Device-to-Device Based Resource Determination Method and Device

Abstract

The embodiment of the present application provides a device - to - device based resource determination method and device, which can be applied to D2D systems (such as vehicle - to - everything, V2X, V2V, etc. systems). The method includes: receiving first information sent by a first terminal device, where the first information is used to instruct a second terminal device to send auxiliary information; sending the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in resource selection for data transmission. The second terminal device assists the first terminal device in determining the resources for data transmission, rather than the terminal device sending data completely determining the resources for data transmission by itself; this can avoid different terminal devices using the same resource to send data, avoid signal collisions and mutual interference during the data transmission process, and enable the data transmission of different terminal devices to be successful; for the case of resource reuse, it can make the resources be reasonably utilized and improve the resource utilization efficiency.

Description

Technical Field

[0001] This application relates to the field of communication technologies, and in particular, to a method and device for determining resources based on device-to-device (D2D). Background Art

[0002] With the development of communication technologies, device-to-device (D2D) technology has been applied and developed. D2D technology can reduce the burden on cellular networks, reduce the battery power consumption of user equipment, and increase data rates.

[0003] In the prior art, in D2D technology, a terminal device can obtain resources through sensing, and then send data to another terminal device by using the obtained resources.

[0004] However, in the prior art, different terminal devices determine resources respectively to use the resources for data transmission; that is, a terminal device determines resources by itself, and then the terminal device uses the resources determined by itself to send data to another terminal device; as a result, the terminal device cannot determine whether the resources are used by other terminal devices, and thus the used resources may have been occupied, or the resources may not be reasonably utilized. Summary of the Invention

[0005] Embodiments of this application provide a method and device for determining resources based on device-to-device, which can be applied in D2D technology, such as communication between terminal devices, or can be applied to vehicle networking, such as vehicle-to-everything (V2X) communication, long term evolution-vehicle (LTE-V), vehicle-to-vehicle (V2V) communication, etc., or can be used in fields such as intelligent driving and intelligent connected vehicles.

[0006] It should be understood that the method in the embodiments of the present application can be executed by a communication device, which can be the entire computing device or a part of the components in the computing device, such as chips related to wireless communication functions, such as system chips and communication chips. Among them, the system chip is also called a system-on-chip, or an SoC (System-on-a-Chip) chip. Specifically, the communication device can be a terminal such as a smart phone, or a system chip or a communication chip that can be set in the terminal. The communication chip can include one or more of a radio frequency processing chip and a baseband processing chip. The baseband processing chip is sometimes also called a modem or a baseband processor. In a physical implementation, the communication chip can be integrated inside the SoC chip or not integrated with the SoC chip. For example, the baseband processing chip is integrated in the SoC chip, and the radio frequency processing chip is not integrated with the SoC chip.

[0007] In a first aspect, the present application provides a method for determining resources based on device-to-device, the method comprising:

[0008] receiving first information sent by a first terminal device, where the first information is used to instruct a second terminal device to send auxiliary information;

[0009] sending the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0010] Through the above process, when the first terminal device needs to send data, the second terminal device assists the first terminal device in determining the resources for data transmission, that is, other terminal devices (the terminal device receiving the data, or a terminal device that is not the data receiving device) assist the first terminal device in determining the resources for data transmission, rather than the terminal device sending the data completely determining the resources for data transmission by itself; it is possible to avoid different terminal devices using the same resource to send data, avoid signal collisions and mutual interference during the data transmission process, and ensure the successful data transmission of different terminal devices; and, for the case of resource reuse, the resources can be reasonably utilized and the resource utilization efficiency can be improved.

[0011] In a second aspect, the present application provides a method for determining resources based on device-to-device, the method comprising:

[0012] sending first information to a second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information;

[0013] receiving the auxiliary information sent by the second terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission;

[0014] Determine the resources for data transmission according to the auxiliary information.

[0015] Through the above process, when the first terminal device needs to send data, the second terminal device assists the first terminal device in determining the resources for data transmission, that is, other terminal devices (the terminal device that receives data or the terminal device that is not the data-receiving terminal device) assist the first terminal device in determining the resources for data transmission, rather than the terminal device that sends data completely determining the resources for data transmission by itself; this can avoid different terminal devices using the same resource to send data, avoid signal collisions and mutual interference during the data transmission process, and enable the data transmission of different terminal devices to be successful; and, for the case of resource reuse, it can make the resources be reasonably utilized and improve the resource utilization efficiency.

[0016] In a third aspect, the present application provides a device-to-device based resource determination method, and the method includes:

[0017] Determine the resources for data transmission;

[0018] Send scheduling information to the first terminal device, where the scheduling information is used to indicate the resources for the first terminal device to transmit data.

[0019] Through the above process, when the first terminal device needs to send data, the second terminal device schedules resources for the first terminal device, that is, other terminal devices (the terminal device that receives data or the terminal device that is not the data-receiving terminal device) schedule the resources for the first terminal device to transmit data, rather than the terminal device that sends data completely determining the resources for data transmission by itself; the resources indicated by the second terminal device can directly exclude the resources occupied by other hidden terminals, can avoid different terminal devices using the same resource to send data, avoid signal collisions and mutual interference during the data transmission process, and enable the data transmission of different terminal devices to be successful; and, for the case of resource reuse, it can make the resources be reasonably utilized and improve the resource utilization efficiency.

[0020] In a fourth aspect, the present application provides a device-to-device based resource determination method, and the method includes:

[0021] Receive the scheduling information sent by the second terminal device, where the scheduling information is used to indicate the resources for the first terminal device to transmit data;

[0022] Send data according to the resources for data transmission.

[0023] Through the above process, when the first terminal device needs to send data, the second terminal device schedules resources for the first terminal device, that is, other terminal devices (the terminal device that receives the data or the terminal device that does not receive the data) schedule resources for the first terminal device to transmit data, rather than the terminal device that sends the data completely determining the resources for transmitting data by itself; the resources indicated by the second terminal device can directly exclude the resources occupied by other hidden terminals, which can avoid different terminal devices using the same resource to send data, avoid signal collisions and mutual interference during the data transmission process, and enable the data transmission of different terminal devices to be successful; and for the case of resource reuse, the resources can be reasonably utilized and the resource utilization efficiency can be improved.

[0024] In a fifth aspect, the present application provides a communication device, where the communication device includes:

[0025] A receiving unit, configured to receive first information sent by a first terminal device, where the first information is used to instruct the second terminal device to send auxiliary information;

[0026] A sending unit, configured to send the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0027] In a sixth aspect, the present application provides a communication device, where the communication device includes:

[0028] A sending unit, configured to send first information to a second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information;

[0029] A receiving unit, configured to receive the auxiliary information sent by the second terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission;

[0030] A processing unit, configured to determine resources for data transmission according to the auxiliary information.

[0031] In a seventh aspect, the present application provides a communication device, where the communication device includes:

[0032] A processing unit, configured to determine resources for data transmission;

[0033] A sending unit, configured to send scheduling information to a first terminal device, where the scheduling information is used to instruct the resources for data transmission of the first terminal device.

[0034] In an eighth aspect, the present application provides a communication device, where the communication device includes:

[0035] A receiving unit, configured to receive scheduling information sent by a second terminal device, where the scheduling information is used to indicate resources for a first terminal device to perform data transmission;

[0036] A sending unit, configured to send data according to the resources for performing data transmission.

[0037] In a ninth aspect, the present application provides a communication device, which includes a processor and a memory. A computer program is stored in the memory, and the processor executes the computer program stored in the memory, so that the device executes the method according to the first aspect and any possible method in the first aspect, or executes the method according to the second aspect and any possible method in the second aspect, or executes the method according to the third aspect and any possible method in the third aspect, or executes the method according to the fourth aspect and any possible method in the fourth aspect.

[0038] In a tenth aspect, the present application provides a communication device, including: a processor and an interface circuit;

[0039] The interface circuit is configured to receive a code instruction and transmit it to the processor;

[0040] The processor is configured to run the code instruction to execute the method according to the first aspect and any possible method in the first aspect, or execute the method according to the second aspect and any possible method in the second aspect, or execute the method according to the third aspect and any possible method in the third aspect, or execute the method according to the fourth aspect and any possible method in the fourth aspect.

[0041] In an eleventh aspect, the present application provides a readable storage medium, which stores instructions. When the instructions are executed, the method according to the first aspect and any possible method in the first aspect, or the method according to the second aspect and any possible method in the second aspect, or the method according to the third aspect and any possible method in the third aspect, or the method according to the fourth aspect and any possible method in the fourth aspect is implemented.

[0042] In a twelfth aspect, the present application provides a computer program product. When the program code included in the computer program product is executed by a processor in a terminal, the method according to the first aspect and any possible method in the first aspect, or the method according to the second aspect and any possible method in the second aspect, or the method according to the third aspect and any possible method in the third aspect, or the method according to the fourth aspect and any possible method in the fourth aspect is implemented.

[0043] In a thirteenth aspect, the present application provides a processor, which is used to execute any possible method in the first aspect and the first aspect, or execute any possible method in the second aspect and the second aspect, or execute any possible method in the third aspect and the third aspect, or execute any possible method in the fourth aspect and the fourth aspect.

[0044] In a fourteenth aspect, the present application provides a chip applied to a terminal device, which is used to execute and implement any possible method in the first aspect and the first aspect, or any possible method in the second aspect and the second aspect, or any possible method in the third aspect and the third aspect, or execute and implement any possible method in the fourth aspect and the fourth aspect.

[0045] In a fifteenth aspect, the present application provides a communication system, which includes any possible communication device in the fifth aspect and the fifth aspect, and any possible communication device in the sixth aspect and the sixth aspect; or, the communication system includes any possible communication device in the seventh aspect and the seventh aspect, and any possible communication device in the eighth aspect and the eighth aspect.

[0046] It should be understood that the technical solution details and technical effects involved in any possible implementation manner from the fifth aspect to the fifteenth aspect or any aspect can refer to the technical aspect details and technical effects described in any possible implementation manner of the first aspect or the first aspect, or refer to the technical aspect details and technical effects described in any possible implementation manner of the second aspect or the second aspect, or refer to the technical aspect details and technical effects described in any possible implementation manner of the third aspect or the third aspect, or refer to the technical aspect details and technical effects described in any possible implementation manner of the fourth aspect or the fourth aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a schematic structural diagram of a communication system provided by an embodiment of the present application;

[0048] Figure 2 It is a schematic structural diagram of another communication system provided by an embodiment of the present application;

[0049] Figure 3 It is a schematic diagram of an application scenario provided by an embodiment of the present application;

[0050] Figure 4 It is a schematic diagram of another application scenario provided by an embodiment of the present application;

[0051] Figure 5 It is a schematic diagram of another application scenario provided by an embodiment of the present application;

[0052] Figure 6 Schematic diagram of another application scenario provided by the embodiment of the present application;

[0053] Figure 7 Schematic diagram of the structure of another communication system provided by the embodiment of the present application;

[0054] Figure 8 Schematic diagram of the structure of another communication system provided by the embodiment of the present application;

[0055] Figure 9 Schematic diagram of the process of a device-to-device based resource determination method provided by the embodiment of the present application;

[0056] Figure 10 Schematic diagram of the candidate resource set provided by the embodiment of the present application;

[0057] Figure 11 Schematic diagram of the resource selection process for listening provided by the embodiment of the present application;

[0058] Figure 12 Signaling diagram of a device-to-device based resource determination method provided by the embodiment of the present application;

[0059] Figure 13 Signaling diagram of another device-to-device based resource determination method provided by the embodiment of the present application;

[0060] Figure 14 Signaling diagram of another device-to-device based resource determination method provided by the embodiment of the present application;

[0061] Figure 15 Signaling diagram of another device-to-device based resource determination method provided by the embodiment of the present application;

[0062] Figure 16 Signaling diagram of another device-to-device based resource determination method provided by the embodiment of the present application;

[0063] Figure 17 Signaling diagram of another device-to-device based resource determination method provided by the embodiment of the present application;

[0064] Figure 18 Signaling diagram of another device-to-device based resource determination method provided by the embodiment of the present application;

[0065] Figure 19 Signaling diagram of another device-to-device based resource determination method provided by the embodiment of the present application;

[0066] Figure 20 Signaling diagram of another device-to-device based resource determination method provided by the embodiment of the present application;

[0067] Figure 21 It is a schematic flowchart of another device-to-device based resource determination method provided by an embodiment of the present application;

[0068] Figure 22 It is a schematic flowchart of another device-to-device based resource determination method provided by an embodiment of the present application;

[0069] Figure 23 It is a signaling diagram of another device-to-device based resource determination method provided by an embodiment of the present application;

[0070] Figure 24 It is a signaling diagram of another device-to-device based resource determination method provided by an embodiment of the present application;

[0071] Figure 25 It is a signaling diagram of another device-to-device based resource determination method provided by an embodiment of the present application;

[0072] Figure 26 It is a signaling diagram of another device-to-device based resource determination method provided by an embodiment of the present application;

[0073] Figure 27 It is a signaling diagram of another device-to-device based resource determination method provided by an embodiment of the present application;

[0074] Figure 28 It is a signaling diagram of another device-to-device based resource determination method provided by an embodiment of the present application;

[0075] Figure 29 It is a signaling diagram of another device-to-device based resource determination method provided by an embodiment of the present application;

[0076] Figure 30 It is a schematic flowchart of another device-to-device based resource determination method provided by an embodiment of the present application;

[0077] Figure 31 It is a schematic structural diagram of a communication device provided by an embodiment of the present application;

[0078] Figure 32 It is a schematic structural diagram of another communication device provided by an embodiment of the present application;

[0079] Figure 33 It is a schematic structural diagram of another communication device provided by an embodiment of the present application;

[0080] Figure 34 It is a schematic structural diagram of another communication device provided by an embodiment of the present application;

[0081] Figure 35Schematic structural diagram of another communication device provided by an embodiment of the present application;

[0082] Figure 36 Schematic structural diagram of another communication device provided by an embodiment of the present application;

[0083] Figure 37 Schematic structural diagram of another communication device provided by an embodiment of the present application;

[0084] Figure 38 Schematic structural diagram of another communication device provided by an embodiment of the present application. Detailed implementation manners

[0085] The following combines the accompanying drawings and gives embodiments to further illustrate the technical solutions provided by the present application. It should be understood that the system structures and application scenarios provided in the embodiments of the present application are mainly used to illustrate possible implementation manners of the technical solutions of the present application, and should not be interpreted as the only limitation of the technical solutions of the present application. Those of ordinary skill in the art know that with the evolution of the system structure and the emergence of new service scenarios, the technical solutions provided by the present application are also applicable to similar technical problems.

[0086] It should be understood that the embodiments of the present application provide a method and device for resource determination based on device-to-device, so that the terminal device can determine whether the resource is utilized by other terminal devices, ensuring the reasonable utilization of the resource.

[0087] Since the principles of these technical solutions for solving problems are the same or similar, in the following introduction of specific embodiments, some repetitions may not be elaborated again, but it should be regarded that there are mutual references between these specific embodiments and they can be combined with each other.

[0088] Embodiments of the present application are applied to a fifth-generation mobile communication network (5th-generation, 5G) communication system or other systems that may emerge in the future, and can also be applied to other communication systems, such as: wireless local area network (WLAN) systems, global system of mobile communication (GSM) systems, code division multiple access (CDMA) systems, wideband code division multiple access (WCDMA) systems, general packet radio service (GPRS), long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication systems, and so on.

[0089] The following explains some terms in the present application to facilitate understanding by those skilled in the art. It should be noted that when the solutions of the embodiments of the present application are applied to 5G systems, or existing systems, or other systems that may emerge in the future, the names of network devices and terminal devices may change, but this does not affect the implementation of the solutions of the embodiments of the present application.

[0090] 1) A terminal device is a device with wireless transceiver functions. The terminal device can be deployed on land, including indoors or outdoors, handheld, wearable or vehicle-mounted; it can also be deployed on water (such as ships, etc.); it can also be deployed in the air (such as airplanes, balloons, satellites, etc.).

[0091] The terminal device may specifically be, but is not limited to: mobile phone, mobile phone, tablet computer, laptop computer, computer with wireless transceiver function, virtual reality (VR) terminal device, augmented reality (AR) terminal device, wireless terminal in industrial control, vehicle-mounted terminal device, wireless terminal in self-driving, wireless terminal in remote medical, wireless terminal in smart grid, wireless terminal in transportation safety, wireless terminal in smart city, wireless terminal in smart home, wearable terminal device (smart watch, smart bracelet, smart helmet, smart glasses, etc.) and other communication devices with wireless access capability, such as various Internet of Things devices, including smart home devices (smart meters, smart appliances, etc.), smart vehicles, etc. The embodiments of the present application do not limit the application scenarios.

[0092] The terminal device may also be referred to as a terminal, user equipment (UE), mobile station (MS), or subscriber unit (SU), access terminal device, vehicle-mounted terminal, industrial control terminal, UE unit, UE station, mobile station, mobile platform, remote station, remote terminal device, mobile device, UE terminal device, terminal device, wireless communication device, UE agent, or UE device, etc. In the description of the embodiments of the present application, the terminal device and UE are not distinguished. The terminal device may also be fixed or mobile.

[0093] 2) The network device may be any device with wireless transceiver function.

[0094] The network device may specifically be, but is not limited to: an evolved base station (NodeB or eNB or e-NodeB, evolutional Node B) in LTE, a base station (gNodeB or gNB) or a transmission receiving point (TRP) in NR, a radio access network (RAN) device, a base station evolved from 3GPP later, an access node in a WiFi system, a wireless relay node, a wireless backhaul node, etc. The network device may also be a wireless controller, a centralized unit (CU), and / or a distributed unit (DU) in the scenario of a cloud radio access network (CRAN). The network device may also be a server, a wearable device, a vehicle-mounted device, etc.

[0095] Among them, the base station may be: a macro base station, a micro base station, a pico base station, a small station, a relay station, or a balloon station, etc. Multiple base stations may support the network of the same technology mentioned above, or may support the networks of different technologies mentioned above. The base station may include one or more co-site or non-co-site TRPs.

[0096] When there are multiple network devices, the multiple network devices may be of the same type of network device, or may be of different types of network devices. The network device may communicate with the terminal device, or may communicate with the terminal device through a relay station. The terminal device may communicate with multiple network devices of different technologies. For example, the terminal device may communicate with a network device supporting an LTE network, may also communicate with a network device supporting a 5G network, and may also support dual connection with a network device of an LTE network and a network device of a 5G network.

[0097] 3) "Multiple" means two or more, and other quantifiers are similar. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0098] 4) "Corresponding" may refer to an association relationship or a binding relationship. A corresponding to B means that there is an association relationship or a binding relationship between A and B.

[0099] It should be noted that the nouns or terms involved in the embodiments of the present application may refer to each other and will not be elaborated.

[0100] With the development of communication technologies, users' requirements for high data rates are increasing, and users have a need to communicate with neighboring devices. As a result, D2D technology has emerged and has been applied and developed. D2D technology can relieve the burden on cellular networks, reduce the battery power consumption of user equipment, and increase data rates. D2D technology allows multiple terminal devices supporting D2D functions to perform direct discovery and direct communication with or without network infrastructure.

[0101] Figure 1 This is a schematic structural diagram of a communication system provided by an embodiment of this application. As Figure 1 shown, in D2D technology, communication occurs between terminal device 01 and terminal device 02; among them, terminal device 01 can provide resources for data transmission to terminal device 02, or terminal device 02 can provide resources for data transmission to terminal device 01.

[0102] With the development of D2D technology and the new radio (NR) technology of 5G, 5G NR D2D will also further develop, and then support lower transmission delays, more reliable communication transmissions, higher throughput, and better user experiences to meet the requirements of a wider range of application scenarios.

[0103] For example, Figure 2 This is another schematic structural diagram of a communication system provided by an embodiment of this application. D2D technology can be applied to the Internet of Vehicles. Based on D2D technology, under the network of the long term evolution (LTE) technology proposed by the 3rd generation partnership project (3GPP), vehicle-to-everything (V2X) communication technology has been proposed. V2X communication technology refers to the communication between a vehicle and anything outside, including vehicle-to-vehicle (V2V), vehicle-to-pedestrian (V2P), vehicle-to-infrastructure (V2I), and vehicle-to-network (V2N). As Figure 2 shown in Figure (a) in the middle, it shows V2V; as Figure 2 shown in Figure (b) in the middle, it shows V2P; as Figure 2 shown in Figure (c) in the middle, it shows V2I or V2N.

[0104] Among them, V2X communication targets high-speed devices represented by vehicles; V2X communication under LTE can support communication scenarios with and without network coverage, and can adopt a network access device scheduling mode for resource allocation. The network access device scheduling mode is, for example, the evolved universal terrestrial radio access network node B (e-UTRAN node B, eNB) scheduling mode or the UE self-selection mode. Based on the V2X communication method, vehicle users (vehicle UE, V-UE) can send some of their own information to surrounding vehicle users and can receive information sent by surrounding vehicle users; the information is, for example, information such as position, speed, intention (turning, lane changing, reversing), etc.

[0105] V2X under LTE has solved some basic requirements in the V2X scenario, but for future application scenarios such as fully intelligent driving and autonomous driving, the current LTE V2X cannot effectively support them. With the development of the new radio (NR) technology of 5G, 5GNR V2X will also be further developed to support lower transmission delays, more reliable communication transmissions, higher throughput, and better user experiences to meet the needs of a wider range of application scenarios.

[0106] Figure 3 A schematic diagram of an application scenario provided by an embodiment of the present application is as Figure 3 shown, Figure 3 In the network architecture of the shown application scenario, there are terminal device A and terminal device B; terminal device A and terminal device B communicate with each other. Terminal device A is the data receiving end, and terminal device B is the data sending end.

[0107] Figure 4 Another schematic diagram of an application scenario provided by an embodiment of the present application is as Figure 4 shown, Figure 4 In the network architecture of the shown application scenario, there are terminal device A, terminal device B, and terminal device C; terminal device B and terminal device C communicate with each other. Terminal device C is the data receiving end, and terminal device B is the data sending end. Terminal device A is used to indicate resources, and the resources are used for data transmission and reception between terminal device B and terminal device C; that is, terminal device A has an assisting ability and can also have all or part of the scheduling ability. The resources indicated by terminal device A are used for communication between terminal device B and terminal device C.

[0108] Figure 5 Another schematic diagram of an application scenario provided by an embodiment of the present application is as Figure 5 shown, Figure 5In the network architecture of the application scenario shown, there are a terminal device A, a terminal device B, and a network device; the terminal device A communicates with the terminal device B, the terminal device A is the data receiving end, and the terminal device B is the data sending end. When the terminal device has all or part of the scheduling ability, the terminal device A listens for resources and performs scheduling processing using the listened resources; or, when the terminal device A has all or part of the scheduling ability, the network device configures resources for the terminal device A so that the terminal device A can perform scheduling processing using the resources.

[0109] Figure 6 As shown in the figure, it is a schematic diagram of another application scenario provided by the embodiments of the present application, such as Figure 6 shown Figure 6 In the network architecture of the application scenario shown, there are a terminal device A, a terminal device B, a terminal device C, and a network device; the terminal device C communicates with the terminal device B, the terminal device C is the data receiving end, and the terminal device B is the data sending end. When the terminal device has all or part of the scheduling ability, the terminal device A listens for resources and performs scheduling processing using the listened resources; or, when the terminal device A has all or part of the scheduling ability, the network device configures resources for the terminal device A so that the terminal device A can perform scheduling processing using the resources.

[0110] The above-mentioned "scheduling ability" refers to the ability to schedule resources. The communication interface between the terminal device and the network device can be a Uu (Uu interface, Uu) interface. The communication interface between terminal devices can be a PC5 (PC5 interface, PC5) interface.

[0111] In D2D technology, the terminal device needs to use resources for data transmission. Furthermore, the terminal device needs to obtain resources before data transmission. There are the following several ways for the terminal device to obtain resources.

[0112] The first way for the terminal device to obtain resources: is Mode 1; Mode 1 means that the network device schedules resources, and the resources are used for data transmission between terminal devices.

[0113] However, in the above first way, in D2D technology, since it is direct communication between terminal devices, when the terminal device cannot connect to the network device in time, the network device cannot schedule resources for the terminal device.

[0114] The second way for the terminal device to obtain resources: is Mode 2; Mode 2 means that without the network device scheduling resources, the terminal device determines the resources for data transmission within the resources configured by the network device or pre-configured.

[0115] Among them, in the above-mentioned second method, resources can be determined through processes such as listening, resource selection, and resource reselection. Listening refers to decoding sidelink control information (SCI) and / or sidelink (SL) measurements of other terminal devices. The processes of resource selection and resource reselection can use the results of listening, which are used to determine the resources for data transmission.

[0116] However, in the above-mentioned second method, different terminal devices determine resources respectively to transmit data using the resources; that is, a terminal device determines resources by itself, and then the terminal device uses the resources it determines to transmit data to another terminal device; as a result, the terminal device cannot determine whether the resources are being used by other terminal devices, and thus there may be a situation where the resources used have been occupied, or the resources are not utilized reasonably.

[0117] For example, Figure 7 is a schematic structural diagram of another communication system provided by an embodiment of the present application, as Figure 7 shown. Terminal device A, terminal device B, and terminal device C can all determine resources in the manner of the above-mentioned mode 2; Figure 7 The range delimited by the dashed line in is the listening range of terminal device C, Figure 7 The range delimited by the solid line in is the listening range of terminal device B; it can be seen that terminal device C is outside the listening range of terminal device B, and terminal device C is a hidden node of terminal device B; terminal device B is outside the listening range of terminal device C, and terminal device B is a hidden node of terminal device C.

[0118] Both terminal device B and terminal device C have data to send to terminal device A. Terminal device C selects resource 1 to send data to terminal device A according to mode 2. Since terminal device B is a hidden node of terminal device C, terminal device B does not know the existence of terminal device C, and terminal device B cannot detect that resource 1 has been occupied by terminal device C, and will consider resource 1 to be idle, and then use resource 1 to send data to terminal device A; at this time, since terminal device C and terminal device B use the same resource to send data, signal collision and mutual interference in the data transmission process will occur, resulting in the failure of data transmission of both terminal device C and terminal device B. Moreover, when there are more hidden nodes outside the listening range of terminal device B, the problems of signal collision and data transmission failure are more serious.

[0119] For example, Figure 8 is a schematic structural diagram of another communication system provided by an embodiment of the present application, as Figure 8 shown. Terminal device A, terminal device B, terminal device C, and terminal device D can all determine resources in the manner of the above-mentioned mode 2;Figure 8 The range delimited by the dashed line in [it] is the listening range of the terminal device C. Figure 8 The range delimited by the solid line in [it] is the listening range of the terminal device B.

[0120] The terminal device B has data to send to the terminal device A, and the terminal device C has data to send to the terminal device D. The terminal device C selects resource 1 according to mode 2 and uses resource 1 to send data to the terminal device D. The terminal device B can detect that this resource is occupied. To avoid signal collision, the terminal device B does not select resource 1 but selects other resources to send data to the terminal device A. However, for the case of resource reuse, actually the terminal device B can use this resource 1 to send data to the terminal device A, and the terminal device A will not receive the interference caused by the signal sent by the terminal device C on this resource 1; where resource reuse means that the terminal device uses the same time-frequency resource for data transmission. Therefore, the resources are not reasonably utilized and the resource utilization efficiency is not high; the terminal device needs to reselect resources, resulting in low communication efficiency.

[0121] It can be seen that in the above several communication methods, when the terminal device cannot connect to the network device in time, the network device cannot schedule resources for the terminal device; or, the terminal device cannot determine whether the resources are utilized by other terminal devices, and thus the utilized resources may have been occupied; or, the resources are not reasonably utilized and the resource utilization efficiency is not high. Thereby, it affects the communication process of the terminal device and the user experience.

[0122] Figure 9 As shown in the following, it is a schematic flowchart of a method for determining resources based on device-to-device provided by an embodiment of the present application. Figure 9 As shown, this method includes:

[0123] S101. Receive the first information sent by the first terminal device, where the first information is used to instruct the second terminal device to send auxiliary information.

[0124] In one example, the preset indication field or preset bit in the first information is used to instruct the second terminal device to send auxiliary information.

[0125] In one example, the first information is physical layer sidelink control information, or media access control (MAC) layer sidelink control information, or radio resource control (RRC) layer sidelink control information.

[0126] Exemplarily, the execution subject of the method provided in this embodiment may be the second terminal device. The second terminal device communicates with the first terminal device.

[0127] The first terminal device is the sender of data, the second terminal device is the receiver of data, and the second terminal device is the assisting device. Or, the first terminal device is the sender of data, the second terminal device is not the receiver of data, and the second terminal device is the assisting device.

[0128] Herein, the "assisting device" refers to a device that provides a resource or a set of resources for other terminal devices, and the resource or the set of resources is used for the selection of resources for data transmission by other terminal devices.

[0129] In this embodiment, since the second terminal device is the assisting device, the second terminal device provides a resource or a set of resources for the first terminal device; and, the resource or the set of resources is used for the selection of resources for data transmission by the first terminal device. For example, the resource or the set of resources is used for the first terminal device to select whether to be a resource for data transmission.

[0130] When the first terminal device needs to send data, the first terminal device sends a first message to the second terminal device. Herein, the first message is used to instruct the second terminal device to send assisting information, and the assisting information is used to assist the first terminal device in selecting resources for data transmission. In one example, the first message is used to instruct the first terminal device that it needs the second terminal device to return assisting information to the first terminal device, that is, in addition to instructing the second terminal device to send assisting information, the first message also indicates that it is the first terminal device that needs the assisting information.

[0131] In one example, the first terminal device sends a first message to the second terminal device. Herein, the first message is a separate signaling, and the first message has multiple indication fields. One preset indication field among the multiple indication fields can be used to instruct the second terminal device to send assisting information; the position of the preset indication field in the first message and the size of the preset indication field are not limited. Or, the first message is a separate signaling, and the first message has multiple bits. One preset bit among the multiple indication fields can be used to instruct the second terminal device to send assisting information; the position of the preset bit in the first message and the size of the preset bit are not limited.

[0132] In another example, the first message is a physical layer sidelink control information; a preset indication field in the physical layer sidelink control information is used to instruct the second terminal device to send assisting information, or a preset bit in the physical layer sidelink control information is used to instruct the second terminal device to send assisting information. Herein, the physical layer sidelink control information can instruct the second terminal device to send assisting information in an explicit manner, or the physical layer sidelink control information can instruct the second terminal device to send assisting information in an implicit manner. For example, the physical layer sidelink control information can be a first stage sidelink control information (1 ststage SCI), or, second-stage sidelink control information (2 nd stageSCI), or, sidelink control information (SCI).

[0133] For example, the first piece of information is 2 nd stage SCI, 2 nd stage SCI has a preset indication field; when the value in the preset indication field is the first value, it represents activating the second terminal device to send auxiliary information to the first terminal device; when the value in the preset indication field is the second value, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device, "deactivating" means that the second terminal device is not required to send auxiliary information, and the first value and the second value are different; and, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, that is, 2 nd stageSCI includes the identifier of the terminal device that sends 2 nd stage SCI, and the identifier of the terminal device that receives 2 nd stage SCI. At this time, the first piece of information indicates the second terminal device to send auxiliary information in an explicit manner. For example, the first terminal device sends 2 nd stage SCI, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; 2 nd stage SCI has a 1-bit indication field, and the 1-bit indication field is used to indicate whether the second terminal device sends auxiliary information; when the 1-bit indication field is 1, it means activating the second terminal device to send auxiliary information to the first terminal device, and when the 1-bit indication field is 0, it means deactivating the second terminal device from sending auxiliary information to the first terminal device.

[0134] For example, the first piece of information is 1 st stage SCI, 1 st stage SCI has a preset indication field; when the value in the preset indication field is the first value, it represents activating the second terminal device to send auxiliary information to the first terminal device; when the value in the preset indication field is the second value, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device, "deactivating" means that the second terminal device is not required to send auxiliary information, and the first value and the second value are different. And, the second terminal device receives 1 st stage SCI before or receives 1 stAfter stage SCI, the second terminal device also needs to receive the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device. For example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that requests auxiliary information from itself. At this time, the first information indicates the second terminal device to send auxiliary information in an explicit manner. For example, the first terminal device sends 1 to the second terminal device st stage SCI and 2 nd stage SCI; 1 st There is a 1-bit indication field in stage SCI. The 1-bit indication field is used to indicate whether the second terminal device sends auxiliary information. When the value in the 1-bit indication field is 1, it means to activate the second terminal device to send auxiliary information to the first terminal device. When the value in the 1-bit indication field is 0, it means to deactivate the second terminal device from sending auxiliary information to the first terminal device; 2 nd stage SCI is used to indicate the identification of the first terminal device and the identification of the second terminal device.

[0135] For example, the first information is 2 nd stage SCI; 2 nd There is a preset bit position in stage SCI; when the preset bit position is the first bit sequence, it represents activating the second terminal device to send auxiliary information to the first terminal device. The first bit sequence includes at least one bit position; when the preset bit position is the second bit sequence, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device. "Deactivating" means that the second terminal device does not need to send auxiliary information. The second bit sequence includes at least one bit position; the first bit sequence and the second bit sequence are different bit sequences. And, 2 nd stage SCI itself includes the identification of the first terminal device and the identification of the second terminal device, 2 nd stage SCI includes 2 nd the identification of the terminal device that sends stage SCI, and 2 nd the identification of the terminal device that receives stage SCI. At this time, the first information indicates the second terminal device to send auxiliary information in an implicit manner. For example, the first terminal device sends 2 to the second terminal device nd stage SCI, 2 nd stage SCI itself includes the identification of the first terminal device and the identification of the second terminal device; 2 nd There is a cyclic redundancy checksum (CRC) in stage SCI. At this time, 1-bit scrambling is used in 2nd at the last bit of the CRC of stage SCI; scrambling with 1 indicates activating the second terminal device to send auxiliary information to the first terminal device, and scrambling with 0 indicates deactivating the second terminal device from sending auxiliary information to the first terminal device. For example, 2 nd The CRC of stage SCI is a 24-bit bit sequence 0101 1010 0101 1010 0101 1010, and the CRC scrambled with 1 is 0101 1010 0101 1010 0101 1011, which indicates activating the second terminal device to send auxiliary information to the first terminal device at this time.

[0136] For example, the first information is 1 st stage SCI, 1 st There is a preset bit in stage SCI; when the preset bit is the first bit sequence, it represents activating the second terminal device to send auxiliary information to the first terminal device, and the first bit sequence includes at least one bit; when the preset bit is the second bit sequence, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device, and "deactivating" means that the second terminal device does not need to send auxiliary information, and the second bit sequence includes at least one bit; the first bit sequence and the second bit sequence are different bit sequences. Also, the second terminal device receives 1 st before receiving stage SCI or after receiving stage SCI st and also receives identification information sent by the first terminal device, and the identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that requests auxiliary information from itself. At this time, the first information implicitly indicates that the second terminal device sends auxiliary information. For example, the first terminal device sends 1 st stage SCI and 2 nd stage SCI; 1 st There is a CRC in stage SCI. At this time, 1-bit scrambling is performed on the last bit of the CRC of stage SCI st Scrambling with 1 indicates activating the second terminal device to send auxiliary information to the first terminal device, and scrambling with 0 indicates deactivating the second terminal device from sending auxiliary information to the first terminal device; 2 nd stage SCI is used to indicate the identification of the first terminal device and the identification of the second terminal device. For example, 1 stThe CRC of stage SCI is a 24-bit bit sequence 0101 1010 0101 1010 0101 1010. After scrambling with 1, the CRC is 0101 1010 0101 1010 0101 1011, which indicates to activate the second terminal device to send auxiliary information to the first terminal device at this time.

[0137] In another example, the first information is MAC layer sidelink control information; the preset indication field in the MAC layer sidelink control information is used to indicate that the second terminal device sends auxiliary information, or the preset bit in the MAC layer sidelink control information is used to indicate that the second terminal device sends auxiliary information. Among them, the MAC layer sidelink control information can indicate that the second terminal device sends auxiliary information in an explicit manner, or the MAC layer sidelink control information can indicate that the second terminal device sends auxiliary information in an implicit manner. For example, the MAC layer sidelink control information can be SL MAC CE information, where SL refers to Sidelink, MAC refers to media access control layer, and CE refers to control element.

[0138] For example, the first information is SL MAC CE information, and there is a preset indication field in the SL MAC CE information; when the value in the preset indication field is the first value, it represents activating the second terminal device to send auxiliary information to the first terminal device; when the value in the preset indication field is the second value, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device. "Deactivate" means that the second terminal device does not need to send auxiliary information, and the first value and the second value are different. Also, before or after the second terminal device receives the SL MAC CE information, it also needs to receive the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that requests auxiliary information from itself. At this time, the first information indicates that the second terminal device sends auxiliary information in an explicit manner. For example, the first terminal device sends SL MAC CE information and 2 nd stage SCI; there is a preset indication field in the SL MAC CE information, and the preset indication field is used to indicate whether the second terminal device sends auxiliary information; when the preset indication field is 1, it means to activate the second terminal device to send auxiliary information to the first terminal device, and when the preset indication field is 0, it means to deactivate the second terminal device from sending auxiliary information to the first terminal device; 2 ndThe stage SCI is used to indicate the identifier of the first terminal device and the identifier of the second terminal device.

[0139] In another example, the first information is RRC layer sidelink control information; a preset indication field in the RRC layer sidelink control information is used to indicate that the second terminal device sends auxiliary information, or a preset bit in the RRC layer sidelink control information is used to indicate that the second terminal device sends auxiliary information. Among them, the RRC layer sidelink control information can indicate that the second terminal device sends auxiliary information in an explicit manner, or the RRC layer sidelink control information can indicate that the second terminal device sends auxiliary information in an implicit manner. For example, the RRC layer sidelink control information can be PC5 RRC information.

[0140] For example, the first information is PC5 RRC information, and there is a preset indication field in the PC5 RRC information; when the value in the preset indication field is the first value, it represents activating the second terminal device to send auxiliary information to the first terminal device; when the value in the preset indication field is the second value, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device, and "deactivating" means that the second terminal device does not need to send auxiliary information, and the first value and the second value are different. Moreover, before or after the second terminal device receives the PC5 RRC information, it also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that requests auxiliary information from itself. At this time, the first information indicates that the second terminal device sends auxiliary information in an explicit manner. For example, the first terminal device sends PC5 RRC information and 2 nd stage SCI to the second terminal device; there is a preset indication field in the PC5 RRC information, and the preset indication field is used to indicate whether the second terminal device sends auxiliary information; the preset indication field can be indicated by an integer. When the preset indication field is 1, it means activating the second terminal device to send auxiliary information to the first terminal device. When the preset indication field is 0, it means deactivating the second terminal device from sending auxiliary information to the first terminal device; 2 nd stage SCI is used to indicate the identifier of the first terminal device and the identifier of the second terminal device. For another example, the first terminal device sends PC5 RRC information and 2 ndstage SCI; There is a preset indication field in the PC5 RRC information, and the preset indication field is used to indicate whether the second terminal device sends auxiliary information; the preset indication field can be indicated by an enumeration type, and the members of the enumeration type include activate and deactivate. When the preset indication field is activate, it means to activate the second terminal device to send auxiliary information to the first terminal device. When the preset indication field is deactivate, it means to deactivate the second terminal device to send auxiliary information to the first terminal device; 2 nd stage SCI is used to indicate the identifier of the first terminal device and the identifier of the second terminal device.

[0141] S102. Send auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in resource selection for data transmission.

[0142] In one example, the auxiliary information is specifically used to indicate the size and location anchor of the resource for data transmission.

[0143] In one example, the auxiliary information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

[0144] Exemplarily, after receiving the first information, the second terminal device determines the "resource for data transmission", and then generates auxiliary information.

[0145] In one example, the auxiliary information indicates the resource for data transmission; in order to facilitate the first terminal device to determine the location of the resource, the auxiliary information can indicate the size of the resource for data transmission and the location anchor of the resource for data transmission.

[0146] In one example, the second terminal device can obtain channel state information, and then determine the resource size required for the first terminal device to perform data transmission according to the channel state information; the second terminal device listens at the granularity of the resource size, and then listens to the unoccupied resource or the set of unoccupied resources. Thus, the second terminal device uses the listened unoccupied resource or resource set as the resource for data transmission. Among them, the granularity of the resource size can be a subchannel, or a resource block group (RBG), or a resource block (RB), etc.; there is no limitation on the granularity of the resource size.

[0147] Here, the process of "listening" to a resource or a set of resources is introduced. "Listening" refers to the above-mentioned Mode2 mode. When listening, when the terminal device needs to send data, the MAC layer of the terminal device instructs the physical layer of the terminal device to perform listening, and then determines a subset of resources. The MAC layer of the terminal device will select resources for transmitting data on the Physical Sidelink Share Channel (PSSCH) or the Physical Sidelink Control Channel (PSCCH) within this subset of resources. The terminal device determines the resource listening result within the resource listening window, and then selects a set of resources or resources within the resource selection window according to the resource listening result.

[0148] For example, assume that the terminal device triggers resource selection at time slot n. The above-mentioned "resource listening window" can be defined as the T time slots before the trigger of resource selection; where n and T are positive integers greater than or equal to 1. The above-mentioned "resource selection window" is the time slots [n + T1, n + T2] after the trigger of resource selection; T1 and T2 are integers greater than or equal to 1, and T2 is greater than or equal to T1.

[0149] A frequency-domain resource pool has been configured, where the maximum number of sub-channels in the frequency-domain resource pool is N subCH , and the corresponding set of sub-channels is The set of all candidate resources in each time slot within the resource selection window [n + T1, n + T2] is defined as Each candidate resource set is a set of consecutive sub-channel sets with a length of L subCH of subCH the number of sub-channels occupied by the PSSCH corresponding to the data to be transmitted, then the total number of candidate resource sets in each time slot is N subCH -L subCH +1.

[0150] For example, Figure 10 is a schematic diagram of the candidate resource set provided by the embodiment of the present application. As Figure 10 shown, the maximum number of sub-channels N subCH in the frequency-domain resource pool is 8, and the corresponding set of sub-channels is S = {S0, S1,..., S7}. The number of sub-channels L subCH occupied by the PSSCH corresponding to the data to be transmitted is 2, then the total number of candidate resource sets in each time slot is N subCH -L subCH +1 = 7. Then all candidate resource sets are C = {C0, C1, C2, C3, C4, C5, C6}, that is, as Figure 10As shown, the entire set of candidate resources is candidate resource set candidate_0, candidate resource set candidate_1, candidate resource set candidate_2, candidate resource set candidate_3, candidate resource set candidate_4, candidate resource set candidate_5, and candidate resource set candidate_6.

[0151] Figure 11 is a schematic diagram of the resource selection process for listening provided by the embodiments of this application. As Figure 11 shown, when performing resource selection, the terminal device listens to the resources in the frequency-domain resource pool within the resource listening window. In one example, the terminal device listens to the SCI sent by other terminal devices. If the listened SCI includes the resource set (or the reserved resource) reserved by other terminal devices, and this resource is within the resource selection window [n + T1, n + T2], then the terminal device performs RSRP measurement on the candidate resource set corresponding to this resource set (or the resource), and obtains a measurement result; if the value represented by the measurement result is greater than or equal to the preset threshold Th RSRP , then this resource set (or the resource) is excluded from the resource selection window. The above-mentioned preset threshold Th RSRP is a function determined according to the priority of the data indicated in the received SCI and the priority of the data to be transmitted by the terminal device. The terminal device selects the resource set (or the resource) for data transmission from the remaining candidate resource sets (or the remaining candidate resources).

[0152] In one example, to facilitate the first terminal device to determine the resource set indicated by the auxiliary information, the auxiliary information can indicate the size and position anchor of the resource set. At this time, the resource set is the resource set determined by the second terminal device. Since the auxiliary information indicates the size and position anchor of the resource set, after the first terminal device receives the scheduling information, it can know how many resource sets or resources the second terminal device has allocated for the first terminal device.

[0153] Then, the second terminal device uses the listened resources to send auxiliary information to the first terminal device.

[0154] In one example, the second terminal device sends auxiliary information to the first terminal device; among them, the auxiliary information is a separate signaling.

[0155] In another example, the auxiliary information is physical layer sidelink control information; that is, the second terminal device sends physical layer sidelink control information to the first terminal device, and this physical layer sidelink control information is used to assist the first terminal device in resource selection for data transmission. For example, the physical layer sidelink control information can be 1st stage SCI, or 2 nd stage SCI, or SCI.

[0156] In another example, the auxiliary information is MAC layer sidelink control information; that is, the second terminal device sends MAC layer sidelink control information to the first terminal device, and the MAC layer sidelink control information is used to assist the first terminal device in resource selection for data transmission. For example, the MAC layer sidelink control information may be SL MAC CE information.

[0157] In yet another example, the auxiliary information is RRC layer sidelink control information; that is, the second terminal device sends RRC layer sidelink control information to the first terminal device, and the RRC layer sidelink control information is used to assist the first terminal device in resource selection for data transmission. For example, the RRC layer sidelink control information may be PC5 RRC information.

[0158] Furthermore, the first terminal device determines the resources for data transmission according to the indication of the auxiliary information.

[0159] In one example, the auxiliary information indicates the resource set determined by the second terminal device, and the resource set determined by the second terminal device is the unoccupied resource determined by the second terminal device; furthermore, the first terminal device selects a suitable resource set from the resource set indicated by the auxiliary information according to the size of the data to be transmitted, and the resource set selected by the first terminal device can carry the data to be transmitted; at this time, the first terminal device determines the resources for data transmission.

[0160] In another example, the auxiliary information indicates the resource set determined by the second terminal device, and moreover, the first terminal device itself also detects the resource set, and the resource set detected by the first terminal device is the unoccupied resource determined by the first terminal device; the first terminal device selects a suitable resource set from the resource set indicated by the auxiliary information and the resource set detected by the first terminal device according to the size of the data to be transmitted, and the resource set selected by the first terminal device can carry the data to be transmitted; at this time, the first terminal device determines the resources for data transmission.

[0161] For example, in Figure 7In the application scenario shown, both terminal device B and terminal device C have data to send to terminal device A. Terminal device C uses resource 1 to send data to terminal device A. Terminal device B sends a first message to terminal device A; terminal device B is a hidden node of terminal device C, and terminal device B is unaware of the existence of terminal device C. However, terminal device A knows that terminal device C has used resource 1 to send data to terminal device A, and terminal device A can determine that resource 1 has been occupied. Consequently, the auxiliary information generated by terminal device A will not indicate resource 1; then, terminal device A returns the auxiliary information to terminal device B; terminal device B determines the resource for data transmission based on the auxiliary information; at this time, terminal device B determines that resource 1 has been occupied according to the auxiliary information and will no longer use resource 1. Terminal device B can use other resources or other resources indicated by the auxiliary information to send data to terminal device A. This can avoid terminal device C and terminal device B using the same resource to send data, prevent signal collisions and mutual interference during the data transmission process, and ensure the successful data transmission of both terminal device C and terminal device B.

[0162] For another example, in Figure 8 the application scenario shown, in the case of resource reuse, terminal device B has data to send to terminal device A, and terminal device C has data to send to terminal device D. Terminal device C uses resource 1 to send data to terminal device D. Terminal device B sends a first message to terminal device A; terminal device A can determine that resource 1 is not occupied, and thus the auxiliary information generated by terminal device A can indicate resource 1; then, terminal device A returns the auxiliary information to terminal device B; terminal device B determines the resource for data transmission based on the auxiliary information; at this time, terminal device B determines that resource 1 is not occupied according to the auxiliary information, and terminal device B can use resource 1 to send data to terminal device A. Furthermore, in the case of resource reuse, terminal device B can use this resource 1 to send data to terminal device A, and terminal device A will not be interfered by the signal sent by terminal device C on this resource 1; through the solution provided in this embodiment, resources are reasonably utilized, and the resource utilization efficiency is improved.

[0163] Figure 12 The signaling diagram provided in an embodiment of this application is for a device-to-device resource determination method, used to implement Figure 9 each step. As Figure 12 shown, this method includes:

[0164] S11. The first terminal device sends a first message to the second terminal device, where the first message is used to instruct the second terminal device to send auxiliary information.

[0165] S12. The second terminal device sends auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in resource selection for data transmission.

[0166] S13. The first terminal device determines the resource (or resource set) for data transmission according to the auxiliary information.

[0167] Here, S11 can refer to Figure 9 step S101 in Figure 9 S12 can refer to Figure 9 step S102 in

[0168] In this embodiment, the second terminal device receives the first information sent by the first terminal device, where the first information is used to instruct the second terminal device to send auxiliary information; the second terminal device sends the auxiliary information to the first terminal device, and the auxiliary information is used to assist the first terminal device in resource selection for data transmission. When the first terminal device needs to send data, the first terminal device requests auxiliary information from the second terminal device, and the auxiliary information is used to assist the first terminal device in resource selection for data transmission; the second terminal device generates the auxiliary information, and the second terminal device returns the auxiliary information to the first terminal device; the first terminal device determines the resource for data transmission according to the auxiliary information. Through the above process, when the first terminal device needs to send data, the second terminal device assists the first terminal device in determining the resource for data transmission, that is, other terminal devices (the terminal device receiving the data, or the terminal device not receiving the data) assist the first terminal device in determining the resource for data transmission, rather than the terminal device sending the data completely determining the resource for data transmission by itself; it can avoid different terminal devices using the same resource to send data, avoid signal collision and mutual interference in the data transmission process, and make the data transmission of different terminal devices all succeed; and for the case of resource reuse, the resources can be reasonably utilized and the resource utilization efficiency can be improved.

[0169] Figure 13 Another signaling diagram of the device-to-device based resource determination method provided by the embodiment of the present application is as Figure 13 shown, and the method includes:

[0170] S21. The first terminal device sends channel state information reference signal (CSI-RS) configuration information to the second terminal device, where the channel state information reference signal configuration information is used to indicate receiving the channel state information reference signal.

[0171] For example, in this embodiment, the first terminal device communicates with the second terminal device, the first terminal device is a data transmitter, the second terminal device is a data receiver, and the second terminal device is an auxiliary terminal. The second terminal device may not have the ability to schedule resources for data transmission, or may have the ability to schedule resources for data transmission, and there is no limitation on this.

[0172] The first terminal device sends CSI-RS configuration information to the second terminal device, where the CSI-RS configuration information is used to instruct the second terminal device to receive a channel state information reference signal. In one example, the CSI-RS configuration information is PC5 RRC information.

[0173] Optionally, step S21 is an optional step.

[0174] S22. The first terminal device sends a channel state information reference signal to the second terminal device, where the channel state information reference signal is used to determine channel state information.

[0175] Exemplarily, the first terminal device sends a CSI-RS to the second terminal device, and the CSI-RS is used by the second terminal device to determine channel state information. Thus, after receiving the CSI-RS, the second terminal device performs channel measurement according to the CSI-RS to obtain a measurement result; the second terminal device obtains the channel state information according to the measurement result. After the second terminal device obtains the channel state information, it is convenient to accurately determine the modulation and coding scheme (MCS) and other necessary information for data reception, which can further improve the ability to reasonably utilize resources.

[0176] Optionally, step S22 is an optional step.

[0177] S23. The first terminal device sends first information to the second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information.

[0178] In one example, a preset indication field or a preset bit position in the first information is used to instruct the second terminal device to send auxiliary information.

[0179] In one example, the first information is physical layer side link control information, or media intervention control layer side link control information, or radio resource control layer side link control information.

[0180] Exemplarily, before the first terminal device needs to send data to the second terminal device, it first sends the first information to the second terminal device. In this embodiment, the first information may also be referred to as an "assistance request".

[0181] In one example, the first terminal device can obtain resources by listening, and the resources obtained by listening are used to send an auxiliary request.

[0182] This step can refer to Figure 9 the step S101 shown in the figure, which will not be elaborated here.

[0183] S24. The first terminal device sends a buffer status report (BSR) message to the second terminal device, where the buffer status report message is used to indicate the size of the data to be transmitted.

[0184] In one example, a preset indication field or scrambled bits in the buffer status report message are used to indicate the size of the data to be transmitted.

[0185] In one example, the buffer status report message is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0186] Exemplarily, the first terminal device sends a BSR message to the second terminal device. To facilitate the second terminal device to determine appropriate resources for the first terminal device, the BSR message needs to indicate the size of the data to be transmitted by the first terminal device. For example, the BSR message includes an index of the size of the data to be transmitted in the buffer, or the BSR message includes the size of the data to be transmitted in the buffer; that is, the "size of the data to be transmitted" refers to the index of the size of the data to be transmitted in the buffer or the size of the data to be transmitted in the buffer. In one example, the first terminal device determines resources by listening, and the resources are used to transmit the BSR message; then, the first terminal device uses the resources obtained by listening to send the BSR message to the second terminal device.

[0187] For example, the BSR message includes an index of the size of the data to be transmitted in the buffer; x bits or binary digits can be used to indicate the index of the size value of the data to be transmitted by the first terminal device in the buffer, where x is a positive integer. There are 2 x buffer size levels. For example, when x = 5, there are 2 x buffer size levels, that is, there are 32 buffer size levels, which are respectively represented by indexes 0, 1,..., 31. One buffer size level corresponds to a buffer size range or a buffer size value. The unit of the buffer size can be byte or bit.

[0188] For example, Table 6.1.3.1-1 of the 3GPP protocol introduces buffer size levels (in bytes) for a 5-bit buffer size field.

[0189] Index BS value Index BS value Index BS value Index BS value 0 0 8 ≤102 16 ≤1446 24 ≤20516 1 ≤10 9 ≤142 17 ≤2014 25 ≤28581 2 ≤14 10 ≤198 18 ≤2806 26 ≤39818 3 ≤20 11 ≤276 19 ≤3909 27 ≤55474 4 ≤28 12 ≤384 20 ≤5446 28 ≤77284 5 ≤38 13 ≤535 21 ≤7587 29 ≤107669 6 ≤53 14 ≤745 22 ≤10570 30 ≤150000 7 ≤74 15 ≤1038 23 ≤14726 31 ＞150000

[0190] For another example, the BSR message includes the size of the data to be transmitted in the buffer, that is, the value of the size of the data to be transmitted in the buffer in the BSR message. The size of the data to be transmitted in the buffer can be represented by a real number or a string. For example, the size of the data to be transmitted in the buffer is 1023; if 1023 is represented by 10 bits, the size of the data to be transmitted in the buffer is 1111 1111 11; if represented by a real number, the size of the data to be transmitted in the buffer is 1023; or, if represented by a string, the size of the data to be transmitted in the buffer is 1023.

[0191] In one example, the first terminal device sends BSR information to the second terminal device. Among them, the BSR information is a separate signaling, and there are multiple indication fields in the BSR information. One preset indication field among the multiple indication fields can be used to indicate the size of the data to be transmitted; the position of the preset indication field in the BSR information and the size of the preset indication field are not restricted. Or, the BSR information is a separate signaling, and there are multiple bits in the BSR information. One preset bit among the multiple indication fields can be used to indicate the size of the data to be transmitted; the position of the preset bit in the BSR information and the size of the preset bit are not restricted.

[0192] In another example, the BSR information is physical layer sidelink control information; the preset indication field in the physical layer sidelink control information is used to indicate the size of the data to be transmitted, or the preset bit in the physical layer sidelink control information is used to indicate the size of the data to be transmitted. Among them, the physical layer sidelink control information can indicate the size of the data to be transmitted in an explicit manner, or the physical layer sidelink control information can indicate the size of the data to be transmitted in an implicit manner. For example, the physical layer sidelink control information can be 1 st stage SCI, or 2 nd stage SCI, or SCI.

[0193] For example, the BSR information is 2 nd stage SCI, 2 ndThere is a preset indication field in the stage SCI; the size of the data to be transmitted is indicated in this preset indication field; for example, 2 nd The preset indication field in the stage SCI includes a 5-bit buffer size field, and this 5-bit buffer size field represents BSR information. Also, 2 nd The stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, that is, 2 nd The stage SCI includes the sending 2 nd The identifier of the terminal device of the stage SCI, and the receiving 2 nd The identifier of the terminal device of the stage SCI, so that the second terminal device knows that it is the first terminal device that is sending BSR information to itself. At this time, the BSR information can indicate the size of the data to be transmitted in an explicit manner.

[0194] For example, the BSR information is 1 st The stage SCI, 1 st There is a preset indication field in the stage SCI; the size of the data to be transmitted is indicated in this preset indication field; for example, 1 st The preset indication field in the stage SCI includes a 5-bit buffer size field, and this 5-bit buffer size field represents BSR information. Also, the second terminal device receives 1 st Before receiving the stage SCI or after receiving the stage SCI 1 st the second terminal device also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identification information is 2 nd The stage SCI; thus, the second terminal device knows that it is the first terminal device that is sending BSR information to itself. At this time, the BSR information can indicate the size of the data to be transmitted in an explicit manner.

[0195] For example, the BSR information is 2 nd The stage SCI; 2 nd There is a preset bit in the stage SCI; the size of the data to be transmitted is indicated in this preset bit. For example, x-bit scrambling is used on the CRC of the 2nd stage SCI to indicate the size of the data to be transmitted, where x is a positive integer; also, 2 nd The stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, that is, 2 nd The stage SCI includes the sending 2 nd The identifier of the terminal device of the stage SCI, and the receiving 2nd The identifier of the terminal device of stage SCI, so that the second terminal device knows that it is the first terminal device sending BSR information to itself. At this time, the BSR information can implicitly indicate the size of the data to be transmitted.

[0196] For example, the first terminal device sends 2 nd stage SCI to the second terminal device, and 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; 2 nd There is a CRC in 2 nd stage SCI. The CRC before scrambling of 2 nd stage SCI is a 24-bit bit sequence 0101 1010 0101 1010 0101 1010; the BSR information uses 11111 to indicate that the buffer size is greater than 150000 bytes, and 5-bit scrambling is used on the last 5 bits of the CRC in 2 nd stage SCI, and then 11111 is used for scrambling the last 5 bits of the CRC in 2 nd stage SCI, and the scrambled CRC of 2

[0197] For example, the BSR information is 1 st stage SCI; 1 st There is a preset bit in 1 st stage SCI; this preset bit is used to indicate the size of the data to be transmitted. For example, x-bit scrambling is used on the CRC in 1 st stage SCI to indicate the size of the data to be transmitted, where x is a positive integer. And the second terminal device receives 1 st stage SCI before or after receiving 1 nd stage SCI, and also needs to receive the identifier information sent by the first terminal device. The identifier information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identifier information is 2

[0198] For example, a first terminal device sends 1 to a second terminal device st stage SCI and 2 nd stage SCI, where 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; 1 st There is a CRC in 1 stage SCI, 1 st The CRC of 1 stage SCI before scrambling is a 24-bit bit sequence 0101 1010 0101 1010 0101 1010; the BSR information is represented by 11111 indicating that the buffer size is greater than 150,000 words byte, and 5-bit scrambling is used on 1 st the last 5 bits of the CRC of 1 stage SCI, then 11111 is used for scrambling 1 st the last 5 bits of the CRC of 1 stage SCI, and 1 st the scrambled CRC of stage SCI is a 24-bit bit sequence 0101 1010 0101 1010 0100 0101. Thus, after the second terminal device receives the scrambled CRC, it attempts to descramble the CRC using all possible 5-bit BSR information. When the descrambling is successful using 11111, the second terminal device can learn that the buffer size of the first terminal device is greater than 150,000 byte.

[0199] In another example, the BSR information is MAC layer sidelink control information; a preset indication field in the MAC layer sidelink control information is used to indicate the size of the data to be transmitted, or a preset bit in the MAC layer sidelink control information is used to indicate the size of the data to be transmitted. Among them, the MAC layer sidelink control information can indicate the size of the data to be transmitted in an explicit manner, or the MAC layer sidelink control information can indicate the size of the data to be transmitted in an implicit manner. For example, the MAC layer sidelink control information can be SL MAC CE information.

[0200] For example, the BSR information is SL MAC CE information, and there is a preset indication field in the SL MAC CE information, and the preset indication field is used to indicate the size of the data to be transmitted; for example, the preset indication field in the SL MAC CE information includes a 5-bit buffer size field, and the 5-bit buffer size field represents the BSR information. And, before or after the second terminal device receives the SL MAC CE information, it also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identification information is 2 ndstage SCI; thus, the second terminal device knows that the first terminal device is sending BSR information to itself. At this time, the BSR information can indicate the size of the data to be transmitted in an explicit manner.

[0201] In another example, the BSR information is RRC layer sidelink control information; a preset indication field in the RRC layer sidelink control information is used to indicate the size of the data to be transmitted, or a preset bit in the RRC layer sidelink control information is used to indicate the size of the data to be transmitted. Among them, the RRC layer sidelink control information can indicate the size of the data to be transmitted in an explicit manner, or the RRC layer sidelink control information can indicate the size of the data to be transmitted in an implicit manner. For example, the RRC layer sidelink control information can be PC5 RRC information.

[0202] For example, the BSR information is PC5 RRC information, and there is a preset indication field in the PC5 RRC information; the preset indication field is used to indicate the size of the data to be transmitted; for example, the preset indication field in the PC5 RRC information includes a 5-bit buffer size field, and this 5-bit buffer size field represents the BSR information. Moreover, before or after receiving the PC5 RRC information, the second terminal device also needs to receive identification information sent by the first terminal device, and the identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device knows that the first terminal device is sending BSR information to itself. At this time, the BSR information can indicate the size of the data to be transmitted in an explicit manner.

[0203] Among them, there is no requirement for the execution order among steps S21, S22, S23, and S24.

[0204] S25. The second terminal device determines auxiliary information according to the buffer status report message, and the auxiliary information is used to indicate the set of unoccupied resources (or resources).

[0205] In one example, the auxiliary information is specifically used to indicate the size and position anchor of the resources for data transmission.

[0206] In one example, step S25 specifically includes the following process: determining the size of the resources for data transmission according to the buffer status report message; determining the auxiliary information according to the size of the resources for data transmission.

[0207] Exemplarily, after receiving the BSR information and the first information, the second terminal device determines, according to the first information, that auxiliary information needs to be returned to the first terminal device; however, before returning the auxiliary information, it is necessary to first determine the auxiliary information. The second terminal device determines the auxiliary information according to the BSR message.

[0208] In one example, at step S22, the second terminal device can already obtain the channel state information through the measurement result of the CSI-RS, and the BSR message indicates the size of the data to be transmitted; the second terminal device can then determine the size of the resources required for the first terminal device to perform data transmission according to the channel state information and the BSR information; then, the second terminal device listens with this size as the granularity, determines the set of resources or resources that are not occupied, and further determines the available set of resources or resources; the second terminal device generates auxiliary information, and the auxiliary information indicates the set of resources or resources that are not occupied.

[0209] In another example, after receiving the BSR information, since the BSR message indicates the size of the data to be transmitted, the second terminal device can determine the size of the resources required for the first terminal device to perform data transmission according to the BSR; then, the second terminal device listens with this size as the granularity, determines the set of resources or resources that are not occupied, and further determines the available set of resources or resources; the second terminal device generates auxiliary information, and the auxiliary information indicates the set of resources or resources that are not occupied.

[0210] Among them, the granularity of the resource size can be a sub-channel, or a resource block group, or a resource block, etc.; there is no limitation on the granularity of the resource size.

[0211] To facilitate the first terminal device to determine the location of the resources, the auxiliary information can indicate the size of the resources for data transmission and the location anchor of the resources for data transmission. Or rather, the auxiliary information can indicate the size of the set of resources for data transmission and the location anchor of the set of resources for data transmission. Because, the "resources for data transmission" are not necessarily 1 resource, but a set of resources composed of at least one resource. Among them, the sizes of different resources can be the same or different, but the location anchors of different resources are different. The location anchor refers to the starting point of the resource, or the ending point of the resource, or the midpoint of the resource, etc.

[0212] Below, taking "resources" as an example for introduction, the auxiliary information indicates a plurality of unoccupied resources.

[0213] In one example, the auxiliary information includes first indication information for each resource, and the first indication information is used to indicate the size and location anchor of the resource. At this time, the auxiliary information can indicate multiple unoccupied resources, and each resource has its own first indication information, that is, the first indication information is an indication of an unoccupied resource, and the first indication information can be represented by an index value; the first indication information for each resource indicates the size and location anchor of the resource.

[0214] In another example, the auxiliary information includes second indication information for each resource and third indication information for each resource. The second indication information is used to indicate the size of the resource, and the third indication information is used to indicate the location anchor of the resource. At this time, the auxiliary information can indicate multiple unoccupied resources, and each resource has its own second indication information and third indication information. For example, the auxiliary information includes an indication for each resource, and the indication can be represented by a field; the field includes sub-field 1 and sub-field 2, where sub-field 1 indicates the size of the resource and sub-field 2 indicates the location anchor of the resource.

[0215] In yet another example, the auxiliary information includes fourth indication information and fifth indication information for each resource; the fourth indication information is used to indicate the size of the resource, and the size of each resource is the same; the fifth indication information is used to indicate the location anchor of the resource. At this time, the auxiliary information can indicate multiple unoccupied resources. Since the sizes of the resources are the same, the same fourth indication information can be used to indicate the size of the resources. For example, a field is used to uniformly indicate the size of the resources; each resource has its own fifth indication information, and the fifth indication information is used to indicate the location anchor of the resource, that is, the location anchors of the resources are indicated by different fields respectively.

[0216] In addition, the number of resources indicated by the auxiliary information is the number of all unoccupied resources; or, the number of resources indicated by the auxiliary information is a preset number.

[0217] In one example, there is no limit to the number of resources indicated by the auxiliary information, that is, if the second terminal device determines all unoccupied resources, then the second terminal device can use the auxiliary information to indicate all unoccupied resources. It can be seen that the auxiliary information sent by the second terminal device to the first terminal device can indicate as many unoccupied resources as possible.

[0218] In another example, the number of resources indicated by the assistance information is restricted. That is, the assistance information sent by the second terminal device to the first terminal device can indicate N unoccupied resources, where N is a positive integer greater than or equal to 1. If the number of unoccupied resources determined by the second terminal device is N, the number of resources indicated by the assistance information is N. If the number of unoccupied resources determined by the second terminal device is greater than N, N resources are selected therefrom. For example, N resources with the minimum noise and interference power on the resources are selected; the number of resources indicated by the assistance information is N. If the number of unoccupied resources determined by the second terminal device is less than N, for example, M (where M is a positive integer greater than or equal to 1 and less than N), the assistance information indicates these M resources; or the assistance information indicates these M resources and the remaining fields for indicating resources in the assistance information are set to empty (or zero).

[0219] For example, the number of resources indicated by the assistance information is restricted to 3. If the number of unoccupied resources determined by the second terminal device is 3, the number of resources indicated by the assistance information is 3. If the number of unoccupied resources determined by the second terminal device is greater than 3, 3 resources are selected therefrom. For example, 3 resources with the minimum noise and interference power on the resources are selected; the number of resources indicated by the assistance information is 3. If the number of unoccupied resources determined by the second terminal device is less than 3, for example, 2, the assistance information indicates these 2 resources, or the assistance information indicates these 2 resources and the field for the third available resource is set to empty (or zero).

[0220] When restricting the number of resources indicated by the assistance information, the number of resources can be specified. For example, the maximum value of the number of resources indicated by the assistance information is 3.

[0221] Alternatively, when restricting the number of resources indicated by the assistance information, the first terminal device sends second information to the second terminal device, where the second information is for the maximum number of resources; thus, the first terminal device restricts the maximum number of resources returned by the second terminal device. In one example, the second information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0222] In one example, the first terminal device sends second information to the second terminal device; where the second information is a separate signaling.

[0223] In another example, the second information is physical layer sidelink control information; that is, the first terminal device sends physical layer sidelink control information to the second terminal device, and the physical layer sidelink control information is for the maximum number of resources. For example, the physical layer sidelink control information can be 1 ststage SCI, or 2 nd stage SCI, or SCI.

[0224] In another example, the second information is MAC layer sidelink control information; that is, the first terminal device sends MAC layer sidelink control information to the second terminal device, and the MAC layer sidelink control information is used for the maximum number of resources. For example, the MAC layer sidelink control information may be SL MAC CE information.

[0225] In yet another example, the second information is RRC layer sidelink control information; that is, the first terminal device sends RRC layer sidelink control information to the second terminal device, and the RRC layer sidelink control information is used for the maximum number of resources. For example, the RRC layer sidelink control information may be PC5 RRC information.

[0226] S26. The second terminal device sends auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0227] In one example, the auxiliary information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0228] Exemplarily, refer to Figure 9 the steps shown in S102, which will not be elaborated here.

[0229] S27. The first terminal device determines resources for data transmission according to the auxiliary information.

[0230] In one example, step S27 specifically includes the following implementation manners:

[0231] The first implementation manner of step S27: Select resources from the resource set indicated by the auxiliary information as the resources for data transmission, where the auxiliary information is used to indicate an unoccupied resource set (or resources).

[0232] In one example, the first implementation manner of step S27 specifically includes: randomly selecting resources from the resource set indicated by the auxiliary information as the resources for data transmission; or selecting the resource with the highest priority from the resources in the resource set indicated by the auxiliary information as the resources for data transmission.

[0233] The second implementation manner of step S27: Determine resources for data transmission according to the resource set indicated by the auxiliary information and the detected resource set.

[0234] In one example, the second implementation manner of step S27 specifically includes: determining the common resources between the resource set indicated by the auxiliary information and the resource set detected; and selecting a resource from the common resources as the resource for data transmission.

[0235] Exemplarily, since the auxiliary information can indicate the unoccupied resources, the first terminal device can determine the resources for data transmission according to the auxiliary information.

[0236] In one example, the auxiliary information can indicate the set of unoccupied resources; the first terminal device can select a suitable resource set from the resource set indicated by the auxiliary information according to the size of the data to be transmitted, and the resource set selected by the first terminal device can carry the data to be transmitted; at this time, the first terminal device determines the resources for data transmission.

[0237] For example, the first terminal device randomly selects a resource that can carry the data to be transmitted from the resource set indicated by the auxiliary information as the resource for data transmission.

[0238] For another example, if the resources in the resource set indicated by the auxiliary information have priorities, the first terminal device can use the resource with the highest priority as the resource for data transmission according to the priorities of the resources.

[0239] In another example, the first terminal device can detect resources by itself. For example, it can detect resources by using the size of the resources indicated by the auxiliary information, or by using the size of the data to be transmitted indicated by the BSR information. At this time, the auxiliary information indicates the resource set determined by the second terminal device, and the first terminal device also detects a resource set by itself. The resource set detected by the first terminal device is the unoccupied resource set determined by the first terminal device. The first terminal device selects a suitable resource set from the resource set indicated by the auxiliary information and the resource set detected by the first terminal device according to the size of the data to be transmitted, and the resource set selected by the first terminal device can carry the data to be transmitted. At this time, the first terminal device determines the resources for data transmission. Among them, when the first terminal device detects resources by using the size of the resources indicated by the auxiliary information, that is, the first terminal device detects resources by using the resource granularity indicated by the auxiliary information, the first terminal device does not need to rely on the channel quality indicator (CQI) of the second terminal device to determine the intensity of the detected resources.

[0240] For example, the first terminal device takes the intersection of the resource set indicated by the auxiliary information and the resource set detected by the first terminal device to obtain the common resources; then, randomly selects resources that can carry the data to be transmitted from the common resources as the resources for data transmission; or, takes the resource with the highest priority from the common resources as the resource for data transmission.

[0241] Among them, the "resources for data transmission" can be frequency-domain resources, time-domain resources, or time-frequency resources.

[0242] S28. The first terminal device sends sidelink control information to the second terminal device.

[0243] Exemplarily, the first terminal device sends sidelink control information to the second terminal device, and the sidelink control information is used to indicate information such as the MCS for data transmission. That is, before the first terminal device sends data to the second terminal device, the first terminal device needs to indicate the necessary information for data reception such as the MCS; then, the first terminal device uses the sidelink control information to inform the second terminal device of the necessary information for data reception.

[0244] In one example, the first terminal device uses the resources for data transmission in step S27 to send sidelink control information to the second terminal device.

[0245] In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1st stage SCI, or 2nd stage SCI, or SCI.

[0246] Step S28 is an optional step. If step S28 is not executed, it can be stipulated in the protocol that both the first terminal device and the second terminal device already know the above necessary information for data reception.

[0247] Among them, there is no restriction on the execution order between step S28 and the above steps S21 - S27, as long as step S28 is executed before step S29.

[0248] S29. The first terminal device sends data to the second terminal device according to the resources for data transmission.

[0249] Exemplarily, the first terminal device uses the resources for data transmission obtained in step S27 to send data to the second terminal device.

[0250] In this embodiment, the first terminal device is the data sender, and the second terminal device is the data receiver; the first terminal device sends the first information to the second terminal device, and the first information is used to instruct the second terminal device to send auxiliary information, and the auxiliary information is used to assist the first terminal device in selecting resources for data transmission. For example, the auxiliary information is used to indicate the unoccupied resources; furthermore, the resources provided by the second terminal device can be used as a reference for the first terminal device to select resources; the auxiliary information can help the first terminal device exclude the resources occupied by the hidden terminal device, avoid different terminal devices using the same resource to send data, avoid signal collision and mutual interference during the data transmission process, thereby improving the success rate of the first terminal device transmitting data to the second terminal device; and, for the case of resource reuse, the resources can be reasonably utilized, and the resource utilization efficiency can be improved. Also, the first terminal device sends the BSR information to the second terminal device, so that when the second terminal device determines the auxiliary information, it can more reasonably calculate the resource granularity to be listened according to the size of the data to be transmitted indicated by the BSR information, and then determine the resources suitable for the first terminal device to perform data transmission, so that the resources are reasonably utilized.

[0251] Figure 14 Another signaling diagram of the device-to-device based resource determination method provided by the embodiments of this application is as Figure 14 shown, and this method includes:

[0252] S31. The first terminal device sends the channel state information reference signal configuration information to the second terminal device, where the channel state information reference signal configuration information is used to indicate receiving the channel state information reference signal.

[0253] Exemplarily, in this embodiment, the first terminal device is the data sender, and the second terminal device is the auxiliary end (the second terminal device is not the data receiver); the third terminal device is the data receiver. Among them, the second terminal device may or may not have the ability to schedule resources for data transmission, and this is not limited.

[0254] This step can refer to Figure 13 the step S21 shown, and will not be elaborated. Step S31 is an optional step.

[0255] S32. The first terminal device sends the channel state information reference signal to the second terminal device, where the channel state information reference signal is used to determine the channel state information.

[0256] Exemplarily, this step can refer to Figure 13 the step S22 shown, and will not be elaborated. Step S32 is an optional step.

[0257] S33. The first terminal device sends first information to the second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information.

[0258] Exemplarily, for this step, reference can be made to Figure 13 step S23 shown, which will not be elaborated here.

[0259] S34. The first terminal device sends a buffer status report message to the second terminal device, where the buffer status report message is used to indicate the size of the data to be transmitted.

[0260] Exemplarily, for this step, reference can be made to Figure 13 step S24 shown, which will not be elaborated here.

[0261] S35. The second terminal device determines auxiliary information according to the buffer status report message, where the auxiliary information is used to indicate the set of unoccupied resources (or resources).

[0262] Exemplarily, for this step, reference can be made to Figure 13 step S25 shown, which will not be elaborated here.

[0263] S36. The second terminal device sends the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0264] Exemplarily, for this step, reference can be made to Figure 13 step S26 shown, which will not be elaborated here.

[0265] S37. The first terminal device determines the resources for data transmission according to the auxiliary information.

[0266] Exemplarily, for this step, reference can be made to Figure 13 step S27 shown. Different from Figure 13 step S27, the resources for data transmission determined in step S37 are the resources required when the first terminal device transmits data to the third terminal device.

[0267] In one example, the auxiliary information can indicate the set of unoccupied resources; the first terminal device can, according to the size of the data to be transmitted, select a suitable set of resources from the set of resources indicated by the auxiliary information, and the set of resources selected by the first terminal device can carry the data to be transmitted; at this time, the first terminal device determines the resources for data transmission, and the resources for data transmission are the resources required when the first terminal device transmits data to the third terminal device.

[0268] In another example, the first terminal device can listen for resources by itself. For example, it can listen for resources using the size of the resources indicated by the auxiliary information, or listen for resources using the size of the data to be transmitted indicated by the BSR information. At this time, the auxiliary information indicates the resource set determined by the second terminal device, and the first terminal device also listens for the resource set by itself. The resource set listened for by the first terminal device is the unoccupied resource set determined by the first terminal device. The first terminal device selects a suitable resource set from the resource set indicated by the auxiliary information and the resource set listened for by the first terminal device according to the size of the data to be transmitted. The resource set selected by the first terminal device can carry the data to be transmitted. At this time, the first terminal device determines the resources for data transmission, and the resources for data transmission are the resources required when the first terminal device transmits data to the third terminal device.

[0269] Among them, the "resources for data transmission" can be frequency domain resources, or time domain resources, or time-frequency resources.

[0270] S38. The first terminal device sends sidelink control information to the third terminal device.

[0271] Exemplarily, the first terminal device sends sidelink control information to the third terminal device, and the sidelink control information is used to indicate information such as the MCS for data transmission. That is, before the first terminal device sends data to the third terminal device, the first terminal device needs to indicate the necessary information for data reception such as the MCS. Then, the first terminal device uses the sidelink control information to inform the third terminal device of the necessary information for data reception.

[0272] In one example, the first terminal device uses the resources for data transmission in step S37 to send sidelink control information to the third terminal device.

[0273] In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1st stage SCI, or 2nd stage SCI, or SCI.

[0274] Step S38 is an optional step. If step S38 is not executed, it can be stipulated in the protocol that both the first terminal device and the third terminal device already know the above necessary information for data reception.

[0275] Among them, the execution order between step S38 and the above steps S31 - S37 is not restricted, as long as step S38 is executed before step S39.

[0276] S39. The first terminal device sends data to the third terminal device according to the resources for data transmission.

[0277] Exemplarily, the first terminal device uses the resources for data transmission obtained in step S37 to send data to the third terminal device.

[0278] In this embodiment, the first terminal device is the data sender, the second terminal device is the auxiliary device, and the third terminal device is the data receiver; the first terminal device sends the first information to the second terminal device, and the first information is used to instruct the second terminal device to send auxiliary information, and the auxiliary information is used to assist the first terminal device in selecting resources for data transmission. For example, the auxiliary information is used to indicate the unoccupied resources; furthermore, although the second terminal device is not the data receiver, the resources provided by the second terminal device can be used as a reference for the first terminal device to select resources; the auxiliary information can help the first terminal device exclude the resources occupied by the hidden terminal device, avoid different terminal devices using the same resource to send data, avoid signal collision and mutual interference during the data transmission process, thereby improving the success rate of the first terminal device in transmitting data to the third terminal device; and, for the case of resource reuse, the resources can be reasonably utilized and the resource utilization efficiency can be improved. Also, the first terminal device sends the BSR information to the second terminal device, so that when determining the auxiliary information, the second terminal device can more reasonably calculate the resource granularity to be listened according to the size of the data to be transmitted indicated by the BSR information, and then determine the resources suitable for the first terminal device to perform data transmission, so that the resources are reasonably utilized.

[0279] Figure 15 Another signaling diagram of the device-to-device based resource determination method provided by the embodiments of the present application is as Figure 15 shown, and the method includes:

[0280] S41. The first terminal device sends channel state information reference signal configuration information to the second terminal device, where the channel state information reference signal configuration information is used to indicate receiving the channel state information reference signal.

[0281] Exemplarily, in this embodiment, communication is performed between the first terminal device and the second terminal device. The first terminal device is the data sender, the second terminal device is the data receiver, and the second terminal device is the auxiliary device. Among them, the second terminal device may not have the ability to schedule resources for data transmission, or may have the ability to schedule resources for data transmission, which is not limited herein.

[0282] This step can refer to Figure 13 the step S21 shown and will not be elaborated here. Step S41 is an optional step.

[0283] S42. The first terminal device sends a channel state information reference signal to the second terminal device, where the channel state information reference signal is used to determine channel state information.

[0284] Exemplarily, for this step, reference may be made to Figure 13 step S22 shown above, which will not be elaborated. Step S42 is an optional step.

[0285] S43. The first terminal device sends first information to the second terminal device, where the first information is specifically used to instruct the second terminal device to send auxiliary information periodically.

[0286] In one example, the first indication field or the first bit in the first information is used to indicate the periodic time interval for sending the auxiliary information, and the second indication field or the second bit in the first information is used to indicate the time point for sending the auxiliary information.

[0287] In one example, the first information is physical layer sidelink control information, or media access control layer sidelink control information, or radio resource control layer sidelink control information.

[0288] Exemplarily, before the first terminal device needs to send data to the second terminal device, it first sends the first information to the second terminal device. In this embodiment, the first information may also be referred to as "auxiliary information sending configuration information".

[0289] When the first terminal device needs to send data, the first terminal device sends the first information to the second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information periodically, and the auxiliary information is used to assist the first terminal device in resource selection for data transmission. In one example, the first terminal device can obtain resources through listening and use the listened resources to send the first information to the second terminal device. Since the first information instructs the second terminal device to feedback auxiliary information periodically, it is not necessary for the first terminal device to continuously trigger the second terminal device to feedback auxiliary information, thereby saving the signaling overhead of the first terminal device.

[0290] The first information has multiple indication fields. One first indication field among the multiple indication fields can be used to indicate the periodic time interval for sending the auxiliary information; one second indication field among the multiple indication fields can be used to indicate the time point for sending the auxiliary information; the position of the first indication field in the first information and the size of the first indication field, the position of the second indication field in the first information and the size of the second indication field are not limited.

[0291] Alternatively, the first information has multiple bit positions. One first bit position among the multiple bit positions can be used to indicate the periodic time interval for sending the auxiliary information; one second bit position among the multiple bit positions can be used to indicate the time point for sending the auxiliary information. The position of the first bit position in the first information, the size of the first bit position, the position of the second bit position in the first information, and the size of the second bit position are not restricted.

[0292] The first information has multiple indication fields. One first indication field among the multiple indication fields can be used to indicate the periodic time interval for sending the auxiliary information; the first information has multiple bit positions. One second bit position among the multiple bit positions can be used to indicate the time point for sending the auxiliary information. The position of the first indication field in the first information, the size of the first indication field, the position of the second bit position in the first information, and the size of the second bit position are not restricted.

[0293] Alternatively, the first information has multiple bit positions. One first bit position among the multiple bit positions can be used to indicate the periodic time interval for sending the auxiliary information; the first information has multiple indication fields. One second indication field among the multiple indication fields can be used to indicate the time point for sending the auxiliary information. The position of the first bit position in the first information, the size of the first bit position, the position of the second indication field in the first information, and the size of the second indication field are not restricted.

[0294] In one example, the "periodic time interval for sending the auxiliary information" can be the actual time interval for sending the auxiliary information; or, the "periodic time interval for sending the auxiliary information" can be the index of the actual time interval for sending the auxiliary information. In this case, an index table between the actual time interval and the index needs to be established.

[0295] For example, the "periodic time interval for sending the auxiliary information" is the actual time interval for sending the auxiliary information. If the actual time interval is 4 subframes, then 4 can be used to indicate the "periodic time interval for sending the auxiliary information".

[0296] For another example, the "periodic time interval for sending the auxiliary information" can be the index of the actual time interval for sending the auxiliary information. If the actual time interval is 4 subframes, according to the index table between the actual time interval and the index, the index is 1, then 1 is used to indicate the "periodic time interval for sending the auxiliary information".

[0297] In one example, the "time point for sending the auxiliary information" can be an absolute time, or it can be a relative time.

[0298] For example, the "time point for sending auxiliary information" is an absolute time. If the "time point for sending auxiliary information" is 3 subframes, then 3 is used to indicate the "time point for sending auxiliary information".

[0299] For another example, the "time point for sending auxiliary information" is a relative time. If the "time point for sending auxiliary information" is 3 time slots, it is determined that after 3 time slots after receiving the first information, the second terminal device starts to periodically send auxiliary information.

[0300] Among them, the unit of time can be a time slot, or a subframe, or a transmission time interval (TTI), or a symbol, or a frame, or a millisecond, or a second, etc., without limitation.

[0301] In one example, the first terminal device sends the first information to the second terminal device. Among them, the first information is a single signaling.

[0302] In another example, the first information is physical layer sidelink control information; the first indication field or the first bit in the physical layer sidelink control information is used to indicate the periodic time interval for sending auxiliary information, and the second indication field or the second bit in the physical layer sidelink control information is used to indicate the time point for sending auxiliary information. For example, the physical layer sidelink control information can be 1 st stage SCI, or 2 nd stage SCI, or, SCI.

[0303] For example, the first information is 2 nd stage SCI, 2 nd stage SCI has a first indication field and a second indication field. The first indication field is used to indicate the periodic time interval for sending auxiliary information, and the second indication field is used to indicate the time point for sending auxiliary information. The value in the first indication field can be represented by an integer or a string, without limitation; furthermore, the value in the first indication field indicates the periodic time interval for sending auxiliary information. The value in the second indication field can be represented by an integer or a string, without limitation; furthermore, the value in the second indication field indicates the time point for sending auxiliary information. And, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; thus, the second terminal device can know that it is the first terminal device that requests it to periodically send auxiliary information.

[0304] For example, the first information is 1 ststage SCI, 1 st In stage SCI, there are a first indication field and a second indication field. The first indication field is used to indicate the periodic time interval for sending auxiliary information, and the second indication field is used to indicate the time point for sending auxiliary information. The value in the first indication field can be represented by an integer or a string, and there is no limitation on this; furthermore, the value in the first indication field indicates the periodic time interval for sending auxiliary information. The value in the second indication field can be represented by an integer or a string, and there is no limitation on this; furthermore, the value in the second indication field indicates the time point for sending auxiliary information. And, the second terminal device receives 1 st before receiving stage SCI or receives 1 st after receiving stage SCI, the second terminal device also needs to receive the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stageSCI; thus, the second terminal device can know that it is the first terminal device that requests it to periodically send auxiliary information.

[0305] For example, the first information is 2 nd stage SCI; 2 nd In stage SCI, there are a first bit and a second bit. The first bit is used to indicate the periodic time interval for sending auxiliary information, and the second bit is used to indicate the time point for sending auxiliary information. The first bit can be a bit sequence, and the second bit can be a bit sequence; it is possible to 2 nd scramble the original bits in stage SCI to obtain the first bit and the second bit. And, 2 nd stageSCI itself includes the identification of the first terminal device and the identification of the second terminal device; thus, the second terminal device can know that it is the first terminal device that requests it to periodically send auxiliary information.

[0306] For example, the first information is 1 st stage SCI; 1 st In stage SCI, there are a first bit and a second bit. The first bit is used to indicate the periodic time interval for sending auxiliary information, and the second bit is used to indicate the time point for sending auxiliary information. The first bit can be a bit sequence, and the second bit can be a bit sequence; it is possible to 1 st scramble the original bits in stage SCI to obtain the first bit and the second bit. And, the second terminal device receives 1 st before receiving stage SCI or receives 1 stAfter stage SCI, the second terminal device also needs to receive the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device. For example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that requests it to periodically send auxiliary information.

[0307] In another example, the first information is MAC layer sidelink control information; the first indication field or the first bit in the MAC layer sidelink control information is used to indicate the periodic time interval for sending the auxiliary information, and the second indication field or the second bit in the MAC sidelink control information is used to indicate the time point for sending the auxiliary information. For example, the MAC layer sidelink control information may be SL MAC CE information.

[0308] For example, the first information is SL MAC CE information. There are a first indication field and a second indication field in the SL MAC CE information. The first indication field is used to indicate the periodic time interval for sending the auxiliary information, and the second indication field is used to indicate the time point for sending the auxiliary information. The value in the first indication field can be represented by an integer or a string, and no limitation is imposed thereon; furthermore, the value in the first indication field indicates the periodic time interval for sending the auxiliary information. The value in the second indication field can be represented by an integer or a string, and no limitation is imposed thereon; furthermore, the value in the second indication field indicates the time point for sending the auxiliary information. Also, before or after receiving the SL MAC CE information, the second terminal device also needs to receive the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device. For example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that requests it to periodically send auxiliary information.

[0309] In yet another example, the first information is RRC layer sidelink control information; the first indication field or the first bit in the RRC layer sidelink control information is used to indicate the periodic time interval for sending the auxiliary information, and the second indication field or the second bit in the RRC sidelink control information is used to indicate the time point for sending the auxiliary information. For example, the RRC layer sidelink control information may be PC5 RRC information.

[0310] For example, the first information is PC5 RRC information; there are a first indication field and a second indication field in the PC5 RRC information. The first indication field is used to indicate the periodic time interval for sending the auxiliary information, and the second indication field is used to indicate the time point for sending the auxiliary information. The value in the first indication field can be represented by an integer or a string, and there is no limitation on this; furthermore, the value in the first indication field indicates the periodic time interval for sending the auxiliary information. The value in the second indication field can be represented by an integer or a string, and there is no limitation on this; furthermore, the value in the second indication field indicates the time point for sending the auxiliary information. Also, before or after the second terminal device receives the PC5 RRC information, it also needs to receive the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that requests it to periodically send the auxiliary information.

[0311] S44. The first terminal device sends a buffer status report message to the second terminal device, where the buffer status report message is used to indicate the size of the data to be transmitted.

[0312] In one example, a preset indication field or scrambled bits in the buffer status report message are used to indicate the size of the data to be transmitted.

[0313] In one example, the buffer status report message is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0314] Exemplarily, the first terminal device sends a BSR message to the second terminal device. In order to facilitate the second terminal device to determine appropriate resources for the first terminal device, the BSR message needs to indicate the size of the data to be transmitted by the first terminal device. This step can refer to Figure 13 the steps shown in Figure 13 Step S24; in this embodiment, compared with

[0315] the steps shown in

[0316] In one example, the first terminal device may periodically send BSR information. At this time, the periodic time interval for sending BSR information is the same as the periodic time interval for sending auxiliary information; that is, the period of the BSR is the same as the period of the auxiliary information. Alternatively, there is a multiple relationship between the periodic time interval for sending BSR information and the periodic time interval for sending auxiliary information; that is, there is a multiple relationship between the period of the BSR and the period of the auxiliary information. For example, if the period for sending auxiliary information is 20 subframes, then the period for sending BSR information can be 10 subframes, or 20 subframes, or 40 subframes.

[0317] In one example, the first terminal device may send BSR information aperiodically. At this time, since the first terminal device knows the periodic time interval and time point at which the second terminal device sends auxiliary information, the first terminal device only needs to send BSR information to the second terminal device before the second terminal device sends auxiliary information. For example, if the period of the auxiliary information is T, and the second terminal device sends auxiliary information at time 0, time T, time 2T, and time 3T; then the first terminal device may send or not send BSR information at time [0, T], time [T, 2T], time [2T, 3T], or may send BSR information at any moment within these time periods.

[0318] S45. The second terminal device determines auxiliary information according to the buffer status report message, and the auxiliary information is used to indicate the set of resources (or resources) that are not occupied.

[0319] In one example, the auxiliary information is specifically used to indicate the size and location anchor of the resources for data transmission.

[0320] In one example, step S55 specifically includes the following process: determining the size of the resources for data transmission according to the buffer status report message; and determining the auxiliary information according to the size of the resources for data transmission.

[0321] Exemplarily, this step can refer to Figure 13 Step S25 shown in the figure, which will not be elaborated here.

[0322] S46. The second terminal device sends auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0323] In one example, the auxiliary information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0324] Exemplarily, this step can refer toFigure 13 The step S26 shown is not elaborated again.

[0325] S47. The first terminal device determines the resources for data transmission according to the auxiliary information.

[0326] In one example, step S47 specifically includes the following implementation manners:

[0327] The first implementation manner of step S47: Select resources from the resource set indicated by the auxiliary information as the resources for data transmission, where the auxiliary information is used to indicate the unoccupied resource set (or resources).

[0328] In one example, the first implementation manner of step S47 specifically includes: randomly selecting resources from the resource set indicated by the auxiliary information as the resources for data transmission; or, selecting the resource with the highest priority from the resources in the resource set indicated by the auxiliary information as the resources for data transmission.

[0329] The second implementation manner of step S47: Determine the resources for data transmission according to the resource set indicated by the auxiliary information and the detected resource set.

[0330] In one example, the second implementation manner of step S47 specifically includes: determining the common resources between the resource set indicated by the auxiliary information and the detected resource set; selecting resources from the common resources as the resources for data transmission.

[0331] Exemplarily, this step can refer to Figure 13 the step S27 shown and will not be elaborated again.

[0332] S48. The first terminal device sends sidelink control information to the second terminal device.

[0333] Exemplarily, this step can refer to Figure 13 the step S28 shown and will not be elaborated again.

[0334] In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1st stage SCI, or 2nd stage SCI, or SCI.

[0335] Step S48 is an optional step. If step S48 is not executed, it can be stipulated in the protocol that both the first terminal device and the second terminal device have obtained the above necessary information for data reception.

[0336] Among them, the execution order between step S48 and the above steps S41 - S47 is not limited, as long as step S28 is executed before step S49.

[0337] S49. The first terminal device sends data to the second terminal device according to the resources for data transmission.

[0338] Exemplarily, this step can refer to Figure 13 step S29 shown in the figure, which will not be elaborated here.

[0339] In this embodiment, the first terminal device is the data sender, and the second terminal device is the data receiver; the first terminal device sends the first information to the second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information periodically, and the auxiliary information is used to assist the first terminal device in selecting resources for data transmission. For example, the auxiliary information is used to indicate unoccupied resources; furthermore, the resources provided by the second terminal device can be used as a reference for the first terminal device to select resources; the auxiliary information can help the first terminal device exclude the resources occupied by hidden terminal devices, avoid different terminal devices using the same resource to send data, avoid signal collisions and mutual interference during the data transmission process, thereby improving the success rate of the first terminal device in transmitting data to the second terminal device; and, for the case of resource reuse, it can make the resources be reasonably utilized and improve the resource utilization efficiency. And, in order to facilitate the first terminal device to obtain the resources required for each transmission, instead of the first terminal device continuously triggering the second terminal device to return auxiliary information, the method of using the first information to instruct the second terminal device to send auxiliary information periodically is adopted, so that the second terminal device returns auxiliary information periodically, and each returned auxiliary information is used to assist the first terminal device in selecting resources for data transmission; thus, reducing the signaling overhead of the first terminal device. And, the first terminal device sends BSR information to the second terminal device, so that when the second terminal device determines the auxiliary information, it can calculate the resource granularity for listening more reasonably according to the size of the data to be transmitted indicated by the BSR information, and then determine the resources suitable for the first terminal device to perform data transmission, making the resources be reasonably utilized.

[0340] Figure 16 Another signaling diagram of the device - to - device based resource determination method provided by the embodiments of the present application is shown in Figure 16 the figure, and the method includes:

[0341] S51. The first terminal device sends channel state information reference signal configuration information to the second terminal device, where the channel state information reference signal configuration information is used to indicate receiving the channel state information reference signal.

[0342] Exemplarily, in this embodiment, the first terminal device is the sender of data, the second terminal device is the auxiliary device (the second terminal device is not the receiver of data); the third terminal device is the receiver of data. Among them, the second terminal device may or may not have the ability to schedule resources for data transmission, and this is not limited.

[0343] This step can refer to Figure 15 the steps shown in S41 as described above, and will not be elaborated here. Step S51 is an optional step.

[0344] S52. The first terminal device sends a channel state information reference signal to the second terminal device, where the channel state information reference signal is used to determine the channel state information.

[0345] Exemplarily, this step can refer to Figure 15 the steps shown in S42 as described above, and will not be elaborated here. Step S52 is an optional step.

[0346] S53. The first terminal device sends a first piece of information to the second terminal device, where the first piece of information is specifically used to instruct the second terminal device to periodically send auxiliary information.

[0347] In one example, the first indication field or the first bit in the first piece of information is used to indicate the periodic time interval for sending the auxiliary information, and the second indication field or the second bit in the first piece of information is used to indicate the time point for sending the auxiliary information.

[0348] In one example, the first piece of information is physical layer sidelink control information, or media access control layer sidelink control information, or radio resource control layer sidelink control information.

[0349] Exemplarily, before the first terminal device needs to send data to the second terminal device, it first sends the first piece of information to the second terminal device. In this embodiment, the first piece of information can also be referred to as "auxiliary information sending configuration information".

[0350] This step can refer to Figure 15 the steps shown in S43 as described above, and will not be elaborated here.

[0351] S54. The first terminal device sends a buffer status report message to the second terminal device, where the buffer status report message is used to indicate the size of the data to be transmitted.

[0352] In one example, the preset indication field or the scrambled bit in the buffer status report message is used to indicate the size of the data to be transmitted.

[0353] In one example, the buffer status report message is a physical layer sidelink control information, or a MAC layer sidelink control information, or an RRC layer sidelink control information.

[0354] Exemplarily, this step can refer to Figure 15 the shown step S44, which will not be elaborated herein.

[0355] S55. The second terminal device determines auxiliary information according to the buffer status report message, where the auxiliary information is used to indicate the set of unoccupied resources (or resources).

[0356] In one example, the auxiliary information is specifically used to indicate the size and location anchor of the resources for data transmission.

[0357] In one example, step S55 specifically includes the following process: determining the size of the resources for data transmission according to the buffer status report message; and determining the auxiliary information according to the size of the resources for data transmission.

[0358] Exemplarily, this step can refer to Figure 15 the shown step S45, which will not be elaborated herein.

[0359] S56. The second terminal device sends the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0360] In one example, the auxiliary information is a physical layer sidelink control information, or a MAC layer sidelink control information, or an RRC layer sidelink control information.

[0361] Exemplarily, this step can refer to Figure 15 the shown step S46, which will not be elaborated herein.

[0362] S57. The first terminal device determines the resources for data transmission according to the auxiliary information.

[0363] In one example, step S57 specifically includes the following implementation manners:

[0364] The first implementation manner of step S57: Selecting resources from the set of resources indicated by the auxiliary information as the resources for data transmission, where the auxiliary information is used to indicate the set of unoccupied resources (or resources).

[0365] In one example, the first implementation manner of step S57 specifically includes: randomly selecting resources from the set of resources indicated by the auxiliary information as the resources for data transmission; or selecting the resource with the highest priority from the resources in the set of resources indicated by the auxiliary information as the resources for data transmission.

[0366] The second implementation manner of step S57: Determine the resources for data transmission according to the resource set indicated by the auxiliary information and the detected resource set.

[0367] In an example, the second implementation manner of step S57 specifically includes: determining the common resources between the resource set indicated by the auxiliary information and the detected resource set; selecting resources from the common resources as the resources for data transmission.

[0368] Exemplarily, for this step, reference can be made to Figure 15 step S47 shown, but Figure 15 differently, the resources for data transmission determined in step S57 are the resources required when the first terminal device transmits data to the third terminal device.

[0369] S58: The first terminal device sends sidelink control information to the third terminal device.

[0370] Exemplarily, the first terminal device sends sidelink control information to the third terminal device, and the sidelink control information is used to indicate information such as the MCS for data transmission. That is, before the first terminal device transmits data to the third terminal device, the first terminal device indicates necessary information such as the MCS for data reception; then, the first terminal device notifies the third terminal device of the necessary information for data reception through the sidelink control information.

[0371] In an example, the first terminal device uses the resources for data transmission in step S57 to send sidelink control information to the third terminal device.

[0372] In an example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1st stage SCI, or 2nd stage SCI, or SCI.

[0373] Step S58 is an optional step. If step S58 is not executed, it can be stipulated in the protocol that both the first terminal device and the third terminal device already know the above necessary information for data reception.

[0374] Among them, there is no restriction on the execution order between step S58 and the above steps S51 - S57, as long as step S58 is executed before step S59.

[0375] S59: The first terminal device sends data to the third terminal device according to the resources for data transmission.

[0376] Exemplarily, the first terminal device uses the resources obtained in step S57 for data transmission to send data to the third terminal device.

[0377] In this embodiment, the first terminal device is the data sender, the second terminal device is the auxiliary device, and the third terminal device is the data receiver; the first terminal device sends the first information to the second terminal device, and the first information is used to instruct the second terminal device to periodically send auxiliary information, and the auxiliary information is used to assist the first terminal device in selecting resources for data transmission. For example, the auxiliary information is used to indicate the unoccupied resources; furthermore, although the second terminal device is not the data receiver, the resources provided by the second terminal device can be used as a reference for the first terminal device to select resources; the auxiliary information can help the first terminal device exclude the resources occupied by the hidden terminal device, avoid different terminal devices using the same resource to send data, avoid signal collision and mutual interference during data transmission, thereby improving the success rate of the first terminal device transmitting data to the third terminal device; and, for the case of resource reuse, the resources can be reasonably utilized and the resource utilization efficiency can be improved. And, in order to facilitate the first terminal device to obtain the resources required for each transmission, it is not necessary for the first terminal device to continuously trigger the second terminal device to return the auxiliary information. By using the method of using the first information to instruct the second terminal device to periodically send the auxiliary information, the second terminal device periodically returns the auxiliary information, and each returned auxiliary information is used to assist the first terminal device in selecting resources for data transmission; thereby, reducing the signaling overhead of the first terminal device. And, the first terminal device sends the BSR information to the second terminal device, so that when determining the auxiliary information, the second terminal device can more reasonably calculate the resource granularity to be listened according to the size of the data to be transmitted indicated by the BSR information, and then determine the resources suitable for the first terminal device to perform data transmission, so that the resources are reasonably utilized.

[0378] Figure 17 It is a signaling diagram of another device-to-device based resource determination method provided by an embodiment of the present application, as Figure 17 shown, and the method includes:

[0379] S61. The first terminal device sends channel state information reference signal configuration information to the second terminal device, where the channel state information reference signal configuration information is used to indicate receiving the channel state information reference signal.

[0380] Exemplarily, in this embodiment, communication is performed between the first terminal device and the second terminal device. The first terminal device is the data sender, the second terminal device is the data receiver, and the second terminal device is the auxiliary device. Among them, the second terminal device may or may not have the ability to schedule resources for data transmission, and this is not limited.

[0381] This step can be referred to Figure 13 to the step S21 shown, which will not be elaborated here. Step S61 is an optional step.

[0382] S62. The first terminal device sends a channel state information reference signal to the second terminal device, where the channel state information reference signal is used to determine the channel state information.

[0383] Exemplarily, this step can be referred to Figure 13 to the step S22 shown, which will not be elaborated here. Step S62 is an optional step.

[0384] S63. The first terminal device sends first information to the second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information; the first information is also used to instruct a buffer status report message, and the buffer status report message is used to indicate the size of the data to be transmitted.

[0385] In one example, a preset indication field or a preset bit in the first information is used to instruct the second terminal device to send auxiliary information. Another preset indication field or another preset bit in the first information is used to indicate the size of the data to be transmitted.

[0386] In one example, the first information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

[0387] Exemplarily, before the first terminal device needs to send data to the second terminal device, it first sends the first information to the second terminal device.

[0388] The first information is used to instruct the second terminal device to send auxiliary information, and the auxiliary information is used to assist the first terminal device in resource selection for data transmission.

[0389] Moreover, in order to facilitate the second terminal device to determine appropriate resources for the first terminal device, the first information needs to indicate the size of the data to be transmitted by the first terminal device. For example, the first information includes an index of the size of the data to be transmitted in the buffer, or the first information includes the size of the data to be transmitted in the buffer; that is, the "size of the data to be transmitted" refers to the index of the size of the data to be transmitted in the buffer, or refers to the size of the data to be transmitted in the buffer.

[0390] The first information has multiple indication fields. One of the preset indication fields among the multiple indication fields can be used for the second terminal device to send auxiliary information; another preset indication field among the multiple indication fields can be used to indicate the size of the data to be transmitted. Wherein, the position of the preset indication field in the first information and the size of the preset indication field are not limited. Alternatively, the first information has multiple bits. One of the preset bits among the multiple bits can be used for the second terminal device to send auxiliary information; another preset bit among the multiple bits can be used to indicate the size of the data to be transmitted. Wherein, the position of the preset bit in the first information and the size of the preset indication field are not limited.

[0391] In one example, the first terminal device sends the first information to the second terminal device, and the first information is a separate signaling. One of the preset indication fields in the first information is used to indicate that the second terminal device sends auxiliary information, and another preset indication field in the first information is used to indicate the size of the data to be transmitted. Alternatively, one of the preset bits in the first information is used to indicate that the second terminal device sends auxiliary information, and another preset bit in the first information is used to indicate the size of the data to be transmitted. Alternatively, one of the preset indication fields in the first information is used to indicate that the second terminal device sends auxiliary information, and another preset bit in the first information is used to indicate the size of the data to be transmitted. Alternatively, one of the preset bits in the first information is used to indicate the size of the data to be transmitted, and another preset indication field in the first information is used to indicate the size of the data to be transmitted.

[0392] In another example, the first information is physical layer sidelink control information; the preset indication field or the preset bit in the physical layer sidelink control information is used to indicate that the second terminal device sends auxiliary information, and another preset indication field or another preset bit in the physical layer sidelink control information is used to indicate the size of the data to be transmitted. Wherein, the physical layer sidelink control information can indicate that the second terminal device sends auxiliary information and indicate the size of the data to be transmitted in an explicit or implicit manner. For example, the physical layer sidelink control information can be 1 st stage SCI, or 2 nd stage SCI, or SCI.

[0393] For example, the first information is 2 nd stage SCI. 2 ndThere is a preset indication field in the stage SCI; when the value in this preset indication field is the first value, it represents activating the second terminal device to send auxiliary information to the first terminal device; when the value in this preset indication field is the second value, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device, and "deactivating" means that the second terminal device does not need to send auxiliary information, and the first value and the second value are different. Also, 2 nd There is another preset indication field in the stage SCI; this other preset indication field is used to indicate the size of the data to be transmitted; for example, 2 nd Another preset indication field in the stage SCI includes a 5-bit buffer size field, and this 5-bit buffer size field represents the size of the data to be transmitted. Also, 2 nd The stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, that is, 2 nd The stage SCI includes the sending 2 nd identifier of the terminal device of the stage SCI, and the receiving 2 nd identifier of the terminal device of the stage SCI; so that the second terminal device knows that it is the first terminal device sending the first information to itself.

[0394] For example, the first information is 1 st the stage SCI. 1 st There is a preset indication field in the stage SCI; when the value in this preset indication field is the first value, it represents activating the second terminal device to send auxiliary information to the first terminal device; when the value in this preset indication field is the second value, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device, and "deactivating" means that the second terminal device does not need to send auxiliary information, and the first value and the second value are different. Also, 1 st There is another preset indication field in the stage SCI; this other preset indication field is used to indicate the size of the data to be transmitted; for example, 1 st Another preset indication field in the stage SCI includes a 5-bit buffer size field, and this 5-bit buffer size field represents the size of the data to be transmitted. Also, the second terminal device receives 1 st before receiving the stage SCI or after receiving 1 st the stage SCI, the second terminal device also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identification information is 2 nd the stageSCI; thus, the second terminal device knows that it is the first terminal device sending the first information to itself.

[0395] For example, the first piece of information is 2 nd stage SCI. 2 nd There is a preset bit in stage SCI; when the preset bit is the first bit sequence, it indicates activating the second terminal device to send auxiliary information to the first terminal device, and the first bit sequence includes at least one bit; when the preset bit is the second bit sequence, it indicates deactivating the second terminal device from sending auxiliary information to the first terminal device, and "deactivating" means that the second terminal device does not need to send auxiliary information, and the second bit sequence includes at least one bit; the first bit sequence and the second bit sequence are different bit sequences. And, 2 nd There is another preset bit in stage SCI; the other preset bit is used to indicate the size of the data to be transmitted. For example, x-bit scrambling is performed on the CRC of the 2nd stage SCI to indicate the size of the data to be transmitted, where x is a positive integer. And, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, 2 nd stage SCI includes sending 2 nd the identifier of the terminal device of stage SCI, and receiving 2 nd the identifier of the terminal device of stage SCI, so that the second terminal device knows that it is the first terminal device that is sending the first piece of information to itself.

[0396] For example, the first terminal device sends 2 nd stage SCI, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; 2 nd There is a CRC in stage SCI. At this time, 1-bit scrambling is performed on 2 nd the last bit of the CRC of stage SCI; scrambling with 1 indicates activating the second terminal device to send auxiliary information to the first terminal device, and scrambling with 0 indicates deactivating the second terminal device from sending auxiliary information to the first terminal device; and, 1-bit scrambling is performed on 2 nd the 4th to the mth bits from the bottom of the CRC of stage SCI, which is used to indicate the size of the data to be transmitted, and m is a positive integer greater than or equal to 4.

[0397] For example, the first piece of information is 1 st stage SCI. 1 stThere is a preset bit in the stage SCI; when the preset bit is the first bit sequence, it indicates activating the second terminal device to send auxiliary information to the first terminal device, and the first bit sequence includes at least one bit; when the preset bit is the second bit sequence, it indicates deactivating the second terminal device from sending auxiliary information to the first terminal device, and "deactivating" means that the second terminal device does not need to send auxiliary information, and the second bit sequence includes at least one bit; the first bit sequence and the second bit sequence are different bit sequences. And, 1 st There is another preset bit in the stage SCI; the other preset bit is used to indicate the size of the data to be transmitted. For example, use x-bit scrambling on 1 st the CRC of the stage SCI to indicate the size of the data to be transmitted, where x is a positive integer. And, the second terminal device receives 1 st before the stage SCI or receives 1 st after the stage SCI, and also receives the identification information sent by the first terminal device, and the identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd the stage SCI; thus, the second terminal device knows that it is the first terminal device that is sending the first information to itself.

[0398] For example, the first terminal device sends 1 st the stage SCI and 2 nd the stage SCI; 1 st There is a CRC in the stage SCI. At this time, use 1-bit scrambling on 1 st the last bit of the CRC of the stage SCI; using 1 for scrambling means activating the second terminal device to send auxiliary information to the first terminal device, and using 0 for scrambling means deactivating the second terminal device from sending auxiliary information to the first terminal device; and, use 1-bit scrambling on 1 st the 4th to the mth bits from the bottom of the CRC of the stage SCI to indicate the size of the data to be transmitted, where m is a positive integer greater than or equal to 4; 2 nd The stage SCI is used to indicate the identification of the first terminal device and the identification of the second terminal device.

[0399] In another example, the first information is MAC layer sidelink control information; a preset indication field or a preset bit in the MAC layer sidelink control information is used to indicate that the second terminal device sends auxiliary information, and another preset indication field or another preset bit in the MAC layer sidelink control information is used to indicate the size of the data to be transmitted. Among them, the MAC layer sidelink control information can indicate that the second terminal device sends auxiliary information and indicate the size of the data to be transmitted in an explicit or implicit manner. For example, the MAC layer sidelink control information can be SL MAC CE information.

[0400] For example, the first information is SL MAC CE information. There is a preset indication field in the SL MAC CE information; when the value in the one preset indication field is the first value, it represents activating the second terminal device to send auxiliary information to the first terminal device; when the value in the one preset indication field is the second value, it represents deactivating the second terminal device from sending auxiliary information to the first terminal device, and "deactivating" means that the second terminal device does not need to send auxiliary information, and the first value and the second value are different. And, there is another preset indication field in the SL MAC CE information, and the another preset indication field is used to indicate the size of the data to be transmitted; for example, the preset indication field in the SL MAC CE information includes a 5-bit buffer size field, and the 5-bit buffer size field represents the size of the data to be transmitted. And, before or after the second terminal device receives the SL MAC CE information, it also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that sends the first information to itself.

[0401] In yet another example, the first information is RRC layer sidelink control information; a preset indication field or a preset bit in the RRC layer sidelink control information is used to indicate that the second terminal device sends auxiliary information, and another preset indication field or another preset bit in the RRC layer sidelink control information is used to indicate the size of the data to be transmitted. Among them, the RRC layer sidelink control information can indicate that the second terminal device sends auxiliary information and indicate the size of the data to be transmitted in an explicit or implicit manner. For example, the RRC layer sidelink control information can be PC5 RRC information.

[0402] For example, the first piece of information is the PC5 RRC information. There is a preset indication field in the PC5 RRC information; when the value in this preset indication field is the first value, it indicates activating the second terminal device to send auxiliary information to the first terminal device; when the value in this preset indication field is the second value, it indicates deactivating the second terminal device from sending auxiliary information to the first terminal device, and "deactivating" means that the second terminal device does not need to send auxiliary information, and the first value and the second value are different. Also, there is another preset indication field in the PC5 RRC information; this other preset indication field is used to indicate the size of the data to be transmitted; for example, the preset indication field in the PC5 RRC information includes a 5-bit buffer size field, and this 5-bit buffer size field represents the size of the data to be transmitted. Also, before or after receiving the PC5 RRC information, the second terminal device also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that sends the first piece of information to itself.

[0403] Among them, for steps S61, S62, and S63, there is no requirement for the execution order among these three steps.

[0404] S64. The second terminal device determines auxiliary information according to the buffer status report message indicated by the first piece of information, and the auxiliary information is used to indicate the set of unoccupied resources (or resources).

[0405] In one example, the auxiliary information is specifically used to indicate the size and location anchor of the resources for data transmission.

[0406] In one example, step S64 specifically includes the following process: determining the size of the resources for data transmission according to the buffer status report message; and determining the auxiliary information according to the size of the resources for data transmission.

[0407] Exemplarily, after receiving the first piece of information, the second terminal device determines that it needs to return auxiliary information to the first terminal device according to the first piece of information; however, before returning the auxiliary information, it needs to first determine the auxiliary information. The second terminal device determines the auxiliary information according to the BSR message indicated by the first piece of information.

[0408] Among them, for the method of determining the auxiliary information, reference can be made to Figure 13 step S25 of, which will not be elaborated here.

[0409] S65. The second terminal device sends the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0410] In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0411] Exemplarily, this step may refer to Figure 13 step S26 in, which will not be elaborated here.

[0412] S66. The first terminal device determines the resources for data transmission according to the sidelink control information.

[0413] In one example, step S27 specifically includes the following implementation manners:

[0414] The first implementation manner of step S66: Select resources from the resource set indicated by the sidelink control information as the resources for data transmission, where the sidelink control information is used to indicate the unoccupied resource set (or resources).

[0415] In one example, the first implementation manner of step S66 specifically includes: randomly selecting resources from the resource set indicated by the sidelink control information as the resources for data transmission; or selecting the resource with the highest priority from the resources in the resource set indicated by the sidelink control information as the resources for data transmission.

[0416] The second implementation manner of step S66: Determine the resources for data transmission according to the resource set indicated by the sidelink control information and the detected resource set.

[0417] In one example, the second implementation manner of step S66 specifically includes: determining the common resources between the resource set indicated by the sidelink control information and the detected resource set; selecting resources from the common resources as the resources for data transmission.

[0418] Exemplarily, this step may refer to Figure 13 step S27 in, which will not be elaborated here.

[0419] S67. The first terminal device sends sidelink control information to the second terminal device.

[0420] Exemplarily, the first terminal device uses the resources for data transmission in step S66 to send sidelink control information to the second terminal device. In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1st stage SCI, or 2nd stage SCI, or SCI. This step may refer to Figure 13 step S28 in, which will not be elaborated here.

[0421] Step S67 is an optional step. If step S67 is not executed, it can be stipulated in the protocol that both the first terminal device and the second terminal device have learned the above necessary information for data reception.

[0422] Among them, the execution order between step S67 and the above steps S61 - S66 is not limited, as long as step S67 is executed before step S68.

[0423] S68. The first terminal device sends data to the second terminal device according to the resources for data transmission.

[0424] Exemplarily, the first terminal device uses the resources for data transmission obtained in step S66 to send data to the second terminal device.

[0425] This embodiment, compared with Figure 13 the embodiment shown, is different in that Figure 13 in that embodiment, the first terminal device sends an assistance request and BSR information to the second terminal device; in this embodiment, the first terminal sends a first message to the second terminal device, where the first message is used to instruct the second terminal device to send assistance information, and the first message is also used to indicate the size of the data to be transmitted. Thus, in addition to having the Figure 13 technical effects of the embodiment shown, this embodiment can also instruct the second terminal device to send assistance information and indicate the size of the data to be transmitted through one signaling, thereby saving signaling overhead.

[0426] Figure 18 Another signaling diagram of the device - to - device - based resource determination method provided by the embodiment of the present application is as shown in Figure 18 and the method includes:

[0427] S71. The first terminal device sends channel state information reference signal configuration information to the second terminal device, where the channel state information reference signal configuration information is used to indicate receiving the channel state information reference signal.

[0428] Exemplarily, in this embodiment, the first terminal device is the data sender, the second terminal device is the assistance side (the second terminal device is not the data receiver); the third terminal device is the data receiver. Among them, the second terminal device may or may not have the ability to schedule resources for data transmission, and this is not limited.

[0429] This step can refer to Figure 14 step S31 shown and will not be elaborated here. Step S71 is an optional step.

[0430] S72. The first terminal device sends a channel state information reference signal to the second terminal device, where the channel state information reference signal is used to determine the channel state information.

[0431] Exemplarily, for this step, reference can be made to Figure 14 step S32 shown in the figure, which will not be elaborated here. Step S72 is an optional step.

[0432] S73. The first terminal device sends first information to the second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information; the first information is also used to instruct a buffer status report message, and the buffer status report message is used to indicate the size of the data to be transmitted.

[0433] In one example, a preset indication field or a preset bit in the first information is used to instruct the second terminal device to send auxiliary information. Another preset indication field or another preset bit in the first information is used to indicate the size of the data to be transmitted.

[0434] In one example, the first information is a physical layer sidelink control information, or a medium access control layer sidelink control information, or a radio resource control layer sidelink control information.

[0435] Exemplarily, for this step, reference can be made to Figure 16 step S63 shown in the figure, which will not be elaborated here.

[0436] S74. The second terminal device determines auxiliary information according to the buffer status report message indicated by the first information, where the auxiliary information is used to indicate a set of unoccupied resources (or resources).

[0437] Exemplarily, for this step, reference can be made to Figure 16 step S64 shown in the figure, which will not be elaborated here.

[0438] S75. The second terminal device sends the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0439] Exemplarily, for this step, reference can be made to Figure 14 step S36 shown in the figure, which will not be elaborated here.

[0440] S76. The first terminal device determines resources for data transmission according to the auxiliary information.

[0441] Exemplarily, for this step, reference can be made to Figure 14 step S37 shown in the figure, which will not be elaborated here.

[0442] S77. The first terminal device sends sidelink control information to the third terminal device.

[0443] Exemplarily, the first terminal device uses the resources for data transmission in step S76 to send sidelink control information to the third terminal device. In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1st stage SCI, or 2nd stage SCI, or SCI. This step can refer to Figure 14 the steps shown in step S38, which will not be elaborated here.

[0444] Step S38 is an optional step. Moreover, there is no restriction on the execution order between step S77 and the above steps S71 - S76, as long as step S77 is executed before step S78.

[0445] S78. The first terminal device sends data to the third terminal device according to the resources for data transmission.

[0446] Exemplarily, the first terminal device uses the resources for data transmission obtained in step S76 to send data to the third terminal device. This step can refer to Figure 14 the steps shown in step S39, which will not be elaborated here.

[0447] This embodiment is different from Figure 14 the embodiment shown in that Figure 14 in that embodiment, the first terminal device sends an assistance request and BSR information to the second terminal device; in this embodiment, the first terminal sends a first message to the second terminal device, where the first message is used to instruct the second terminal device to send assistance information, and the first message is also used to indicate the size of the data to be transmitted. Thus, in addition to having the Figure 14 technical effects of the embodiment shown, this embodiment can also instruct the second terminal device to send assistance information and indicate the size of the data to be transmitted through one signaling, thereby saving signaling overhead.

[0448] Figure 19 Another signaling diagram of the device - to - device based resource determination method provided by the embodiments of this application is shown in Figure 19 and the method includes:

[0449] S81. The first terminal device sends channel state information reference signal configuration information to the second terminal device, where the channel state information reference signal configuration information is used to indicate receiving the channel state information reference signal.

[0450] Exemplarily, in this embodiment, communication is performed between a first terminal device and a second terminal device. The first terminal device is the data sender, and the second terminal device is the data receiver, and the second terminal device is the auxiliary device. Among them, the second terminal device may not have the ability to schedule resources for data transmission, or may have the ability to schedule resources for data transmission, which is not limited herein.

[0451] This step can refer to Figure 15 step S41 shown in the figure, which will not be elaborated herein. Step S81 is an optional step.

[0452] S82. The first terminal device sends a channel state information reference signal to the second terminal device, where the channel state information reference signal is used to determine the channel state information.

[0453] Exemplarily, this step can refer to Figure 15 step S42 shown in the figure, which will not be elaborated herein. Step S82 is an optional step.

[0454] S83. The first terminal device sends a first piece of information to the second terminal device, where the first piece of information is used to instruct the second terminal device to periodically send auxiliary information; the first piece of information is also used to instruct a buffer status report message, and the buffer status report message is used to indicate the size of the data to be transmitted.

[0455] In one example, a preset indication field or a preset bit in the first piece of information is used to instruct the second terminal device to periodically send auxiliary information. Another preset indication field or another preset bit in the first piece of information is used to indicate the size of the data to be transmitted.

[0456] In one example, the first piece of information is a physical layer sidelink control information, or a medium access control layer sidelink control information, or a radio resource control layer sidelink control information.

[0457] Exemplarily, before the first terminal device needs to send data to the second terminal device, it first sends the first piece of information to the second terminal device.

[0458] This first piece of information is used to instruct the second terminal device to periodically send auxiliary information, and the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0459] Moreover, to facilitate the second terminal device in determining appropriate resources for the first terminal device, the first information needs to indicate the size of the data to be transmitted by the first terminal device. For example, the first information includes an index of the size of the data to be transmitted in the buffer, or the first information includes the size of the data to be transmitted in the buffer; that is, the "size of the data to be transmitted" refers to the index of the size of the data to be transmitted in the buffer, or refers to the size of the data to be transmitted in the buffer.

[0460] In one example, the first information has multiple indication fields. One first indication field among the multiple indication fields can be used to indicate the periodic time interval for sending the auxiliary information; one second indication field among the multiple indication fields can be used to indicate the time point for sending the auxiliary information; one third indication field among the multiple indication fields is used to indicate the size of the data to be transmitted by the first terminal device. Among them, the position and size of the first indication field in the first information, the position and size of the second indication field in the first information, and the position and size of the third indication field in the first information are not limited.

[0461] Alternatively, the first information has multiple bits. One first bit among the multiple bits can be used to indicate the periodic time interval for sending the auxiliary information; one second bit among the multiple bits can be used to indicate the time point for sending the auxiliary information; one third bit among the multiple bits is used to indicate the size of the data to be transmitted by the first terminal device. Among them, the position and size of the first bit in the first information, the position and size of the second bit in the first information, and the position and size of the third bit in the first information are not limited.

[0462] In one example, the "periodic time interval for sending the auxiliary information" can be the actual time interval for sending the auxiliary information; or, the "periodic time interval for sending the auxiliary information" can be an index of the actual time interval for sending the auxiliary information. In this case, an index table between the actual time interval and the index needs to be established.

[0463] In one example, the "time point for sending the auxiliary information" can be an absolute time, or can be a relative time.

[0464] The "periodic time interval for sending the auxiliary information" and the "time point for sending the auxiliary information" can refer to Figure 15 the introduction in step S43 of

[0465] In one example, a first terminal device sends first information to a second terminal device. The first information is a single signaling. A preset indication field or a preset bit in the first information is used to indicate that the second terminal device periodically sends auxiliary information; another preset indication field or another preset bit in the first information is used to indicate the size of the data to be transmitted. For example, a first indication field in the first information is used to indicate the periodic time interval for sending the auxiliary information; a second indication field in the first information is used to indicate the time point for sending the auxiliary information; a third indication field in the first information is used to indicate the size of the data to be transmitted.

[0466] In another example, the first information is physical layer sidelink control information; a preset indication field or a preset bit in the physical layer sidelink control information is used to indicate that the second terminal device periodically sends auxiliary information, and another preset indication field or another preset bit in the physical layer sidelink control information is used to indicate the size of the data to be transmitted. The physical layer sidelink control information can indicate that the second terminal device periodically sends auxiliary information and indicate the size of the data to be transmitted in an explicit or implicit manner. For example, the physical layer sidelink control information can be 1 st stage SCI, or 2 nd stage SCI, or SCI.

[0467] For example, the first information is 2 nd stage SCI, and there are a first indication field, a second indication field, and a third indication field in 2 nd stage SCI. The first indication field is used to indicate the periodic time interval for sending the auxiliary information, the second indication field is used to indicate the time point for sending the auxiliary information, and the third indication field is used to indicate the size of the data to be transmitted. The values in the first indication field, the second indication field, and the third indication field can be represented by integers or by strings, and this is not limited. Also, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; thus, the second terminal device can know that it is the first terminal device that sends the first information to itself.

[0468] For example, the first information is 1 st stage SCI, 1 stIn stage SCI, there are a first indication field, a second indication field, and a third indication field. The first indication field is used to indicate the periodic time interval for sending auxiliary information. The second indication field is used to indicate the time point for sending auxiliary information. The third indication field is used to indicate the size of the data to be transmitted. The values in the first indication field, the second indication field, and the third indication field can be represented by integers or by strings, and there is no limitation on this. Also, the second terminal device receives 1 st before receiving stage SCI or receives 1 st after receiving stage SCI, and also receives the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device. For example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that sends the first information to itself.

[0469] For example, the first information is 2 nd stage SCI, 2 nd In stage SCI, there are a first bit, a second bit, and a third bit. The first bit is used to indicate the periodic time interval for sending auxiliary information. The second bit is used to indicate the time point for sending auxiliary information. The third bit is used to indicate the size of the data to be transmitted. The values in the first bit, the second bit, and the third bit can be represented by integers or by strings, and there is no limitation on this. Also, 2 nd stage SCI itself includes the identification of the first terminal device and the identification of the second terminal device; thus, the second terminal device can know that it is the first terminal device that sends the first information to itself.

[0470] For example, the first information is 1 st stage SCI, 1 st In stage SCI, there are a first bit, a second bit, and a third bit. The first bit is used to indicate the periodic time interval for sending auxiliary information. The second bit is used to indicate the time point for sending auxiliary information. The third bit is used to indicate the size of the data to be transmitted. The values in the first bit, the second bit, and the third bit can be represented by integers or by strings, and there is no limitation on this. Also, the second terminal device receives 1 st before receiving stage SCI or receives 1 st after receiving stage SCI, and also receives the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device. For example, the identification information is 2 ndstage SCI; thus, the second terminal device can know that it is the first terminal device that sends the first information to itself.

[0471] In another example, the first information is MAC layer sidelink control information; a preset indication field or a preset bit in the MAC layer sidelink control information is used to indicate that the second terminal device periodically sends auxiliary information, and another preset indication field or another preset bit in the MAC layer sidelink control information is used to indicate the size of the data to be transmitted. Among them, the MAC layer sidelink control information can indicate that the second terminal device periodically sends auxiliary information and indicate the size of the data to be transmitted in an explicit or implicit manner. For example, the MAC layer sidelink control information can be SL MAC CE information.

[0472] For example, the first information is SL MAC CE information. There are a first indication field, a second indication field and a third indication field in the SL MAC CE information. The first indication field is used to indicate the periodic time interval for sending the auxiliary information, the second indication field is used to indicate the time point for sending the auxiliary information, and the third indication field is used to indicate the size of the data to be transmitted. The values in the first indication field, the second indication field and the third indication field can be represented by integers or strings, and there is no limit to this. Also, before or after receiving the SL MAC CE, the second terminal device also needs to receive the identification information sent by the first terminal device. The identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that sends the first information to itself.

[0473] In yet another example, the first information is RRC layer sidelink control information; a preset indication field or a preset bit in the RRC layer sidelink control information is used to indicate that the second terminal device periodically sends auxiliary information, and another preset indication field or another preset bit in the RRC layer sidelink control information is used to indicate the size of the data to be transmitted. Among them, the RRC layer sidelink control information can indicate that the second terminal device periodically sends auxiliary information and indicate the size of the data to be transmitted in an explicit or implicit manner. For example, the RRC layer sidelink control information can be PC5 RRC information.

[0474] For example, the first information is PC5 RRC information; there are a first indication field, a second indication field, and a third indication field in the PC5 RRC information. The first indication field is used to indicate the periodic time interval for sending the auxiliary information, the second indication field is used to indicate the time point for sending the auxiliary information, and the third indication field is used to indicate the size of the data to be transmitted. The values in the first indication field, the second indication field, and the third indication field can be represented by integers or by strings, and there is no limitation on this. Moreover, before or after receiving the SL MAC CE, the second terminal device also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identification of the first terminal device and the identification of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can know that it is the first terminal device that sends the first information to itself.

[0475] S84. The second terminal device determines auxiliary information according to the buffer status report message indicated by the first information, and the auxiliary information is used to indicate the set of unoccupied resources (or resources).

[0476] In one example, the auxiliary information is specifically used to indicate the size and location anchor of the resources for data transmission.

[0477] In one example, step S55 specifically includes the following process: determining the size of the resources for data transmission according to the buffer status report message; determining the auxiliary information according to the size of the resources for data transmission.

[0478] Exemplarily, after receiving the first information, the second terminal device determines that it needs to return auxiliary information to the first terminal device according to the first information; however, before returning the auxiliary information, it is necessary to first determine the auxiliary information. The second terminal device determines the auxiliary information according to the BSR message indicated by the first information.

[0479] Among them, for the method of determining the auxiliary information, reference can be made to Figure 15 step S45 of, which will not be elaborated here.

[0480] S85. The second terminal device sends the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0481] In one example, the auxiliary information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0482] Exemplarily, this step can refer to Figure 15 step S46 of, which will not be elaborated here.

[0483] S86. The first terminal device determines the resources for data transmission according to the auxiliary information.

[0484] Exemplarily, for this step, reference can be made to Figure 15 step S47 and details are not repeated here.

[0485] S87. The first terminal device sends sidelink control information to the second terminal device.

[0486] Exemplarily, the first terminal device uses the resources for data transmission in step S86 to send sidelink control information to the second terminal device. In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1 st stage SCI, or 2nd stage SCI, or SCI. For this step, reference can be made to Figure 15 step S48 and details are not repeated here.

[0487] Step S87 is an optional step. If step S87 is not executed, it can be stipulated in the protocol that both the first terminal device and the second terminal device have learned the above necessary information for data reception.

[0488] Among them, there is no restriction on the execution order between step S87 and the above steps S81 - S86, as long as step S87 is executed before step S88.

[0489] S88. The first terminal device sends data to the second terminal device according to the resources for data transmission.

[0490] Exemplarily, the first terminal device uses the resources for data transmission obtained in step S86 to send data to the second terminal device. For this step, reference can be made to Figure 15 the step S49 shown and details are not repeated here.

[0491] This embodiment is different from the Figure 15 embodiment shown in that Figure 15 in that embodiment, the first terminal device sends auxiliary information sending configuration information and BSR information to the second terminal device; in this embodiment, the first terminal sends the first information to the second terminal device, where the first information is used to instruct the second terminal device to periodically send auxiliary information, and the first information is also used to indicate the size of the data to be transmitted. Thus, in addition to having the Figure 15 technical effects of the embodiment shown, this embodiment can also use one signaling to instruct the second terminal device to periodically send auxiliary information and indicate the size of the data to be transmitted, thereby saving signaling overhead.

[0492] Figure 20Another signaling diagram of a device-to-device based resource determination method provided by an embodiment of the present application, as Figure 20 shown, the method includes:

[0493] S91. The first terminal device sends channel state information reference signal configuration information to the second terminal device, where the channel state information reference signal configuration information is used to indicate receiving the channel state information reference signal.

[0494] Exemplarily, in this embodiment, the first terminal device is the data sender, the second terminal device is the auxiliary device (the second terminal device is not the data receiver); the third terminal device is the data receiver. Among them, the second terminal device may or may not have the ability to schedule resources for data transmission, and this is not limited.

[0495] This step can refer to Figure 16 the step S51 shown, and will not be elaborated. Step S91 is an optional step.

[0496] S92. The first terminal device sends a channel state information reference signal to the second terminal device, where the channel state information reference signal is used to determine the channel state information.

[0497] Exemplarily, this step can refer to Figure 16 the step S52 shown, and will not be elaborated. Step S92 is an optional step.

[0498] S93. The first terminal device sends the first information to the second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information periodically; the first information is also used to instruct a buffer status report message, and the buffer status report message is used to indicate the size of the data to be transmitted.

[0499] In one example, a preset indication field or a preset bit in the first information is used to instruct the second terminal device to send auxiliary information periodically. Another preset indication field or another preset bit in the first information is used to indicate the size of the data to be transmitted.

[0500] In one example, the first information is a physical layer sidelink control information, or a medium access control layer sidelink control information, or a radio resource control layer sidelink control information.

[0501] Exemplarily, this step can refer to Figure 19 the step S83 shown, and will not be elaborated.

[0502] S94. The second terminal device determines auxiliary information according to the buffer status report message indicated by the first information, and the auxiliary information is used to indicate the set of unoccupied resources (or resources).

[0503] In one example, the auxiliary information is specifically used to indicate the size and location anchor of the resource for data transmission.

[0504] Exemplarily, this step can refer to Figure 19 step S84 shown in the figure, which will not be elaborated here.

[0505] S95. The second terminal device sends auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting a resource for data transmission.

[0506] In one example, the auxiliary information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0507] Exemplarily, this step can refer to Figure 16 step S56 in the figure, which will not be elaborated here.

[0508] S96. The first terminal device determines a resource for data transmission according to the auxiliary information.

[0509] Exemplarily, this step can refer to Figure 16 step S57 in the figure, which will not be elaborated here.

[0510] S97. The first terminal device sends sidelink control information to the third terminal device.

[0511] Exemplarily, the first terminal device uses the resource for data transmission in step S96 to send sidelink control information to the second terminal device. In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1st stage SCI, or 2nd stage SCI, or SCI. This step can refer to Figure 16 step S58 in the figure, which will not be elaborated here.

[0512] Step S97 is an optional step. If step S97 is not executed, it can be stipulated in the protocol that both the first terminal device and the third terminal device have obtained the above necessary information for data reception.

[0513] Among them, the execution order between step S97 and the above steps S91 - S96 is not limited, as long as step S97 is executed before step S98.

[0514] S98. The first terminal device sends data to the third terminal device according to the resource for data transmission.

[0515] Exemplarily, the first terminal device uses the resources obtained in step S96 for data transmission to send data to the second terminal device. For this step, reference can be made to Figure 16 step S59 thereof, which will not be elaborated herein.

[0516] In this embodiment, the difference from the Figure 16 embodiment shown is that Figure 16 in that embodiment, the first terminal device sends auxiliary information sending configuration information and BSR information to the second terminal device; in this embodiment, the first terminal sends the first information to the second terminal device, where the first information is used to instruct the second terminal device to periodically send auxiliary information, and the first information is further used to indicate the size of the data to be transmitted. Therefore, in addition to having the Figure 15 technical effects of the embodiment shown, this embodiment can also instruct the second terminal device to periodically send auxiliary information and indicate the size of the data to be transmitted through one signaling, thereby saving signaling overhead.

[0517] Figure 21 As shown in Figure 21 , this is a schematic flowchart of another device-to-device based resource determination method provided by an embodiment of the present application, and the method includes:

[0518] S201. Send the first information to the second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information.

[0519] S202. Receive the auxiliary information sent by the second terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

[0520] S203. Determine the resources for data transmission according to the auxiliary information.

[0521] In this embodiment, the execution subject of this embodiment may be the first terminal device. For the steps of this embodiment, reference can be made to the Figures 9 - 20 process thereof, which will not be elaborated herein.

[0522] In one example, a preset indication field or a preset bit in the first information is used to instruct the second terminal device to send auxiliary information.

[0523] Alternatively, the first information is specifically used to instruct the second terminal device to periodically send auxiliary information. In one example, a first indication field or a first bit in the first information is used to indicate the periodic time interval for sending the auxiliary information, and a second indication field or a second bit in the first information is used to indicate the time point for sending the auxiliary information.

[0524] In one example, the first information is a physical layer sidelink control information, or a media access control layer sidelink control information, or a radio resource control layer sidelink control information.

[0525] In one example, in step S202, the following may also be performed: sending a buffer status report message to a second terminal device, where the buffer status report message is used to indicate the size of the data to be transmitted. In one example, a preset indication field or scrambled bits in the buffer status report message are used to indicate the size of the data to be transmitted. In one example, the buffer status report message is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

[0526] Alternatively, the first information is also used to indicate a buffer status report message, where the buffer status report message is used to indicate the size of the data to be transmitted.

[0527] In one example, the auxiliary information is specifically used to indicate the size and location anchor of the resources for data transmission.

[0528] In one example, the auxiliary information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

[0529] In one example, step S203 includes:

[0530] Selecting a resource from the resource set indicated by the auxiliary information as the resource for data transmission, where the auxiliary information is used to indicate an unoccupied resource set (or resources); or determining the resource for data transmission according to the resource set indicated by the auxiliary information and the detected resource set.

[0531] In one example, selecting a resource from the resource set indicated by the auxiliary information as the resource for data transmission includes:

[0532] Randomly selecting a resource from the resource set indicated by the auxiliary information as the resource for data transmission; or selecting the resource with the highest priority from the resources in the resource set indicated by the auxiliary information as the resource for data transmission.

[0533] In one example, determining the resource for data transmission according to the resource set indicated by the auxiliary information and the detected resource set includes:

[0534] Determining the common resources between the resource set indicated by the auxiliary information and the detected resource set; and selecting a resource from the common resources as the resource for data transmission.

[0535] In one example, after step S203, the following may also be performed: sending data to the second terminal device or the third terminal device according to the resource for data transmission.

[0536] In this embodiment, for each step of this embodiment, reference may be made to Figures 9 - 20 the process, where the technical process and technical effects are the same and will not be elaborated here.

[0537] Figure 22 FIG. is a schematic flowchart of another device-to-device based resource determination method provided by an embodiment of the present application. As Figure 22 shown, the method includes:

[0538] S301. Determine the resources for data transmission.

[0539] Exemplarily, the execution subject of the method provided in this embodiment may be a second terminal device. Communication is performed between the second terminal device and the first terminal device.

[0540] The first terminal device is the data sender, the second terminal device is the data receiver, and the second terminal device is the scheduling end. Alternatively, the first terminal device is the data sender, the second terminal device is not the data receiver, and the second terminal device is the scheduling end.

[0541] Herein, the "scheduling end" refers to a device that schedules (or is called "allocates") resources or a resource set for other terminal devices; the resources or resource set scheduled for other terminal devices are used for data transmission by other terminal devices. It can be seen that the "scheduling end" has the ability to schedule resources.

[0542] In this embodiment, if the second terminal device is the scheduling end, the second terminal device schedules resources or a resource set for the first terminal device; and the resources or resource set scheduled for the first terminal device are used for data transmission by the first terminal device.

[0543] When the first terminal device needs to send data, the second terminal device determines the resources for data transmission for the first terminal device, including the following several methods.

[0544] In one example, the second terminal device may obtain channel state information, and then determine the resource size according to the channel state information. The second terminal device listens at the granularity of the resource size; the second terminal device determines the resources scheduled for the first terminal device from the resources or resource set obtained by the second terminal device through listening. The second terminal device may determine the data transmission resources for scheduling other terminal devices from the resources or resource set obtained by the second terminal device through listening. The resources or resource set obtained by the second terminal device through listening may be a resource pool, or a scheduling resource pool. That is, the second terminal device listens to the resources to determine a scheduling resource pool, and the scheduling resource pool includes one or more resource sets (or resources).

[0545] Among them, the granularity of the resource size can be a subchannel, or a resource block group (RBG), or a resource block (RB), etc.; there is no limitation on the granularity of the resource size.

[0546] Among them, for the process of "listening" to a resource or a set of resources, refer to Figure 9 the introduction in step 102 of

[0547] In another example, the second terminal device sends a resource set or a resource request to the network device, and the network device configures a resource set or a resource for the second terminal device; at this time, the second terminal device determines the resources for the first terminal device to perform data transmission in the resource set or the resource indicated by the network device. That is, the second terminal device obtains a scheduling resource pool from the network device, and the scheduling resource pool includes one or more resource sets (or resources).

[0548] In yet another example, the network device configures a resource or a resource set for the second terminal device; at this time, the second terminal device determines the resources for the first terminal device to perform data transmission in the resource or the resource set indicated by the network device. That is, the second terminal device determines a scheduling resource pool according to the configuration of the network device, and the scheduling resource pool includes one or more resource sets (or resources).

[0549] In still another example, the second terminal device has pre-configured resource sets or resources; at this time, the second terminal device determines the resources for the first terminal device to perform data transmission in the pre-configured resource sets or resources.

[0550] S302. Send scheduling information to the first terminal device, where the scheduling information is used to indicate the resources for the first terminal device to perform data transmission.

[0551] In one example, the scheduling information is specifically used to indicate the size and location anchor of the resources for performing data transmission.

[0552] In one example, the scheduling information is a physical layer sidelink control information, or a medium access control layer sidelink control information, or a radio resource control layer sidelink control information.

[0553] Exemplarily, after the second terminal device determines the resources for performing data transmission, it generates scheduling information. Among them, the scheduling information can be referred to as sidelink grant (SL grant) information.

[0554] In one example, the scheduling information indicates the resources for data transmission; to facilitate the first terminal device in determining the location of the resources, the scheduling information may indicate the size of the resources for data transmission and the location anchor of the resources for data transmission.

[0555] In one example, to facilitate the first terminal device in determining the resource set indicated by the scheduling information, the scheduling information may indicate the size and location anchor of the resource set, where the resource set is the resource set determined by the second terminal device. Since the scheduling information indicates the size and location anchor of the resource set, after receiving the scheduling information, the first terminal device can know how many resource sets or resources the second terminal device has allocated for the first terminal device.

[0556] In one example, the scheduling information indicates a resource set or a resource.

[0557] Then, the second terminal device selects resources from the scheduling resource pool and sends the scheduling information to the first terminal device.

[0558] In one example, the second terminal device sends the scheduling information to the first terminal device; where the scheduling information is a single signaling.

[0559] In another example, the scheduling information is physical layer sidelink control information; that is, the second terminal device sends the physical layer sidelink control information to the first terminal device, and the physical layer sidelink control information is used to indicate the resources for data transmission. For example, the physical layer sidelink control information may be 1 st stage SCI, or 2 nd stage SCI, or SCI.

[0560] In yet another example, the scheduling information is MAC layer sidelink control information; that is, the second terminal device sends the MAC layer sidelink control information to the first terminal device, and the MAC layer sidelink control information is used to indicate the resources for data transmission. For example, the MAC layer sidelink control information may be SL MAC CE information.

[0561] In still another example, the scheduling information is RRC layer sidelink control information; that is, the second terminal device sends the RRC layer sidelink control information to the first terminal device, and the RRC layer sidelink control information is used to indicate the resources for data transmission. For example, the RRC layer sidelink control information may be PC5 RRC information.

[0562] Furthermore, after the first terminal device receives the scheduling information, since the scheduling information directly indicates the resources available for the first terminal device, the first terminal device can use the resources indicated by the scheduling information for data transmission to send data. In one example, the scheduling information indicates a resource set or a resource, and thus the first terminal device uses the resource set or the resource to send data. In another example, the scheduling information indicates multiple resource sets or multiple resources, and thus the first terminal device uses the multiple resource sets or the multiple resources to send data.

[0563] For example, in Figure 7 the application scenario shown, both terminal device B and terminal device C have data to send to terminal device A. Terminal device C uses resource 1 to send data to terminal device A. Terminal device B sends a first message to terminal device A. Terminal device B is a hidden node of terminal device C, and terminal device B is unaware of the existence of terminal device C. However, terminal device A knows that terminal device C has used resource 1 to send data to terminal device A, and terminal device A can determine that resource 1 is already occupied. Consequently, the scheduling information generated by terminal device A will not indicate resource 1. Then, terminal device A returns the scheduling information to terminal device B. At this time, terminal device B determines based on the scheduling information that resource 1 is already occupied and will no longer use resource 1. Terminal device B can use the resources indicated by the scheduling information to send data to terminal device A. This can avoid terminal device C and terminal device B using the same resource to send data, prevent signal collisions and mutual interference during data transmission, and ensure the successful data transmission of both terminal device C and terminal device B.

[0564] For another example, in Figure 8 the application scenario shown, in the case of resource reuse, terminal device B has data to send to terminal device A, and terminal device C has data to send to terminal device D. Terminal device C uses resource 1 to send data to terminal device D. Terminal device B sends a first message to terminal device A. Terminal device A can determine that resource 1 is not occupied, and thus the scheduling information generated by terminal device A can indicate resource 1. Then, terminal device A returns the scheduling information to terminal device B. At this time, terminal device B determines based on the scheduling information that resource 1 is not occupied, and terminal device B can use resource 1 to send data to terminal device A. Furthermore, in the case of resource reuse, terminal device B can use resource 1 to send data to terminal device A, and terminal device A will not be interfered by the signal sent by terminal device C on resource 1. Through the solution provided in this embodiment, resources are reasonably utilized, and the resource utilization efficiency is improved.

[0565] Figure 23This is a signaling diagram of another device - to - device resource determination method provided by an embodiment of the present application, which is used to implement Figure 22 each step. As Figure 23 shown, the method includes:

[0566] S231. The second terminal device determines the resources for data transmission.

[0567] S232. The second terminal device sends scheduling information to the first terminal device, where the scheduling information is used to indicate the resources for the first terminal device to transmit data.

[0568] S233. The first terminal device sends data according to the resources for data transmission.

[0569] Here, for S231, reference can be made to step S301 of Figure 22 ; for S232, reference can be made to step S302 of Figure 22 ; for S233, reference can be made to step S302 of Figure 22 . Details will not be repeated.

[0570] In this embodiment, the second terminal device determines the resources for data transmission; the second terminal device sends scheduling information to the first terminal device, and the scheduling information is used to indicate the resources for the first terminal device to transmit data. When the first terminal device needs to send data, the second terminal device determines the resources for data transmission, the second terminal device generates scheduling information, and the scheduling information indicates the resources for the first terminal device to transmit data; then the second terminal device schedules resources for the first terminal device; the first terminal device can send data according to the resources indicated by the scheduling information. Through the above process, when the first terminal device needs to send data, the second terminal device schedules resources for the first terminal device, that is, other terminal devices (the terminal device that receives data, or a terminal device that is not the data - receiving terminal device) schedule resources for the first terminal device to transmit data, rather than the terminal device that sends data completely determining the resources for data transmission by itself; the resources indicated by the second terminal device can directly exclude the resources occupied by other hidden terminals, which can avoid different terminal devices using the same resource to send data, avoid signal collisions and mutual interference during the data transmission process, and ensure the successful data transmission of different terminal devices; and for the case of resource reuse, resources can be reasonably utilized, improving resource utilization efficiency.

[0571] Figure 24 This is a signaling diagram of another device - to - device resource determination method provided by an embodiment of the present application. As Figure 24 shown, the method includes:

[0572] S241. The second terminal device determines the channel state information.

[0573] In one example, step S241 includes the following implementation manners:

[0574] The first implementation manner of step S241:

[0575] The first step: The second terminal device sends first channel state information reference signal configuration information to the first terminal device, where the first channel state information reference signal configuration information is used to indicate receiving a channel state information reference signal.

[0576] The second step: The second terminal device sends a channel state information reference signal to the first terminal device, and the channel state information reference signal is used to determine channel state information.

[0577] The third step: The second terminal device receives the channel state information sent by the first terminal device.

[0578] The second implementation manner of step S241:

[0579] The first step: The second terminal device sends second channel state information reference signal configuration information to the first terminal device, where the second channel state information reference signal configuration information is used to indicate sending a channel state information reference signal.

[0580] The second step: The second terminal device receives the channel state information reference signal sent by the first terminal device, where the channel state information reference signal is used to determine channel state information.

[0581] The third step: The second terminal device determines channel state information according to the channel state information reference signal.

[0582] Exemplarily, the first terminal device is a data sending end, the second terminal device is a data receiving end, and the second terminal device is a scheduling end. That is, the second terminal device has the ability to schedule resources for data transmission. In this embodiment, the second terminal device schedules resources for the first terminal device.

[0583] The second terminal device needs to determine the channel state information for communicating with the first terminal device.

[0584] In one example, a second terminal device sends first CSI-RS configuration information to a first terminal device, where the first CSI-RS configuration information is used to instruct the first terminal device to receive CSI-RS; in one example, the CSI-RS configuration information is PC5 RRC information. The second terminal device sends CSI-RS to the first terminal device, and the CSI-RS is used to determine channel state information. Then, after receiving the CSI-RS, the first terminal device performs channel measurement according to the CSI-RS to obtain a measurement result; the first terminal device obtains channel state information according to the measurement result. The first terminal device sends the channel state information to the second terminal device, and then the second terminal device obtains the channel state information.

[0585] In another example, a second terminal device sends second CSI-RS configuration information to a first terminal device, where the second CSI-RS configuration information is used to instruct the first terminal device to send CSI-RS; in one example, the CSI-RS configuration information is PC5 RRC information. The first terminal device sends CSI-RS to the second terminal device, and the CSI-RS is used to determine channel state information. Then, after receiving the CSI-RS, the second terminal device performs channel measurement according to the CSI-RS to obtain a measurement result; the second terminal device obtains channel state information according to the measurement result.

[0586] Step S241 is an optional step.

[0587] S242. The first terminal device sends first information to the second terminal device, where the first information is used to indicate a resource for requesting data transmission.

[0588] In one example, a preset indication field or a preset bit in the first information is used to indicate a resource for requesting data transmission.

[0589] In one example, the first information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0590] Exemplarily, before the first terminal device needs to send data to the second terminal device, it first sends first information to the second terminal device, where the first information is used to indicate a resource for requesting data transmission. In this embodiment, the first information may also be referred to as a "scheduling request (SR)".

[0591] In one example, the first terminal device listens for a resource and then uses the listened resource to send the first information to the second terminal device.

[0592] Alternatively, the second terminal device sends configuration information of the first information to the first terminal device, where the configuration information of the first information is used to indicate the resource for transmitting the first information; thus, the first terminal device sends the first information to the second terminal device according to the resource indicated by the configuration information of the first information. For example, the second terminal device sends configuration information of the SR to the first terminal device, where the configuration information of the SR is used to indicate the resource for transmitting the SR; thus, the first terminal device sends the SR to the second terminal device according to the resource indicated by the configuration information of the SR.

[0593] In one example, the first terminal device sends the first information to the second terminal device. The first information is a single signaling, and there are multiple indication fields in the first information. One preset indication field among the multiple indication fields can be used to indicate the resource for requesting data transmission; the position of the preset indication field in the first information and the size of the preset indication field are not limited. Alternatively, the first information is a single signaling, and there are multiple bits in the first information. One preset bit among the multiple indication fields can be used to indicate the resource for requesting data transmission; the position of the preset bit in the first information and the size of the preset bit are not limited.

[0594] In another example, the first information is the physical layer sidelink control information; the preset indication field in the physical layer sidelink control information is used to indicate the resource for requesting data transmission, or the preset bit in the physical layer sidelink control information is used to indicate the resource for requesting data transmission. The physical layer sidelink control information can indicate the resource for requesting data transmission in an explicit manner, or the physical layer sidelink control information can indicate the resource for requesting data transmission in an implicit manner. For example, the physical layer sidelink control information can be 1 st stageSCI, or 2 nd stage SCI, or SCI.

[0595] For example, the first information is 2 nd stage SCI, 2 nd There is a preset indication field in stage SCI; when the value in the preset indication field is the first value, it represents the resource for requesting data transmission; when the value in the preset indication field is the second value, it represents that there is no need to request data transmission; and, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, that is, 2 nd stage SCI includes the identifier of the terminal device that sends 2 nd stage SCI, and the identifier of the terminal device that receives 2 ndThe identifier of the terminal device of stage SCI. At this time, the first information requests resources for data transmission in an explicit manner. For example, the first terminal device sends 2 to the second terminal device nd stage SCI, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; 2 nd There is a 1-bit indication field in stage SCI, and the 1-bit indication field is used to indicate whether to request resources for data transmission; when the value in the 1-bit indication field is 1, it means to request resources for data transmission, and when the value in the 1-bit indication field is 0, it means not to request resources for data transmission.

[0596] For example, the first information is 1 st stage SCI, 1 st There is a preset indication field in stage SCI; when the value in the preset indication field is the first value, it represents requesting resources for data transmission; when the value in the preset indication field is the second value, it represents not requesting resources for data transmission. And, the second terminal device receives 1 st before receiving 1 st stage SCI or after receiving 1 nd stage SCI, and also receives the identification information sent by the first terminal device, and the identification information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identification information is 2 st stage SCI and 2 nd stage SCI; 1 st There is a 1-bit indication field in stage SCI, and the 1-bit indication field is used for whether to request resources for data transmission; when the value in the 1-bit indication field is 1, it means to request resources for data transmission, and when the value in the 1-bit indication field is 0, it means not to request resources for data transmission; 2 nd stage SCI is used to indicate the identifier of the first terminal device and the identifier of the second terminal device.

[0597] For example, the first information is 2 nd stage SCI; 2 ndThere are preset bit positions in the stage SCI; when the preset bit position is the first bit sequence, it represents the resource for requesting data transmission, and the first bit sequence includes at least one bit position; when the preset bit position is the second bit sequence, it represents the resource that does not need to request data transmission, and the second bit sequence includes at least one bit position; the first bit sequence and the second bit sequence are different bit sequences. And, 2 nd The stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, 2 nd The stage SCI includes sending 2 nd the identifier of the terminal device of the stage SCI, and receiving 2 nd the identifier of the terminal device of the stage SCI. At this time, the first information requests the resource for data transmission in an implicit manner. For example, the first terminal device sends 2 nd the stage SCI, 2 nd The stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; 2 nd There is a CRC in the stage SCI. At this time, 1-bit scrambling is performed on 2 nd the last bit position of the CRC of the stage SCI; scrambling with 1 indicates the resource for requesting data transmission, and scrambling with 0 indicates the resource that does not need to request data transmission. For example, 2 nd The CRC of the stage SCI is the 24-bit bit sequence 0101 1010 0101 1010 0101 1010, and the CRC scrambled with 1 is 0101 1010 0101 1010 0101 1011. At this time, it indicates the resource for requesting data transmission.

[0598] For example, the first information is 1 st the stage SCI, 1 st There are preset bit positions in the stage SCI; when the preset bit position is the first bit sequence, it represents the resource for requesting data transmission, and the first bit sequence includes at least one bit position; when the preset bit position is the second bit sequence, it represents the resource that does not need to request data transmission, and the second bit sequence includes at least one bit position; the first bit sequence and the second bit sequence are different bit sequences. And, the second terminal device receives 1 st before receiving the stage SCI or after receiving 1 st the stage SCI, and also receives the identification information sent by the first terminal device. The identification information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identification information is 2 ndstage SCI; thus, the second terminal device can know that it is the first terminal device that requests resources for data transmission. At this time, the first information indicates the resources for requesting data transmission in an implicit manner. For example, the first terminal device sends 1 to the second terminal device st stage SCI and 2 nd stage SCI; 1 st There is a CRC in the stage SCI. At this time, 1 bit is scrambled on the last bit of the CRC of the 1 st stage SCI; scrambling with 1 indicates the resources for requesting data transmission, and scrambling with 0 indicates that there is no need to request resources for data transmission; 2 nd The stage SCI is used to indicate the identifier of the first terminal device and the identifier of the second terminal device. For example, 1 st The CRC of the stage SCI is the 24-bit bit sequence 01011010 0101 1010 0101 1010. The CRC scrambled with 1 is 0101 1010 0101 1010 0101 1011. At this time, it indicates the resources for requesting data transmission.

[0599] In another example, the first information is MAC layer sidelink control information; the preset indication field in the MAC layer sidelink control information is used to indicate the resources for requesting data transmission, or the preset bit in the MAC layer sidelink control information is used to indicate the resources for requesting data transmission. Among them, the MAC layer sidelink control information can indicate the resources for requesting data transmission in an explicit manner, or the MAC layer sidelink control information can indicate the resources for requesting data transmission in an implicit manner. For example, the MAC layer sidelink control information can be SL MAC CE information.

[0600] For example, the first information is SL MAC CE information, and there is a preset indication field in the SL MAC CE information; when the value in the preset indication field is the first value, it represents the resources for requesting data transmission; when the value in the preset indication field is the second value, it represents that there is no need to request resources for data transmission, and the first value and the second value are different. Moreover, before or after receiving the SL MAC CE information, the second terminal device also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identification information is 2 ndstage SCI; thus, the second terminal device can learn that it is the first terminal device that requests resources for data transmission. At this time, the first information indicates the resources for which data transmission is requested in an explicit manner. For example, the first terminal device sends SL MAC CE information and 2 nd stage SCI to the second terminal device; there is a preset indication field in the SL MAC CE information, and the preset indication field is used to indicate whether to request resources for data transmission; when the value in the preset indication field is 1, it means that resources for data transmission are requested, and when the value in the preset indication field is 0, it means that resources for data transmission are not required; 2 nd stage SCI is used to indicate the identifier of the first terminal device and the identifier of the second terminal device.

[0601] In another example, the first information is RRC layer sidelink control information; the preset indication field in the RRC layer sidelink control information is used to indicate the resources for which data transmission is requested, or the preset bit in the RRC layer sidelink control information is used to indicate the resources for which data transmission is requested. Among them, the RRC layer sidelink control information can indicate the resources for which data transmission is requested in an explicit manner, or the RRC layer sidelink control information can indicate the resources for which data transmission is requested in an implicit manner. For example, the RRC layer sidelink control information can be PC5 RRC information.

[0602] For example, the first information is PC5 RRC information, and there is a preset indication field in the PC5 RRC information; when the value in the preset indication field is the first value, it represents that resources for data transmission are requested; when the value in the preset indication field is the second value, it represents that resources for data transmission are not required, and the first value and the second value are different. Also, before or after receiving the PC5 RRC information, the second terminal device also needs to receive the identification information sent by the first terminal device, and the identification information is used to indicate the identifier of the first terminal device and the identifier of the second terminal device; for example, the identification information is 2 nd stage SCI; thus, the second terminal device can learn that it is the first terminal device that requests resources for data transmission. At this time, the first information indicates the resources for which data transmission is requested in an explicit manner. For example, the first terminal device sends PC5 RRC information and 2 nd stage SCI to the second terminal device; there is a preset indication field in the PC5 RRC information, and the preset indication field is used to indicate whether to request resources for data transmission; the preset indication field can be indicated by an integer. When the value in the preset indication field is 1, it means that resources for data transmission are requested, and when the value in the preset indication field is 0, it means that resources for data transmission are not required; 2 ndThe stage SCI is used to indicate the identifier of the first terminal device and the identifier of the second terminal device. For another example, the first terminal device sends PC5 RRC information and 2 nd the stage SCI to the second terminal device; there is a preset indication field in the PC5 RRC information, and the preset indication field is used to indicate whether to request resources for data transmission; the preset indication field can be indicated by an enumeration type, and the members of the enumeration type include activate and deactivate. When the preset indication field is activate, it means to request resources for data transmission, and when the preset indication field is deactivate, it means not to request resources for data transmission; 2 nd The stage SCI is used to indicate the identifier of the first terminal device and the identifier of the second terminal device.

[0603] S243. The first terminal device sends a buffer status report message to the second terminal device, where the buffer status report message is used to indicate the size of the data to be transmitted.

[0604] In one example, the preset indication field or the scrambled bit in the buffer status report message is used to indicate the size of the data to be transmitted.

[0605] In one example, the buffer status report message is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information.

[0606] Exemplarily, the first terminal device sends a BSR message to the second terminal device. In order to facilitate the second terminal device to determine appropriate resources for the first terminal device, the BSR message needs to indicate the size of the data to be transmitted by the first terminal device. For example, the BSR message includes an index of the size of the data to be transmitted in the buffer, or the BSR message includes the size of the data to be transmitted in the buffer; that is, the "size of the data to be transmitted" refers to the index of the size of the data to be transmitted in the buffer, or refers to the size of the data to be transmitted in the buffer. In one example, the first terminal device determines the resources in a listening manner, and the resources are used to transmit the BSR message; then, the first terminal device uses the listened resources to send the BSR message to the second terminal device.

[0607] For the BSR message, reference can be made to Figure 12 the introduction in step S24 shown, which will not be elaborated here.

[0608] In one example, a first terminal device sends BSR information to a second terminal device. The BSR information is a separate signaling, and there are multiple indication fields in the BSR information. One preset indication field among the multiple indication fields can be used to indicate the size of the data to be transmitted; the position of the preset indication field in the BSR information and the size of the preset indication field are not restricted. Alternatively, the BSR information is a separate signaling, and there are multiple bits in the BSR information. One preset bit among the multiple indication fields can be used to indicate the size of the data to be transmitted; the position of the preset bit in the BSR information and the size of the preset bit are not restricted.

[0609] In another example, the BSR information is physical layer sidelink control information; the preset indication field in the physical layer sidelink control information is used to indicate the size of the data to be transmitted, or the preset bit in the physical layer sidelink control information is used to indicate the size of the data to be transmitted. The physical layer sidelink control information can indicate the size of the data to be transmitted in an explicit manner, or the physical layer sidelink control information can indicate the size of the data to be transmitted in an implicit manner. For example, the physical layer sidelink control information can be 1 st stage SCI, or 2 nd stage SCI, or SCI.

[0610] In yet another example, the BSR information is MAC layer sidelink control information; the preset indication field in the MAC layer sidelink control information is used to indicate the size of the data to be transmitted, or the preset bit in the MAC layer sidelink control information is used to indicate the size of the data to be transmitted. The MAC layer sidelink control information can indicate the size of the data to be transmitted in an explicit manner, or the MAC layer sidelink control information can indicate the size of the data to be transmitted in an implicit manner. For example, the MAC layer sidelink control information can be SL MACCE information.

[0611] In still another example, the BSR information is RRC layer sidelink control information; the preset indication field in the RRC layer sidelink control information is used to indicate the size of the data to be transmitted, or the preset bit in the RRC layer sidelink control information is used to indicate the size of the data to be transmitted. The RRC layer sidelink control information can indicate the size of the data to be transmitted in an explicit manner, or the RRC layer sidelink control information can indicate the size of the data to be transmitted in an implicit manner. For example, the RRC layer sidelink control information can be PC5 RRC information.

[0612] Among them, there is no requirement for the execution order among the three steps S241, S242, and S243.

[0613] S244. The second terminal device determines the resources for data transmission.

[0614] In one example, step S243 specifically includes: determining the resources for data transmission according to the buffer status report message.

[0615] Exemplarily, after receiving the first information and the BSR information, the second terminal device determines the resources requested by the first terminal device for data transmission according to the first information; thus, the second terminal device needs to return scheduling information to the first terminal device; however, before returning the scheduling information, it is necessary to first determine the resources for data transmission.

[0616] In one example, the second terminal device determines the resource size according to the obtained channel state information; the second terminal device listens with the resource size as the granularity to obtain a scheduling resource pool, and the scheduling resource pool includes one or more resource sets (or resources). Then, the second terminal device selects, from the scheduling resource pool, the resource set (or resource) that can carry the data to be transmitted according to the size of the data to be transmitted indicated by the BSR information, and at this time, the "resources for data transmission" are determined.

[0617] In another example, the second terminal device sends a resource set or a resource request to the network device, and the network device configures a resource set or a resource for the second terminal device; further, the second terminal device determines a scheduling resource pool, and the scheduling resource pool includes one or more resource sets (or resources). Then, the second terminal device selects, from the scheduling resource pool, the resource set (or resource) that can carry the data to be transmitted according to the size of the data to be transmitted indicated by the BSR information, and at this time, the "resources for data transmission" are determined.

[0618] In yet another example, the network device configures a scheduling resource pool for the second terminal device, and the scheduling resource pool includes one or more resource sets (or resources). Then, the second terminal device selects, from the scheduling resource pool, the resource set (or resource) that can carry the data to be transmitted according to the size of the data to be transmitted indicated by the BSR information, and at this time, the "resources for data transmission" are determined.

[0619] In still another example, the second terminal device is pre-configured with a scheduling resource pool, and the scheduling resource pool includes one or more resource sets (or resources). Then, the second terminal device selects, from the scheduling resource pool, the resource set (or resource) that can carry the data to be transmitted according to the size of the data to be transmitted indicated by the BSR information, and at this time, the "resources for data transmission" are determined.

[0620] Among them, the granularity of the resource size can be a sub-channel, or a resource block group, or a resource block, etc.; there is no limitation on the granularity of the resource size.

[0621] S245. The second terminal device sends scheduling information to the first terminal device, where the scheduling information is used to indicate the resources for the first terminal device to perform data transmission.

[0622] In one example, the scheduling information is specifically used to indicate the size and location anchor of the resources for data transmission.

[0623] In one example, the scheduling information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

[0624] Exemplarily, after determining the "resources for data transmission", the second terminal device generates scheduling information. The second terminal device sends the scheduling information to the first terminal device.

[0625] Regarding the number of resource sets (resources) indicated by the "scheduling information", there can be the following several implementation manners.

[0626] For the number of resource sets (resources) indicated by the "scheduling information", the first implementation manner: In one example, the scheduling information indicates one resource set (or one resource); at this time, in order to facilitate the first terminal device to determine the position of the resource set (resource), the scheduling information can also indicate the size of the resource set (or resource), and the location anchor of the resource set (or resource).

[0627] For the number of resource sets (resources) indicated by the "scheduling information", the second implementation manner: The scheduling information indicates multiple resource sets (or multiple resources). At this time, the sizes of different resource sets (resources) can be the same or different, but the location anchors of different resource sets (resources) are different. The location anchor refers to the start point, or end point, or midpoint, etc. of the resource set (resource).

[0628] Next, regarding "the scheduling information indicates multiple resource sets (or multiple resources)", it will be introduced taking "resources" as an example.

[0629] In one example, the scheduling information includes the first indication information of each resource, and the first indication information is used to indicate the size and location anchor of the resource; at this time, the scheduling information can indicate multiple unoccupied resources, and each resource has its own first indication information, that is, the first indication information is an indication of an unoccupied resource, and the first indication information can be represented by an index value; the first indication information of each resource indicates the size and location anchor of the resource.

[0630] In another example, the scheduling information includes second indication information for each resource and third indication information for each resource. The second indication information is used to indicate the size of the resource, and the third indication information is used to indicate the position anchor of the resource. At this time, the scheduling information can indicate multiple unoccupied resources, and each resource has its own second indication information and third indication information. For example, the scheduling information includes an indication for each resource, and this indication can be represented by a field; this field includes sub-field 1 and sub-field 2, where sub-field 1 indicates the size of the resource and sub-field 2 indicates the position anchor of the resource.

[0631] In yet another example, the scheduling information includes fourth indication information and fifth indication information for each resource; the fourth indication information is used to indicate the size of the resource, and the size of each resource is the same; the fifth indication information is used to indicate the position anchor of the resource. At this time, the scheduling information can indicate multiple unoccupied resources. Since the sizes of the resources are the same, the same fourth indication information can be used to indicate the size of the resources. For example, a single field is used to uniformly indicate the size of the resources; each resource has its own fifth indication information, and the fifth indication information is used to indicate the position anchor of the resource, that is, the position anchors of the resources are indicated by different fields respectively.

[0632] In addition, the number of resources indicated by the scheduling information is the number of all unoccupied resources; or, the number of resources indicated by the scheduling information is a preset number.

[0633] In one example, there is no limit to the number of resources indicated by the scheduling information. That is, when the second terminal device determines all unoccupied resources, the second terminal device can use the scheduling information to indicate all unoccupied resources. It can be seen that the scheduling information sent by the second terminal device to the first terminal device can indicate as many unoccupied resources as possible.

[0634] In another example, the number of resources indicated by the scheduling information is restricted. That is, the scheduling information sent by the second terminal device to the first terminal device can indicate N unoccupied resources, where N is a positive integer greater than or equal to 1. If the number of unoccupied resources determined by the second terminal device is N, then the number of resources indicated by the scheduling information is N. If the number of unoccupied resources determined by the second terminal device is greater than N, N resources are selected from them, for example, the N resources with the minimum noise and interference power on the resources; the number of resources indicated by the scheduling information is N. If the number of unoccupied resources determined by the second terminal device is less than N, for example, it is M, where M is a positive integer greater than or equal to 1 and less than N; then the scheduling information indicates these M resources; or, the scheduling information indicates these M resources, and the remaining fields used to indicate resources in the scheduling information are set to empty (or set to zero).

[0635] For example, limit the number of resources indicated by the scheduling information to 3. If the number of unoccupied resources determined by the second terminal device is 3, then the number of resources indicated by the scheduling information is 3. If the number of unoccupied resources determined by the second terminal device is greater than 3, select 3 resources therefrom, for example, select the 3 resources with the minimum noise and interference power on the resources; the number of resources indicated by the scheduling information is 3. If the number of unoccupied resources determined by the second terminal device is less than 3, for example, 2, then the scheduling information indicates these 2 resources, or the scheduling information indicates these 2 resources and the third available resource field is set to empty (or zero).

[0636] When limiting the number of resources indicated by the scheduling information, the number of resources can be specified. For example, the maximum value of the number of resources indicated by the scheduling information is 3.

[0637] Alternatively, when limiting the number of resources indicated by the scheduling information, the first terminal device sends a second message to the second terminal device, where the second message is for the maximum number of resources; thus, the first terminal device limits the maximum number of resources returned by the second terminal device. In one example, the second message is a physical layer sidelink control information, or a MAC layer sidelink control information, or an RRC layer sidelink control information.

[0638] In one example, the first terminal device sends a second message to the second terminal device; where the second message is a separate signaling.

[0639] In another example, the second message is a physical layer sidelink control information; that is, the first terminal device sends a physical layer sidelink control information to the second terminal device, and the physical layer sidelink control information is for the maximum number of resources. For example, the physical layer sidelink control information can be 1 st stage SCI, or 2 nd stage SCI, or SCI.

[0640] In yet another example, the second message is a MAC layer sidelink control information; that is, the first terminal device sends a MAC layer sidelink control information to the second terminal device, and the MAC layer sidelink control information is for the maximum number of resources. For example, the MAC layer sidelink control information can be an SL MAC CE information.

[0641] In still another example, the second message is an RRC layer sidelink control information; that is, the first terminal device sends an RRC layer sidelink control information to the second terminal device, and the RRC layer sidelink control information is for the maximum number of resources. For example, the RRC layer sidelink control information can be a PC5 RRC information.

[0642] Then, the second terminal device uses the resources in the scheduling resource pool to send scheduling information to the first terminal device.

[0643] In one example, the second terminal device sends scheduling information to the first terminal device; wherein, the scheduling information is a separate signaling.

[0644] In another example, the scheduling information is physical layer sidelink control information; that is, the second terminal device sends physical layer sidelink control information to the first terminal device, and the physical layer sidelink control information is used to indicate the resources for data transmission. For example, the physical layer sidelink control information may be 1 st stage SCI, or 2 nd stage SCI, or SCI.

[0645] In yet another example, the scheduling information is MAC layer sidelink control information; that is, the second terminal device sends MAC layer sidelink control information to the first terminal device, and the MAC layer sidelink control information is used to indicate the resources for data transmission. For example, the MAC layer sidelink control information may be SL MAC CE information.

[0646] In still another example, the scheduling information is RRC layer sidelink control information; that is, the second terminal device sends RRC layer sidelink control information to the first terminal device, and the RRC layer sidelink control information is used to indicate the resources for data transmission. For example, the RRC layer sidelink control information may be PC5 RRC information.

[0647] S246. The first terminal device sends sidelink control information to the second terminal device.

[0648] Exemplarily, the first terminal device sends sidelink control information to the second terminal device, and the sidelink control information is used to indicate information such as MCS for data transmission. That is, before the first terminal device sends data to the second terminal device, the first terminal device needs to indicate the necessary information such as MCS for data reception; then, the first terminal device uses the sidelink control information to inform the second terminal device of the necessary information for data reception.

[0649] In one example, the first terminal device uses the resources indicated by the scheduling information in step S245 to send sidelink control information to the second terminal device.

[0650] In one example, the sidelink control information is physical layer sidelink control information, or MAC layer sidelink control information, or RRC layer sidelink control information. For example, the sidelink control information is 1st stage SCI, or 2nd stage SCI, or SCI.

[0651] Step S246 is an optional step. If step S246 is not executed, it may be stipulated in the protocol that both the first terminal device and the second terminal device have learned the above necessary information for data reception.

[0652] Among them, the execution order between step S246 and the above steps S241 - S245 is not limited, as long as step S246 is executed before step S247.

[0653] S247. The first terminal device sends data to the second terminal device according to the resources for data transmission.

[0654] Exemplarily, if the scheduling information indicates a resource set (or a resource), the second terminal device sends data to the second terminal device according to the resource set (or the resource). If the scheduling information indicates multiple resource sets (or resources), the second terminal device sends data to the second terminal device according to the multiple resource sets (or resources).

[0655] It can be seen that the first terminal device does not need to listen for resources by itself, but only needs to select resources according to the indication of the scheduling information.

[0656] In this embodiment, the first terminal device is the data sender, and the second terminal device is the data receiver; moreover, the second terminal device has the ability to schedule the resources for data transmission, that is, the second terminal device is also the scheduling side. The second terminal device schedules resources for the first terminal device. The first terminal device sends the first information to the second terminal device, and the first information is used to indicate the resources requested for data transmission; the second terminal device can determine that the first terminal device needs to obtain resources to send data, the second terminal device determines the resources for data transmission, and then sends scheduling information to the first terminal device, and the scheduling information indicates the resources for the first terminal device to transmit data; and then the first terminal device sends data according to the resources indicated by the scheduling information. Through the above process, when the first terminal device needs to send data, the second terminal device schedules resources for the first terminal device, rather than the terminal device sending data completely determining the resources for data transmission by itself; the resources indicated by the second terminal device can directly exclude the resources occupied by other hidden terminals, which can avoid different terminal devices using the same resource to send data, avoid signal collisions and mutual interference during the data transmission process, and make the data transmission of different terminal devices all successful; and for the case of resource reuse, it can make the resources be reasonably utilized and improve the resource utilization efficiency. Moreover, the first terminal device can also send BSR information to the second terminal device, so that when the second terminal device determines the scheduling information, it can more reasonably calculate the resource granularity for listening according to the size of the data to be transmitted indicated by the BSR information, and then determine the resources suitable for the first terminal device to transmit data, making the resources be reasonably utilized.

[0657] Figure 25 This is a signaling diagram of another device - to - device based resource determination method provided by an embodiment of this application. As Figure 25 shown, this method includes:

[0658] S251. The second terminal device determines the channel state information.

[0659] Exemplarily, the first terminal device is the data sender, the second terminal device is the data scheduler, and the third terminal device is the data receiver. That is, the second terminal device has the ability to schedule resources. In this embodiment, the second terminal device schedules resources for the first terminal device.

[0660] The second terminal device needs to determine the channel state information for communicating with the first terminal device.

[0661] This step can refer to Figure 24 step S241 of, which will not be elaborated here. Step S251 is an optional step.

[0662] S252. The first terminal device sends a first message to the second terminal device, where the first message is used to indicate the resources requested for data transmission.

[0663] In one example, a preset indication field or preset bit in the first message is used to indicate the resources requested for data transmission.

[0664] In one example, the first message is a physical layer sidelink control information, or a MAC layer sidelink control information, or an RRC layer sidelink control information.

[0665] Exemplarily, before the first terminal device needs to send data to the second terminal device, it first sends a first message to the second terminal device, and the first message is used to indicate the resources requested for data transmission. In this embodiment, the first message can also be referred to as a "scheduling request".

[0666] In one example, the first terminal device listens for resources and then uses the listened - for resources to send the first message to the second terminal device.

[0667] Alternatively, the second terminal device sends configuration information of the first message to the first terminal device, where the configuration information of the first message is used to indicate the resources for transmitting the first message; thus, the first terminal device sends the first message to the second terminal device according to the resources indicated by the configuration information of the first message. For example, the second terminal device sends the configuration information of SR to the first terminal device, where the configuration information of SR is used to indicate the resources for transmitting SR; thus, the first terminal device sends SR to the second terminal device according to the resources indicated by the configuration information of SR.

[0668] In one example, the first terminal device indicates its identity to the second terminal device. The first terminal device is the receiver of scheduling information. Thus, when the second terminal device schedules and allocates resources for data transmission, it needs to know who the receiver of the scheduling information is, that is, it needs to know who the receiver of the data transmission resources is. At this time, the second terminal device can know that the receiver of the scheduling information is the first terminal device, rather than itself. For example, the first piece of information carries the identity of the first terminal device. For another example, the first terminal device sends the third piece of information to the second terminal device, and the third piece of information is used to indicate the identity of the first terminal device. The third piece of information is a physical layer sidelink control information, or a MAC layer sidelink control information, or an RRC layer sidelink control information. At this time, the action of "the first terminal device sends the third piece of information to the second terminal device" only needs to be executed before step S254.

[0669] Alternatively, the first terminal device does not need to indicate its identity to the second terminal device. The first terminal device is the receiver of scheduling information. Thus, when the second terminal device schedules and allocates resources for data transmission, it does not need to know who the receiver of the scheduling information is, that is, it does not need to know who the receiver of the data transmission resources is. At this time, the second terminal device can directly send the scheduling information to the first terminal device. For example, the first piece of information does not need to carry the identity of the first terminal device. For another example, the first terminal device does not need to send the third piece of information to the second terminal device.

[0670] In one example, the first terminal device indicates to the second terminal device who the user of the data transmission resources is. The first piece of information is also used to indicate the user of the data transmission resources. Or, the first terminal device sends the fourth piece of information to the second terminal device, and the fourth piece of information is used to indicate the user of the data transmission resources. If the user of the data transmission resources is the first terminal device, then when the second terminal device allocates the data transmission resources, it knows that the allocated data transmission resources are for the first terminal device to use for data transmission. At this time, the second terminal device knows that it does not use the resources indicated by the scheduling information. If the user of the data transmission resources is the second terminal device, then when the second terminal device allocates the data transmission resources, it knows that the allocated data transmission resources are for the second terminal device to use for data transmission. At this time, the second terminal device knows that it can use the resources indicated by the scheduling information. Among them, the fourth piece of information is a physical layer sidelink control information, or a MAC layer sidelink control information, or an RRC layer sidelink control information. At this time, the action of "the first terminal device sends the fourth piece of information to the second terminal device" only needs to be executed before step S254.

[0671] In one example, the first terminal device indicates to the second terminal device who the recipient of the data is. The first information is also used to indicate the recipient of the data; alternatively, the first terminal device sends the fifth information to the second terminal device, and the fifth information is used to indicate the recipient of the data. In this embodiment, the recipient of the data is the third terminal device. Wherein, the fifth information is a physical layer sidelink control information, or a MAC layer sidelink control information, or an RRC layer sidelink control information. At this time, the action of "the first terminal device sends the fifth information to the second terminal device" only needs to be executed before step S254.

[0672] In one example, the first terminal device sends the first information to the second terminal device. Wherein, the first information is a separate signaling, and the first information has multiple indication fields. One of the multiple indication fields, a preset indication field, can be used to indicate the resource for requesting data transmission; the position of the preset indication field in the first information and the size of the preset indication field are not limited. Alternatively, the first information is a separate signaling, and the first information has multiple bits. One of the multiple indication fields, a preset bit, can be used to indicate the resource for requesting data transmission; the position of the preset bit in the first information and the size of the preset bit are not limited.

[0673] Wherein, the first information carries the identifier of the first terminal device, or the first terminal device sends the third information to the second terminal device, and the third information is used to indicate the identifier of the first terminal device; thus, the second terminal device can know that the recipient of the scheduling information is the first terminal device. Or, the first information does not need to carry the identifier of the first terminal device, and the first terminal device does not need to send the third information to the second terminal device; thus, the second terminal device does not need to know who the recipient of the scheduling information is and can directly send the scheduling information to the first terminal device.

[0674] The first information is also used to indicate that the user of the resource for data transmission is the first terminal device; or, the first terminal device sends the fourth information to the second terminal device, and the fourth information is used to indicate that the user of the resource for data transmission is the first terminal device. Thus, the second terminal device knows that the resource for data transmission needs to be allocated to the first terminal device for data transmission.

[0675] The first information is also used to indicate that the recipient of the data is the third terminal device; or, the first terminal device sends the fifth information to the second terminal device, and the fifth information is used to indicate that the recipient of the data is the third terminal device.

[0676] In another example, the first information is the physical layer sidelink control information; a preset indication field or a preset bit in the physical layer sidelink control information is used to indicate the resources for which data transmission is requested. Among them, the physical layer sidelink control information can indicate the resources for which data transmission is requested in an explicit or implicit manner. For example, the physical layer sidelink control information can be 1 st stage SCI, or 2 nd stage SCI, or SCI.

[0677] The physical layer sidelink control information carries the identifier of the first terminal device, or the first terminal device sends third information to the second terminal device, and the third information is used to indicate the identifier of the first terminal device; thus, the second terminal device can know that the receiving end of the scheduling information is the first terminal device. Or, the physical layer sidelink control information does not need to carry the identifier of the first terminal device, and the first terminal device does not need to send third information to the second terminal device; thus, the second terminal device does not need to know who the receiving end of the scheduling information is, and can directly send the scheduling information to the first terminal device.

[0678] The physical layer sidelink control information is also used to indicate that the user of the resources for data transmission is the first terminal device; or, the first terminal device sends fourth information to the second terminal device, and the fourth information is used to indicate that the user of the resources for data transmission is the first terminal device. Thus, the second terminal device knows that the resources for data transmission need to be allocated to the first terminal device for data transmission.

[0679] The physical layer sidelink control information is also used to indicate that the receiving end of the data is the third terminal device; or, the first terminal device sends fifth information to the second terminal device, and the fifth information is used to indicate that the receiving end of the data is the third terminal device.

[0680] For example (referred to as "Example 1"), the first information is 2 nd stage SCI, 2 nd There is a preset indication field in stage SCI; when the value in the preset indication field is the first value, it represents the resources for which data transmission is requested; when the value in the preset indication field is the second value, it represents that data transmission is not requested. At this time, the first information requests the resources for data transmission in an explicit manner. For example, the first terminal device sends 2 nd stage SCI, 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device; 2 ndThere is a 1-bit indication field in stage SCI, and the 1-bit indication field is used to indicate whether to request resources for data transmission; when the value in the 1-bit indication field is 1, it means to request resources for data transmission, and when the value in the 1-bit indication field is 0, it means that there is no need to request resources for data transmission.

[0681] Among them, the following implementation schemes are also involved. The first implementation scheme: 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, that is, 2 nd stage SCI includes the identifier of the terminal device that sends 2 nd stage SCI, and the identifier of the terminal device that receives 2 nd stage SCI; alternatively, the first terminal device sends the third information to the second terminal device, and the third information is used to indicate the identifier of the first terminal device (at this time, the third information and the fourth information are the same information). Thus, the second terminal device knows that the receiving end of the scheduling information is the first terminal device, and knows that the using end of the data transmission resources is the first terminal device.

[0682] 2 nd stage SCI further includes the identifier of the third terminal device, or the first terminal device sends the fifth information to the second terminal device, and the fifth information is used for the identifier of the third terminal device. Thus, the second terminal device knows that the receiving end of the data is the third terminal device.

[0683] The second implementation scheme: Modify 2 nd stage SCI so that 2 nd stage SCI does not include the identifier of the first terminal device, and at the same time, the first terminal device does not need to send the third information to the second terminal device; thus, the second terminal device does not need to know who the receiving end of the scheduling information is. However, the first terminal device sends the fourth information to the second terminal device, and the fourth information is used to indicate the identifier of the first terminal device; thus, the second terminal device knows that the using end of the data transmission resources is the first terminal device.

[0684] 2 nd stage SCI further includes the identifier of the third terminal device, or the first terminal device sends the fifth information to the second terminal device, and the fifth information is used for the identifier of the third terminal device. Thus, the second terminal device knows that the receiving end of the data is the third terminal device.

[0685] The third implementation scheme: 2 nd stage SCI itself includes the identifier of the first terminal device and the identifier of the second terminal device, that is, 2 nd stage SCI includes the sending 2nd The identifier of the terminal device of stage SCI, and receiving 2 nd The identifier of the terminal device of stage SCI; alternatively, the first terminal device sends the third information to the second terminal device, and the third information is used to indicate the identifier of the first terminal device (in this case, the third information and the fourth information are the same information). Thus, the second terminal device knows that the user of the resource for data transmission is the first terminal device.

[0686] 2 nd The identifier of the third terminal device is further included in stage SCI, or the first terminal device sends the fifth information to the second terminal device, and the fifth information is used for the identifier of the third terminal device. Thus, the second terminal device knows that the recipient of the data is the third terminal device.

[0687] For example (referred to as "Example 2"), the first information is 1 st stage SCI, 1 st There is a preset indication field in stage SCI; when the value in the preset indication field is the first value, it represents the resource for requesting data transmission; when the value in the preset indication field is the second value, it represents the resource that does not need to request data transmission. At this time, the first information indicates the resource for requesting data transmission in an explicit manner. For example, the first terminal device sends 1 st stage SCI; 1 st There is a 1-bit indication field in stage SCI, and the 1-bit indication field is used for the resource of whether to request data transmission; when the 1-bit indication field is 1, it means requesting the resource for data transmission, and when the 1-bit indication field is 0, it means not requesting the resource for data transmission.

[0688] Among them, the following implementation schemes are also involved. The first implementation scheme: The first terminal device sends the third information to the second terminal device, and the third information is used to indicate the identifier of the first terminal device (in this case, the third information and the fourth information are the same information). Thus, the second terminal device knows that the recipient of the scheduling information is the first terminal device, and knows that the user of the resource for data transmission is the first terminal device.

[0689] The first terminal device sends the fifth information to the second terminal device, and the fifth information is used for the identifier of the third terminal device. Thus, the second terminal device knows that the recipient of the data is the third terminal device.

[0690] Second implementation: The first terminal device does not need to send the third information to the second terminal device; thus, the second terminal device does not need to know who the recipient of the scheduling information is. However, the first terminal device sends the fourth information to the second terminal device, and the fourth information is used to indicate the identity of the first terminal device; thus, the second terminal device knows that the user of the data transmission resource is the first terminal device.

[0691] The first terminal device sends the fifth information to the second terminal device, and the fifth information is used for the identity of the third terminal device. Thus, the second terminal device knows that the recipient of the data is the third terminal device.

[0692] Third implementation: The first terminal device sends the third information to the second terminal device, and the third information is used to indicate the identity of the first terminal device (at this time, the third information and the fourth information are the same information). Thus, the second terminal device knows that the user of the data transmission resource is the first terminal device.

[0693] The first terminal device sends the fifth information to the second terminal device, and the fifth information is used for the identity of the third terminal device. Thus, the second terminal device knows that the recipient of the data is the third terminal device.

[0694] For example (referred to as "Example 3"), the first information is 2 nd stage SCI; 2 nd There is a preset bit in the stage SCI; when the preset bit is the first bit sequence, it represents a request for a data transmission resource, and the first bit sequence includes at least one bit; when the preset bit is the second bit sequence, it represents that there is no need to request a data transmission resource, and the second bit sequence includes at least one bit; the first bit sequence and the second bit sequence are different bit sequences. At this time, the first information requests a data transmission resource in an implicit manner. For example, the first terminal device sends 2 nd stage SCI, 2 nd The stage SCI itself includes the identity of the first terminal device and the identity of the second terminal device; 2 nd There is a CRC in the stage SCI. At this time, 1 bit is used for scrambling at 2 nd the last bit of the CRC of the stage SCI; when scrambled with 1, it means a request for a data transmission resource, and when scrambled with 0, it means that there is no need to request a data transmission resource. For example, 2 ndThe CRC of stage SCI is a 24-bit bit sequence 0101 1010 0101 1010 0101 1010. After scrambling with 1, the CRC is 0101 1010 0101 1010 0101 1011, which indicates the resource for requesting data transmission at this time.

[0695] For the rest, refer to the above "Example 1" and will not be elaborated here.

[0696] For example (referred to as "Example 4"), the first information is 1 st stage SCI, 1 st There is a preset bit in stage SCI; when the preset bit is the first bit sequence, it represents the resource for requesting data transmission, and the first bit sequence includes at least one bit; when the preset bit is the second bit sequence, it represents the resource that does not require requesting data transmission, and the second bit sequence includes at least one bit; the first bit sequence and the second bit sequence are different bit sequences. At this time, the first information implicitly indicates the resource for requesting data transmission. For example, the first terminal device sends 1 to the second terminal device st stage SCI; 1 st There is a CRC in stage SCI. At this time, scrambling with 1 is performed on the last bit of the CRC in 1 st For stage SCI, scrambling with 1 indicates the resource for requesting data transmission, and scrambling with 0 indicates the resource that does not require requesting data transmission. For example, 1 st The CRC of stage SCI is a 24-bit bit sequence 0101 1010 0101 1010 0101 1010. After scrambling with 1, the CRC is 0101 1010 0101 1010 0101 1011, which indicates the resource for requesting data transmission at this time.

[0697] For the rest, refer to the above "Example 2" and will not be elaborated here.

[0698] In another example, the first information is MAC layer sidelink control information; the preset indication field in the MAC layer sidelink control information is used to indicate the resource for requesting data transmission, or the preset bit in the MAC layer sidelink control information is used to indicate the resource for requesting data transmission. Among them, the MAC layer sidelink control information can indicate the resource for requesting data transmission in an explicit manner, or the MAC layer sidelink control information can indicate the resource for requesting data transmission in an implicit manner. For example, the MAC layer sidelink control information can be SL MAC CE information.

[0699] For example (referred to as "Example 5"), the first information is SL MAC CE information, and there is a preset indication field in the SL MAC CE information; when the value in the preset indication field is the first value, it represents the resource for requesting data transmission; when the value in the preset indication field is the second value, it represents the resource that does not require requesting data transmission, and the first value and the second value are different. At this time, the first information indicates the resource for requesting data transmission in an explicit manner. For example, the first terminal device sends SL MAC CE information to the second terminal device; there is a preset indication field in the SL MAC CE information, and the preset indication field is used to indicate whether to request the resource for data transmission; when the value in the preset indication field is 1, it means the resource for requesting data transmission, and when the value in the preset indication field is 0, it means the resource that does not require requesting data transmission.

[0700] Among them, the following implementation schemes are also involved. The first implementation scheme: The first terminal device sends the third information to the second terminal device, and the third information is used to indicate the identity of the first terminal device (at this time, the third information and the fourth information are the same information). Thus, the second terminal device learns that the receiver of the scheduling information is the first terminal device, and learns that the user of the resource for data transmission is the first terminal device.

[0701] The first terminal device sends the fifth information to the second terminal device, and the fifth information is used for the identity of the third terminal device. Thus, the second terminal device learns that the receiver of the data is the third terminal device.

[0702] The second implementation scheme: The first terminal device does not need to send the third information to the second terminal device; thus, the second terminal device does not need to know who the receiver of the scheduling information is. However, the first terminal device sends the fourth information to the second terminal device, and the fourth information is used to indicate the identity of the first terminal device; thus, the second terminal device learns that the user of the resource for data transmission is the first terminal device.

[0703] The first terminal device sends the fifth information to the second terminal device, and the fifth information is used for the identity of the third terminal device. Thus, the second terminal device learns that the receiver of the ...

Claims

1. A device-to-device based resource determination method, applied to a second terminal device, characterized in that, The method includes: Receiving first information sent by a first terminal device, where the first information is used to instruct the second terminal device to send auxiliary information, and the first information is further used to instruct a buffer status report message, and the buffer status report message is used to indicate the size of data to be transmitted; Determining the auxiliary information according to the buffer status report message, where the auxiliary information is used to indicate the size and position anchor of an unoccupied resource set; Sending the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in resource selection for data transmission.

2. The method according to claim 1, wherein A preset indication field or preset bit in the first information is used to instruct the second terminal device to send auxiliary information.

3. The method according to claim 1, wherein The first information is specifically used to instruct the second terminal device to send auxiliary information periodically.

4. The method according to claim 3, wherein A first indication field or first bit in the first information is used to indicate the periodic time interval for sending the auxiliary information, and a second indication field or second bit in the first information is used to indicate the time point for sending the auxiliary information.

5. The method according to any one of claims 1-4, characterized in that, The first information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

6. The method according to claim 1, wherein Determining the auxiliary information according to the buffer status report message includes: Determining the size of resources for data transmission according to the buffer status report message; Determining the auxiliary information according to the size of the resources for data transmission.

7. The method according to any one of claims 1-4, 6, characterized in that, The auxiliary information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

8. The method according to any one of claims 1-4 and 6, characterized in that, After sending the auxiliary information to the first terminal device, the method further includes: Receiving data sent by the first terminal device.

9. A device-to-device based resource determination method, applied to a first terminal device, characterized in that, The method includes: Sending first information to a second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information and a buffer status report message, and the buffer status report message is used to indicate the size of data to be transmitted; Receiving the auxiliary information sent by the second terminal device, where the auxiliary information is used to assist the first terminal device in resource selection for data transmission, and the auxiliary information is used to indicate the size and position anchor of an unoccupied resource set; Determining resources for data transmission according to the auxiliary information.

10. The method according to claim 9, wherein A preset indication field or preset bit in the first information is used to instruct the second terminal device to send auxiliary information.

11. The method according to claim 9, wherein The first information is specifically used to instruct the second terminal device to send auxiliary information periodically.

12. The method according to claim 11, wherein A first indication field or first bit in the first information is used to indicate the periodic time interval for sending the auxiliary information, and a second indication field or second bit in the first information is used to indicate the time point for sending the auxiliary information.

13. The method according to any one of claims 9-12, characterized in that, The first information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

14. The method according to any one of claims 9-12, characterized in that, The auxiliary information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

15. The method according to any one of claims 9 - 12, characterized in that, Determining resources for data transmission according to the auxiliary information includes: Selecting resources from the resource set indicated by the auxiliary information as the resources for data transmission, where the auxiliary information is used to indicate an unoccupied resource set; Or determining resources for data transmission according to the resource set indicated by the auxiliary information and the detected resource set.

16. The method according to claim 15, wherein Selecting resources from the resource set indicated by the auxiliary information as the resources for data transmission includes: Randomly selecting resources from the resource set indicated by the auxiliary information as the resources for data transmission; Or selecting the resource with the highest priority from the resources in the resource set indicated by the auxiliary information as the resources for data transmission.

17. The method according to claim 15, wherein Determining resources for data transmission according to the resource set indicated by the auxiliary information and the detected resource set includes: Determining the common resources between the resource set indicated by the auxiliary information and the detected resource set; Selecting resources from the common resources as the resources for data transmission.

18. The method according to any one of claims 9-12, 16-17, characterized in that After determining resources for data transmission according to the auxiliary information, the method further includes: Sending data to the second terminal device or the third terminal device according to the resources for data transmission.

19. A communication device is applied to a second terminal device, and is characterized in that, The communication device includes: A receiving unit, configured to receive first information sent by a first terminal device, where the first information is used to instruct the second terminal device to send auxiliary information and a buffer status report message, and the buffer status report message is used to indicate the size of data to be transmitted; A processing unit, configured to determine the auxiliary information according to the buffer status report message, where the auxiliary information is used to indicate the size and location anchor of an unoccupied resource set; A sending unit, configured to send the auxiliary information to the first terminal device, where the auxiliary information is used to assist the first terminal device in selecting resources for data transmission.

20. The communication device according to claim 19, wherein A preset indication field or preset bit in the first information is used to instruct the second terminal device to send auxiliary information.

21. The communication device according to claim 19, wherein The first information is specifically used to instruct the second terminal device to send auxiliary information periodically.

22. The communication device according to claim 21, characterized in that, A first indication field or first bit in the first information is used to indicate the periodic time interval for sending the auxiliary information, and a second indication field or second bit in the first information is used to indicate the time point for sending the auxiliary information.

23. The communication device according to any one of claims 19-22, characterized in that, The first information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

24. The communication device according to claim 19, characterized in that, The processing unit is specifically configured to: Determine the size of resources for data transmission according to the buffer status report message; Determine the auxiliary information according to the size of the resources for data transmission.

25. The communication device according to any one of claims 19-22 and 24, characterized in that, The auxiliary information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

26. The communication device according to any one of claims 19-22 and 24, characterized in that, The receiving unit is further configured to receive data sent by the first terminal device after the sending unit sends the auxiliary information to the first terminal device.

27. A communication device is applied to a first terminal device, characterized in that, The communication device includes: A sending unit, configured to send first information to a second terminal device, where the first information is used to instruct the second terminal device to send auxiliary information and a buffer status report message, and the buffer status report message is used to indicate the size of data to be transmitted; A receiving unit, configured to receive the auxiliary information sent by the second terminal device, where the auxiliary information is used to assist the first terminal device in resource selection for data transmission, and the auxiliary information is used to indicate the size and position anchor of an unoccupied resource set; A processing unit, configured to determine a resource for data transmission according to the auxiliary information.

28. The communication device according to claim 27, characterized in that A preset indication field or preset bit in the first information is used to instruct the second terminal device to send the auxiliary information.

29. The communication device according to claim 27, wherein The first information is specifically used to instruct the second terminal device to send the auxiliary information periodically.

30. The communication device according to claim 29, characterized in that, A first indication field or first bit in the first information is used to indicate a periodic time interval for sending the auxiliary information, and a second indication field or second bit in the first information is used to indicate a time point for sending the auxiliary information.

31. The communication device according to any one of claims 27 - 30, characterized in that, The first information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

32. The communication device according to any one of claims 27-30, characterized in that The auxiliary information is physical layer sidelink control information, or medium access control layer sidelink control information, or radio resource control layer sidelink control information.

33. The communication device according to any one of claims 27-30, characterized in that, The processing unit is specifically configured to: Select a resource from the resource set indicated by the auxiliary information as the resource for data transmission, where the auxiliary information is used to indicate an unoccupied resource set; Or determine a resource for data transmission according to the resource set indicated by the auxiliary information and the detected resource set.

34. The communication device according to claim 33, wherein When the processing unit is configured to select a resource from the resource set indicated by the auxiliary information as the resource for data transmission, it is specifically configured to: Randomly select a resource from the resource set indicated by the auxiliary information as the resource for data transmission; Or select a resource with the highest priority from the resources in the resource set indicated by the auxiliary information as the resource for data transmission.

35. The communication device according to claim 33, wherein When the processing unit is configured to determine a resource for data transmission according to the resource set indicated by the auxiliary information and the detected resource set, it is specifically configured to: Determine the common resources between the resource set indicated by the auxiliary information and the detected resource set; Select a resource from the common resources as the resource for data transmission.

36. The communication device according to any one of claims 27-30, 34-35, characterized in that, The sending unit is further configured to send data to the second terminal device or the third terminal device according to the resources for data transmission after the processing unit determines the resources for data transmission according to the auxiliary information.

37. A communication device, characterized in that, The device includes a processor and a memory. A computer program is stored in the memory. The processor executes the computer program stored in the memory so that the device executes the method according to any one of claims 1-8, or executes the method according to any one of claims 9-18.

38. A communication device, characterized in that, Comprising: A processor and an interface circuit; The interface circuit is configured to receive code instructions and transmit them to the processor; The processor is configured to run the code instructions to execute the method according to any one of claims 1-8, or execute the method according to any one of claims 9-18.

39. A computer-readable storage medium for storing instructions that, when executed by a processor, implement the method according to any one of claims 1-8, or the method according to any one of claims 9-18.

40. A computer program product comprising program code that, when executed by a processor, implements the method according to any one of claims 1-8, or the method according to any one of claims 9-18.

Images