CN108632781B - Resource selection or reselection method in vehicle-to-outside communication and user equipment - Google Patents

Abstract

The present invention provides a resource selection or reselection method performed by a user equipment (UE) in vehicle-to-external (V2X) communication and the UE. The method includes the steps of: detecting physical bypass control channels (PSCCH) sent by other UEs; selecting single subframe resources from single subframe resources that do not overlap with single subframe resources reserved by the detected PSCCH; and selecting single subframe resources in the selected single subframe resources. Send on the physical bypass shared channel (PSSCH).

Description

Resource selection or reselection method and user equipment in vehicle-to-external communication

Technical field

The present invention generally relates to communication technology, and more specifically, to a resource selection or reselection method in vehicle-to-everything (V2X) communication and a user equipment (UE) that executes the method.

Background technique

In the 3rd Generation Partnership Project (3GPP) standard, the direct communication link between devices is called sidelink. Similar to the uplink and downlink, there are also control channels and data channels on the sidelink. , the former is called the physical sidelink control channel (English full name: Physical Sidelink Control CHannel, English abbreviation: PSCCH), and the latter is called the physical bypass shared channel (English full name: Physical Sidelink Shared CHannel, English abbreviation: PSSCH). PSCCH is used to indicate the time-frequency domain resource location, modulation and coding mode, and priority of data carried in PSSCH for PSSCH transmission. PSSCH is used to carry data.

Control information and data in vehicle-to-external communication (English full name: Vehicle to Vehicle/Perdestrian/Infrastructure/Network, English abbreviation: V2X) can be transmitted through the bypass. At this time, V2X communication includes two transmission modes, namely transmission mode 3 ( Mode 3) and transmission mode 4 (Mode 4). For Mode 3, the PSCCH and PSSCH transmission resources of a UE (referred to as V2X UE, the same below) are allocated by the evolved node B (eNB). The UE receives the eNB through the physical downlink control channel (PDCCH) or evolved PDCCH (EPDCCH). ) determines the transmission resources of PSCCH and PSSCH. In Mode 4, the transmission resources of PSCCH and PSSCH are independently selected by the UE based on the channel detection results. During the channel detection process, the UE first determines the time-frequency resource location and priority of the scheduled PSSCH by receiving the PSCCH sent by other UEs, and then further detects the demodulation reference signal received power (PSSCH-RSRP) of the scheduled PSSCH, and Resources with PSSCH-RSRP higher than a specific threshold are excluded; the UE then calculates the average received energy (S-RSSI) of the remaining resources, and finally randomly selects a resource from the resources with the lowest S-RSSI as the transmission resource.

In the Rel-14 3GPP standard, UEs using Mode 3 or Mode 4 are configured according to resource pools. In order to ensure that the time-frequency resources allocated to UEs using Mode 3 are not interfered with by other UEs, the Mode 3 resource pool and Mode 4 Resource pools should be orthogonal to each other. However, because the resource pool is configured semi-statically and the number of UEs using a certain resource pool changes dynamically, if the resources in the resource pool are not coordinated with the number of UEs using the resource pool, it may lead to a waste of resources in the resource pool or Therefore, configuring multiple resource pools is not conducive to improving the utilization efficiency of time-frequency resources, and may also have a negative impact on the performance of the V2X system.

From the above analysis, we can see that from the perspective of resource utilization efficiency and V2X system performance, Mode 3 and Mode 4 UEs should be able to work in the same resource pool. However, in this case, how to effectively avoid or reduce the use of Mode 3 UEs? There is currently no effective technical solution for mutual interference with UEs using Mode 4.

Contents of the invention

According to an aspect of the present invention, a resource selection or reselection method performed by a user equipment (UE) in vehicle-to-everything (V2X) communication is provided, which includes the steps of: detecting physical bypass control channels (PSCCH) sent by other UEs ); select a single subframe resource from a single subframe resource that does not overlap with the detected single subframe resource reserved by the PSCCH; and transmit a physical bypass shared channel (PSSCH) on the selected single subframe resource.

According to another aspect of the present invention, a user equipment UE that performs a resource selection or reselection method in vehicle-to-external V2X communication is provided, which includes: a detection module for detecting the physical bypass control channel PSCCH sent by other UEs; a resource selection or reselection module configured to select a single subframe resource among single subframe resources that do not overlap with the detected single subframe resource reserved by the PSCCH; and a sending module that sends the physical bypass sharing on the selected single subframe resource. Channel PSSCH.

Through the above method and device, interference on PSCCH scheduling and reserved single subframe resources can be better avoided, the utilization efficiency of time-frequency resources can be improved, and the performance of the V2X system can be improved.

Description of the drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

Figure 1 is a flow chart of a resource selection or reselection method according to an embodiment of the present invention;

Figure 2 is a block diagram of a user equipment (UE) that performs a resource selection or reselection method in V2X communication according to an embodiment of the present invention.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present invention and cannot be construed as limiting the present invention.

Those skilled in the art will understand that, unless expressly stated otherwise, the singular forms "a", "an", "the" and "the" used herein may also include the plural form. It should be further understood that the word "comprising" used in the description of the present invention refers to the presence of stated features, integers, steps, operations, elements and/or components, but does not exclude the presence or addition of one or more other features, Integers, steps, operations, elements, components and/or groups thereof. It will be understood that when we refer to an element being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may also be present. Additionally, "connected" or "coupled" as used herein may include wireless connections or wireless couplings. As used herein, the term "and/or" includes all or any unit and all combinations of one or more of the associated listed items.

It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It should also be understood that terms, such as those defined in general dictionaries, are to be understood to have meanings consistent with their meaning in the context of the prior art, and are not to be used in an idealistic or overly descriptive manner unless specifically defined as here. to explain the formal meaning.

Those skilled in the art can understand that the "user equipment" and "terminal equipment" used here include not only wireless signal receiver equipment, but also include wireless signal receiver equipment without transmission capabilities, as well as receiving and transmitting hardware. A device that has receiving and transmitting hardware capable of conducting two-way communications on a two-way communication link. Such equipment may include: cellular or other communication equipment with a single line display or a multi-line display or a cellular or other communication equipment without a multi-line display; PCS (Personal Communications Service, personal communication system), which can combine voice, data Processing, fax and/or data communication capabilities; PDA (Personal Digital Assistant), which may include a radio frequency receiver, pager, Internet/Intranet access, web browser, notepad, calendar and/or GPS (Global Positioning System (Global Positioning System) receiver; a conventional laptop and/or palmtop computer or other device having and/or including a radio frequency receiver. As used herein, "user equipment", "terminal equipment" may be portable, transportable, installed in a vehicle (air, maritime and/or land), or adapted and/or configured to operate locally, and/ or in distributed form, operating at any other location on Earth and/or space. The "user equipment" and "terminal equipment" used here can also be communication terminals, Internet access terminals, music/video playing terminals, for example, they can be PDA, MID (Mobile Internet Device, mobile Internet device) and/or have music/video A mobile phone with playback function can also be a smart TV, set-top box and other devices.

In order to increase resource utilization and improve V2X system performance, UEs using Mode 3 and UEs using Mode 4 must work in the same resource pool. In this case, in order to avoid or reduce mutual interference between the two UEs, this application proposes a resource selection and reselection method in V2X communication.

Figure 1 is a flow chart of a resource selection or reselection method according to an embodiment of the present invention.

Referring to Figure 1, in step 101, the UE detects a physical bypass control channel (PSCCH) (SCI X) in the format of sidelink control information (Sidelink Control Information, SCI) For example, the UE is a UE adopting Mode 4. The UE detects the PSCCH sent by other UEs to obtain at least one of the following information: the transmission mode used by the PSCCH to send the UE, the priority of the PSSCH scheduled by the PSCCH, the PSSCH frequency domain resource location scheduled by the PSCCH, and the resource reservation indicated by the PSCCH. Stay period, etc.

The UE may detect SCI X on all PSCCH resources in the transmission resource pool currently selected by the UE, or only detect SCI The location of the resource. For example, the UE only detects SCI Detect SCI X on.

In step 102, the UE selects a single subframe resource among single subframe resources that do not overlap with the detected single subframe resource reserved by the PSCCH.

Define a single-subframe resource (single-subframe resource) R _{x, y} as TTI L _subCH consecutive sub-channels starting from sub-channel x, where y represents TTI/> The relative index in the resource pool, L _subCH , is determined by the UE upper layer and represents the number of sub-channels used for PSSCH transmission. If the UE performs resource selection or reselection in subframe n, the UE shall consider the continuous L _subCH subchannels on any subframe belonging to the resource pool within the range [n+T ₁ , n+T ₂ ] as candidate single subframes resources, where T ₁ and T ₂ are determined by the UE implementation, and T ₁ ≤ 4, 20 ≤ _{T 2} ≤ 100, the total number of single subframe resources is recorded as M _total , and the set of M _total candidate single subframe resources is S. It should be noted that if the UEs in the resource pool use multiple TTI lengths, for example, some UEs use a TTI with a length of 1ms, and some UEs use a TTI with a length of 0.5ms, then the UE can be considered as single when selecting or reselecting resources. The TTI length of the frame resource is the same as the TTI length adopted by the UE.

For any single subframe resource R _x,y in the set S, if there is a variable j∈{0,1,...,C _resel -1} such that the single subframe resource _Overlaps with the reserved _resources indicated in SCI Single subframe resources R _{x, y} are excluded when selecting or reselecting resources.

According to an embodiment of the present invention, if the detected SCI

According to another embodiment _of the present invention, if the detected SCI Single subframe resources are selected from single subframe resources whose frame resources do not overlap.

For example, the specific PSCCH format is SCI 1 defined in 3GPP Release 14, or a format different from SCI 1 defined in 3GPP Release 14, or has the same number of bits as SCI1 defined in 3GPP Release 14, and each domain The meaning is the same, but one or more specific bits in the reserved bit field are 1.

According to yet another embodiment of the present invention, the UE further measures the bypass reference signal received power (PSSCH-RSRP) of the PSSCH scheduled by SCI Select a single subframe resource from single subframe resources that do not overlap. _Specifically , the value _of the priority field contained _in SCI value greater than Where prio _TX represents the value of the priority field in the PSCCH to be sent next indicated by the UE higher layer, Δ is the value configured or pre-configured by the eNB,/> Indicates the i-th SL-ThresPSSCH-RSRP in SL-ThresPSSCH-RSRP-List-r14 defined in 3GPP standard 36.331V14.1.0, where i=(prio _TX +Δ)*8+prio _RX +1, then the UE is in Single subframe resources R _{x, y} are excluded from S when selecting or reselecting resources.

The UE further excludes resources from set S in the manner defined in 3GPP Release 14.

In step 103, the UE sends a physical bypass shared channel (PSSCH) on the selected single subframe resource.

The above technical solution of the present application will be further described below in combination with specific application situations and in the mode of interaction between devices.

Situation one

In case 1, SCI The same, and the meaning of each field is the same, but one or more specific bits in the reserved bit field can be 1 (all bits in the reserved bit field in the existing SCI 1 are 0). When performing resource selection or reselection, the UE selects a single subframe resource among single subframe resources that do not overlap with the detected single subframe resource reserved by the PSCCH. Specific steps are as follows:

In step 201, the UE detects SCI X sent by other UEs.

For example, in this case, the UE that sends SCI X is the UE that adopts Mode 3.

According to an implementation method of this situation, the UE using Mode 3 determines the value of each field in SCI The value of the "Number of subframes in the resource pool corresponding to the reserved interval" field, and the value of the "Number of sub-channels included in the frequency resource and the location of the sub-channel" field in SCI X. Preferably, the physical layer signaling is UE-specific signaling, scrambled by a specific cell radio network temporary identifier C-RNTI, and which UE is selected as the sending UE of SCI X is decided by the eNB. According to another implementation of this situation, the UE using Mode 3 determines the value of each field in SCI The value of the "number of subframes in the resource pool corresponding to the resource reservation interval" field in "Number" field value. The physical layer control signaling in the above two implementations should be different from the downlink control indication format 5A (DCI 5A) defined by the current standard. The UE that receives the physical layer control signaling only sends SCI PSSCH is sent on the frequency resource.

According to the implementation method 1 of this situation, SCI X is different from the existing SCI 1. The content of SCI Number D1, CRC, subframe interval G1 of the first reserved resource, and the number and location of subchannels included in a single subframe resource. The subframe position of the first reserved resource indicates the interval between the subframe where the SCI X is located and the subframe where the first reserved resource is located. If the subframe where SCI Resources are reserved, where i=0,1,2,…,M-1, the value of M is defined by the standard or configured by the eNB, and M can be positive infinity; j=0 and/or 1, the specific value is defined by the standard or eNB configuration. It should be noted that if D1 in SCIX is indicated as a specific value, such as 0, or if SCI D1 in j×G1+i×D1 is replaced with Pstep or Pmin, where Pstep is the basic resource reservation step size of the current resource pool, and Pmin is the minimum resource reservation interval supported by the current resource pool. The UE receives eNB signaling , standard definition, or preconfiguration determines the specific values of these two parameters.

According to the second implementation method of this actual situation, SCI The first bit of the field is 1, which is used to distinguish SCI X and SCI 1. If the subframe where SCI Reserved, where i=0,1,2,…,M-1, the value of M is defined by the standard or configured by eNB, and M can be positive infinity; j=0 and/or 1, the specific value is defined by the standard or eNB Configuration; G2 is the value of the Time gap between initial transmission and retransmission field in SCI 1, and D2 is the number of subframes corresponding to the value of the Resource reservation field in SCI 1.

In step 202, for any single subframe resource R _x,y in the set S, if there is a variable j∈{0,1,...,C _resel -1} such that the single subframe resource _Overlaps with the reserved _resources indicated in SCI Single subframe resources R _{x, y} are excluded from S during resource selection or reselection. Alternatively, if the value prio _RX included in the priority field (Priority) _in SCI

The UE may further exclude resources from set S in the manner defined in 3GPP Release 14.

The UE randomly selects a single subframe resource from the remaining resources for data transmission.

In step 203, the UE sends PSCCH on the PSCCH resource corresponding to the selected single subframe resource, and sends PSSCH on the selected single subframe resource.

Situation 2

In case 2, SCI Rel-14 UE. Type 3 is different from SCI 1. For example, the value of one or more specific bits in the reserved bit field is 1. Preferably, the sending UE of type 3 is a new version UE operating in mode 4. According to the implementation method 1 of this situation, if the data sent by the new version UE working in mode 3 needs to be received by the UE, the new version UE of mode 3 sends the type 2 SCI; according to the implementation method 2 of this situation, if the data sent by the new version UE working in mode 3 is The data sent by the new version UE of mode 3 needs to be received by the UE, so the new version UE of mode 3 sends type three SCI. At the same time, SCI X Type 1, Type 2, and Type 3 are different from each other. If the SCI X received by the UE is type 2, after the UE receives the SCI X, the UE can further measure the PSSCH-RSRP of the PSSCH scheduled by the SCI If any single subframe resource in the UE may overlap with the single subframe resource reserved by the UE sending SCI If the frame resources overlap and the measured PSSCH-RSRP is greater than a certain threshold, the UE should exclude the single subframe resource; preferably, the value of the specific threshold should be higher than Where prio _RX is the value containing the priority field (Priority ₎ in SCI Indicates the i-th SL-ThresPSSCH-RSRP in SL-ThresPSSCH-RSRP-List-r14 defined in 3GPP standard 36.331V14.1.0, i=prio _TX *8+prio _RX +1. If the SCI X received by the UE is type 3, the UE will further measure the PSSCH-RSRP of the scheduled PSSCH after receiving the SCI If the frame resource may overlap with the single subframe resource reserved in SCI X, and the measured PSSCH-RSRP is greater than a certain threshold, the UE should exclude the single subframe resource. Preferably, the following operations are performed only when the UE is working in a specific resource pool configured by the eNB. For example, the specific resource pool is a transmission resource pool configured for 3GPP version 14Mode 3 UE. Proceed as follows:

In step 301, the UE detects SCI X sent by other UEs.

In this case, if the SCI X received by the UE in subframe m is exactly the same as the existing SCI 1, the UE can adopt the following two methods to determine the reserved resources:

Method 1: The UE considers that the resources indicated by the "frequency resource location and number of included sub-channels" field on subframe m+j×G3+i×D3 _l are reserved, where i=0,1,2,… ,M-1, the value of M is defined by the standard or configured by eNB, and M can be positive infinity. It should be noted that the value of M can be related to the value of D3 _l . For example, when D3 _l is 100, the value of M is 1. If D3 _l is p and p is less than 100, M equals 100/p; j=0 and/or 1, the specific value is defined by the standard or configured by eNB; G3 is the initial transmission and retransmission interval field (Time in SCI 1) gap between initial transmission and retransmission); l=0,1,…,N-1, the value of each element in the set {D3 ₀ ,D3 ₁ ,D3 ₂ ,…,D3 _N-1 ,} is passed by eNB through RRC Layer signaling or physical layer signaling indication. If this is the implementation method 1, this set can represent the number of subframes corresponding to the SPS cycle that may be used by Rel-14 UEs working in mode 3 in the current resource pool. If this is the case. Situation implementation method 2: This set can represent the number of subframes corresponding to the SPS cycle that may be used by Rel-14 UEs working in mode 3 in the current resource pool, and the new subframes in mode 3 that need to be sent back to the UE to receive data. Version UE.

Method 2: If the number of subframes corresponding to the value of the resource reservation interval field (Resource reservation) in SCI ) is greater than zero, it is considered that the resources indicated by the "frequency resource location and number of included sub-channels" field on subframe m+j×G3+i×D3 are reserved, where i=0, 1,2,…,M-1, the value of M is defined by the standard or configured by eNB, and M can be positive infinity. It should be noted that the value of M can be related to the value of D3. For example, when D3 is 100, M The value is 1. If D3 is p and p is less than 100, M is equal to 100/p; j=0 and/or 1, the specific value is defined by the standard or configured by eNB; G3 is the initial transmission and retransmission interval field in SCI 1 (Time gap between initial transmission and retransmission), D3 is the number of subframes corresponding to the value of the resource reservation interval field (Resource reservation) in SCI X.

If the SCI X received by the UE in subframe m is not exactly the same as the existing SCI 1, for example, the fields included in SCI is 1, then the UE considers that the resources indicated by the "frequency resource location and number of included sub-channels" field on subframe m+j×G4+D4 are reserved, j=0 and/or 1, the specific value is determined by the standard Definition or eNB configuration; G4 is the value of the Time gap between initial transmission and retransmission field in SCI X, and D4 is the number of subframes corresponding to the value of the resource reservation gap field (Resourcereservation) in SCI X.

In _{step 302} , if SCI resource Overlaps with the _{reserved resources} indicated in SCI Then the UE excludes the single subframe resource R _{x, y} from S during resource selection or reselection. Or, for any single subframe resource R _x,y in the set S, there is a variable j∈{0,1,...,C _resel -1} such that the single subframe resource/> Overlaps with the _{reserved resources} indicated in SCI If the value prio _RX included in the priority field (Priority) _in SCI Or, for any single subframe resource R _x,y in the set S, there is a variable j∈{0,1,...,C _resel -1} such that the single subframe resource/> Overlaps with the _{reserved resources} indicated in SCI If the UE measures the PSSCH-RSRP of the PSSCH scheduled by SCI X, and the measured PSSCH-RSRP value is greater than/> or/> Where prio _TX represents the value of the priority field in the PSCCH to be sent next indicated by the UE higher layer, Δ is the value configured or pre-configured by the eNB, Th _a,b represents the SL-ThresPSSCH-RSRP- defined in the 3GPP standard 36.331V14.1.0 For the i-th SL-ThresPSSCH-RSRP in List-r14, where i=a*8+b+1, the UE excludes the single subframe resources R _{x, y} from S during resource selection or reselection.

In this case, if SCI X is type 3, the UE should measure the _PSSCH -RSRP of the PSSCH scheduled by SCI ,...,C _resel -1} makes a single subframe resource Overlaps with the _{reserved resources} indicated in SCI If the measured value of PSSCH-RSRP is greater than/> Where prio _TX represents the value of the priority field in the next PSCCH sent as indicated by the UE higher layer,/> Indicates the i-th SL-ThresPSSCH-RSRP in SL-ThresPSSCH-RSRP-List-r14 defined in 3GPP standard 36.331V14.1.0, where i=prio _TX *8+prio _RX +1, then the UE selects resources or re- Single subframe resources R _{x, y} are excluded from S when selected.

The UE may further exclude resources from set S in the manner defined in 3GPP Release 14.

The UE randomly selects a single subframe resource from the remaining resources for data transmission.

In step 303, the UE sends PSCCH on the PSCCH resource corresponding to the selected single subframe resource, and sends PSSCH on the selected single subframe resource.

For a UE working in mode 3, when sending PSCCH, the value of the priority field in the PSCCH can be set to a value lower than the priority indicated by the higher layer. Specifically, if the priority indicated by the higher layer is pr, then the UE sends The value of the priority field in the PSCCH can be set to pr-Δ, where Δ is a specific value, configured by the eNB, defined by the standard or pre-configured. In this way, UEs working in mode 3 can be better protected.

Situation three

In case three, SCI X may be type 1, type 2 or type 3. If the SCI PSSCH-RSRP, when the UE performs resource selection or reselection, for any single subframe resource in the candidate single subframe resource set S, if it overlaps with the single subframe resource reserved in SCI X, the UE should directly exclude the single subframe resource; or, if it overlaps with the single subframe resource reserved in SCI X, and the measured PSSCH-RSRP is greater than a certain threshold, the UE should exclude the single subframe resource. If the SCI X received by the UE is type 3, the UE will further measure the PSSCH-RSRP of the scheduled PSSCH after receiving the SCI If the frame resource overlaps with the single subframe resource reserved in SCI X, and the measured PSSCH-RSRP is greater than a certain threshold, the UE should exclude the single subframe resource. Proceed as follows:

In step 401, the UE detects SCI X.

In this case, if the SCI If the SCI

In step 402, if SCI The UE should exclude single subframe resources in set S that overlap with the SCI X reserved resources in the manner in Embodiment 2. No further details will be given here. The UE may further exclude resources from set S in the manner defined in 3GPP Release 14.

The UE randomly selects a single subframe resource from the remaining resources for data transmission.

In step 403, the UE sends PSCCH on the PSCCH resource corresponding to the selected single subframe resource, and sends PSSCH on the selected single subframe resource.

Situation four

In case four, the UE works in Mode 3 and SCI X is type two. When the UE receives changes in the resources allocated by the eNB signaling, for example, the data generation cycle or subframe offset indicated by SCIX changes, the UE performs channel detection at least on the resources indicated by the eNB or on part of the resources, and performs channel detection based on the detection results. Select or reselect resources. Proceed as follows:

The UE starts to perform channel detection after receiving the bypass resource allocation indication (ie, DCI 5A) sent by the eNB.

According to the first implementation method of this situation, if the single subframe resource allocated by the eNB is R _x , _y , the UE should detect the single subframe resource Where P _step represents the basic resource reservation period in the current resource pool, j=1,2,3,...I1, the value of I1 is defined by the standard, eNB configuration or pre-configuration, indicating the maximum detection period, for example, I1=10 or 1, or 5.

According to the second implementation method of this situation, if the single subframe resource allocated by the eNB is R _x,y , the UE should detect the single subframe resource Where j=1,2,3,...I2, the value of I2 is defined by the standard, eNB configuration or pre-configuration, indicating the maximum detection period, for example, I2=10, or 1, or 5. Where P _{rsvp_TX} is the current resource reservation period of the UE, and this value is indicated by the eNB.

According to the third implementation of this situation, if the single subframe resource allocated by the eNB is R _{x, y} , the UE should detect the single subframe resource R _{x, y + j × Pm} , where j = 1, 2, 3,...I3, I3 The value is defined by the standard, eNB configuration or pre-configuration, indicating the maximum detection period, for example, I2 = 10, or 1, or 5; Pm is the minimum resource reservation period supported in the current resource pool.

According to the fourth implementation of this situation, if the single subframe resource allocated by the eNB is R _{x, y} , the UE should detect subframe y. The UE receives SCI X in subframe y and the resources scheduled or reserved by this SCI j=1,2,3,... overlap, and the PSSCH-RSRP of the resource scheduled by SCI X exceeds the threshold, then the resource/> unavailable. Alternatively, the UE can also determine resources based on the S-RSSI measured in subframe y and compared with a specific threshold/> it's usable or not. The above specific thresholds are defined by standards, eNB configuration or pre-configuration. Where P _{rsvp_TX} is the current resource reservation period of the UE, and this value is indicated by the eNB.

According to the _fifth implementation of this embodiment, if the single subframe resource allocated by the _eNB is _R Configuration, indicating the maximum detection period, such as I4 = 10, or 1, or 5, to determine the resource Whether j=0,1,2,… is available. If SCIX is received and the resources scheduled or reserved by this SCIX are different from/> overlap, and the PSSCH-RSRP of the resource scheduled by SCI X exceeds the threshold, then the resource/> unavailable. Alternatively, the UE can also determine resources based on the S-RSSI measured before subframe y+I ₄ ×P _{rsvp_TX} and compared with a specific threshold/> it's usable or not. For example, for P _{rsvp_TX} =k×P _step , k=1,1/2,1/5, S-RSSI is in resource/> j=0,1,…The average value of S-RRSI measured by I4-1; for P _{rsvp_TX} =k×P _step , k>1, S-RSSI is in the resource/> j=0,1,…(I ₄ ×P _{rsvp_TX} )/P The average value of S-RRSI measured _{in step} -1. The above specific thresholds are defined by standards, eNB configuration or pre-configuration. Where P _{rsvp_TX} is the current resource reservation period of the UE, and this value is indicated by the eNB.

According to the sixth implementation of this embodiment, when the UE expects that the base station will change the period or subframe offset of the configured SPS resources, the UE starts to perform a detection operation. For example, the UE sends information about service changes to the base station, such as period changes, or changes in subframe offsets generated within the period; or the base station sends indication information to the UE, notifying the UE that the period of SPS resources may need to be changed or Subframe offset. When the UE receives the SCI X from the base station, assuming that the single subframe resource allocated by the eNB is _R Whether j=1,2,… is available. For any j value within the above j value range, if SCIX is received and the SCIX scheduled resources or reserved resources are different from overlap, and the PSSCH-RSRP of the SCIX-scheduled resource exceeds the threshold, then the resource/> unavailable. Alternatively, the UE can also determine the resource based on the measured S-RSSI before subframe y and compare it with a specific threshold. it's usable or not. For example, for P _{rsvp_TX} =k×P _step , k=1,1/2,1/5, S-RSSI is in the resource The average value of S-RRSI measured by j=0,1,...1; for P _{rsvp_TX} =k×P _step , k>1, S-RSSI is in the resource The average value of the measured S-RRSI for j=0,1,…. The above specific thresholds are defined by standards, eNB configuration or pre-configuration. Where P _{rsvp_TX} is the current resource reservation period of the UE, and this value is indicated by the eNB.

In order to support the above operations, the UE should continue to perform channel detection on all resources of each subframe in the currently selected transmission resource pool, or start performing channel detection when the UE data generation cycle changes, and report the channel detection results to the eNB. Preferably, if subframe n meets at least one of the following conditions, the UE reports the channel detection result to the eNB in subframe n:

Condition 1: The UE meets the bypass buffer status reporting (BSR) condition in subframe n, and the service corresponding to the bypass BSR is the V2X service that the UE wants to send in the current resource pool.

Condition 2: Subframe n meets the channel detection result reporting configuration indicated by eNB, that is, (n-△)mod P=0, where △ is the channel detection result reporting subframe offset indicated by eNB, and P is the channel detection result reporting period, The UE determines the value of P according to eNB instructions, preconfiguration or standard definition.

Condition 3: Subframe n is the first subframe in which the UE has uplink scheduling resources after subframe x, where subframe x is the subframe in which the UE last received a channel detection result reporting indication from the eNB. The eNB's channel detection result reporting indication may be RRC layer signaling, MAC layer signaling or physical layer signaling.

Preferably, the channel detection results reported by the UE should include the channel conditions on some or all sub-channels within the subframe range [n+a, n+b]. For any reported sub-channel, the channel conditions include the following information At least one of: the average S-RSSI on the subchannel, the PSSCH-RSRP on the subchannel, the priority of the PSSCH sent by the UE that reserves the subchannel, the resource reservation period of the UE that reserves the subchannel, etc. . For example, if the UE reports the channel detection result triggered by condition one, the values of a and b are determined by the UE implementation, and the value that satisfies b should meet the delay requirements of the UE's current service; if the UE reports the channel detection result triggered by condition two or condition Three triggers, then a=1, b=100. Because there should be at least 4ms between the subframe in which the eNB sends DCI 5A and the subframe in which the PSCCH and PSSCH resources indicated by the DCI 5A are located. Therefore, preferably, if the UE reports the channel detection result triggered by condition two or condition three, in order To provide eNB with timely channel detection results, the period P for UE reporting channel detection results should be less than b. For example, if b is 100, and the channel detection results are fed back by physical layer signaling, then the value of P should not be greater than 96; if b is 100, and the channel detection result is fed back by higher layer signaling, then the value of P should not be greater than X, where X is less than 96, for example, X=95 or 94.

Preferably, when reporting the channel detection result, the UE should further report the Global Positioning System (GPS) coordinates of the current location.

If the channel detection method is implementation method 1, and the UE is not found to occupy a single subframe resource in the I1 detections, j=1,2,3,...I1, then the UE uses the single subframe resource/> k=1,2,..., used as sending resources for data transmission.

If the channel detection mode is implementation mode 2, and the UE is not found to occupy a single subframe resource in the I2 detections, j=1,2,3,...I2, then the UE uses the single subframe resource/> k=1,2,..., used as sending resources for data transmission.

If the channel detection mode is implementation mode 3, and the single subframe resource R _x,y+j×Pm is not occupied by other UEs, j=1,2,3,…I3, then the UE determines the single subframe resource _{R I3×Pm+k×Pm} , k=1,2,…, are used as transmission resources for data transmission.

If the channel detection mode is implementation mode 4, and the single subframe resource R _{x, y} is not occupied by other UEs, the UE selects the single subframe resource j=1,2,3,..., used as sending resources for data transmission.

If the channel detection mode is implementation mode 5, and the single subframe resource j=0,1,2,…, is not occupied by other UEs, then the UE selects a single subframe resource/> Used as a sending resource for data transmission.

If the channel detection mode is implementation mode 6, and the single subframe resource R _{x, y} is not occupied by other UEs, the UE selects the single subframe resource j=1,2,3,..., used as sending resources for data transmission.

The UE sends PSCCH on the PSCCH resource corresponding to the selected single subframe resource, and sends PSSCH on the selected single subframe resource.

Situation five

In case 5, the UE works in Mode 3. Under certain conditions, the UE reports the channel detection results of the current resource pool to the eNB to assist the eNB in resource allocation. The UE working in mode 3 performs receiving operations on the resource pool, for example, receiving V2X information from other UEs and measuring CBR, so the UE can observe the service distribution on the resource pool, so that the UE can know which resources in the resource pool are relatively busy and which ones Resources are relatively idle. Therefore, mode 3 UEs can report information about resource pool service distribution to the base station, thereby assisting the base station in scheduling data transmission of mode 3 UEs on relatively idle resources, thereby reducing the impact on mode 4 users. For example, the above resource pool service distribution information may indicate the period and subframe offset of idle resources. The present invention does not limit the specific method of indicating the information of resource pool service distribution. After receiving the bypass resource allocation indication (ie, DCI 5A) sent by the eNB, the UE directly sends PSCCH and PSSCH on the resources indicated by DCI 5A, or the UE determines the sending resources according to the method described in case 4.

Preferably, a method for the UE to report detection results to assist the base station in resource allocation in mode 3 is described below. Proceed as follows:

In the first step, if subframe n meets at least one of the following conditions, the UE reports the channel detection result to the eNB in subframe n:

Condition 1: The UE meets the bypass buffer status reporting (BSR) condition in subframe n, and the service corresponding to the bypass BSR is the V2X service that the UE wants to send in the current resource pool.

Condition 2: Subframe n meets the channel detection result reporting configuration indicated by eNB, that is, (n-△)mod P=0, where △ is the channel detection result reporting subframe offset indicated by eNB, and P is the channel detection result reporting period, The UE determines the value of P according to eNB instructions, preconfiguration or standard definition.

Condition 3: Subframe n is the first subframe in which the UE has uplink scheduling resources after subframe x, where subframe x is the subframe in which the UE last received a channel detection result reporting indication from the eNB. The eNB's channel detection result reporting indication may be RRC layer signaling, MAC layer signaling or physical layer signaling.

Preferably, the channel detection results reported by the UE should include the channel conditions on some or all sub-channels within the subframe range [n+a, n+b]. For any reported sub-channel, the channel conditions include the following information At least one of: the average S-RSSI on the subchannel, the PSSCH-RSRP on the subchannel, the priority of the PSSCH sent by the UE that reserves the subchannel, the resource reservation period of the UE that reserves the subchannel, etc. . For example, if the UE reports the channel detection result triggered by condition one, the values of a and b are determined by the UE implementation, and the value that satisfies b should meet the delay requirements of the UE's current service; if the UE reports the channel detection result triggered by condition two or condition Three triggers, then a=1, b=100. Because there should be at least 4ms between the subframe in which the eNB sends DCI 5A and the subframe in which the PSCCH and PSSCH resources indicated by the DCI 5A are located. Therefore, preferably, if the UE reports the channel detection result triggered by condition two or condition three, in order To provide eNB with timely channel detection results, the period P for UE reporting channel detection results should be less than b. For example, if b is 100, and the channel detection results are fed back by physical layer signaling, then the value of P should not be greater than 96; if b is 100, and the channel detection result is fed back by higher layer signaling, then the value of P should not be greater than X, where X is less than 96, for example, X=95 or 94.

Preferably, when reporting the channel detection result, the UE should further report the Global Positioning System (GPS) coordinates of the current location.

In the second step, after receiving the bypass resource allocation indication (ie, DCI 5A) sent by the eNB, the UE sends PSCCH and PSSCH on the resources indicated by DCI 5A or on the transmission resources determined according to the method in case 4.

Through the above method, the UE working with Mode 3 determines the resource occupation and resource reservation in the current resource pool through channel detection. After the UE reports the detection results to the eNB, the eNB can schedule resources with relatively high channel quality to mode 3UE data transmission, thereby reducing the mutual influence between Mode 3 and mode 4 users.

Figure 2 is a block diagram of a user equipment (UE) that performs a resource selection or reselection method in vehicle-to-external V2X communication according to an embodiment of the present invention. Referring to FIG. 2 , the device includes: a detection module 21 , a resource selection or reselection module 22 and a sending module 23 .

The detection module is used to detect PSCCH sent by other UEs. The detection module may detect SCI X on all PSCCH resources in the transmission resource pool currently selected by the UE, or only detect SCI The location of the resource.

The resource selection or reselection module is configured to select a single subframe resource among single subframe resources that do not overlap with the detected single subframe resource reserved by the PSCCH.

According to an embodiment of the present invention, if the detected SCI

According to another embodiment _of the present invention, if the detected SCI Single subframe resources are selected from single subframe resources that do not overlap.

For example, the specific PSCCH format is SCI 1 defined in 3GPP Release 14, or a PSCCH format different from SCI 1 defined in 3GPP Release 14, or has the same number of bits as SCI 1 defined in 3GPP Release 14, and each The meaning of the fields is the same, but one or more bits in the reserved bit field are 1.

According to another embodiment of the present invention, the resource selection or reselection module further measures the bypass reference signal received power (PSSCH-RSRP) of the PSSCH scheduled by SCI X. If the PSSCH-RSRP is higher than a specific threshold, then Select a single subframe resource from the single subframe resources that do not overlap with the detected single subframe resources reserved by the PSCCH.

The sending module sends the physical bypass shared channel PSSCH on the selected single subframe resource.

Those skilled in the art will appreciate that the present invention includes devices for performing one or more of the operations described in this application. These devices may be specially designed and manufactured for the required purposes, or they may include devices known from general purpose computers. These devices have computer programs stored within them that are selectively activated or reconfigured. Such computer program may be stored on a device (eg, computer) readable medium or in any type of medium suitable for storing electronic instructions and respectively coupled to a bus, including, but not limited to, any Types of disks (including floppy disks, hard disks, optical disks, CD-ROMs, and magneto-optical disks), ROM (Read-Only Memory, read-only memory), RAM (Random Access Memory, random memory), EPROM (Erasable ProgrammableRead-Only Memory, Erasable programmable read-only memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), flash memory, magnetic card or light card. That is, readable media includes any medium that stores or transmits information in a form that can be read by a device (eg, a computer).

It will be understood by those skilled in the art that computer program instructions may be used to implement each block in the structural diagrams and/or block diagrams and/or flow diagrams, and combinations of blocks in the structural diagrams and/or block diagrams and/or flow diagrams. . Those skilled in the art can understand that these computer program instructions can be provided to a processor of a general-purpose computer, a professional computer or other programmable data processing methods for implementation, so that the present invention is executed by the processor of a computer or other programmable data processing methods. The invention discloses solutions specified in a block or multiple blocks of a structure diagram and/or a block diagram and/or a flow diagram.

Those skilled in the art can understand that the steps, measures, and solutions in the various operations, methods, and processes that have been discussed in the present invention can be alternated, changed, combined, or deleted. Furthermore, other steps, measures, and solutions in the various operations, methods, and processes that have been discussed in the present invention can also be alternated, changed, rearranged, decomposed, combined, or deleted. Furthermore, the steps, measures, and solutions in the various operations, methods, and processes disclosed in the present invention in the prior art can also be alternated, changed, rearranged, decomposed, combined, or deleted.

The above are only some embodiments of the present invention. It should be pointed out that those skilled in the art can also make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications can also be made. should be regarded as the protection scope of the present invention.

Claims (24)

1. A method performed by a terminal in a wireless communication system, the method comprising: Receive configuration information about the bypass resource pool from the base station; performing channel detection on the bypass resource pool based on parameters associated with the channel detection; and Report the channel detection results to the base station, Wherein, the parameters associated with the channel detection include at least one of a resource reservation period and a priority of the physical bypass shared channel PSSCH. 2. The method of claim 1, wherein reporting the channel detection result to the base station includes: When the result of the channel detection is available, report the result of the channel detection to the base station based on the configuration information associated with the reporting of the result of the channel detection, The configuration information associated with the reporting of channel detection results includes a reporting period of channel detection results. 3. The method of claim 1 or 2, further comprising: Receive configuration information associated with reporting of channel detection results from the base station. 4. The method of claim 1, wherein the terminal is configured in bypass transmission mode 3. 5. The method of claim 1, wherein parameters associated with channel detection are configured by the base station. 6. The method of claim 1, wherein reporting the channel detection result to the base station further includes: Periodically report channel detection results to the base station; The period for reporting channel detection results is configured by the base station. 7. A terminal in a wireless communication system, including: transceiver; and At least one processor, configured as: Receive configuration information about the bypass resource pool from the base station, perform channel detection on the bypass resource pool based on parameters associated with the channel detection, and Report the channel detection results to the base station, Wherein, the parameters associated with the channel detection include at least one of a resource reservation period and a priority of the physical bypass shared channel PSSCH. 8. The terminal of claim 7, wherein the at least one processor is further configured to: When the result of the channel detection is available, report the result of the channel detection to the base station based on the configuration information associated with the reporting of the result of the channel detection, The configuration information associated with the reporting of channel detection results includes a reporting period of channel detection results. 9. The terminal of claim 7 or 8, wherein the at least one processor is further configured to: Receive configuration information associated with reporting of channel detection results from the base station. 10. The terminal of claim 7, wherein the terminal is configured in bypass transmission mode 3. 11. The terminal of claim 7, wherein parameters associated with channel detection are configured by the base station. 12. The terminal of claim 7, wherein the at least one processor is further configured to: Periodically report the channel detection results to the base station, The period for reporting channel detection results is configured by the base station. 13. A method performed by a base station in a wireless communication system, the method comprising: Send configuration information about the bypass resource pool to the terminal; and Receive from the terminal the result of performing channel detection on the bypass resource pool, wherein the channel detection is performed based on parameters associated with the channel detection, and Wherein, the parameters associated with the channel detection include at least one of a resource reservation period and a priority of the physical bypass shared channel PSSCH. 14. The method of claim 13, wherein receiving from the terminal a result of performing channel detection on the bypass resource pool comprises: receiving the result of the channel detection reported based on the configuration information associated with the reporting of the result of the channel detection when the result of the channel detection is available, The configuration information associated with the reporting of channel detection results includes a reporting period of channel detection results. 15. The method of claim 13 or 14, further comprising: Send configuration information associated with reporting of channel detection results to the terminal. 16. The method of claim 13, wherein the terminal is configured in bypass transmission mode 3. 17. The method of claim 13, wherein the method further comprises configuring parameters associated with channel detection for the terminal. 18. The method of claim 13, wherein receiving from the terminal a result of performing channel detection on the bypass resource pool comprises: Periodically receiving from the terminal the results of performing channel detection on the bypass resource pool, Wherein, the method further includes: configuring a period for reporting channel detection results for the terminal. 19. A base station in a wireless communication system, including: transceiver; and At least one processor, configured as: Send configuration information about the bypass resource pool to the terminal, and Receive from the terminal the result of performing channel detection on the bypass resource pool, wherein the channel detection is performed based on parameters associated with the channel detection, and Wherein, the parameters associated with the channel detection include at least one of a resource reservation period and a priority of the physical bypass shared channel PSSCH. 20. The base station of claim 19, wherein the at least one processor is further configured to: receiving the result of the channel detection reported based on the configuration information associated with the reporting of the result of the channel detection when the result of the channel detection is available, The configuration information associated with the reporting of channel detection results includes a reporting period of channel detection results. 21. The base station of claim 19 or 20, wherein the at least one processor is further configured to: Send configuration information associated with reporting of channel detection results to the terminal. 22. The base station of claim 19, wherein the terminal is configured in bypass transmission mode 3. 23. The base station of claim 19, wherein the at least one processor is further configured to configure parameters associated with channel detection for the terminal. 24. The base station of claim 19, wherein the at least one processor is further configured to: Configure the period for reporting channel detection results for the terminal, and The results of channel detection performed on the bypass resource pool are periodically received from the terminal.