blocks RBs consecutive in the frequency domain.

Resource allocation mode based on perception

For the perceived resource allocation (resource allocation 2), the sidelink communication ue selects candidate resources within a time window (optionally, resource selection windows [ n+t1, n+t2 ]), determines candidate resources overlapping with the reserved resources according to reserved resources indicated by PSCCH sent by other ues in the listening slot, and excludes the overlapped candidate resources (include). The physical layer reports the set of candidate resources that are not excluded to the MAC layer, which selects transmission resources for the PSSCH/PSCCH. The set of transmission resources selected by the MAC layer is referred to as a selected sidelink communication schedule grant (selected sidelink grant). The sidestream communication resources included in a selected sidestream communication scheduling grant may be used for the primary transmission and all retransmissions of one MAC PDU (corresponding to one transport block TB) or may be used for the primary transmission and all retransmissions of a plurality of MAC PDUs (corresponding to a plurality of transport blocks TBs). The present invention is not limited in this regard.

Resource selection window [ n+T1, n+T2 ]]

In a perceived (or partially perceived) based resource allocation approach, the higher layer requests or triggers the physical layer to determine the resources (perceived or partially perceived) for the PSSCH/PSCCH transmission on slot n. The resource selection window is defined as [ n+T1, n+T2 ]]I.e. the user equipment selects transmission resources within the window. Wherein T1 satisfies the conditionThe choice of T1 depends on the implementation of the user equipment; the RRC configuration information includes a configuration list sl-selection Window List of a resource selection window, wherein the list corresponds to a given priority prio _TX The element (priority of transmission PSSCH) is denoted as T _2min . If T is _2min Less than the remaining packet delay budget (remaining packet delay budget, abbreviated as remaining PDB), then T2 satisfies condition T _2min T2 +.remaining PDB, the choice of T2 depends on the implementation of the user equipment; otherwise T2 is set to remaining PDB. />Is defined as (mu) _SL Subcarrier spacing parameter indicating sidestream communication, i.e. subcarrier spacing is +.>)：

Table 8.1.4-2:is +.>

Table 8.1.4-1:is of the value of (2)

LBT (Listen Before Talk) mechanism

For wireless communications over unlicensed spectrum (unlicensed spectrum), some countries or regions (e.g., european regions) specify that user equipment needs to perform LBT operations, i.e., a "listen before talk" mechanism, also referred to as channel access (channel access) operation, prior to transmission of the wireless communications, indicating a mechanism to determine channel availability by perceiving (sensing) a channel. Specifically, during a period of time before communication transmission, the ue transmits only when it monitors that the channel is idle; otherwise, the user equipment does not transmit.

In particular, for NR communications (NR-U) over unlicensed spectrum (or for SL-U), the basic time unit of the perceived channel may beT is _sl =9 μs. In this time unit, if the energy detected by the base station or the user equipment on the channel is below the energy threshold value X _Thresh When the duration of (a) equals or exceeds 4 mus, then the base station or user equipment considers the channel to be idle for that unit of time (alternatively referred to as LBT success). It is worth noting that the channel (channel) that the base station or user equipment detects energy and uses to determine whether it is idle represents one carrier, or a part of the carrier, containing one set of consecutive resource blocks RB. The channel may also be referred to as an LBT bandwidth (LBT bandwidth), or an LBT sub-band, or an RB set (RB set). One LBT bandwidth or RB set may be equal to 20MHz in the frequency domain, i.e., one RB set may exist on a carrier of 20 MHz. For a 15kHz subcarrier spacing, on one carrier (a carrier exceeding 20MHz, for example 40MHz,60MHz,80 MHz), the number of resource blocks RBs corresponding to a plurality of RB sets contained and Guard bands (abbreviated GB) between two consecutive RB sets may be as shown in the following table:

Table 1: at 15kHz and 30kHz subcarrier spacing, all RB sets on one carrier and the number of RBs contained in GB

In the above table, 105-6-105 indicates that the carrier contains two consecutive RB sets, each containing 105 RBs, taking a subcarrier spacing of 15kHz and a carrier bandwidth of 40MHz as an example. Between these two RB sets there is one guard band GB containing 6 consecutive RBs, containing 216 consecutive RBs in total, and so on in table 1.

It is noted that LBT operations performed by (side-row communication) user equipments on different RB sets may be independent of each other (i.e. not related to each other). For example, the user equipment detects that the channel is idle on RB set 1 and may be occupied (or busy) on RB set 2. If a sidelink communication user equipment selects resources for transmitting PSSCH/PSCCH to contain both (all or part of) the RBs corresponding to RB set 1 and RB set 2, the user equipment can transmit the corresponding PSSCH/PSCCH if and only if the user equipment detects that the channel is idle on both RB set 1 and RB set 2.

Specific examples, embodiments, and the like according to the present invention will be described in detail below. As described above, examples, embodiments, and the like described in the present disclosure are illustrative for easy understanding of the present invention, and are not intended to limit the present invention.

Example one

Fig. 3 is a schematic diagram showing a basic procedure of a method performed by a user equipment according to the first embodiment of the present invention.

The method performed by the user equipment according to the first embodiment of the present invention will be described in detail with reference to the basic process diagram shown in fig. 3.

As shown in fig. 3, in a first embodiment of the present invention, the steps performed by the user equipment include:

in step S101, the sidestream communication user device selects to generate (select to create) a selected sidestream communication scheduling grant (selected sidelink grant), and optionally, sidestream communication data is available on the logical channel.

Wherein, optionally, the one selected sidestream communication scheduling grant corresponds to transmission of one or more MAC protocol data units, PDUs.

In step S102, the user equipment performs (performance) a transmission resource selection (reselection) procedure.

Wherein, optionally, if the result of the resource selection (or reselection) check is triggering a resource selection (or reselection), the user equipment performs a transmit resource selection (or reselection) procedure.

Optionally, the resource allocation manner of the user equipment is based on a perceived resource allocation manner, or based on a partially perceived resource allocation manner, or random resource selection.

Wherein, optionally, for channel access (shared spectrum channel access) of the shared spectrum, or for said sidestream communication on unlicensed spectrum,

the ue selects (randomly) a side communication time-frequency resource for one transmission opportunity (one transmission opportunity), where optionally, the ue selects (randomly) one time-frequency resource from a candidate resource set reported (or indicated) by a physical layer, where the time-frequency resource corresponds (or is associated with, or is mapped to) a resource block RB in a single (or one) resource block set (RB set); optionally, if the candidate resource set reported by the physical layer does not include candidate resources of the corresponding (or associated or mapped) resource block RB in a single (or one) resource block set (RB set), the user equipment (randomly) selects one time-frequency resource in the candidate resource set reported by the physical layer,

and/or the number of the groups of groups,

if the user equipment selects one or more HARQ retransmissions, the user equipment selects (randomly) side row communication time-frequency resources from available (available) side row communication resources for the one or more (HARQ retransmission) transmission opportunities, wherein optionally, for the one or more (HARQ retransmission) transmission opportunities, if (sufficient) corresponding (or associated or mapped) resource blocks RB exist in the remaining available resources in the candidate resource set reported by the physical layer, candidate resources in a single (or one) resource block set (RB set) are selected for the one or more (HARQ retransmission) transmission opportunities from the corresponding (or associated or mapped) resource blocks RB in the remaining available resources; optionally, for the one or more transmission opportunities (of HARQ retransmissions), if the number of selected time-frequency resources is smaller than the number of selected HARQ retransmissions in the case (maximally selected) that the user equipment has maximized selection of a corresponding (or associated or mapped) resource block RB among the remaining available resources in the candidate resource set reported by the physical layer in the candidate resources in a single (or one) resource block set (RB set), the user equipment selects a time-frequency resource for the remaining other (remaining) transmission opportunities (randomly) in the candidate resource set reported by the physical layer, that is, excluding the transmission opportunities (HARQ retransmissions) of the corresponding resource block RB that has been selected in the side communication resources of the single RB set) of the time-frequency resource that has not been selected.

Fig. 4 is a block diagram showing a user equipment UE according to the present invention. As shown in fig. 4, the user equipment UE40 comprises a processor 401 and a memory 402. The processor 401 may include, for example, a microprocessor, a microcontroller, an embedded processor, or the like. The memory 402 may include, for example, volatile memory (such as random access memory RAM), a Hard Disk Drive (HDD), non-volatile memory (such as flash memory), or other memory. The memory 402 has stored thereon program instructions. Which, when executed by the processor 401, may perform the above-described method performed by the user equipment as described in detail herein.

The method and the apparatus involved of the present invention have been described above in connection with preferred embodiments. It will be appreciated by those skilled in the art that the methods shown above are merely exemplary and that the embodiments described above can be combined with one another without contradiction. The method of the present invention is not limited to the steps and sequences shown above. The network nodes and user equipment shown above may comprise further modules, e.g. modules that may be developed or developed in the future that may be used for a base station, MME, or UE, etc. The various identifiers shown above are merely exemplary and are not intended to be limiting, and the present invention is not limited to the specific cells that are examples of such identifiers. Many variations and modifications may be made by one of ordinary skill in the art in light of the teachings of the illustrated embodiments.

It should be understood that the above-described embodiments of the present invention may be implemented by software, hardware, or a combination of both software and hardware. For example, the various components within the base station and user equipment in the above embodiments may be implemented by a variety of means including, but not limited to: analog circuit devices, digital Signal Processing (DSP) circuits, programmable processors, application Specific Integrated Circuits (ASICs), field Programmable Gate Arrays (FPGAs), programmable logic devices (CPLDs), and the like.

In this application, the "base station" may refer to a mobile communication data and control switching center with a larger transmission power and a wider coverage area, including functions of resource allocation scheduling, data receiving and transmitting, and the like. "user equipment" may refer to user mobile terminals including, for example, mobile phones, notebooks, etc., that may communicate wirelessly with a base station or micro base station.

Furthermore, embodiments of the invention disclosed herein may be implemented on a computer program product. More specifically, the computer program product is one of the following: has a computer readable medium encoded thereon with computer program logic that, when executed on a computing device, provides relevant operations to implement the above-described aspects of the invention. The computer program logic, when executed on at least one processor of a computing system, causes the processor to perform the operations (methods) described in embodiments of the invention. Such an arrangement of the present invention is typically provided as software, code and/or other data structures arranged or encoded on a computer readable medium, such as an optical medium (e.g., CD-ROM), floppy disk or hard disk, or other a medium such as firmware or microcode on one or more ROM or RAM or PROM chips, or as downloadable software images in one or more modules, shared databases, etc. The software or firmware or such configuration may be installed on a computing device to cause one or more processors in the computing device to perform the techniques described by embodiments of the present invention.

Furthermore, each functional module or each feature of the base station apparatus and the terminal apparatus used in each of the above embodiments may be implemented or performed by a circuit, which is typically one or more integrated circuits. Circuits designed to perform the functions described in this specification may include a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC) or a general purpose integrated circuit, a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, or discrete hardware components, or any combination thereof. A general purpose processor may be a microprocessor, or the processor may be an existing processor, controller, microcontroller, or state machine. The or each circuit may be configured by digital circuitry or may be configured by logic circuitry. In addition, when advanced technologies capable of replacing the current integrated circuits are presented due to advances in semiconductor technology, the present invention can also use integrated circuits obtained using the advanced technologies.

While the invention has been shown above in connection with the preferred embodiments thereof, it will be understood by those skilled in the art that various modifications, substitutions and changes may be made thereto without departing from the spirit and scope of the invention. Accordingly, the invention should not be limited by the above-described embodiments, but by the following claims and their equivalents.

Claims

1. A method performed by a user equipment, comprising the steps of:

selecting and generating a selected sidestream communication scheduling license; and

a transmission resource selection or reselection procedure is performed.

2. The method of claim 1, wherein,

the selected sidelink communication scheduling grant corresponds to transmission of one or more media access control layer MAC protocol data units, PDUs.

3. The method of claim 1, wherein,

the resource allocation method in the transmission resource selection or reselection process is based on at least one of a perceived resource allocation method, a partially perceived resource allocation method, and a random resource selection method.

4. The method of claim 1, wherein,

for channel access of the shared spectrum, the step of performing a transmission resource selection or reselection procedure comprises the steps of:

the sidelink communication time-frequency resource is selected for a transmission opportunity.

5. The method of claim 4, wherein,

the step of selecting the sidestream communication time-frequency resource for one transmission opportunity comprises the following steps:

and selecting a time-frequency resource from the candidate resource set reported by the physical layer as a side communication time-frequency resource, wherein a resource block RB corresponding to the time-frequency resource is positioned in a single resource block set.

6. The method of claim 5, wherein,

the step of selecting the sidestream communication time-frequency resource for one transmission opportunity further comprises:

if the candidate resource set reported by the physical layer does not contain the candidate resource of which the corresponding resource block RB is positioned in the single resource block set, selecting a time-frequency resource from the candidate resource set reported by the physical layer as a side communication time-frequency resource.

7. The method of claim 1, wherein,

and selecting side communication time-frequency resources for one or more transmission opportunities of the hybrid automatic repeat request (HARQ) retransmission.

8. The method of claim 7, wherein,

the step of selecting sidestream communication time-frequency resources for transmission opportunities of one or more HARQ retransmissions comprises:

if enough corresponding Resource Blocks (RBs) exist in the residual available resources in the candidate resource set reported by the physical layer and are positioned in the candidate resources in the single resource block set, selecting side communication time-frequency resources for transmission opportunities of one or more HARQ retransmissions from the corresponding Resource Blocks (RBs) in the residual available resources in the candidate resources in the single resource block set.

9. The method of claim 8, wherein,

the step of selecting sidestream communication time-frequency resources for the transmission opportunity of one or more HARQ retransmissions further comprises:

and if the corresponding resource block RB in the residual available resources in the candidate resource set reported by the physical layer is positioned under the condition that the candidate resources in the single resource block set are selected to the maximum extent, selecting side communication time-frequency resources aiming at the residual transmission opportunities of other HARQ retransmissions from the residual available resources in the candidate resource set reported by the physical layer.

10. A user equipment, comprising:

a processor; and

a memory in which instructions are stored,

wherein the instructions, when executed by the processor, perform the method according to any of claims 1-9.