Communication method and apparatus, and storage medium

Abstract

The present application discloses a communication method and apparatus, and a storage medium. A first terminal receives from a second terminal first information indicating reservation of a first time-frequency resource; the first terminal acquires a first COT, the first COT at least comprising a second time-frequency resource and the first time-frequency resource; the first terminal receives from a third terminal second information indicating reservation of the second time-frequency resource; and when the first terminal determines that the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the first terminal sends to the second terminal third information indicating sharing of the first time-frequency resource to the second terminal. In the present application, when the first terminal triggers resource selection, the priority corresponding to the first terminal and / or the second terminal is compared with the priority corresponding to the third terminal, and when the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the resource can be shared to the second terminal, thereby improving the reliability of unlicensed resource sharing.

Description

Communication method, device and storage medium

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on August 9, 2023, with application number 202311002257.6 and invention name “Communication Method, Device and Storage Medium”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a communication method, device, and storage medium. Background Art

[0003] In unlicensed frequency bands, user equipment (UE) needs to use spectrum resources in a competitive manner. For example, it is possible to compete for channels in a listen-before-talk (LBT) manner. Unlicensed spectrum resources can be shared between different UEs, that is, as long as the network equipment complies with certain regulations, it can use the spectrum to receive and send information. If a UE obtains available time-frequency resources through LBT, the length of time that can continuously send information corresponding to the available time-frequency resources is called the channel occupancy time (COT). After the UE obtains the COT, it can share the resources within the COT with other UEs. After receiving the shared information, other UEs can use the specified resources to send information at the specified time.

[0004] As shown in the existing resource selection diagram in Figure 1, before triggering resource selection, UE3 listens to UE1's reservation information (for example, reserving resources for time slot t3). UE1 can be the receiving end of UE3, or a UE with higher priority. After UE3 obtains COT, it can share some resources with UE1. When UE3 re-evaluates or preempts the evaluation at time m-T3, it finds that the selected resources (resources corresponding to time slots t1 and t2) are selected or preempted by a third UE (for example, UE2). This is because UE2 may not have received UE1's reservation information due to half-duplex or distance issues. If UE3 selects other resources, the initially selected resources (resources corresponding to time slots t1 and t2) will be used by UE2, and UE1's transmission cannot be guaranteed.

[0005] Summary of the Invention

[0006] The present application provides a communication method, device, and storage medium to improve the reliability of unauthorized resource sharing.

[0007] In the first aspect, a communication method is provided, which can be executed by a terminal, or by a module applied to the terminal (such as a processor, chip, or chip system, etc.), or by a logical node, logical module or software that can realize all or part of the terminal functions.

[0008] The method includes: a first terminal receives first information from a second terminal, the first information indicating a reservation for a first time-frequency resource; the first terminal performs channel access to obtain a first COT, the first COT including at least a second time-frequency resource and the first time-frequency resource; the first terminal receives second information from a third terminal, the second information indicating a reservation for the second time-frequency resource; and when the first terminal determines that the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the first terminal sends third information to the second terminal, the third information indicating sharing the first time-frequency resource with the second terminal. In this aspect, when triggering resource selection, the first terminal compares the priority corresponding to itself and / or the second terminal with the priority corresponding to the third terminal. If the priority corresponding to itself and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the first terminal can share the resource with the second terminal, thereby improving the reliability of unauthorized resource sharing.

[0009] In one possible implementation, the method further includes: the first terminal using the second time-frequency resource for communication. In this implementation, when the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the second time-frequency resource is used by the first terminal, thereby allowing the first terminal to use the second time-frequency resource for communication.

[0010] In another possible implementation, the method further includes: the first terminal sending a cyclic prefix extension before using the second time-frequency resource, wherein the starting position or length of the cyclic prefix extension is related to the priority corresponding to the first terminal and / or the second terminal. In this implementation, the first terminal sends the cyclic prefix extension before using the second time-frequency resource to preempt the channel, and the starting position or length of the cyclic prefix extension is related to the priority corresponding to the first terminal and / or the second terminal, which makes it easier for the first terminal to preempt the channel.

[0011] In another possible implementation, when the first terminal determines that the service priority corresponding to the first terminal and / or the second terminal is higher than or equal to the service priority corresponding to the third terminal, the first terminal sends third information to the second terminal.

[0012] In another possible implementation, when the first terminal determines that the channel access priority corresponding to the first terminal and / or the second terminal is higher than or equal to the channel access priority corresponding to the third terminal, the first terminal sends third information to the second terminal.

[0013] In another possible implementation, a starting position or length of the cyclic prefix extension is related to a service priority corresponding to the first terminal and / or the second terminal.

[0014] In another possible implementation, the starting position or length of the cyclic prefix extension is related to the channel access priority corresponding to the first terminal and / or the second terminal.

[0015] In another possible implementation, a higher priority corresponds to an earlier starting position of the cyclic prefix extension, or a longer length of the cyclic prefix extension. In this implementation, a higher priority corresponds to an earlier starting position of the cyclic prefix extension, or a longer length of the cyclic prefix extension, which facilitates the first terminal to seize the channel more easily.

[0016] In yet another possible implementation, the priority is a service priority or a channel access priority.

[0017] In another possible implementation, the first time-frequency resource occupies the available frequency domain resources of the entire channel in the frequency domain. In this implementation, when the first time-frequency resource occupies the available frequency domain resources of the entire channel in the frequency domain, the starting position or length of the cyclic prefix extension can be determined based on the priority corresponding to the first terminal and / or the second terminal.

[0018] In another possible implementation, the first terminal does not detect reservation information of other terminals in the time slot corresponding to the first time-frequency resource. In this implementation, when the first terminal device does not detect reservation information of other terminals in the time domain of the first time-frequency resource, the starting position or length of the cyclic prefix extension can be determined based on the priority corresponding to the first terminal and / or the second terminal.

[0019] In another possible implementation, the second time-frequency resource occupies the available frequency domain resources of the entire channel in the frequency domain. In this implementation, when the second time-frequency resource occupies the available frequency domain resources of the entire channel in the frequency domain, the starting position or length of the cyclic prefix extension can be determined based on the priority corresponding to the first terminal and / or the second terminal.

[0020] In another possible implementation, the first terminal does not hear reservation information of other terminals in the time slot corresponding to the second time-frequency resource. In this implementation, when the first terminal device does not hear reservation information of other terminals in the time domain of the second time-frequency resource, the starting position or length of the cyclic prefix extension can be determined based on the priority corresponding to the first terminal and / or the second terminal.

[0021] In another possible implementation, the second terminal is a receiving terminal of the first terminal. In this implementation, the second terminal is a receiving terminal of the first terminal, so that after the first terminal completes LBT, it can share the remaining resources occupied by itself with the second terminal, thereby improving the reliability of communication between the first terminal and the second terminal.

[0022] In another possible implementation, a first time interval exists between the second time-frequency resource and the first time-frequency resource. In this implementation, when the first terminal determines that the second time-frequency resource can be used, it sends third information indicating that the first time-frequency resource can be shared with the second terminal. The second terminal requires a certain amount of time to parse the third information. Therefore, a certain time interval is required between the second time-frequency resource and the first time-frequency resource.

[0023] In yet another possible implementation, the first time interval is associated with a subcarrier spacing.

[0024] In a possible implementation, the second time-frequency resource precedes the first time-frequency resource in the time domain.

[0025] In another possible implementation, the second time-frequency resource is reserved by the first terminal. In this implementation, the method can be applied to a resource preemption scenario.

[0026] In a second aspect, a communication device is provided for implementing the communication method of the first aspect or any one of the implementations of the first aspect. The device may be a terminal, a module applied to a terminal (e.g., a processor, a chip, or a chip system), or a logical node, a logical module, or software that implements all or part of the terminal's functions.

[0027] In one possible implementation, the device includes: a transceiver unit and a processing unit; wherein: the transceiver unit is used to receive first information from a second terminal, the first information indicating a reservation of a first time-frequency resource; the processing unit is used to perform channel access and obtain a first channel occupancy time COT, the first COT including at least a second time-frequency resource and the first time-frequency resource; the transceiver unit is also used to receive second information from a third terminal, the second information indicating a reservation of the second time-frequency resource; and the transceiver unit is also used to send third information to the second terminal when the processing unit determines that the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the third information indicating sharing the first time-frequency resource with the second terminal.

[0028] Optionally, the transceiver unit is further used to communicate using the second time-frequency resources.

[0029] Optionally, the transceiver unit is further used to send a cyclic prefix extension before using the second time-frequency resource, wherein the starting position or length of the cyclic prefix extension is related to the priority corresponding to the first terminal and / or the second terminal.

[0030] Optionally, the higher the priority, the earlier the starting position of the corresponding cyclic prefix extension, or the longer the length of the corresponding cyclic prefix extension.

[0031] Optionally, the priority is a service priority or a channel access priority.

[0032] Optionally, the first time-frequency resources occupy available frequency domain resources of the entire channel in the frequency domain.

[0033] Optionally, the communication device does not detect reservation information of other terminals in the time domain time slot corresponding to the first time-frequency resource.

[0034] Optionally, the second time-frequency resources occupy available frequency domain resources of the entire channel in the frequency domain.

[0035] Optionally, the communication device does not detect reservation information of other terminals in the time domain time slot corresponding to the second time-frequency resource.

[0036] Optionally, the second terminal is a receiving end of the first terminal.

[0037] Optionally, there is a first time interval between the second time-frequency resource and the first time-frequency resource.

[0038] Optionally, the first time interval is associated with a subcarrier spacing.

[0039] Optionally, the second time-frequency resource is reserved by the first terminal.

[0040] In another possible implementation, the communication device in the second aspect includes a processor coupled to a memory; the processor is configured to enable the device to perform the corresponding functions in the above-mentioned communication method. The memory is coupled to the processor and stores the necessary programs (instructions) and / or data for the device. Optionally, the communication device may further include a communication interface for enabling communication between the device and other network elements. Optionally, the memory may be located inside or outside the communication device.

[0041] In another possible implementation, the communication device in the second aspect includes a processor and a transceiver, the processor being coupled to the transceiver, and the processor being used to execute a computer program or instruction to control the transceiver to receive and send information; when the processor executes the computer program or instruction, the processor is also used to implement the above method through a logic circuit or executing code instructions. The transceiver may be a transceiver, a transceiver circuit, or an input / output interface, configured to receive signals from other communication devices other than the communication device and transmit them to the processor, or to send signals from the processor to other communication devices other than the communication device. When the communication device is a chip, the transceiver is a transceiver circuit or an input / output interface.

[0042] When the communication device in the second aspect is a chip, the sending unit may be an output unit, such as an output circuit or a communication interface; the receiving unit may be an input unit, such as an input circuit or a communication interface. When the communication device is a terminal, the sending unit may be a transmitter or a transmitter; and the receiving unit may be a receiver or a receiver.

[0043] In a third aspect, a computer-readable storage medium is provided, in which a computer program or instruction is stored. When the computer program or instruction is executed, the method described in the first aspect or any one of the implementations of the first aspect is implemented.

[0044] In a fourth aspect, a computer program product comprising instructions is provided. When the instructions are executed on a communication device, the communication device executes the method described in the first aspect or any one of the implementations of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a schematic diagram of existing resource selection;

[0046] FIG2 is a schematic diagram of the architecture of a communication system used in an embodiment of the present application;

[0047] FIG3 is a schematic diagram of C-V2X provided in an embodiment of the present application;

[0048] FIG4 is a schematic diagram of an example of an interleaved resource block according to an embodiment of the present application;

[0049] FIG5 is a schematic diagram of indicating available subframes for SL communication through a bit map in an NR SL according to an embodiment of the present application;

[0050] FIG6 is a schematic diagram of frequency resources of an SL communication resource pool according to an embodiment of the present application;

[0051] FIG7 a is a schematic diagram of sub-channels with interleaved resource blocks as the granularity;

[0052] FIG7 b is a schematic diagram of a sub-channel with continuous RB resources as the granularity;

[0053] FIG8 is a schematic diagram showing the relationship between physical time slots and logical time slots according to an embodiment of the present application;

[0054] FIG9 is a schematic diagram of a sub-channel according to an embodiment of the present application;

[0055] FIG10 is a schematic diagram of a resource selection process according to an embodiment of the present application;

[0056] FIG11 is a schematic diagram of reservation-based COT sharing according to an embodiment of the present application;

[0057] FIG12 is a schematic diagram of an open COT sharing example according to an embodiment of the present application;

[0058] FIG13 is a schematic diagram of a CP duplication process in an OFDM symbol according to an embodiment of the present application;

[0059] FIG14 is a schematic diagram of a CPE process in an NR-U system according to an embodiment of the present application;

[0060] FIG15 a is a schematic diagram showing the distribution of the starting positions of CPEs at 30 kHz according to an embodiment of the present application;

[0061] FIG15 b is a schematic diagram showing the distribution of the starting positions of CPEs at 60 kHz according to an embodiment of the present application;

[0062] FIG16 is a schematic diagram of an application scenario in which different priorities determine different CPE lengths according to an embodiment of the present application;

[0063] FIG17 is a schematic diagram of a COT sharing solution provided in an embodiment of the present application;

[0064] FIG18 is a schematic diagram of another COT sharing solution provided in an embodiment of the present application;

[0065] FIG19 is a schematic diagram of another COT sharing solution provided in an embodiment of the present application;

[0066] FIG20 is a flow chart of a communication method provided in an embodiment of the present application;

[0067] FIG21 is a schematic diagram of a network scenario in which a terminal according to an example embodiment of the present application is located;

[0068] FIG22 is a schematic diagram of a COT sharing solution in a resource reassessment scenario provided by an embodiment of the present application;

[0069] FIG23 is a schematic diagram of a COT sharing solution in a resource preemption evaluation scenario provided by an embodiment of the present application;

[0070] FIG24 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0071] Figure 25 is a structural diagram of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0072] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.

[0073] The following at least one (item) involved in this application indicates one (item) or more (items). More than one (item) refers to two (items) or more than two (items). "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. In addition, it should be understood that although the terms first, second, etc. may be used to describe each object in this application, these objects should not be limited to these terms. These terms are only used to distinguish each object from each other.

[0074] The terms "including" and "having" and any variations thereof mentioned in the following description of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include other steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices. It should be noted that, in this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any method or design described in this application as "exemplary" or "for example" should not be interpreted as being more preferred or more advantageous than other methods or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete way.

[0075] The technology provided by this application can be applied to various communication systems. For example, the communication system can be a fourth generation (4G) th generation, 4G) communication systems (such as long term evolution (LTE) systems), fifth generation (5 th The 5G communication system may also be referred to as a new radio (NR) system.

[0076] A network element in a communication system can send a signal to another network element or receive a signal from another network element. The signal may include information, signaling, or data, etc. The network element can also be replaced by an entity, a network entity, a device, a terminal device, a communication module, a node, a communication node, etc. The present application uses the network element as an example for description. For example, the communication system may include at least one terminal device and at least one access network device. The access network device can send a downlink signal to the terminal device, and / or the terminal device can send an uplink signal to the access network device. In addition, it can be understood that if the communication system includes multiple terminal devices, the multiple terminal devices can also send signals to each other, that is, the signal sending network element and the signal receiving network element can both be terminal devices.

[0077] The communication method provided in the embodiments of the present application can be applied to wireless communication systems such as 5G, 6G, and satellite communications. Figure 2 is a schematic diagram of the architecture of the communication system used in the embodiments of the present application. As shown in Figure 2, the communication system 1000 includes a radio access network 100 and a core network 200. Optionally, the communication system 1000 may also include the Internet 300. The radio access network 100 may include at least one radio access network device (such as 110a and 110b in Figure 2) and may also include at least one terminal (such as 120a-120j in Figure 2). The terminal is connected to the radio access network device via wireless, and the radio access network device is connected to the core network via wireless or wired. The core network device and the radio access network device can be independent and different physical devices, or the functions of the core network device and the logical functions of the radio access network device can be integrated into the same physical device, or the functions of some core network devices and some radio access network devices can be integrated into one physical device. Terminals and radio access network devices can be connected to each other via wired or wireless means. FIG2 is only a schematic diagram. The communication system may further include other network devices, such as wireless relay devices and wireless backhaul devices, which are not shown in FIG2 .

[0078] The wireless access network device can be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next-generation base station (next generation NodeB, gNB) in the fifth generation (5G) mobile communication system, a next-generation base station in the sixth generation (6G) mobile communication system, a base station in a future mobile communication system, or an access node in a WiFi system, etc.; it can also be a module or unit that completes part of the functions of a base station, for example, it can be a centralized unit (CU) or a distributed unit (DU). The wireless access network device can be a macro base station (such as 110a in Figure 2), a micro base station or an indoor station (such as 110b in Figure 2), or a relay node or a donor node, etc. The embodiments of the present application do not limit the specific technology and specific device form adopted by the wireless access network device. For the sake of convenience, the following description takes the base station as an example of the wireless access network device.

[0079] The terminal may also be referred to as a terminal device, user equipment (UE), mobile station, mobile terminal, etc. The terminal can be widely used in various scenarios, for example, device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, etc. The terminal can be a mobile phone, tablet computer, computer with wireless transceiver function, wearable device, vehicle, drone, helicopter, airplane, ship, robot, robotic arm, smart home device, road side unit (RSU), vehicle-mounted module, vehicle-mounted module, chip or whole vehicle, etc. The embodiments of the present application do not limit the specific technology and specific device form adopted by the terminal.

[0080] Base stations and terminals can be fixed or mobile. They can be deployed on land, indoors or outdoors, handheld or vehicle-mounted; on water; or in the air on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of base stations and terminals.

[0081] The roles of base stations and terminals can be relative. For example, the helicopter or drone 120i in Figure 2 can be configured as a mobile base station. To terminals 120j accessing the wireless access network 100 via 120i, terminal 120i is a base station. However, to base station 110a, 120i is a terminal, meaning that communication between 110a and 120i occurs via a wireless air interface protocol. Of course, communication between 110a and 120i can also occur via a base station-to-base station interface protocol. In this case, 120i is also a base station relative to 110a. Therefore, base stations and terminals can be collectively referred to as communication devices. 110a and 110b in Figure 2 can be referred to as communication devices with base station functionality, while 120a-120j in Figure 2 can be referred to as communication devices with terminal functionality.

[0082] Communication between base stations and terminals, between base stations, and between terminals can be carried out through authorized spectrum, unauthorized spectrum, or both; communication can be carried out through spectrum below 6 gigahertz (GHz), spectrum above 6 GHz, or spectrum below 6 GHz and spectrum above 6 GHz. The embodiments of the present application do not limit the spectrum resources used for wireless communication.

[0083] In the embodiments of the present application, the functions of the base station may also be performed by a module (such as a chip) in the base station, or by a control subsystem that includes the base station functions. The control subsystem that includes the base station functions here may be a control center in the above-mentioned application scenarios such as smart grid, industrial control, smart transportation, and smart city. The functions of the terminal may also be performed by a module (such as a chip or modem) in the terminal, or by a device that includes the terminal functions.

[0084] In this application, a base station sends downlink signals or downlink information to a terminal, and the downlink information is carried on a downlink channel. The terminal sends uplink signals or uplink information to the base station, and the uplink information is carried on an uplink channel. To communicate with the base station, the terminal establishes a wireless connection with the cell controlled by the base station. The cell with which the terminal has established a wireless connection is called the terminal's serving cell. When the terminal communicates with the serving cell, it will also be subject to interference from signals in neighboring cells.

[0085] In the embodiments of the present application, the time domain symbols may be orthogonal frequency division multiplexing (OFDM) symbols or discrete Fourier transform-spread-OFDM (DFT-s-OFDM) symbols. Unless otherwise specified, the symbols in the embodiments of the present application refer to time domain symbols.

[0086] It can be understood that in the embodiments of the present application, the physical downlink shared channel (PDSCH), the physical downlink control channel (PDCCH) and the physical uplink shared channel (PUSCH) are only used as examples of downlink data channels, downlink control channels and uplink data channels, respectively. In different systems and different scenarios, data channels and control channels may have different names, and the embodiments of the present application do not limit this.

[0087] Cellular vehicle-to-everything (C-V2X):

[0088] C-V2X is a V2X communication technology developed based on cellular systems. It utilizes and enhances current cellular network functions and elements to achieve low-latency and high-reliability communication between various nodes in the vehicle network. As shown in Figure 3, a schematic diagram of C-V2X provided in an embodiment of the present application is provided, which includes vehicle-to-vehicle communication (vehicle to vehicle, V2V), vehicle-to-pedestrian communication (vehicle to pedestrian, V2P), vehicle-to-infrastructure communication (vehicle to infrastructure, V2I), and vehicle-to-network communication (vehicle to network, V2N). With the evolution of cellular systems from LTE to 5G, C-V2X has also evolved from LTE-V2X to new radio V2X (NR-V2X).

[0089] V2X communication has enormous potential to reduce vehicle collisions and, consequently, the number of casualties. The advantages of V2X extend beyond safety. Vehicles capable of V2X communication contribute to better traffic management, further promoting green transportation and lowering energy consumption. Intelligent transportation systems (ITS) are an application that integrates V2X. Based on V2X technology, vehicle users (V-UEs) can transmit information such as their location, speed, and intentions (turns, lane changes, and reversing)—periodic information, as well as non-periodic event-triggered information—to surrounding V-UEs. Similarly, V-UEs receive real-time information from surrounding users. 5G NR V2X supports lower transmission latency, more reliable communication, higher throughput, and a better user experience, meeting the needs of a wider range of application scenarios. Furthermore, the vehicle-to-vehicle communication technology supported by V2X can be extended to device-to-device (D2D) communication in any system.

[0090] Wireless communication systems are categorized into licensed and unlicensed frequency bands based on the frequency bands used. In licensed frequency bands, users utilize spectrum resources based on scheduling by a central node. In LTE systems, cellular mobile communications have begun researching unlicensed frequency bands, leading to the development of technologies such as LTE in unlicensed spectrum (LTE-U), licensed assisted access (LAA), and MulteFire. However, unlicensed frequency bands were already used by some wireless communication devices, such as Wi-Fi. The LTE system introduced a listen-before-talk (LBT) mechanism to enable coexistence with Wi-Fi devices and enable LTE Uu interface communication in unlicensed frequency bands. In addition to the Uu interface, there is also a PC5 interface, which is a communication interface between UEs. The transmission link in the PC5 interface is defined as the sidelink (SL). Enabling SL communication in unlicensed frequency bands within a local area is a key evolutionary direction, and the corresponding protocol technologies are collectively referred to as SL-U. Similar to the Uu interface, UEs using the SL-U protocol also need to coexist with nearby Wi-Fi devices based on the LBT mechanism.

[0091] In unlicensed frequency bands, transmitting nodes need to use spectrum resources in a competitive manner. Specifically, they compete for channels through the listen-before-talk (LBT) method. The LBT mechanism is essentially a channel access rule based on random back-off. Before accessing the channel and starting to send data, the UE needs to sense whether the channel is idle. If the channel has been idle for a certain period of time, it can occupy the channel. If the channel is not idle, it needs to wait for the channel to become idle again before it can occupy the channel. The reason why the LBT mechanism has become a mandatory feature of unlicensed frequency bands is that various regions of the world have regulations for the use of unlicensed frequency bands. UEs of various forms working with different communication protocols can only use unlicensed frequency bands if they meet the regulations, thereby using spectrum resources relatively fairly and efficiently.

[0092] Unlicensed spectrum resources can be shared between different user devices. This means that any network device that complies with certain regulations can use this spectrum to transmit and receive information. If a user device obtains a transmission opportunity through LBT, the corresponding length of time during which information can be continuously transmitted is called the channel occupancy time (COT). After obtaining the COT, the user device can share the spectrum with other user devices and send the shared resources within the COT, including the corresponding time and frequency domain location, to these other user devices. Upon receiving this shared information, other user devices can use the specified frequency domain resources to transmit information at the specified time.

[0093] In addition, the devices used in D2D technology are generally half-duplex devices, that is, the UE can only be in the state of receiving or sending information at the same time and does not have the ability to send and receive simultaneously.

[0094] The PC5 interface has two resource allocation modes: Mode 1 and Mode 2. In Mode 1, the base station allocates transmission resources to V2X via the Uu interface, so UEs operating in Mode 1 must be within network coverage. SL spectrum resources can be shared with uplink communication resources. In SL communications, Mode 1 and Mode 2 can be allocated to different resource pools or share a resource pool. Resource pool sharing can improve resource utilization efficiency, but it can also easily lead to conflicts between Mode 1 and Mode 2. Therefore, Mode 1 UEs will notify Mode 2 UEs of their allocated resources for future transmissions.

[0095] NR-U adopts LBT channel access method. The LBT access method generally adopts energy-based detection and signal type detection. For example, NR-U adopts energy detection, while WiFi adopts a combination of the two detection methods. Energy-based detection requires setting an energy detection threshold. When the detected energy exceeds the detection threshold, it is judged that the channel is busy and access to the channel is not allowed. When the detected energy is lower than the detection threshold, if it continues for more than a period of time, access to the channel is allowed. According to national and regional regulations on the use of unlicensed frequency bands, taking the 5GHz band as an example, accessing a 20MHz channel requires meeting at least the minimum occupied channel bandwidth (OCB) requirement before the channel can be occupied. Generally, the minimum OCB must be at least 80% of the normal bandwidth. Taking 20MHz as an example, at least 16MHz of bandwidth must be occupied to seize the 20MHz channel. 3rd Generation Partnership Project (3 rd The 3GPP NR-U system introduces the concept of interlaced resource blocks, defining interlacem∈{0,1,…,M-1} to include multiple {m,M+m,2M+m,3M+m,…} resource blocks (RBs). When the subcarrier spacing (SCS) is 15KHz, M=10, and when the subcarrier spacing is 30KHz, M=5. As shown in Figure 4, a schematic diagram of an interlaced resource block in an embodiment of the present application is shown. For a 15kHz SCS, interlace#1 has 10 interlaced resource blocks, each of which is the 10th RB of a subchannel.

[0096] The time and frequency resources of SL communication are configured based on the SL communication resource pool. The SL communication resource pool can be regarded as a collection of time resources and frequency resources used for SL communication. For time resources, the base station uses a bit map and periodically repeats the bit map to indicate the set of subframes used for SL communication in all subframes in the system. As shown in Figure 5, it is a schematic diagram of indicating the available subframes for SL communication through a bit map in the NR SL of the embodiment of the present application, and the length of the bit map is 8 bits. The number of symbols occupied by SL transmission in each subframe is a fixed M symbols, and M is defined as the duration of an SL time domain transmission, or a time domain transmission unit.

[0097] For the frequency resources of the SL communication resource pool, the base station divides the frequency band used for SL communication into several sub-channels. Resource selection and transmission are determined based on the sub-channel granularity, and each sub-channel contains a certain number of resource blocks. As shown in Figure 6, it is a schematic diagram of the frequency resources of the SL communication resource pool of the embodiment of the present application, in which the base station indicates the sequence number of the first resource block of the frequency resources used for SL communication, the total number of sub-channels N contained in the communication resource pool, and the number of resource blocks n contained in each sub-channel. CH SL transmission can occupy one or more sub-channels at a time. When scheduling SL communication resources, scheduling is performed in the frequency domain at the granularity of sub-channels.

[0098] In the embodiment of the present application, a subchannel can be defined as consisting of one or more interlaces, as shown in Figure 7a, which illustrates a subchannel with interleaved resource blocks as the granularity. An interlace can span multiple resource block sets (RB sets) or only one RB set, with one RB set corresponding to a 20MHz channel. Alternatively, a subchannel can be composed of multiple consecutive RB resources, as shown in Figure 7b, which illustrates a subchannel with consecutive RB resources as the granularity.

[0099] In the present application, occupying all frequency domain resources may mean occupying all available frequency domain resources of a channel.

[0100] To meet regulatory requirements, LBT mechanisms are generally divided into the following four categories:

[0101] Category 1 LBT: Transmits immediately after a short switching gap. This is referred to as Category 1 LBT and is used when a communication device switches from a receive state to a transmit state during the COT (Counting Time Interval). The COT refers to the time a communication device is allowed to occupy a channel after successfully accessing it. The switching gap cannot exceed 16µs.

[0102] Category 2 LBT: LBT without random backoff. Also known as Category 2 LBT, it allows a communication device to transmit without random backoff after detecting that the channel is idle for a specified period of time.

[0103] Category 3 LBT: LBT with random backoff and a fixed-size contention window. Also known as Category 3 LBT, it involves a communication device generating a random number N based on a fixed-size contention window and transmitting only after detecting that the channel is idle for a period of time determined by the random number N. The size of the contention window is related to the minimum and maximum values ​​of N.

[0104] Category 4 LBT: LBT with random backoff and a variable-sized contention window. Also known as Category 4 LBT, this protocol allows a communication device to generate a random number, N, based on a variable-sized contention window and transmit only after detecting that the channel is idle for a period of time determined by the random number, N. The size of the contention window is dependent on the minimum and maximum values ​​of N, and the communication device can adjust the size of the contention window.

[0105] NR-U devices follow the 3GPP protocol and use the LBT mechanism as the channel access method. Specifically, NR-U devices use the following types of LBT:

[0106] Type 1 LBT: Category 4 LBT. NR-U devices must perform a random backoff before accessing the channel and sending data.

[0107] Specifically, the network device or the terminal device can delay sensing for an extended period of time (denoted as T d After the sensing channel is idle for a sensing slot duration of 100 ms and after the counter N in the following step 4 is zero, information transmission can be initiated. Specifically, the counter N is adjusted by sensing the channel to obtain an additional sensing slot duration according to the following steps:

[0108] 1) Set N = N init , where N init is evenly distributed between 0 and CW p Random number between, go to step 4;

[0109] 2) If N>0, the network device or terminal device chooses to decrement the counter, then set N=N-1;

[0110] 3) According to T sl = 9us time granularity to listen to the channel. If the channel is idle at the listening time granularity, go to step 4; otherwise, go to step 5;

[0111] 4) If N=0, stop; otherwise, go to step 2.

[0112] 5) Continue listening to the channel until another T d A T inside sl The channel is busy or another T d All listening time slots T sl All are detected as idle channels;

[0113] 6) If in another T d Listening time slot T sl If both channels are detected as idle, go to step 4; otherwise, go to step 5;

[0114] T d Including duration T f = 16us and followed by m p consecutive listening time slots (denoted as T sl ), CW min,p ≤CW p ≤CW max,p For the competition window.

[0115] Select CW before step 1 of the above procedure min,p and The CW max,p . Where m p 、CW min,p and The CW max,p It is based on the channel access priority level p associated with the network device or terminal device transmission, as shown in Table 1 below:

[0116] Table 1

[0117] The COT of the network equipment or terminal transmitted on the channel does not exceed T mcot,p , where the channel access procedure is performed based on a channel access priority level p associated with the network device or terminal transmission.

[0118] Network devices or terminals maintain contention window value CW p , and adjust CW according to the following steps before step 1 in the above fallback p The value of:

[0119] For each priority class p∈{1,2,3,4}, set CW p =CW min,p .

[0120] If at least Z = 80% of the feedback HARQ-ACK values ​​corresponding to the data sent by the network device or terminal in the reference subframe k are determined to be NACK, the CW corresponding to each priority class p∈{1,2,3,4} is set to pThe value increases to the next higher allowed value and continues to make ACK / NACK judgment in step 2. Otherwise, execute step 1 and set CW p =CW min,p The reference subframe k is the starting subframe of the most recent transmission of the network device or terminal on the channel.

[0121] Type 2A LBT: Category 2 LBT with a 25µs interval. An NR-U device can access the channel and send data after detecting that the channel is idle for 25µs.

[0122] Type 2B LBT: Cat 2 LBT with a 16-µs interval. An NR-U device can access the channel and send data after detecting that the channel is idle for 16 µs.

[0123] Type 2C LBT: Category 1 LBT with a maximum interval of 16µs. NR-U devices do not need to listen to the channel and can directly access the channel and send data after a transition interval of up to 16µs within the COT.

[0124] From the perspective of the device type that performs LBT, when the NR-U device and WiFi coexist, it can act as a load-based equipment (LBE), which can perform channel perception and contend for access at any time point without considering frame boundaries. In addition to supporting work as an LBE, it also supports work as a frame-based equipment (FBE). At this time, the NR-U device is only allowed to obtain COT through competitive access to the channel on the frame boundary synchronized within the system. The "frame" here means a fixed frame period (FFP). The specific period value is configured by radio resource control (RRC) signaling. The current protocol supports period values ​​of 1ms, 2ms, 2.5ms, 4ms, 5ms and 10ms, which can all be divided by 2 radio frame durations, that is, 20ms.

[0125] Mode2 resource exclusion selection process:

[0126] Under network coverage, the terminal can obtain SL resource pool configuration information and / or SL bandwidth part (BWP) configuration information by receiving the system information block (SIB) of the network device, cell-level (cell-specific) RRC signaling or user-level (UE-specific) RRC signaling. The terminal can also use pre-configured SL resource pool configuration information or SL BWP configuration information, for example, when there is no network coverage. The SL resource pool configuration information includes resource pool resource information, and the resource pool resource information is used to indicate the SL resource pool. The resource pool is a collection of time-frequency resources used for sideline communication between UEs. The resource pool may include code domain resources. The resources of the resource pool are used by the terminal to send and receive resources of at least one of the following physical channels: physical sidelink control channel (PSCCH) (used to carry sidelink control information (SCI)), physical sidelink shared channel (PSSCH) (used to carry at least one of control information, data, sidelink CSI feedback information, etc.), physical sidelink discovery channel (PSDCH) (used to carry discovery messages), physical sidelink feedback channel (PSFCH) (used for sidelink feedback information, sidelink feedback information can be used for data information (including hybrid automatic repeat request (HARQ) response feedback information, such as acknowledgement (ACK) or negative acknowledgement (NACK), and may also include channel state indication (CSI)). The PSSCH may also be used to indicate at least one of the following information: energy-saving information, resource assistance information (including recommended resources, non-recommended resources, resource collisions, resource reservation conflicts, past or future half-duplex conflicts), a physical sidelink broadcast channel (PSBCH) (used to carry information related to sidelink synchronization), etc. The service types carried by the PSSCH may include unicast, multicast, and / or broadcast communication types.In the time domain, the SL resource pool includes one or more time units. A time unit can be one or more symbols, one or more slots, one or more mini-slots, one or more subframes, or one or more frames. One or more time units can be continuous or discrete in time. It should be understood that within a resource pool, the time domain units are logically continuous.

[0127] As shown in Figure 8, it is a schematic diagram of the relationship between the physical time slots and the logical time slots of the embodiment of the present application. Time slots 1 to 8 are time slots that are continuous in time, and such time slots are called physical slots. The physical time slots - time slot 1, time slot 3, time slot 5 and time slot 8 are configured as time slots belonging to a resource pool. Because the time slots contained in the resource pool may be discontinuous in time, from the perspective of the resource pool, time slot 1, time slot 3, time slot 5 and time slot 8 on the physical time slot correspond to time slot 1', time slot 2', time slot 3' and time slot 4' in the resource pool. Then. The continuous time slots contained in the resource pool (i.e., time slot 1', time slot 2', time slot 3' and time slot 4') are time slots that are continuous logically from the perspective of the resource pool. Such logically continuous but not necessarily temporally continuous time slots are called logical slots. In the frequency domain, the SL resource pool includes one or more frequency domain units, which can be a resource element (RE), several REs, a resource block (RB), several RBs, a subchannel, or several subchannels. The subchannel size, which indicates the number of continuous or interlaced RBs in the frequency domain, can be an integer such as 10, 12, 15, 20, 25, or 50.

[0128] The SL resource pool configuration information may also include PSCCH configuration information, which includes the number of symbols occupied by the PSCCH in a timeslot and the number of resource blocks occupied by the PSCCH in a subchannel. The SL BWP configuration information may include SL resource pool information, which is used to configure the number of resource pools included in the BWP. The SL BWP configuration information may also include SL bandwidth information, which is used to indicate the bandwidth size for SL communication, for example, indicating that the SL bandwidth is 20 megahertz (MHz).

[0129] The SL BWP configuration information may also include SL symbol information, which is used to indicate the starting SL symbol position on a time slot and the number of continuous SL symbols occupied. The SL BWP configuration information may also include SL subcarrier spacing and cyclic prefix information, which are used to indicate the subcarrier spacing and cyclic prefix used for SL communication. The cyclic prefix indicates an extended cyclic prefix or a normal cyclic prefix. In one possible configuration, the SL BWP configuration information may also include SL resource pool configuration information. In the embodiments of the present application, unless the meaning of the time unit is specifically stated, it is described in terms of time slots, but the time unit is not limited to time slots; unless the meaning of the time-frequency domain unit is specifically stated, it is described in terms of subchannels, but the frequency domain unit is not limited to subchannels.

[0130] The SCI of the NR SL system is divided into first-level SCI and second-level SCI. PSCCH carries the first-level SCI, which is used to schedule the second-level SCI and PSSCH. Since SL is a distributed system, all UEs need to correctly decode the first-level SCI before decoding the second-level SCI and PSSCH. However, in order to reduce the complexity of the UE's blind decoding of PSCCH, the resource location of PSCCH is relatively fixed, and the format information of the first-level SCI carried is also relatively unique. That is, the UE does not need to blindly detect the time-frequency resource location where the PSCCH is located, nor does it need to blindly detect SCI of different formats. The UE only needs to detect whether there is a first-level SCI at the fixed PSCCH time-frequency resource location. PSCCH may exist in each subchannel on each time slot, that is, the time domain starting position of a PSCCH is the second symbol used for SL transmission on each time slot, the length is 2 or 3 symbols (determined by the resource pool configuration information), the frequency domain position is the minimum PRB index of each subchannel, and the length is at least 10 PRBs (determined by the resource pool configuration information) but not exceeding the size of the subchannel, as shown in Figure 9, a schematic diagram of the subchannel of an example embodiment of the present application.

[0131] The frequency domain resource assignment field and the time domain resource assignment field in the first-level SCI are used to indicate the frequency domain resources and time domain resources for transmitting PSSCH, respectively. The resource reservation period field is used to indicate the resources for periodically reserving the transmission of PSSCH. The value of the resource reservation period field is configured by the network device, or preconfigured, or predefined. For example, the first RRC signaling indicates that the first RRC signaling can determine the sidelink-resource reservation period (sl-ResourceReservePeriod) 1. The format of the second-level SCI is determined by the second-level sidelink control information format (2 nd -stage SCI format) field indicates that the second-stage SCI format field is shown in Table 2 below.

[0132] Table 2

[0133] In V2X SL, the transmission resources of the transmitting UE in user-selected resource mode (Mode 2) are independent of the base station. The transmitting UE selects transmission resources within the resource selection window for communication based on the results of its own perception window. Assuming that the transmitting UE triggers resource selection in time slot n, the resource selection process provided in this embodiment is shown in Figure 10.

[0134] The specific process is described as follows:

[0135] Step 1: UE1 triggers resource selection in time slot n and determines the size of the resource selection window. Specifically, it determines the size of the resource selection window with a time slot and L subCH The candidate resource R is a unit of continuous sub-channels. x,y , resource selection window [n+T1,n+T2], where Determined from the table below, μ SL For the configured subcarrier spacing, the choice of T1 is implementation-based. 2min (high-level configuration) is less than the remaining PDB (data packet delay), then T 2min ≤T2≤PDB (data packet delay), where T2 is chosen based on the implementation; otherwise, T2 is equal to a smaller than PDB.

[0136] Step 2: UE1 determines the size of the resource listening window. Specifically, it determines the perception window T0 is configured by high-level parameters. It can be determined from Table 3 or Table 4 below.

[0137] Table 3

[0138] Table 4

[0139] Step 3: UE1 determines the RSRP threshold of the corresponding reserved resource based on the SCI of the different UE reservation information received. For example, UE1 receives the reservation information of UE2 in the resource window, and determines that the reservation priority indicated in the SCI is prio RX =1, determine the priority of the resource to be selected to send data prio TX =2, then the RSRP threshold corresponding to resource R2 exclusion is determined to be the 9th value in the set. Specifically, the reference signal received power (RSRP) threshold Th (p i ,p j ), RSRP threshold and the prio of the data to be sent TX , and the priority indicated by the received SCI prio RX Regarding Th(p i ,p j ) is specifically the prio in the RSRP threshold value set configured for the resource pool RX +(prio TX -1)*8 threshold values.

[0140] Step 4: Initialize the resource set SA for resource exclusion. The resources in the set include all time-frequency resources in the resource window.

[0141] Step 5: Delete all frequency domain resources in the time slots that are sent in the listening window from the determined initial set. Because it is a half-duplex device, it cannot listen when sending and cannot receive SCI sent by other UEs. For example, if it sends at time t0 in the listening window with a period of p, then the corresponding time slot resources t0+i*p that fall in the resource selection window need to be excluded. Specifically, from S A The following time-frequency resources are excluded: the time slots of all periodic resource reservations configured in the resource pool corresponding to the unperceived time slots (transmitted time slots) in the perception window.

[0142] After the elimination is completed, if it is found that the resources in the resource selection window are insufficient, the resources of the excluded non-listened time slots are put back. Specifically, step 5a:

[0143] If S A If the excluded time-frequency resources are less than X% of the total resources in the resource selection window, re-execute the initialization of step 4 and skip step 5.

[0144] Step 6: Start excluding resources reserved by others, including the following conditions: the reserved SCI is received, the resource indicated by the SCI is in the resource selection window, and the RSRP value of the SCI of the reserved resource is greater than the RSRP threshold value. A The following time-frequency resources are excluded: the decoding of the received first-level SCI is successful, and the RSRP measurement result of the PSSCH demodulation reference signal (DMRS) of the time-frequency resource reserved by the received first-level SCI is higher than the RSRP threshold determined in step 3, and the time-frequency resource reserved by the received first-level SCI is within the resource selection window, including the retransmission resources and periodically reserved resources indicated by the first-level SCI.

[0145] The time-frequency resources reserved by the received first-level SCI (including reservations for multiple consecutive periods and reservations for time resource indication value (TRIV) and frequency resource indication value (FRIV)) are within the resource selection window (where TRIV and FRIV are used to indicate the location of resources for specifying data retransmission).

[0146] Step 7: If UE1 excludes all resources reserved by other UEs, such as those reserved by UE2 and UE3, and finds that the available resources are less than X%, the RSRP threshold for each excluded resource is increased by 3dB, and the exclusion is performed again. Specifically, if S A The remaining resources in the resource selection window are less than X% of the total resources. The value of X% is configured by the resource pool and is consistent with the prio TX If the RSRP threshold determined in step 3 is increased (by 3dB each time), the S A The remaining resources in the resource selection window are not less than X% of the total resources and continue to step 4.

[0147] S A Report to the upper layer (MAC layer).

[0148] In S A Randomly select time-frequency resources (r0, r1, r2, ...) for sending data, and re-evaluate the resources (r0, r1, r2, ...) before sending. After re-evaluation, select the time-frequency resources (r0, r1, r2, ...) from S A The selected resources (r′0, r′1, r′2, …) are preempted.

[0149] The user is in at least time slot Resource re-evaluation and preemption detection are performed at all times. The UE can perform resource re-evaluation and / or preemption detection based on additional triggering before and after the time slot m-T3.

[0150] Since the SCI received from time n to time m-T3 is not used for resource exclusion in the above resource selection process, further confirmation is required to ensure that the selected resources will not be reserved by other UEs, namely re-evaluation and preemption evaluation.

[0151] The method for determining whether (r0, r1, r2, ...) and (r′0, r′1, r′2, ...) need to be excluded is the same as steps 1-7, and one of the following conditions is met: 1) The sl-PreemptionEnable parameter is provided and configured to be enabled, and prio TX >prio RX ; 2) Provide the sl-PreemptionEnable parameter and do not configure it to enable, and meet the prio RX <prio pre and prio TX >prio pre , where prio pre Configured by the higher layer. If r in (r0, r1, r2, ...) and (r′0, r′1, r′2, ...) i and / or r′ i Not S A (ie r i and r′ i are excluded during re-evaluation and / or preemption detection, respectively), then i and / or r′ i Reselect. Wherein, time slot m is the next time slot to be transmitted, that is, time slot m belongs to (r0, r1, r2, ...) and (r'0, r'1, r'2, ...).

[0152] Among them, for the resource preemption part, it is taken into account that the available resources are determined when the resource selection is triggered, but before the resource is used, other UEs may not hear the SCI information of their reserved resources, so other UEs may also select the resources. Therefore, it is necessary to compare the priority of the resources selected by themselves for data transmission with the priority reserved by other UEs to determine whether it is necessary to reselect resources.

[0153] Resource re-evaluation is because when resource selection is triggered, you may have only selected the resource but did not send SCI to make a reservation. At this time, re-evaluation is required before actually using the selected resource to determine whether the resource has been reserved by other UEs. If it is found that the selected resource is no longer in the available resource set when steps 1-7 are re-executed, resource reselection is triggered.

[0154] The priority in this application may be a channel access priority class (CAPC) or a service priority.

[0155] Taking the sidelink information as sidelink data as an example, the priority of the sidelink information may refer to the priority of the PSSCH used to carry the sidelink information, or may also refer to the service priority of the sidelink information.

[0156] For example, the priority levels of the side information may include 1, 2, 3, ..., and 8. A lower priority level indicates a higher priority level for the side information. For example, the priority level 1 for the side information is higher than the priority level 2 for the side information. The priority level 2 for the side information is higher than the priority level 3 for the side information, and so on.

[0157] COT Sharing and CPE:

[0158] After the current terminal completes LBT, it can obtain a continuous channel occupation time. The corresponding frequency domain resource is an RB set. The frequency domain width of a single RB set is 20 MHz. The terminal can also share the resources in the COT with other terminals. There are two solutions for sharing resources:

[0159] 1. COT Sharing Based on Reservation Resources

[0160] This implementation is relatively simple, that is, when a terminal sends data, it can reserve the resources that need to be used subsequently through SCI. Then, the terminal that completes LBT and grabs the COT can determine whether other terminals in its COT have reserved resources based on the SCI of the received reserved resources, and share the resources in the COT with the terminals that have reserved resources.

[0161] For example, as shown in Figure 11, which is a schematic diagram of reservation-based COT sharing in an embodiment of the present application, UE1 completes LBT on time slot n-1 and the time slot before n-1, obtains COT, and before obtaining COT, hears that UE2 has reserved resources for time slot n+2, time slot n+3 and time slot n+4, and UE3 has reserved resources for time slot n+5. UE1 can notify UE2 and UE3 by sending a COT sharing indication message that they can use the resources in their respective reservation locations.

[0162] 2. Open COT Sharing

[0163] In addition to the above methods, regardless of whether resources are reserved, the terminal can share resources with other terminals. However, it may be necessary to indicate the specific time-frequency resource location shared with a specific terminal to avoid transmission conflicts when different terminals use the same shared resources.

[0164] For example, as shown in Figure 12, which is a schematic diagram of open COT sharing as an example of an embodiment of the present application, after UE1 obtains a COT, after using part of the resources in the COT, it can share the remaining resources with other UEs, that is, UE1 uses the resources from time slot n to time slot n+3, and shares the resources of time slot n+4 and time slot n+5 with UE2 and UE3.

[0165] Regardless of the COT sharing method, it involves the need to instruct specific UEs to use the shared COT. Correspondingly, in reservation-based COT sharing, it is necessary to indicate which UEs can use the reserved resources, and it may be necessary to indicate the specific time-frequency resource locations; in the open sharing scenario, it is necessary to specifically indicate which UEs need to use which time-frequency resources.

[0166] Specific notification information can be carried on COT sharing indication information. The indication information can be carried by the first-order SCI, the second-order SCI, or the MAC CE (media access control element). However, considering the decoding delay and the number of available bits, the second-order SCI is more suitable. The following analysis is based on the way the second-order SCI carries the COT sharing indication information.

[0167] In order to indicate which UEs need to use the shared resources, it is necessary to add an additional identifier (Additional ID) in the COT sharing indication information, and send an authorization (Grant) message to the UE with the Additional ID so that the UE can use the shared COT resources.

[0168] The second-order SCI has a total of 140 bits. The bits that must be used are shown in Table 5 below, totaling 45 bits. The remaining maximum 95 bits can be used to carry COT sharing indication information.

[0169] Table 5

[0170] Cyclic prefix extension (CPE):

[0171] After completing LBT, multiple UEs mainly occupy the channel by sending CPE, that is, the cyclic prefix (CP) at the front of the OFDM symbol is further extended to the previous symbol until the LBT end time point. As shown in Figure 13, it is a schematic diagram of the CP copying process in the OFDM symbol of the embodiment of the present application. The tail section of the OFDM data signal will be copied as the CP and its front part will be added. The CP and the OFDM data signal together constitute the OFDM symbol. As shown in Figure 14, it is a schematic diagram of the CPE process in the NR-U system of the embodiment of the present application. Since the LBT end time point of the NR-U device is not the starting point of an OFDM symbol, a complete OFDM symbol cannot be sent. However, according to the LBT mechanism, the NR-U device needs to access the channel immediately, so a part of the subsequent OFDM symbol is further filled into the previous incomplete symbol as the extended CP, and then access and occupy the channel. Based on CPE, the NR-U system can ensure symbol-level synchronization.

[0172] In SL-U, multiple positions are determined for the length of CPE, which can also be called the starting position of CPE. As shown in Figure 15a, it is a distribution diagram of the starting position of CPE at 30KHz in an embodiment of the present application. Taking the subcarrier spacing of 30KHz as an example, there are 7 starting positions, and the length of CPE occupies at most two symbol lengths. For example, for the position of Index#0, the length of CPE is the distance from Index#0 to Index#7, which occupies 55.4us (one symbol length 500 / 14=35.7us). For the subcarrier spacing of 15KHz, there are also 7 starting positions of CPE, and the distribution is consistent with 30KHz, but within one symbol, because the symbol length of 15KHz is twice that of 30KHz. As shown in Figure 15b, it is a distribution diagram of the starting position of CPE at 60KHz in an embodiment of the present application. For 60KHz, there are 3 starting positions of CPE, because the length of CPE can only occupy at most two symbols.

[0173] In unlicensed bands, LBT channel access is required before using resources. However, resource usage in SL is based on time slots. This can lead to resource conflicts if different UEs complete LBT before the same time slot and use resources simultaneously. To address this issue and ensure high-priority data transmission, different UEs can determine the length or starting position of the CPE based on their own priorities. By determining the difference in CPE length for UEs with different priorities, other UEs can avoid using the same resources.

[0174] For example, as shown in Figure 16, which is a schematic diagram of an application scenario in which different CPE lengths are determined for different priorities in an embodiment of the present application, UE1 and UE2 both want to use the resources of time slot n+1. UE1 and UE2 both determine the length of the CPE based on the priority of the data to be transmitted. UE1 has a higher priority and a longer determined CPE length, that is, the corresponding CPE sends the start position earlier, thereby blocking UE2's channel access and ensuring UE1's high-priority data transmission.

[0175] It should be noted that there is a correspondence between the CPE length and the CPE starting position. The earlier the starting position, the longer the corresponding CPE length. At the same time, there is a correspondence between the CPE starting position and the priority. The specific correspondence can be configured or pre-configured.

[0176] This application focuses on the following solution when a UE in SL-U determines that the selected resources can be shared with other UEs with higher priority after determining that the selected resources can be shared with other UEs with higher priority. When performing resource re-evaluation and resource preemption evaluation, an embodiment of this application provides:

[0177] As shown in Figure 17, a schematic diagram of a COT sharing solution provided in an embodiment of the present application is provided. When a UE (such as UE3) selects a resource, it has been considered that the selected resource can be shared with other UEs of higher priority (such as UE1 that has reserved the shared resource) for transmission. However, during the re-evaluation or preemptive evaluation at this time, it is found that the selected resource has been selected by a third UE (such as UE2) or preempted (UE2 has reserved this resource). This is because UE2 may not receive the information about the resource reserved by UE1 due to half-duplex or distance problems. If UE3 uses the resource, it will not share the resource with UE1, or if UE3 selects other resources, the initially selected resource will be used by UE2, and UE1's high-priority transmission cannot be guaranteed.

[0178] It can be seen from this that sidelink technology can be directly multiplexed into SL-U. However, there is no corresponding enhancement to COT sharing during re-evaluation and preemption evaluation to protect the COT sharing mechanism and ensure high-priority transmission.

[0179] During resource re-evaluation, if the UE detects that other UEs have reserved the resources of its choice, it chooses to abandon the resources and reselect. Similar to the above problem, for example, as shown in Figure 18, which is a schematic diagram of another COT sharing solution provided in an embodiment of the present application, UE1 (priority (P) = 1) reserves high-priority resources (resources of the t3 time slot), and UE3 (P = 3) selects the resources of the previous time slot (resources of the t1 and t2 time slots) and prepares to share the resources of the t3 time slot with UE1. However, during the re-evaluation at time m-T3, the reservation of UE2 (P = 2) is detected. At this time, since the priority corresponding to UE3 is lower than the priority corresponding to UE2, UE3 directly abandons the resources it has selected and reselects the resources. UE1's transmission may not be guaranteed.

[0180] For the resource preemption evaluation scenario, when there is COT sharing, this embodiment only considers the priority of the current reservation during preemption evaluation. However, if only the own priority comparison is considered, the COT of the shared UE cannot be guaranteed.

[0181] For example, as shown in Figure 19, which is a schematic diagram of another COT sharing solution provided by an embodiment of the present application, UE3 (P=3) selects resources in time slots t1 and t2 according to the resource exclusion mechanism in this solution when triggering resource selection. However, UE2 (P=2) does not receive the SCI information of UE3's resource reservation due to half-duplex, distance, or other reasons, and also selects resources in time slots t1 and t2. At the same time, if UE2 is unaware that UE3 needs to share resources with UE1 due to distance or other reasons, UE1's high-priority transmission cannot be guaranteed.

[0182] In view of this, an embodiment of the present application also provides a communication solution. When the first terminal triggers resource selection, it compares the priority corresponding to itself and / or the second terminal and the priority corresponding to the third terminal. When the priority corresponding to itself and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the resource can be shared with the second terminal, thereby improving the reliability of unauthorized resource sharing.

[0183] As shown in Figure 20, a flow chart of a communication method provided in an embodiment of the present application is shown. This embodiment is exemplified by the interaction between the first terminal, the second terminal and the third terminal. As shown in Figure 21, a schematic diagram of the network scenario in which the terminal of the example embodiment of the present application is located, the first terminal, the second terminal and the third terminal can work in the scenario with network coverage shown in the first to third figures as shown in Figure 21 (in order from left to right and from top to bottom), or can work in the scenario without network coverage as shown in the fourth figure as shown in Figure 21. In the first figure, each terminal is in network coverage; in the second figure, one of the terminals is in network coverage; in the third figure, each terminal is in different network coverage. Exemplarily, the method may include the following steps:

[0184] S2001. A second terminal sends first information to a first terminal. Correspondingly, the first terminal receives the first information.

[0185] In this embodiment, before the second terminal needs to use the first time-frequency resource, it may first send reservation information, that is, the second terminal sends first information, where the first information indicates the reservation of the first time-frequency resource.

[0186] Exemplarily, the second terminal may be a receiving end of the first terminal, and the second terminal sends the first information to the first terminal.

[0187] Exemplarily, the second terminal may also broadcast the first information. The first terminal may receive the first information broadcast by the second terminal.

[0188] S2002: The first terminal performs channel access and obtains a first COT, which includes at least the second time-frequency resource and the first time-frequency resource.

[0189] The time-frequency resources in this embodiment are unlicensed resources. For the concept of time-frequency resources, please refer to the above description. The first terminal selects time-frequency resources from the resource pool in mode 2.

[0190] As mentioned above, for unlicensed resources, it is necessary to perform channel access and seize the channel before the channel can be used. Therefore, in this embodiment, the first terminal performs channel access and obtains the first COT. The first COT includes at least the second time-frequency resource and the first time-frequency resource. The first terminal obtains the first time-frequency resource and the second time-frequency resource, and can use part of the resources (such as the second time-frequency resource) by itself, and the remaining resources (such as the first time-frequency resource) can be shared with other associated terminals (for example, the receiving end of the first terminal - the second terminal).

[0191] It is worth noting that the first COT here refers to the time-frequency resource set. The time domain is the maximum channel occupancy time corresponding to CAPC, and the frequency domain is the frequency domain resource with a granularity of 20MHz.

[0192] S2003: The third terminal sends second information to the first terminal. Correspondingly, the first terminal receives the second information.

[0193] The second information indicates a reservation for the second time-frequency resource. For example, the third terminal is unaware that the first terminal also intends to use the second time-frequency resource, or that the second time-frequency resource was reserved by the first terminal. Due to half-duplex operation, distance, or other reasons, the third terminal does not receive the reservation information from the first terminal and is unaware that the first terminal has also reserved the second time-frequency resource. The first terminal receives the reservation information (i.e., the second information) from the third terminal.

[0194] Illustratively, the execution order of step S2003 and steps S2001 and S2002 is not limited.

[0195] S2004: When the first terminal determines that the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the first terminal sends third information to the second terminal. Correspondingly, the second terminal receives the third information.

[0196] After the first terminal receives the reservation information (i.e., the first information) from the second terminal and the reservation information (i.e., the second information) from the third terminal, the first terminal compares the priority corresponding to the first terminal with the priority corresponding to the third terminal, and / or compares the priority corresponding to the second terminal with the priority corresponding to the third terminal. When the first terminal determines that the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, it determines that it can continue to use the second time-frequency resources and can share the remaining first time-frequency resources with the second terminal. Therefore, the first terminal sends third information to the second terminal, wherein the third information indicates sharing the first time-frequency resources with the second terminal.

[0197] Exemplarily, the above-mentioned priority may be a service priority or a channel access priority. That is, when the first terminal determines that the service priority corresponding to the first terminal and / or the second terminal is higher than or equal to the service priority corresponding to the third terminal, the first terminal sends the third information to the second terminal; or, when the first terminal determines that the channel access priority corresponding to the first terminal and / or the second terminal is higher than or equal to the channel access priority corresponding to the third terminal, the first terminal sends the third information to the second terminal.

[0198] Compared to the solutions shown in Figures 17-19, the first terminal only compares the priority corresponding to the first terminal with the priority corresponding to the third terminal. When the priority corresponding to the first terminal is lower than the priority corresponding to the third terminal, the first terminal re-allocates resources, which cannot reliably achieve COT sharing and cannot guarantee the transmission of high-priority services of the second terminal. This embodiment compares the priority corresponding to itself and / or the second terminal with the priority corresponding to the third terminal. When the priority corresponding to itself and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, resources can be shared with the second terminal, thereby improving the reliability of unauthorized resource sharing.

[0199] Exemplarily, the third information may be the COT sharing indication information described above. Since the second terminal needs a certain amount of time to parse the third information upon receiving it before using the first time-frequency resource shared by the first terminal, in this embodiment, the first terminal sends the third information on the first time-frequency resource, and a first time interval exists between the second time-frequency resource and the first time-frequency resource.

[0200] Furthermore, the method further comprises the following steps (represented by dotted lines in the figure):

[0201] S2005. The first terminal sends a cyclic prefix extension before using the second time-frequency resource.

[0202] If the first terminal determines that the priority corresponding to the first terminal and / or the second terminal is greater than or equal to the priority corresponding to the third terminal, indicating that the first terminal has already performed channel access, the first terminal sends a CPE message to further reliably seize the channel. The CPE message sent by the first terminal can be received within a certain distance range from the first terminal. In this embodiment, the third terminal can receive the CPE message, causing its corresponding channel access process to fail, and thus being unable to use the first time-frequency resource.

[0203] The meaning of CPE can be found in the previous description. In this embodiment, the starting position or length of the CPE is related to the priority of the first terminal and / or the second terminal. Furthermore, a higher priority corresponds to an earlier starting position of the corresponding CPE; alternatively, a higher priority corresponds to a longer length of the corresponding CPE, thereby enabling the first terminal to more reliably occupy the first COT.

[0204] In one example, the starting position or length of the CPE is related to the service priority corresponding to the first terminal and / or the second terminal. Furthermore, the higher the service priority, the earlier the starting position of the corresponding CPE; or, the higher the service priority, the longer the length of the corresponding CPE.

[0205] In another example, the starting position or length of the CPE is related to the channel access priority corresponding to the first terminal and / or the second terminal. Furthermore, the higher the channel access priority, the earlier the starting position of the corresponding CPE; or, the higher the channel access priority, the longer the length of the corresponding CPE.

[0206] It is understandable that the first terminal can compare the service priority corresponding to the first terminal with the service priority corresponding to the third terminal, and / or compare the service priority corresponding to the second terminal with the service priority corresponding to the third terminal, and when it is determined that the service priority corresponding to the first terminal and / or the second terminal is higher than or equal to the service priority corresponding to the third terminal, the first terminal sends the third information to the second terminal. And the starting position or length of the CPE is determined based on the service priority corresponding to the first terminal and / or the second terminal; or,

[0207] The first terminal may also compare the service priority corresponding to the first terminal with the service priority corresponding to the third terminal, and / or compare the service priority corresponding to the second terminal with the service priority corresponding to the third terminal. If it is determined that the service priority corresponding to the first terminal and / or the second terminal is higher than or equal to the service priority corresponding to the third terminal, the first terminal sends third information to the second terminal. Furthermore, the starting position or length of the CPE is determined based on the channel access priority corresponding to the first terminal and / or the second terminal.

[0208] In addition, the premise for determining the starting position or length of the CPE based on priority is to occupy all channel resources. Therefore, in this embodiment, the first time-frequency resource occupies the available frequency domain resources of the entire channel in the frequency domain, or there are no other terminal reservation resources in the time slot corresponding to the first time-frequency resource, or the first terminal does not hear the reservation information of other terminals in the time slot corresponding to the first time-frequency resource.

[0209] Furthermore, the second time-frequency resource occupies the available frequency domain resources of the entire channel in the frequency domain, or no other terminal has reserved resources in the time slot corresponding to the second time-frequency resource, or the first terminal has not heard the reservation information of other terminals in the time slot corresponding to the second time-frequency resource.

[0210] S2006. The first terminal uses the second time-frequency resource for communication.

[0211] After the first terminal determines that the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, and after the first terminal sends the CPE, the first terminal can use the second time-frequency resources to communicate with other terminals (such as the second terminal in this article) or the network.

[0212] The following is an exemplary description of the solution of this embodiment in the resource re-evaluation and resource preemption evaluation scenarios:

[0213] Figure 22 is a schematic diagram of a COT sharing solution for a resource reassessment scenario provided in an embodiment of the present application. In Figure 22, UE1 and UE4 are terminals associated with UE3. For example, UE1 and UE4 are receiving terminals of UE3. This embodiment uses UE1 and UE4 as the second terminals described above. In this application, the second terminal associated with the first terminal can be one or more terminals.

[0214] In the listening window, UE3 detects that UE1 has reserved resources for time slot t3, and UE4 has reserved resources for time slot t4. UE1's priority is P = 1, UE3's priority is P = 3, and UE4's priority is P = 4. In this embodiment, the smaller P is, the higher the priority.

[0215] UE1 is the data receiving end of UE3. After UE3 seizes the channel, it can share resources with UE1.

[0216] UE3 triggers resource selection at time slot n, determines that the resources of time slots t1 and t2 are available, and selects the resources of time slots t1 and t2. The resources selected by UE3 are at least the two resources before the reserved resources (resources of time slots t3 and t4). This is because if UE3 can share the COT, it needs to send COT sharing indication information to UE1 and UE4. UE1 and UE4 need at least one time slot to decode the COT sharing indication information. Therefore, the first resource selected by UE3 (the resource of time slot t1) and the first shared resource (the resource of time slot t3) cannot be closely adjacent, and a certain time interval is required. This time interval is related to the terminal device decoding the COT sharing indication information.

[0217] When UE2 (priority P=2) selects resources, it may not receive the reservation information of UE1 and / or UE4 due to half-duplex problem, distance problem or other problems. Therefore, UE2 also selects the resource of time slot t1.

[0218] When UE3 performs resource re-evaluation at time m-T3, it detects that UE2 has reserved resources for time slot t1. In this embodiment, UE3 can compare the priority level of UE3, the priority level of UE1 (and the priority level of UE4, if any), and the priority level of UE2. If the priority level of UE3 and / or the priority level of UE1 is higher than or equal to the priority level of UE2 (in Figure 22, the priority level of UE1 is higher than the priority level of UE2), UE3 does not need to trigger resource reselection.

[0219] Then, after UE3 completes LBT in time slot t1, it determines the starting position and / or length of CPE according to the priority corresponding to UE3 and / or the priority corresponding to UE1, and sends CPE.

[0220] Then UE3 can use time slots t1 and t2 for communication. When UE1 uses t1 resources, it can send COT sharing indication information to UE1 and UE4 respectively, indicating that the resources of time slot t3 are shared with UE1 and the resources of time slot t4 are shared with UE4.

[0221] It can be seen that for resource reassessment scenarios, by introducing a priority comparison method to determine whether to reselect resources, and determining the starting position and / or length of the CPE based on priority, the reliability of COT sharing is improved, and high-priority services can be transmitted first.

[0222] Figure 23 is a schematic diagram of a COT sharing solution for a resource preemption evaluation scenario provided in an embodiment of the present application. In Figure 23, UE1 and UE4 are terminals associated with UE3. For example, UE1 and UE4 are receiving terminals of UE3. This embodiment uses UE1 and UE4 as the second terminals described above. In this application, the second terminal associated with the first terminal can be one or more terminals.

[0223] In the listening window, UE3 detects that UE1 has reserved resources for time slot t3, and UE4 has reserved resources for time slot t4. UE1's priority is P = 1, UE3's priority is P = 3, and UE4's priority is P = 4. In this embodiment, the smaller P is, the higher the priority.

[0224] UE1 is the data receiving end of UE3. After UE3 seizes the channel, it can share resources with UE1.

[0225] UE3 sends SCI in time slot t0 and reserves resources for time slot t1. It can also reserve resources for time slot t2.

[0226] UE3 triggers resource selection at time slot n, determines that the resources of time slots t1 and t2 are available, and selects the resources of time slots t1 and t2. The resources selected by UE3 are at least the two resources before the reserved resources (the resources of time slots t3 and t4). This is because, if UE3 can share the COT, it needs to send COT sharing indication information to UE1 and UE4. UE1 and UE4 need at least one time slot to decode the COT sharing indication information. Therefore, the first resource selected by UE3 (the resource of time slot t1) and the first shared resource (the resource of time slot t3) cannot be closely adjacent, and a certain time interval is required.

[0227] When UE2 (priority P=2) selects resources, it may not receive the reservation information of UE1, UE3 and / or UE4 due to half-duplex problem, distance problem or other problems. Therefore, UE2 also selects the resource of time slot t1.

[0228] When UE3 performs resource re-evaluation at time m-T3, it detects that UE2 has reserved resources for time slot t1. In this embodiment, UE3 can compare the priority level of UE3, the priority level of UE1 (and the priority level of UE4, if any), and the priority level of UE2. If the priority level of UE3 and / or UE1 is higher than or equal to the priority level of UE2 (in Figure 23, the priority level of UE1 is higher than the priority level of UE2), UE3 does not need to trigger resource reselection.

[0229] Then, after UE3 completes LBT in time slot t1, it determines the starting position and / or length of CPE according to the priority corresponding to UE3 and / or the priority corresponding to UE1, and sends CPE.

[0230] The priority may be the highest priority among the priorities of multiple UEs (including the UE of the initial COT and multiple UEs of the shared COT). In terms of the priority level, the higher the priority value, the lower the corresponding priority.

[0231] Then UE3 can use time slots t1 and t2 for communication. When UE1 uses t1 resources, it can send COT sharing indication information to UE1 and UE4 respectively, indicating that the resources of time slot t3 are shared with UE1 and the resources of time slot t4 are shared with UE4.

[0232] It can be seen that for resource preemption evaluation scenarios, by introducing a priority comparison method to determine whether to reselect resources and determining the starting position and / or length of the CPE based on priority, the reliability of COT sharing is improved, and high-priority services can be transmitted first.

[0233] According to a communication method provided in an embodiment of the present application, when triggering resource selection, the first terminal compares the priority corresponding to itself and / or the second terminal and the priority corresponding to the third terminal. When the priority corresponding to itself and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the resource can be shared with the second terminal, thereby improving the reliability of unauthorized resource sharing.

[0234] It is understood that, to implement the functions described in the above embodiments, each of the network elements includes hardware structures and / or software modules that perform the corresponding functions. Those skilled in the art will readily appreciate that, in conjunction with the various exemplary units and method steps described in the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is implemented in hardware or in a hardware-driven manner by computer software depends on the specific application scenario and design constraints of the technical solution.

[0235] Figures 24 and 25 are schematic diagrams of possible communication devices provided in embodiments of the present application. These communication devices can be used to implement the functions of the first terminal in the above-described method embodiments, thereby also achieving the beneficial effects of the above-described method embodiments. In the embodiments of the present application, the communication device can be one of the terminals 120a-120j shown in Figure 2, or a module (such as a chip) applied to the terminal.

[0236] As shown in Figure 24, a communication device 2400 includes a processing unit 2410 and a transceiver unit 2420. The communication device 2400 is used to implement the functions of the first terminal in the method embodiment shown in Figure 20 above.

[0237] Among them, the processing unit 2410 is used to execute step S2002 in the method embodiment shown in Figure 20, and can also be used to execute steps S2005 and S2006 in the method embodiment shown in Figure 20; the transceiver unit 2420 is used to execute the functions of the first terminal in steps S2001, S2003 and S2004 in the method embodiment shown in Figure 20.

[0238] A more detailed description of the above-mentioned processing unit 2410 and the transceiver unit 2420 can be directly obtained by referring to the relevant description in the method embodiment shown in Figure 20, and will not be repeated here.

[0239] As shown in Figure 25, communication device 2500 includes a processor 2510 and an interface circuit 2520. Processor 2510 and interface circuit 2520 are coupled to each other. It is understood that interface circuit 2520 can be a transceiver or an input / output interface. Optionally, communication device 2500 may also include a memory 2530 for storing instructions executed by processor 2510, input data required by processor 2510 to execute instructions, or data generated after processor 2510 executes instructions.

[0240] When the communication device 2500 is used to implement the method shown in Figure 20, the processor 2510 is used to implement the functions of the above-mentioned processing unit 2410, and the interface circuit 2520 is used to implement the functions of the above-mentioned transceiver unit 2420.

[0241] When the communication device is a chip implemented in a first terminal, the chip in the first terminal implements the functions of the first terminal in the above-described method embodiment. The chip in the first terminal receives information from other modules (such as a radio frequency module or antenna) in the first terminal, where the information is sent from a second terminal or a third terminal to the first terminal; or the chip in the first terminal sends information to other modules (such as a radio frequency module or antenna) in the first terminal, where the information is sent from the first terminal to a second terminal or a third terminal.

[0242] It is understood that the processor in the embodiments of the present application may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0243] The method steps in the embodiments of the present application can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in a random access memory, a flash memory, a read-only memory, a programmable read-only memory, an erasable programmable read-only memory, an electrically erasable programmable read-only memory, a register, a hard disk, a mobile hard disk, a compact disc read-only memory (CD-ROM) or any other form of storage medium well known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a network device or a terminal. Of course, the processor and the storage medium can also be present in a network device or a terminal as discrete components.

[0244] In the above embodiments, all or part of the embodiments may be implemented using software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer programs or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are performed in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user device, or other programmable device. The computer program or instructions may be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions may be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium may be any available medium accessible by a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; an optical medium, such as a digital video disk; or a semiconductor medium, such as a solid-state drive.

[0245] In the various embodiments of the present application, unless otherwise specified or there is a logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0246] In the present application, "at least one" means one or more, and "more" means two or more. "At least one of the following: ..." or similar expressions means any one of the listed items or any combination of these items. For example, "at least one of the following: A, B and C", or "at least one of the following: A, B or C", can all mean: A exists alone, B exists alone, C exists alone, A and B exist at the same time, B and C exist at the same time, A and C exist at the same time, and A, B and C exist at the same time, where A, B, and C can be singular or plural. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. In the text description of the present application, the character " / " generally indicates that the previous and next associated objects are in an "or" relationship; in the formula of the present application, the character " / " indicates that the previous and next associated objects are in a "division" relationship.

[0247] It is understood that the various numbers used in the embodiments of this application are merely for ease of description and are not intended to limit the scope of the embodiments of this application. The order of the sequence numbers of the above-mentioned processes does not necessarily imply a specific order of execution; the order of execution of the processes should be determined by their functions and inherent logic.

Claims

1. A communication method, characterized in that: The method comprises: The first terminal receives first information from the second terminal, where the first information indicates a reservation of a first time-frequency resource; The first terminal performs channel access and obtains a first channel occupation time COT, where the first COT includes at least the first time-frequency resource and the second time-frequency resource; The first terminal receives second information from a third terminal, where the second information indicates reserving the second time-frequency resource; When the first terminal determines that the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, the first terminal sends third information to the second terminal, and the third information indicates sharing the first time-frequency resources with the second terminal.

2. The method according to claim 1, characterized in that The method further comprises: The first terminal uses the second time-frequency resources for communication.

3. The method according to claim 2, characterized in that The method further comprises: The first terminal sends a cyclic prefix extension before using the second time-frequency resource, wherein a starting position or a length of the cyclic prefix extension is related to a priority corresponding to the first terminal and / or the second terminal.

4. The method according to claim 3, characterized in that The higher the priority, the earlier the starting position of the corresponding cyclic prefix extension, or the longer the length of the corresponding cyclic prefix extension.

5. The method according to any one of claims 1 to 4, characterized in that The priority is a service priority or a channel access priority.

6. The method according to any one of claims 1 to 5, characterized in that The first time-frequency resource occupies available frequency domain resources of the entire channel in the frequency domain, or the first terminal does not detect reservation information of other terminals in the time slot corresponding to the first time-frequency resource.

7. The method according to any one of claims 1 to 6, characterized in that The second terminal is a receiving end of the first terminal.

8. The method according to any one of claims 1 to 7, characterized in that There is a first time interval between the second time-frequency resource and the first time-frequency resource.

9. The method according to any one of claims 1 to 8, characterized in that The second time-frequency resource is reserved by the first terminal.

10. A communication device, characterized in that: The device comprises: a transceiver unit and a processing unit; wherein: The transceiver unit is configured to receive first information from a second terminal, where the first information indicates a reservation of a first time-frequency resource; The processing unit is configured to perform channel access and obtain a first channel occupation time COT, where the first COT at least includes a second time-frequency resource and the first time-frequency resource; The transceiver unit is further configured to receive second information from a third terminal, where the second information indicates a reservation of the second time-frequency resource; The transceiver unit is also used to send third information to the second terminal when the processing unit determines that the priority corresponding to the first terminal and / or the second terminal is higher than or equal to the priority corresponding to the third terminal, and the third information indicates sharing the first time-frequency resource with the second terminal.

11. The device according to claim 10, characterized in that The transceiver unit is further used to communicate using the second time-frequency resources.

12. The device according to claim 11, characterized in that The transceiver unit is further used to send a cyclic prefix extension before using the second time-frequency resource, wherein the starting position or length of the cyclic prefix extension is related to the priority corresponding to the first terminal and / or the second terminal.

13. The device according to claim 12, characterized in that The higher the priority, the earlier the starting position of the corresponding cyclic prefix extension, or the longer the length of the corresponding cyclic prefix extension.

14. The device according to any one of claims 10 to 13, characterized in that The priority is a service priority or a channel access priority.

15. The device according to any one of claims 10 to 14, characterized in that The first time-frequency resource occupies available frequency domain resources of the entire channel in the frequency domain, or the communication device does not detect reservation information of other terminals in the time slot corresponding to the first time-frequency resource.

16. The device according to any one of claims 10 to 15, characterized in that The second terminal is a receiving end of the first terminal.

17. The device according to any one of claims 10 to 16, characterized in that There is a first time interval between the second time-frequency resource and the first time-frequency resource.

18. The device according to any one of claims 10 to 17, characterized in that The second time-frequency resource is reserved by the first terminal.

19. A communication device, characterized in that: The device comprises a processor, wherein the processor is coupled to a memory, wherein the memory is used to store instructions. When the program or instructions are executed by the processor, the device executes the method according to any one of claims 1 to 9.

20. A computer-readable storage medium, characterized in that: The storage medium stores a computer program or instruction. When the computer program or instruction is executed by the service quality monitoring device, the method according to any one of claims 1 to 9 is implemented.

21. A computer program product, characterized in that The computer program product comprises program instructions, and when the program instructions are executed, the method according to any one of claims 1 to 9 is implemented.

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