Communication method and apparatus

Abstract

The communication method and apparatus provided in this application relate to the field of communication and can improve user experience. The method includes a first network device sending a first message to a second network device and receiving a second message from the second network device. The first message requests a handover of a first terminal device to the second network device, where the first network device is the source network device of the first terminal device, and the second network device is a candidate target network device for the first terminal device. The second message indicates a refusal to handover and includes indication information about the reason for the refusal. The reasons for the refusal include: the first terminal device is located within a first area, or the first terminal device will move to the first area within a first time period; wherein the second network device prohibits communication within the first area.

Description

Technical Field

[0001] This application relates to the field of communications, and more particularly to communication methods and apparatus. Background Technology

[0002] Satellite communication, also known as non-terrestrial networks (NTN) communication, has significant advantages such as global coverage, long-distance transmission, flexible networking, convenient deployment, and no geographical limitations. It has been widely used in many fields such as maritime communication, positioning and navigation, disaster relief, scientific experiments, video broadcasting, and Earth observation.

[0003] Specifically, based on the satellite's orbital altitude, satellite communication systems can be divided into geostationary earth orbit (GEO) satellite communication systems, medium earth orbit (MEO) satellite communication systems, and low earth orbit (LEO) satellite communication systems. Satellites within GEO can be called geosynchronous orbit (GSO) satellites, and satellites within LEO can be called LEO satellites.

[0004] In satellite communication systems, in order to ensure the communication of high-orbit satellites, the International Telecommunication Union stipulates that low-orbit satellites must give way to high-orbit satellites.

[0005] Specifically, a certain area (e.g., an area within a certain angle defined by the line connecting high-orbit and low-orbit satellites) is designated as a avoidance zone. Within this zone, communication (such as signal transmission and reception) by low-orbit satellites is prohibited; thus, high-orbit satellites are avoided within the avoidance zone. Consequently, terminal devices within the avoidance zone are unable to transmit data, resulting in a degraded user experience. Summary of the Invention

[0006] This application provides a communication method and apparatus that can improve user experience.

[0007] In a first aspect, embodiments of this application provide a communication method, which can be executed by a first communication device. Unless otherwise specified, the "first communication device" in this application can be a first network device, a component applicable to the first network device (e.g., a communication module, processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the first network device. Taking the first communication device as the first network device as an example, the method includes: sending a first message to a second network device and receiving a second message from the second network device. The first message requests a switch from a first terminal device to the second network device. The first network device is the source network device of the first terminal device, and the second network device is a candidate target network device for the first terminal device. The second message indicates a refusal to switch, and includes indication information of the reason for the refusal. The reasons for the refusal include: the first terminal device is located within a first area; or, the first terminal device will move to the first area within a first time period; or, the second network device is prohibited from communication within the first area.

[0008] Based on this scheme, when a terminal device (such as the first terminal device) meets the handover conditions, its source network device (i.e., the first network device) can send a handover request to a candidate target network device (such as the second network device). The candidate target network device can then choose whether to agree to the handover based on its own circumstances. For example, the candidate target network device can determine whether the terminal device is located in its avoidance zone (where communication is prohibited) or whether it is about to enter the avoidance zone. If so, it can reject the handover request. This avoids the terminal device being unable to transmit data after handover to the candidate target network device, thus preventing a decline in user experience. Furthermore, the terminal device can choose to handover to other candidate target network devices to ensure data transmission and improve the user experience.

[0009] In one possible design, the first area serves as a clearance zone for the second network device.

[0010] In one possible design, the first message is a switch request message.

[0011] In one possible design, the second message is either a handover rejection message or a handover preparation failure message.

[0012] Based on the two possible designs mentioned above, the first message and / or the second message can reuse relevant messages defined in the existing protocol (such as the first message being a handover request message and the second message being a handover rejection message or a handover preparation failure message) to implement the solution of this application, thereby eliminating the need to specifically configure corresponding parameters for the first message and the second message and simplifying the complexity of implementing this application.

[0013] In one possible design, the method further includes: determining, based on the second message, that the first terminal device does not perform a handover.

[0014] Based on this possible design, after determining that the second network device rejects the handover of the first terminal device, the first network device can choose not to send a handover instruction to the first terminal device, that is, the first terminal device does not perform the handover, thereby avoiding the first terminal device being unable to transmit data after handover to the candidate target network device, which would lead to a decline in user experience.

[0015] In one possible design, the method further includes: sending a third message to a third network device, the third message being used to request the first terminal device to switch to the third network device, the third network device being a candidate target network device for the first terminal device, and the second network device being different from the third network device.

[0016] Based on this possible design, after determining that the second network device rejects the handover of the first terminal device, the first network device can send a handover request (i.e., a third message) to other candidate target network devices (such as a third network device) in order to switch to the other candidate target network device, so as to ensure the data transmission of the terminal device and improve the user experience.

[0017] In one possible design, the method further includes: determining a second region based on the second message and the location of the first terminal device; determining whether the second terminal device is located within the second region if the second terminal device meets the handover conditions and the second network device is a candidate target network device; and determining that the second terminal device does not handover to the second network device if the second terminal device is located within the second region.

[0018] Based on this possible design, after receiving the second message, the first network device can infer the avoidance area of ​​the second network device based on the location of the first terminal device (e.g., determine the second area). Then, if other terminal devices (e.g., the second network device) subsequently meet the handover conditions and want to switch to the second network device, the first network device can directly determine whether to switch those other terminal devices to the second network device based on the second area. Specifically, for the second terminal device located in the second area, even if the first network device sends a handover request to the second network device, the second network device will refuse the handover because the second terminal device is located in the first area, or is about to enter the first area. Therefore, the first network device can directly determine whether to send a handover request to the second network device based on whether the second terminal device is located in the second area. If the second terminal device is located in the second area, there is no need to send a handover request; the first network device can directly determine not to switch to the second network device, thereby reducing signaling interaction between the first and second network devices and saving signaling overhead.

[0019] In one possible design, the first terminal device is located within the coverage area of ​​the first wave position, which is one of multiple wave positions of the second network device; correspondingly, the second area includes the coverage area of ​​the first wave position.

[0020] Based on this possible design, it can be understood that the avoidance zone typically contains at least one wavelet, and for a wavelet in a non-avoidance zone adjacent to that at least one wavelet, it can be assumed that a terminal device within the coverage area of ​​that wavelet is about to enter the avoidance zone. Therefore, when the first network device guesses the avoidance zone of the second network device, it can guess at the wavelet level, that is, the second area contains one of the multiple wavelets of the second network device. This improves the accuracy of the first network device's guess.

[0021] In one possible design, the indication information for the reason for refusing to switch includes a first reason value, which indicates that the first terminal device is located in a first area, or that the first reason value indicates that the first terminal device will move to the first area within a first time period.

[0022] Based on the two possible designs described above, it is understandable that normal communication for the terminal device cannot be guaranteed when it is located within the network device's avoidance zone (such as the first zone) or is about to enter the network device's avoidance zone. Therefore, when the first terminal device is located within the first zone or is about to enter the first zone, the second network device may consider rejecting the first terminal device's handover request, thereby preventing the first terminal device from being unable to communicate normally after switching to the second network device.

[0023] In one possible design, the indication information for the reason for refusing to switch includes a first reason value, which is the reason value corresponding to the reason for refusing to switch among multiple reasons for refusing to switch in a first correspondence relationship. The first correspondence relationship contains the correspondence between multiple reason values ​​and multiple reasons for refusing to switch.

[0024] In one possible design, before receiving the second message, the method further includes: sending a fourth message to a second network device, the fourth message being used to indicate the location information of the first terminal device, the location information of the first terminal device being used to determine the second message.

[0025] In one possible design, the first message is also used to indicate the location information of the first terminal device, and the location information of the first terminal device is used to determine the second message.

[0026] Based on the two possible designs described above, the first network device can inform the second network device of the location of the first terminal device, thereby facilitating the second network device to determine whether the first terminal device is located within the first area, or whether the first terminal device is about to enter the first area; and further determine the second message. In other words, it facilitates the second network device in determining the second message.

[0027] In one possible design, the location information of the first terminal device includes information about a first wave position, which is one of multiple wave positions of the second network device, and the first terminal device is located within the coverage area of ​​the first wave position.

[0028] Based on this possible design, it is understandable that normal communication of the terminal device cannot be guaranteed when the terminal device is located within the avoidance zone of the network device (such as the first zone), or when the terminal device is about to enter the avoidance zone of the network device. Therefore, the first network device can inform the second network device which of the multiple wavelengths of the second network device the first terminal device is within its coverage area, thereby reducing the complexity of the second network device in determining the second message and improving feedback efficiency.

[0029] Secondly, embodiments of this application provide a communication method, which can be executed by a second communication device. Unless otherwise specified, the "second communication device" in this application can be a second network device, a component applicable to the second network device (e.g., a communication module, processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the second network device. The method includes: receiving a first message from a first network device and sending a second message to the first network device. The first message requests a switch from a first terminal device to the second network device, where the second network device is a candidate target network device for the first terminal device, and the first network device is the source network device for the first terminal device. The second message indicates a refusal to switch, including indication information of the reason for the refusal. The reasons for the refusal include: the first terminal device is located within a first area; or, the first terminal device will move to the first area within a first time period; or, the second network device is prohibited from communication within the first area.

[0030] Based on this scheme, when a terminal device (such as the first terminal device) meets the handover conditions, its source network device (i.e., the first network device) can send a handover request to a candidate target network device (such as the second network device). The candidate target network device can then choose whether to agree to the handover based on its own circumstances. For example, the candidate target network device can determine whether the terminal device is located in its avoidance zone (where communication is prohibited) or whether it is about to enter the avoidance zone. If so, it can reject the handover request. This avoids the terminal device being unable to transmit data after handover to the candidate target network device, thus preventing a decline in user experience. Furthermore, the terminal device can choose to handover to other candidate target network devices to ensure data transmission and improve the user experience.

[0031] In one possible design, the first area serves as a clearance zone for the second network device.

[0032] In one possible design, the first message is a switch request message.

[0033] In one possible design, the second message is a handover rejection message, or the second message is a handover preparation failure message.

[0034] In one possible design, the indication information for the reason for refusing to switch includes a first reason value, which indicates that the first terminal device is located in a first area, or that the first reason value indicates that the first terminal device will move to the first area within a first time period.

[0035] In one possible design, the indication information for the reason for refusing to switch includes a first reason value, which is the reason value corresponding to the reason for refusing to switch among multiple reasons for refusing to switch in a first correspondence relationship. The first correspondence relationship contains the correspondence between multiple reason values ​​and multiple reasons for refusing to switch.

[0036] In one possible design, before sending the second message, the method further includes: receiving a fourth message from a first network device, the fourth message indicating the location information of the first terminal device; and sending the second message, including: sending the second message according to the fourth message.

[0037] In one possible design, the first message is also used to indicate the location information of the first terminal device; sending the second message includes: sending the second message according to the first message.

[0038] In one possible design, the location information of the first terminal device includes information about a first wave position, which is one of multiple wave positions of the second network device, and the first terminal device is located within the coverage area of ​​the first wave position.

[0039] The technical effects of any design in the second aspect can be referenced from the technical effects of the corresponding design in the first aspect, and will not be elaborated here.

[0040] Thirdly, embodiments of this application provide a communication method, which can be executed by a first communication device. Unless otherwise specified, the "first communication device" in this application can be a first network device, a component applicable to the first network device (e.g., a communication module, processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the first network device. The method includes: acquiring a first area, where a second network device prohibits communication within the first area, the second network device being a candidate target network device for a first terminal device, and the first network device being a source network device for the first terminal device; determining whether the terminal device is located within the first area, or whether the terminal device will move to the first area within a first time period, when the terminal device meets the handover conditions; and determining whether the terminal device should handover to the second network device based on the judgment result. Specifically, if the judgment result is that the terminal device is not located within the first area and will not move to the first area within the first time period, the first network device can send a handover request to the second network device; if the judgment result is that the terminal device is located within the first area, or will move to the first area within the first time period, the first network device determines that the terminal device will not handover to the second network device.

[0041] Based on this scheme, the source network device of the terminal device (i.e., the first network device) can pre-observe the avoidance zones of other network devices (e.g., the avoidance zone of the second network device is the first zone, where communication is prohibited for the network device within the avoidance zone). Therefore, when the terminal device meets the handover conditions and needs to switch to the second network device, it can first determine whether the terminal device is located within the avoidance zone, or whether the terminal device is about to enter the avoidance zone. If so, it means that even if the terminal device switches to the second network device, normal communication cannot be guaranteed. Therefore, the first network device considers not switching the terminal device to the second network device, thus avoiding sending a handover request to the second network device, reducing signaling interaction between the first and second network devices, and saving signaling overhead. Furthermore, the terminal device can choose to switch to other candidate target network devices to ensure data transmission and improve user experience.

[0042] In one possible design, obtaining the first area includes receiving a fifth message from a second network device, the fifth message indicating the first area.

[0043] In one possible design, the candidate target network device for the first terminal device also includes a third network device, and the method further includes: obtaining a second area, in which the third network device prohibits communication; determining whether the terminal device is located in the third area, or whether the terminal device will move to the third area during a second time period; and determining that the terminal device will not switch to the third network device if the terminal device is located in the third area, or if the terminal device will move to the third area during the second time period.

[0044] Based on this possible design, after determining that the second network device rejects the handover of the first terminal device, the first network device can choose whether to handover to other candidate target network devices (such as the third network device). That is, it can determine whether the terminal device is located in the third area, or whether the terminal device will move to the third area during the second time period. In this way, if the terminal device is not located in the third area and will not move to the third area during the second time period, it can handover to the third network device to ensure the data transmission of the terminal device and improve the user experience.

[0045] In one possible design, acquiring the second area includes receiving a sixth message from a third network device, the sixth message indicating the third area.

[0046] Fourthly, a communication device is provided for implementing various methods. This communication device can be a first communication device as described in the first or third aspect, or a second communication device as described in the second aspect, such as a device, chip, or chip system. The communication device includes modules, units, or means corresponding to the implementation of the methods, which can be implemented in hardware, software, or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the functions.

[0047] In some possible designs, the communication device may include a processing module and a transceiver module. The processing module can be used to implement the processing functions in any of the above aspects and any possible implementations thereof. The transceiver module may include a receiving module and a transmitting module, respectively used to implement the receiving function and the transmitting function in any of the above aspects and any possible implementations thereof.

[0048] In some possible designs, the transceiver module can consist of transceiver circuits, transceivers, transceivers, or communication interfaces.

[0049] Fifthly, a communication device is provided, comprising: a processor and a memory; the memory is used to store computer instructions, which, when executed by the processor, cause the communication device to perform the method described in any aspect. The communication device may be a first communication device as described in the first or third aspect, or a second communication device as described in the second aspect, such as a device, chip, or chip system. The communication device includes modules, units, or means corresponding to the implementation of the method, which may be implemented in hardware, software, or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the function.

[0050] A sixth aspect provides a communication device, comprising: a processor and a communication interface; the communication interface being used to communicate with a module outside the communication device; the processor being used to execute a computer program or instructions to cause the communication device to perform the method described in any aspect. The communication device may be a first communication device as described in the first or third aspect, or a second communication device as described in the second aspect, such as a device, chip, or chip system. The communication device includes modules, units, or means corresponding to the implementation of the method, which may be implemented in hardware, software, or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the function.

[0051] A seventh aspect provides a communication device, comprising: at least one processor; the processor being configured to execute a computer program or instructions to cause the communication device to perform the method described in any aspect. The communication device may be a first communication device as described in the first or third aspect, or a second communication device as described in the second aspect, or a device included in the first or second communication device, such as a chip or chip system. The communication device includes modules, units, or means corresponding to the implementation of the method, which may be implemented in hardware, software, or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the functions described.

[0052] In some possible designs, the communication device includes a memory for storing at least one of necessary programs, instructions, or data. The memory may be coupled to the processor, or it may be independent of the processor.

[0053] In some possible designs, when the device is a chip system, it can be composed of chips or contain chips and other discrete components.

[0054] It is understandable that when the communication device provided in any of the fourth to seventh aspects is a chip, the sending action / function of the communication device can be understood as outputting information, and the receiving action / function of the communication device can be understood as inputting information.

[0055] The aforementioned first communication device may be a first network device, or a communication module within the first network device, or a circuit or chip within the first network device responsible for communication functions, or a functional module within the first network device capable of calling and executing a program. And / or, the aforementioned second communication device may be a second network device, or a communication module within the second network device, or a circuit or chip within the second network device responsible for communication functions, or a functional module within the second network device capable of calling and executing a program.

[0056] Eighthly, a computer-readable storage medium is provided that stores a computer program or instructions that, when executed on a communication device, enable the communication device to perform the method described in either aspect.

[0057] In a ninth aspect, a computer program product containing instructions is provided that, when run on a communication device, enables the communication device to perform the method described in either aspect.

[0058] In a tenth aspect, a communication system is provided, comprising a first communication device (e.g., a first network device, a chip or chip system applied to the first network device) as described in the first or third aspect, and a second communication device (e.g., a second network device, a chip or chip system applied to the second network device) as described in the second aspect.

[0059] The technical effects of any of the design methods in aspects four through ten can be found in the technical effects of the different design methods in aspects one through three above, and will not be repeated here. Attached Figure Description

[0060] Figure 1 A schematic diagram of a cell handover process provided in an embodiment of this application is shown;

[0061] Figure 2 A schematic diagram of a cell handover scenario provided in an embodiment of this application is shown;

[0062] Figure 3 This illustration shows a schematic diagram of an avoidance area provided in an embodiment of this application;

[0063] Figure 4 A schematic diagram illustrating another cell handover scenario provided in an embodiment of this application is shown;

[0064] Figure 5 This paper illustrates a schematic diagram of the architecture of a communication system provided in an embodiment of this application.

[0065] Figure 6 This invention illustrates a schematic diagram of the architecture of another communication system provided in an embodiment of this application;

[0066] Figure 7 This diagram illustrates a possible application framework in an O-RAN communication system.

[0067] Figure 8 A schematic diagram of a possible application framework in an NTN communication system is shown.

[0068] Figure 9 , Figures 11-13 A flowchart illustrating the communication method provided in an embodiment of this application is shown;

[0069] Figure 10 This illustration shows a schematic diagram of the wave positions included in a network device according to an embodiment of this application;

[0070] Figure 14 This paper shows a schematic diagram of the structure of a communication device provided in an embodiment of this application;

[0071] Figure 15A schematic diagram of another communication device provided in an embodiment of this application is shown;

[0072] Figure 16 A schematic diagram of the structure of another communication device provided in an embodiment of this application is shown. Detailed Implementation

[0073] In the description of this application, unless otherwise stated, " / " indicates that the objects before and after are in an "or" relationship. For example, A / B can mean A or B. "And / or" in this application is merely a description of the relationship between the related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural.

[0074] In the description of this application, unless otherwise stated, "multiple" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of a single item or a plurality of items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0075] Furthermore, to facilitate a clear description of the technical solutions in the embodiments of this application, the terms "first" and "second" are used in the embodiments of this application to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" are not necessarily different.

[0076] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner to facilitate understanding.

[0077] It is understood that the term "embodiment" used throughout the specification means that a specific feature, structure, or characteristic related to an embodiment is included in at least one embodiment of this application. Therefore, various embodiments throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It is understood that in the various embodiments of this application, the sequence number of each process does not imply the order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0078] It is understood that the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.

[0079] It is understood that in this application, "...when" and "if" both refer to the corresponding processing that will be carried out under certain objective circumstances, and are not limited to a specific time, nor do they require a judgment action to be performed during implementation, nor do they imply any other limitations.

[0080] It is understood that some optional features in the embodiments of this application can be implemented independently in certain scenarios without relying on other features, such as the current solution on which they are based, to solve the corresponding technical problems and achieve the corresponding effects. Alternatively, they can be combined with other features as needed in certain scenarios. Correspondingly, the apparatus given in the embodiments of this application can also implement these features or functions, which will not be elaborated here.

[0081] It is understood that in this application, "instruction" can include direct and indirect instructions, as well as explicit and implicit instructions. When describing "a certain instruction information instructs A" or "instruction information of A," it can include whether the instruction information directly or indirectly instructs A, but does not necessarily mean that the instruction information carries A. The information indicated by a certain piece of information is called the information to be instructed. In the specific implementation process, there are many ways to instruct the information to be instructed, such as, but not limited to, directly instructing the information to be instructed, such as the information to be instructed itself or its index. It can also indirectly instruct the information to be instructed by instructing other information, where there is a relationship between the other information and the information to be instructed. It can also instruct only a part of the information to be instructed, while the other parts are known or pre-agreed upon. For example, the instruction of specific information can be achieved by using a pre-agreed (e.g., protocol-defined) arrangement of various information, thereby reducing instruction overhead to some extent. At the same time, the common parts of various information can be identified and uniformly indicated to reduce the instruction overhead caused by individually indicating the same information. Furthermore, the specific instruction method can also be any existing instruction method, such as, but not limited to, the above-mentioned instruction methods and their various combinations. As described above, for example, when multiple pieces of information of the same type need to be indicated, the indication methods for different pieces of information may differ. In specific implementation, the required indication method can be selected according to specific needs. This application embodiment does not limit the selected indication method; therefore, the indication methods involved in this application embodiment should be understood to cover various methods that enable the party to be indicated to obtain the information to be indicated. The information to be indicated can be sent as a whole or divided into multiple sub-information pieces and sent separately. Furthermore, the sending period or timing of these sub-information pieces can be the same or different. This application does not limit the specific sending method. The sending period or timing of these sub-information pieces can be predefined, for example, predefined according to a protocol, or configured by the transmitting device by sending configuration information to the receiving device.

[0082] In this application, "send" and "receive" indicate the direction of signal transmission. For example, "send information to XX" can be understood as the destination of the information being XX, which can include direct transmission via the air interface or indirect transmission via the air interface from other units or modules. "Receive information from YY" can be understood as the source of the information being YY, which can include direct reception from YY via the air interface or indirect reception from YY via the air interface from other units or modules. "Send" can also be understood as the "output" of the chip interface, and "receive" can also be understood as the "input" of the chip interface. In other words, sending and receiving can occur between devices, such as between RAN nodes and terminal devices, or within a device, such as between components, modules, chips, software modules, or hardware modules within the device via buses, traces, or interfaces.

[0083] In this application, "predefined" can refer to a standard protocol predefined, or it can refer to something agreed upon or negotiated in advance between devices. In this application, "protocol" can refer to a standard protocol in the field of communications, such as the 5G protocol, the NR protocol, and related protocols applied in future communication systems; this application does not limit this. "Predefined" can include predefined terms, such as protocol definitions. "Preconfiguration" can be implemented by pre-storing corresponding codes, tables, or other methods that can be used to indicate relevant information in the device; this application does not limit the implementation method, for example.

[0084] In this application, the terms "exemplarily," "for example," etc., are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as an "example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the term "example" is intended to present concepts in a concrete manner. In the embodiments of this application, "of," "corresponding, relevant," and "corresponding" may sometimes be used interchangeably, and it should be noted that their intended meanings are consistent unless their distinction is emphasized.

[0085] In this application, unless otherwise specified, the same or similar parts between the various embodiments can be referred to each other. Unless otherwise specified or logically conflicting, at least one of the terms or descriptions in the various embodiments of this application is consistent and can be referenced mutually. Different embodiments can be combined to form new embodiments based on their inherent logical relationships. The following descriptions of the embodiments of this application do not constitute a limitation on the scope of protection of this application.

[0086] Before describing the embodiments of this application, the technical terms involved in the embodiments of this application will be described.

[0087] Cell handover: In 5th generation (5G) or new radio (NR) systems, the cell handover process may include the following: Figure 1 The steps shown are as follows:

[0088] S101. The source base station of the terminal device (also known as the serving base station before handover) can send measurement configuration information to the terminal device. Correspondingly, the terminal device receives the measurement configuration information from the source base station.

[0089] Optionally, the measurement configuration information may include the measurement object, report configuration, measurement gap, etc.

[0090] For example, the reporting configuration is used to indicate the event that triggers the reporting of a measurement report; for example, the event may include an event that measures distance (referred to as a distance event) or an event that measures signal quality (referred to as a signal quality event).

[0091] The distance events can include events such as D1 and D2. Event D1 occurs when the distance between the neighboring cell (or the base station controlling the neighboring cell, referred to as the neighboring station) and the UE is greater than the distance between the serving cell (or the source base station) and the UE; or when the distance between the neighboring cell (or the base station controlling the neighboring cell, referred to as the neighboring station) and the UE is greater than the distance between the serving cell (or the source base station) and the UE, and the difference between these two distances is greater than a preset distance threshold. For ease of description, the following embodiments will uniformly use event D1 as an example to introduce measurement reporting triggered by distance events, and will not be elaborated further.

[0092] Signal quality events include events A1, A2, A3, A4, and A5. Event A1 occurs when the signal quality of the serving cell is greater than a first preset signal quality threshold; event A2 occurs when the signal quality of the serving cell is less than a second preset signal quality threshold; event A3 occurs when the signal quality of a neighboring cell is greater than the signal quality of the serving cell; event A4 occurs when the signal quality of a neighboring cell is greater than a third preset signal quality threshold; and event A5 occurs when the signal quality of the serving cell is less than the second preset signal quality threshold, and the signal quality of a neighboring cell is greater than the third preset signal quality threshold. For ease of description, the following embodiments will uniformly use event A3 as an example to introduce measurement reporting triggered by signal quality events, and will not be elaborated further here.

[0093] For example, the measurement interval can also be called the measurement gap, which is a time interval dedicated to neighbor cell measurements. That is, the terminal device needs to measure the signal quality of the neighbor cell within this measurement gap. Specifically, within the measurement gap, the terminal device suspends data transmission with its serving cell (i.e., the source base station) and accesses the neighbor cell to measure its signal quality; after the measurement gap ends, the terminal device continues to access its serving cell and continues data transmission with the serving cell.

[0094] Optionally, the terminal equipment includes, but is not limited to, user equipment (UE).

[0095] S102. The terminal device measures the object to be measured based on the measurement configuration information.

[0096] For example, depending on the event that triggers the measurement report, the terminal device can perform corresponding measurements based on that event.

[0097] As an example, this event includes a distance event. In this example, the terminal device can measure the distance between itself and neighboring cells, obtain the measurement result, and determine whether the distance event is satisfied.

[0098] Taking the UE accessing the base station via satellite, or the base station being deployed on a satellite as an example, such as Figure 2 As shown, the UE moves to the overlapping area of ​​satellite #1 and satellite #2 (i.e., the UE is simultaneously within the signal coverage area of ​​both satellite #1 and satellite #2); where satellite #2 is the UE's source base station, and satellite #1 is the UE's neighboring base station. The UE can measure its distance to satellite #1 and obtain the measurement result. Figure 2 It can be seen that the distance between the UE and satellite #1 is greater than the distance between the UE and satellite #2; therefore, the measurement result of satellite #2 satisfies the distance event.

[0099] In another example, the event is a signal quality event. In this example, the terminal device can measure the signal quality of neighboring cells within the measurement gap, obtain the measurement results, and determine whether the signal quality event is satisfied.

[0100] S103. The terminal device sends a measurement report to the source base station. Correspondingly, the source base station receives the measurement report from the terminal device.

[0101] Specifically, when a terminal device measures a certain object (such as a neighboring cell) within a certain time period and the measurement result meets the event indicated by the reporting configuration, it indicates that the measurement result meets the event. Therefore, the terminal device can report a measurement report; the measurement report contains the measurement result.

[0102] S104. The source base station determines the target cell based on the measurement report.

[0103] For example, the source base station evaluates the measurement results in the measurement report to determine the target cell. The target cell is controlled by the target base station.

[0104] S105. The source base station sends a handover request to the target base station. Correspondingly, the target base station receives the handover request from the source base station.

[0105] For example, a handover request includes information required for handover, such as the identifier (ID) of the target cell.

[0106] S106. Access control is performed on the target base station.

[0107] Optionally, access control can be understood as determining whether terminal devices are supported to access the target base station.

[0108] When supporting terminal devices to access the target base station, step S107 is executed:

[0109] S107. The target base station sends a handover confirmation message to the source base station. Correspondingly, the source base station receives the handover confirmation message from the target base station.

[0110] For example, the handover confirmation information includes configuration information related to the target cell (such as the target cell ID).

[0111] S108. The source base station sends an RRC reconfiguration message (handover command) to the terminal device. Correspondingly, the terminal device receives the RRC reconfiguration message from the source base station.

[0112] S109. The terminal device performs a handover based on the RRC reconfiguration message.

[0113] For example, the terminal device can perform RRC reconfiguration based on the RRC reconfiguration information. After the RRC reconfiguration is completed, the terminal device sends a message indicating successful RRC reconfiguration to the target base station. Correspondingly, the target base station receives the message from the terminal device indicating successful RRC reconfiguration. At this point, the handover on the radio access network (RAN) side of the terminal device can be considered successful.

[0114] Optionally, in this application, "handover" generally refers to the handover between base station control and terminal equipment control in RRC connection state, cell changes, etc.

[0115] Non-terrestrial networks (NTN): 5G NR technology is evolving from release 18 (Rle18 / R18) to R19. Simultaneously, NR technology has moved from the standardization phase to commercial deployment. The initial research on the NR standard protocol was for wireless communication technologies designed for terrestrial cellular network scenarios, capable of providing users with low latency, ultra-reliability, ultra-high speed, and massive connectivity wireless communication services. However, cellular networks cannot achieve seamless global coverage. For example, in areas without terrestrial base stations, such as ocean areas, polar regions, and rainforests, voice and data services cannot be provided to areas covered by cellular networks.

[0116] Compared to terrestrial communications, NTN communications offer significant advantages such as global coverage, long-distance transmission, flexible networking, convenient deployment, and freedom from geographical limitations. It has been widely applied in various fields including maritime communications, positioning and navigation, disaster relief, scientific experiments, video broadcasting, and Earth observation. NTN networks can be integrated with terrestrial networks, leveraging their respective strengths to create a seamless, globally integrated sea, land, air, space, and ground communications network, meeting the diverse and ubiquitous service needs of users.

[0117] Depending on the altitude of the flight platform above the ground, the NTN can include a low altitude platform (LAP) subnetwork, a high altitude platform (HAP) subnetwork, and a satellite communication subnetwork.

[0118] For example, in a LAP subnetwork, base stations or base station functions are deployed on low-altitude flight platforms (e.g., drones) at an altitude of 0.1km to 1km above the ground to provide coverage for terminals; in a HAP subnetwork, base stations or base station functions are deployed on high-altitude flight platforms (e.g., aircraft) at an altitude of 8km to 50km above the ground to provide coverage for terminals; and in a SATCOM subnetwork, base stations or base station functions are deployed on satellites at an altitude of more than 50km above the ground to provide coverage for terminals. Satellite communication, with its significant advantages such as global coverage, long-distance transmission, flexible networking, convenient deployment, and lack of geographical limitations, has been widely applied in various fields including maritime communication, positioning and navigation, disaster relief, scientific experiments, video broadcasting, and Earth observation.

[0119] Furthermore, based on the satellite's orbital altitude, satellite communication systems can be divided into geosynchronous orbit (GSO) satellite communication systems, medium Earth orbit (MEO) satellite communication systems, and low-earth orbit (LEO) satellite communication systems. GSO can also be referred to as geostationary earth orbit (GEO).

[0120] For example, satellites providing services for GSO satellite communication systems can also be simply referred to as high-orbit satellites, and further, high-orbit satellites can also be directly referred to as GSO satellites; similarly, satellites providing services for LEO satellite communication systems can also be simply referred to as low-orbit satellites, and further, low-orbit satellites can also be directly referred to as LEO.

[0121] It should be understood that the satellite mentioned in the embodiments of this application may be a satellite base station, or may include an orbital receiver or repeater for relaying information, or a network-side device mounted on a satellite.

[0122] In satellite communication systems, in order to ensure the communication of high-orbit satellites, the International Telecommunication Union stipulates that low-orbit satellites must give way to high-orbit satellites.

[0123] Specifically, a certain area (e.g., an area within a certain angle defined by the line connecting high-orbit and low-orbit satellites) is designated as a avoidance zone. Within this zone, communication (such as transmitting and receiving signals) by low-orbit satellites is prohibited; thus, high-orbit satellites are avoided within the avoidance zone. The avoidance zone can be a spatial region, for example, a cone-shaped region. Figure 3 As shown, for LEO#1, which needs to avoid GSO satellites, the avoidance area is area #1; for LEO#2, which needs to avoid GSO satellites, the avoidance area is area #2.

[0124] For low-Earth orbit satellites, when the terminal equipment they serve is about to enter the avoidance zone, a handover command can be sent to the terminal equipment to instruct it to switch to a neighboring cell, thus avoiding a decrease in user experience due to the terminal equipment being unable to transmit data in the avoidance zone.

[0125] However, for a single low-Earth orbit (LEO) satellite, only the avoidance zone it needs to avoid (i.e., the avoidance zone determined based on the line connecting the LEO satellite and the high-Earth orbit (HEO) satellite) is known. Therefore, when a terminal device triggers a handover based on a distance event or a handover command from its serving satellite, such as... Figure 4As shown in (a), the terminal device may be located (or moved) within the target satellite's avoidance area; in this case, it can also be considered that the terminal device has fallen into the target satellite's avoidance area. Or, as... Figure 4 As shown in (b), the terminal device may not be within the avoidance zone of the target satellite, but is about to enter it. This means that even if the terminal device switches to the target cell, it will be unable to transmit data, resulting in a degraded user experience.

[0126] Based on this, embodiments of this application provide a communication method. When a terminal device (such as a first terminal device) meets the handover conditions, its source network device (i.e., the first network device) can send a handover request to a candidate target network device (such as a second network device). The candidate network device can choose whether to agree to the handover based on its own circumstances. For example, the candidate target network device can determine whether the terminal device is located in its avoidance zone (where communication is prohibited) or whether it is about to enter the avoidance zone. If so, it can reject the handover request. This avoids the terminal device being unable to transmit data after handover to the candidate target network device, thus preventing a decline in user experience. Furthermore, the terminal device can choose to handover to other candidate target network devices to ensure data transmission and improve user experience.

[0127] The technical solution provided in this application can be used in various communication systems, including satellite communication systems, high altitude platform station (HAPS) communication, UAV and other NTN systems, such as integrated communication and navigation (ICAN) systems, global navigation satellite systems (GNSS), and ultra-dense low-Earth orbit satellite communication systems. Satellite communication systems can be integrated with traditional mobile communication systems. For example, the mobile communication system can be a cellular system related to the 3rd generation partnership project (3GPP), such as the 4th generation (4G) long term evolution (LTE) system, the worldwide interoperability for microwave access (WiMAX) communication system, the evolved LTE system (LTE-Advanced, LTE-A) system, the 5G NR system, the vehicle to everything (V2X) system, the LTE and NR hybrid networking system, or the device-to-device (D2D) system, the machine-to-machine (M2M) communication system, the Internet of Things (IoT), and other future communication systems.

[0128] Alternatively, the communication system may be a non-3GPP communication system, such as an open radioaccess network (O-RAN or ORAN), a cloud radio access network (CRAN), or a communication system that integrates multiple of the above communication systems. This application does not impose any restrictions.

[0129] Figure 5 This is a schematic diagram of the architecture of the communication system used in the embodiments of this application. Figure 5 A schematic diagram of a possible, non-limiting system architecture is shown. (e.g.) Figure 5 As shown, the communication system 10 includes a RAN 100 and a core network (CN) 200. The RAN 100 includes at least one RAN node (e.g., Figure 5 110a and 110b (collectively referred to as 110) and at least one terminal device (such as Figure 5 RAN 100, denoted as RAN 120a-120j, is collectively referred to as RAN 120. RAN 100 may also include other RAN nodes, such as wireless relay devices or wireless backhaul devices. Figure 5 At least one of the following (not shown in the image). Terminal device 120 is wirelessly connected to RAN node 110. RAN node 110 is wirelessly or wired connected to core network 200. The core network equipment in core network 200 and RAN node 110 in RAN 100 can be different physical devices, or they can be the same physical device integrating core network logical functions and radio access network logical functions.

[0130] RAN 100 can be a 3GPP-related cellular system, such as a 4G, 5G mobile communication system, an NTN system, or a future-oriented evolution system. RAN 100 can also be an open access network (open RAN, O-RAN or ORAN), CRAN, or a wireless fidelity (Wi-Fi) system. RAN 100 can also be a communication system that integrates two or more of the above systems.

[0131] The above Figure 5 The terminal equipment shown can be a device or module that accesses the aforementioned communication system and has corresponding communication functions. Terminal equipment can also be called user equipment (UE), mobile station, mobile terminal, etc. Terminal equipment 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 grids, smart furniture, smart offices, smart wearables, smart transportation, smart cities, etc. Terminal equipment can be mobile phones, tablets, computers with wireless transceiver capabilities, wearable devices, vehicles, drones, helicopters, airplanes, ships, robots, robotic arms, smart home devices, transportation vehicles with wireless communication capabilities, communication modules, etc. The embodiments of this application do not limit the form of the terminal equipment. Terminal equipment typically contains communication modules, circuits, or chips that perform corresponding communication functions. Terminal equipment can also be configured with program instructions for performing corresponding communication functions.

[0132] The above Figure 5The RAN node 110 shown, sometimes also referred to as access network equipment, RAN entity, or access node, constitutes part of the communication system and assists terminal equipment in achieving wireless access. Multiple RAN nodes 110 in the communication system 10 can be of the same type or different types. In some scenarios, the roles of RAN node 110 and terminal equipment 120 are relative, for example... Figure 5 Network element 120i can be a helicopter or a drone, and it can be configured as a mobile base station. For terminal devices 120j that access RAN 100 through network element 120i, network element 120i is a base station; however, for base station 110a, network element 120i is a terminal device. RAN node 110 and terminal device 120 are sometimes referred to as communication devices, for example... Figure 5 Network elements 110a and 110b can be understood as communication devices with base station functions, while network elements 120a-120j can be understood as communication devices with terminal equipment functions.

[0133] In one possible scenario, a RAN node can be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next-generation NodeB (gNB), a base station in a future mobile communication system, or an access node in a WiFi system, etc. Figure 5 110a), micro base stations or indoor stations (such as Figure 5 The RAN node can be a relay node or donor node (as described in section 110b), or a wireless controller in a CRAN scenario. Optionally, the RAN node can also be a server, wearable device, vehicle, or in-vehicle equipment. For example, in vehicle-to-everything (V2X) technology, the RAN node can be a roadside unit (RSU). All or part of the functions of the RAN node in this application can also be implemented through software functions running on hardware, or through virtualization functions instantiated on a platform (e.g., a cloud platform). The RAN node can also be equipped with communication modules, circuits, or chips that perform corresponding communication functions. The RAN node can also be configured with program instructions for performing corresponding communication functions and corresponding program instructions. The RAN node in this application can also be a logical node, logical module, or software capable of implementing all or part of the RAN node functions.

[0134] In another possible scenario, multiple RAN nodes collaborate to assist terminal devices in achieving wireless access, with different RAN nodes each implementing a portion of the base station's functions. For example, RAN nodes can be central units (CUs), distributed units (DUs), CU-control plane (CPs), CU-user plane (UPs), or radio units (RUs), etc. CUs and DUs can be set up separately or included in the same network element, such as a baseband unit (BBU). RUs can be included in radio frequency equipment or radio frequency units, such as remote radio units (RRUs), active antenna units (AAUs), or remote radio heads (RRHs).

[0135] In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meaning. For example, in an ORAN system, CU can also be called O-CU (open CU), DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. For ease of description, this application uses CU, CU-CP, CU-UP, DU, and RU as examples. Any of the units among CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented through software modules, hardware modules, or a combination of software and hardware modules.

[0136] In some embodiments, the CU and DU can be divided according to the protocol layer of the wireless network: for example, the functions of the Packet Data Convergence Protocol (PDCP) layer and above (such as the Radio Resource Control (RRC) layer and the Service Data Adaptation Protocol (SDAP) layer) are set in the CU, and the functions of the protocol layers below the PDCP layer (such as the Radio Link Control (RLC) layer, the Media Access Control (MAC) layer, or the Physical (PHY) layer) are set in the DU; or, for example, the functions of the protocol layers above the PDCP layer are set in the CU, and the functions of the protocol layers below the PDCP layer are set in the DU, without restriction.

[0137] See Figure 6 In (a), the functional settings of CU and DU in the embodiments of this application are shown. Figure 6 In (a) of the diagram, the RAN node consists of a CU-CP, a CU-UP, and a DU. The CU-CP implements the functions of the RRC layer and the control plane functions of the PDCP layer. The CU-UP implements the functions of the SDAP layer and the user plane functions of the PDCP layer. The DU implements the functions of the RLC layer, the MAC layer, and the PHY layer. The CU-CP and CU-UP are connected via an E1 interface, the CU-CP and DU are connected via an F1-C interface, and the CU-UP and DU are connected via an F1-U interface.

[0138] See Figure 6 In (b), the functional settings of CU and DU in the embodiments of this application are shown. Figure 6 In (b) of the diagram, the RAN node consists of a CU and two DUs. The CU implements the functions of the RRC layer, SDAP layer, and PDCP layer, while the DUs implement the functions of the RLC layer, MAC layer, and PHY layer. The CU and DUs are connected via an F1 interface.

[0139] The above division of CU and DU processing functions according to protocol layers is merely an example; other methods can also be used. For instance, CUs or DUs can be divided into those with more protocol layer functions, or they can be divided into those with partial protocol layer processing functions. For example, some functions of the RLC layer and the protocol layer functions above the RLC layer can be placed in the CU, while the remaining functions of the RLC layer and the protocol layer functions below the RLC layer can be placed in the DU. Furthermore, the functions of CUs or DUs can be divided according to service type or other system requirements, such as by latency. Functions that need to meet latency requirements can be placed in the DU, while functions that do not need to meet this latency requirement can be placed in the CU.

[0140] In some embodiments, the RU may be included in a radio frequency device or radio frequency unit, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH).

[0141] In some embodiments, when the RAN node is an access network device or a module of an access network device in an open ORAN system, in the ORAN system, CU can also be called open (O)-CU, DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. Any of the units among CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0142] For example, the network elements and their functions included in the ORAN system can be shown in Table 1 below:

[0143] Table 1

[0144]

[0145]

[0146] Figure 7 A schematic diagram of an O-RAN communication system architecture is shown. Figure 7 As shown, the O-RAN system includes a non-real-time RAN intelligent controller (Non-RT RIC), a near-real-time RAN intelligent controller (Near-RT RIC), an O-eNB, an O-CU-CP, an O-CU-UP, an O-DU, an O-RU, and an O-RAN Cloud (O-cloud).

[0147] The Non-RT RIC is used for non-real-time intelligent management of RAN functions. It enables artificial intelligence (AI) / machine learning (ML) workflows, including model training and updates, and guides applications / functions within the Near-RT RIC based on policies. The Non-RT RIC resides within the Service Management and Orchestration framework (SMO) module. The Near-RT RIC is used for near real-time intelligent management of the RAN. Through data collection and related operations on the E2 interface, it achieves near real-time control and optimization of O-RAN modules and resources. The O-CU implements the RRC, PDCP, and SDAP layers and other control functions in the 3GPP standard. The O-CU-CP, similar to the CU-CP in the NR system, implements the functions of the RRC layer and the control plane functions of the PDCP layer. It is part of the O-CU. The O-CU-UP, similar to the CU-UP in the NR system, implements the functions of the SDAP layer and the user plane functions of the PDCP layer. It is part of the O-CU.

[0148] O-DU is based on low-layer function segmentation and is used to implement the RLC layer, MAC layer, and higher physical layer (Higher PHY) functions in the 3GPP standard. The higher physical layer functions include one or more of the following: forward error correction (FEC) encoding / decoding, scrambling / descrambling, or modulation / demodulation. O-RU is also based on low-layer function segmentation and is used to implement the lower physical layer (Lower PHY) functions and radio frequency (RF) functions in the 3GPP standard. The lower physical layer functions include one or more of the following: fast fourier transform (FFT) / inverse fast fourier transform (iFFT), digital beamforming, or physical random access channel (PRACH) extraction and filtering. Similar to TRP or RRH in 3GPP, but it includes lower physical layer functions such as FFT / iFFT or PRACH extraction. O-Cloud, as a cloud computing platform, includes physical infrastructure nodes for hosting O-RAN functions such as RAN intelligent controllers (RICs) and O-DUs; it also supports software components (such as operating systems, virtual machine monitoring, and container runtimes), management, and orchestration functions.

[0149] also, Figure 7 The A1 interface serves as the communication interface between the Non-RT RIC and the Near-RT RIC, used for intelligent and dynamic control of radio resources within the O-RAN. The Non-RT RIC provides policies, rich information, and ML model updates to the Near-RT RIC via the A1 interface, while the Near-RT RIC provides policy feedback to the Non-RT RIC via the A1 interface. The E2 interface is an open interface between two endpoints, used to connect the Near-RT RIC and the RAN node. The RAN node can include: CU and DU in 5G, O-RAN compatible eNB in ​​4G, O-CU in O-RAN (such as at least one of O-CU-CP or O-CU-UP), or at least one of O-DU, etc. The RIC can obtain RAN node data collection and feedback through the E2 interface, and the RAN node can obtain control feedback from the Near-RT RIC through the E2 interface. The O1 interface is used between the management entity in the SMO and the O-RAN module (such as...). Figure 7The O2 interface is the interface between the SMO and the RAN module; it is used for operation management, and through this interface, error, configuration, accounting, performance and security (FCAPS) management, software management, and file management are implemented. The O2 interface is the interface between the SMO and the infrastructure management framework that supports O-RAN virtual network functions (such as...). Figure 7 The interfaces between cloud infrastructure modules (CU-CP and CU-UP). The E1 interface is the interface between CU-CP and DU. The F1-C interface is the interface between CU-CP and DU. The F1-U interface is the interface between CU-UP and DU.

[0150] In the O-RAN architecture, a network element with positioning capabilities may be a real-time RAN intelligent controller (RT RIC). The O-DU performs multipath measurement and reports the measurement results to the RT RIC. A network element with positioning capabilities may also be an O-CU. The O-CU receives the multipath measurement results reported by the O-DU and performs position calculation.

[0151] In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meaning. For example, in an ORAN system, CU can also be called O-CU (open CU), DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. For ease of description, this application uses CU, CU-CP, CU-UP, DU, and RU as examples.

[0152] This application uses the NTN system as an example, namely the one described above. Figures 5-7 The communication system described in any of these examples is an NTN system. In this NTN system, the RAN nodes (such as base stations) operate in two modes: transparent transmission mode and regenerative mode. The communication system also includes non-terrestrial platforms, such as low-altitude platforms (e.g., drones), high-altitude platforms (e.g., aircraft), or satellites. For ease of description, the following example uses a satellite as an example; this will be discussed further without further elaboration. The satellite can communicate with the base station through an NTN gateway (or gateway station), meaning the communication system also includes an NTN gateway. Typically, the NTN gateway is deployed on the ground. The link between the satellite and the NTN gateway can be called a feeder link.

[0153] Taking the RAN node as a base station as an example, such as Figure 8As shown in (a) above, this is one possible implementation of a communication system based on transparent transmission mode. Figure 8 In (a) of the diagram, the satellite acts as a wireless relay node (or, in other words, the satellite has relay forwarding capabilities). In this case, the satellite can perform operations such as radio frequency filtering, frequency conversion, and amplification. That is, the satellite primarily acts as a Layer 1 (L1) relay, regenerating physical layer signals, and does not involve other higher protocol layers. Furthermore, in... Figure 8 In (a) of the above, the NTN gateway has some or all of the functions of a base station. In this case, the NTN gateway can act as a base station, or the NTN gateway and the base station can be deployed separately. NG-RAN has... Figure 8 The functions of satellite, NTN gateway, and base station in (a) mean that satellite, NTN gateway, and base station can be merged into NG-RAN.

[0154] like Figure 8 As shown in (b) above, this is one possible implementation of a communication system based on regeneration mode. Figure 8 In (b) of this example, the satellite can perform some or all of the functions of a base station; that is, the satellite has data processing capabilities. In other words, the satellite can be used as a base station. In this case, the NTN gateway and the satellite can transmit user plane data of the terminal equipment through the satellite radio interface (SRI). NG-RAN has... Figure 8 The functions of the base station and NTN gateway in (b) of the document, that is, Figure 8 The base station and NTN gateway in (b) can be merged into NG-RAN.

[0155] Furthermore, in cases where satellites can perform some or all of the functions of a base station, such as... Figure 8 As shown in (c), there is an ISL between different satellites, and satellites can communicate with each other via ISL. NG-RAN has... Figure 8 The functionality of multiple base stations and multiple NTN gateways in (c) means that... Figure 8 Multiple base stations and multiple NTN gateways in (c) can be merged into NG-RAN.

[0156] Or, such as Figure 8 As shown in (d), the satellite can have the DU processing function of a base station, or in other words, the satellite can act as a DU. In this scenario, the CU processing function of the base station can be deployed on the ground, and the CU and DU communicate via the F1 interface through the NTN gateway. NG-RAN has... Figure 8 The functions of DU, NTN gateway, and CU in (d) of the document, that is, Figure 8 In (d), the DU, NTN gateway, and CU can be merged into NG-RAN.

[0157] exist Figure 8 (like Figure 8 (a) in Figure 8 In the architecture shown in (d)), NG refers to the interface between the base station and the core network. Uu refers to the interface between the base station and the terminal equipment. Xn refers to the interface between base stations. It is understood that as the communication system evolves, the interface names between the base station and the core network, the interface names between the base station and the terminal equipment, and the interface names between base stations may also change, and this application does not specifically limit them.

[0158] Optionally, when a satellite acts as a wireless relay node with relay forwarding capabilities, it can be considered to be operating in transparent mode. When a satellite has data processing capabilities and can perform some or all of the functions of a base station, it can be considered to be operating in regenerative mode. For a given satellite, it may support only transparent mode, only regenerative mode, or both transparent and regenerative modes, and it may be able to switch between transparent and regenerative modes.

[0159] The communication method and apparatus provided in this application will be further described below with reference to the accompanying drawings. It is understood that this application uses a first communication device and a second communication device as examples to illustrate the interaction. Both the first communication device and the second communication device are... Figure 8 The satellite or NG-RAN node (also referred to as a network device) in the communication system shown in any one of (a) to (d) of this application. Furthermore, the communication system described in this application also includes a third communication device. This third communication device can be... Figure 8 Any terminal device in the communication system shown in any of (a) to (d) of the third communication device is the first communication device.

[0160] This application does not limit the execution entity of the interactive illustration. For example, the method executed by the NG-RAN node in this application can also be implemented by a module applied to the NG-RAN node (e.g., a circuit, chip, or chip system), or a logic node, logic module, or software that can implement all or part of the functions of the NG-RAN node. Alternatively, it can be implemented by at least one module in the communication or computing of the NG-RAN node, or a circuit or chip in the NG-RAN node responsible for at least one function in communication or computing (e.g., a modem chip (also known as a baseband chip), or a system-on-a-chip (SoC) chip / system-in-a-package (SIP) chip containing a modem core, or a graphics processing unit (GPU) / AI processor / application-specific integrated circuit (ASIC)). Similarly, the method executed by the terminal device in this application can also be implemented by at least one module applied to the communication or computing of the terminal device, or a circuit or chip in the terminal device responsible for at least one function in communication or computing (e.g., a modem chip (also known as a baseband chip), or a SoC chip / SIP chip containing a modem core, or a GPU / AI processor / ASIC).

[0161] See Figure 9 The diagram illustrates a flowchart of a communication method provided in an embodiment of this application. Figure 9 As shown, taking the first communication device as the first network device, the second communication device as the second network device, and the third communication device as the first terminal device as an example, that is, taking the interaction between the first network device, the second network device, and the first terminal device as an example, the method may include:

[0162] S901, the first network device sends a first message to the second network device; correspondingly, the second network device receives the first message from the first network device. The first message requests a switch from the first terminal device to the second network device. The first network device is the serving network device of the first terminal device, also known as the source network device. The second network device is a candidate target network device for the first terminal device. Reasons for refusing a switch include: the first terminal device is located within a first area; or, the first terminal device will move to the first area within a first time period; or the second network device is prohibited from communication within the first area.

[0163] For example, since the first message is used to request the first terminal device to switch to the second network device, that is, the first message is a switching request sent by the serving network device (i.e. the first network device) of the first terminal device to the candidate target network device (i.e. the second network device), the candidate target network device can know from the first message that the first terminal device expects to switch to the candidate target network device.

[0164] Understandably, network devices can establish one or more cells. Terminal devices typically connect to one of these cells, which becomes the serving cell. The network device to which the serving cell belongs is called the serving network device. In scenarios where the terminal device performs cell handover, the serving cell can also be called the source cell, and the serving network device can also be called the source network device.

[0165] Furthermore, when a terminal device undergoes a handover, its serving cell typically sends a handover request to a candidate target cell. The network device to which this candidate target cell belongs is referred to as the terminal device's candidate target network device. In other words, in step S901, when the first network device sends a first message to the second network device, it is actually the first terminal device's serving cell sending a first message to the first terminal device's candidate target cell. Here, the first terminal device's serving cell is one of one or more cells established by the first network device, and the first terminal device's candidate target cell is one of one or more cells established by the second network device.

[0166] Optionally, the first message can be a handover request message.

[0167] Optionally, if the first network device meets the handover conditions, the first network device sends a first message to the second network device.

[0168] As an example, the handover condition being met by the first terminal device can be understood as follows: the measurement result of the first terminal device meets the event that triggers the reporting of a measurement report. The measurement report contains the measurement result of the first terminal device. In other words, the handover condition is the event that triggers the reporting of a measurement report.

[0169] Optionally, in this example, the first network device may send measurement configuration information to the first terminal device, enabling the first terminal device to perform measurements (such as measurements on the second network device) according to the measurement configuration information and obtain measurement results; and when the measurement results satisfy the event indicated by the measurement configuration information (triggering the reporting of a measurement report), it shall report a measurement report containing the measurement results.

[0170] For example, the process by which the first terminal device receives measurement configuration information, performs the measurement, and reports a measurement report containing the measurement results can be found in the above description. Figure 1 The relevant descriptions of steps S101 to S103 will not be repeated here.

[0171] Optionally, the events indicated by the measurement configuration information may include distance events and / or signal quality events. For example, the first terminal device may perform corresponding operations based on the events indicated by the measurement configuration information.

[0172] For example, for distance events, the first terminal device can perform corresponding location sensing operations to obtain the location of the measurement object (such as the second network device); the first terminal device can obtain the location of the measurement object from the first network device. Then, it can determine the distance between the measurement object and the first terminal device. For signal quality events, the first terminal device can perform corresponding signal quality measurement operations (i.e., measure the signal quality of the measurement object within the measurement gap, where the measurement configuration information also indicates the measurement gap), thereby determining the signal quality of the measurement object.

[0173] Specifically, the process by which the first terminal device performs corresponding measurements based on the events indicated by the measurement configuration information can be found in the above description. Figure 1 The relevant descriptions in step S102 are not repeated here.

[0174] Optionally, the measurement report may also indicate at least one candidate target network device for which the measurement result satisfies the event indicated by the measurement configuration information. For example, the measurement report may also indicate a candidate set of target network devices, which includes at least one candidate target network device.

[0175] For example, the measurement report includes a list of triggering cells. This list contains at least one cell ID, and the measurement results of all cells in this list satisfy the event. At least one candidate target network device controls at least one cell indicated in the triggering cell list (i.e., the cell represented by at least one cell ID).

[0176] Specifically, when the first terminal device determines that the measurement result of a certain measurement object meets the event indicated by the measurement configuration information, it can add the cell ID corresponding to the measurement result to the trigger cell list.

[0177] Optionally, the second network device is the highest-priority target network device among at least one candidate target network device. The priority of the at least one candidate target network device is related to the event indicated by the measurement configuration information.

[0178] For example, when the event indicated by the measurement configuration information is a distance event, the priority of at least one candidate target network device can be ranked according to the distance between it and the first terminal device. For example, the second network device is the target network device that is closest to the first network device among the at least one candidate target network device. When the event indicated by the measurement configuration information is a signal quality event, the priority of at least one candidate target network device can be ranked according to the magnitude of its signal quality. For example, the second network device is the target network device with the strongest signal quality among the at least one candidate target network device.

[0179] As another example, the handover condition being met by the first terminal device can be understood as the location of the first terminal device meeting the handover conditions. These handover conditions include the first terminal device about to enter the avoidance zone of the first network device.

[0180] For example, the first network device can monitor the location of the first terminal device based on its mobility, and determine that the first terminal device meets the handover conditions when it is about to enter the avoidance area of ​​the first network device.

[0181] For example, if the first terminal device moves into the avoidance area of ​​the first network device during time period #1, it can be assumed that the first terminal device is about to enter the avoidance area of ​​the first network device. In this case, the handover condition can also be considered to include the first terminal device moving into the avoidance area of ​​the first network device during time period #1. Here, time period #1 is a preset value, and the start time of time period #1 is the time when the first network device monitors the first terminal device.

[0182] For example, time period #1 may be predefined by a protocol, or it may be determined by the first terminal device and communicated to the first network device, or it may be predetermined by the first network device; this application does not impose any restrictions.

[0183] For example, the implementation of the avoidance zone of the first network device can be found in the relevant descriptions in the above-mentioned related technologies, and will not be repeated here.

[0184] Optionally, in this example, the first terminal device is located within the signal coverage area of ​​the second network device.

[0185] For example, the first terminal device may be located within the signal coverage area of ​​multiple network devices, and the second network device may be one of the multiple network devices. For instance, the second network device may be any one of the multiple network devices; or, the second network device may be the network device closest to the first terminal device among the multiple network devices; or, the second network device may be the network device with the strongest signal quality among the multiple network devices.

[0186] Specifically, the implementation of the distance between the multiple network devices and the first terminal device, as well as the signal quality of the multiple network devices, is similar to the implementation of the relevant steps in the above "as an example" section. For details, please refer to the relevant description in the above "as an example" section, which will not be repeated here.

[0187] S902, the second network device sends a second message to the first network device; correspondingly, the first network device receives the second message from the second network device. The second message indicates a handover refusal and includes information indicating the reason for the handover refusal.

[0188] For example, similar to the implementation of step S901 above, the second network device sends a second message to the first network device. In fact, the candidate target cell of the first terminal device sends a second message to the serving cell of the first terminal device.

[0189] Optionally, the second message is either a handover reject message or a handover preparation failure message.

[0190] Optionally, the indication of the reason for refusing to switch is the Cause field in the second message.

[0191] Optionally, after receiving the first message, the second network device can determine whether to allow the first terminal device to access the network (i.e., whether to allow the first terminal device to switch from the first network device to the second network device, or in other words, whether to allow the first terminal device's switch request (i.e., the first message)). It then sends its determination result back to the first network device. Furthermore, it can also provide the reason for obtaining this determination result.

[0192] Optionally, the first area is a avoidance area for the second network device.

[0193] For example, the second network device can determine whether to allow the first terminal device to access the network based on its own circumstances. It is understood that, based on the aforementioned related technologies, network devices prohibit communication within their avoidance zones; and, when a terminal device is about to enter this avoidance zone, in order to ensure normal communication, the network device can switch the terminal device to another network device. Therefore, to ensure normal communication for the first terminal device, the second network device can determine whether to allow the first terminal device to access the network based on the relationship between its avoidance zone and the location of the terminal device. Specifically, if the first terminal device switches to the second network device when it is located within the first zone, or when it is about to enter the first zone, normal communication for the first terminal device cannot be guaranteed. Therefore, in this situation (i.e., the first terminal device is located within the avoidance zone of the second network device, or the second terminal device is about to enter the avoidance zone of the second network device), access for the first terminal device can be denied; that is, the determination result is a rejection of the first terminal device's switching request (or a rejection of the switching). Furthermore, the reason for the rejection is that the first terminal device is located within the avoidance zone of the second network device, or the first terminal device is about to enter the avoidance zone of the second network device.

[0194] For example, when the first terminal device is located within the first area, the reason for refusing handover includes the fact that the first terminal device is located within the first area. When the first terminal device is not located within the first area, the second network device can determine whether the first terminal device is about to enter the first area by determining whether the first terminal device will move into the first area within a first time period.

[0195] For example, if the first terminal device will move to the first area within the first time period, it means that the first terminal device is about to enter the first area. In this case, the reason for refusing handover includes either the first terminal device being about to enter the first area, or the first terminal device moving to the first area within the first time period. If the first terminal device will not move to the first area within the first time period, it means that the first terminal device is not about to enter the first area.

[0196] Specifically, the first time period can be predefined; for example, it can be predefined through a protocol, or it can be determined by the first terminal device and informed to the second network device, or it can be predefined by the second network device; in addition, the first time period and time period #1 can be the same or different, and this application does not limit them.

[0197] Optionally, the location of the first terminal device can be provided to the second network device by the first network device, or it can be obtained by the second network device from the core network device.

[0198] For example, the first network device can directly send signaling to the second network device to inform the second network device of the location of the first terminal device. Alternatively, the first network device can send the location of the first terminal device to the core network device; then, the core network device can proactively inform the second network device of the location of the first terminal device, or the second network device can query the location of the first terminal device from the core network device.

[0199] For ease of description, the following example will be used, where the location of the first terminal device is communicated to the second network device by the first network device. This will be explained uniformly here and will not be repeated.

[0200] In one possible implementation, the first network device can send signaling to the second network device separately to inform it of the location information of the first terminal device.

[0201] For example, taking the first network device informing the second network device of the location information of the first terminal device through a fourth message (the implementation of the third message can be found in the relevant description in the following embodiments, and will not be repeated here), as an example, Figure 9 As shown, prior to step S901, the communication method further includes step S900:

[0202] S900, the first network device sends a fourth message to the second network device; correspondingly, the second network device receives the fourth message from the first network device. The fourth message is used to indicate the location information of the first terminal device.

[0203] As an example, the location information of the first terminal device may include the latitude and longitude information of the first terminal device. That is, the fourth message contains the latitude and longitude information of the first terminal device.

[0204] It is understood that a clearance zone typically includes at least one beam position, and for a beam position in a non-clearance zone adjacent to that beam position, it can be assumed that a terminal device within the coverage area of ​​that beam position is about to enter the clearance zone. For example, such as Figure 10 As shown, network devices include wavelets #0 to #7. If wavelets #0 to #2 all belong to the avoidance zone (i.e., at least one wavelet includes wavelets #0 to #2), it means that terminal devices within the coverage area of ​​wavelet #3 are about to enter the avoidance zone. For low-Earth orbit satellites, due to their mobility, the wavelets corresponding to the avoidance zone of the low-Earth orbit satellite change at different times.

[0205] Therefore, the second network device can determine which of the multiple wavelengths of the first terminal device it is based on the location information of the first terminal device. If the first terminal device is within the coverage area of ​​the wavelengths included in the first region (such as any one of the at least one wavelengths), then it is determined that the first terminal device is located in the first region; if the first terminal device is within the coverage area of ​​an adjacent wavelength included in the first region, then it is determined that the first terminal device is about to enter the first region.

[0206] As another example, based on the relationship between the avoidance area and the wave position mentioned above, the first network device can also indirectly indicate the position of the first terminal device by indicating the information of the wave position in multiple wave positions of the second network device.

[0207] Taking an example where a wave position in the second network device includes a first wave position, and the first terminal device is located within the coverage area of ​​the first wave position, the fourth message can include information about the first wave position (e.g., the ID of the first wave position). Therefore, the second network device can directly determine which of its multiple wave positions the first wave position belongs to. If the first wave position is a wave position included in the first region (e.g., any one of at least one wave position), then the first terminal device is determined to be located within the first region; if the first wave position is an adjacent wave position to a wave position included in the first region, then the first terminal device is determined to be about to enter the first region.

[0208] In one possible implementation, the fourth message and the first message are the same message. That is, the first message also includes the location information of the first terminal device, or in other words, the location information of the first terminal device is carried in the first message. In this case, steps S900 and S901 are combined into one step. Thus, the second network device can determine the second message based on the location information of the first terminal device.

[0209] For example, the implementation of the location information of the first terminal device and the implementation of the second network device determining the second message based on the location information of the first terminal device can be found in the relevant descriptions in the two examples above, and will not be repeated here.

[0210] Optionally, when the second network device determines that a handover is refused, it can determine the reason for the handover refusal from among the multiple reasons for handover refusal included in the first correspondence. That is, the first correspondence includes multiple reasons for handover refusal, such as: the terminal device is located within the avoidance area of ​​the candidate target network device, or the terminal device is about to enter the avoidance area of ​​the candidate target network device. For example, the first correspondence can be a list of reasons for handover refusal.

[0211] Optionally, the first correspondence may include a correspondence between multiple cause values ​​and multiple reasons for refusing handover. Each cause value corresponds one-to-one with a different reason for refusing handover.

[0212] Optionally, the indication information for the reason for the handover refusal includes a first reason value, which is the reason value corresponding to the reason for the current handover refusal among the multiple reasons for handover refusal in the first correspondence.

[0213] For example, the first correspondence can be represented in the form of a table or a set; for instance, when represented in the form of a table, the first correspondence can include the content shown in Table 2:

[0214] Table 2

[0215] Cause value Reasons for refusing to switch 0 Reason #0 1 Reason #2 2 Reason #3 … …

[0216] When represented as a set, the first correspondence can include: {0; reason #0}, {1; reason #1}, {2; reason #2}, etc. Here, reason #0 can be that the terminal device is located within the avoidance area of ​​the candidate target network device, and reason #1 can be that the terminal device is about to enter the avoidance area of ​​the candidate target network device. Therefore, if the reason for the handover refusal is that the first terminal device is located within the first area, the first reason value is 0; if the reason for the handover refusal is that the first terminal device is about to enter the first area, the first reason value is 1.

[0217] Furthermore, in the first correspondence, the multiple reasons for refusing handover can belong to different cause groups; that is, the multiple reasons for refusing handover in the first correspondence can be divided into multiple cause groups. Each cause group contains some of the multiple reasons for refusing handover, resulting in multiple cause groups containing multiple reasons for refusing handover. In other words, the first correspondence can contain multiple cause groups, where the multiple reasons for refusing handover contained in each cause group correspond to different cause values.

[0218] At this time, the indication information for the reason for the handover refusal also includes a first group value. The first group value is the group value corresponding to the branch office to which the reason for this handover refusal belongs among multiple reason groups. The first correspondence also includes the correspondence between multiple group values ​​and multiple reason groups, as well as the correspondence between multiple reason groups and multiple reasons for handover refusal. Among them, multiple group values ​​correspond one-to-one with multiple reason groups.

[0219] For example, in this case, the first correspondence described in Table 2 can be replaced with the content shown in Table 3:

[0220] Table 3

[0221]

[0222] Specifically, if reason #0 in reason group #0 is that the terminal device is located within the avoidance area of ​​the candidate target network device, and reason #1 is that the terminal device is about to enter the avoidance area of ​​the candidate target network device, then the value of the first group is 0. Furthermore, if the reason for this handover refusal is that the first terminal device is located within the first area, the value of the first reason is 0; if the reason for this handover refusal is that the first terminal device is about to enter the first area, then the value of the first reason is 1.

[0223] Alternatively, if reason #0 in reason group #1 is that the terminal device is located within the avoidance area of ​​the candidate target network device, and reason #1 is that the terminal device is about to enter the avoidance area of ​​the candidate target network device, then the first group value is 1. Furthermore, if the reason for this handover refusal is that the first terminal device is located within the first area, the first reason value is 0; if the reason for this handover refusal is that the first terminal device is about to enter the first area, then the first reason value is 1.

[0224] It is understandable that the above introduction to the first correspondence relationship uses the example of the correspondence between multiple cause values ​​and multiple reasons for refusing to switch, and further, the correspondence between multiple group values ​​and multiple cause groups, to illustrate the implementation of the first correspondence relationship. In reality, cause values, group values, and other parameters are usually implicitly reflected in the first correspondence relationship. The following is a detailed introduction to the implementation of the first correspondence relationship when cause values, group values, and other parameters are implicitly reflected. For example, the first correspondence relationship can be implemented based on the following two scenarios:

[0225] Scenario 1: The first correspondence includes the correspondence between multiple reason values ​​and multiple reasons for refusing to switch.

[0226] For example, in Scenario 1, the reason value is implicitly reflected in the first correspondence, meaning the first correspondence displays multiple reasons for refusing to switch. In other words, Table 2 can be replaced with the content shown in Table 4:

[0227] Table 4

[0228] Reasons for refusing to switch Reason #0 Reason #2 Reason #3 …

[0229] At this point, in the first correspondence described in Table 4, the reason values ​​corresponding to the reasons for refusing to switch, from top to bottom, are 0, 1, 2, ...; that is, the reason value corresponding to reason #0 is 0, the reason value corresponding to reason #1 is 1, and the reason value corresponding to reason #2 is 2. In other words, in the first correspondence, the reason values ​​corresponding to the reasons for refusing to switch shown in the default list increase sequentially from top to bottom.

[0230] Scenario 2: The first correspondence includes the correspondence between multiple reason values ​​and multiple reasons for refusing handover, the correspondence between multiple group values ​​and multiple reason groups, and the correspondence between multiple reason groups and multiple reasons for refusing handover.

[0231] For example, in Scenario 2, the cause value and grouping value can be implicitly reflected in the first correspondence, that is, the first correspondence displays the correspondence between multiple cause groups and multiple reasons for refusing to switch. In other words, Table 3 can be replaced with the content shown in Table 5:

[0232] Table 5

[0233]

[0234] At this point, in the first correspondence described in Table 5, the group values ​​corresponding to the cause groups in the list, from top to bottom, are 0, 1, 2, ...; that is, the group value corresponding to cause group #0 is 0, and the group value corresponding to cause group #1 is 1. In other words, in the first correspondence, the default list shows cause groups from top to bottom with their corresponding group values ​​increasing sequentially.

[0235] Furthermore, in the first correspondence described in Table 5, in the reasons for resolute switching (i.e., the reasons for resolute switching within each reason group), from top to bottom, the reason values ​​corresponding to the reasons for refusing switching are 0, 1, 2, ...; within each reason group, the reason value corresponding to reason #0 is always 0, the reason value corresponding to reason #1 is always 1, and the reason value corresponding to reason #2 is always 2. That is to say, in the first correspondence, by default, the reasons for refusing switching shown in the list within each reason group from top to bottom correspond to reasons with progressively increasing reason values.

[0236] As an example, the reason group corresponding to the first group value can be the reason group defined in the current protocol. That is, two reasons for refusing handover can be added to a reason group in the reason group defined in the current protocol, namely reason #1: the terminal device is located in the avoidance area of ​​the candidate target network device, and reason #2: the terminal device is about to enter the avoidance area of ​​the candidate target network device.

[0237] For example, the cause groups defined in the current protocol include groups for handover refusal due to problems in the radio network layer (referred to as "radio network layer cause"), groups for handover refusal due to problems in the transport layer (referred to as "transport layer cause"), groups for handover refusal due to problems in the non-access-stratum (NAS) (referred to as "NAS cause"), groups for handover refusal due to problems in the protocol (referred to as "protocol cause"), and groups for handover refusal due to various other miscellaneous problems (referred to as "miscellaneous cause").

[0238] Specifically, taking the addition of the two reasons for refusing to switch (i.e., reason #1 and reason #2) to the "Other Reasons" group as an example, Table 5 can be replaced with the content shown in Table 6:

[0239] Table 6

[0240]

[0241]

[0242] That is, the reasons for refusing handover, expressed in bold font as shown in Table 6 above, can be added to the "Other Reasons" group, so that the first correspondence can include the content shown in Table 6 above. Thus, the first group value is the group value corresponding to the "Other Reasons" group (or, in other words, the first group value is used to indicate the "Other Reasons" group); furthermore, the first reason value can be the reason in the "Other Reasons" group: the reason value corresponding to the terminal device being located within the avoidance area of ​​the candidate target network device, or the first reason value can be the reason in the "Other Reasons" group: the reason value corresponding to the terminal device about to enter the avoidance area of ​​the candidate target network device. It should be noted that the avoidance reason indicated by the first reason value can also be included in the "Other Reasons" group in Table 6, and this application does not limit this.

[0243] As another example, the reason group corresponding to the first group value can be a newly defined reason group. For example, this newly defined reason group can be called the avoidance reason group. Thus, multiple reason groups in the first correspondence can include the avoidance reason group. Further, the avoidance reason group contains two reasons for refusing handover: reason #1: the terminal device is located in the avoidance area of ​​the candidate target network device, and reason #2: the terminal device is about to enter the avoidance area of ​​the candidate target network device. (That is, the avoidance reason group contains the reason for this handover refusal).

[0244] For example, the avoidance reason group can be a newly added reason group based on the reason groups defined in the current protocol. That is, in this example, multiple reason groups include the reason groups defined in the current protocol as well as the avoidance reason group. In this case, Table 5 can be replaced with the content shown in Table 7:

[0245] Table 7

[0246]

[0247] That is, based on the existing reason groups, the reason groups shown in bold in Table 7 above can be added, and then the reasons for refusing handover shown in bold in Table 7 above can be added to these reason groups, so that the first correspondence can include the content shown in Table 7 above. Thus, the first group value is the group value corresponding to the group of avoidance reasons (or, the first group value is used to indicate the group of avoidance reasons); furthermore, the first reason value can be the reason in the avoidance reason group: the reason value corresponding to the terminal device being located in the avoidance area of ​​the candidate target network device, or the reason in the avoidance reason group: the reason value corresponding to the terminal device about to enter the avoidance area of ​​the candidate target network device. It should be noted that the above-mentioned avoidance reasons indicated by the first reason value can also be included in other existing reason groups in Table 7, and this application does not limit this.

[0248] It should be noted that, in this application, the cause group to which the handover is refused due to a problem based on the avoidance area (i.e., the terminal device is located in the avoidance area of ​​the candidate target network device, or the terminal device is about to enter the avoidance area of ​​the candidate target network device) belongs is referred to as the "avoidance cause group"; in fact, the cause group to which this cause belongs may also have other names, such as cause group #1, communication failure group, etc., and this application does not limit it.

[0249] Combining the two examples above, optionally, the second message includes a first field and a second field. The first field indicates the grouping value, and the second field indicates the reason value. That is, the indication information of the reason for refusing the handover is carried in the first field and the second field; and the first grouping value is located in the first field, and the first reason value is located in the second field.

[0250] For example, the first field can be an id-cause field. The first field can be represented by 3 bits; 3 bits of 0 indicate a packet with a wireless network layer cause; 3 bits of 1 indicate a packet with a transport layer cause; 3 bits of 2 indicate a packet with a NAS cause; 3 bits of 3 indicate a packet with a protocol cause; 3 bits of 4 indicate a packet with another cause; and 3 bits of 5 indicate a packet with a fallback cause. Therefore, if the first correspondence is as shown in Table 6 above, the first packet value is 4; if the first correspondence is as shown in Table 7 above, the first packet value is 5.

[0251] For example, the second field is determined based on the value of the first field. Specifically, when the first field indicates a packet with a Radio Network layer cause, the second field is the Cause Radio Network field; when the first field indicates a packet with a Transport layer cause, the second field is the Cause Transport field; when the first field indicates a packet with a NAS cause, the second field is the Cause NAS field; when the first field indicates a packet with a Protocol cause, the second field is the Cause Protocol field; when the first field indicates a packet with other causes, the second field is the Cause Misc field; and when the first field indicates a packet with an obstacle avoidance cause, the second field is the Obstruction Cause field. Therefore, if the first packet value indicates a packet with other causes (i.e., the first field indicates a packet with other causes), the first cause value is carried in the Other Cause field, meaning the second field is the Other Cause field in this case; if the first packet value indicates a packet with an obstacle avoidance cause (i.e., the first field indicates a packet with an obstacle avoidance cause), the first cause value is carried in the Obstruction Cause field, meaning the second field is the Obstruction Cause field in this case.

[0252] It is understood that the avoidance reason field is merely an exemplary designation, and this field can be replaced with other designations, such as other reason update field, field #1, or any other possible designation; similarly, the above reason value can also be replaced with any possible designation such as index, value, reason number, reason sequence number, etc.; the grouping value can also be replaced with any possible designation such as grouping index, grouping value, grouping identifier, etc.; this application does not impose any restrictions.

[0253] Furthermore, this application describes the implementation of the first correspondence relationship by taking as an example that the cause group of the first correspondence relationship includes all cause groups among wireless network layer cause, transport layer cause, NAS cause, and protocol cause. In reality, the first correspondence relationship may include some cause groups among wireless network layer cause, transport layer cause, NAS cause, or protocol cause, or the first correspondence relationship may not include any cause group among wireless network layer cause, transport layer cause, NAS cause, or protocol cause. In this case, the first correspondence relationship described in this application can be obtained by deleting the corresponding cause groups in Table 6 or Table 7 above, which will not be elaborated further.

[0254] The communication method provided in this application embodiment allows a terminal device (such as a first terminal device) whose serving network device (i.e., the first network device) can send a handover request to a candidate target network device (such as a second network device) when the terminal device meets the handover conditions. The candidate network device can then choose whether to agree to the handover based on its own circumstances. For example, the candidate target network device can determine whether the terminal device is located in its avoidance zone (where communication is prohibited) or whether it is about to enter the avoidance zone. If so, it can reject the handover request. This avoids the terminal device being unable to transmit data after handover to the candidate target network device, thus preventing a decline in user experience. Furthermore, the terminal device can choose to handover to other candidate target network devices to ensure data transmission and improve user experience.

[0255] Optionally, after step S902, the first network device may determine that the first terminal device will not switch to the second network device.

[0256] As an example, the statement that the first terminal device does not switch to the second network device can be understood as: the first terminal device does not perform a handover.

[0257] For example, such as Figure 11 As shown in (a), after step S902, the first network device can also execute step S903:

[0258] S903. Based on the second message, the first network device determines that the first terminal device will not perform a handover.

[0259] For example, since the second message indicates that the handover request of the first terminal device is rejected, the first network device does not send a handover instruction to the first terminal device when it learns that the second network device has rejected the handover of the first terminal device, so that the first terminal device does not need to perform a handover.

[0260] As another example, the first terminal device not switching to the second network device can be understood as: the first network device considers switching the first terminal device to other candidate target network devices besides the second network device, such as the third network device.

[0261] For example, as described above, when the first terminal device meets the handover conditions, the first terminal device can report a measurement report. This measurement report can indicate a candidate set of target network devices, which includes at least one candidate target network device. Both the second and third network devices are located within this candidate set. Therefore, the first network device can determine the third network device from the candidate set. The third network device can be any network device in the candidate set other than the second network device, or it can be the network device with the highest priority among the network devices in the candidate set other than the second network device (such as the network device with the strongest signal quality or the network device closest to the first terminal device).

[0262] Alternatively, when the handover condition for the first terminal device is that the first terminal device is about to enter the avoidance zone of the first network device, based on the foregoing, the second network device is one of a plurality of network devices within the coverage area that includes the location of the first terminal device. Therefore, the third network device can be any one of the plurality of network devices other than the second network device, or it can be the network device with the highest priority among the plurality of network devices other than the second network device (such as the network device with the strongest signal quality or the network device closest to the first terminal device).

[0263] For example, such as Figure 11 As shown in (b) above, after step S902, the communication method may further include the following steps:

[0264] S904, the first network device sends a third message to the third network device; correspondingly, the third network device receives the third message from the first network device. The third message is used to request that the first terminal device be switched to the third network device.

[0265] For example, the implementation of the third network device is similar to that of the second network device, that is, the cell established by the third network device includes the candidate target cell of the first terminal device. Thus, in step S904, the first network device sends a third message to the third network device, which is actually the serving cell of the first terminal device sending a third message to the candidate target cell.

[0266] Optionally, the third message can be a handover request message, or in other words, the third message can be carried within the handover request message. Specifically, the implementation of the third message is similar to that of the first message in step S901 above; please refer to the relevant description of the first message for details, which will not be repeated here.

[0267] S905, the third network device sends a response message of the third message to the first network device; correspondingly, the first network device receives the response message of the third message from the third network device.

[0268] For example, similar to step S905, the response message of the third network device sending the third message to the first network device is actually the response message of the candidate target cell sending the third message to the serving cell of the first terminal device.

[0269] For example, the third network device can determine whether the first terminal device is located in the third network device's avoidance zone or is about to enter the third network device's avoidance zone based on the location of the first terminal device, and then determine whether to allow the first terminal device to access.

[0270] If the first terminal device is not within the avoidance area of ​​the third network device, and the first terminal device is not about to enter the avoidance area of ​​the third network device, the third network device can perform access control and then send a response message of the third message to the first network device. The response message of the third message indicates that handover is permitted (i.e., access of the first terminal device is permitted). In this case, the response message of the third message can be a handover confirmation message, or in other words, the response message of the third message can be carried within the handover confirmation message. For example, the implementation of access control by the third network device can be found in the relevant description in step S106 above, and will not be repeated here.

[0271] If the first terminal device is within the avoidance area of ​​the third network device, or if the first terminal device is about to enter the avoidance area of ​​the third network device, the third network device may determine to reject the handover request of the first terminal device, and then send a third message response to the first network device. The third message response may indicate a handover rejection, and may include information indicating the reason for the handover rejection. In this case, the third message response may be a handover rejection message, or it may be carried within the handover rejection message.

[0272] Specifically, the implementation of the third network device's determination of whether to allow the first terminal device's access is similar to the implementation of the second network device's determination of whether to allow the first terminal device's access in step S902 above. For details, please refer to the relevant description in step S902 above, which will not be repeated here. Further, when the response message of the third message indicates that handover is allowed, after receiving the response message of the third message, the first network device can execute step S108, and then the first terminal device can execute step S109, thereby enabling the first terminal device to handover to the third network device. When the response message of the third message indicates that handover is refused, the implementation of the response message of the third message is similar to the implementation of the second message above. For details, please refer to the relevant description of the second message above, which will not be repeated here.

[0273] Optionally, if the response message of the third message indicates a refusal to handover, the first network device, upon receiving the response message of the third message, can determine that the first terminal device will not perform a handover, or it can send a handover request to the fourth network device. The method for determining the fourth network device is similar to that for the third network device, and details can be found in the description of the method for determining the third network device, which will not be repeated here.

[0274] Combining the two examples above, for instance, after step S902, as follows: Figure 12 As shown, the communication method also includes the following steps:

[0275] S906. The first network device determines the second area based on the second message and the location of the first terminal device.

[0276] Optionally, after receiving the second message, the first network device can define a certain area based on the location of the first terminal device and designate it as the second area.

[0277] For example, the first region and the second region may overlap (e.g., completely or partially overlap), or they may not overlap. Specifically, the second region may be the first region (i.e., the avoidance area of ​​the second network device), or the second region may be contained within the first region, or the second region may be a non-first region (i.e., the second region is not the avoidance area of ​​the second network device), or the second region may overlap with the first region.

[0278] If the reason for the handover rejection of the first terminal device is that the first terminal device is about to enter the first area, it indicates that the first terminal device is not in the first area but is close to it. In this case, the second area defined by the first network device may be a non-first area or overlap with the first area; that is, the second area or a portion of the second area (i.e., an area outside the first area) is close to the first area. Optionally, the first network device can determine the second area based on the wave position (e.g., the first wave position) of the first terminal device in multiple wave positions of the second network device. For example, when determining the second area, the first wave position may be included within the second area (i.e., the second area includes the coverage area of ​​the first wave position). Optionally, the first network device may use the coverage area of ​​the first wave position as the second area.

[0279] For example, based on the aforementioned relationship between the avoidance area and the wave position, it can be seen that the avoidance area typically contains at least one wave position, and for a wave position adjacent to the at least one area, it can be considered that a terminal device within the coverage area of ​​that wave position is about to enter the avoidance area. Therefore, taking the granularity of the second area as the wave position level as an example, the second area determined based on the wave position of the first terminal device in the multiple wave positions of the second network device may be a certain wave position among the at least one wave position, in which case the first area contains the second area (i.e., the first area and the second area overlap). Alternatively, it may be an adjacent wave position of at least one wave position, in which case the first area does not contain the second area (i.e., the first area and the second area do not overlap).

[0280] S907. If the second terminal device meets the handover conditions and the second network device is a candidate target network device, the first network device determines whether the second terminal device is located in the second area.

[0281] For example, the implementation of the second terminal device meeting the switching conditions is similar to the implementation of the first terminal device meeting the switching conditions in the above embodiments. For details, please refer to the relevant descriptions in the above embodiments, which will not be repeated here.

[0282] S908. If the second terminal device is located in the second area, the first network device determines that the second terminal device will not switch to the second network device.

[0283] Optionally, when there are other terminal devices (hereinafter referred to as the second terminal devices) among the terminal devices provided by the first network device that meet the handover conditions and wish to hand over to the second network device, the first network device can determine whether the second terminal device is located in the second area based on the second area it has determined.

[0284] As described above, for a second terminal device located in the second area, even if the first network device sends a handover request to the second network device, the second network device will refuse the handover because the second terminal device is located in the first area, or is about to enter the first area. Therefore, the first network device can directly determine whether to send a handover request to the second network device based on whether the second terminal device is located in the second area. If the second terminal device is located in the second area, there is no need to send a handover request; the first network device can directly determine that it will not hand over to the second network device, thereby reducing signaling interaction between the first and second network devices and saving signaling overhead. If the second terminal device is not located in the second area (i.e., the second terminal device is located outside the second area), it can send a handover request to the second network device, and the second network device can further determine whether to allow the handover based on the location of the second terminal device.

[0285] For example, the implementation of the second network device determining whether to allow the second terminal device to access is similar to the implementation of the second network device determining whether to allow the first terminal device to access in the above embodiments, and can be found in the relevant descriptions in the above embodiments; in addition, the implementation of the first network device determining that the second terminal device should not switch to the second network device is similar to the implementation of the first network device determining that the first terminal device should not switch to the second network device in the above embodiments, and can be found in the relevant descriptions in the above embodiments; it will not be repeated here.

[0286] See Figure 13 This illustrates a flowchart of another communication method provided in an embodiment of this application, such as... Figure 13 As shown, taking the first communication device as the first network device, the second communication device as the second network device, and the third communication device as the terminal device as an example, that is, taking the interaction between the first network device, the second network device, and the terminal device as an example, the method may include:

[0287] S1301, The first network device acquires the first area, and the second network device prohibits communication within the first area. The second network device is a candidate target network device for the terminal device, and the first network device is the source network device for the terminal device.

[0288] For example, since communication is prohibited for the second network device in the first area, the first area can be considered a avoidance area for the second network device. Specifically, the implementation of the avoidance area for the second network device can be found above. Figure 9 , Figures 11-12 The relevant descriptions in the document will not be repeated here.

[0289] For example, the implementation of the second network device is the same as described above. Figure 9 , Figures 11-12The implementation of the second network device is similar; please refer to the above for details. Figure 9 , Figures 11-12 The relevant descriptions in the document will not be repeated here.

[0290] Optionally, the first network device can obtain the first area from the second network device; that is, the second network device informs the first network device of its avoidance area. Therefore, step S1301 can be replaced by: the second network device sending a fifth message to the first network device; correspondingly, the first network device receives the fifth message from the second network device. The fifth message is used to indicate the first area.

[0291] For example, based on the aforementioned relationship between the avoidance area and the wave position, it can be seen that the avoidance area may include a portion of the wave positions of the network device; thus, the second network device can indirectly indicate its avoidance area by instructing the first network device on the communication status of each of its multiple wave positions.

[0292] Taking the second network device containing wave positions #0 to #7 as an example, the fifth message can instruct that communication is prohibited (or that wave positions #0 to #2 are disturbed) within wave positions #0 to #7, while normal communication is allowed under wave positions #3 to #7. Therefore, after receiving the fifth message, the first network device learns that wave positions #0 to #2 are the avoidance zone of the second network device (i.e., the first area includes wave positions #0 to #2). Furthermore, although normal communication is possible under wave position #3, since wave position #3 is an adjacent wave position to the avoidance zone, it can be assumed that the terminal device under that wave position is about to enter the avoidance zone.

[0293] Specifically, the fifth message can also be called the beam position arrangement information of the second network device, or the fifth message can be contained within the beam position arrangement information of the second network device. The beam position arrangement information of the second network device is used to indicate the specific beam position status of the second network device (such as communication status).

[0294] It is understood that beam position planning information is merely an exemplary term. In reality, beam position planning information can also be called beam position information, beam position information, etc., and this application does not limit it.

[0295] Optionally, since the network device described in this application is a satellite, and satellites are constantly moving, their avoidance zones can also be constantly changing. Therefore, a network device can update its avoidance zone and then inform other network devices of its latest avoidance zone. Alternatively, it can inform other network devices of its latest avoidance zone when requested by those devices.

[0296] For example, when updating its avoidance zone, the second network device can proactively inform the first network device of its latest avoidance zone. Alternatively, when the first network device needs to know the avoidance zone of the second network device (e.g., among the terminal devices served by the first network device, there is a terminal device that meets the handover conditions and wants to switch to the second network device), it sends an instruction to the second network device, and the second network device, upon receiving the instruction, informs the first network device of its latest avoidance zone.

[0297] S1302. When the terminal device meets the handover conditions, the first network device determines whether the terminal device is located in the first area, or whether the terminal device will move to the first area within the first time period.

[0298] For example, the implementation of the terminal device meeting the handover conditions is the same as the implementation of the first terminal device meeting the handover conditions in step S901 above, and the specific details can be found in the relevant description in step S901 above; the implementation of the first time period can also be found in the above. Figure 9 , Figures 11-12 The relevant descriptions in the document will not be repeated here.

[0299] S1303, The first network device determines whether the terminal device should switch to the second network device based on the judgment result.

[0300] Specifically, if the determination result is that the terminal device is not in the first area and will not move to the first area within the first time period, the first network device determines that the terminal device can switch to the second network device; if the determination result is that the terminal device is in the first area, or the terminal device will move to the first area within the first time period, the first network device determines that the terminal device will not switch to the second network device.

[0301] For example, if the first network device determines that the terminal device can switch to the second network device, it can send a switch request to the second network device. Specifically, when the first network device determines that the terminal device can switch to the second network device, the interaction between the first network device, the terminal device, and the second network device can participate in the implementation of the above steps S105 to S109, so that the terminal device can switch to the second network device.

[0302] For example, if the terminal device is located within the first area, or if the terminal device will move to the first area within the first time period, normal communication cannot be guaranteed even if the terminal device switches to the second network device. Therefore, the first network device can determine in advance before switching. If the terminal device is located within the first area, or if the terminal device will move to the first area within the first time period, it can consider not switching the terminal device to the second network device, thus avoiding sending a switching request to the second network device, reducing signaling interaction between the first and second network devices, and saving signaling overhead. Otherwise, a switching request can be sent to the second network device.

[0303] For example, determining that the terminal device will not switch to the second network device may include: the first network device determining that the terminal device will not perform a handover, or the first network device not sending a handover request to the second network. Furthermore, if the first network device does not send a handover request to the second network device, the first network device may also consider determining whether the terminal device can consider switching to another network device (such as a third network device).

[0304] The implementation of the third network device is similar to the above. Figure 9 , Figures 11-12 The implementation of the third network device is similar, meaning the third network device is also a candidate target network device for the terminal device; see the above for details. Figure 9 , Figures 11-12 The relevant descriptions in the document will not be repeated here.

[0305] Specifically, if the first network device does not send a handover request to the second network device, the first network device can determine whether the terminal device is located within the avoidance zone of the third network device (hereinafter referred to as the third zone), or whether the terminal device will move to the third zone during the second time period. If the terminal device is located within the third zone, or will move to the third zone during the second time period, normal communication cannot be guaranteed even if the terminal device is switched to the third network device. Therefore, the first network device can determine in advance before the handover that if the terminal device is located within the third zone, or will move to the third zone during the second time period, it can consider not switching the terminal device to the third network device, thus avoiding sending a handover request to the third network device, reducing signaling interaction between the first and third network devices, and saving signaling overhead. Otherwise, a handover request can be sent to the third network device.

[0306] The third area is known to the first network device in advance. That is, before the first network device determines whether the terminal device is located in the avoidance area of ​​the third network device (hereinafter referred to as the third area), or whether the terminal device will move into the third area within the first time period, the first network device also needs to obtain the third area.

[0307] For example, the implementation of the first network device acquiring the third region is similar to the implementation of the first network device acquiring the first region, that is, the second network device informs the first network device of the third region. For example, the third network device sends a sixth message to the first network device; correspondingly, the first network device receives the sixth message from the third network device. The sixth message is used to indicate the third region.

[0308] Specifically, the implementation of the sixth message is similar to that of the fifth message mentioned above, and you can refer to the relevant description of the fifth message mentioned above for details; in addition, the implementation of the second time period is similar to that of the first time period mentioned above, and you can refer to the relevant description of the first time period mentioned above for details; it will not be repeated here.

[0309] based on Figure 13 The method described above allows the source network device (i.e., the first network device) of the terminal device to pre-observe the avoidance zones of other network devices (e.g., the avoidance zone of the second network device is the first zone, where communication is prohibited for the network device within the avoidance zone). Therefore, when the terminal device meets the handover conditions and needs to switch to the second network device, it can first determine whether the terminal device is located within the avoidance zone, or whether the terminal device is about to enter the avoidance zone. If so, it means that even if the terminal device switches to the second network device, normal communication cannot be guaranteed. Therefore, the first network device considers not switching the terminal device to the second network device, thus avoiding sending a handover request to the second network device, reducing signaling interaction between the first and second network devices, and saving signaling overhead. Furthermore, the terminal device can choose to switch to other candidate target network devices to ensure data transmission and improve user experience.

[0310] It should be noted that the various embodiments of this application can be implemented independently or in combination, without limitation. Unless otherwise specified or in conflict, at least one of the terms or descriptions in the different embodiments provided in this application is consistent and can be referenced by each other. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.

[0311] The foregoing primarily describes the solutions provided in this application from the perspective of device-to-device interaction. It is understood that each device, in order to achieve the aforementioned functions, includes at least one of the hardware structures or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, in conjunction with the algorithm steps of the examples described in the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0312] It is understood that, in order to achieve the above-mentioned functions, the communication device includes at least one of the hardware structures or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, based on the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0313] This application embodiment can divide each device into functional modules according to the above method example. For example, each function can be divided into a separate functional module, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware or as a software functional module. It should be noted that the module division in this application embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0314] Figure 14 A schematic diagram of a communication device 1400 is shown. The communication device 1400 includes a processing module 1401 and a transceiver module 1402. This communication device can be used to implement the functions of the aforementioned first network device or second network device.

[0315] In some embodiments, the communication device 1400 may further include a storage module. Figure 14 (not shown), used to store at least one of a program, instruction, or data.

[0316] In some embodiments, the transceiver module 1402, also referred to as a transceiver unit, is used to implement at least one of the functions of sending or receiving. The transceiver module 1402 may consist of a transceiver circuit, a transceiver, a transceiver unit, or a communication interface.

[0317] In some embodiments, the transceiver module 1402 may include a receiving module and a sending module, respectively configured to perform receiving and sending steps performed by the first network device or the second network device in the above method embodiments, or to support at least one of other processes in which the technology described herein is performed; the processing module 1401 may be configured to perform processing steps (e.g., determining) performed by the first network device or the second network device in the above method embodiments, or to support at least one of other processes in which the technology described herein is performed.

[0318] When the communication device 1400 is used to implement the functions of the first network device described above:

[0319] In some embodiments, the transceiver module 1402 is configured to send a first message and receive a second message. The first message requests a switch from a first terminal device to a second network device, where the first network device is the source network device of the first terminal device and the second network device is a candidate target network device for the first terminal device. The second message indicates a refusal to switch, including indication information of the reason for the refusal. The reason for the refusal includes: the first terminal device is located within a first area; or, the first terminal device will move to the first area within a first time period. The second network device is prohibited from communication within the first area.

[0320] Optionally, the first message is a switch request message.

[0321] Optionally, the second message may be a handover rejection message, or a handover preparation failure message.

[0322] Optionally, the first area is a avoidance area for the second network device.

[0323] Optionally, the processing module 1401 is used to determine, based on the second message, that the first terminal device will not perform a handover.

[0324] Optionally, the transceiver module 1402 is also used to send a third message, which is used to request the first terminal device to be switched to a third network device. The third network device is a candidate target network device, and the second network device is different from the third network device.

[0325] Optionally, the processing module 1401 is further configured to determine a second region based on the second message and the location of the first terminal device; and if the second terminal device meets the handover conditions and the second network device is a candidate target network device, determine whether the second terminal device is located in the second region; and if the second terminal device is located in the second region, determine that the second terminal device will not handover to the second network device.

[0326] Optionally, the first terminal device is located within the coverage area of ​​the first wave position, which is one of the multiple wave positions of the second network device; correspondingly, the second area includes the coverage area of ​​the first wave position.

[0327] Optionally, the indication information for the reason for refusing to switch includes a first reason value, which indicates that the first terminal device is located in the first area, or that the first reason value indicates that the first terminal device will move to the first area within the first time period.

[0328] Optionally, the indication information for the reason for refusing to switch includes a first reason value. The first reason value is the reason value corresponding to the reason for refusing to switch among the multiple reasons for refusing to switch in the first correspondence relationship. The first correspondence relationship includes the correspondence between multiple reason values ​​and multiple reasons for refusing to switch.

[0329] Optionally, the transceiver module 1402 is also used to send a fourth message, which is used to indicate the location information of the first terminal device, and the location information of the first terminal device is used to determine the second message.

[0330] Optionally, the first message may also be used to indicate the location information of the first terminal device, and the location information of the first terminal device may be used to determine the second message.

[0331] Optionally, the transceiver module 1402 is further configured to include the location information of the first terminal device in the information of the first wave position, wherein the first wave position is one of the multiple wave positions of the second network device, and the first terminal device is located within the coverage area of ​​the first wave position.

[0332] In other embodiments, the processing module 1401 is configured to acquire a first area, wherein a second network device is prohibited from communication within the first area, the second network device is a candidate target network device for the first terminal device, and the first network device is a source network device for the first terminal device; and, if the terminal device meets the handover conditions, determine whether the terminal device is located within the first area, or whether the terminal device will move to the first area within a first time period; and determine whether to handover the terminal device to the second network device based on the determination result. Specifically, if the determination result is that the terminal device is not located within the first area and will not move to the first area within the first time period, the first network device may send a handover request to the second network device; if the determination result is that the terminal device is located within the first area, or will move to the first area within the first time period, the first network device determines that the terminal device will not handover to the second network device.

[0333] Optionally, the transceiver module 1402 is used to receive a fifth message from the second network device, the fifth message being used to indicate the first area.

[0334] Optionally, the processing module 1401 is further configured to obtain the second area, and the third network device is prohibited from communicating in the third area; determine whether the terminal device is located in the third area, or whether the terminal device will move to the third area during the second time period; and determine that the terminal device will not switch to the third network device if the terminal device is located in the third area, or if the terminal device will move to the third area during the second time period.

[0335] Optionally, the transceiver module 1402 is also configured to receive a sixth message from a third network device, the sixth message being used to indicate a third area.

[0336] When the communication device 1400 is used to implement the functions of the second network device described above:

[0337] In some embodiments, the transceiver module 1402 is configured to receive a first message and send a second message; wherein the first message is configured to request the first terminal device to be switched to a second network device, the second network device being a candidate target network device for the first terminal device, and the second message is configured to indicate a refusal to switch, the second message including indication information of the reason for the refusal to switch; the reason for the refusal to switch includes: the first terminal device is located in a first area; or, the first terminal device will move to the first area within a first time period; wherein the second network device is prohibited from communication in the first area.

[0338] Optionally, the first message is a switch request message.

[0339] Optionally, the second message may be a handover rejection message, or a handover preparation failure message.

[0340] Optionally, the first area is a avoidance area for the second network device.

[0341] Optionally, the indication information for the reason for refusing to switch includes a first reason value, which indicates that the first terminal device is located in the first area, or that the first reason value indicates that the first terminal device will move to the first area within the first time period.

[0342] Optionally, the indication information for the reason for refusing to switch includes a first reason value. The first reason value is the reason value corresponding to the reason for refusing to switch among the multiple reasons for refusing to switch in the first correspondence relationship. The first correspondence relationship includes the correspondence between multiple reason values ​​and multiple reasons for refusing to switch.

[0343] Optionally, the transceiver module 1402 is also configured to receive a fourth message, which indicates the location information of the first terminal device; the transceiver module 1402 is also configured to send a second message based on the fourth message.

[0344] Optionally, the first message is also used to indicate the location information of the first terminal device; the transceiver module 1402 is also used to send a second message according to the first message.

[0345] Optionally, the transceiver module 1402 is further configured to include the location information of the first terminal device in the information of the first wave position, wherein the first wave position is one of the multiple wave positions of the second network device, and the first terminal device is located within the coverage area of ​​the first wave position.

[0346] All relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.

[0347] In this application, the communication device (i.e., the first network device or the second network device) 1400 is presented in an integrated manner, divided into various functional modules. Here, "module" may refer to at least one of the following: ASIC, circuit, processor and memory executing one or more software or firmware programs, integrated logic circuit, or other device that can provide the above-mentioned functions.

[0348] In some embodiments, when Figure 14 When the communication device 1400 is a chip or chip system, the function / implementation process of the transceiver module 1402 can be implemented through the input / output interface (or communication interface) of the chip or chip system, and the function / implementation process of the processing module 1401 can be implemented through the processor (or processing circuit) of the chip or chip system.

[0349] Since the communication device 1400 provided in this embodiment can execute the above method, the technical effects it can achieve can be referred to the above method embodiment, and will not be repeated here.

[0350] As another possible product form, the first network device or the second network device described in the embodiments of this application can both adopt... Figure 15 The shown composition structure, or including Figure 15 The components shown. Figure 15 This is a schematic diagram illustrating the composition of a communication device 1500 provided in an embodiment of this application. The communication device 1500 can be a first network device or a chip or system-on-a-chip within the first network device; it can also be a second network device or a chip or system-on-a-chip within the second network device. For example... Figure 15 As shown, the communication device 1500 includes a processor 1501, a communication interface 1502, and a communication line 1503.

[0351] Furthermore, the communication device 1500 may also include a memory 1504. The processor 1501, the memory 1504, and the communication interface 1502 can be connected via a communication line 1503.

[0352] The processor 1501 can be a CPU, a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The processor 1501 can also be other devices with processing capabilities, such as circuits, devices, or software modules, without limitation.

[0353] Communication interface 1502 is used for communication with other devices or other communication networks. These other communication networks can be Ethernet, radio access network (RAN), wireless local area networks (WLAN), etc. Communication interface 1502 can be a module, circuit, transceiver, or any device capable of enabling communication.

[0354] Communication line 1503 is used to connect different components in communication device 1500, enabling communication between them. Communication line 1503 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. This bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 15 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0355] The memory 1504 may be a device with storage function, used to store at least one of instructions or data. The instructions may be computer programs.

[0356] For example, the memory 1504 may be at least one of read-only memory (ROM) or other types of static storage devices capable of storing static information or instructions; it may also be at least one of random access memory (RAM) or other types of dynamic storage devices capable of storing information or instructions; it may also be electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, etc., without limitation.

[0357] It should be noted that the memory 1504 can exist independently of the processor 1501, or it can be integrated with the processor 1501. The memory 1504 can be used to store instructions, program code, or some data, etc. The memory 1504 can be located inside or outside the communication device 1500, without limitation. The processor 1501 is used to execute the instructions stored in the memory 1504 to implement the communication method provided in the following embodiments of this application.

[0358] In one example, processor 1501 may include one or more CPUs, for example Figure 15 CPU0 and CPU1 in the CPU.

[0359] In some embodiments, those skilled in the art will recognize that the communication device 1400 can be implemented in hardware using... Figure 15 The communication device shown is in the form of 1500.

[0360] As an example, Figure 14 The function / implementation process of the processing module 1401 can be achieved through... Figure 15 The processor 1501 in the communication device 1500 shown calls computer execution instructions stored in memory 1504 to implement the function. Figure 14 The function / implementation process of the transceiver module 1402 can be obtained through Figure 15 This is achieved through the communication interface 1502 in the communication device 1500 shown.

[0361] As an optional implementation, the communication device 1500 includes multiple processors, for example, besides Figure 15 In addition to processor 1501, it may also include processor 1507.

[0362] As an optional implementation, the communication device 1500 also includes an output device 1505 and an input device 1506. Exemplarily, the input device 1506 is a liquid crystal display (LCD), a light-emitting diode (LED) display device, a cathode ray tube (CRT) display device, or a projector, etc. For example, the input device 1506 can be a keyboard, mouse, microphone, joystick, touchscreen device, or sensing device, etc. The output device 1505 is a display screen, a speaker, etc.

[0363] It should be noted that the communication device 1500 can be a desktop computer, laptop computer, network server, mobile phone, tablet computer, wireless terminal, embedded device, chip system, or something similar. Figure 15 Equipment with a similar structure. Furthermore... Figure 15 The structural composition shown does not constitute a limitation on the communication device, except... Figure 15 In addition to the components shown, the communication device may include more or fewer components than illustrated, or combine certain components, or have different component arrangements.

[0364] In this embodiment of the application, the chip system may be composed of chips or may include chips and other discrete devices.

[0365] As another possible product form, the first network device or the second network device described in the embodiments of this application can be implemented using a general bus architecture. For ease of explanation, see [link to documentation]. Figure 16 , Figure 16 This is a schematic diagram of the structure of a communication device 1600 provided in an embodiment of this application. The communication device 1600 includes a processor 1601 and a transceiver 1602. The communication device 1600 can be a first network device, or a chip or chip system therein; or, the communication device 1600 can be a second network device, or a chip or module therein. Figure 14 The function / implementation process of the transceiver module 1402 can be obtained through Figure 16 This is implemented using the transceiver 1602 in the communication device 1600 shown; similarly, Figure 14 The function / implementation process of the processing module 1401 can be achieved through... Figure 16 This is implemented by the processor 1601 in the communication device 1600 shown.

[0366] Figure 16 Only the main components of the communication device 1600 are shown. In addition to the processor 1601 and transceiver 1602, the communication device may further include a memory 1603.

[0367] Optionally, the processor 1601 is mainly used to process communication protocols and communication data, control the entire communication device, execute software programs, and process the data of the software programs. The memory 1603 is mainly used to store software programs and data. The transceiver 1602 may include radio frequency (RF) circuitry and an antenna. The RF circuitry is mainly used for converting baseband signals to RF signals and processing RF signals. The antenna is mainly used for transmitting and receiving RF signals in the form of electromagnetic waves.

[0368] Optionally, the processor 1601, transceiver 1602, and memory 1603 can be connected via a communication bus.

[0369] When the communication device is powered on, the processor 1601 can read the software program in the memory 1603, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be transmitted wirelessly, the processor 1601 performs baseband processing on the data to be transmitted and outputs the baseband signal to the radio frequency (RF) circuit. The RF circuit processes the baseband signal and transmits the RF signal outward in the form of electromagnetic waves through the antenna. When data is sent to the communication device, the RF circuit receives the RF signal through the antenna, converts the RF signal into a baseband signal, and outputs the baseband signal to the processor 1601. The processor 1601 converts the baseband signal into data and processes the data.

[0370] In some embodiments, transceiver 1602 may include a transmitter and a receiver, wherein the transmitter is used to implement the transmission operation in the above method embodiments; and the receiver is used to implement the reception operation in the above method embodiments.

[0371] For example, when the communication device is a chip, the chip may not include the memory 1603; that is, the communication device includes a processor 1601 and a transceiver 1602. In this case, the transceiver 1602 is the input / output interface of the chip, wherein the transmitter in the transceiver corresponds to the output interface of the chip, and the receiver in the transceiver corresponds to the input interface of the chip.

[0372] In some embodiments, this application also provides a communication device, which includes a processor for implementing the methods in any of the above method embodiments.

[0373] As one possible implementation, the communication device also includes a memory. This memory stores necessary computer programs or instructions. The processor can invoke the computer programs or instructions in the memory to cause the communication device to execute the methods in any of the above method embodiments. Alternatively, the memory may be external and not located within the communication device.

[0374] As another possible implementation, the communication device also includes an interface circuit, which is a code / data read / write interface circuit, used to receive computer execution instructions (which are stored in memory and may be read directly from memory or may be transmitted through other devices) and transmit them to the processor.

[0375] As another possible implementation, the communication device also includes a communication interface for communicating with modules outside the communication device.

[0376] It is understood that the communication device can be a chip or a chip system. When the communication device is a chip system, it can be composed of chips or may include chips and other discrete devices. This application does not specifically limit this.

[0377] This application also provides a computer-readable storage medium having a computer program or instructions stored thereon, which, when executed by a computer, implements the functions of any of the above-described method embodiments.

[0378] This application also provides a computer program product that, when executed by a computer, implements the functions of any of the above method embodiments.

[0379] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0380] It is understood that the systems, apparatuses, and methods described in this application can also be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the couplings or direct couplings or communication connections shown or discussed may be through some interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0381] The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. The components shown as units may or may not be physical units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0382] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0383] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented using software programs, implementation can be, in whole or in part, in the form of a computer program product. This computer program product includes one or more computer instructions. When the computer program or instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device containing one or more servers, data centers, etc., that can be integrated with the medium. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state drive (SSD)). In this embodiment, the computer may include the aforementioned apparatus.

[0384] Although this application has been described herein in conjunction with various embodiments, those skilled in the art, by reviewing the accompanying drawings, disclosure, and appended claims, will understand and implement other variations of the disclosed embodiments in carrying out the claimed application. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce good results.

Claims

1. A communication method, characterized in that, The method is applied to a first network device, and the method includes: Send a first message to the second network device, the first message being used to request the first terminal device to switch to the second network device, the first network device being the source network device of the first terminal device, and the second network device being a candidate target network device of the first terminal device; Receive a second message from the second network device, the second message indicating a refusal to handover, the second message including indication information of the reason for the refusal to handover; The reasons for refusing to switch include: the first terminal device is located in the first area, or the first terminal device will move to the first area during the first time period; the second network device is prohibited from communicating in the first area.

2. The method according to claim 1, characterized in that, The first message is a handover request message.

3. The method according to claim 1 or 2, characterized in that, The second message is either a handover rejection message or a handover preparation failure message.

4. The method according to any one of claims 1-3, characterized in that, The first area is the avoidance area for the second network device.

5. The method according to any one of claims 1-4, characterized in that, The method further includes: Based on the second message, it is determined that the first terminal device will not perform a handover.

6. The method according to any one of claims 1-4, characterized in that, The method further includes: A third message is sent to a third network device, the third message being used to request the first terminal device to switch to the third network device, the third network device being a candidate target network device for the first terminal device, and the second network device being different from the third network device.

7. The method according to any one of claims 1-6, characterized in that, The method further includes: Based on the second message and the location of the first terminal device, determine the second region; If the second terminal device meets the handover conditions and the second network device is a candidate target network device, determine whether the second terminal device is located in the second area; If the second terminal device is located in the second area, it is determined that the second terminal device will not switch to the second network device.

8. The method according to claim 7, characterized in that, The first terminal device is located within the coverage area of ​​the first wave position, which is one of the multiple wave positions of the second network device; Accordingly, the second region includes the coverage area of ​​the first wave position.

9. The method according to any one of claims 1-8, characterized in that, The indication information for the reason for refusing to switch includes a first reason value, which indicates that the first terminal device is located in a first area, or that the first reason value indicates that the first terminal device will move to the first area within a first time period.

10. The method according to any one of claims 1-9, characterized in that, The indication information for the reason for refusing to switch includes a first reason value. The first reason value is the reason value corresponding to the reason for refusing to switch among the multiple reasons for refusing to switch in the first correspondence relationship. The first correspondence relationship includes the correspondence between multiple reason values ​​and multiple reasons for refusing to switch.

11. The method according to any one of claims 1-10, characterized in that, Before receiving the second message, the method further includes: A fourth message is sent to the second network device, the fourth message being used to indicate the location information of the first terminal device, and the location information of the first terminal device being used to determine the second message.

12. The method according to any one of claims 1-10, characterized in that, The first message is also used to indicate the location information of the first terminal device, and the location information of the first terminal device is used to determine the second message.

13. The method according to claim 11 or 12, characterized in that, The location information of the first terminal device includes information about a first wave position, which is one of multiple wave positions of the second network device, and the first terminal device is located within the coverage area of ​​the first wave position.

14. A communication method, characterized in that, The method is applied to a second network device, and the method includes: Receive a first message from a first network device, the first message being used to request switching the first terminal device to the second network device, the second network device being a candidate target network device for the first terminal device, and the first network device being the source network device for the first terminal device; Send a second message to the first network device, the second message being used to indicate that the handover is refused, the second message including indication information of the reason for the handover refusal; The reasons for refusing to switch include: the first terminal device is located in the first area, or the first terminal device will move to the first area during the first time period; the second network device is prohibited from communicating in the first area.

15. The method according to claim 14, characterized in that, The first message is a handover request message.

16. The method according to claim 14 or 15, characterized in that, The second message is either a handover rejection message or a handover preparation failure message.

17. The method according to any one of claims 14-16, characterized in that... The first area is the avoidance area for the second network device.

18. The method according to any one of claims 14-17, characterized in that, The indication information for the reason for refusing to switch includes a first reason value, which indicates that the first terminal device is located in a first area, or that the first reason value indicates that the first terminal device will move to the first area within a first time period.

19. The method according to any one of claims 14-18, characterized in that, The indication information for the reason for refusing to switch includes a first reason value. The first reason value is the reason value corresponding to the reason for refusing to switch among the multiple reasons for refusing to switch in the first correspondence relationship. The first correspondence relationship includes the correspondence between multiple reason values ​​and multiple reasons.

20. The method according to any one of claims 14-19, characterized in that, Before sending the second message, the method further includes: Receive a fourth message from the first network device, the fourth message being used to indicate the location information of the first terminal device; Sending the second message includes: sending the second message according to the fourth message.

21. The method according to any one of claims 14-19, characterized in that, The first message is also used to indicate the location information of the first terminal device; Sending the second message includes: sending the second message based on the first message.

22. The method according to claim 20 or 21, characterized in that, The location information of the first terminal device includes information about a first wave position, which is one of multiple wave positions of the second network device, and the first terminal device is located within the coverage area of ​​the first wave position.

23. A communication device, characterized in that, The communication device includes a processor; the processor is configured to run a computer program or instructions to cause the communication device to perform the method as described in any one of claims 1-13; or to cause the communication device to perform the method as described in any one of claims 14-22.

24. The communication device according to claim 23, characterized in that, The communication device further includes a memory; the memory is used to store the computer program or instructions.

25. A computer-readable storage medium, characterized in that, A computer-readable storage medium stores computer instructions or programs that, when run on a computer, cause the method described in any one of claims 1-13 to be performed, or cause the method described in any one of claims 14-22 to be performed.

26. A computer program product, characterized in that, The computer program product includes a computer program or instructions; when some or all of the computer instructions are run on a computer, they cause the method as described in any one of claims 1-13 to be performed; or cause the method as described in any one of claims 14-22 to be performed.

27. A chip, characterized in that, include: A processor for executing computer program instructions that cause a communication device including the chip to perform the method as described in any one of claims 1-13; or, cause a communication device including the chip to perform the method as described in any one of claims 14-22.

28. The chip according to claim 27, characterized in that, The chip also includes a memory for storing the computer program instructions.

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