COMMUNICATION METHOD, COMMUNICATION DEVICE, AND COMMUNICATION SYSTEM

Abstract

The embodiments of the present application provide a communication method, a communication device, and a communication system, in which a terminal device that preempts resources on an unlicensed spectrum or can preempt resources timely implements avoidance for a terminal device that reserves resources or shares resources with a terminal device that reserves resources, and the terminal device that reserves resources can transmit data timely, which meets service requirements and significantly improves user experience.

Description

[Technical field]

[0001] The present application relates to the field of communications, and more particularly, to a communication method, a communication device, and a communication system. [Background technology]

[0002] This application claims priority to Chinese Patent Application No. 202210194217.5, entitled "COMMUNICATION METHOD, APPARATUS, AND SYSTEM," filed with the State Intellectual Property Office on March 1, 2022, the entire contents of which are incorporated herein by reference.

[0003] In wireless communication systems, the frequency bands used may be classified into licensed frequency bands (i.e., licensed spectrum) and unlicensed frequency bands (i.e., unlicensed spectrum), and enabling sidelink (SL) communication on unlicensed frequency bands in local space is an important development trend. Currently, when multiple user equipments (UEs) communicate with each other on unlicensed spectrum via sidelink, the multiple user equipments need to autonomously compete for resources, and a UE that needs to transmit data urgently may fail to obtain resources through contention. As a result, service requirements cannot be met, and user experience is seriously affected. Therefore, how to transmit data to be transmitted in a timely manner to meet service requirements is an urgent problem to be solved. Summary of the Invention

[0004] SUMMARY OF THE DISCLOSURE The embodiments of the present application provide a communication method, a communication device, and a communication system. According to this method, data can be transmitted in a timely manner to meet service requirements.

[0005] According to a first aspect, a communication method is provided, the method including: a first terminal device receiving first indication information from a second terminal device, where the first indication information indicates a first resource, the first resource being a resource reserved by the second terminal device for transmitting first data, and a resource corresponding to the first resource in a frequency domain belonging to a first channel; the first terminal device determining a second resource based on the first indication information; and the first terminal device transmitting the second data on the second resource, where a start time unit of the second resource is later than an end time unit of the first resource, and the resource corresponding to the second resource in the frequency domain belonging to the first channel; may include.

[0006] According to the method, the first terminal device postpones access to the channel, and timely implements avoidance at the time when the second terminal device accesses the channel, so that the second terminal device can transmit data on the reserved resource, which reduces data transmission delay, meets service requirements, and improves communication efficiency.

[0007] Referring to the first aspect, in some implementations of the first aspect, a first terminal device senses that a state of a first channel is idle at a first sensing time unit by using a listen-before-talk process, and interrupts the listen-before-talk process at the first sensing time unit based on a first resource, where the first sensing time unit is earlier than a start time unit of the first resource.

[0008] Referring to the first aspect, in some implementations of the first aspect, a period between the start time unit of the first resource and the first sensing time unit in which the counter value is M is less than or equal to a first threshold, where the first threshold is greater than 0 and less than a delay requirement of the second data.

[0009] In this way, the duration of the time period during which the first terminal device stops decrementing the counter is less than a certain threshold. By limiting the duration of the time period, waste of resources can be avoided because neither the first terminal device nor the second terminal device accesses the channel within the time period.

[0010] Referring to the first aspect, in some implementations of the first aspect, after incrementally reducing the value of the counter to M, the first terminal device stops the incremental reduction, where 1≦M≦Q and Q is the initial value of the counter.

[0011] Referring to the first aspect, in some implementations of the first aspect, the first threshold is determined based on a period corresponding to the second resource in the time domain.

[0012] Referring to the first aspect, in some implementations of the first aspect, the first terminal device senses that the state of the first channel is idle in the second sensing time unit and continues to progressively reduce the value of the counter from M, where the second sensing time unit is later than the end time unit of the first resource and the start time unit of the second resource is the time unit at which the value of the counter is progressively reduced to 0.

[0013] In this way, the first terminal device can access the channel after the data transmission of the second terminal device is completed, and the data to be transmitted of the first terminal device can be transmitted normally, which further meets the service requirements and avoids the waste of time-frequency resources after the resources used by the second terminal device to transmit data.

[0014] Referring to the first aspect, in some implementations of the first aspect, a first terminal device receives a first reference signal from a second terminal device, and the first terminal device determines that the power for receiving the first reference signal is greater than or equal to a reference signal reception power threshold.

[0015] After the first terminal device shares resources with the second terminal device, if the reference signal reception power of the second terminal device is lower than the threshold, another device close to the first terminal device cannot be silent. As a result, the channel may be occupied by another device, and the first terminal device cannot re-access the channel within the resource. Therefore, when the reference signal reception power of the second terminal device is equal to or greater than the reference signal reception power threshold, the first terminal device decides to implement avoidance. This prevents the resource from being preempted by devices other than the second terminal device after the first terminal device implements avoidance, improves the success rate of accessing the channel by the second terminal device, and further improves communication efficiency.

[0016] Referring to the first aspect, in some implementations of the first aspect, the first terminal device receives third indication information from the second terminal device, where the third indication information indicates that the first terminal device is a destination to which the second terminal device transmits data.

[0017] In this way, when the first terminal device is the data recipient (destination) of the second terminal device, the first terminal device can implement avoidance to the second terminal device and receive data in a timely manner, which satisfies the service requirements.

[0018] Referring to the first aspect, in some implementations of the first aspect, the first terminal device receives fourth indication information from the second terminal device, where the fourth indication information indicates a priority of the first data, and the first terminal device determines that the priority of the first data is greater than or equal to the priority of the second data.

[0019] In this way, the first terminal device implements avoidance to the device corresponding to the data with higher priority, and the service requirements of the data with higher priority can be met in a timely manner.

[0020] Referring to the first aspect, in some implementations of the first aspect, the first indication information is carried in at least one of first-stage sidelink control information, second-stage sidelink control information, a sidelink medium access control control element, or radio resource control signaling used for communication between user equipments (PC5) from a second terminal device.

[0021] Referring to the first aspect, in some implementations of the first aspect, the third indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0022] Referring to the first aspect, in some implementations of the first aspect, the fourth indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0023] It should be appreciated that the aforementioned indication information may alternatively be conveyed in signaling configured by another network device or in pre-configured signaling.

[0024] According to a second aspect, a communication method is provided, which may include: a first terminal device receiving first indication information from a second terminal device, where the first indication information indicates a first resource, and the first resource is a resource reserved by the second terminal device for transmitting first data; the first terminal device determining a third resource based on the first resource and a first channel occupation time, where the third resource belongs to the first resource and the first channel occupation time, and the third resource is used by the second terminal device to transmit data; and the first terminal device transmitting data on a fourth resource, where the fourth resource belongs to a resource other than the third resource in the first channel occupation time.

[0025] The first channel occupancy time may be a period corresponding to the fifth resource in the time domain. In other words, the first terminal device receives the first indication information from the second terminal device, where the first indication information indicates the first resource, the first resource is a resource reserved by the second terminal device to transmit the first data, the first terminal device determines the fifth resource, where the start time unit of the fifth resource is earlier than the start time unit of the first resource, the fifth resource overlaps with the first resource, the first terminal device determines the third resource based on the first resource and the fifth resource, where the third resource belongs to the overlap between the first resource and the fifth resource, the third resource is used by the second terminal device to transmit the first data, and the first terminal device transmits the second data on the fourth resource, where the fourth resource belongs to a part other than the third resource in the fifth resource.

[0026] In this method, the first terminal device shares resources with the second terminal device, and the data of the second terminal device can be transmitted in a timely manner, which meets the service requirements.

[0027] Referring to the second aspect, in some implementations of the second aspect, the first terminal device sends second display information to the second terminal device, where the second display information indicates a third resource.

[0028] In this way, the first terminal device indicates the shared resources to the second terminal device, and the second terminal device quickly determines the resources, which further reduces the delay in transmitting data by the second terminal device.

[0029] According to the second aspect, in some implementations of the second aspect, a first terminal device transmits second display information to a second terminal device within a first time period, where a start instant of the first time period falls within a range between a start time unit of a fourth resource and a start time unit of a third resource, and the period between the start instant of the first time period and the start time unit of the fourth resource is greater than or equal to a second threshold.

[0030] For example, the second threshold is T proc,0 It may be.

[0031] The first terminal device needs to ensure that there is enough time to transmit the first indication information, and the second terminal has enough time to decode the indication information. In some cases, the first indication information cannot be transmitted, or the second terminal device cannot learn the resource location when the first indication information fails to be transmitted. In this case, neither the first terminal device nor the second terminal device uses the third resource. This scheme avoids the waste of resources.

[0032] Referring to the second aspect, in some implementations of the second aspect, the first terminal device receives third indication information from the second terminal device, where the third indication information indicates that the first terminal device is a destination to which the second terminal device transmits data.

[0033] When the first terminal device is the data recipient (destination) of the second terminal device, the first terminal device can share resources with the second terminal device and receive data in a timely manner, which meets the service requirements.

[0034] Referring to the second aspect, in some implementations of the second aspect, the first terminal device receives fourth indication information from the second terminal device, where the fourth indication information indicates a priority of the first data, and the first terminal device determines that the priority of the first data is greater than or equal to the priority of the second data.

[0035] In this way, the first terminal device shares resources with devices corresponding to data with higher priority, and the service requirements of the data with higher priority can be met in a timely manner.

[0036] Referring to the second aspect, in some implementations of the second aspect, a first terminal device receives a first reference signal from a second terminal device, and the first terminal device determines that the power for receiving the first reference signal is greater than or equal to a reference signal reception power threshold.

[0037] After the first terminal device shares resources with the second terminal device, if the reference signal reception power of the second terminal device is lower than the threshold, another device close to the first terminal device cannot be silent. As a result, the channel may be occupied by another device, and the first terminal device cannot re-access the channel within the resource. Therefore, when the reference signal reception power of the second terminal device is equal to or greater than the reference signal reception power threshold, the first terminal device decides to implement avoidance. This prevents the resource from being preempted by devices other than the second terminal device after the first terminal device implements avoidance, improves the success rate of accessing the channel by the second terminal device, and further improves communication efficiency.

[0038] Referring to the second aspect, in some implementations of the second aspect, the first indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or radio resource control signaling from the second terminal device.

[0039] Referring to the second aspect, in some implementations of the second aspect, the second indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the first terminal device.

[0040] Referring to the second aspect, in some implementations of the second aspect, the third indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0041] Referring to the second aspect, in some implementations of the second aspect, the fourth indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0042] It should be appreciated that the aforementioned indication information may alternatively be conveyed in signaling configured by another network device or in pre-configured signaling.

[0043] According to a third aspect, a communication method is provided, which may include: a second terminal device transmitting first indication information, where the first indication information indicates a first resource, the first resource being a resource reserved by the second terminal device for transmitting first data; and the second terminal device transmitting the first data on a third resource, where the third resource is determined based on the first resource and a first channel occupation time, the third resource belongs to the first resource and the first channel occupation time, and a start time unit of the first channel occupation time is earlier than a start time unit of the first resource.

[0044] Referring to the third aspect, in some implementations of the third aspect, the second terminal device receives second display information from the first terminal device, where the second display information indicates a third resource.

[0045] According to the third aspect, in some implementations of the third aspect, the second terminal device receives second display information from the first terminal device within a first time period, where a start instant of the first time period falls within a range between a start time unit of a fourth resource and a start time unit of the third resource, and the period between the start instant of the first time period and the start time unit of the fourth resource is greater than or equal to a second threshold.

[0046] For example, the second threshold is T proc,0 It may be.

[0047] Referring to the third aspect, in some implementations of the third aspect, the second terminal device transmits third indication information, where the third indication information indicates that the first terminal device is a destination to which the second terminal device transmits data.

[0048] Referring to the third aspect, in some implementations of the third aspect, the second terminal device transmits a first reference signal.

[0049] Referring to the third aspect, in some implementations of the third aspect, the first indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0050] With reference to the third aspect, in some implementations of the third aspect, the second indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the first terminal device.

[0051] Referring to the third aspect, in some implementations of the third aspect, the third indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0052] Referring to the third aspect, in some implementations of the third aspect, the fourth indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or radio resource control signaling from the second terminal device.

[0053] The third aspect is an implementation of a second terminal device corresponding to the first terminal device of the second aspect, and it should be understood that the description, supplement, and beneficial effects of the second aspect are also applicable to the third aspect. Details will not be described again.

[0054] According to a fourth aspect, a communication device is provided. The communication device includes a transceiver unit and a processing unit. The transceiver unit is configured to receive first indication information from a second terminal device, where the first indication information indicates a first resource, the first resource being a resource reserved by the second terminal device for transmitting first data, and a resource corresponding to the first resource in the frequency domain belongs to a first channel. The processing unit is configured to determine a second resource based on the first indication information. The transceiver unit is further configured to transmit the second data on the second resource, where a start time unit of the second resource is later than an end time unit of the first resource, and a resource corresponding to the second resource in the frequency domain belongs to the first channel.

[0055] Referring to the fourth aspect, in some implementations of the fourth aspect, the processing unit is configured to sense that a state of the first channel is idle at a first sensing time unit by using a listen-before-talk process, and the processing unit is further configured to interrupt the listen-before-talk process at the first sensing time unit based on the first resource, where the first sensing time unit is earlier than a start time unit of the first resource.

[0056] Referring to the fourth aspect, in some implementations of the fourth aspect, a period between the start time unit of the first resource and the first sensing time unit in which the counter value is M is less than or equal to a first threshold, where the first threshold is greater than 0 and is less than a delay requirement of the second data.

[0057] Referring to the fourth aspect, in some implementations of the fourth aspect, the processing unit is configured to discontinue the incremental reduction after incrementally reducing the value of the counter to M, where 1≦M≦Q, and Q is an initial value of the counter.

[0058] Referring to the fourth aspect, in some implementations of the first aspect, the first threshold is determined based on a period corresponding to the second resource in the time domain.

[0059] Referring to the fourth aspect, in some implementations of the fourth aspect, the processing unit is further configured to determine that the state of the first channel is idle at a second sensing time unit and continue to progressively reduce the value of the counter from M, where the second sensing time unit is later than the end time unit of the first resource and the start time unit of the second resource is the time unit at which the value of the counter is progressively reduced to 0.

[0060] Referring to the fourth aspect, in some implementations of the fourth aspect, the transceiver unit is further configured to receive fourth indication information from the second terminal device, where the fourth indication information indicates a priority of the first data, and the first terminal device determines that the priority of the first data is equal to or greater than the priority of the second data.

[0061] With reference to the fourth aspect, in some implementations of the fourth aspect, the first indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or radio resource control signaling from the second terminal device.

[0062] With reference to the fourth aspect, in some implementations of the fourth aspect, the third indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or radio resource control signaling from the second terminal device.

[0063] With reference to the fourth aspect, in some implementations of the fourth aspect, the fourth indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or radio resource control signaling from the second terminal device.

[0064] The fourth aspect is an apparatus-side implementation corresponding to the first aspect, and it should be understood that the description, supplement, and beneficial effects of the first aspect are also applicable to the fourth aspect. Details will not be described again.

[0065] According to a fifth aspect, a communication device is provided. The communication device includes a transceiver unit and a processing unit. The transceiver unit is configured to receive first indication information from a second terminal device, where the first indication information indicates a first resource, and the first resource is a resource reserved by the second terminal device for transmitting first data. The processing unit is configured to determine a third resource based on the first resource and the first channel occupancy time, where the third resource belongs to the first resource and the first channel occupancy time, and the third resource is used by the second terminal device to transmit second data. The transceiver unit is further configured to transmit the first data on a fourth resource, where the fourth resource belongs to a resource other than the third resource in the first channel occupancy time.

[0066] Referring to the fifth aspect, in some implementations of the fifth aspect, the transceiver unit is further configured to transmit second indication information to a second terminal device, where the second indication information indicates a third resource.

[0067] According to the fifth aspect, in some implementations of the fifth aspect, the transceiver unit is specifically configured to transmit the second indication information to the second terminal device within a first time period, where a start instant of the first time period falls within a range between a start time unit of the fourth resource and a start time unit of the third resource, and where the period between the start instant of the first time period and the start time unit of the fourth resource is greater than or equal to a second threshold.

[0068] For example, the second threshold is T proc,0 It may be.

[0069] Referring to the fifth aspect, in some implementations of the fifth aspect, the transceiver unit is further configured to receive third indication information from the second terminal device, where the third indication information indicates that the first terminal device is a destination to which the second terminal device transmits the first data.

[0070] Referring to the fifth aspect, in some implementations of the fifth aspect, the transceiver unit is further configured to receive fourth indication information from the second terminal device, where the fourth indication information indicates a priority of the first data, and the processing unit is further configured to determine that the priority of the first data is equal to or greater than the priority of the second data.

[0071] Referring to the fifth aspect, in some implementations of the fifth aspect, the transceiver unit receives a first reference signal from a second terminal device, and the processing unit is further configured to determine that the power for receiving the first reference signal is greater than or equal to a reference signal reception power threshold.

[0072] With reference to the fifth aspect, in some implementations of the fifth aspect, the first indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or radio resource control signaling from the second terminal device.

[0073] Referring to the fifth aspect, in some implementations of the fifth aspect, the second indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the first terminal device.

[0074] Referring to the fifth aspect, in some implementations of the fifth aspect, the third indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0075] Referring to the fifth aspect, in some implementations of the fifth aspect, the fourth indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0076] The fifth aspect is an apparatus-side implementation corresponding to the second aspect, and it should be understood that the description, supplement, and beneficial effects of the second aspect are also applicable to the fifth aspect. Details will not be described again.

[0077] According to a sixth aspect, a communication device is provided. The communication device includes a transceiver unit and a processing unit. The transceiver unit is configured to transmit first indication information, where the first indication information indicates a first resource, and the first resource is a resource reserved by the second terminal device for transmitting the first data. The transceiver unit is further configured to transmit the first data on a third resource, where the third resource is determined based on the first resource and the first channel occupation time, the third resource belongs to the first resource and the first channel occupation time, and a start time unit of the first channel occupation time is earlier than a start time unit of the first resource.

[0078] Referring to the sixth aspect, in some implementations of the sixth aspect, the transceiver unit is configured to receive second indication information from the first terminal device, where the second indication information indicates a third resource.

[0079] According to the sixth aspect, in some implementations of the sixth aspect, the transceiver unit is specifically configured to receive second indication information from the first terminal device within a first time period, where a start instant of the first time period falls within a range between a start time unit of the fourth resource and a start time unit of the third resource, and where the period between the start instant of the first time period and the start time unit of the fourth resource is greater than or equal to a second threshold.

[0080] For example, the second threshold is T proc,0 It may be.

[0081] Referring to the sixth aspect, in some implementations of the sixth aspect, the transceiver unit is further configured to transmit third indication information, where the third indication information indicates that the first terminal device is a destination to which the second terminal device transmits the first data.

[0082] Referring to the sixth aspect, in some implementations of the sixth aspect, the transceiver unit is further configured to transmit a first reference signal.

[0083] Referring to the sixth aspect, in some implementations of the sixth aspect, the first indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0084] Referring to the sixth aspect, in some implementations of the sixth aspect, the second indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the first terminal device.

[0085] Referring to the sixth aspect, in some implementations of the sixth aspect, the third indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

[0086] Referring to the sixth aspect, in some implementations of the sixth aspect, the fourth indication information is carried in first stage sidelink control information, a sidelink medium access control control element, or radio resource control signaling from the second terminal device.

[0087] The sixth aspect is an apparatus-side implementation corresponding to the third aspect, and it should be understood that the description, supplement, and beneficial effects of the third aspect are also applicable to the sixth aspect. Details will not be described again.

[0088] According to a seventh aspect, there is provided a computer readable medium storing program code to be executed by a communication device, the program code including instructions used to implement a communication method according to the first aspect, the second aspect or the third aspect, any one of the possible implementations of the first aspect, the second aspect or the third aspect, or all of the possible implementations of the first aspect, the second aspect or the third aspect.

[0089] According to an eighth aspect, there is provided a computer program product comprising instructions, which when executed on a computer, enables the computer to perform a method according to the first aspect, the second aspect or the third aspect, any one of the possible implementations of the first aspect, the second aspect or the third aspect, or all of the possible implementations of the first aspect, the second aspect or the third aspect.

[0090] According to a ninth aspect, there is provided a communication system, the communication system including an apparatus configured to implement a method or functionality within various possible designs according to the first aspect, the second aspect, or the third aspect, any one of the possible implementations of the first aspect, the second aspect, or the third aspect, or all of the possible implementations of the first aspect, the second aspect, or the third aspect.

[0091] According to a tenth aspect, there is provided a processor, coupled to a memory and configured to perform a method according to the first aspect, the second aspect or the third aspect, any one of the possible implementations of the first aspect, the second aspect or the third aspect, or all of the possible implementations of the first aspect, the second aspect or the third aspect.

[0092] According to an eleventh aspect, a chip is provided. The chip includes a processor and a communication interface. The communication interface is configured to communicate with an external or internal component. The processor is configured to implement a method according to the first aspect, the second aspect, or the third aspect, any one of the possible implementations of the first aspect, the second aspect, or the third aspect, or all of the possible implementations of the first aspect, the second aspect, or the third aspect.

[0093] Optionally, the chip may further include a memory. The memory stores instructions. The processor is configured to execute instructions stored in the memory or instructions from another module. When the instructions are executed, the processor is configured to implement the method in the first aspect, the second aspect, the third aspect, or any one of their possible implementations.

[0094] Optionally, the chip may be integrated into a terminal device and / or a network device. [Brief description of the drawings]

[0095] [Figure 1]FIG. 1 illustrates a system architecture to which embodiments of the present application are applicable. [Diagram 2] 1 illustrates a slot to which an embodiment of the present application is applicable; [Diagram 3] FIG. 2 illustrates a listen-before-talk process to which embodiments of the present application are applicable. [Figure 4] FIG. 2 illustrates another listen-before-talk process to which embodiments of the present application are applicable. [Diagram 5] 1 is a diagram of a communication method according to an embodiment of the present application. [Figure 6] FIG. 2 is a diagram of transmission resources according to an embodiment of the present application. [Figure 7] 1 is a schematic flowchart of a communication method according to an embodiment of the present application; [Figure 8] FIG. 2 is a diagram of another communication method according to an embodiment of the present application. [Figure 9] 4 is a schematic flowchart of another communication method according to an embodiment of the present application. [Figure 10] FIG. 2 is a diagram of another transmission resource according to an embodiment of the present application. [Figure 11] 4 is a schematic flowchart of another communication method according to an embodiment of the present application. [Figure 12] FIG. 2 is a diagram of another transmission resource according to an embodiment of the present application. [Figure 13] 1 is a block diagram of a communication device according to an embodiment of the present application; [Figure 14] 2 is a block diagram of another communication device according to an embodiment of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0096] The following describes the technical solutions of the present application with reference to the accompanying drawings.

[0097] The technical solutions of the embodiments of the present application may be applied to various communication systems, such as 5G fifth generation (5G) or new radio (NR) systems, long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, etc. The technical solutions provided in the present application may be further applied to future communication systems, such as sixth generation mobile communication systems. The technical solutions provided in the present application may be further applied to device-to-device (D2D) communication, vehicle-to-everything (V2X) communication, machine-to-machine (M2M) communication, machine type communication (MTC), internet of things (IoT) communication systems, or other communication systems.

[0098] In addition, the technical solutions provided in the embodiments of the present application may be applied to links between network devices and terminal devices, or may be applied to links between devices, for example, device-to-device (D2D) links. The D2D link may also be referred to as a side link, and the side link may also be referred to as a side link, a secondary link, etc. In the embodiments of the present application, the D2D link, the side link, or the secondary link is a link established between devices of the same type and has the same meaning. The link between devices of the same type may be a link between terminal devices, a link between network devices, a link between relay nodes, etc. This is not limited in the embodiments of the present application. For links between terminal devices, there is a D2D link defined in Release (Rel)-12 / 13 of the 3rd generation partnership project (3GPP), and there is also a vehicle-to-everything link defined by 3GPP for the Internet of Vehicles. It should be understood that V2X specifically includes vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-pedestrian (V2P) direct communication, and vehicle-to-network (V2N), or vehicle-to-any-entity V2X links, including V2X links in Rel-14 / 15. V2X also includes NR system-based B2X links in Rel-16 and later releases currently being studied by 3GPP, etc. V2X is communication between vehicles. V2P is communication between vehicles and people (including pedestrians, cyclists, drivers, and passengers). V2I is communication between vehicles and infrastructure, where the infrastructure is, for example, a roadside unit (RSU) or a network device.In addition, V2N may be included in V2I, and V2N is the communication between vehicles and network devices. RSUs include two types: terminal type RSUs and base station type RSUs. Because terminal type RSUs are deployed on the roadside, terminal type RSUs are non-moving and mobility may not be considered. Base station type RSUs can provide timing synchronization and resource scheduling for vehicles communicating with base station type RSUs.

[0099] The following provides an architecture diagram of a mobile communication system to which an embodiment of the present application is applied. FIG. 1 is an architecture diagram of a communication system 1000 to which an embodiment of the present application is applied. As shown in FIG. 1, the communication system includes a radio access network 100. Optionally, the communication system 1000 may further include a core network 200 and an Internet 300. The radio access network 100 may include at least one radio access network device (e.g., 110a and 110b in FIG. 1) and may further include at least one terminal (e.g., 120a to 120 in FIG. 1). The terminal is connected to the radio access network device in a wireless manner, and the radio access network device is connected to the core network in a wireless manner or a wired manner. The core network device and the radio access network device may be independent, different physical devices, or the functions of the core network and the logical functions of the radio access network device are integrated into the same physical device, and some functions of the core network device and some functions of the radio access network device are integrated into one physical device. The terminals may be connected to each other in a wired or wireless manner, and the radio access network devices may be connected to each other in a wired or wireless manner. Figure 1 is just a diagram. The communication system may further include other network devices, for example, wireless relay devices and wireless backhaul devices, which are not shown in Figure 1.

[0100] It should be understood that in the communication system of the present application, the information sender may be a network device or a terminal device, and the information receiver may be a network device or a terminal device, which is not limited in the present application.

[0101] In embodiments of the present application, a UE may be referred to as a terminal device, access terminal, subscriber unit, subscriber station, mobile station, mobile console, remote station, remote terminal, mobile device, user terminal, terminal, wireless communications device, user agent, or user equipment.

[0102] A terminal device may be a device that provides voice / data to a user. For example, a terminal device may be a handheld device or a vehicle-mounted device with wireless connection capabilities. A terminal device may include user equipment, and is sometimes referred to as a terminal, an access station, a UE station, a remote station, a wireless communication device, a user equipment, etc. A terminal device may be configured to connect to a person, an object, a machine, etc., and may be widely used in various scenarios. For example, a terminal device includes, but is not limited to, terminal devices used in the following scenarios: cellular communication, D2D, V2X, machine-to-machine / machine-type communication (M2M / MTC), internet of things (IoT), virtual reality (VR), augmented reality (AR), industrial control, self driving, telemedicine, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, unmanned aerial, and robots. For example, the terminal device may be a mobile phone, a tablet computer (pad), a computer with a wireless transceiver function, a VR terminal, an AR terminal, a wireless terminal in industrial control, a vehicle, a wireless communication module in a vehicle, a vehicle-mounted T-box (telematics BOX), a roadside unit RSU, a wireless terminal in autonomous driving, a smart speaker in an IoT network, a wireless terminal device in telemedicine, a wireless terminal device in a smart grid, a wireless terminal device in road safety, a wireless terminal device in a smart city, a wireless terminal device in a smart home, etc. This is not limited to the embodiments of the present application.

[0103] By way of example and not of limitation, in the embodiments of the present application, the terminal device may alternatively be a wearable device. A wearable device may also be called a wearable intelligent device, which is a collective term for wearable devices that are intelligently designed and developed for everyday wear, such as glasses, gloves, watches, clothing, and shoes, by using wearable technology. A wearable device is a portable device that can be worn directly on the body or integrated into a user's clothing or accessories. A wearable device is not only a hardware device, but also implements powerful functions through software support, data exchange, and cloud interaction. In a broad sense, a wearable intelligent device includes a full-function large device that can implement full or partial functions without relying on a smartphone, such as a smart watch or smart glasses, and a device that focuses only on one type of application and needs to be used together with other devices such as a smartphone, such as various smart bands or smart jewelry used to monitor physical signs. In addition, the terminal device of the embodiments of the present application may alternatively be a terminal device in an IoT system. IoT is an important part of the future development of information technology. The main technological characteristic of IoT is the connection of things to a network by using communication technologies to implement intelligent networks for interconnection between people and machines or between things themselves.

[0104] When the various terminal devices described above are located in a vehicle (e.g., placed or disposed in a vehicle), all the terminal devices may be considered as vehicle-mounted terminal devices. The vehicle-mounted terminal device is also referred to as an on-board unit (OBU), for example. The terminal device in the present application may alternatively be a vehicle-mounted module, a vehicle-mounted assembly, a vehicle-mounted component, a vehicle-mounted chip, or a vehicle-mounted unit that is built into the vehicle as one or more components or units. The vehicle uses a vehicle-mounted module, a vehicle-mounted assembly, a vehicle-mounted component, a vehicle-mounted chip, or a vehicle-mounted unit that is built into the vehicle and implements the method of the present application.

[0105] It should be understood that a network device in a wireless communication system may be a device capable of communicating with a terminal device, and the network device may also be referred to as an access network device or a radio access network device. For example, the network may be a base station. The network device in the embodiment of the present application may be a radio access network (RAN) node (or device) that connects a terminal device to a wireless network. A base station may refer to various names in a broad sense or may be referred to by the following names, for example NodeB, evolved NodeB (eNB), next generation NodeB (also called gNB or future NodeB), relay station, access point, transmitting and receiving point (TRP), transmitting point (TP), master eNodeB (MeNB), secondary eNodeB (SeNB), multi-standard radio (MSR) node, home base station, network controller, access node, wireless node, access point (AP), transmitting node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (CU), etc. The base station may be replaced with a mobile station (MST) or a wireless node (DU), a positioning node, etc. The base station may be a macro base station, a micro base station, a relay node, a donor node, etc., or a combination thereof. The base station may alternatively be a communication module, a modem, or a chip disposed within the aforementioned device or apparatus.The base station may alternatively be a mobile switching center, a device implementing a base station in D2D communication, V2X communication, and M2M communication, a network side device in a future network (i.e., a future communication network), a device implementing a base station function in a future communication system, etc. The base station may support networks of the same access technology or different access technologies. The specific technology used by the network device and the specific device form are not limited in the embodiments of the present application.

[0106] In the embodiment of the present application, the base station function may be implemented by a module (e.g., a chip) in the base station, or may be implemented by a control subsystem having a base station function. The control subsystem having a base station function in this specification may be the control center of the aforementioned application scenarios, such as smart grid, industrial control, smart transportation, and smart city. The terminal function may be implemented by a module (e.g., a chip or a modem) in the terminal, or may be implemented by a device having a terminal function.

[0107] To facilitate understanding of the present application, a brief description of random access procedures and related concepts will be given.

[0108] 1. Interface: The communication interface between user equipment and network devices (Uu interface) may be referred to as the Uu interface, the communication interface between user equipment (PC5 interface) may be referred to as the PC5 interface, and the transmission link in the PC5 interface is defined as the sidelink (SL).

[0109] 2. Unlicensed spectrum: In wireless communication systems, the frequency bands used can be classified into licensed spectrum and unlicensed spectrum. On the licensed spectrum, users use spectrum resources based on the scheduling of a central node. On the unlicensed spectrum, transmitting nodes need to use spectrum resources through contention. Specifically, transmitting nodes compete for channels in a listen-before-talk (LBT) manner. In the new generation 5G NR system, the NR protocol technologies for unlicensed spectrum are collectively referred to as NR-U, and the communication performance of the corresponding Uu interface is expected to be further improved by using NR-U. Enabling SL communication over unlicensed spectrum in local space is an important development trend, and the corresponding protocol technologies may be collectively referred to as SL-U. Similar to the Uu interface, UEs working by using SL-U also need to coexist with nearby Wi-Fi devices based on the LBT mechanism. The reason why the LBT mechanism becomes an essential feature of unlicensed spectrum is because each region of the world has regulation requirements for the use of unlicensed spectrum. Various types of UEs operating in different communication protocols can use the unlicensed spectrum only if the regulations are met. In this way, the UEs can use the spectrum resources fairly and efficiently.

[0110] 3. Time domain resource: One or more time units are included in the time domain of the SL resource pool, and the time unit may be one or more symbols, one or more slots, one or more mini-slots, one or more subframes, one or more frames, etc. The one or more time units may be continuous in time or may be discrete. It should be understood that the time domain units in a resource pool are logically continuous. In the embodiment of the present application, please refer to 3GPP TS38.211 to understand the definitions of symbols, mini-slots, slots, subframes, and frames.

[0111] As shown in FIG. 2, slot 1 to slot 8 are consecutive slots in time, and the slots are called physical slots. The physical slots: slot 1, slot 3, slot 5, and slot 8 are configured as slots belonging to the same resource pool. The slots contained in a resource pool may not be consecutive in time. Thus, from the perspective of the resource pool, the physical slots: slot 1, slot 3, slot 5, and slot 8 correspond to slot 1', slot 2', slot 3', and slot 4' in the resource pool. The consecutive slots contained in the resource pool (i.e., slot 1', slot 2', slot 3', and slot 4') are consecutive slots from the logic of the resource pool, and the slots that are logically consecutive but not necessarily consecutive in time are called logical slots.

[0112] Start time unit: The start time unit is the first time unit of a resource in a time domain.

[0113] End Time Unit: The end time unit is the last time unit of a resource within a time domain.

[0114] In an example where a slot is a time unit, the resource shown in Figure 2 includes slot 1 to slot 8 in the time domain. In this example, slot 1 is the starting time unit of the resource and slot 8 is the ending time unit of the resource.

[0115] 4. Frequency domain resource: One or more frequency domain units are included in the frequency domain of the SL resource pool, and a frequency domain unit may be one or several resource elements (RE), one or several resource blocks (RB), or one or several sub-channels. The size of one sub-channel indicates the amount of one or several RBs that are included in one sub-channel and are continuous or interlaced in the frequency domain, and may be an integer number such as 10, 12, 15, 20, 25, or 50.

[0116] 5. Sidelink Resource Allocation Modes: NR SL supports two resource allocation modes: Mode 1 and Mode 2.

[0117] Mode 1 (SL mode 1): The network device allocates resources used for sidelink transmission, and mode 1 is typically for sidelink communication within the coverage area of ​​the network device.

[0118] Mode 2 (SL mode 2): The UE autonomously selects resources for sidelink transmission. Autonomous resource selection scheme: The transmitting UE autonomously selects transmission resources in the resource selection window for communication based on the sensing result in the sensing window of the transmitting UE. It is assumed that the transmitting UE triggers the resource selection in slot n. The specific resource selection procedure is as follows:

[0119] Step 1: Determine the resource selection window [n+T1, n+T2], where 0≦T1≦T(proc,1) SL ,T 2min < T2 < PDB (data packet delay), where T1 and T2 are selected based on the implementation.

[0120] Step 2: Sensing window [n-T0, nT (proc,0) SL ] to be determined.

[0121] Step 3: Determine a reference signal received power (RSRP) threshold, where the RSRP threshold and the priority prio of the data to be transmitted are TX is the priority indicated by the received sidelink control information (SCI) RX The RSRP threshold is specifically related to the (prio RX +(prio TX -1)*8)th threshold value.

[0122] Step 4: The available resource set S is selected to include all time-frequency resources (in units of one slot and one subchannel) within the resource selection window. A Initialize.

[0123] Step 5: Let S be all the periodic resources configured by the resource pool and the time-frequency resources in the reserved slots that correspond to the unsensing slots (slots in which transmissions are performed) in the sensing window. A Exclude from.

[0124] S A If the amount of time-frequency resources excluded from the resource selection window is less than X% of the total resources in the resource selection window, the initialization in step 4 is performed again.

[0125] Step 6: Select S as a time-frequency resource that satisfies the following conditions: Acontinue to exclude from the resource selection window: the decoding of the received first stage SCI is successful, the result of the RSRP measurement performed on the demodulation reference signal (DMRS) on the physical sidelink shared channel (PSSCH) corresponding to the time-frequency resource reserved by the received first stage SCI is greater than the RSRP threshold determined in step 3, and the time-frequency resource reserved by the received first stage SCI is within the resource selection window.

[0126] Step 7: A If the amount of resources remaining in the resource selection window is less than X% of the total resources in the resource selection window, where X% of the value is constituted by the resource pool, then S A The RSRP threshold determined in step 3 is increased (eg, the RSRP threshold is increased by a factor of 3 each time) until the amount of resources remaining within the resource selection window is less than X% of the total resources within the resource selection window.

[0127] For example, time-frequency resources (r0, r1, r2, ...) are assigned to S A A random selection is made from (r0, r1, r2, ...) and before data transmission, a resource reevaluation is performed for (r0, r1, r2, ...). After the reevaluation, S A Preemption detection is performed on a resource (r0', r1', r2', ...) selected from the list. The resources (r0', r1', r2', ...) are logical slots.

[0128] The user must wait at least one slot m-T3 (T3=T (proc,1) SL ), and the UE may trigger resource re-evaluation and / or preemption detection before or after slot m-T3 based on the implementation. It is determined based on steps 1 to 7 whether (r0, r1, r2, ...) and (r0', r1', r2', ...) need to be excluded.

[0129] (r0, r1, r2, ...) and r1 and / or r1' in (r0', r1', r2', ...) are S A does not belong to (i.e., r i and r i ' is not excluded during reevaluation and / or preemption detection, respectively), then r i and / or r i Slot m is the next slot in which transmission takes place, i.e. slot m belongs to (r0, r1, r2, ...) and (r0', r1', r2', ...).

[0130] 6. Channel busy ratio (CBR): The channel busy ratio indicates the ratio of the amount of channels whose sidelink-received signal strength indicator (S-RSSI) exceeds a preconfigured critical value to the total amount of channels in a preset measurement period (e.g., 100 slots or 100*2^μ slots). CBR is an indicator for measuring the degree of interference. A larger CBR indicates a higher degree of busyness of the channel, a higher system load, and stronger interference between different terminal devices. If the S-RSSI of a channel is larger than a preconfigured critical value, it indicates that the channel is occupied. If the S-RSSI of a channel is equal to or smaller than a preconfigured critical value, it indicates that the channel is not occupied. The CBR obtained by different CBR measurement methods may represent different types of channel busyness. For example, if the terminal device performs CBR measurement on three types of channels: physical sidelink feedback channel (PSFCH), PSSCH, and physical sidelink control channel (PSCCH) within a preset measurement period of 100 slots (or 100*2^μ slots), the obtained CBR represents the channel busyness of PSFCH, PSSCH, and PSCCH within the preset measurement period. If the terminal device performs CBR measurement on PSFCH, the obtained CBR indicates the busyness of one type of channel, i.e., PSFCH, within the preset measurement period. If the terminal device performs CBR measurement on two types of channels: PSSCH and PSCCH, the obtained CBR indicates the channel busyness of PSSCH and PSCCH within the preset measurement period. For detailed procedures of the terminal device performing CBR measurement on different channels and obtaining CBR, please refer to the related art. Details will not be described in this specification. In the embodiment of the present application, μ represents the sequence number of the subcarrier interval.

[0131] 7. LBT: The LBT mechanism is a channel access rule. Before accessing a channel (starting to transmit data), the UE needs to sense whether the channel is idle. If the channel is idle for a period of time, the UE can occupy the channel. If the channel is not idle, the UE can occupy the channel only after it is recovered and becomes idle again.

[0132] Generally, the channel condition can be determined using energy-based detection and signal type-based detection. For example, NR-U uses energy-based detection, and Wi-Fi uses a combination of the two detection methods. A detection threshold (energy detection threshold) needs to be set for energy-based detection. When the detected energy exceeds the detection threshold, the channel is determined to be busy, and access to the channel is not allowed. When the detected energy is lower than the detection threshold for a period of time, access to the channel is allowed. According to national and regional regulations for the use of unlicensed spectrum, when a 20 MHz channel is accessed, for example, on the 5 GHz frequency band, the 20 MHz channel can be occupied only when at least a minimum occupied channel bandwidth (OCB) requirement is met. Generally, the minimum OCB is at least 80% of the normal bandwidth. For example, when the normal bandwidth is 20 MHz, the UE needs to occupy at least 16 MHz bandwidth to preempt the 20 MHz channel.

[0133] There are several types of LBTs. Below we will explain two types of LBTs.

[0134] First type LBT: A communication device can access the channel and transmit data only after implementing a random backoff. For example, the user equipment can access the channel and transmit data only at a first time (Td , the channel may sense that it is idle and begin data transmission after progressively reducing the counter N to zero within the sensing slot duration. d followed by m p consecutive sensing slot periods (T sl Specifically, the user equipment may access a channel based on the following steps:

[0135] Step 1: N=N init where N init 0 and CW p , and perform step 2, where CW p is the contention window for channel access priority p (the contention window for a given priority class).

[0136] Step 2: If N>0, the network device or the terminal device chooses to incrementally decrement the counter and sets N=N-1.

[0137] Step 3: If the channel is idle during the sensing slot, perform step 4.

[0138] Otherwise, if the channel is not idle during the sensing slot, perform step 5.

[0139] Step 4: If N=0, stop.

[0140] Otherwise (ie, if N≠0), perform step 2.

[0141] Step 5: d until the channel is sensed busy within another period of T d The channel is sensed until all sensing slots within another period of time are sensed to be idle.

[0142] Step 6: Channel T d If idle is detected within all sensing slots within another period range of , then perform step 4.

[0143] Otherwise, the channel is T d If non-idle is detected in all sensing slots within another period range of , step 5 is performed.

[0144] CW min,p ≦CW p ≦CW max,p , where C.W. min,p is the minimum contention window for channel access priority p, and CW max,p is the minimum contention window for channel access priority p.

[0145] CW min,p and C.W. max,p is selected before step 1 above, and m p , C.W. min,p , and C.W. max,p is determined based on the channel access priority class p associated with the transmission of the network device or terminal device, as shown in Table 1.

[0146] [Table 1]

[0147] In Table 1, T m cot,p is the maximum channel occupancy time for a channel access priority p (the maximum channel occupancy time for a given priority class), and the channel occupancy time (COT) during which a network device or terminal device transmits on a channel is T m cot,pIn other words, the COT is the time during which a communication device is allowed to occupy the channel after successfully accessing the channel, or the communication device may preempt the right to use the channel within a period of time after completing the LBT process. The channel access process is performed based on a channel access priority class p associated with the transmission of the network device or terminal device. A smaller value of the priority class in Table 1 indicates a higher priority. For example, priority 1 is the highest priority.

[0148] Network devices or terminal devices are contention windows CW p value and CW based on the following steps before implementing step 1. p Adjust the value of: For each priority in the table, the CW corresponding to that priority p =CW min,p Set.

[0149] For a hybrid automatic repeat request acknowledgement (HARQ-ACK) HARQ-ACK value corresponding to data transmitted by a network device or a terminal device in a reference subframe k, if a negative acknowledgement (NACK) is fed back for at least 80% of the data, the CW corresponding to each priority is p The value of k is increased to the next higher value allowed, which is used in step 2. Otherwise, step 1 is performed. The reference subframe k is the starting subframe for the most recent data transmission of the network device or terminal device on the channel.

[0150] As shown in FIG. 3, N is used as an example of 6. The user equipment detects through sensing that the channel is the first T d Determine that the device is always in an idle state within the period range of T sl In the second T slThen, the user equipment detects that the channel state is busy, the channel state is idle, and T d After waiting for a period lasting for a third T sl The user equipment senses that the channel is busy again, the channel state is idle, and T d After waiting for a period lasting for a fourth T sl In the fifth T sl In the sixth T sl , N is progressively reduced to 0. The user equipment accesses the channel and transmits data within the COT.

[0151] The second type LBT is an LBT without random backoff, and there are two cases of the second type LBT.

[0152] Case A: After sensing that the channel is idle and the idle state persists for a period of time, the communications device may transmit data without performing a random backoff.

[0153] Case B: The transmission occurs immediately after a short switching gap. For example, the communication device transmits immediately after a switching gap in which the communication device switches from a receiving state to a transmitting state within the COT, and the duration of the switching gap is 16 μs or less.

[0154] As shown in FIG. 4, a UE may sense the channel, determine that the channel is idle within a gap, and access the channel at the end of the gap.

[0155] The time domain resource used by the UE to perform the LBT process includes one or more sensing time units. For example, one sensing time unit is 9 μs. The UE may sense the channel within the sensing time unit and perform random backoff at the same time. Note that the length of the sensing time unit is different from the length of the time unit of the time domain resource used by the UE to transmit data. For example, in an example where a slot is a time unit included in the time domain resource used by the UE to transmit data, the length of the time unit is as follows: when the subcarrier spacing is 15 kHz, the length of the time unit is 1 ms, when the subcarrier spacing is 30 kHz, the length of the time unit is 0.5 ms, etc.

[0156] In an unlicensed SL system, user equipments autonomously compete for transmission resources based on LBT, and a UE that needs to transmit data urgently may fail to obtain transmission resources through contention. For example, UE1 has a higher data priority, but the transmission resources may be preempted by other UEs. For example, according to the LBT rule, UE1's random backoff process is not completed, but the random backoff process of other UEs is completed before UE1. In this case, other UEs may access the channel first, and UE1 cannot access the channel, and UE1 will try to access the channel again based on LBT only after another UE's data transmission is completed. This cannot meet the quality of service (QoS) requirements of different services of SL on unlicensed spectrum. For example, UE1's data to be transmitted has a strict delay requirement, but UE1 cannot obtain resources through contention. As a result, data cannot be transmitted in a timely manner, and user experience is seriously affected.

[0157] In order to solve the above-mentioned problems, an embodiment of the present application provides a communication method. According to the method, data can be transmitted in a timely manner to meet service requirements. As shown in Figure 5, the method may include the following steps:

[0158] Step 501: A first terminal device receives first display information from a second terminal device.

[0159] The first indication information indicates a first resource, and the first resource is a resource reserved by the second terminal device for transmitting the first data. The first resource corresponds to a first COT in the time domain. The first resource may also be referred to as a resource reserved by the second terminal device or a reserved COT.

[0160] The first indication information may be carried in at least one of the first stage sidelink control information SCI, the second stage SCI, the sidelink media access control element (SL-MAC CE) or the PC5 interface radio resource control (PC5-RRC) signaling. For example, the first indication information may be carried only in one of the aforementioned signalings. Alternatively, the first indication information may be carried in a plurality of the aforementioned signalings. For example, the complete content of the first indication information may be carried in the SL-MAC CE and may be carried in the PC5-RRC signaling. Alternatively, the content of the first indication information may be jointly indicated by using a plurality of signalings. For example, a part of the content of the first indication information is carried in the first stage SCI, and another part of the content is carried in the PC5-RRC signaling. This is not limited in the embodiment of the present application.

[0161] It should be understood that the first indication information may alternatively be carried in a signaling configured or preconfigured by another network device. For example, a resource reservation period field indicates a resource periodically reserved for data transmission, and a value of the resource reservation period field may be configured, predefined, or predefined by the network device. For example, the network device may indicate the periodic resource through RRC signaling, and the RRC signaling includes periodic information (sl-ResourceReservePeriod1). This is not limited to this embodiment of the application.

[0162] For example, the first indication information is carried in the first stage SCI. In this case, a frequency domain resource assignment field and a time domain resource assignment field in the first stage SCI indicate the frequency domain resource and the time domain resource used by the first terminal device to transmit data, respectively. After decoding the first stage SCI, the second terminal device may determine the first resource.

[0163] The first indication information may indicate the LBT time-frequency starting location of the second terminal device. The LBT time-frequency starting location may be understood as the starting location of the time-frequency resource used by the second terminal device to perform the LBT process. Alternatively, the first indication information may indicate the time-frequency starting location of the COT reserved by the second terminal device.

[0164] When the first indication information indicates the LBT time-frequency start location of the second terminal device, the second terminal device is further required to indicate an LBT parameter to the first terminal device, and the first terminal device determines the first resource based on the LBT parameter. It should be understood that the LBT parameter is the LBT parameter of the second terminal device. The LBT parameter of the second terminal device is an LBT counter, for example, a total amount of backoff time N init and a current value of the counter N. The LBT parameters may further include an LBT channel access priority p.

[0165] The LBT parameters may be carried in the second stage SCI, for example, in SCI format 2-D. The second stage SCI format may be indicated by using the first stage SCI, and possible second stage SCI format fields are shown in Table 2.

[0166] [Table 2]

[0167] It should be understood that Table 2 is used merely as an example instead of a limitation. Some contents in Table 2 may be used for implementation, all contents in Table 2 may be used for implementation, or Table 2 may be used as a part of other contents for implementation. This is not a limitation in this embodiment of the present application.

[0168] Optionally, the second terminal device may send display information (i.e., third display information) to the first terminal device, where the display information indicates that the first terminal device is the destination to which the second terminal device transmits data. For example, the display information may include the identification (identification document, ID) of the sender and destination of the data to be transmitted, where the sender's ID (sender ID) is the ID of the second terminal device, and the destination's ID (destination ID) is the ID of the first terminal device. Alternatively, the display information may include the ID of the second terminal device. Alternatively, the display information may include the ID of the second terminal device and the ID of the first terminal device. After receiving the display information, the first terminal device may determine that the first terminal device and the second terminal device are both parties to the data transmission.

[0169] Alternatively, the display information may include a temporary user group identification (temporary UE group ID, hereinafter abbreviated as group ID), and the temporary user group is a group predefined by the network device. For example, the network device groups UE1 and UE2 into the same group. Alternatively, the display information may include a cell ID, where the cell may be a cell in which UE1 and UE2 coexist in a geographical sense, the cell may be a cell obtained through division based on the scheduling range of the network device, or the cell may be a cell predefined by the network device. The first terminal device is further required to receive the same content of display information from the network device. For example, the first terminal device receives a group ID from the network device and then receives the same group ID from the second terminal device, and the first terminal device may determine that the first terminal device and the second terminal device have the same group ID. The network device may predefine that the IDs included in the temporary group are the IDs of both parties of the data transmission. In this case, the first terminal device may determine that the first terminal device and the second terminal device are both parties to the data transmission.

[0170] Alternatively, the network device may pre-configure the correspondence between the first terminal device and the second terminal device. For example, the network device may pre-configure in the first terminal device a table of correspondence between the potential interaction peers of the first terminal device and the first terminal device. When receiving the ID sent by the second terminal device, the first terminal device may determine that the second terminal device is a peer that interacts with the first terminal device.

[0171] The third indication information may be carried in at least one of the first stage SCI, the second stage SCI, the SL-MAC CE, or the PC5-RRC signaling. It should be understood that the above manner of indicating both parties of data transmission is only an example, not a limitation. For the manner of carrying the third indication information, please refer to the related description of the first indication information. Details will not be described again.

[0172] The second terminal device is further required to transmit data priority indication information (ie, the fourth indication information) to the first terminal device, and indicate the priority of the data to be transmitted by the second terminal device. The priority indication information can be carried in at least one of the first stage SCI, the second stage SCI, the SL-MAC CE, or the PC5-RRC signaling. For the manner of carrying the fourth indication information, please refer to the related description of the first indication information. Details will not be described again.

[0173] It should be understood that the first indication information and the fourth indication information may be transmitted in a broadcast manner, a multicast manner, or a unicast manner, which is not limited in this embodiment of the present application.

[0174] Step 502: The first terminal device determines a second resource based on the first display information.

[0175] The first terminal device may determine the second resource based on the first resource indicated by the first indication information. For example, the first terminal device determines the second resource based on the time domain location of the first resource. Specifically, if the first terminal device determines a part of a resource and the time domain location of the resource is after the time domain location of the first resource and does not overlap with the time domain location of the first resource, the part of the resource may be the second resource.

[0176] Optionally, the first terminal device may further sense that the state of the first channel is idle at the first sensing time unit, and interrupt the listen-before-talk process at the first sensing time unit based on the first resource, where the first sensing time unit is earlier than the start time unit of the first resource.

[0177] The first terminal device suspending listen-before-talk processing at the first sensing time unit based on the first resource may be understood to mean that after determining the first resource, the first terminal device suspends listen-before-talk processing at the first sensing time unit based on the time domain location of the first resource.

[0178] For example, when the first terminal device receives the LBT time-frequency start location and the LBT parameter information, the first terminal device needs to determine the time-frequency location of the first resource based on the LBT time-frequency start location and the LBT parameter information. For example, the first terminal device needs to determine the total amount of LBT backoff time N init and the current value N of the counter, calculate the period required for the value of the counter in the second terminal device to be gradually reduced from N to 0. Then, the first terminal device determines the LBT time-frequency end location based on the LBT time-frequency start location and the period, where the LBT time-frequency end location is the start location (start time unit) of the first resource.

[0179] The first terminal device interrupting the listen-before-talk process can be understood as the first terminal device stopping or temporarily stopping the process of accessing the channel. In other words, the first terminal device does not access the channel in the time domain range corresponding to the first resource, or the first terminal device can stop gradually reducing the value of the counter, for example, after gradually reducing the value of the counter from Q to M, the first terminal device stops the gradual reduction, where 1≦M≦Q and Q is the initial value of the counter.

[0180] Before suspending the listen-before-talk process, the first terminal device is further required to determine at least one of the following:

[0181] A. The priority of the data to be transmitted from the second terminal device is higher than the priority of the data to be transmitted from the first terminal device.

[0182] The first terminal device may determine a priority relationship based on the fourth display information in step 501 and the data priority of the first terminal device.

[0183] B. The RSRP of the reference signal transmitted by the second terminal device is greater than the RSRP threshold determined by the first terminal device.

[0184] According to the LBT rule, after preempting the channel, the first terminal device allows UEs within a certain RSRP threshold range to go silent based on the strength of the signal transmitted by the first terminal device. These UEs cannot complete the LBT backoff process because they detect that the channel is busy. If the RSRP of the UE is low, it indicates that the distance between the UE and the first terminal device is long. After the first terminal device shares resources with the second terminal device, the second terminal device cannot allow another device close to the first terminal device to go silent due to the low RSRP of the second terminal device. As a result, the channel may be occupied by another device. Therefore, when the RSRP of the reference signal transmitted by the second terminal device is greater than the RSRP threshold determined by the first terminal device, data cannot be transmitted normally.

[0185] The second terminal device may transmit a reference signal to the first terminal device. For example, the reference signal may be carried in the first stage SCI, and the reference signal may be a PSCCH DMRS. Alternatively, the reference signal may be a reference signal on the PSSCH, for example, a PSSCH DMRS. The first terminal device obtains the received power of the reference signal by measuring the first stage SCI. For determining the RSRP threshold, please refer to the related description in SL mode 2. Details will not be described again.

[0186] C. The starting time unit of the first resource is later than the starting time unit of the resource to be preempted by the first terminal device.

[0187] The resource to be preempted by the first terminal device can be understood to be the time-frequency resource to be occupied by the first terminal device after the first terminal device completes backoff based on the current LBT process. As shown in (a) of FIG. 6, the resource to be preempted by the first terminal device is T UE1S and T UE1EThe time-frequency resource between

[0188] D. The period between the start time unit of the first resource and the first sensing time unit in which the counter has a value of M is less than or equal to a first threshold, where 1≦M≦N, and N is the value of the counter at which the progressive reduction is discontinued.

[0189] The first threshold value may be greater than 0 and is less than the delay required by the data to be transmitted of the first terminal device. In other words, there is an upper limit on the period during which the first terminal device stops incrementally reducing the counter. That is, the first terminal device determines that the incremental reduction is interrupted if the period during which the incremental reduction is interrupted is equal to or less than the upper limit, and the value of the counter at the time when the incremental reduction is interrupted may not be taken into account. In other words, the moment when the first terminal device decides to interrupt the incremental reduction may be the moment when the value of the counter is greater than 0 at that time and the upper limit is met at that time. The first threshold value may be a value configured by the network device, a preconfigured value, or a fixed value predefined in a standard protocol. This is not limited in this embodiment of the present application.

[0190] The first terminal device stops decrementing the counter incrementally, which can be understood as the first terminal device stops decrementing the counter incrementally from the moment, and the value of the counter remains at the value of the counter before the incremental decrement. In addition, the minimum value of the counter is limited to 1. According to the LBT rule, it means that the first terminal device cannot access the channel to transmit data.

[0191] The first perceptible time unit in which the counter has a value of M is the perceptible time unit in which the moment when the reduction starts is located (i.e., the first perceptible time unit). For example, the gradual reduction is interrupted in perceptible time unit 1, and the value of the counter is 2 in this case. Before the start unit of the first resource, perceptible time unit 2 and perceptible time unit 3 are further included, and the value of the counter in perceptible time unit 2 and the value of the counter in perceptible time unit 3 are always 2. In this case, the first perceptible time unit in which the counter has a value of 2 is perceptible time unit 1. It should be understood that the above values ​​and indexes are not limiting but are merely examples.

[0192] It should be appreciated that the first terminal device is further required to successfully decode the first stage SCI.

[0193] Optionally, the first terminal device may further determine, based on the third indication information, that the second terminal device is a destination to which the first terminal device transmits information (data).

[0194] Optionally, the first terminal device may further determine a CBR of the first channel. When the CBR is equal to or less than a third threshold, the first terminal device may interrupt the LBT process. The CBR represents the busyness of the first channel within a first preset period. For example, the first preset period is a preset measurement period, for example, 100 slots, 100 Ts, and the like. sl , or 100 T d (or 100*2 μ Slot / T sl / T d ).

[0195] Alternatively, the first terminal device may be configured to select a preset measurement period, for example 100 T sl (T d ) or 100*2 μ T's sl (T d) whose energy detection result is greater than the energy detection threshold T sl (T d ) amount of T sl (T d ) to the total amount of energy detected, where the energy detection threshold is X Thresh It can be the channel energy detection result or T sl (T d ) is greater than the energy detection threshold, it is a channel or T sl (T d ) is occupied. If the energy detection result of the channel is below the energy detection threshold, it indicates that the channel or T sl (T d ) is not occupied. When the ratio is equal to or less than a third threshold, the first terminal device may interrupt the LBT process.

[0196] The third threshold value can be predefined. For example, the third threshold value can be 20%. This is not limited in this embodiment of the present application. It should be understood that in the time domain, the first preset period or the preset measurement period is before the slot at which the moment when the first terminal device interrupts the LBT process is located.

[0197] Optionally, the first terminal device may further perform re-evaluation or preemption detection on the resources. For example, after the sensing window, the first terminal device may perform re-evaluation or preemption detection on the time domain resources before the second terminal device accesses the channel. For example, the first terminal device may perform re-evaluation or preemption detection on the time domain resources in (r0, r1, r2, ...) and (r0', r1', r2', ...). i and / or r i ' is S A Belongs to / does not belong to (i.e., r i and r i ' is excluded during reevaluation and / or preemption detection, respectively). In this case, i and / or r iIt may be determined that the second terminal device ' can be used to transmit data. Before performing re-evaluation or preemption detection, the first terminal device may determine a sensing window, a selection window, and a reference signal reception power threshold, and initialize an available resource set. For details, please refer to the description of steps 1 to 4 of SL mode 2. Details will not be described again.

[0198] The aforementioned channel can be understood to be a bandwidth. For example, in an unlicensed SL communication system, there are multiple access channels with 20MHz bandwidth, and the UE can perform LBT access for each 20MHz channel separately, and the access process of the channels is independent of each other. After completing the LBT, the UE occupies the corresponding 20MHz bandwidth. It should be understood that 20MHz is only an example of a channel in this embodiment of the present application, not a limitation. For example, the channel in this embodiment of the present application can be another bandwidth, such as 30MHz, 40MHz, or 45MHz, as an alternative.

[0199] Step 503: The first terminal device transmits data on the second resource.

[0200] The start time unit of the second resource is later than the end time unit of the first resource. As shown in FIG. 6(b), T* UE1S is T UE2E That is, the first terminal device accesses the channel to transmit data after the second terminal device finishes transmitting data. It should be understood that the first terminal device defers channel access or spares the use of resources reserved by the second terminal device through avoidance.

[0201] The first threshold value in step 502 may be determined based on the duration of the second resource. For example, the first threshold value may be 1 / 10, 1 / 8, etc. of the duration of the second resource.

[0202] A possible implementation of the first terminal device accessing the second resource is as follows: the first terminal device determines that the channel state is idle in the second sensing time unit and continues to progressively decrement the counter, where the second sensing time unit is later than the end time unit of the first resource, and the first terminal device progressively decrements the counter to 0 in the start time unit within the second resource and accesses the channel to transmit data.

[0203] Continuing to incrementally decrease the counter means that the value of the counter at which this time of incremental decrease begins is the value of the counter when the incremental decrease is interrupted in step 502. For example, in step 502, the value of the counter is 2 when the incremental decrease is interrupted, and the value of the counter is now incrementally decreased from 2 to 0. It should be understood that this value is not limiting, but merely an example. According to the LBT rules, the incremental decrease of the counter to 0 means that the first terminal device accesses the channel to transmit data.

[0204] Alternatively, the first terminal device may determine that the channel is idle for a time period, and the first terminal device accesses the channel. The duration of this time period may be 16 μs, etc. For details, please refer to the description of the second-type listen-before-talk. The details will not be described again.

[0205] Optionally, the first terminal device may further perform sensing at the start time unit of the first resource to determine whether the second terminal device successfully accesses the channel. If the second terminal device successfully accesses the channel, the first terminal device accesses the channel and transmits data as in step 503. Otherwise, the first terminal device directly continues the LBT process, and accesses the channel after the LBT process is completed.

[0206] It should be understood that the transmission of data on the first channel by the first terminal device may be understood to be an example of a sidelink transmission performed by the first terminal device on the first channel. The first terminal device may transmit or receive sidelink control information and / or feedback information, etc. on the first channel.

[0207] In this method, devices that can preempt resources implement avoidance in the time domain, and devices with higher data priority can transmit data on the reserved resources in a timely manner, which meets service requirements and significantly improves user experience.

[0208] An embodiment of the present application provides a communication method. As shown in Figure 7, it is used as an example that the first indication information and the fourth indication information are carried in the first stage SCI, UE1 is an example of a first terminal device, UE2 is an example of a second terminal device, COT1 is an example of a first resource, COT2 is an example of a second resource, SCI#A is an example of a first stage SCI, and SCI#B is an example of a second stage SCI. The method may include the following steps:

[0209] Step 701: UE2 sends SCI#A to UE1, and correspondingly, UE1 receives SCI#A.

[0210] SCI#A is carried on the PSCCH. SCI#A includes resource indication information, data priority information, reference signal, and format of SCI#B. Specifically, please refer to the related description of the first indication information and the fourth indication information in step 501. Details will not be described again.

[0211] Step 702: UE2 sends SCI#B to UE1, and correspondingly, UE1 receives SCI#B.

[0212] SCI#B is carried on the PSSCH. SCI#B includes the LBT parameters of UE2.

[0213] Step 703: UE1 determines COT1 based on SCI#A and SCI#B.

[0214] Step 704: UE1 determines that an avoidance condition is met.

[0215] For the avoidance conditions, please refer to the relevant explanations of A, B, C, and D in step 502. The details will not be described again.

[0216] Optionally, UE1 may perform resource re-evaluation or preemption detection. For details, please refer to the description of step 502. The details will not be described again.

[0217] Step 705: UE1 stops progressively decrementing the counter in sensing time unit #A.

[0218] For example, when the gradual reduction is interrupted, the value of the counter is 3. For step 703, please refer to the related description of step 502. The details will not be described again.

[0219] Step 706: UE2 accesses the channel at the start time unit of COT1.

[0220] Step 707: UE1 performs sensing at the start time unit of COT1 and determines that the channel state is busy.

[0221] Step 708: UE1 determines that the channel state is idle in sensing time unit #B, continues to gradually decrement the counter, and gradually decrements the counter to 0 at the start time unit of COT2.

[0222] For example, UE1 gradually decreases the counter from 3. For step 707, please refer to the related description of step 503. The details will not be described again.

[0223] Step 709: UE1 sends data in COT2.

[0224] It should be understood that before step 701, UE1 may determine a sensing window and a selection window and select a resource. Details are not described in this specification. For specific steps, please refer to the above description of steps 1 to 7 of mode 2 (SL mode 2).

[0225] In this method, when the avoidance condition is met, UE1 suspends LBT backoff process, does not access the channel, waits for UE2 to access the channel to transmit data, and accesses the channel to transmit data after UE2 finishes transmitting data. In this way, UE2's data can be transmitted in a timely manner, which meets the service requirements.

[0226] In the above method, the device that can preempt the resource can implement the avoidance, and the data with higher priority can be transmitted in a timely manner. The embodiment of the present application provides another communication method. The device that preempted the resource can share the resource with the device that should transmit the data, and the data can be transmitted normally. The following describes the method in detail. As shown in Figure 8, the method may include the following steps.

[0227] Step 801: A first terminal device receives first display information from a second terminal device.

[0228] The first indication information indicates a first resource, and the first resource is a resource reserved by the second terminal device to transmit the first data. For the first indication information, please refer to the description of the first indication information and the first resource in step 501. Details will not be described again in this specification.

[0229] The relationship between the first terminal device and the second terminal device can be divided into two cases.

[0230] Case 1: A first terminal device is a destination to which a second terminal device transmits data.

[0231] In this case, the second terminal device needs to send display information (i.e., third display information) to the first terminal device, where the display information indicates that the first terminal device is the destination to which the second terminal device transmits data. For example, the display information may include the identification (identification document, ID) of the sender and destination of the data to be transmitted, where the sender's ID (sender ID) is the ID of the second terminal device, and the destination's ID (destination ID) is the ID of the first terminal device. Alternatively, the display information may include the ID of the second terminal device. Alternatively, the display information may include the ID of the second terminal device and the ID of the first terminal device. After receiving the display information, the first terminal device may determine that the first terminal device and the second terminal device are both parties to the data transmission.

[0232] Alternatively, the display information may include a temporary user group identification (temporary UE group ID, hereinafter abbreviated as group ID), and the temporary user group is a group predefined by the network device. For example, the network device groups UE1 and UE2 into the same group. Alternatively, the display information may include a cell ID, where the cell may be a cell in which UE1 and UE2 coexist in a geographical sense, the cell may be a cell obtained through division based on the scheduling range of the network device, or the cell may be a cell predefined by the network device. The first terminal device is further required to receive the same content of display information from the network device. For example, the first terminal device receives a group ID from the network device and then receives the same group ID from the second terminal device, and the first terminal device may determine that the first terminal device and the second terminal device have the same group ID. The network device may predefine that the IDs included in the temporary group are the IDs of both parties of the data transmission. In this case, the first terminal device may determine that the first terminal device and the second terminal device are both parties to the data transmission.

[0233] Alternatively, the network device may pre-configure the correspondence between the first terminal device and the second terminal device. For example, the network device may pre-configure in the first terminal device a table of correspondence between the potential interaction peers of the first terminal device and the first terminal device. When receiving the ID sent by the second terminal device, the first terminal device may determine that the second terminal device is a peer that interacts with the first terminal device.

[0234] The third indication information may be carried in at least one of the first phase SCI, the second phase SCI, the SL-MAC CE, or the PC5-RRC signaling. For the second phase SCI, see the related description of step 501. It should be understood that the above manner of indicating both parties of the data transmission is merely an example, not a limitation.

[0235] Case 2: The first terminal device and the second terminal device are not both parties in the data transmission.

[0236] In this case, the first terminal device does not need to determine whether the second terminal device is the peer side of data transmission. Optionally, the first terminal device can receive data priority indication information (i.e., the fourth indication information) from the second terminal device, and the first terminal device determines that the priority of the data transmitted by the second terminal device is equal to or higher than the priority of the data transmitted by the first terminal device. Specifically, for the fourth indication information, please refer to the relevant description of step 501. Details will not be described again.

[0237] Optionally, the first terminal device further receives a reference signal from the second terminal device, and the first terminal device determines that the power for receiving the reference signal is equal to or greater than the reference signal receiving power threshold.Specifically, please refer to the relevant description of the content B of step 502.Details will not be described again.

[0238] Step 802: The first terminal device determines a third resource based on the first resource and the first channel occupancy time.

[0239] The first channel occupation time (COT) is a time domain resource corresponding to the fifth resource in the time domain, and the fifth resource is a resource preempted by the first terminal device. For example, if the first terminal device accesses (transmits data) a channel earlier than the second terminal device, the channel usage period that the first terminal device is allowed to occupy is the first channel occupation time. Within the first COT, the first terminal device may transmit data by using a time-frequency resource (the fifth resource). In other words, the first terminal device determines the third resource based on the first resource and the fifth resource.

[0240] The third resource is used by the second terminal device to transmit data, and the third resource belongs to the first resource and the first channel occupation time. Since the start instant (start time unit) of the first channel occupation time is earlier than the start instant (start time unit) of the first resource, the third resource belonging to the first resource and the first channel occupation time can be understood as the third resource belonging to the intersection or overlap between the first resource and the first channel occupation time. In other words, the third resource belongs to the overlap between the first resource and the fifth resource. The third resource may be an overlap between the first resource and the first channel occupation time, that is, the resource corresponding to the third resource in the time domain can be understood as the intersection between the resource corresponding to the first resource in the time domain and the first channel occupation time. Alternatively, the third resource may be part of the overlap between the first resource and the first channel occupancy time, i.e., the resource corresponding to the third resource in the time domain falls within the range of intersection between the resource corresponding to the first resource in the time domain and the first channel occupancy time.

[0241] Optionally, after determining the third resource, the first terminal device transmits second indication information to the second terminal device, where the second indication information indicates the third resource. Further, the first terminal device transmits the second indication information to the second terminal device within a first time period, where a start instant of the first time period falls within a range between a start time unit of the fourth resource and a start time unit of the third resource, and a period between the start instant of the first time period and a start time unit of the fourth resource is equal to or greater than a second threshold. For example, the second threshold is T proc,0 That is, the first terminal device needs to indicate information about the third resource to the second terminal device before the start time unit of the third resource.

[0242] That is, in case 1 of step 801, the first terminal device needs to determine at least one of the following contents:

[0243] E: The first terminal device is a destination device for which the second terminal device reserves resources for transmission; F: The start location of the first resource is after the start location of the fifth resource and the first resource overlaps with the fifth resource; and G: The first terminal device has enough time to transmit the second indication information.

[0244] In case 2 of step 801, the first terminal device needs to determine at least one of the following:

[0245] H: the priority of the data to be transmitted of the second terminal device is higher than the priority of the data to be transmitted of the first terminal device; I: The start location of the first resource is after the start location of the fifth resource and the first resource overlaps with the fifth resource; J: the first terminal device has sufficient time to transmit the second indication information; and K: The RSRP of the first resource is greater than the RSRP threshold.

[0246] It should be appreciated that the first terminal device is further required to successfully decode the first stage SCI.

[0247] According to the LBT rule, after preempting the channel, the first terminal device allows UEs within a certain RSRP threshold range to go silent based on the strength of the signal transmitted by the first terminal device. These UEs cannot complete the LBT backoff process because they detect that the channel is busy. If the RSRP of the UE is low, it indicates that the distance between the UE and the first terminal device is long. After the first terminal device shares resources with the second terminal device, the second terminal device cannot allow another device close to the first terminal device to go silent due to the low RSRP of the second terminal device. As a result, the channel may be occupied by another device, the second terminal device cannot transmit data, and the first terminal device cannot re-access the channel. Therefore, when the RSRP of the reference signal transmitted by the second terminal device is greater than the RSRP threshold determined by the first terminal device, data cannot be transmitted normally. Specifically, please refer to the content B of step 502. Details will not be described again.

[0248] Optionally, the first terminal device may perform resource re-evaluation or preemption detection. For details, please refer to the description of step 502. The details will not be described again.

[0249] The second indication information can be carried in at least one of the first stage SCI, the second stage SCI, the SL-MAC CE, or the PC5-RRC signaling. Specifically, for the manner of carrying the second indication information, please refer to the related description of the first indication information. Details will not be described again.

[0250] Step 803: The first terminal device transmits first data on a fourth resource, where the fourth resource belongs to a resource other than the third resource within the first channel occupancy time.

[0251] The fourth resource belongs to resources other than the third resource in the fifth resource, which may be understood to mean that the fourth resource may be all resources other than the third resource in the fifth resource, or the fourth resource may be a part of resources other than the third resource in the fifth resource.

[0252] It can be further understood that the start instant (start time unit) of the third resource is later than the start instant of the fifth resource, which means that the first terminal device has transmitted part of data on the resource before the third resource. After the second terminal device completes data transmission on the third resource, the first terminal device re-accesses the channel and transmits data on the resource after the third resource. Before accessing the channel, the first terminal device may sense the channel. For example, if the channel is determined to be idle in a time period, the first terminal device may access the channel. For details, please refer to the description of the second type listen-before-talk. Details will not be described again. Alternatively, the first terminal device may access the channel within a time period based on the first type listen-before-talk. This is not limited in this embodiment of the present application.

[0253] In a possible implementation, the fourth resource belonging to a resource other than the third resource in the first channel occupancy time can be understood to mean that the fourth resource is a frequency domain resource other than the frequency domain resource corresponding to the third resource in the first channel occupancy time, i.e., the first terminal device and the second terminal device transmit data simultaneously on the time domain resource corresponding to the third resource, but the frequency domain resources used by the first terminal device and the second terminal device to transmit data do not overlap.

[0254] In this method, the device that preempted the resource shares the resource with a device that has a higher data priority, or shares the resource with a device that is a sender for data transmission with the device that preempted the resource, and the device with the higher data priority can transmit data in a timely manner, which meets the service requirements and improves the user experience.

[0255] An embodiment of the present application provides a communication method. As shown in Figure 9, an example is used in which the first indication information, the third indication information, and the fourth indication information are carried in the first stage SCI, UE1 is an example of a first terminal device, UE2 is an example of a second terminal device, COT1 is an example of a first resource, COT3 is an example of a third resource, COT4 is an example of a fourth resource, COT5 is an example of a fifth resource, SCI#C is an example of a first stage SCI, and SCI#D is an example of a second stage SCI. It should be understood that the period of one COT includes a period for transmitting a PSCCH and a period for transmitting a PSSCH. The method may include the following steps.

[0256] Step 901: UE2 sends SCI#C to UE1, and correspondingly, UE1 receives SCI#C.

[0257] SCI#C is carried on PSCCH. SCI#C is the first-stage SCI. SCI#C includes resource indication information, reference signal, and format of SCI#D. Specifically, for resource indication information, please refer to the related description of the first indication information in step 801. For reference signal and format of SCI#D, please refer to the related description in step 801. Details will not be described again.

[0258] Optionally, when UE2 and UE1 are not both parties to the data transmission at this time, SCI#C may include the priority of UE2's data to be transmitted.

[0259] Step 902: UE2 sends SCI#D to UE1, and correspondingly, UE1 receives SCI#D.

[0260] SCI#D is carried on the PSSCH. SCI#D is the second stage SCI. SCI#D includes the LBT parameters of UE2.

[0261] When UE2 and UE1 are both parties of data transmission at this time, SCI#D further includes the ID of UE2 and the ID of UE1. For these IDs, please refer to the description of the third display information in step 801. For SCI#D, please refer to the description of the second stage SCI in step 501. Details will not be described again.

[0262] When UE2 and UE1 are not both parties to the data transmission at this time, SCI#D may not include UE2's ID and UE1's ID.

[0263] Optionally, UE1 may perform resource re-evaluation or preemption detection. For example, UE1 may perform resource re-evaluation or preemption detection from T1 to T proc,1 SL Resource re-evaluation or preemption detection may be performed until the end of the process. For details, please refer to the description of step 502. The details will not be described again.

[0264] Step 903: UE1 sends data in COT5.

[0265] As shown in Figure 10, UE1 accesses the channel (transmits data) in T1. The resource between T1 and T2 in Figure 10 is the fifth resource in step 802.

[0266] Step 904: UE1 determines COT1 based on SCI#C and SCI#D.

[0267] As shown in Figure 10, COT1 is the period between T3 and T4. Specifically, for COT1, please refer to the description of the first resource in step 802. Details will not be described again. In other words, the resource between T3 and T4 is the first resource in step 801.

[0268] Step 905: UE1 determines that an avoidance condition is met.

[0269] When UE2 and UE1 are both parties in this time of data transmission, for the avoidance conditions, please refer to the related description of E, F, and G in step 802. When UE2 and UE1 are not both parties in this time of data transmission, for the avoidance conditions, please refer to the related description of H, I, J, and K in step 802. Details will not be described again.

[0270] Step 906: UE1 sends the second display information to UE2.

[0271] As shown in Figure 10, UE1 transmits second indication information to UE2 during T5 and T6. The second indication information indicates COT3. For example, the second indication information may include a start location T8 of COT3 and a length L of COT3. Alternatively, the second indication information may include a start location T8 of COT3 and an end location T9 of COT3.

[0272] Step 907: UE1 stops transmitting data at T7.

[0273] Step 908: UE2 determines that the channel condition between T7 and T8 is idle.

[0274] Optionally, UE2 may determine that the channel condition between T7 and T8 is idle based on a second type listen-before-talk mechanism.

[0275] Step 909: UE2 starts transmitting data at T8.

[0276] 10, UE2 transmits data between T8 and T9. In other words, the resource between T8 and T9 is the third resource in step 802.

[0277] Step 910: UE1 determines that the channel condition between T9 and T10 is idle.

[0278] Optionally, UE1 may determine that the channel condition between T9 and T10 is idle based on a second type listen-before-talk mechanism.

[0279] Step 911: UE1 starts transmitting data at T10.

[0280] Optionally, as shown in FIG. 10, UE1 may end data transmission at T2, that is, the resources between T1 and T7 and the resources between T10 and T2 are the fourth resources in step 803.

[0281] It should be understood that before step 901, UE1 may determine a sensing window and a selection window and select a resource (COT5). Details will not be described herein. For specific steps, please refer to the above description of steps 1 to 7 of mode 2 (SL mode 2). It should be further understood that Figure 10 is intended to describe the relationship in the time domain, and the multiple COTs in the figure are drawn separately for ease of understanding only, and no distinction in the frequency domain is required.

[0282] In this method, UE1, which has preempted resources, serves as a receiver for UE2, or when the data priority of UE2 is higher than that of UE1, UE1 shares part or all of the preempted resources with UE2, and UE2 can transmit data in a timely manner, which meets the service requirements and improves communication efficiency.

[0283] In the method shown in Figures 5 to 10, the resources preempted by the first terminal device and the resources reserved by the second terminal device are on the same channel. It should be understood that the resources preempted by the first terminal device and the resources reserved by the second terminal device may alternatively be on different channels, or some frequency domain resources in the resources reserved by the second terminal device are on the same channel as the resources preempted by the first terminal device, and other frequency domain resources reserved by the second terminal device are on a different channel from the resources preempted by the first terminal device. This is not limited in the present application.

[0284] An embodiment of the present application provides a communication method. As shown in Figure 11, it is used as an example that the first indication information and the fourth indication information are carried in the first stage SCI, UE1 is an example of a first terminal device, UE2 is an example of a second terminal device, COT1 is an example of a first resource, COT2 is an example of a second resource, SCI#E is an example of a first stage SCI, and SCI#F is an example of a second stage SCI. The method may include the following steps:

[0285] Step 1101: UE2 sends SCI#E to UE1, and correspondingly, UE1 receives SCI#E.

[0286] SCI#E is carried on PSCCH. SCI#E includes resource indication information, data priority information, reference signal, and format of SCI#F. Specifically, please refer to the related description of the first indication information and the fourth indication information in step 501. Details will not be described again.

[0287] Step 1102: UE2 sends SCI#F to UE1, and correspondingly, UE1 receives SCI#F.

[0288] SCI#F is carried on the PSSCH. SCI#F contains the LBT parameters of UE2.

[0289] Step 1103: UE1 determines a first resource based on SCI#E and SCI#F.

[0290] As shown in FIG. 12, the first resource is a time-frequency resource on channel #3 within the range of COT1, and the time length between T1 and T2 is the time length of COT1.

[0291] Step 1104: Determine that an avoidance condition is met.

[0292] In addition to A, B, C, and D in step 502, the avoidance conditions in this step further include: the amount of remaining available channels of UE1 is less than or equal to a threshold T th The amount of remaining available channels may be the amount of channels occupied by UE1 other than the channel in which the resource reserved by UE2 is located, and the threshold T' th may be determined by the total amount of channels occupied by UE1. For example, as shown in FIG. 12, UE1 preempts three channels, channel #1, channel #2, and channel #3. The resources reserved by UE2 are on channel #1, and the threshold T' this 1, and the amount of remaining available channels for UE1 is 2, which is assumed to be greater than the threshold. In this case, UE1 may avoid channel #1 for UE2 to transmit data, and channel #2 and channel #3 may be used by UE1 to transmit data.

[0293] Optionally, UE1 may perform resource re-evaluation or preemption detection. For details, please refer to the description of step 502. The details will not be described again.

[0294] Step 1105: UE1 transmits data on channel #2 and channel #3.

[0295] Specifically, as shown in FIG. 12, UE1 transmits data on channel #2 and channel #3 on time-frequency resources within the range of COT2, and the time length between T3 and T4 is the time length of COT2.

[0296] Step 1106: UE2 transmits data on channel #1.

[0297] Specifically, UE2 transmits data on channel #1 on time-frequency resources within COT1.

[0298] In this method, UE1 preempts multiple channels, and when the resource reserved by UE2 is on one of the multiple channels preempted by UE1, UE1 can avoid that channel and transmit data on another available channel, which is used by UE2 to transmit data, and the data of UE2 can be transmitted in a timely manner, which meets the service requirements and improves communication efficiency.

[0299] The embodiments described herein may be independent solutions or may be combined based on internal logic. All these solutions fall within the protection scope of this application. It should be understood that the steps of the above embodiments are only intended to clearly describe the technical solutions of the embodiments, and the order of performing the steps is not limited.

[0300] In the above-mentioned embodiments provided in the present application, the methods provided in the embodiments of the present application are described in terms of interactions between devices. In order to implement the functions of the methods provided in the above-mentioned embodiments of the present application, the network device or the terminal device may include a hardware structure and / or a software module, and may implement the above-mentioned functions in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module. Whether the functions in the above-mentioned functions are implemented using a hardware structure, a software module, or a combination of a hardware structure and a software module depends on the design constraints of a specific application and technical solution.

[0301] In the embodiment of the present application, the division into modules is an example and is merely a logical division of functions. In actual implementation, other division methods may be used. In addition, the functional modules in the embodiment of the present application may be integrated into one processor, may exist physically alone, or two or more modules may be integrated into one module. The integrated module may be implemented in the form of hardware, or may be implemented in the form of a software functional module.

[0302] The following describes in detail the communication device provided in the embodiment of the present application with reference to Figures 13 and 14. It should be understood that the description of the device embodiment corresponds to the description of the method embodiment. Therefore, for the contents that are not described in detail, please refer to the method embodiment. For the sake of brevity, the details will not be described again in this specification.

[0303] Similar to the above idea, as shown in FIG. 13, an embodiment of the present application further provides an apparatus 1300 configured to implement the function of the session management function network element in the above method. For example, the apparatus may be a software module or a chip system. In this embodiment of the present application, the chip system may include a chip, or may include a chip and another discrete component. The apparatus 1300 may include a processing unit 1310 and a communication unit 1320.

[0304] In this embodiment of the application, the communication unit may also be referred to as a transceiver unit and may include a transmitting unit and / or a receiving unit, which are respectively configured to perform the transmitting and receiving steps by the session management function network element in the aforementioned method embodiments.

[0305] The communication unit may also be referred to as a transceiver, a transceiver device, a transceiver apparatus, etc. The processing unit may also be referred to as a processor, a processing board, a processing module, a processing device, etc. Optionally, a component in the communication unit 1320 configured to implement a receiving function may be considered as a receiving unit, and a component in the communication unit 1320 configured to implement a transmitting function may be considered as a transmitting unit. In other words, the communication unit 1320 includes a receiving unit and a transmitting unit. The communication unit may also be sometimes referred to as a transceiver device, a transceiver, an interface circuit, etc. The receiving unit may also be sometimes referred to as a receiver device, a receiver, a receiving circuit, etc. The transmitting unit may also be sometimes referred to as a transmitter device, a transmitter, a transmitting circuit, etc.

[0306] When the communication device 1300 performs the function of the first terminal device in the procedure shown in any one of FIG. 5 to FIG. 11 in the above-mentioned embodiment, The communication unit may be configured to receive sidelink control information and transmit data, The processing unit may be configured to parse the sidelink control information, determine a transmission resource, determine a first channel occupancy state, determine whether an avoidance condition is met, and / or perform an LBT process, etc.

[0307] When the communication device 1300 performs the function of the second terminal device in the procedure shown in any one of FIG. 5 to FIG. 12 in the above-mentioned embodiment, The communication unit may be configured to transmit sidelink control information, receive second indication information, and / or transmit data; The processing unit may be configured to determine a transmission resource, perform LBT processing, and the like.

[0308] The above is merely an example. The processing unit 1310 and the communication unit 1320 may further perform other functions. For more detailed description, please refer to the related description in the method embodiment shown in Figure 5 to Figure 12 or other method embodiments. Details will not be described again in this specification.

[0309] Fig. 14 shows an apparatus 1400 according to an embodiment of the present application, which may be a hardware circuit implementation. The communication apparatus is applicable to the above-mentioned flow chart and implements the functions of the terminal device or the network device in the above-mentioned method embodiment. For ease of explanation, Fig. 14 shows only the main components of the communication apparatus.

[0310] The communication device 1400 may be a terminal device and can implement the functions of the first terminal device or the second terminal device in the method provided in the embodiment of the present application. Alternatively, the communication device 1400 may be a device that can support the first terminal device or the second terminal device in implementing the corresponding functions in the method provided in the embodiment of the present application. The communication device 1400 may be a chip system. In this embodiment of the present application, the chip system may include a chip, or may include a chip and another discrete component. For specific functions, please refer to the description in the preceding method embodiment.

[0311] The communication device 1400 includes one or more processors 1410 configured to implement or support the communication device 1400 in implementing the functions of the first terminal device or the second terminal device in the method provided in the embodiment of the present application. For details, please refer to the detailed description in the method example. Details will not be described again in this specification. The processor 1410 may also be called a processing unit or a processing module, and may implement a specific control function. The processor 1410 may be a general-purpose processor or a special-purpose processor. For example, the device includes a central processing unit, an application processor, a modem processor, a graphics processing unit, an image signal processor, a digital signal processor, a video codec processor, a controller, a memory, and / or a neural network processor. The central processing unit may be configured to control the communication device 1400, execute a software program, and / or process data. The different processors may be independent components or may be integrated into one or more processors, for example, integrated into one or more application specific integrated circuits. It may be understood that the processor in this embodiment of the application may be a central processing unit (CPU), or may be another general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a transistor logic device, a hardware component, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0312] Optionally, the communication device 1400 includes one or more memories 1420 configured to store instructions 1440. The instructions may be executed on the processor 1410 to enable the communication device 1400 to perform the methods described in the above method embodiments. The memory 1420 is coupled to the processor 1410. The coupling in this embodiment of the application may be an indirect coupling, or an electrical, mechanical, or other form of communication connection between devices, units, or modules, and is used for information exchange between devices, units, or modules. The processor 1410 may cooperate with the memory 1420. At least one of the at least one memory may be included in the processor. It should be noted that the memory 1420 is not required. Thus, the memory 1420 is illustrated by using a dashed line in FIG. 14.

[0313] Optionally, the memory 1420 may further store data. The processor and the memory may be disposed separately or integrated together. In this embodiment of the application, the memory 1420 may be a non-volatile memory, for example, a hard disk drive (HDD) or a solid-state drive (SSD), or a volatile memory, for example, a random access memory (RAM). Alternatively, the memory in this embodiment of the application may be a flash memory, a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a register, a hard disk, a removable hard disk, a CD-ROM, or any other form of storage medium well known in the art. For example, a storage medium is coupled to the processor, and the processor can read information from and write information to the storage medium. Of course, the storage medium may be components of the processor. The processor and the storage medium may reside in an ASIC. In addition, the ASIC may reside in a network device or terminal device. Of course, the processor and the storage medium may alternatively reside as discrete components in a network device or terminal device.

[0314] A memory is any medium capable of carrying or storing expected program code in the form of instructions or data structures, but is not limited thereto, and capable of being accessed by a computer. The memory in this embodiment of the present application may alternatively be a circuit or any other device capable of implementing a storage function and configured to store program instructions and / or data.

[0315] Optionally, the communication device 1400 may include instructions 1430 (sometimes also referred to as code or programs) that may be executed on the processor to enable the communication device 1400 to perform the methods described in the above embodiments. The processor 1410 may store data.

[0316] Optionally, the communications system 1400 may further include a transceiver 1450 and an antenna 1406. The transceiver 1450, which may also be referred to as a transceiver unit, transceiver module, transceiver device, transceiver circuit, transceiver, input / output interface, etc., is configured to implement receiving and transmitting functions of the communications device 1400 via the antenna 1406.

[0317] The processor 1410 and transceiver 1450 described in this application may be implemented in an integrated circuit (IC), an analog IC, a radio frequency identification (RFID), a mixed signal IC, an ASIC, a printed circuit board (PCB), an electronic device, etc. The communication device described herein may be an independent device (e.g., an independent integrated circuit or a mobile phone) or may be part of a larger device (e.g., a module that may be incorporated in another device). For details, please refer to the above description of the terminal device and the network device. Details will not be described again in this specification.

[0318] Optionally, the communication device 1400 may further include one or more of the following components: a wireless communication module, an audio module, an external memory interface, an internal memory, a universal serial bus (USB) interface, a power management module, an antenna, a speaker, a microphone, an input / output module, a sensor module, a motor, a camera, a display, etc. It may be understood that in some embodiments, the communication device 1400 may include more or fewer components, some components being integrated, or some components being split. These components may be implemented by hardware, software, or a combination of software and hardware.

[0319] It should be understood by those skilled in the art that the embodiments of the present application may be provided as a method, a system, or a computer program product. Thus, the present application may use the form of a hardware-only embodiment, a software-only embodiment, or an embodiment with a combination of software and hardware. Moreover, the present application may use the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk memory, optical memory, etc.) that contain computer-usable program code.

[0320] The present application is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the present application. It should be understood that computer program instructions can be used to implement each process and / or each block in the flowcharts and / or block diagrams, and combinations of processes and / or blocks in the flowcharts and / or block diagrams. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or any other programmable processing device to create a machine, and the instructions executed by the computer or processor of any other programmable data processing device create an apparatus for implementing a particular function in one or more processes in the flowcharts and / or in one or more blocks in the block diagrams.

[0321] These computer program instructions may be stored in a computer readable memory that can instruct a computer or any other programmable data processing device to act in a particular manner, and the instructions stored in the computer readable memory generate an artifact that includes an instruction apparatus that implements a particular function within one or more processes in the flowcharts and / or within one or more blocks in the block diagrams.

[0322] It is obvious that a person skilled in the art can make various modifications and variations to this application without departing from the scope of this application. This application is intended to cover these modifications and variations of this application, provided that they fall within the scope of protection defined by the following claims and equivalent technologies.

[0323] The above description is merely a specific implementation of the present invention, and is not intended to limit the scope of protection of the present application. Any modifications or replacements that are easily conceived by those skilled in the art within the technical scope disclosed in this application shall fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be subject to the scope of protection of the claims.

Claims

1. 1. A communication method comprising: receiving first indication information from a second terminal device, the first indication information indicating a first resource, the first resource being a resource reserved by the second terminal device for transmitting first data, and a resource corresponding to the first resource in a frequency domain belonging to a first channel; determining a second resource based on the first display information; transmitting second data on the second resource, a start time unit of the second resource being later than an end time unit of the first resource, and a resource corresponding to the second resource in a frequency domain belonging to the first channel; A communication method including:

2. The method comprises: sensing a state of the first channel being idle at a first sensing time unit by using a listen-before-talk process and suspending the listen-before-talk process at the first sensing time unit based on the first resource, the first sensing time unit being earlier than a start time unit of the first resource; The method of claim 1 further comprising:

3. The step of suspending the listen-before-talk process at the first sensing time unit based on the first resource includes: suspending the listen-before-talk process at the first sensing time unit when determining that a period between the start time unit and the first sensing time unit of the first resource is less than or equal to a first threshold, the first threshold being greater than 0 and less than or equal to a delay requirement of the second data. The method according to claim 1 or 2, comprising:

4. The step of suspending the listen-before-talk process at the first sensing time unit based on the first resource comprises: after gradually decreasing the value of the counter from Q to M, interrupting said gradually decreasing, where 1<M<Q, and Q is an initial value of said counter; The method according to claim 2 or 3, comprising:

5. The method comprises: sensing a state of the first channel to be idle in a second sensing time unit and continuing to progressively reduce the value of the counter from M, the second sensing time unit being later than the end time unit of the first resource and the start time unit of the second resource being the time unit at which the value of the counter is progressively reduced to 0; The method of claim 4 further comprising:

6. The method comprises: receiving a first reference signal from the second terminal device; determining that a power for receiving the first reference signal is greater than or equal to a reference signal receive power threshold; The method of any one of claims 1 to 5, further comprising:

7. The method comprises: receiving third display information from the second terminal device, the third display information indicating a destination to which the second terminal device transmits data; The method of any one of claims 1 to 6, further comprising:

8. The method comprises: receiving fourth display information from the second terminal device, the fourth display information indicating a priority of the first data; determining that the priority of the first data is greater than or equal to a priority of the second data; The method of any one of claims 1 to 7, further comprising:

9. 1. A communication method comprising: receiving first indication information from a second terminal device, the first indication information indicating a first resource, the first resource being a resource reserved by the second terminal device for transmitting second data; determining a third resource based on the first resource and a first channel occupation time, the third resource belonging to the first resource and the first channel occupation time, the third resource being used by the second terminal device to transmit first data, and a start time unit of the first channel occupation time being earlier than a start time unit of the first resource; transmitting the second data on a fourth resource, the fourth resource belonging to a resource other than the third resource within the first channel occupancy time; A communication method including:

10. The method comprises: transmitting second display information to the second terminal device, the second display information indicating the third resource; The method of claim 9 further comprising:

11. The step of transmitting second display information to the second terminal device includes: transmitting the second display information to the second terminal device within a first time period, wherein a start instant of the first time period falls within a range between a start time unit of the fourth resource and a start time unit of the third resource, and a duration between the start instant of the first time period and the start time unit of the fourth resource is equal to or greater than a second threshold value; 11. The method of claim 10, comprising:

12. The method comprises: receiving third display information from the second terminal device, the third display information indicating a destination to which the second terminal device transmits data; 12. The method of any one of claims 9 to 11, further comprising:

13. The method comprises: receiving a first reference signal from the second terminal device; determining that a power for receiving the first reference signal is greater than or equal to a reference signal receive power threshold; 13. The method of any one of claims 9 to 12, further comprising:

14. The method comprises: receiving fourth display information from the second terminal device, the fourth display information indicating a priority of the first data; determining that the priority of the first data is greater than or equal to a priority of the second data; 14. The method of any one of claims 9 to 13, further comprising:

15. 15. The method according to claim 9, wherein the first indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

16. 1. A communication method comprising: transmitting first indication information, the first indication information indicating a first resource, the first resource being a resource reserved by the second terminal device for transmitting first data; transmitting the first data on a third resource, the third resource being determined based on the first resource and a first channel occupation time, a start time unit of the first channel occupation time being earlier than a start time unit of the first resource, and the third resource belonging to the first resource and the first channel occupation time; A communication method including:

17. The method comprises: receiving second indication information from a first terminal device, the second indication information indicating the third resource; 20. The method of claim 16 further comprising:

18. The step of receiving second display information from the first terminal device includes: receiving the second display information from the first terminal device within a first time period; Including, 18. The method of claim 17, wherein a start instant of the first time period falls within a range between a start time unit of a fourth resource and a start time unit of the third resource, and a period between the start instant of the first time period and the start time unit of the fourth resource is greater than or equal to a second threshold.

19. The method comprises: transmitting third indication information, the third indication information indicating that the first terminal device is a destination to which the first data is to be transmitted; 19. The method of any one of claims 16 to 18, further comprising:

20. The method comprises: transmitting fourth indication information, the fourth indication information indicating a priority for transmitting the first data; 20. The method of any one of claims 16 to 19, further comprising:

21. The method comprises: Transmitting a first reference signal 21. The method of any one of claims 16 to 20, further comprising:

22. 22. The method according to any one of claims 16 to 21, wherein the first indication information is carried in at least one of first stage sidelink control information, second stage sidelink control information, a sidelink medium access control control element, or PC5 radio resource control signaling from the second terminal device.

23. A communication device comprising a module adapted to carry out a method according to any one of claims 1 to 8 or claims 9 to 15.

24. A communication device comprising a module adapted to carry out a method according to any one of claims 16 to 22.

25. A communication system comprising a communication device according to claim 23 and a communication device according to claim 24.

26. 23. A computer readable storage medium, the computer readable storage medium being configured to store a computer program, the computer program being enabled, when executed on a computer, to perform the method according to any one of claims 1 to 8, the method according to any one of claims 9 to 15, and / or the method according to any one of claims 16 to 22.

27. 23. An apparatus comprising a processor and a communications interface, the processor configured to read instructions and to perform a method according to any one of claims 1 to 8, a method according to any one of claims 9 to 15, and / or a method according to any one of claims 16 to 22.

28. 30. The device of claim 27, wherein the device is a chip.

Images