Communication method and apparatus, readable storage medium, and computer program product

Abstract

A communication method and apparatus, a readable storage medium, and a computer program product, which are used for balancing a network load and improving communication quality. In the present application, a source network apparatus sends first information to a first target network apparatus. The first information is used for requesting a handover of a terminal apparatus from the source network apparatus to the first target network apparatus. The first information comprises indication information of a first resource. The first resource is used by a relay network apparatus to transmit information associated with a handover process. The source network apparatus configures resources for the relay network apparatus, and the resources are used by the relay network apparatus to transmit information associated with handover processes. Thus, resources used by the relay network apparatus to transmit information associated with terminal apparatuses can be dispersed and do not need to excessively concentrated, so that the network load can be balanced, and the peak of the network load is reduced, thereby improving the communication quality.

Description

Communication method, device, readable storage medium and computer program product

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of the People's Republic of China on December 21, 2023, with application number 202311766728.0 and application name "A communication method, device, readable storage medium and computer program product", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of satellite communications, and in particular to a communication method, device, readable storage medium, and computer program product. Background Art

[0004] Currently, the fifth-generation (5G) new radio (NR) technology is evolving from version R18 to R19. At the same time, NR technology has also entered the commercial deployment stage from the standardization stage. The NR standard protocol is a wireless communication technology designed for terrestrial cellular network scenarios, capable of providing users with wireless communication services with ultra-low latency, ultra-reliability, ultra-high speed, and excessive connectivity. Compared to terrestrial communications, non-terrestrial networks (NTN) communications have the advantages of large coverage areas and flexible networking, and can achieve seamless global network coverage. NTN communications involve the use of drones, high-altitude platforms, satellites and other equipment to form networks, providing data transmission, voice communication and other services to user equipment (UE).

[0005] As NTN has grown, the satellite network has grown in size. For example, the satellite network has grown from 66 satellites in the Iridium constellation to 720 satellites in the OneWeb constellation, and has now expanded to the Starlink ultra-dense low Earth orbit (LEO) constellation of over 12,000 satellites.

[0006] In a satellite communication system, the movement of satellite devices may cause group switching (connected UE) or group reselection (idle UE) problems for users in a certain area. Figure 1 shows a schematic diagram of a satellite communication scenario. Figure 1 takes three areas as an example, area #1, area #2 and area #3 shown in Figure 1. Each area can be divided into one or more wave positions. Figure 1 takes a rectangular box as an example to represent a wave position. The UE in a wave position is called a UE cluster, and a UE cluster includes one or more UEs. Please refer to (a) in Figure 1. At time T1, satellite device #1 provides services for UEs in area #1, satellite device #2 provides services for UEs in area #2, and UEs in UE cluster #1 are served by satellite device #2. Time T2 is a time after time T1. Figure 1 (b) shows the positions of each satellite device and UE at time T2. As can be seen from (b) in Figure 1, at time T2, due to the movement of satellite devices #1 and #2, satellite device #2 is no longer able to provide service to the wavelength of UE cluster #1. Instead, satellite device #1 takes over and provides service to UE cluster #1. Therefore, a group handover occurs for the UEs in UE cluster #1. Furthermore, due to the high speed of satellite movement, approximately 7.5 km / s, group handovers occur approximately every few seconds to tens of seconds. In other words, in satellite communication systems, group handovers caused by satellite device movement are commonplace. However, group handovers can lead to concentrated network loads. For example, during a group handover, the source network device needs to transmit relevant information about all terminal devices involved in the group handover to the target network device via a relay network device. It can be seen that current information transmission schemes lead to concentrated network loads, which can even exceed the network's processing capacity, potentially leading to communication failures (such as handover failures and link congestion). Summary of the Invention

[0007] This application provides a communication method, apparatus, readable storage medium, and computer program product for allocating resources to a relay network device, the resources used to transmit information related to a handover process. This solution can balance network load and reduce peak network load, thereby reducing the probability of communication failures and improving communication quality.

[0008] In satellite communications, during a group handoff, terminal devices typically switch within the same or similar time period. Therefore, the source network device must transmit information associated with all terminal devices involved in the group handoff to the target network device at a similar or simultaneous time. This results in an excessive amount of information being transmitted between the source and target network devices, overloading the network and potentially leading to communication failures.

[0009] Based on this, the present application provides an embodiment in which, during a terminal device's network device switching process, the source network device allocates resources to a relay network device. These resources are used by the relay network device to transmit information related to the switching process. As can be seen, in this solution, the resources used by the relay network device to transmit terminal device-related information can be dispersed, rather than being excessively concentrated. This can balance network load, reduce peak network load, and thus improve communication quality.

[0010] In a first aspect, the present application provides a communication method. The communication method can be performed by a source network device. The source network device can be a network device or a chip (or chip system) inside the network device.

[0011] In this solution, a source network device sends first information to a first target network device. The first information is used to request that a terminal device be handed over from the source network device to the first target network device. The first information includes information indicating a first resource. The information transmission path from the source network device to the first target network device includes at least one relay network device, and the first resource is used to transmit information related to the handover process to a relay network device in the at least one relay network device. The source network device sends second information related to the handover process to the first target network device.

[0012] As can be seen, the source network device allocates resources to the relay network device, which is used to transmit information related to the handover process. This solution also allows the relay network device to distribute resources used to transmit terminal device-related information, eliminating the need for excessive concentration. This balances network load, reduces peak load, and improves communication quality.

[0013] In one possible implementation, the indication information of the first resource includes at least one of the following: information for indicating a time period; information for indicating bandwidth resources; information for indicating a transmission rate; information for indicating a quality of service requirement; information for indicating a quality of service experience; information for indicating a location of a relay network device; and information for indicating a polarization mode.

[0014] It can be seen that the parameters of the resources that the source network device can allocate to the relay device can be in various forms, which can improve the flexibility of the solution.

[0015] In one possible implementation, the source network device may allocate resources to terminal devices based on their types. For example, the same resources may be allocated to terminal devices of the same type. For example, a first resource may be used to transmit information related to a handover process for a terminal device of the first type. Alternatively, the first resource may be allocated by the source network device to the terminal device of the first type, and information related to the handover process for the terminal device of the first type may be transmitted via the first resource.

[0016] The source network device can classify terminal devices into types based on various information, such as at least one of the terminal device's priority, terminal device capabilities, terminal device's quality of service requirement, and terminal device's quality of service experience. Alternatively, it can be understood that a first type of terminal device is associated with at least one of the terminal device's priority, terminal device capabilities, terminal device's quality of service requirement, and terminal device's quality of service experience.

[0017] By classifying terminal devices by type, resources can be allocated to different types of terminal devices based on their type. The granularity of resource allocation can be based on the terminal device type. This prevents excessively small resource allocation granularity, which reduces resource allocation complexity. Furthermore, the limited granularity of resource allocation facilitates load balancing. Furthermore, by allocating resources based on terminal device type, the source network device can better match the allocated resources to the actual needs of the terminal device, thereby ensuring satisfactory communication service.

[0018] In one possible implementation, an information transmission path from a source network device to a first target network device includes multiple relay network devices. The first information includes indicative information of multiple first resources. The multiple relay network devices are associated with one of the multiple first resources. The two first resources associated with two of the multiple relay network devices partially overlap or do not overlap. Because the two relay network devices transmit the first information in a sequential order, the source network device can allocate two first resources to different relay network devices, respectively. The two first resources partially overlap or do not overlap. The resource allocation method in this solution better matches actual information transmission conditions, thereby optimizing the overall performance of the communication system.

[0019] In one possible implementation, the first information further includes identification information of a relay network device associated with a first resource among the multiple first resources. Thus, when the source network device allocates the first resource to each of the multiple relay network devices, each relay network device can identify its corresponding first resource based on the identification information of the relay network device associated with the first resource.

[0020] In one possible implementation, the first information further includes: identification information of the first target network device and / or path information from the source network device to the first target network device. Thus, if this scenario applies to a multi-hop scenario, i.e., if there is at least one relay network device between the source network device and the first target network device, the relay network device can determine the next hop information based on this information.

[0021] In one possible implementation, the first information also includes latency information from the source network device to the first destination network device. This allows the relay network device and / or the first destination network device to understand the latency information, thereby establishing an optimal transmission path. This information can assist in subsequent data transmission and reduce end-to-end communication latency.

[0022] In one possible implementation, the first information may include information indicating a transmission mode. The transmission modes in the embodiments of the present application may include a first transmission mode and a second transmission mode. The first transmission mode refers to the relay network device relaying and forwarding information and requiring access to a portion of the information. The second transmission mode refers to the relay network device relaying and forwarding information but not requiring access to the information.

[0023] For example, the first information includes information indicating that the relay network device uses a first transmission mode for transmitting the first information. The first transmission mode includes the relay network device relaying and forwarding the first information and obtaining information indicating a first resource from the first information. The relay network device may determine, based on protocol definitions or negotiated rules, that the content in the first information to be obtained is information indicating the first resource.

[0024] In another possible implementation, the first information further includes information for instructing at least one relay network device to obtain the content carried by the first field of the first information, where the first field includes a field in the first information that carries information indicating the first resource. With this solution, the source network device can flexibly indicate information to be obtained by the relay network device, such as information indicating the first resource, and may also include other information.

[0025] In one possible implementation, a source network device may receive a first handover response message from a first target network device. The first handover response message is a response message to the first message, and the first handover response message includes information indicating that the relay network device uses a second transmission mode, where the second transmission mode instructs the relay network device to relay and forward the first handover response message. The relay network device may relay and forward the first handover response message without obtaining the content of the first handover response message.

[0026] In one possible implementation, the second information further includes: information for indicating that the transmission mode of the relay network device is a second transmission mode, and the second transmission mode instructs the relay network device to relay and forward the second information. The relay network device can relay and forward the second information without obtaining the content of the second information. For example, the second information includes: a handover (HO) acknowledgment, a sequence number (SN) status transfer, and / or a UE context release.

[0027] In one possible implementation, the first information is further used to request that the terminal device be handed over from the source network device to the second target network device. The first information also includes information indicating a second resource, where the second resource is used by a relay network device in at least one relay network device to transmit information associated with the handover process to the second target network device. The source network device sends third information to the second target network device, where the third information is information associated with the handover process. In this way, the relay network device can send the third information using the second resource. Through this solution, the source network device can configure resources for different target network devices separately, and the relay network device can send information associated with the handover process to different target network devices using different resources. In this process, the resources occupied by the information sent to different target network devices can be differentiated, thereby further balancing the network load.

[0028] In one possible implementation, the first information further includes: information indicating the second destination network device; information indicating the information transmission path from the source network device to the second destination network device; and information indicating a relay network device in the information transmission path from the source network device to the second destination network device. In this way, the relay network device can determine the next hop of the path between the source network device and the second destination network device.

[0029] In one possible implementation, a source network device receives second handover response information from a second target network device. The second handover response information is a response to the first information. The second handover response information includes information indicating that a transmission mode of the relay network device is a second transmission mode. The second transmission mode instructs the relay network device to relay and forward the second handover response information. The relay network device can relay and forward the second handover response information without obtaining content in the second handover response information.

[0030] In a possible implementation, the first information also includes: context information of the terminal device. The first information also includes information for indicating the following: a relay network device in at least one relay network device needs to obtain the context information of the terminal device from the first information. The context information of the terminal device in this application may include, for example, at least one of the following: an identifier of the terminal device, an access mode, a status, bearer-related information, security information, capability information, and session information. In this way, the relay network device can obtain the context information of the terminal device, and subsequently when the terminal device needs to re-establish a link, it can use the relay network device that pre-stores the context information of the terminal device to establish a link, thereby speeding up the link establishment and subsequently shortening the duration of the communication failure.

[0031] In one possible implementation, the first information also includes identification information of the relay network device for which the context information of the terminal device needs to be obtained. This eliminates the need for each relay network device to obtain the context information of the terminal device, thereby reducing the amount of information stored by the relay network device and alleviating the storage space occupied by the relay network device.

[0032] In one possible implementation, the first resource is associated with at least one of the following: mobile interruption time information of the terminal device; the uplink service arrival rate of the terminal device; the downlink service arrival rate of the terminal device; and the type of the terminal device. The source network device allocates resources based on this information, thereby more closely matching the allocated resources with information such as the terminal device's services. Subsequently, when information related to the handover process corresponding to the terminal device is transmitted using these resources, it can more closely match the actual service needs of the terminal device.

[0033] In a second aspect, the present application provides a communication method. The communication method can be performed by a terminal device. The terminal device can be a terminal device or a chip (or chip system) inside the terminal device.

[0034] In this solution, the terminal device may obtain fourth information, which includes at least one of the terminal device's priority, terminal device capabilities, terminal device's quality of service requirements, and terminal device's quality of service experience. The terminal device may send the fourth information to the source network device, where the fourth information is used by the source network device to determine a first resource. The information transmission path from the source network device to the first target network device includes at least one relay network device, and the first resource is used to transmit information related to the handover process to a relay network device in the at least one relay network device.

[0035] The fourth information can be used to assist the source network device in allocating resources to the relay network device. These resources are used by the relay network device to transmit information related to the handover process. This solution allows the resources used by the relay network device to transmit terminal device-related information to be dispersed, rather than concentrated. This can balance network load, reduce peak network load, and thus improve communication quality. Furthermore, allocating resources based on the fourth information can better align them with the actual service needs of the terminal device, thereby optimizing the overall performance of the communication system.

[0036] In one possible implementation, the indication information of the first resource includes at least one of the following: information for indicating a time period; information for indicating bandwidth resources; information for indicating a transmission rate; information for indicating a quality of service requirement; information for indicating a quality of service experience; information for indicating a location; and information for indicating a polarization mode.

[0037] For the relevant content about the first resource, please refer to the relevant description of the first aspect and will not be repeated here.

[0038] In one possible implementation, the terminal device receives fifth information indicating a relay network device storing context information of the terminal device. Based on the fifth information, the terminal device determines an information transmission path between the terminal device and at least one relay network device. For related details and beneficial effects, please refer to the description of the first aspect and will not be repeated here.

[0039] In a third aspect, the present application provides a communication method. The communication method can be performed by a relay network device. The relay network device can be a network device or a chip (or chip system) inside the network device.

[0040] The relay network device is at least one relay network device included in an information transmission path from a source network device to a first target network device. The relay network device receives first information from the source network device, the first information being used to request handover of a terminal device from the source network device to the first target network device. The first information includes information indicating a first resource, which is used by the relay network device to transmit information related to the handover process. The relay network device obtains the information indicating the first resource from the first information. The relay network device sends the first information to the first target network device. The relay network device receives second information from the source network device, the second information being information related to the handover process. The relay network device sends the second information to the first target network device using the first resource.

[0041] The source network device allocates resources to the relay network device, which is used to transmit information related to the handover process. This solution allows the relay network device to distribute resources used to transmit terminal device-related information, eliminating the need for excessive concentration. This balances network load, reduces peak load, and improves communication quality.

[0042] In a possible implementation manner, the content included in the indication information of the first resource can refer to the relevant description of the first aspect above and will not be repeated here.

[0043] In one possible implementation, the first resource is used by the relay network device to transmit information associated with a handover process of a first type of terminal device. The first type of terminal device is associated with at least one of: a priority of the terminal device, a capability of the terminal device, a quality of service requirement of the terminal device, and a quality of service experience of the terminal device.

[0044] In one possible implementation, an information transmission path from a source network device to a first target network device includes multiple relay network devices, the first information includes indication information of multiple first resources, the multiple relay network devices are associated with one first resource among the multiple first resources, and the two first resources associated with two relay network devices among the multiple relay network devices partially overlap or do not overlap.

[0045] In a possible implementation manner, the content included in the first information can refer to the relevant description of the first aspect above and will not be repeated here.

[0046] In one possible implementation, a relay network device receives first handover response information from a first target network device. The relay network device sends the first handover response information to the source network device, where the first handover response information is response information to the first information and includes information indicating that the relay network device uses a second transmission mode, where the second transmission mode instructs the relay network device to relay and forward the first handover response information.

[0047] In a possible implementation manner, the content included in the second information can refer to the relevant description of the first aspect above and will not be repeated here.

[0048] In one possible implementation, the first information is further used to request handover of the terminal device from the source network device to the second target network device. The first information also includes indicative information of a second resource, where the second resource is used by the relay network device to transmit information related to the handover process to the second target network device. The relay network device obtains the indicative information of the second resource from the first information. The relay network device receives third information from the source network device. The relay network device sends third information related to the handover process to the second target network device using the second resource.

[0049] In one possible implementation, the relay network device receives second handover response information from the second target network device. The relay network device sends the second handover response information to the source network device, where the second handover response information is response information to the first information and includes information indicating that the relay network device uses a second transmission mode, where the second transmission mode instructs the relay network device to relay and forward the second handover response information.

[0050] In a possible implementation, the first information further includes: context information of the terminal device. The first information further includes information indicating that the relay network device needs to obtain the context information of the terminal device from the first information. The relay network device obtains the context information of the terminal device from the first information.

[0051] In a possible implementation manner, the first information further includes: identification information of the relay network device for which the context information of the terminal device needs to be obtained.

[0052] In a possible implementation, the first resource is associated with at least one of the following: mobile interruption time information of the terminal device; uplink service arrival rate of the terminal device; downlink service arrival rate of the terminal device; type of the terminal device.

[0053] In one possible implementation, if the relay network device determines that the first path is unusable for transmitting the first information, it determines a second path and transmits the first information to the first target network device via the second path. In this solution, if the relay network device determines that communication via the first path has failed, it can proactively switch paths, thereby accelerating information transmission.

[0054] In a fourth aspect, the present application provides a communication method. The communication method can be performed by a first target network device. The first target network device can be a network device or a chip (or chip system) inside the network device.

[0055] The first target network device receives first information from the source network device. The first information is used to request handover of the terminal device from the source network device to the first target network device. The information transmission path from the source network device to the first target network device includes at least one relay network device. The first information includes information indicating a first resource, and the first resource is used for the relay network device to transmit information related to the handover process. The first target network device receives second information from the source network device, and the second information is information related to the handover process.

[0056] The source network device allocates resources to the relay network device, which is used to transmit information related to the handover process. Correspondingly, the first target network device receives information related to the handover process using the corresponding resources. This solution allows the relay network device to distribute resources used to transmit terminal device-related information, eliminating the need for excessive concentration. This balances network load, reduces peak load, and improves communication quality.

[0057] In one possible implementation, the first target network device sends a first switching response message to the source network device, where the first switching response message is response information of the first message, and the first switching response message includes information for indicating that the transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the first switching response message.

[0058] For relevant descriptions about the first resource and the first information, please refer to the content of the first aspect mentioned above and will not be repeated here.

[0059] In a fifth aspect, a communication device is provided, which may be the aforementioned terminal device, source network device, relay network device, or first target network device. The communication device may include a communication unit and a processing unit to perform any of the above-mentioned first to fourth aspects, or any possible implementation of the first to fourth aspects. The communication unit is used to perform functions related to sending and receiving. The communication unit may be referred to as a transceiver unit. Optionally, the communication unit includes a receiving unit and a sending unit. In one design, the communication device is a communication chip, the processing unit may be one or more processors or processor cores, and the communication unit may be an input / output circuit, an input / output interface, or an antenna port of the communication chip.

[0060] In another design, the communication unit may be a transmitter and a receiver, or the communication unit may be a transmitter and a receiver.

[0061] Optionally, the communication device further includes modules that can be used to execute any one of the first to fourth aspects above, or execute any possible implementation of the first to fourth aspects.

[0062] In a sixth aspect, a communication device is provided, which may be the aforementioned terminal device, source network device, relay network device, or first target network device. The communication device may include a processor and a memory to perform any of the aforementioned aspects from the first to the fourth aspect, or to perform any possible implementation of the aspects from the first to the fourth aspect. Optionally, a transceiver is further included, the memory is used to store a computer program or instruction, and the processor is used to call and execute the computer program or instruction from the memory. When the processor executes the computer program or instruction in the memory, the communication device performs any of the aforementioned aspects from the first to the fourth aspect, or to perform any possible implementation of the aspects from the first to the fourth aspect.

[0063] Optionally, there are one or more processors and one or more memories.

[0064] Optionally, the memory may be integrated with the processor, or the memory may be provided separately from the processor.

[0065] Optionally, the transceiver may include a transmitter (transmitter) and a receiver (receiver).

[0066] In a seventh aspect, a communication device is provided. The communication device may be the aforementioned terminal device, source network device, relay network device, or first destination network device. The communication device may include a processor to perform any of the aforementioned aspects 1 to 4, or any possible implementation of the aspects 1 to 4. The processor is coupled to a memory. Optionally, the communication device further includes a memory. Optionally, the communication device further includes a communication interface, and the processor is coupled to the communication interface.

[0067] In one implementation, when the communication device is a terminal device, a source network device, a relay network device, or a first target network device, the communication interface may be a transceiver or an input / output interface. Alternatively, the transceiver may be a transceiver circuit. Alternatively, the input / output interface may be an input / output circuit.

[0068] In another implementation, when the communication device is a chip or a chip system, the communication interface may be an input / output interface, an interface circuit, an output circuit, an input circuit, a pin, or related circuits on the chip or chip system. The processor may also be embodied as a processing circuit or a logic circuit.

[0069] In an eighth aspect, a system is provided, which includes the above-mentioned terminal device.

[0070] In a possible implementation, the system may further include a source network device, a relay network device, and a first target network device.

[0071] In the ninth aspect, a computer program product is provided, which includes: a computer program (also referred to as code, or instructions), which, when executed, enables the computer to execute any one of the above-mentioned first to fourth aspects, or any possible implementation of the first to fourth aspects.

[0072] In the tenth aspect, a computer-readable storage medium is provided, which stores a computer program (also referred to as code, or instructions). When the computer program is run on a computer, the computer executes any one of the above-mentioned first to fourth aspects, or executes any possible implementation of the first to fourth aspects.

[0073] In an eleventh aspect, a processing device is provided, comprising: an interface circuit and a processing circuit. The interface circuit may include an input circuit and an output circuit. The processing circuit is configured to receive signals via the input circuit and transmit signals via the output circuit, thereby implementing any of the first to fourth aspects, or any possible implementation of the first to fourth aspects.

[0074] In a specific implementation, the processing device may be a chip, the input circuit may be an input pin, the output circuit may be an output pin, and the processing circuit may be a transistor, a gate circuit, a trigger, or various logic circuits. The input signal received by the input circuit may be, for example, but not limited to, received and input by a receiver, and the signal output by the output circuit may be, for example, but not limited to, output to and transmitted by a transmitter. The input circuit and the output circuit may be the same circuit, which functions as an input circuit and an output circuit at different times. This application does not limit the specific implementation of the processor and various circuits.

[0075] In one implementation, when the communication device is a terminal device, a source network device, a relay network device, or a first target network device, the interface circuit may be a radio frequency processing chip in the terminal device, the source network device, the relay network device, or the first target network device, and the processing circuit may be a baseband processing chip in the terminal device, the source network device, the relay network device, or the first target network device.

[0076] In another implementation, the communication device may be a component of a terminal device, a source network device, a relay network device, or a first target network device, such as an integrated circuit product such as a system-on-chip (SoC) or a communication chip. The interface circuit may be an input / output interface, interface circuit, output circuit, input circuit, pin, or related circuit on the chip or chip system. The processing circuit may be a logic circuit on the chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] FIG1 is a schematic diagram of a satellite beam coverage area;

[0078] FIG2A is a schematic diagram of a network architecture of a communication system applicable to an embodiment of the present application;

[0079] FIG2B is a schematic diagram of a network architecture of another communication system applicable to an embodiment of the present application;

[0080] FIG3A is a schematic diagram of a possible operating mode of a satellite applicable to an embodiment of the present application;

[0081] FIG3B is a schematic diagram of another possible operating mode of a satellite applicable to an embodiment of the present application;

[0082] FIG4 is a schematic diagram of a possible flow chart of a communication method provided in an embodiment of the present application;

[0083] FIG5 is a schematic diagram of the structure of first information provided in an embodiment of the present application;

[0084] FIG6 is a schematic diagram of a possible flow chart of a communication method provided in an embodiment of the present application;

[0085] FIG7 is a schematic diagram of a possible flow chart of a communication method provided in an embodiment of the present application;

[0086] FIG8 is a schematic diagram of a possible architecture of a communication system provided in an embodiment of the present application;

[0087] FIG9 is a schematic diagram of a possible flow chart of a communication method provided in an embodiment of the present application;

[0088] FIG10 is a schematic diagram of a possible architecture of a communication system provided in an embodiment of the present application;

[0089] FIG11 is a schematic diagram of a possible flow chart of a communication method provided in an embodiment of the present application;

[0090] FIG12 is a schematic diagram of a possible architecture of a communication system provided in an embodiment of the present application;

[0091] FIG13 is a schematic diagram of a possible structure of a communication device provided in an embodiment of the present application;

[0092] FIG14 is a schematic diagram of a possible structure of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0093] The technical solution of the present application can be applied to non-terrestrial network (NTN) systems such as satellite communication systems, high altitude platform station (HAPS) communications, and drones, for example, integrated communication and navigation (IcaN) systems, global navigation satellite systems (GNSS) and ultra-dense low-orbit satellite communication systems. Satellite communication systems can be integrated with traditional mobile communication systems. For example, mobile communication systems can be fourth-generation (4G) communication systems (for example, long-term evolution (LTE) systems), worldwide interoperability for microwave access (WiMAX) communication systems, fifth-generation (5G) communication systems (for example, new radio (NR) systems), and future mobile communication systems.

[0094] Figures 2A and 2B illustrate exemplary network architecture diagrams of several communication systems applicable to embodiments of the present application. These communication systems may include satellites, network equipment, and terminal devices. These systems may also include gateways and core network equipment. Figures 2A and 2B illustrate exemplary converged network architectures for NTNs and terrestrial networks. These are described below with reference to the accompanying figures.

[0095] (1) Satellite.

[0096] The satellite may be a highly elliptical orbiting (HEO) satellite, a GEO satellite, a medium earth orbit (MEO) satellite, or a low earth orbit (LEO) satellite. The embodiments of the present application do not limit the operating mode of the satellite. For example, the operating mode of the satellite may be a transparent mode, a regenerative mode, or a network controlled repeater (NCR). FIG2A illustrates the operating mode of the satellite as the transparent mode, and FIG2B illustrates the operating mode of the satellite as the regenerative mode.

[0097] When a satellite operates in transparent mode, it performs relay functions. A gateway performs the functions of a network device (such as a base station) or some of them. In this case, the gateway can be considered a network device (such as a base station). Alternatively, the network device (such as a base station) can be deployed separately from the gateway. In this case, the feeder link latency includes both the satellite-to-gateway and gateway-to-gNB delays. The transparent mode discussed below uses the case where the gateway and gNB are located together or close together. For scenarios where the gateway and gNB are farther apart, the feeder link latency is simply the sum of the satellite-to-gateway and gateway-to-gNB delays.

[0098] When the satellite operates in regenerative mode, it has data processing capabilities, the functions of a network device (such as a base station) or partial functions of a network device (such as a base station). At this time, the satellite can be regarded as a network device (such as a base station).

[0099] Satellites can communicate wirelessly with terminals by broadcasting communication signals and navigation signals. Optionally, each satellite can provide communication services, navigation services, and positioning services to terminal devices through multiple beams. For example, each satellite uses multiple beams to cover the service area, and the relationship between different beams can be one or more of time division, frequency division, and space division. Satellites can also operate in earth-fixed, quasi earth-fixed, satellite-fixed, or earth-moving modes. Among them, the earth-fixed mode is usually used for GEO satellites, and the quasi earth-fixed mode is usually used for LEO / MEO satellites.

[0100] Among them, the quasi-Earth fixed mode, also known as the staring mode, refers to dynamically adjusting the satellite's beam pointing so that it continuously serves a certain physical area over a period of time. Figure 3A exemplifies a schematic diagram of a possible operating mode of a satellite. As shown in Figure 3A, over a period of time (such as time t0, time t1, and time t2), the satellite dynamically adjusts the beam pointing so that the beam approximately covers the same area on the ground. In practice, due to the accuracy of the beam pointing and the distortion of the beam projection on the ground at different incident angles, the coverage area of ​​the staring beam may have a certain degree of jitter with respect to time.

[0101] Satellite fixed mode means that the satellite's beam moves with the satellite, and the physical area it serves also changes continuously. Figure 3B illustrates a possible satellite operating mode. As shown in Figure 3B, over a period of time (e.g., time t0, time t1, and time t2), the satellite beam's coverage area moves with the satellite.

[0102] (2) Gateway.

[0103] A gateway (also known as a ground station, earth station, gateway, or gateway station) can be used to connect satellites to terrestrial network equipment (such as terrestrial base stations). One or more satellites can be connected to one or more terrestrial network equipment (such as terrestrial base stations) through one or more gateways, without limitation.

[0104] The link between the satellite and the terminal is called the service link, and the link between the satellite and the gateway is called the feeder link. Network equipment can be deployed separately from the gateway, so the feeder link latency can include both the satellite-to-gateway and gateway-to-network equipment latency.

[0105] (3) Network equipment.

[0106] The network devices in the embodiments of the present application may include network devices deployed on satellites (such as satellite base stations), network devices deployed on gateways, and network devices deployed on the ground (such as ground base stations).

[0107] The network devices involved in the embodiments of the present application may be radio access network (RAN) nodes. The RAN may be an evolved universal terrestrial radio access (E-UTRA) system, a NR system, or a future radio access system defined in the 3rd Generation Partnership Project (3GPP). The RAN may also include two or more of the above-mentioned different radio access systems. The RAN may also be an open RAN (O-RAN).

[0108] A RAN node, also known as a radio access network device, RAN entity, or access node, facilitates wireless access to a communication system by a terminal. In one application scenario, a RAN node can be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next-generation base station in a next-generation NodeB (gNB) in a fifth-generation (5G) mobile communication system, or a base station in a future mobile communication system. A RAN node can be a macro base station, a micro base station, an indoor station, a relay node, or a donor node.

[0109] In another application scenario, multiple RAN nodes can collaborate to help terminals achieve wireless access, with different RAN nodes implementing portions of the base station's functions. For example, a RAN node can be a centralized unit (CU), a distributed unit (DU), or a radio unit (RU). The CU implements the base station's radio resource control protocol and packet data convergence protocol (PDCP) functions, as well as the service data adaptation protocol (SDAP) functions. The DU implements the base station's radio link control layer and medium access control (MAC) layer functions, as well as some or all of the physical layer functions. For detailed descriptions of each of the above protocol layers, please refer to the relevant 3GPP technical specifications. The RU can be used to implement the transmission and reception of radio frequency signals. The CU and DU can be two independent RAN nodes, or they can be integrated into the same RAN node, such as in a baseband unit (BBU). The RU can be included in radio frequency equipment, such as a remote radio unit (RRU) or an active antenna unit (AAU). The CU can be further divided into two types of RAN nodes: CU-control plane and CU-user plane.

[0110] In different systems, RAN nodes may have different names. For example, in an O-RAN system, a CU may be called an open CU (O-CU), a DU may be called an open DU (O-DU), and a RU may be called an open RU (O-RU). The RAN node in the embodiments of the present application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module. For example, the RAN node may be a server loaded with the corresponding software module. The embodiments of the present application do not limit the specific technology and specific device form adopted by the RAN node. For ease of description, the following description takes a base station as an example of a RAN node.

[0111] (4) Core network equipment (CN).

[0112] Core network equipment is a device that is installed on the ground and can communicate with NTN equipment in the NTN system. CN equipment is the network element included in the CN part of the mobile communication system. CN equipment can connect terminal equipment to different data networks and perform services such as authentication, billing, mobility management, session management, policy control, and user plane forwarding. CN equipment can be used for current mobile communication systems (such as the 5th generation (5G) th The CN devices in the 5G generation (5G) mobile communication system may also be CN devices in future mobile communication systems. In mobile communication systems of different standards, the names of CN devices with the same function may vary. However, the embodiments of the present application do not limit the specific names of CN devices with each function.

[0113] For example, in the 4th generation (4 th In the 4G (4th generation) mobile communication system (i.e., long term evolution, LTE), the network element responsible for access control, security control, and signaling coordination is the mobility management entity (MME); the network element serving as the local mobility management anchor point is the serving gateway (S-GW); the network element serving as the anchor point for switching to the external data network and responsible for allocating Internet protocol (IP) addresses is the packet data network (PDN) gateway (P-GW); the network element storing user-related data and subscription data is the home subscriber server (HSS); and the network element responsible for policy and charging functions is called the policy and charging rule function (PCRF) network element.

[0114] For example, in a 5G mobile communication system, the core network can be divided into a control plane (CP) and a user plane (UP) according to specific logical functional divisions. The network elements in the CN responsible for control plane functions can be collectively referred to as control plane network elements, and the network elements responsible for user plane functions can be collectively referred to as user plane network elements. Specifically, in the user plane, the network element that serves as the interface to the data network and is responsible for user plane data forwarding and other functions is the user plane function (UPF) network element. In the control plane, the network element responsible for access control and mobility management functions is called the access and mobility management function (AMF) network element; the network element responsible for session management and control policy execution is called the session management function (SMF) network element; the network element responsible for managing subscription data, user access authorization, and other functions is called the unified data management (UDM) network element; the network element responsible for billing and policy control functions is called the policy control function (PCF) network element; and the application function (AF) network element is responsible for transmitting the application side's requirements to the network side.

[0115] (5)Terminal.

[0116] A terminal is a device with wireless transceiver capabilities that can send signals to a base station or receive signals from a base station. A terminal may also be referred to as a terminal device, user equipment (UE), mobile station, mobile terminal, etc. Terminals can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, etc. A terminal can be a mobile phone, tablet computer, computer with wireless transceiver capabilities, wearable device, vehicle, airplane, ship, robot, robotic arm, smart home device, etc. The embodiments of this application do not limit the specific technology and specific device form adopted by the terminal.

[0117] The embodiments of the present application may also be applicable to other communication system architectures, such as an air-to-ground (ATG) communication system, which includes at least one network device and at least one high-altitude terminal. Examples of high-altitude terminals include high-altitude aircraft and onboard terminals. The satellites in Figures 2A and 2B may also be replaced with other relay devices, such as high altitude platform stations (HAPS) and other NTN devices. The communication system shown in Figures 2A or 2B is provided as an example and does not limit the communication systems to which the methods provided in the embodiments of the present application are applicable.

[0118] Based on the contents shown in Figures 2A, 2B, 3A and 3B and the other contents mentioned above, Figure 4 exemplarily shows a possible flow chart of a communication method provided by an embodiment of the present application. For ease of understanding, Figure 4 takes the interaction between a terminal device, a source network device, a first target network device and a relay network device as an example for introduction. The terminal device in the embodiment of the present application can be a terminal in Figure 2A, 2B, 3A or 3B or a chip system inside the terminal. The source network device and the first target network device can be a network device in Figure 2A, 2B, 3A or 3B or a chip system inside the network device. At least one relay network device can be included between the source network device and the first target network device. The relay network device can be a satellite in Figure 2A, 2B, 3A or 3B or a chip system inside a satellite, or it can be a ground-deployed network device. Multiple relay network devices may be included between the source network device and the first target network device, and the multiple relay network devices may all belong to a satellite or a chip system within a satellite; or some of the multiple relay network devices belong to a satellite or a chip system within a satellite, and another part belongs to a ground-deployed network device. The ground-deployed network device involved in the embodiments of the present application is, for example, a ground-deployed network device or a chip system within a network device as shown in Figures 2A, 2B, 3A, or 3B.

[0119] The following is an introduction with reference to FIG4 .

[0120] Step 401: The terminal device sends fourth information to the source network device.

[0121] Correspondingly, the source network device receives the fourth information.

[0122] In step 401, the terminal device may obtain fourth information and send the fourth information to the source network device. The fourth information is used by the source network device to determine the first resource. The first resource is used by the relay network device to transmit information related to the handover process.

[0123] The fourth information includes information associated with the terminal device, for example, the fourth information may include at least one of the priority of the terminal device (information A1), the capability of the terminal device (information A2), the service quality requirement of the terminal device (information A3), and the service quality experience of the terminal device (information A4).

[0124] Information A1, priority of terminal device.

[0125] The priority of the terminal device includes, for example, a service level agreement (SLA) of the terminal device and / or a category of the terminal device (UE category).

[0126] Information A2: Capabilities of the terminal device.

[0127] The capabilities of the terminal device may include, for example, at least one of: a power level of the terminal device, an antenna type, a terminal storage size, a frequency point supported by the terminal, or a polarization mode supported by the terminal.

[0128] Information A3: Quality of service (QoS) requirements of the terminal device.

[0129] The quality of service requirement of the terminal device may include, for example, at least one of delay jitter, throughput, delay, and reliability of the service corresponding to the terminal device.

[0130] Information A4, quality of experience (QoE) of the terminal device.

[0131] The service quality experience of the terminal device may include, for example, at least one of the service delay actually felt by the terminal device, user throughput, delay jitter, service freeze, and service interruption.

[0132] In one possible implementation, terminal devices may be classified based on at least one of the above-mentioned information A1, information A2, information A3, and information A4. For example, terminal devices with high priority belong to the first type, and terminal devices with low priority belong to the second type. Another example is that terminal devices with a power level above a specified value belong to the first type. It can also be understood that terminal devices of the first type are associated with at least one of the following: the priority of the terminal device, the capability of the terminal device, the quality of service requirement of the terminal device, and the quality of service experience of the terminal device. The source network device may allocate the same resources to a class of terminal devices (terminal devices of the same type). The source network device may allocate different resources to different classes of terminal devices. For example, resource #1 is allocated to a terminal device of the first type, and resource #2 is allocated to a terminal device of the second type. Resource #1 and resource #2 may partially overlap or not overlap. There may be multiple terminal devices of the first type. For one or more terminal devices of the first type, the relay device may transmit information associated with the handover process of these terminal devices on resource #1; for one or more terminal devices of the second type, the relay device may transmit information associated with the handover process of these terminal devices on resource #2.

[0133] In another possible implementation, the first resource may not be determined based on the fourth information, but may be determined by the source network device. In this case, step 401 may not be performed.

[0134] Step 402: The source network device sends first information.

[0135] Correspondingly, the relay network device receives the first information.

[0136] In embodiments of the present application, one or more relay network devices may be located between the source network device and the first target network device. The relay network device in embodiments of the present application may be adjacent to or not adjacent to the source network device. The relay network device may be the first information received from the source network device or from another relay network device.

[0137] The first information is used to request to switch the terminal device from the source network device to the first target network device.

[0138] The first information may be carried in a handover (HO) request message.

[0139] The first information may include some information, for example, the first information may include at least one of indication information of the first resource (information B1), transmission mode indication information (information B2), identification information (information B3) and delay information of the source network device and the first target network device (information B4).

[0140] Information B1: indication information of the first resource.

[0141] The first resource is used for a relay network device in at least one relay network device to transmit information associated with a handover process. In one possible implementation, the first resource may correspond to one or more terminal devices, for example, the first resource may correspond to a class of terminal devices. In this way, the relay network device may transmit information associated with a handover process corresponding to the terminal device (or the class of terminal devices) using the first resource.

[0142] In an embodiment of the present application, information associated with the handover process may include, for example, at least one of handover signaling, user context information, and user data forwarding. The handover signaling may include, for example, signaling involved in the handover process, such as measurement reports, RRC reconfiguration, handover requests, handover responses, SN status transfers, path switch requests, and the like. The context information of the terminal device in the present application may include, for example, at least one of: an identifier of the terminal device, access mode, status, bearer-related information, security information, capability information, and session information.

[0143] In the embodiment of the present application, the indication information of the first resource includes at least one of the following information B1.1, information B1.2, information B1.3, information B1.4, information B1.5, information B1.6, information B1.7 and information B1.8.

[0144] Information B1.1 is used to indicate the time period.

[0145] For example, if the information indicating the time period is [t1, t2], then the information indicates that the time domain resource in the first resource is the time period [t1, t2], and the relay network device can transmit information related to the switching process in the time period.

[0146] In one possible implementation, the source network device can allocate different resources to two terminal devices (e.g., two types of terminal devices), such as allocating a time period [t1, t2] to terminal device #1 and a time period [t2, t3] to terminal device #2. The relay network device can transmit information associated with terminal device #1 during the handover process during time period [t1, t2], and the relay network device can transmit information associated with terminal device #2 during the handover process during time period [t2, t3]. It can be seen that in this solution, the source network device can allocate resources to the relay network device, thereby transmitting information associated with multiple terminal devices during the handover process via multiple resources, thereby balancing the network load.

[0147] Information B1.2 is used to indicate bandwidth resources.

[0148] Information B1.3 is used to indicate the transmission rate.

[0149] Information B1.4 is used to indicate service quality requirements.

[0150] Information B1.5 is used to indicate the service quality experience.

[0151] Information B1.6 is used to indicate the location of the relay network device.

[0152] The information used to indicate the position of the relay network device may include, for example: the position of the relay network device (such as a satellite), angles (such as inclination, aperture, etc.), orbital parameters (such as perigee argument, semi-major axis, eccentricity, inclination, right ascension of the ascending node and perigee time) and other information.

[0153] Information B1.7 is used to indicate the polarization mode of the relay network device.

[0154] Information B1.8 is used to indicate bearer information, such as radio bearers for signaling and data.

[0155] In one possible implementation, the first resource is associated with at least one of the following information: mobility interruption time information of the terminal device, i.e., the time during which the terminal cannot transmit data with any network device during the switching process; uplink service arrival rate of the terminal device; downlink service arrival rate of the terminal device; type of the terminal device. It can also be understood that the source network device can allocate resources to the terminal device based on this information. The type of the terminal device can be associated with at least one of the above-mentioned information A1, information A2, information A3, and information A4, and it can also be understood that the source network device can determine the type of the terminal device based on at least one of the information A1, information A2, information A3, and information A4.

[0156] Information B2: transmission mode indication information.

[0157] In the embodiment of the present application, a piece of information (such as the first information) may carry transmission mode indication information, and the transmission mode indication information may indicate the transmission mode (transmission mode) of the information.

[0158] In the embodiment of the present application, the transmission mode includes a first transmission mode and a second transmission mode. The first transmission mode and the second transmission mode may also be referred to as transmission mode A and transmission mode B, respectively. The first transmission mode means that the relay network device relays and forwards the information and needs to obtain part of the content of the information. The second transmission mode means that the relay network device relays and forwards the information. In the second transmission mode, the relay network device does not need to obtain the content of the information being relayed and forwarded; or, the second transmission mode may also be understood as: the relay network device only relays and forwards the information and does not perform other processing on the information.

[0159] Relay forwarding in the embodiment of the present application can be: the relay network device transparently forwards the information (which can also be understood as the relay network device working in the transparent transmission mode), or it can be: the relay network device regenerates and forwards the information (which can also be understood as the relay network device working in the regeneration mode).

[0160] In one possible implementation, the first information includes information indicating that the relay network device uses a first transmission mode for transmitting the first information. Alternatively, the transmission mode indication information in the first information indicates that the transmission mode is the first transmission mode. The first transmission mode includes the relay network device relaying the first information and obtaining information indicating a first resource in the first information.

[0161] In the embodiment of the present application, the resource carried by the indication information of the first resource may be a designated field. When the relay network device determines that the transmission mode of a piece of information is the first transmission mode, it is necessary to further identify the content carried by the designated field. In another possible implementation, the first information may also indicate the field that the relay network device needs to identify. For example, the first information also includes: information for instructing the relay network device to obtain the content carried by the first field of the first information, and the first field includes the field in the first information used to carry the indication information of the first resource. In this way, the relay network device can determine the content carried by the first field based on this information.

[0162] Information B3, identification information.

[0163] Information B3 may include, for example, at least one of: identification information of the relay network device, identification information of the first target network device, and path information from the source network device to the first target network device.

[0164] The relay network device can determine the next hop information through the information B3. Therefore, the solution provided by the embodiment of the present application can be applied to a scenario where there is at least one relay network device between the source network device and the first target network device.

[0165] The source network device may determine path information from the source network device to the first target network device. The path may be determined based on at least one of the following factors: terminal type, terminal capability, service level (SLA), service type, and handover time period. For example, for services of delay-sensitive and / or high-priority terminals, the transmission path may be determined based on a minimum delay criterion; for services of delay-insensitive and / or low-priority terminals, the transmission path may be determined based on an available bandwidth criterion, thereby avoiding network congestion and achieving load balancing.

[0166] In one possible implementation, for one or more (for example, the same type) terminal devices, multiple relay network devices between the source network device and the first target network device may correspond to the same first resource, and the multiple relay network devices may transmit information associated with the terminal device during the switching process on the same first resource.

[0167] In another possible implementation, the information transmission path from the source network device to the first target network device includes multiple relay network devices, the first information includes indicative information of multiple first resources, the multiple relay network devices are associated with one of the multiple first resources, and the two first resources associated with two of the multiple relay network devices may partially overlap or not overlap. In this implementation, the first information may also include identification information of the relay network device corresponding to each first resource. In this implementation, for one or more (e.g., the same type of) terminal devices, the source network device can allocate different relay network devices with different resources, thereby achieving more fine-grained management of resources.

[0168] Information B4, delay information between the source network device and the first target network device.

[0169] The first message carries information B4, which enables the relay network device and / or the first target network device to understand the delay information, thereby establishing a better transmission path, assisting the transmission of subsequent data based on this information, and reducing the end-to-end communication delay.

[0170] In addition to the above-mentioned information B1, information B2, information B3 and information B4, the first information may also include some other information. Figure 5 exemplifies a structural diagram of a possible first information. As shown in Figure 5, the first information includes information B2 and information B3. As shown in Figure 5, the first information may also include information for indicating whether the first information belongs to a control protocol data unit (PDU) or a data PDU. The first information also includes SN information, which is used to sort the segmented PDUs. The first information also includes load size indication information, which is used to indicate the size of the load of the first information. The first information may also include control plane or user plane data.

[0171] FIG5 shows a possible example of the first information, wherein the first information may include more or less information, and the order of each content in the first information may also be changed.

[0172] Step 403: The relay network device obtains indication information of the first resource from the first information.

[0173] In one possible implementation, after receiving the first information, the relay network device may determine, based on protocol provisions or preset rules, that the indication information for obtaining the first resource is required. In another possible implementation, the first information may carry indication information for the first transmission mode, and the relay network device determines, based on this information, that the indication information for obtaining the first resource is required from the first information.

[0174] Step 404: The relay network device sends the first information.

[0175] Correspondingly, the first target network device receives the first information.

[0176] In the embodiments of the present application, the relay network device and the first target network device may be adjacent or non-adjacent. The first target network device may receive the first information from the relay network device or from another relay network device. The embodiments of the present application are described using a relay network device as an example. The solutions implemented by other relay network devices are similar and will not be described in detail.

[0177] Step 405: The source network device sends second information.

[0178] Correspondingly, the relay network device receives the second information.

[0179] The second information is information related to the handover process, for example, the second information is handover signaling, user context information, user data forwarding, or SN status transfer information.

[0180] Step 406: The relay network device sends the second information via the first resource.

[0181] Correspondingly, the first target network device receives the second information.

[0182] In one possible implementation, when a time domain resource in a first resource expires, the relay network device may release the first resource. For example, the time domain resource in the first resource includes a time period [t1, t2]. The relay network device may release the first resource after a time (t2 + t_offset), where t_offset is greater than or equal to 0.

[0183] As can be seen from the solution provided in Figure 4, on the one hand, the source network device can allocate resources to the relay network device for transmitting information related to the handover process. Consequently, in scenarios where a terminal device switches network devices (such as in a group handover scenario), the resources for information related to each terminal device transmitted by the relay network device can be dispersed, rather than being overly concentrated. This can balance the network load, reduce peak network load, and avoid network congestion. On the other hand, the network side can dynamically adjust the transmission path from the source network to the target network based on near-real-time path delay information, thereby better matching the service needs of different terminal types and improving communication quality and satisfaction.

[0184] Based on the contents shown in Figures 2A, 2B, 3A, 3B, 4 and 5 and the other contents mentioned above, Figure 6 exemplarily shows a possible flow chart of a communication method provided by an embodiment of the present application. The scheme provided in Figure 6 can be regarded as an extended embodiment of the scheme provided in Figure 4. The various execution entities involved in Figure 6 can refer to the relevant description in Figure 4 and will not be repeated here. In the scheme provided in Figure 6, when the terminal device is in a connected state, the network device can send measurement configuration information to the terminal device via an RRC connection reconfiguration message. The terminal device measures the signal strength of the serving cell and the neighboring cell according to the measurement configuration information sent by the network device, and reports the measurement results. Then, the network device can decide whether to switch based on the measurement results. This will be introduced below in conjunction with Figure 6.

[0185] Step 601: The source network device sends a first RRC reconfiguration (RRCReconfiguration) message to the terminal device.

[0186] The first RRC reconfiguration message may include measurement configuration information of at least one cell. The at least one cell may include a serving cell and a neighboring cell of the terminal device.

[0187] Measurement configuration information may include, for example, measurement frequency, SSB-based measurement timing configuration (SMTC) configuration, measurement reporting trigger conditions (e.g., periodic, aperiodic, event-triggered), measurement objects (e.g., location, signal quality), etc. SMTC configuration may include the duration, period, and time offset of the terminal device measurement.

[0188] Step 602: The terminal device sends a first RRC reconfiguration complete (RRCReconfigurationComplete) message to the source network device.

[0189] Among them, the first RRC reconfiguration completion message can be used to indicate that the terminal device has received the first RRC reconfiguration message.

[0190] Step 603: The terminal device performs measurement according to the measurement configuration information and sends a measurement report to the source network device.

[0191] Optionally, the terminal device may use the SSB associated with the currently activated BWP to perform measurements of the serving cell and / or neighboring cell based on the measurement configuration information. In some possible ways, the terminal device may periodically send measurement reports to the source network device. The period for sending the measurement report may be pre-set or may be obtained by the terminal device from the source network device. In other possible ways, the terminal device may send a measurement report to the source network device when the measurement result meets the reporting conditions. The reporting conditions may include at least one of the following: the signal quality of the serving cell is less than or equal to the first signal quality threshold, the signal quality of the neighboring cell is greater than or equal to the second signal quality threshold, etc.

[0192] The measurement report may include parameters used to reflect signal quality. In the present application, the parameters used to reflect signal quality may include, but are not limited to, at least one of the following: reference signal receiving power (RSRP), reference signal receiving quality (RSRQ), or received signal strength indication (RSSI).

[0193] In one possible implementation, the cell signal quality reported by the terminal device may be associated with the location information of the terminal device. The location information may include, for example, a global navigation satellite system (GNSS) location or a wave position identifier (ID). The source network device may determine whether the terminal device needs to switch network devices with the aid of the location information.

[0194] Step 604: The terminal device sends fourth information to the source network device.

[0195] Correspondingly, the source network device receives the fourth information.

[0196] The relevant contents of step 604 refer to the relevant description of the aforementioned step 401 and will not be repeated here.

[0197] Step 605: The source network device performs a handover decision based on the measurement report from the terminal device.

[0198] For example, if the measurement report of the terminal device includes the signal quality of the cell of the first target network device, and the signal quality of the cell of the first target network device is greater than or equal to the second signal quality threshold, and the position of the terminal device and the reference position of the source network are greater than the first distance threshold and the position of the terminal device and the reference position of the first target network are less than the second distance threshold, then the source network device can determine to switch the terminal device to the first target network device.

[0199] In step 606 , the source network device sends a handover request message.

[0200] Correspondingly, the relay network device receives the handover request message.

[0201] The switching request is used to request switching the terminal device from the source network device to the first target network device.

[0202] The switching request message may be an example of the aforementioned first information. The switching request message may include indication information of the first resource. For related content, please refer to the aforementioned description of the first information and will not be repeated here.

[0203] For step 606, please refer to the content of the aforementioned step 402 and will not be repeated here.

[0204] Step 607: The relay network device obtains indication information of the first resource from the handover request message.

[0205] For step 607, please refer to the content of the aforementioned step 403 and will not be repeated here.

[0206] Step 608: The relay network device sends a handover request message.

[0207] Correspondingly, the first target network device receives the handover request message.

[0208] For step 608, please refer to the content of the aforementioned step 404 and will not be repeated here.

[0209] Step 609: The first target network device performs admission control.

[0210] For example, the first target network device may configure the resources required for switching for the terminal device, such as at least one of the cell radio network temporary identifier (C-RNTI), preamble, random access channel occasion (RO) and time-frequency resources required for switching.

[0211] The first target network device may also obtain the first resource, and then receive the handover-related information from the relay network device on the first resource.

[0212] Step 610: The first target network device sends a first handover response message.

[0213] Correspondingly, the relay network device receives a first handover response message. The first handover response message may be, for example, a handover request acknowledgement. The first handover response message is a response message to the first message. The handover request response message may be used to indicate that the first target network device agrees to handover the terminal device to the first target network device.

[0214] The first switching response information may include transmission mode indication information, and the transmission mode indication information indicates the second transmission mode. It can also be understood that: the first switching response information includes information for indicating that the transmission mode of the relay network device is the second transmission mode, and the second transmission mode instructs the relay network device to relay and forward the first switching response information. It can also be understood that: the second transmission mode instructs the relay network device to only relay and forward the first switching response information without obtaining the content in the information. The relay network device may relay and forward the first switching response information transparently (forwarding in transparent working mode) or regenerative forwarding (forwarding in regenerative working mode).

[0215] In a possible implementation manner, the handover request response message may further include: at least one of the C-RNTI, preamble, RO, and time-frequency resources required for the handover.

[0216] Step 611: The relay network device sends a first switching response message.

[0217] Correspondingly, the source network device receives the first switching response information.

[0218] Step 612: The source network device sends a second RRC reconfiguration message to the terminal device.

[0219] The second RRC reconfiguration message may also be referred to as a handover command, which is used to instruct the terminal device to switch from the source network device to the first target network device.

[0220] Optionally, the second RRC reconfiguration message may include configuration parameters of the cell of the first target network device, such as an identifier of the cell of the first target network device, or a frequency of the cell of the first target network device. The second RRC reconfiguration message may also include, for example, at least one of a C-RNTI, a preamble, an RO, and time-frequency resources required for the handover.

[0221] Step 613: The source network device sends second information.

[0222] Correspondingly, the relay network device receives the second information.

[0223] In one possible implementation, the second information may also include transmission mode indication information, where the transmission mode indication information indicates a second transmission mode. This can also be understood as follows: the second information also includes information indicating that the relay network device's transmission mode is the second transmission mode, where the second transmission mode instructs the relay network device to relay and forward the second information. The relay network device does not need to obtain information from the second information.

[0224] The second information may include, for example, a sequence number (SN) status transfer message. The SN status transfer message may include a sequence number indicating a data packet that the source network device has transmitted to the terminal device. Optionally, the source network device forwards the data to be transmitted to the terminal device to the first target network device.

[0225] For another example, the second information includes: the context of the terminal device (UE context release).

[0226] For another example, the second information includes a handover response (HO Acknowledgement).

[0227] The content of step 613 refers to the relevant content of the aforementioned step 405 and will not be repeated here.

[0228] Step 614: The relay network device sends the second information via the first resource.

[0229] Correspondingly, the first target network device receives the second information.

[0230] The content of step 614 refers to the relevant content of the aforementioned step 406 and will not be repeated here.

[0231] In step 615 , the terminal device sends a random access message to the first target network device according to the configuration parameters of the cell of the first target network device in the second RRC reconfiguration message, requesting access to the cell of the first target network device.

[0232] The terminal device switches to the first target network device using a random access channel (RACH) or a RACH-less procedure. The random access preamble in the random access message is a dedicated preamble (e.g., a preamble allocated to the terminal by the first target network device), which is different from the contention-based random access preamble used during initial access. Furthermore, the period of the resource used to transmit the random access message may be at least one of the following: 10ms, 20ms, 40ms, 80ms, or 160ms.

[0233] In step 616, the first target network device sends a path switch request message to the AMF.

[0234] The path switching request message may be used to request the core network to send the data of the terminal device to the first target network device.

[0235] In step 617, the AMF sends a path switch request acknowledgement message to the first target network device.

[0236] After receiving the path switch request response message, the first target network device may send the uplink data from the terminal device to the core network.

[0237] In step 618 , the first target network device sends a random access response (RAR) message to the terminal device.

[0238] Step 619: The terminal device sends a second RRC reconfiguration completion message to the first target network device.

[0239] After accessing the first target network device, the terminal device can exchange data with the first target network device. For example, the terminal device can send uplink data to the first target network device. For another example, the terminal device can receive downlink data from the first target network device.

[0240] The core network transmission path changes, the first target network device can instruct the source network device to release the context information of the terminal device, and the first target network device can send new measurement configuration information to the terminal device, and the terminal device can also return a reconfiguration response.

[0241] Using the method shown in Figure 6, a terminal device can be switched from a source network device to a first target network device. During this process, the source network device allocates resources to the relay network device via a handover request message, and instructs the relay network device to transmit handover-related information using these resources. Because the resources used by the relay network device to transmit information related to each terminal device can be dispersed, rather than concentrated, network load can be balanced, reducing peak loads and improving communication quality.

[0242] The solution provided in the embodiment of the present application can be applicable to multi-hop transmission (i.e., at least one relay network device is included between the source network device and the first target network device), and can also be applicable to satellite-to-ground transmission scenarios (i.e., the transmission path between the source network and the target network contains at least one ground device, and the ground device can be a ground gateway, a ground-deployed network device, etc.). The embodiment of the present application does not limit the specific switching method of the terminal device. For example, the switching of the terminal device can be layer 3 (layer 3, L3) switching, bottom layer switching (such as layer 1 or layer 2-triggered mobility (layer 1 / layer 2-triggered mobility, LTM) switching), or conditional handover (CHO) switching, etc.

[0243] Based on the contents shown in Figures 2A, 2B, 3A, 3B, 4, 5 and 6 and the other contents mentioned above, Figure 7 exemplarily shows a possible flow chart of a communication method provided by an embodiment of the present application. The scheme provided in Figure 7 can be regarded as an extended embodiment of the scheme provided in Figures 4 and 6. The various execution entities involved in Figure 7 can refer to the relevant description in Figure 4 and will not be repeated here. In the scheme provided in Figure 7, the terminal device can be switched from the source network device to the first target network device, and the terminal device can also be switched from the source network device to the second target network device. The first target network device and the second target network device can be located in the same physical device or in two different physical devices. For example, the first network device carries a primary cell (Pcell), and the second network device carries a secondary cell (Scell) or a primary secondary cell (PScell). In the scheme provided in Figure 7, for different target network devices, the source network device can also allocate resources to different target network devices respectively, so that the network load can be further balanced.

[0244] To make it easier to understand the implementation scheme provided in Figure 7, Figure 8 exemplarily provides a schematic diagram of the architecture of a communication system. As shown in Figure 8, the communication system includes a source network device, a first target network device, a second target network device, and at least one relay network device. Relay network device #1 and relay network device #2 are included between the source network device and the first target network device. Relay network device #1 and relay network device #2 are included between the source network device and the second target network device. The first target network device can also be included between the source network device and the second target network device, and the first target network device can also be regarded as a relay network device. Relay network device #1 and relay network device #2 can be satellite devices or ground-deployed network devices. Figure 8 uses satellite devices as an example for illustration. The following is an introduction in conjunction with Figures 7 and 8.

[0245] Step 701: The source network device sends a first RRC reconfiguration message to the terminal device.

[0246] The content of step 701 refers to the aforementioned step 601 and will not be repeated here.

[0247] Step 702: The terminal device sends a first RRC reconfiguration completion message to the source network device.

[0248] The content of step 702 refers to the aforementioned step 602 and will not be repeated here.

[0249] Step 703: The terminal device performs measurement according to the measurement configuration information and sends a measurement report to the source network device.

[0250] The content of step 703 refers to the aforementioned step 603 and will not be repeated here.

[0251] Step 704: The terminal device sends fourth information to the source network device.

[0252] Correspondingly, the source network device receives the fourth information.

[0253] The content of step 704 refers to the aforementioned step 604 and will not be repeated here.

[0254] Step 705: The source network device performs a handover decision based on the measurement report from the terminal device.

[0255] The content of step 705 refers to the aforementioned step 605 and will not be repeated here.

[0256] In step 706 , the source network device sends a handover request message.

[0257] Correspondingly, the relay network device receives the handover request message.

[0258] The switching request is used to request that the terminal device be switched from the source network device to the first target network device. The switching request is also used to request that the terminal device be switched from the source network device to the second target network device.

[0259] The handover request message may be an example of the aforementioned first information, and the handover request message may include information indicating the first resource. In the embodiment shown in FIG7 , the first information (e.g., the handover request message) also includes information indicating the second resource. The first resource is used by the relay network device to transmit information related to the handover process to the first target network device. The second resource is used by the relay network device to transmit information related to the handover process to the second target network device.

[0260] The switching request message carries transmission mode indication information, and the transmission mode indication information indicates the first transmission mode. The relay network device needs to obtain not only the indication information of the first resource, but also the indication information of the second resource. For example, the indication information of the second resource is also carried in the aforementioned first field, and the relay network device identifies the information of the first field. The first field can be a field that the relay network device needs to identify as defined by the protocol, or a field that the relay network device needs to identify as negotiated, or the first information carries information for indicating that the relay network device needs to identify the content of the first field. The indication information of the second resource is similar to the indication information of the first resource. For example, the indication information of the second resource includes the time period [t3, t4] and the reserved bandwidth resource #2. For related content, please refer to the indication information of the first resource and will not be repeated here.

[0261] Similarly, when there are multiple relay network devices between the source network device and the second target network device, the first information can also carry indication information of multiple second resources, and one relay network device can correspond to one second resource. For related content, please refer to the description of multiple first resources and will not be repeated here.

[0262] The first information also includes at least one of the following: information indicating the second destination network device; information indicating the information transmission path from the source network device to the second destination network device; information indicating a relay network device in the information transmission path from the source network device to the second destination network device; and information indicating the latency of the information transmission path from the source network device to the second destination network device. The relevant information is similar to the information related to the first destination network device and is not further described.

[0263] For other relevant contents of the switching request message, please refer to the aforementioned description of the first information and will not be repeated here.

[0264] For step 706, please refer to the content of the aforementioned step 606 and will not be repeated here.

[0265] Step 707: The relay network device obtains indication information of the first resource and indication information of the second resource from the handover request message.

[0266] The relay network device in step 707 may be relay network device #1 or relay network device #2 in Figure 8. In one possible implementation, the first target network device may also be considered a relay network device between the source network device and the second target network device. In this case, the relay network device in step 707 may also be the first target network device.

[0267] For step 707, please refer to the content of the aforementioned step 607 and will not be repeated here.

[0268] Step 708: The relay network device sends a handover request message.

[0269] Correspondingly, the first target network device receives the handover request message.

[0270] In step 708 , the second target network device may also receive the handover request message.

[0271] In the embodiment of the present application, the first target network device and the second network device may receive the handover request message from different relay network devices, or receive the handover request message from the same relay network device. In one possible implementation, the second target network device may also receive the handover request message from the first target network device.

[0272] For step 708, please refer to the content of the aforementioned step 608 and will not be repeated here.

[0273] Step 709: The first target network device performs admission control.

[0274] For step 709, please refer to the content of the aforementioned step 609 and will not be repeated here.

[0275] Step 710: The second target network device performs admission control.

[0276] For example, the second target network device may configure resources required for handover for the terminal device, such as at least one of the C-RNTI, preamble, RO, and time-frequency resources required for handover.

[0277] The second target network device may also obtain the second resource, and then receive the handover-related information from the relay network device on the second resource.

[0278] The content of the admission control performed by the second target network device is similar to that performed by the first target network device. For step 710 , reference may be made to the content of the aforementioned step 609 and will not be repeated herein.

[0279] Step 711: The first target network device sends a first handover response message.

[0280] Correspondingly, the relay network device receives the first switching response information.

[0281] For step 711 , please refer to the content of the aforementioned step 610 and will not be described in detail.

[0282] Step 712: The relay network device sends a first switching response message.

[0283] Correspondingly, the source network device receives the first switching response information.

[0284] For step 712, please refer to the content of the aforementioned step 611 and no further details will be given.

[0285] Step 713: The second target network device sends a second handover response message.

[0286] Correspondingly, the relay network device receives the second switching response information.

[0287] The content of the second handover response information is similar to that of the first handover response information. For step 713 , reference may be made to the content of the aforementioned step 610 , which will not be described in detail.

[0288] Step 714: The relay network device sends a second switching response message.

[0289] Correspondingly, the source network device receives the second switching response information.

[0290] For step 714, please refer to the content of the aforementioned step 611 and will not be repeated here.

[0291] Step 715: The source network device sends a second RRC reconfiguration message to the terminal device.

[0292] For step 715, please refer to the content of the aforementioned step 612 and will not be repeated here.

[0293] Step 716: The source network device sends a third RRC reconfiguration message to the terminal device.

[0294] The third RRC reconfiguration message may also be referred to as a handover command, which is used to instruct the terminal device to switch from the source network device to the second target network device.

[0295] Optionally, the third RRC reconfiguration message may include configuration parameters of the cell of the second target network device. The content of the third RRC reconfiguration message is similar to that of the second RRC reconfiguration message and will not be described in detail.

[0296] For step 716, please refer to the content of the aforementioned step 612 and will not be repeated here.

[0297] Step 717: The source network device sends second information.

[0298] Correspondingly, the relay network device receives the second information.

[0299] The content of step 717 refers to the relevant content of the aforementioned step 613 and will not be repeated here.

[0300] Step 718: The relay network device sends the second information via the first resource.

[0301] Correspondingly, the first target network device receives the second information.

[0302] The content of step 718 refers to the relevant content of the aforementioned step 614 and will not be repeated here.

[0303] Step 719: The source network device sends third information.

[0304] Correspondingly, the relay network device receives the third information.

[0305] The third information is information related to the handover process, such as handover signaling, UE context information, user data forwarding, or SN status transfer information.

[0306] In one possible implementation, the third information may also include transmission mode indication information, where the transmission mode indication information indicates the second transmission mode. This can also be understood as follows: the third information also includes information indicating that the relay network device's transmission mode is the second transmission mode, where the second transmission mode instructs the relay network device to relay and forward the third information. The relay network device does not need to obtain information from the third information.

[0307] The content of step 719 is similar to the relevant content of the aforementioned step 613 and will not be repeated here.

[0308] Step 720: The relay network device sends third information via the second resource.

[0309] Correspondingly, the second target network device receives the third information.

[0310] The content of step 720 is similar to the relevant content of the aforementioned step 614 and will not be repeated here.

[0311] Step 721: The terminal device accesses the first target network device according to the second RRC reconfiguration message.

[0312] The content of step 721 can refer to the implementation method given in any of the aforementioned steps 615, 616, 617, 618, and 619, and will not be repeated here.

[0313] Step 722: The terminal device accesses the second target network device according to the third RRC reconfiguration message.

[0314] The content of step 722 can refer to the implementation method given in any of the aforementioned steps 615, 616, 617, 618, and 619, and will not be repeated here.

[0315] Using the method shown in Figure 7, a terminal device can be switched from a source network device to a first target network device and a second target network device. During this process, the source network device allocates resources to the relay network device via a handover request message, and allocates resources to different target network devices separately. The relay network device then transmits handover-related information to the different target network devices using these different resources. Because the resources for the information associated with each terminal device transmitted by the relay network device to different target network devices can be dispersed, they do not need to be overly concentrated. This can balance the network load, reduce peak network load, and thus improve communication quality.

[0316] In the embodiment provided in FIG7 , the relay network device is a relay network device on the information transmission path between the source network device and the first target network device, and is also a relay network device on the information transmission path between the source network device and the second target network device. In actual applications, the relay network devices on the two information transmission paths between the source network device and the two target network devices are not all identical. For example, there may be a relay network device on the information transmission path between the source network device and the first target network device, but not on the information transmission path between the source network device and the second target network device. In this case, relay network device #1 can obtain only information about the first resource from the first information, or obtain both information about the first resource and information about the second resource from the first information. Relay network device #1 may also subsequently transmit only information between the source network device and the first target network device, such as the first handover response information, without transmitting the second handover response information. The second handover response information is transmitted by the relay network device between the source network device and the second target network device.

[0317] In one possible implementation, when the time domain resource in the second resource expires, the relay network device may release the second resource. For example, the time domain resource in the second resource includes the time period [t3, t4]. The relay network device may release the second resource after time (t4 + t_offset'), where t_offset' is greater than or equal to 0. t_offset' and t_offset may be the same or different.

[0318] Based on the contents shown in Figures 2A, 2B, 3A, 3B, 4, 5, 6, 7 and 8 and the other contents mentioned above, Figure 9 exemplarily shows a possible flow chart of a communication method provided in an embodiment of the present application. The scheme provided in Figure 9 can be regarded as an extended embodiment of the scheme provided in Figures 4, 6 and 7. The various execution entities involved in Figure 9 can refer to the relevant description in Figure 4 and will not be repeated here. In the scheme provided in Figure 9, each relay network device can also store the context information of the terminal device. After the terminal device fails to switch, the terminal device can select the relay network device that stores the context information of the terminal device, and reconstruct the information transmission path between the source network device and the first target network device based on these relay network devices. In this scheme, since the terminal device can select the relay network device that stores the context information of the terminal device to reconstruct the information transmission path, the speed of establishing the information transmission path can be improved.

[0319] To make it easier to understand the implementation scheme provided in FIG9 , FIG10 exemplarily provides a schematic diagram of the architecture of a communication system. As shown in FIG10 , the communication system includes a source network device, a first target network device, and at least one relay network device (such as relay network device #1, relay network device #2, relay network device #3, and relay network device #4 shown in the figure). Relay network device #2 and relay network device #4 are relay network devices that store context information of terminal devices. The relay network device can be a satellite device or a ground-deployed network device. FIG10 uses a satellite device as an example for illustration. The following is an introduction in conjunction with FIG9 and FIG10 .

[0320] Step 901: The source network device sends a first RRC reconfiguration message to the terminal device.

[0321] The content of step 901 refers to the aforementioned step 601 and will not be repeated here.

[0322] Step 902: The terminal device sends a first RRC reconfiguration completion message to the source network device.

[0323] The content of step 902 refers to the aforementioned step 602 and will not be repeated here.

[0324] Step 903: The terminal device performs measurement according to the measurement configuration information and sends a measurement report to the source network device.

[0325] The content of step 903 refers to the aforementioned step 603 and will not be repeated here.

[0326] Step 904: The terminal device sends fourth information to the source network device.

[0327] Correspondingly, the source network device receives the fourth information.

[0328] The content of step 904 refers to the aforementioned step 604 and will not be repeated here.

[0329] Step 905: The source network device performs a handover decision based on the measurement report from the terminal device.

[0330] The content of step 905 refers to the aforementioned step 605 and will not be repeated here.

[0331] In step 906 , the source network device sends a handover request message.

[0332] Correspondingly, the relay network device receives the handover request message.

[0333] The handover request is used to request handover of the terminal device from the source network device to the first target network device. The handover request message may be an example of the aforementioned first information, and the handover request message may include indication information of the first resource.

[0334] In the embodiment shown in FIG. 9 , the first information (eg, a handover request message) may further include context information of the terminal device.

[0335] The handover request message carries transmission mode indication information, where the transmission mode indication information indicates the first transmission mode. The relay network device not only needs to obtain the indication information of the first resource, but also needs to obtain the context information of the terminal device. For example, the context information of the terminal device is also carried in the aforementioned first field, and the relay network device identifies the information in the first field. The first field can be a field defined by the protocol that the relay network device needs to identify, or a field that the relay network device needs to identify through negotiation, or the first message carries information for indicating that the relay network device needs to identify the content of the first field.

[0336] In another possible implementation, the first information also includes identification information of the relay network device for which the context information of the terminal device needs to be identified. That is, not all relay network devices need to identify the context information of the terminal device in the first information, but rather some relay network devices do. The identification information of these relay network devices can be included in the first information, and the relay network device can determine whether it needs to identify the context information of the terminal device in the first information based on this information.

[0337] For other relevant contents of the switching request message, please refer to the aforementioned description of the first information and will not be repeated here.

[0338] For step 906, please refer to the content of the aforementioned step 606 and will not be repeated here.

[0339] Step 907: The relay network device obtains indication information of the first resource from the handover request message.

[0340] For step 907, please refer to the content of the aforementioned step 607 and will not be repeated here.

[0341] Step 908: The relay network device sends a handover request message.

[0342] Correspondingly, the first target network device receives the handover request message.

[0343] For step 908, please refer to the content of the aforementioned step 608 and will not be repeated here.

[0344] Step 909: The first target network device performs admission control.

[0345] For step 909, please refer to the content of the aforementioned step 609 and will not be repeated here.

[0346] Step 910: The first target network device sends a first handover response message.

[0347] Correspondingly, the relay network device receives the first switching response information.

[0348] For step 910, please refer to the content of the aforementioned step 610 and will not be repeated here.

[0349] Step 911: The relay network device sends a first switching response message.

[0350] Correspondingly, the source network device receives the first switching response information.

[0351] For step 911, please refer to the content of the aforementioned step 611 and will not be repeated here.

[0352] Step 912: The source network device sends a second RRC reconfiguration message to the terminal device.

[0353] For step 912, please refer to the content of the aforementioned step 612 and will not be repeated here.

[0354] Step 913: The source network device sends second information.

[0355] Correspondingly, the relay network device receives the second information.

[0356] The content of step 913 refers to the relevant content of the aforementioned step 613 and will not be repeated here.

[0357] Step 914: The relay network device sends the second information via the first resource.

[0358] Correspondingly, the first target network device receives the second information.

[0359] The content of step 914 refers to the relevant content of the aforementioned step 614 and will not be repeated here.

[0360] Step 915: The terminal device accesses the first target network device according to the second RRC reconfiguration message.

[0361] The content of step 915 can refer to the implementation method given in any of the aforementioned steps 615, 616, 617, 618, and 619, and will not be repeated here.

[0362] Step 916: The source network device sends fifth information to the terminal device.

[0363] Correspondingly, the terminal device receives fifth information, where the fifth information indicates the relay network device storing the context information of the terminal device. For example, the fifth information may include identification information of the relay network device storing the context information of the terminal device.

[0364] Step 917 : When the terminal device determines that a communication failure occurs in the information transmission path between the terminal device and the first target network device, the terminal device re-establishes a communication link between the terminal device and at least one relay network device based on the fifth information.

[0365] For example, in step 917 , when the terminal device determines that the information transmission path between the terminal device and the first target network device fails, the terminal device reestablishes the information transmission path between the terminal device and the first target network device based on the fifth information.

[0366] Through the method shown in Figure 9, the terminal device can select relay network devices that store the context information of the terminal device and try to use these relay network devices to re-establish the link. Since these relay network devices have stored the context information of the terminal device in advance, the new link can be rebuilt more quickly, thereby shortening the time of communication failure.

[0367] Based on the contents shown in Figures 2A, 2B, 3A, 3B, 4, 5, 6, 7, 8, 9 and 10 and the other contents mentioned above, Figure 11 exemplarily shows a possible flow chart of a communication method provided in an embodiment of the present application. The scheme provided in Figure 11 can be regarded as an extended embodiment of the scheme provided in Figures 4, 6, 7 and 9. The various execution entities involved in Figure 11 can refer to the relevant description in Figure 4 and will not be repeated here. In the scheme provided in Figure 11, when the relay network device finds that the original path has a communication failure, the relay network device can determine a new path and transmit information to the first target network device based on the new path. In this scheme, since the relay network device can determine the path, the scheme can improve the efficiency of information transmission between the source network device and the first target network device.

[0368] In order to make it easier to understand the implementation scheme provided in Figure 11, Figure 12 exemplarily provides an architectural diagram of a communication system. As shown in Figure 12, the communication system includes a source network device, a first target network device and at least one relay network device. As shown in Figure 12, the communication system also includes a first path and a second path. In the event of communication failure on the first path, the relay network device (such as relay network device #1) selects the second path to communicate with the first target network device. The first path includes: source network device-relay network device #1-relay network device #2-first target network device. The second path includes: source network device-relay network device #1-relay network device #3-relay network device #4-first target network device. The relay network device can be a satellite device or a ground-deployed network device. Figure 12 uses a satellite device as an example for illustration.

[0369] The following is an introduction with reference to FIG11 and FIG12.

[0370] Step 1101: The source network device sends a first RRC reconfiguration message to the terminal device.

[0371] The content of step 1101 refers to the aforementioned step 601 and will not be repeated here.

[0372] Step 1102: The terminal device sends a first RRC reconfiguration completion message to the source network device.

[0373] The content of step 1102 refers to the aforementioned step 602 and will not be repeated here.

[0374] Step 1103: The terminal device performs measurement according to the measurement configuration information and sends a measurement report to the source network device.

[0375] The content of step 1103 refers to the aforementioned step 603 and will not be repeated here.

[0376] Step 1104: The terminal device sends fourth information to the source network device.

[0377] Correspondingly, the source network device receives the fourth information.

[0378] The content of step 1104 refers to the aforementioned step 604 and will not be repeated here.

[0379] Step 1105: The source network device performs a handover decision based on the measurement report from the terminal device.

[0380] The content of step 1105 refers to the aforementioned step 605 and will not be repeated here.

[0381] In step 1106 , the source network device sends a handover request message.

[0382] Correspondingly, the relay network device receives the handover request message.

[0383] The handover request is used to request handover of the terminal device from the source network device to the first target network device. The handover request message may be an example of the aforementioned first information, and the handover request message may include indication information of the first resource.

[0384] For other relevant contents of the switching request message, please refer to the aforementioned description of the first information and will not be repeated here.

[0385] For step 1106, please refer to the content of the aforementioned step 606 and will not be repeated here.

[0386] Step 1107: The relay network device obtains indication information of the first resource from the handover request message.

[0387] For step 1107, please refer to the content of the aforementioned step 607 and will not be repeated here.

[0388] Step 1108: The relay network device sends a handover request message.

[0389] Correspondingly, the first target network device receives the handover request message.

[0390] In step 1108, the handover request message may also include information indicating a path. For example, in the embodiment shown in FIG8 , the handover request message sent by the source network device also includes information indicating the first path. The relay network device is relay network device #1 in FIG8 . If relay network device #1 detects a communication failure along the first path, the relay network device may determine a second path based on the topology information and send a handover request message to the first target network device based on the second path, i.e., to relay network device #3.

[0391] In another possible implementation, the switching request message sent by relay network device #3 may include information indicating the second path, such as identification information of relay network device #4.

[0392] For step 1108, please refer to the content of the aforementioned step 608 and will not be repeated here.

[0393] Step 1109: The first target network device performs admission control.

[0394] For step 1109, please refer to the content of the aforementioned step 609 and will not be repeated here.

[0395] Step 1110: The first target network device sends a first handover response message.

[0396] Correspondingly, the relay network device receives the first switching response information.

[0397] In step 1110, the first target network device may send first handover response information based on the second path. For example, the first handover response information may include information indicating the second path, such as identification information of relay network device #4.

[0398] For step 1110, please refer to the content of the aforementioned step 610 and will not be repeated here.

[0399] Step 1111: The relay network device sends first switching response information.

[0400] Correspondingly, the source network device receives the first switching response information.

[0401] For step 1111, please refer to the content of the aforementioned step 611 and will not be repeated here.

[0402] Step 1112: The source network device sends a second RRC reconfiguration message to the terminal device.

[0403] For step 1112, please refer to the content of the aforementioned step 612 and will not be repeated here.

[0404] Step 1113: The source network device sends second information.

[0405] Correspondingly, the relay network device receives the second information.

[0406] In step 1113, the source network device may send the second information via the second path. The second information may include information indicating the second path, such as identification information of relay network device #1 or identification information of the second path.

[0407] The content of step 1113 refers to the relevant content of the aforementioned step 613 and will not be repeated here.

[0408] Step 1114: The relay network device sends the second information via the first resource.

[0409] Correspondingly, the first target network device receives the second information.

[0410] In step 1114, for example, in the embodiment shown in FIG8 , the second information sent by the source network device also includes information indicating path #2. Relay network device #1 sends the second information to the first target network device based on the second path, that is, to relay network device #3.

[0411] In another possible implementation, the second information sent by relay network device #3 may include information indicating the second path, such as identification information of relay network device #4.

[0412] The content of step 1114 refers to the relevant content of the aforementioned step 614 and will not be repeated here.

[0413] Step 1115: The terminal device accesses the first target network device according to the second RRC reconfiguration message.

[0414] The content of step 1115 can refer to the implementation method given in any of the aforementioned steps 615, 616, 617, 618, and 619, and will not be repeated here.

[0415] In the example provided in Figure 11, the relay network device detects a communication failure along a path during transmission of the first information and switches the path. In actual applications, the relay network device may also detect a communication failure along a path during transmission of the second information and subsequently switch the path. For example, the first information is transmitted along a first path, but when transmitting the second information, the relay network device detects a communication failure along the first path and then switches the second information along the second path. Related scenarios are similar and will not be further described.

[0416] In the solution provided in FIG. 11 , since the relay network device also has the function of switching paths, this solution can speed up path switching and shorten the duration of communication failure.

[0417] It is understood that in order to implement the functions in the above embodiments, the terminal device, the source network device, the relay network device, and the first target network device may include hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should readily appreciate that, in combination with the units and method steps of the various examples described in the embodiments disclosed in this application, this application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in hardware or in a manner driven by computer software depends on the specific application scenario and design constraints of the technical solution.

[0418] Figures 13 and 14 are schematic diagrams of the structures of possible communication devices provided by embodiments of the present application. These communication devices can be used to implement the functions of the terminal device, source network device, first target network device or relay network device in the above method embodiments, and thus can also achieve the beneficial effects possessed by the above method embodiments. In an embodiment of the present application, the communication device can be a terminal device as shown in Figure 2A, Figure 2B, Figure 3A or Figure 3B, or a network device (such as a RAN node) as shown in Figure 1, or a satellite device as shown in Figure 1, or a chip system applied to the terminal device, satellite device or network device shown in Figure 2A, Figure 2B, Figure 3A or Figure 3B.

[0419] As shown in Figure 13, communication device 1300 includes a processing unit 1310 and a transceiver unit 1320. Communication device 1300 is used to implement the functions of a terminal device, a source network device, a relay network device, or a first target network device in the method embodiments shown in Figures 4, 6, 7, 9, or 11. Transceiver unit 1320 may also be referred to as a communication unit. Transceiver unit 1320 may include a transmitting unit and a receiving unit.

[0420] When the communication device 1300 is used to implement the function of the source network device in the method embodiment shown in Figure 4, Figure 6, Figure 7, Figure 9 or Figure 11, the transceiver unit 1320 is used to send first information to the first target network device and send second information to the first target network device, where the second information is information related to the handover process.

[0421] When the communication device 1300 is used to implement the function of the source network device in the method embodiments shown in Figures 4, 6, 7, 9 or 11, in one possible implementation, the transceiver unit 1320 is used to receive first switching response information from the first target network device.

[0422] When the communication device 1300 is used to implement the function of the source network device in the method embodiments shown in Figures 4, 6, 7, 9 or 11, in one possible implementation, the transceiver unit 1320 is used to send the third information to the second target network device.

[0423] When the communication device 1300 is used to implement the functions of the terminal device in the method embodiments shown in Figures 4, 6, 7, 9 or 11, in one possible implementation, the processing unit 1310 is used to obtain the fourth information, and the transceiver unit 1320 is used to send the fourth information to the source network device.

[0424] When the communication device 1300 is used to implement the function of the terminal device in the method embodiment shown in Figures 4, 6, 7, 9 or 11, in one possible implementation, the transceiver unit 1320 is used to receive the fifth information, and the processing unit 1310 is used to determine the information transmission path between the terminal device and at least one relay network device based on the fifth information.

[0425] When communication device 1300 is used to implement the functions of a relay network device in the method embodiments shown in Figures 4, 6, 7, 9, or 11, in one possible implementation, transceiver unit 1320 is configured to receive first information from a source network device. Processing unit 1310 is configured to obtain indication information of a first resource from the first information. Transceiver unit 1320 is configured to send the first information to a first target network device, receive second information from the source network device, and send the second information to the first target network device via the first resource.

[0426] When the communication device 1300 is used to implement the function of the relay network device in the method embodiments shown in Figures 4, 6, 7, 9 or 11, in one possible implementation, the transceiver unit 1320 is used to receive the first switching response information from the first target network device and send the first switching response information to the source network device.

[0427] When the communication device 1300 is used to implement the functions of the relay network device in the method embodiments shown in Figures 4, 6, 7, 9, or 11, in one possible implementation, the processing unit 1310 is configured to obtain indication information of the second resource from the first information. The transceiver unit 1320 is configured to receive third information from the source network device and send the third information to the second target network device via the second resource, where the third information is information related to the handover process.

[0428] When the communication device 1300 is used to implement the function of the relay network device in the method embodiment shown in Figures 4, 6, 7, 9 or 11, in one possible implementation, the transceiver unit 1320 is used to receive the second switching response information from the second target network device and send the second switching response information to the source network device.

[0429] When the communication device 1300 is used to implement the function of the relay network device in the method embodiment shown in Figure 4, Figure 6, Figure 7, Figure 9 or Figure 11, in one possible implementation, the processing unit 1310 is used to obtain context information of the terminal device from the first information.

[0430] When the communication device 1300 is used to implement the function of the relay network device in the method embodiments shown in Figures 4, 6, 7, 9 or 11, in one possible implementation, the processing unit 1310 is used to determine a second path when it is determined that the first path cannot be used to send the first information, and the transceiver unit 1320 is used to send the first information to the first target network device based on the second path.

[0431] When the communication device 1300 is used to implement the function of the first target network device in the method embodiment shown in Figures 4, 6, 7, 9 or 11, in one possible implementation, the transceiver unit 1320 is used to receive a first message from the source network device and receive a second message from the source network device, where the second information is information associated with the switching process.

[0432] When the communication device 1300 is used to implement the function of the first target network device in the method embodiment shown in Figure 4, Figure 6, Figure 7, Figure 9 or Figure 11, in one possible implementation, the transceiver unit 1320 is used to send first switching response information to the source network device.

[0433] For a more detailed description of the processing unit 1310 and the transceiver unit 1320 , please refer to the relevant description in the method embodiments shown in FIG. 4 , FIG. 6 , FIG. 7 , FIG. 9 or FIG. 11 .

[0434] As shown in Figure 14, communication device 1400 includes a processor 1410 and an interface circuit 1420. Processor 1410 and interface circuit 1420 are coupled to each other. It is understood that interface circuit 1420 can be a transceiver or an input / output interface. The input / output interface is used to input and / or output information, where output can be understood as sending and input can be understood as receiving. Optionally, communication device 1400 may also include a memory 1430 for storing instructions executed by processor 1410, or storing input data required by processor 1410 to execute instructions, or storing data generated after processor 1410 executes instructions.

[0435] When the communication device 1400 is used to implement the method shown in Figure 4, Figure 6, Figure 7, Figure 9 or Figure 11, the processor 1410 is used to implement the functions of the above-mentioned processing unit 1310, and the interface circuit 1420 is used to implement the functions of the above-mentioned transceiver unit 1320.

[0436] Based on the same concept, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program or instruction. When the computer program or instruction is executed by a communication device, the method in any embodiment of Figure 4, Figure 6, Figure 7, Figure 9 or Figure 11 can be implemented.

[0437] Based on the same concept, an embodiment of the present application provides a computer program product, which stores a computer program, wherein the computer program includes program instructions, which, when executed by a computer, can implement the method in any of the embodiments of Figures 4, 6, 7, 9 or 11.

[0438] When the above-mentioned communication device is a chip applied to a terminal, the terminal chip implements the functions of the terminal device in the above-mentioned method embodiment. When the terminal chip receives information from the base station, it can be understood that the information is first received by other modules in the terminal (such as a radio frequency module or antenna) and then sent to the terminal chip by these modules. When the terminal chip sends information to the base station, it can be understood that the information is first sent to other modules in the terminal (such as a radio frequency module or antenna) and then sent to the base station by these modules.

[0439] When the above-mentioned communication device is a chip applied to a base station, the base station chip implements the functions of the network device in the above-mentioned method embodiment. When the base station chip receives information from the terminal, it can be understood that the information is first received by other modules in the base station (such as a radio frequency module or antenna) and then sent to the base station chip by these modules. When the base station chip sends information to the terminal, it can be understood that the information is sent to other modules in the base station (such as a radio frequency module or antenna) and then sent to the terminal by these modules.

[0440] In this application, when entity A sends information to entity B, it can be done directly from A to B or indirectly through another entity. Similarly, when entity B receives information from entity A, it can be done directly from entity B or indirectly through another entity. Entities A and B herein can be RAN nodes or terminals, or modules within a RAN node or terminal. The sending and receiving of information can be information exchange between a RAN node and a terminal, for example, between a base station and a terminal; the sending and receiving of information can also be information exchange between two RAN nodes, for example, between a CU and a DU; the sending and receiving of information can also be information exchange between different modules within a device, for example, between a terminal chip and other modules in the terminal, or between a base station chip and other modules within the base station.

[0441] It is understood that the processor in the embodiments of the present application may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0442] The method steps in the embodiments of the present application can be implemented in hardware or in software instructions that can be executed by a processor. The software instructions can be composed of corresponding software modules, and the software modules can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disks, mobile hard disks, compact disc read-only memory (CD-ROM) or any other form of storage medium well known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. The storage medium can also be an integral part of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a base station or a terminal. The processor and the storage medium can also be present in a base station or a terminal as discrete components.

[0443] In the above embodiments, all or part of the embodiments may be implemented using software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments may be implemented in the form of a computer program product. A computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, all or part of the processes or functions of the embodiments of the present application are performed. The computer may be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user device, or other programmable device. The computer program or instructions may be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions may be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or data center that integrates one or more available media. The available media may be magnetic media, such as floppy disks, hard disks, or magnetic tapes; optical media, such as digital video disks; or semiconductor media, such as solid-state drives. The computer-readable storage medium may be a volatile or nonvolatile storage medium, or may include both volatile and nonvolatile types of storage media.

[0444] In the various embodiments of the present application, unless otherwise specified or there is a logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0445] In this application, "at least one" means one or more, and "more" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. In the text description of this application, the character " / " generally indicates that the previous and next associated objects are in an "or" relationship; in the formula of this application, the character " / " indicates that the previous and next associated objects are in a "division" relationship. "Including at least one of A, B and C" can mean: including A; including B; including C; including A and B; including A and C; including B and C; including A, B and C.

[0446] It is understood that the various numbers involved in the embodiments of this application (such as the numerical numbers "first" and "second", and the letter numbers "Implementation A1", "Implementation B1", "Implementation C1", etc.) are only for the convenience of description and are not intended to limit the scope of the embodiments of this application. The order of the sequence numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic.

Claims

1. A communication method, characterized in that: The method is applicable to a source network device, and the method comprises: Sending first information to a first target network device, the first information being used to request that a terminal device be switched from the source network device to the first target network device, the first information comprising indication information of a first resource, the information transmission path from the source network device to the first target network device comprising at least one relay network device, the first resource being used for a relay network device in the at least one relay network device to transmit information associated with a switching process; Sending second information to the first target network device, where the second information belongs to information associated with the switching process.

2. The method according to claim 1, characterized in that The indication information of the first resource includes at least one of the following: Information indicating a time period; Information indicating bandwidth resources; Information indicating the transmission rate; Information used to indicate quality of service requirements; Information indicating the quality of service experience; Information indicating the location of a relay network device; Information indicating polarization; or Used to indicate the information carried.

3. The method according to any one of claims 1 to 2, characterized in that: The first resource is used to transmit information associated with a handover process of a first type of terminal device; The first type of terminal device is associated with at least one of: a priority of the terminal device, a capability of the terminal device, a quality of service requirement of the terminal device, and a quality of service experience of the terminal device.

4. The method according to any one of claims 1 to 3, characterized in that: The information transmission path from the source network device to the first target network device includes multiple relay network devices, the first information includes indication information of multiple first resources, the multiple relay network devices are associated with one first resource among the multiple first resources, and two first resources associated with two relay network devices among the multiple relay network devices partially overlap or do not overlap.

5. The method according to any one of claims 1 to 4, characterized in that: The first information also includes: identification information of a relay network device associated with a first resource among the multiple first resources, identification information of the first target network device, path information from the source network device to the first target network device, and delay information from the source network device to the first target network device.

6. The method according to any one of claims 1 to 5, characterized in that: The first information includes: information for indicating that the transmission mode of the first information by the relay network device is a first transmission mode; The first transmission mode includes: a relay network device relays and forwards the first information, and obtains indication information of the first resource in the first information.

7. The method according to any one of claims 1 to 6, characterized in that: The method further comprises: Receive first switching response information from the first target network device, where the first switching response information is response information of the first information, and the first switching response information includes information for indicating that a transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the first switching response information.

8. The method according to any one of claims 1 to 7, characterized in that: The second information further includes: information for indicating that the transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the second information.

9. The method according to any one of claims 1 to 8, characterized in that The second information includes: a switching response, a sequence number SN status transmission, and at least one of the context of the terminal device.

10. The method according to any one of claims 1 to 9, characterized in that: The first information is also used to request that the terminal device be switched from the source network device to a second target network device. The first information also includes indication information of a second resource, and the second resource is used for the relay network device in the at least one relay network device to transmit information associated with the switching process to the second target network device.

11. The method according to claim 10, characterized in that The method further comprises: Sending third information to the second target network device, where the third information is information associated with the switching process.

12. The method according to claim 10 or 11, characterized in that The first information also includes: information for indicating the second target network device; information for indicating the information transmission path from the source network device to the second target network device; and information for indicating the relay network device in the information transmission path from the source network device to the second target network device.

13. The method according to any one of claims 10 to 12, characterized in that: The method further comprises: Receive second switching response information from the second target network device, where the second switching response information is response information to the first information, and the second switching response information includes information for indicating that the transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the second switching response information.

14. The method according to any one of claims 1 to 13, characterized in that: The first information also includes: context information of the terminal device; The first information further includes information for indicating that a relay network device in the at least one relay network device needs to obtain context information of the terminal device from the first information.

15. The method according to any one of claims 1 to 14, characterized in that: The first resource is associated with at least one of the following: mobile interruption time information of the terminal device; uplink service arrival rate of the terminal device; downlink service arrival rate of the terminal device; or the type of the terminal device.

16. A communication method, characterized in that: The method is applicable to a relay network device, wherein the relay network device belongs to at least one relay network device included in an information transmission path from a source network device to a first target network device, and the method comprises: receiving first information from the source network device, the first information being used to request switching of the terminal device from the source network device to the first target network device, the first information comprising indication information of a first resource, the first resource being used by the relay network device to transmit information associated with the switching process; Acquire indication information of the first resource from the first information; Sending the first information to a first target network device; receiving second information from the source network device, wherein the second information belongs to information associated with the switching process; The second information is sent to the first target network device at the first resource.

17. The method according to claim 16, characterized in that The indication information of the first resource includes at least one of the following: Information indicating a time period; Information indicating bandwidth resources; Information indicating the transmission rate; Information used to indicate quality of service requirements; Information indicating the quality of service experience; Information indicating location; Information indicating polarization mode; Used to indicate the information carried.

18. The method according to any one of claims 16 to 17, characterized in that: The first resource is used by the relay network device to transmit information associated with a switching process of a first type of terminal device; The first type of terminal device is associated with at least one of: a priority of the terminal device, a capability of the terminal device, a quality of service requirement of the terminal device, and a quality of service experience of the terminal device.

19. The method according to any one of claims 16 to 18, characterized in that: The information transmission path from the source network device to the first target network device includes multiple relay network devices, the first information includes indication information of multiple first resources, the multiple relay network devices are associated with one first resource among the multiple first resources, and two first resources associated with two relay network devices among the multiple relay network devices partially overlap or do not overlap.

20. The method according to any one of claims 16 to 19, characterized in that: The first information further includes: identification information of the relay network device, identification information of the first target network device, path information from the source network device to the first target network device, and delay information from the source network device to the first target network device.

21. The method according to any one of claims 16 to 20, characterized in that: The first information further includes: information for indicating that the transmission mode of the first information by the relay network device is a first transmission mode; The first transmission mode indicates that: the relay network device relays and forwards the first information, and obtains indication information of the first resource in the first information.

22. The method according to any one of claims 16 to 21, characterized in that: The method further comprises: receiving first switching response information from the first target network device; The first switching response information is sent to the source network device, where the first switching response information is response information of the first information, and the first switching response information includes information for indicating that the transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the first switching response information.

23. The method according to any one of claims 16 to 22, characterized in that: The second information further includes: information for indicating that the transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the second information.

24. The method according to any one of claims 16 to 23, characterized in that: The second information includes: a switching response, a sequence number SN status transmission, and at least one of the context of the terminal device.

25. The method according to any one of claims 16 to 24, characterized in that: The first information is also used to request to switch the terminal device from the source network device to the second target network device. The first information also includes indication information of a second resource, and the second resource is used by the relay network device to transmit information associated with the switching process to the second target network device.

26. The method of claim 25, wherein: The first information also includes: information for indicating the second target network device; information for indicating the information transmission path from the source network device to the second target network device; and information for indicating the relay network device in the information transmission path from the source network device to the second target network device.

27. The method according to any one of claims 25-26, characterized in that The method further comprises: receiving second switching response information from the second target network device, where the second switching response information is response information to the first information, and the second switching response information includes information for indicating that a transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the second switching response information; The second switching response information is sent to the source network device.

28. The method according to any one of claims 16 to 27, characterized in that The first information also includes: context information of the terminal device; The first information further includes information for indicating the following: the relay network device needs to obtain the context information of the terminal device from the first information; The method further comprises: The context information of the terminal device is obtained from the first information.

29. The method according to any one of claims 16 to 28, characterized in that The first resource is associated with at least one of the following: mobile interruption time information of the terminal device; uplink service arrival rate of the terminal device; downlink service arrival rate of the terminal device; or the type of the terminal device.

30. The method according to any one of claims 16 to 29, characterized in that: The sending the first information to the first target network device includes: If it is determined that the first path cannot be used to send the first information, determining a second path; The first information is sent to the first target network device based on the second path.

31. A communication method, characterized in that: The method is applicable to a terminal device, and the method comprises: Acquire fourth information, the fourth information including at least one of a priority of the terminal device, a capability of the terminal device, a quality of service requirement of the terminal device, and a quality of service experience of the terminal device; The fourth information is sent to the source network device, and the fourth information is used by the source network device to determine the first resource. The information transmission path from the source network device to the first target network device includes at least one relay network device, and the first resource is used for the relay network device in the at least one relay network device to transmit information associated with the switching process.

32. The method of claim 31, wherein: The indication information of the first resource includes at least one of the following: Information indicating a time period; Information indicating bandwidth resources; Information indicating the transmission rate; Information used to indicate quality of service requirements; Information indicating the quality of service experience; Information indicating location; Information indicating polarization.

33. The method according to any one of claims 31 to 32, characterized in that The first resource is used to transmit information associated with a handover process of a first type of terminal device; The first type of terminal device is associated with at least one of: a priority of the terminal device, a capability of the terminal device, a quality of service requirement of the terminal device, or a quality of service experience of the terminal device.

34. The method according to any one of claims 31 to 33, characterized in that The method further comprises: receiving fifth information, the fifth information indicating a relay network device storing context information of the terminal device; Based on the fifth information, an information transmission path between the terminal device and at least one relay network device is determined.

35. A communication method, characterized in that: The method is applicable to a first target network device, and the method comprises: receiving first information, the first information being used to request switching a terminal device from a source network device to the first target network device, the first information comprising indication information of a first resource, the information transmission path from the source network device to the first target network device comprising at least one relay network device, the first resource being used for a relay network device in the at least one relay network device to transmit information associated with a switching process; Second information is received, where the second information belongs to information associated with the switching process.

36. The method of claim 35, wherein: The indication information of the first resource includes at least one of the following: Information indicating a time period; Information indicating bandwidth resources; Information indicating the transmission rate; Information used to indicate quality of service requirements; Information indicating the quality of service experience; Information indicating the location of a relay network device; Information indicating polarization; or Used to indicate the information carried.

37. The method according to any one of claims 35 to 36, characterized in that The first resource is used to transmit information associated with a handover process of a first type of terminal device; The first type of terminal device is associated with at least one of: a priority of the terminal device, a capability of the terminal device, a quality of service requirement of the terminal device, or a quality of service experience of the terminal device.

38. The method according to any one of claims 35 to 37, characterized in that The information transmission path from the source network device to the first target network device includes multiple relay network devices, the first information includes indication information of multiple first resources, the multiple relay network devices are associated with one first resource among the multiple first resources, and two first resources associated with two relay network devices among the multiple relay network devices partially overlap or do not overlap.

39. The method according to any one of claims 35 to 38, characterized in that The first information also includes: identification information of a relay network device associated with a first resource among the multiple first resources, identification information of the first target network device, path information from the source network device to the first target network device, and delay information from the source network device to the first target network device.

40. The method according to any one of claims 35 to 39, characterized in that The first information includes: information for indicating that the transmission mode of the first information by the relay network device is a first transmission mode; The first transmission mode includes: a relay network device relays and forwards the first information, and obtains indication information of the first resource in the first information.

41. The method according to any one of claims 35 to 40, characterized in that The method further comprises: Sending first switching response information, where the first switching response information is response information of the first information, the first switching response information includes information for indicating that the transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the first switching response information.

42. The method according to any one of claims 35 to 41, characterized in that The second information further includes: information for indicating that the transmission mode of the relay network device is a second transmission mode, and the second transmission mode indicates that the relay network device relays and forwards the second information.

43. The method according to any one of claims 35 to 42, characterized in that The second information includes: a switching response, a sequence number SN status transmission, or at least one of the context of the terminal device.

44. The method according to any one of claims 35 to 43, characterized in that The first information also includes: context information of the terminal device; The first information further includes information for indicating that a relay network device in the at least one relay network device needs to obtain context information of the terminal device from the first information.

45. The method according to any one of claims 35 to 44, characterized in that The first resource is associated with at least one of the following: mobile interruption time information of the terminal device; uplink service arrival rate of the terminal device; downlink service arrival rate of the terminal device; or the type of the terminal device.

46. ​​A communication device, characterized in that: Comprising means for performing the method as claimed in any one of claims 1 to 45.

47. A communication device, characterized in that: It includes at least one processor and an interface circuit, wherein the interface circuit is used to receive signals from other communication devices and transmit them to the at least one processor or send signals from the at least one processor to other communication devices, and the at least one processor is used to implement the method as described in any one of claims 1 to 45 through logic circuits or executing code instructions.

48. A communication device, characterized in that: The method comprises at least one processor, wherein the at least one processor is used to implement the method according to any one of claims 1 to 45 through logic circuits or executing code instructions.

49. A computer-readable storage medium, characterized in that The storage medium stores a computer program or instruction, and when the computer program or instruction is executed by the communication device, the method as claimed in any one of claims 1 to 45 is implemented.

50. A computer program product, characterized in that The computer program product stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a computer, the computer is caused to perform the method according to any one of claims 1 to 45.

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