Method and apparatus for sidelink communication

Abstract

The application provides a method and device for sidelink communication. The method comprises: a terminal device performs channel listening on a shared spectrum; if the result of the channel listening is that the channel is idle, the terminal device starts transmitting a first sidelink channel at a first time domain position; wherein the first time domain position is one or more of: a time domain position indicated by first indication information; a time domain position determined based on a first time unit, wherein the first time unit is less than one time slot.

Description

[0001] This application is a divisional application of application No. 202210993192.5, titled "Method and apparatus for sidelink communication", filed on August 18, 2022. TECHNICAL FIELD

[0002] The present application relates to the technical field of communication, more particularly, to a method and apparatus for sidelink communication. BACKGROUND

[0003] When performing sidelink communication in a shared spectrum, a terminal device performs channel listening through mechanisms such as listen before talk (LBT). In the case of successful channel listening, the terminal device obtains channel resources and performs sidelink transmission at a channel access position. In related technologies, the process of channel access by the terminal device causes waste of channel resources. SUMMARY

[0004] The present application provides a method and apparatus for sidelink communication, which helps to reduce resource waste of sidelink communication.

[0005] In a first aspect, a method for sidelink communication is provided, comprising: a terminal device performing channel listening in a shared spectrum; if the result of the channel listening is that the channel is idle, the terminal device starts to transmit a first sidelink channel at a first time domain position; wherein the first time domain position is one or more of: a time domain position indicated by first indication information; a time domain position determined based on a first time unit, wherein the first time unit is less than one time slot.

[0006] In a second aspect, a method for sidelink communication is provided, comprising: a terminal device performing channel access on a first resource in a shared spectrum, wherein the first resource is associated with a second resource in a resource pool; and the terminal device transmitting a first sidelink channel on the second resource.

[0007] In a third aspect, an apparatus for sidelink communication is provided, the apparatus being a terminal device, and the apparatus comprising: a listening unit configured to perform channel listening in a shared spectrum; and a transmission unit configured to start to transmit a first sidelink channel at a first time domain position if the result of the channel listening is that the channel is idle; wherein the first time domain position is one or more of: a time domain position indicated by first indication information; a time domain position determined based on a first time unit, wherein the first time unit is less than one time slot.

[0008] In a fourth aspect, a device for sidelink communication is provided. The device is a terminal device. The device includes an access unit configured to perform channel access on a first resource of a shared spectrum, wherein the first resource is associated with a second resource of a resource pool; and a transmission unit configured to transmit a first sidelink channel on the second resource.

[0009] In a fifth aspect, a communication device is provided. The device includes a memory configured to store a program and a processor configured to invoke the program in the memory to perform the method of the first aspect or the second aspect.

[0010] In a sixth aspect, a device is provided. The device includes a processor configured to invoke a program in a memory to perform the method of the first aspect or the second aspect.

[0011] In a seventh aspect, a chip is provided. The chip includes a processor configured to invoke a program in a memory to cause a device in which the chip is installed to perform the method of the first aspect or the second aspect.

[0012] In an eighth aspect, a computer-readable storage medium is provided. The computer-readable storage medium has a program stored thereon. The program causes a computer to perform the method of the first aspect or the second aspect.

[0013] In a ninth aspect, a computer program product is provided. The computer program product includes a program. The program causes a computer to perform the method of the first aspect or the second aspect.

[0014] In a tenth aspect, a computer program is provided. The computer program causes a computer to perform the method of the first aspect or the second aspect.

[0015] After the terminal device successfully performs channel listening, the terminal device can perform sidelink transmission at a first time domain position specified by the terminal device or determined based on a time unit smaller than a time slot. Thus, the terminal device can perform sidelink transmission without waiting for a next time slot after successfully performing channel listening, thereby helping to reduce waste of channel resources. BRIEF DESCRIPTION OF DRAWINGS

[0016] FIG. 1 is a wireless communication system to which embodiments of the present application are applied.

[0017] FIG. 2 is a communication example diagram of NR-V2X.

[0018] FIG. 3 is a schematic diagram of a full-slot channel access mode.

[0019] FIG. 4 is a schematic diagram of three channel access modes in NR-U.

[0020] FIG. 5is a schematic diagram of resource collision of channel access.

[0021] FIG. 6 is a schematic flow chart of a method of sidelink communication provided by an embodiment of the present application.

[0022] FIG. 7 is a schematic diagram of a designated location channel access method provided by an embodiment of the present application.

[0023] FIG. 8 is a schematic diagram of a half-slot channel access method provided by an embodiment of the present application.

[0024] FIG. 9 is a schematic diagram of a more fine channel access method provided by an embodiment of the present application.

[0025] FIG. 10 is a schematic flow chart of another method of sidelink communication provided by an embodiment of the present application.

[0026] FIG. 11 is a schematic diagram of association of a first resource and a second resource provided by an embodiment of the present application.

[0027] FIG. 12 is a schematic diagram of association of another first resource and a second resource provided by an embodiment of the present application.

[0028] FIG. 13 is a schematic block diagram of a communication apparatus provided by an embodiment of the present application.

[0029] FIG. 14 is a schematic block diagram of another communication apparatus provided by an embodiment of the present application.

[0030] FIG. 15 is a schematic structural diagram of a communication apparatus provided by an embodiment of the present application. DETAILED DESCRIPTION

[0031] The technical solutions in the present application will be described below with reference to the accompanying drawings. In order to facilitate understanding, the following will first be described with reference to the accompanying drawings FIGS. 1-5 introduce the terms and communication processes involved in the present application.

[0032] FIG. 1 is an example diagram of system architecture of a wireless communication system 100 to which embodiments of the present application are applicable. The wireless communication system 100 can include a network device 110 and terminal devices 121-129. The network device 110 can provide communication coverage for a specific geographic area, and can communicate with terminals located in the coverage area.

[0033] In some implementations, terminal devices can communicate with each other through sidelink (SL). Sidelink communication can also be referred to as proximity services (ProSe) communication, one-sided communication, side chain communication, device to device (D2D) communication, etc.

[0034] In other words, terminal devices communicate sidelink data through sidelink. The sidelink data can include data and / or control signaling. In some implementations, the sidelink data can be, for example, a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), a PSCCH demodulation reference signal (DMRS), a PSSCH DMRS, a physical sidelink feedback channel (PSFCH), etc.

[0035] The following describes FIG. 1 Several common sidelink communication scenarios are introduced. In sidelink communication, according to whether the terminal devices in the sidelink are within the coverage of the network device, three scenarios can be divided. Scenario 1: terminal devices perform sidelink communication within the coverage of the network device. Scenario 2: some terminal devices perform sidelink communication within the coverage of the network device. Scenario 3: terminal devices perform sidelink communication outside the coverage of the network device.

[0036] As shown in FIG. 1 In scenario 1, terminal devices 121-122 can communicate through sidelink, and terminal devices 121-122 are both within the coverage of network device 110, or in other words, terminal devices 121-122 are both within the coverage of the same network device 110. In this scenario, network device 110 can send configuration signaling to terminal devices 121-122, and accordingly, terminal devices 121-122 communicate through sidelink based on the configuration signaling.

[0037] As shown in FIG. 1As shown, in scenario 2, terminal devices 123 and 124 can communicate via the sidelink, with terminal device 123 within the coverage area of ​​network device 110 and terminal device 124 outside the coverage area of ​​network device 110. In this scenario, terminal device 123 receives configuration information from network device 110 and communicates via the sidelink based on the configuration signaling. However, for terminal device 124, since it is outside the coverage area of ​​network device 110, it cannot receive the configuration information from network device 110. In this case, terminal device 124 can obtain the sidelink communication configuration based on the pre-configuration configuration information and / or the configuration information sent by terminal device 123 within the coverage area, so as to communicate with terminal device 123 via the sidelink based on the obtained configuration.

[0038] In some cases, terminal device 123 can send the above configuration information to terminal device 124 through the physical sidelink broadcast channel (PSBCH) to configure terminal device 124 to communicate through the sidelink.

[0039] like FIG. 1 As shown, in scenario 3, terminal devices 125-129 are all outside the coverage area of ​​network device 110 and cannot communicate with network device 110. In this case, the terminal devices can all perform sidelink communication based on pre-configured information.

[0040] In some cases, terminal devices 127-129 located outside the coverage area of ​​network equipment can form a communication group, and terminal devices 127-129 within the communication group can communicate with each other. In addition, terminal device 127 within the communication group can act as a central control node, also known as the cluster header (CH), and correspondingly, other terminal devices within the communication group can be referred to as "group members".

[0041] As a terminal device 127 of CH, it may have one or more of the following functions: responsible for establishing communication groups; joining and leaving groups; coordinating resources, allocating side-transmission resources to group members, receiving side-transmission feedback information from group members, and coordinating resources with other communication groups.

[0042] It should be noted that, FIG. 1 An exemplary embodiment shows a network device and multiple terminal devices. Optionally, the wireless communication system 100 may include multiple network devices and each network device may include other numbers of terminal devices within its coverage area. This application embodiment does not limit this.

[0043] Optionally, the wireless communication system 100 can further include other network entities such as a network controller, a mobility management entity, etc., which are not limited herein by the embodiments of the present application.

[0044] It should be understood that the technical solutions of the embodiments of the present application can be applied to various communication systems, for example, a 5th generation (5G) system or a new radio (NR) system, a long term evolution (LTE) system, an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD) system, etc. The technical solutions provided by the present application can also be applied to future communication systems, such as a 6th generation mobile communication system, a satellite communication system, etc.

[0045] The terminal device in the embodiments of the present application can also be referred to as a user equipment (UE), an access terminal, a user unit, a user station, a mobile station, a mobile station (MS), a mobile terminal (MT), a remote station, a remote terminal, a mobile device, a user terminal, a wireless communication device, a user agent or a user apparatus. The terminal device in the embodiments of the present application can be a device that provides voice and / or data connectivity for a user in a communication network, and can be used for connecting people, things and machines, such as a handheld device with wireless connectivity, a vehicle-mounted device, etc. The terminal device in the embodiments of the present application can be a mobile phone, a tablet computer (Pad), a notebook computer, a palm computer, a mobile internet device (MID), a wearable device, a vehicle, a wireless terminal in industrial control, a wireless terminal in self driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc. Optionally, the terminal device can be used to act as a base station. For example, the terminal device can act as a scheduling entity, which provides a sidelink signal between terminal devices in vehicle-to-everything (V2X) or D2D, etc. For example, a cellular phone and a car communicate with each other using sidelink data. A cellular phone and a smart home device communicate with each other without relaying a communication signal through a base station.

[0046] The network device in the embodiments of the present application can be a device for communicating with a terminal device, and the network device can also be referred to as an access network device or a radio access network device, for example, the network device can be a base station. The network device in the embodiments of the present application can refer to a radio access network (RAN) node (or device) for accessing a terminal device to a wireless network. The base station can broadly cover various names in the following or be replaced by the following names, such as: Node B (NodeB), evolved Node B (eNB), next generation Node B (gNB), relay station, transmitting and receiving point (TRP), transmitting point (TP), access point (AP), master station MeNB, auxiliary station SeNB, multi-standard radio (MSR) node, home base station, network controller, access node, wireless node, transmission node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), positioning node, etc. The base station can be a macro base station, a micro base station, a relay node, a donor node or the like, or a combination thereof. The base station can also refer to a communication module, modem or chip for being arranged in the foregoing device or apparatus. The base station can also be a mobile switching center and a device assuming a base station function in D2D, V2X, machine-to-machine (M2M) communication, a network side device in 6G network, a device assuming a base station function in future communication system, etc. The base station can support networks of the same or different access technologies. The embodiments of the present application do not limit the specific technology and specific device form of the network device.

[0047] The base station can be fixed or mobile. For example, a helicopter or a drone can be configured to act as a mobile base station, and one or more cells can move according to the location of the mobile base station. In other examples, the helicopter or the drone can be configured to act as a device communicating with another base station.

[0048] In some deployments, the network device in the embodiments of the present application can refer to a CU or a DU, or the network device includes a CU and a DU. The gNB can also include an AAU.

[0049] The network device and the terminal device can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; can also be deployed on water; and can also be deployed on airplanes, balloons and satellites in the air. The scene where the network device and the terminal device are located is not limited in the embodiments of the present application.

[0050] It should be understood that all or part of the functions of the communication device in the present application can also be implemented by software functions running on hardware, or by virtualized functions instantiated on a platform (such as a cloud platform).

[0051] With the development of sidelink communication technology, sidelink communication technology involves information interaction of multiple terminal devices. For example, as shown in the V2X communication system 200, the vehicle-to-vehicle (V2V) communication between the terminal device 201 and the terminal device 202 involves information interaction between vehicles themselves. The vehicle-to-infrastructure (V2I) communication, vehicle-to-network (V2N) communication and vehicle-to-pedestrian (V2P) communication between the terminal device 201 and the terminal devices 203-205 respectively involve information interaction between vehicles and external systems. FIG. 2

[0052] Communication spectrum for sidelink

[0053] The frequency spectrum used by the communication system includes licensed frequency spectrum and unlicensed frequency spectrum. An important direction of the expansion of the communication system to different fields is to use unlicensed frequency spectrum. For example, NR deployed on unlicensed frequency spectrum is referred to as NR-U.

[0054] At present, the main frequency spectrum used by sidelink is licensed frequency spectrum. Sidelink can also use unlicensed frequency spectrum. Deploying sidelink on unlicensed frequency spectrum can be referred to as SL-U.

[0055] Compared with licensed frequency spectrum, unlicensed frequency spectrum has a shared characteristic of not requiring permission, so unlicensed frequency spectrum is also referred to as shared frequency spectrum. For an operator, spectrum sharing helps to aggregate spectrum in time to dynamically support high-bandwidth services. Spectrum sharing can also extend the advantages of communication technology (for example, NR) to operators who may not be able to obtain licensed frequency spectrum.

[0056] ​The shared spectrum needs to consider the coexistence between different radio access technology (RAT) systems, such as a wireless fidelity (WiFi) system, a license assisted access (LAA) system based on LTE, and the like. Different systems use the frequency band in the unlicensed spectrum in a competitive manner according to the principles of channel access fairness and multi-RAT coexistence.

[0057] In the shared spectrum, any RAT system needs to communicate under the limitation of unlicensed spectrum regulatory rules. The regulatory rules include power and power spectral density levels, maximum channel occupancy time (COT), channel occupancy bandwidth, channel listening mechanism, and the like. In the same frequency band, each system needs to meet the requirements of the regulatory rules, reasonably occupy and release the channel, so as to not cause interference to other RAT systems in the same frequency band.

[0058] For the use of the shared spectrum, the RAT system can use a mandatory channel listening technology (for example, LBT) to access the network. That is, data transmission can be performed only when it is detected that the current channel is not occupied. For example, the terminal device of the sidelink can initiate LBT, which can be Cat 1 LBT or Cat 2 LBT.

[0059] After the terminal device obtains the channel resource through LBT, data transmission is performed based on the above regulatory rules. For example, when the terminal device performs data transmission through the channel resource, the COT limitation needs to be met. That is, a continuous data transmission is limited within the COT time, and the terminal device needs to release the channel and perform LBT again if the time exceeds.

[0060] Sidelink resource allocation approaches

[0061] The resource allocation manner can be determined based on the service type of the terminal device. The services of the sidelink terminal device mainly include two types: periodic services and aperiodic services. For the periodic services, the sidelink data of the terminal device usually has periodicity. For example, in the road safety service of NR V2X, part of the sidelink data is periodic traffic that can arrive at a predictable time. For the aperiodic services, the arrival of data is random, and the size of the data packet is variable.

[0062] In some communication systems (for example, NR), two resource configuration manners of sidelink resources are defined, mode 1 and mode 2.

[0063] Mode 1, sidelink resources are scheduled for terminal devices by a network device.

[0064] Currently, in mode 1, there are two ways: dynamic resource allocation and sidelink configured grant. In dynamic resource allocation, the network device can allocate sidelink transmission resources for terminal devices by sending downlink control information (DCI). In the sidelink configured grant mode, when the terminal device is configured with sidelink resources, if the terminal device has data to be sent, the terminal device can use the configured sidelink resources to transmit data without reapplying for sidelink resources from the network device. For periodic traffic, the network device usually allocates semi-static transmission resources for terminal devices. The network device can effectively avoid resource conflicts and solve the hidden node problem by scheduling terminal devices to transmit on the sidelink.

[0065] For example, referring to FIG. 1 , terminal devices 121-123 are located within the coverage of network device 110, and network device 110 can allocate sidelink resources to terminal devices 121-123.

[0066] Mode 2, terminal devices autonomously select sidelink resources in a sidelink resource pool.

[0067] This mode uses a distributed resource scheduling mechanism. The sidelink resource pool can be configured by the network device or preconfigured. In some embodiments, the network device can configure the sidelink resource pool to the terminal device through high-layer signaling. The terminal device selects the time-frequency resource in the network device configured or preconfigured resource pool by relying on resource sensing or random selection. For example, FIG. 1 terminal devices 124-129 in are located outside the coverage of network device 110, and terminal devices 124-129 can autonomously select sidelink resources in the network device configured resource pool, respectively.

[0068] In periodic traffic, the sidelink can reserve (or pre-reserve) resources for sidelink communication for terminal devices at the expected time of data arrival to avoid resource competition with other terminal devices. For example, the terminal devices of the sidelink can support resource reservation for periodic traffic by indicating the reservation period in the sidelink control information (SCI).

[0069] In mode 2, for periodic traffic, the terminal device can perform a sensing channel and resource allocation mechanism combined with semi-persistent scheduling (SPS). This mechanism can take full advantage of the periodicity of the traffic, and the sending end can reserve periodic transmission resources to carry the periodic traffic to be sent, which helps the receiving end to perform resource state sensing and collision avoidance, and improves the resource utilization and transmission reliability.

[0070] For aperiodic traffic, the terminal device performs a resource allocation mechanism combined with single transmission based on sensing. Since the future resource occupation cannot be predicted and reserved, the probability of resource collision is relatively large.

[0071] The process of sensing the channel by the terminal device includes a resource sensing process and / or a resource selection process. Resource sensing can also be referred to as resource listening or resource detection. The terminal device performs resource sensing and selection based on a dedicated sidelink resource pool, which can alleviate or avoid potential resource conflicts between terminal devices. For example, the terminal device can select a sidelink transmission resource in the resource pool through sensing.

[0072] In the resource sensing process, the terminal device can identify the occupation (or reservation) of the sidelink resource by demodulating the SCI, i.e., the terminal device can obtain the resource reservation information of other terminal devices by demodulating the SCI. The terminal device can also identify the occupation of the sidelink resource by measuring the received power of the sidelink.

[0073] After the terminal device reserves the transmission resource for periodic traffic, all other terminal devices receiving the reservation message will avoid selecting and transmitting on the reserved resource. In some embodiments, the terminal device can select a resource from the resource pool that is not reserved by other terminal devices or is reserved by other terminal devices but has low received power, thereby reducing the probability of resource collision and improving communication reliability.

[0074] The resource allocation mechanism of mode 2 works well in licensed or dedicated spectrum (frequency band). However, in unlicensed spectrum, the resource allocation mechanism of mode 2 has some limitations.

[0075] In one aspect, the mode 2 resource allocation manner needs to consider the uncertainty of channel sensing when applied to SL-U. Due to the dependence on the channel sensing result, it is difficult for sidelink to reserve resources at a specific time. At present, the sidelink reserves a time window in the unlicensed channel. The time window can be composed of a set of time slots. These time slots occur periodically. The time window starts approximately before the expected data arrival time to avoid possible channel sensing failure. The resources reserved during the time window can be a set of time and frequency interleaved resource blocks (RBs). These resource blocks can be used as the required resources for channel access.

[0076] On the other hand, there are a large number of other types of RAT devices in the unlicensed spectrum, such as WiFi devices, LAA devices, enhanced license assisted access (eLAA) devices, and NR-U devices. The channel resources required by the sidelink can not only be occupied by the terminal devices of the sidelink, but also be occupied by other types of RAT devices. The traditional mode 2 process cannot identify and solve the resource conflict caused by non-sidelink terminal devices, which may cause channel sensing failure of the sidelink terminal devices.

[0077] Further, the resource reservation of the sidelink terminal device is invalid for other types of RAT devices. These devices cannot listen to the reservation message sent by the sidelink terminal device, nor can they receive and understand the resource reservation information in the SCI. These devices will try to occupy the channel overlapping with the reserved resources, and will continuously perform CCA on the reserved resources. For other terminal devices that follow the reservation, the opportunity to obtain CCA success is reduced, and the efficiency of SL-U using the traditional mode 2 is reduced. Therefore, mode 2 resource selection is more useful when there are no traditional devices nearby.

[0078] When the sidelink terminal device operates within the network coverage, the terminal devices nearby will also not listen to the reservation message. In order to reduce the conflict of reserved resources, the sidelink terminal device can forward the reservation signal to the network device, and the network device can avoid scheduling uplink transmission on the reserved resources.

[0079] Under mode 2, the terminal device determines the transmission resources of the corresponding PSCCH / PSSCH and PSFCH by performing a resource selection procedure. On the unlicensed spectrum, the terminal device generally starts to perform resource selection after the channel sensing is successful. Unlike NR-U, the terminal device of the sidelink must be able to perform multi-channel access by itself, rather than being scheduled or instructed.

[0080] Channel access for sidelink

[0081] After the terminal device detects that the channel is idle through the channel listening mechanism such as LBT, the terminal device performs channel access on the idle resource to transmit data. Therefore, the listening avoidance mechanism such as LBT is also called a channel access mechanism.

[0082] In some protocols (R16 / R17), a terminal device supporting sidelink performs channel access in units of slots, that is, full-slot channel access. The length of a slot is related to a subcarrier spacing. In some communication systems (for example, NR), multiple subcarrier spacings can be supported, and the radio frame structure is slightly different according to the subcarrier spacing. The length of a radio frame and a subframe does not change with the change of the subcarrier spacing. The length of a radio frame is always 10 ms, and the length of a subframe is always 1 ms.

[0083] A subframe is composed of one or more slots, and the length of a slot is related to the subcarrier spacing. For example, when the subcarrier spacing is 15 kHz, the length of a slot is 1 ms, which is the same as the length of a subframe. When the subcarrier spacing is 30 kHz, the length of a slot is 0.5 ms, and two slots make up a subframe. However, the number of symbols in a slot does not change with the change of the subcarrier spacing, but only changes with the configuration type of the slot. Generally, one slot contains 14 symbols.

[0084] In full-slot channel access containing 14 symbols, the terminal device takes every 14 symbols as a transmission starting point based on a synchronized time point. The transmission starting point can also be called a channel access position. In this way, no matter at which time point the terminal device performs channel listening, after the listening is successful, the terminal device needs to wait for the next transmission starting point to perform channel access. That is, after the terminal device successfully performs channel listening, the terminal device needs to wait for the next slot to perform data transmission.

[0085] The full-slot channel access mode will be described below in combination with FIG. 3 an example in which a terminal device transmits PSCCH / PSSCH through LBT.

[0086] Referring to FIG. 3 , the terminal device completes LBT at an early stage of slot 310. In the full-slot channel access mode, the terminal device needs to wait for slot 320 to perform transmission of PSCCH / PSSCH. As shown in FIG. 3 , the transmission starting point is located at the start of slot 320. In slot 320, the first symbol is used as an automatic gain control (AGC) symbol, and the data on the AGC symbol is generally not used for data demodulation. The last symbol is a guard interval (GAP) symbol. Between AGC and GAP is PSCCH / PSSCH. In the sidelink, a slot basically does not carry uplink or downlink link symbols.

[0087] Compared to time slot 320, only a few symbols in time slot 310 are used for the LBT (Local Bit By-Break) of the terminal equipment. The terminal equipment cannot utilize the symbols between the LBT and the transmission start point in time slot 310. Therefore, the resources of several symbols in time slot 310 are wasted.

[0088] like FIG. 3 As shown, after LBT is completed in time slot 310, the terminal device performs data transmission in time slot 320. Since the availability of the channel in the shared spectrum cannot be guaranteed at all times, the terminal device needs to perform a clear channel assessment (CCA) before data transmission to ensure the channel is idle. For example, the terminal device can measure the channel energy on the LBT bandwidth (BW) based on a 20MHz RB set.

[0089] In unlicensed spectrum, channel assessment before data transmission includes various channel access methods. The following section combines... FIG. 4 The three channel access methods of NR-U are described, and the channel access process before data transmission is explained. (See also...) FIG. 4 Both Type 2A and Type 2B have a channel sensing interval during channel access, while Type 2C does not require channel sensing.

[0090] by FIG. 4 Taking channel access of type 2A as an example, after the terminal device senses that the channel (medium) is idle according to an appropriate energy detection threshold, there is a delay period before SL transmission. FIG. 4 The delay period for type 2A is 25 μs. For example... FIG. 4 As shown, the 25μs delay period mainly includes a 16μs delay time and a 9μs contention slot. The terminal device performs clear CCA during the contention slot. The delay period avoids conflicts with potential WiFi confirmation time (16μs) and also allows the terminal device preparation time.

[0091] In Type 2A channel access, the 9μs contention slot can also be called a short-time LBT or an additional LBT. The delay period of channel access can be adjusted by setting a certain number of additional LBTs. Therefore, the minimum length of the delay period in Type 2A is 25μs.

[0092] When channel access is based on Type 2A, once the terminal device is ready, the additional LBT can be cleared and the transmission can be started directly. If the terminal device is not ready after the delay period countdown is completed, the channel access will be declared as failed and the procedure should be restarted. In some cases, a device from another RAT can complete its LBT and start transmission before the next transmission start point of the SL-U terminal device. The additional LBT allows the SL-U terminal device to detect this situation and delay the access. For example, FIG. 3 When the terminal device clears the additional short LBT, a WiFi node has cleared its LBT before the transmission start point, the WiFi node will occupy the channel. Therefore, the transmission resource collides and the terminal device of the SL-U fails to access.

[0093] When channel access is based on Type 2A, once the terminal device is ready, the additional LBT can be cleared and the transmission can be started directly. If the terminal device is not ready after the delay period countdown is completed, the channel access will be declared as failed and the procedure should be restarted. In some cases, a device from another RAT can complete its LBT and start transmission before the next transmission start point of the SL-U terminal device. The additional LBT allows the SL-U terminal device to detect this situation and delay the access. For example,

[0094] The above describes the current channel access mode of the sidelink as full-time slot channel access. In a time slot, there are multiple terminal devices performing channel listening. If multiple terminal devices all successfully listen in this time slot, multiple terminal devices all need to wait for the next time slot to perform data transmission. Therefore, multiple terminal devices can cause resource collision at the transmission start point of the next time slot.

[0095] The following takes the channel access procedure of Type 2A as an example, and describes in detail the situation of resource collision of channel access. FIG. 5

[0096] Referring to FIG. 5 , the terminal device 1 and the terminal device 2 both perform LBT in the time slot 510. The terminal device 1 completes LBT in the early stage of the time slot 510 and needs to wait for the time slot 520 to perform PSCCH / PSSCH transmission. In the process of waiting for the terminal device 1, the terminal device 2 also completes LBT in the late stage of the time slot 510. Both terminal devices need to perform PSCCH / PSSCH transmission in the time slot 520.

[0097] Before the transmission start point shown in FIG. 5 , both terminal devices determine whether the channel is idle through short additional LBT. After determining that the channel is idle in the contention period of the additional LBT, the terminal device 1 or the terminal device 2 can access the channel and perform data transmission.

[0098] As​FIG. 5 As shown in FIG. 6, after the terminal device 1 and the terminal device 2 complete the countdown part of LBT in the time slot 510, resource collision occurs between the two terminal devices in the additional LBT before the aligned transmission starting point.

[0099] FIG. 3 The resource waste and FIG. 5 The resource collision is caused by the fact that the sidelink performs channel access in time slots. After the terminal device succeeds in channel listening, the terminal device needs to wait for the next time slot to perform channel access, and the waiting time interval is relatively long.

[0100] Based on this, the embodiments of the present application provide a sidelink communication method and device. The time slot structure of the method provides a more flexible channel access position, and the time interval that the terminal device needs to wait after completing channel listening is reduced, thereby reducing resource waste. In the following FIG. 6 The sidelink communication method of the embodiments of the present application is introduced.

[0101] Referring to FIG. 6 In step S610, the terminal device performs channel listening in a shared spectrum.

[0102] The terminal device is a device for sidelink communication. The terminal device can be a device that needs to transmit data in sidelink communication.

[0103] The terminal device can perform unicast communication, groupcast communication or broadcast communication with other terminal devices. In some embodiments, the terminal device performing channel listening can be a group head terminal initiating groupcast or broadcast communication, or can be a group member in the groupcast or broadcast communication. For example, in V2X, the terminal device performing channel listening can be a vehicle performing groupcast communication with other vehicles, or can be other vehicles in the groupcast communication.

[0104] In some embodiments, the terminal device performing channel listening can be located within the range of network coverage, or can be located outside the range of network coverage. The terminal device located within the range of network coverage can perform channel listening in the shared spectrum based on the configuration of the network device.

[0105] Channel listening can refer to listening to a plurality of channel resources in the shared spectrum, or listening to a target channel resource.

[0106] The channel resource can be a resource in the shared spectrum, or a COT resource shared by other terminal devices in the sidelink. For example, in V2X, the terminal device can perform channel listening on the COT sharing provided by nearby vehicles.

[0107] In some embodiments, the channel monitoring can refer to that the terminal device monitors the channel resources by using the LBT mechanism, or can refer to that the terminal device monitors the channel resources by using channel sensing or the like. For example, the terminal device can determine the occupation of the sidelink resource based on the value of the reference signal receiving power (RSRP) of the sidelink DMRS.

[0108] The result of the channel monitoring can be that the monitored channel resources are idle, or can be that the monitored channel resources are occupied. If the result of the channel monitoring is that the channel resources are occupied, the terminal device can continue to perform the channel monitoring until an idle channel is found.

[0109] In step S620, if the result of the channel monitoring is that the channel resources are idle, the terminal device starts to transmit the first sidelink channel at the first time domain position.

[0110] The first time domain position can be the transmission starting point after the terminal device accesses the channel. The terminal device can perform the data transmission of the sidelink at the first time domain position.

[0111] In some embodiments, the first time domain position can be a specified time domain position. The terminal device transmits the first sidelink channel at the specified time domain position, and can not be affected by the configuration of the transmission starting point, and the access is more flexible. For example, the first time domain position can be an odd symbol in a time slot after time point synchronization, or can be an even symbol in a time slot after time point synchronization. For another example, the first time domain position can be any symbol after the completion of the channel monitoring.

[0112] FIG. 7 FIG. 7 shows a schematic diagram of data transmission at a specified position. Referring to FIG. 7, the terminal device performs the channel monitoring in the first 5 symbols of the time slot 710, and the 9th symbol of the time slot 710 is the transmission starting point of the sidelink. FIG. 7 That is, the 4th symbol after the completion of the channel monitoring can be specified as the first time domain position. As shown in FIG. 7, the terminal device can effectively utilize the resources in the time slot 710 to perform the data transmission, and does not need to wait until the time slot 720 to perform the access. FIG. 7

[0113] In some embodiments, the first time domain position can be indicated based on first indication information. The first indication information can be carried in the control signaling. For example, the first indication information can be carried in the scheduling indication information of the SCI.

[0114] In some embodiments, the first time domain position can be a time domain position determined based on a first time unit. The first time unit can be a time unit smaller than a time slot.

[0115] ​As a possible implementation, the first time unit can be half a slot. After the terminal device successfully performs channel listening in the early part of a slot, it can perform sidelink transmission at the half-slot position, which helps reduce resource waste. This channel access method can be referred to as half-slot channel access. For example, when a slot contains 14 symbols, half-slot channel access is based on a synchronization time point, and every 7 symbols serves as a transmission starting point.

[0116] FIG. 8 FIG. 8 shows a schematic diagram of half-slot channel access. As shown in FIG. 8, the half-slot position of slot 820 serves as a transmission starting point. After the terminal device completes channel listening in the last 3 symbols of slot 810 and the first 2 symbols of slot 820, it performs channel access at the half-slot position of slot 820. FIG. 8 FIG. 8 As shown in FIG. 8, after the terminal device completes channel listening in the second symbol of slot 820, it does not need to wait for the next slot before performing data transmission.

[0117] The length of the first time unit in half-slot channel access is related to the subcarrier spacing. For example, when the subcarrier spacing is 30 kHz, the length of a slot is 0.5 ms, and the length of the first time unit is 0.25 ms.

[0118] As a possible implementation, the first time unit can be one or more symbols. The number of symbols can be any integer less than the total number of symbols in a slot. When the number of symbols is less than half a slot, the terminal device waits for a smaller time interval before performing data transmission after successful channel listening. For example, based on a synchronization time point, every 3 symbols serves as a transmission starting point.

[0119] When the first time unit is one or more symbols, the length of the first time unit is related to the number of symbols and the length of each symbol. The length of each symbol is related to the subcarrier spacing. For example, when the subcarrier spacing is 15 kHz, the length of each symbol is 66.7 μs.

[0120] As a possible implementation, the first time unit can be one or more microseconds. When the first time unit is multiple microseconds, the terminal device can perform channel access based on a finer time unit. For example, when multiple terminal devices perform data transmission at the same time domain position, the symbols near the time domain position are divided into multiple contention time slots of microseconds. That is, the first time domain position is set with a granularity of multiple microseconds. Each terminal device can select one contention time slot as a transmission starting point according to a standard or configuration. In principle, when multiple terminal devices want to perform data transmission at the same time domain position, the terminal device that completes channel listening earlier is allowed to occupy the position. Therefore, it can be specified that the terminal device that completes channel listening earlier has priority in selecting the first time domain position.

[0121] ​When the first time unit is multiple microseconds, the problem of resource collisions can be effectively resolved. For ease of understanding, the following example demonstrates how to solve... FIG. 5 Taking the resource collision shown as an example, combined with FIG. 9 A more detailed description of the refined channel access methods is provided.

[0122] See FIG. 9 ,based on FIG. 5 The location where resource collision occurs is the contact point between two time slots, and the two symbols adjacent to the contact point are divided. That is, the last symbol (#13) of time slot 910 and the first symbol (#0) of time slot 920 are divided according to time unit 931.

[0123] In the diagram, starting point 941 is the transmission start point of terminal device 1, and starting point 942 is the transmission start point of terminal device 2. Terminal device 1 and terminal device 2 can... FIG. 5 The additional LBTs shown are synchronized to their respective transmission starting points and begin transmission after CCA.

[0124] If start point 941 and start point 942 appear in the last symbol of time slot 910, the terminal device can start transmission directly. If start point 941 and start point 942 appear in the first symbol of time slot 920, the terminal device can start transmission by shielding... FIG. 9 The AGC symbol shown is used to initiate the transmission.

[0125] Depend on FIG. 9 It is evident that by using more precise time division and more specific microsecond-level channel access, collisions can be avoided to the greatest extent possible. FIG. 9 The multi-microsecond time slot access shown can occur in any system-specified symbol.

[0126] In some embodiments, one or more microseconds can be determined based on a specified time unit. The specified time unit can be specified in the indication information of the control signaling. For example, the contention time slot when multiple terminal devices access the channel can be specified as 20 microseconds via SCI.

[0127] In some embodiments, one or more microseconds may also be determined based on the duration of channel listening. The first time unit needs to meet the access requirements for channel listening. For example, a first time unit of 9 μs can meet the requirements. FIG. 4 The minimum time requirement for the additional LBT is shown. For example, a first time unit of 16 μs can meet the requirement. FIG. 4 The example shows the access method of type 2B. For instance, a first time unit of 25μs can meet the requirements. FIG. 4 The access method shown is type 2A.

[0128] As a possible implementation, the multiple microseconds can be a first value or an integer multiple of the first value. The first value can be a specified time unit or a time unit determined based on the length of channel sensing. For example, the first value can be 9 microseconds, 16 microseconds, or 25 microseconds.

[0129] The first sidelink channel can include one or more of a PSCCH, a PSSCH, and a PSFCH, without limitation.

[0130] As can be seen from the above, the embodiments of the present application increase the number of SL-U transmission starting points on the basis of the full-time slot channel access supported by the current 3rd generation partnership project (3GPP) protocol. The time slot structure of SL-U increases the flexibility of channel access, reduces the probability of resource collision, and reduces resource waste and access delay caused by channel access delay through support for specified position access, half-time slot, and more refined access.

[0131] As described above, in the resource scheduling mode of sidelink mode 2, the terminal device needs to perform resource selection after successful channel sensing. During the duration of sensing and processing transmission preparation by the terminal device, other RATs can access and occupy the channel, causing the previous channel sensing of the terminal device to be invalid.

[0132] Based on this, the embodiments of the present application propose another sidelink communication method and device. In this method, after the terminal device successfully accesses the channel, it can obtain the resources required for subsequent transmission without resource selection. The following describes the sidelink communication method in detail. FIG. 10 The sidelink communication method is described in detail. FIG. 10 The method shown is related to FIG. 6 Therefore, in order to be brief, FIG. 10 The terms already appeared will not be explained in detail. FIG. 6 The terms already appeared will not be explained in detail.

[0133] Referring to FIG. 10 At step S1010, the terminal device performs channel access on a first resource of a shared spectrum.

[0134] The channel access can be the initial access of the terminal device for data transmission. In some embodiments, the channel access can only include the initial access of the terminal device. For example, the channel access can be resource sensing access. In some embodiments, the channel access can include channel sensing and initial access of the terminal device.

[0135] The first resource can be a time-frequency resource designated in the shared spectrum or a reserved time-frequency resource, or a shared resource in a resource pool corresponding to another terminal device in the shared spectrum. The terminal device performs channel access on the first resource, which can also be referred to as an access resource.

[0136] In some embodiments, the shared resource as the first resource can be a resource in a resource pool configured by the network for another terminal device, or a resource in a resource pool obtained by channel listening by another terminal device. For example, the first resource can be a reserved resource in the resource pool of another terminal device.

[0137] In some embodiments, the first resource can be used for resource sensing access by the terminal device. The first resource can be used as a resource required for initial access by the terminal device, or as a resource required for channel listening and initial access by the terminal device. For example, the first resource can determine the channel listening access of the terminal device.

[0138] In some embodiments, the first resource can be used for initial transmission by the terminal device. The terminal device can perform channel listening before the first resource, and if no available channel is found, the terminal device can wait on the first resource.

[0139] In some embodiments, the first resource can also be used for retransmission resources in a dedicated frequency band. For example, the first resource can be used for some retransmissions of a transport block (TB).

[0140] In some embodiments, the information of the first resource can be notified in multiple ways. For example, the first resource can be notified to the terminal device of the sidelink by using dedicated control signaling. For another example, the first resource can be notified to the terminal device of the sidelink by broadcast information.

[0141] In step S1020, the terminal device transmits a first sidelink channel on the second resource.

[0142] The second resource can be a time-frequency resource available to the terminal device through channel listening. The terminal device transmits data on the second resource, which can also be referred to as a transmission resource. For example, the second resource can be an available resource in the shared spectrum, or a shared resource in the resource pool of another terminal device.

[0143] The second resource can be a resource block associated with the first resource in the resource pool. In some embodiments, the second resource can be a continuous resource block, a single resource block, or a discrete resource block.

[0144] In some embodiments, the first resource can be associated with a second resource in the resource pool when the first resource is required for access. For example, the first resource can be an index of the second resource. Through the indication of the first resource index, the second resource in the resource pool can be mapped.

[0145] The second resource can be a resource required for subsequent transmission after the terminal device successfully performs channel listening. For example, when the first resource is an index of the second resource, as long as the terminal device successfully performs channel listening on the first resource, the resource index can point to the resource required for subsequent transmission of the service. The terminal device does not need to perform subsequent resource selection or request resource allocation, and thus can avoid possible resource conflict problems.

[0146] In some embodiments, the association relationship between the first resource and the second resource can also be notified in various ways. For example, the association relationship can be notified to the terminal device of the sidelink by using dedicated control signaling. For another example, the association relationship can be notified to the terminal device of the sidelink by using broadcast information.

[0147] The association relationship between the first resource and the second resource can be determined based on one or more types of information.

[0148] In some embodiments, the association relationship between the first resource and the second resource can be determined based on first information. The first information can be used to indicate the time domain position of the second resource. For example, the first information can include the time domain start position and the time duration of the second resource. For another example, the first information can include the time domain start position and the end time of the second resource.

[0149] As a possible implementation, the first information is represented by ConfigIndex, T initial represents the time domain start position, and L represents the time duration. The first information satisfies:

[0150] ConfigIndex∈[T initial , T initial +L];

[0151] wherein T initial is the start symbol of the time domain of the second resource, and can be determined based on a synchronization time point. L can be the symbol length of the duration of the second resource.

[0152] As a possible implementation, the time domain start position of the second resource can be the time domain start position of the first time unit or the time domain start position indicated by the indication information. The first time unit can be a time slot, can be a half time slot, can be one or more symbols, or can be one or more microseconds, without limitation. For example, when a time slot includes 14 symbols, in the case of a time slot as the first time unit, the time domain position of every 14 symbols based on the synchronization timeline is Tinitial ; the time domain position T initial specified by the indication information is T initial .

[0153] In some embodiments, the first information can be determined based on one or more information when multiple terminal devices wish to transmit sidelink channel in the second resource. The information can be the maximum value of available time domain resources in the resource pool, which can be represented as T max , for example, the maximum number of available symbols, or the maximum number of symbols that can be shared by COT. The information can be the total number of the second resource in the time domain of the resource pool, for example, K, K being a positive integer. The information can also be the number of terminal devices, for example, M terminal devices actually accessing at a certain time, M can be a positive integer less than or equal to K. The information can be the number of the second resource corresponding to each terminal device in the time domain, for example, K / M.

[0154] As a possible implementation, the time domain resources in the resource pool are equally divided. T max After the K time domain resources are equally divided, the L in the foregoing can be represented as L = T max / K, and the first information of each resource block satisfies:

[0155] ConfigIndex ∈ [T initial , T initial +(T max / K)].

[0156] The first information of the i-th resource block satisfies:

[0157]

[0158] wherein i is an integer ranging from 0 to K-1, is the symbol in a time slot in which the service corresponding to the i-th resource block performs channel access after successful channel listening.

[0159] If M terminal devices access the resource pool in which the second resource is located, and the time domain resources are equally divided, the first information ConfigIndex corresponding to the i-th terminal device in the M terminal devices satisfies:

[0160]

[0161] wherein i is an integer ranging from 0 to M-1, denotes the time domain starting position of the second resource corresponding to the i-th terminal device, P denotes the number of the second resource corresponding to the i-th terminal device in the time domain, and T maxP represents the maximum value of available time domain resources in the resource pool, and K represents the total number of the second resources in the time domain of the resource pool. Because the resources are equally divided, P can be defined as K / M.

[0162] As a possible implementation manner, the time domain resources in the resource pool can not be equally divided. For example, the number of symbols of each resource block can be sorted in a differential sequence, or in an increasing sequence or a decreasing sequence.

[0163] In some embodiments, the association relationship between the first resource and the second resource can be determined based on second information. The second information can be used to indicate the frequency domain position of the second resource. For example, the second information can include the frequency domain starting position and the frequency domain size of the second resource. For another example, the second information can include the frequency domain starting position and the frequency domain ending position of the second resource.

[0164] As a possible implementation manner, the second information can be represented by FreqIndex. FreqIndex can indicate the starting physical resource block (PRB) of the second resource in the frequency domain, or can indicate the frequency domain size occupied by the second resource. For example, the RBs occupied by the second resource can be one or more consecutive RBs, or can be multiple non-consecutive RBs. For another example, the multiple RBs occupied by the second resource can be a fixed value, or can be set differently according to the priority level of the terminal device or the transmission service.

[0165] As a possible implementation manner, the RBs in the resource pool are sorted based on the frequency index. For example, the RBs are numbered in the order of increasing frequency starting from the lowest frequency of the resource pool. n_SL_PRB can be the RB number of the starting frequency domain of the second resource in the resource pool, and RB offset may be the number of RBs offset in the frequency domain by the second resource, and therefore the second information satisfies:

[0166] FreqIndex∈[n_SL_PRB,n_SL_PRB+RB offset ];

[0167] Wherein, n_SL_PRB represents the frequency domain starting position, and RB offset represents the frequency domain size.

[0168] In some embodiments, when multiple terminal devices want to transmit sidelink channels in the second resource, the second information can be determined based on one or more information. These information can be the maximum value of available frequency domain resources in the resource pool, which can be represented by N max , for example, the number of the largest available resources in the bandwidth part (bandwidth part, BWP) This information could be the total number of second resources in the frequency domain of the resource pool, for example, K. This information could be the number of terminal devices, for example, M. This information could be the number of second resources corresponding to each terminal device in the frequency domain, for example, K / M.

[0169] One possible implementation is to divide the frequency domain resources in the resource pool into equal parts. max After dividing the frequency domain resources into K equal parts, the RB mentioned earlier... offset It can be represented as RB offset =N max / K, the second information for each resource block satisfies:

[0170] FreqIndex∈[n_SL_PRB, n_SL_PRB+(N max / K)).

[0171] The second information of the i-th resource block satisfies:

[0172] FreqIndex∈[n_SL_PRB i n_SL_PRB i +(N max / K)];

[0173] n_SL_PRB i =n_SL_PRB0+i×(N max / K);

[0174] Where i is an integer ranging from 0 to K-1, n_SL_PRB i This indicates the starting position of the frequency domain of the second resource corresponding to the i-th terminal device.

[0175] If M terminal devices access the resource pool containing the second resource, and the frequency domain resources are equally divided, the second information FreqIndex corresponding to the i-th terminal device among the M terminal devices satisfies:

[0176] FreqIndex∈[n_SL_PRB i n_SL_PRB i +P×(N max / K)];

[0177] n_SL_PRB i =n_SL_PRB0+i×P×(N max / K);

[0178] Where i is an integer ranging from 0 to M-1, n_SL_PRB iP represents the number of the second resource corresponding to the i-th terminal device in the frequency domain, N max represents the maximum value of the available frequency domain resources in the resource pool, K represents the total number of the second resource in the frequency domain of the resource pool. Because of the equal division, P can be defined as K / M.

[0179] As a possible implementation manner, the frequency domain resources in the resource pool can not be equally divided. For example, the number of RBs of each resource block can be sorted in a differential sequence, or in an increasing sequence or a decreasing sequence.

[0180] In some embodiments, the association relationship between the first resource and the second resource can be determined based on the first information and the second information. The first information is used to indicate the time domain position of the second resource, and the second information is used to indicate the frequency domain position of the second resource. According to the index of the first resource, the position of the second resource can be determined to avoid subsequent resource conflicts. For example, the index can be represented as Index(x, y), wherein x represents the time domain parameter of the second resource, and y represents the frequency domain parameter of the second resource.

[0181] As a possible implementation manner, the first resource index of the terminal device for initial access on the shared spectrum can be Index(ConfigIndex, FreqIndex). The ConfigIndex and FreqIndex of the second resource are determined respectively according to the method described above. After the terminal device successfully performs channel listening, the position of the transmission PSCCH / PSSCH / PSFCH can be determined according to the index.

[0182] As a possible implementation manner, after multiple terminal devices perform channel access, the available resources in the resource pool can be divided based on the number of terminal devices, so as to obtain the time-frequency resources (ConfigIndex, FreqIndex) allocated to each terminal device.

[0183] As a possible implementation manner, the time-frequency resources available in the resource pool are equally divided. When the equally divided second resources are of the same size, the sidelink can obtain the maximum channel resources. For example, the time-frequency resources are equally divided into N RBG resource groups, N RBG represents the number of resource block groups (RBGs). N RBG also represents the number of terminal devices that the resource pool can allow to allocate resources.

[0184] As a possible implementation, the available resources in the resource pool are divided into resource blocks of different sizes. Each terminal device can transmit on the second resources of different sizes based on the service requirement. For example, the sizes of each resource block can be sorted in a differential sequence, or sorted in an increasing sequence or a decreasing sequence.

[0185] For ease of understanding, the following takes the resource pool of SL-U as an example, and the mapping relationship of equally divided and unequally divided second resources in the resource pool is described respectively in combination with FIG. 11 and FIG. 12 . FIG. 11 As shown in the figure, it is a schematic diagram of the association between the first resources and the second resources when the second resources are equally divided. FIG. 12 As shown in the figure, it is a schematic diagram of the association between the first resources and the second resources when the second resources are unequally divided.

[0186] Referring to FIG. 11 , in the time and frequency interleaved resource pool, each cell on the abscissa is a time slot, and each cell on the ordinate is a sub-channel. Three terminal devices perform channel access in the resource pool. As shown in the figure, FIG. 11 , in the resource pool, the first resources are used as access resources of different terminal devices, and the sizes of the corresponding three resource blocks are different. The second resources are used as transmission resources of different terminal devices, and the sizes of the corresponding three resource blocks are the same. That is, no matter the size of the terminal device service requirement or the access resource, the terminal device will obtain the same size of transmission resource after successful listening.

[0187] FIG. 11 Various mapping relationships of the first resources and the second resources are described. Among them, the mapping relationship 1110 is the mapping case of full-time slot channel access, the mapping relationship 1120 is the mapping case of half-time slot channel access, and the mapping relationship 1130 is the mapping case of specified position channel access.

[0188] FIG. 12 The main difference from FIG. 11 is that the sizes of the resource blocks corresponding to the three second resources are different. That is, the sizes of the transmission resources obtained by the three terminal devices after successful channel listening are different. As shown in the figure, FIG. 12 , in the mapping relationship 1220, the resource block of the second resource is the largest, and the terminal device with large service requirement can perform channel access on the first resource of the mapping relationship 1220.

[0189] From the above, when the terminal device performs channel access on the first resource of the shared spectrum, the terminal device can obtain the subsequent transmission resource based on the association relationship between the first resource and the second resource. That is, as long as the terminal device successfully performs channel listening, the terminal device can ensure the resource required for subsequent transmission. Therefore, the terminal device does not need to perform resource selection again, and the case that the successfully listened channel is occupied by other RATs in the resource selection time is avoided.

[0190] The method embodiments of the present application are described in detail above. FIGS. 6-12 The device embodiments of the present application are described in detail below. It should be understood that the description of the device embodiments corresponds to the description of the method embodiments, and therefore, the parts not described in detail can be referred to the foregoing method embodiments. FIGS. 13-15 The device embodiments of the present application are described in detail below. It should be understood that the description of the device embodiments corresponds to the description of the method embodiments, and therefore, the parts not described in detail can be referred to the foregoing method embodiments.

[0191] FIG. 13 is a schematic block diagram of a communication device of an embodiment of the present application. The device 1300 can be any one of the terminal devices described above. FIG. 13 The device 1300 shown in the figure includes a listening unit 1310 and a transmission unit 1320.

[0192] The listening unit 1310 can be configured to perform channel listening on a shared spectrum.

[0193] The transmission unit 1320 can be configured to start transmitting a first sidelink channel at a first time domain position if the result of the channel listening is that the channel is idle, wherein the first time domain position is one or more of the following: a time domain position indicated by the first indication information; a time domain position determined based on a first time unit, wherein the first time unit is less than one time slot.

[0194] Optionally, the first time unit includes one or more of the following: half a time slot, one or more symbols, and one or more microseconds.

[0195] Optionally, the one or more microseconds are determined based on one or more of the following information: a specified time unit; a length of the channel listening.

[0196] Optionally, the one or more microseconds are a first value or an integer multiple of the first value, and the first value is one of the following: 9 microseconds, 16 microseconds, and 25 microseconds.

[0197] Optionally, the first indication information is carried in control signaling.

[0198] FIG. 14 is a schematic block diagram of a communication device of another embodiment of the present application. The device 1400 can be any one of the terminal devices described above. FIG. 14 The device 1400 shown in the figure includes an access unit 1410 and a transmission unit 1420.

[0199] The access unit 1410 can be configured to perform channel access on the first resource of the shared spectrum, where the first resource is associated with the second resource in the resource pool.

[0200] The transmission unit 1420 can be configured to transmit the first sidelink channel on the second resource.

[0201] Optionally, the association relationship between the first resource and the second resource is determined based on one or more of the following information: first information indicating a time domain position of the second resource; and second information indicating a frequency domain position of the second resource.

[0202] Optionally, the first information includes one or more of the following information: a time domain starting position of the second resource; a time duration of the second resource; and an ending time of the second resource.

[0203] Optionally, the time domain starting position of the second resource is one of the following: a time domain starting position of a first time unit; a time domain starting position indicated by the indication information; wherein the first time unit is one of the following: a time slot, a half time slot, one or more symbols, and one or more microseconds.

[0204] Optionally, the second information includes one or more of the following information: a frequency domain starting position of the second resource; a frequency domain size of the second resource; and a frequency domain ending position of the second resource.

[0205] Optionally, the first information is determined based on one or more of the following: a maximum value of available time domain resources in the resource pool; a total number of the second resources in the time domain of the resource pool; a number of terminal devices; and a number of the second resources corresponding to each terminal device in the time domain.

[0206] Optionally, the terminal device includes M terminal devices, and the first information ConfigIndex corresponding to the i-th terminal device in the M terminal devices satisfies:

[0207]

[0208] wherein i is an integer valued from 0 to M-1, denotes a time domain starting position of the second resource corresponding to the i-th terminal device, P denotes a number of the second resource corresponding to the i-th terminal device in the time domain, T max denotes a maximum value of available time domain resources in the resource pool, K denotes a total number of the second resources in the time domain of the resource pool.

[0209] Optionally, the second information is determined based on one or more of the following: a total number of the second resources in the frequency domain of the resource pool; a number of terminal devices; a maximum value of available frequency domain resources in the resource pool; and a number of the second resources corresponding to each terminal device in the frequency domain.

[0210] Optionally, the terminal device includes M terminal devices, and the second information FreqIndex corresponding to the i-th terminal device in the M terminal devices satisfies:

[0211] FreqIndex∈[n_SL_PRB i , n_SL_PRB i +P×(N max / K)];

[0212] wherein i is an integer ranging from 0 to M-1, n_SL_PRB i denotes a frequency domain starting position of the second resource corresponding to the i-th terminal device, P denotes a quantity of the second resource corresponding to the i-th terminal device in the frequency domain, N max denotes a maximum value of available frequency domain resources in the resource pool, and K denotes a total quantity of the second resource in the frequency domain of the resource pool.

[0213] FIG. 15 Fig. 1 shows a schematic structural diagram of a communication device according to an embodiment of the present application. FIG. 15 The dashed line in Fig. 1 indicates that the unit or module is optional. The device 1500 can be used to implement the methods described in the above method embodiments. The device 1500 can be a chip or a terminal device.

[0214] The device 1500 can include one or more processors 1510. The processor 1510 can support the device 1500 to implement the methods described in the foregoing method embodiments. The processor 1510 can be a general-purpose processor or a dedicated processor. For example, the processor can be a central processing unit (CPU). Alternatively, the processor can also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs) or other programmable logic devices, discrete gates or transistor logic components, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0215] The device 1500 can further include one or more memories 1520. The memory 1520 stores a program, which can be executed by the processor 1510, so that the processor 1510 performs the methods described in the foregoing method embodiments. The memory 1520 can be independent of the processor 1510 or integrated in the processor 1510.

[0216] The apparatus 1500 can further include a transceiver 1530. The processor 1510 can communicate with other devices or chips through the transceiver 1530. For example, the processor 1510 can perform data transceiving with other devices or chips through the transceiver 1530.

[0217] The embodiments of the present application further provide a computer readable storage medium for storing a program. The computer readable storage medium can be applied to the terminal or network device provided by the embodiments of the present application, and the program causes the computer to execute the method performed by the terminal or network device in the embodiments of the present application.

[0218] The embodiments of the present application further provide a computer program product. The computer program product includes a program. The computer program product can be applied to the terminal or network device provided by the embodiments of the present application, and the program causes the computer to execute the method performed by the terminal or network device in the embodiments of the present application.

[0219] The embodiments of the present application further provide a computer program. The computer program can be applied to the terminal or network device provided by the embodiments of the present application, and the computer program causes the computer to execute the method performed by the terminal or network device in the embodiments of the present application.

[0220] The terms "system" and "network" can be used interchangeably in the present application. In addition, the terms used in the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application. The terms "first", "second", "third", and "fourth" and the like in the specification and claims of the present application and the drawings are used to distinguish different objects, and are not used to describe a particular order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion.

[0221] In the embodiments of the present application, the "indication" mentioned can be direct indication, or indirect indication, or can be an indication of an associated relationship. For example, A indicates B, which can mean that B can be obtained through A, or A indirectly indicates B, for example, A indicates C, and B can be obtained through C, or A and B have an associated relationship.

[0222] In the embodiments of the present application, the term "corresponding" can mean a direct or indirect corresponding relationship between the two, or can mean an associated relationship between the two, or can mean an indication and being indicated, configuration and being configured, etc.

[0223] In the embodiments of the present application, the "predefined" or "preconfigured" can be implemented by pre-storing corresponding codes, tables or other manners available for indicating relevant information in devices (for example, including terminal devices and network devices), and the specific implementation manners are not limited in the present application. For example, the predefinition can refer to definition in a protocol.

[0224] In the embodiments of the present application, the "protocol" can refer to a standard protocol in the communication field, for example, can include the LTE protocol, the NR protocol and relevant protocols applied in future communication systems, and the present application is not limited thereto.

[0225] In the embodiments of the present application, according to A to determine B does not mean that B is determined only according to A, but also can be determined according to A and / or other information.

[0226] In the embodiments of the present application, the term "and / or" is only used to describe the association relationship of the associated objects, and can represent three relationships, for example, A and / or B can represent three cases of A alone, A and B together, and B alone. In addition, the character " / " in the present application generally represents an "or" relationship between the associated objects.

[0227] In various embodiments of the present application, the size of the serial number of the above processes does not mean the order of execution, and the execution order of the processes should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0228] In several embodiments provided by the present application, it should be understood that the disclosed system, device and method can be implemented by other manners. For example, the device embodiments described above are only schematic, for example, the division of the units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, and can be electrical, mechanical or other forms.

[0229] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. According to actual needs, part or all of the units can be selected to achieve the purpose of the embodiments of the present application.

[0230] In addition, each function unit in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit.

[0231] In the above embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center through wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) mode. The computer readable storage medium can be any available medium that can be read by a computer or a data storage device such as a server, data center, etc. integrated with one or more available media. The available media can be magnetic media (for example, floppy disk, hard disk, magnetic tape), optical media (for example, digital video disc (DVD)) or semiconductor media (for example, solid state disk (SSD)) and the like.

[0232] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for side-to-side communication, characterized in that, include: The terminal device accesses the channel on a first resource of the shared spectrum, wherein the first resource is associated with a second resource in the resource pool; The terminal device is in the first side row channel of the second resource transmission; The association between the first resource and the second resource is determined based on first information, which indicates the temporal location of the second resource. The terminal device includes... M A terminal device, the M The first of the terminal devices i The first information ConfigIndex corresponding to each terminal device satisfies: ； in, i The value ranges from 0 to M Integers of -1 Indicates the first i The temporal starting position of the second resource corresponding to each terminal device. P Indicates the first i The number of second resources corresponding to each terminal device in the time domain. This represents the maximum available time-domain resources in the resource pool. K This represents the total quantity of the second resource in the time domain of the resource pool.

2. The method according to claim 1, characterized in that, The association between the first resource and the second resource is also determined based on second information, which is used to indicate the frequency domain location of the second resource.

3. The method according to claim 1 or 2, characterized in that, The first information includes one or more of the following: The temporal starting position of the second resource; The duration of the second resource; and The end time of the second resource.

4. The method according to claim 3, characterized in that, The temporal starting position of the second resource is one of the following: The time-domain start position of the first time unit; The indication information indicates the start position in the time domain; The first time unit can be one of the following: a time slot, a half time slot, one or more symbols, or one or more microseconds.

5. The method according to claim 2, characterized in that, The second information includes one or more of the following: The frequency domain start position of the second resource; The frequency domain size of the second resource; and The end position of the frequency domain of the second resource.

6. The method according to claim 2 or 5, characterized in that, The second information is determined based on one or more of the following: The maximum value of available frequency domain resources in the resource pool; The total number of the second resource in the frequency domain of the resource pool; The number of terminal devices; and The number of second resources in the frequency domain corresponding to each terminal device.

7. The method according to claim 6, characterized in that, The terminal device includes M A terminal device, the M The first of the terminal devices i The second information FreqIndex corresponding to each terminal device satisfies: ； in, i The value ranges from 0 to M Integers of -1 Indicates the first i The frequency domain starting position of the second resource corresponding to each terminal device. P Indicates the first i The number of second resources corresponding to each terminal device in the frequency domain. This represents the maximum available frequency domain resources in the resource pool. K This represents the total quantity of the second resource in the frequency domain of the resource pool.

8. A device for side-to-side communication, characterized in that, The device is a terminal device, and the device includes: An access unit is configured to perform channel access on a first resource of a shared spectrum, wherein the first resource is associated with a second resource in a resource pool; Transmission unit, used to transmit the first side row channel in the second resource; The association between the first resource and the second resource is determined based on first information, which indicates the temporal location of the second resource. The terminal device includes... M A terminal device, the M The first of the terminal devices i The first information ConfigIndex corresponding to each terminal device satisfies: ； in, i The value ranges from 0 to M Integers of -1 Indicates the first i The temporal starting position of the second resource corresponding to each terminal device. P Indicates the first i The number of second resources corresponding to each terminal device in the time domain. This represents the maximum available time-domain resources in the resource pool. K This represents the total quantity of the second resource in the time domain of the resource pool.

9. The apparatus according to claim 8, characterized in that, The association between the first resource and the second resource is also determined based on second information, which is used to indicate the frequency domain location of the second resource.

10. The apparatus according to claim 8 or 9, characterized in that, The first information includes one or more of the following: The temporal starting position of the second resource; The duration of the second resource; and The end time of the second resource.

11. The apparatus according to claim 10, characterized in that, The temporal starting position of the second resource is one of the following: The time-domain start position of the first time unit; The indication information indicates the start position in the time domain; The first time unit can be one of the following: a time slot, a half time slot, one or more symbols, or one or more microseconds.

12. The apparatus according to claim 9, characterized in that, The second information includes one or more of the following: The frequency domain start position of the second resource; The frequency domain size of the second resource; and The end position of the frequency domain of the second resource.

13. The apparatus according to claim 9 or 12, characterized in that, The second information is determined based on one or more of the following: The maximum value of available frequency domain resources in the resource pool; The total number of the second resource in the frequency domain of the resource pool; The number of terminal devices; and The number of second resources in the frequency domain corresponding to each terminal device.

14. The apparatus according to claim 13, characterized in that, The terminal device includes M A terminal device, the M The first of the terminal devices i The second information FreqIndex corresponding to each terminal device satisfies: ； in, i The value ranges from 0 to M Integers of -1 Indicates the first i The frequency domain starting position of the second resource corresponding to each terminal device. P Indicates the first i The number of second resources corresponding to each terminal device in the frequency domain. This represents the maximum available frequency domain resources in the resource pool. K This represents the total quantity of the second resource in the frequency domain of the resource pool.

15. A communication device, characterized in that, It includes a memory and a processor, the memory being used to store a program, and the processor being used to invoke the program in the memory to perform the method as described in any one of claims 1-7.

16. A computer-readable storage medium, characterized in that, It contains a program that causes a computer to perform the method as described in any one of claims 1-7.

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