Satellite-based communication method and apparatus, and computer-readable medium and electronic device

Abstract

Provided in the embodiments of the present application are a satellite-based communication method and apparatus, and a computer-readable medium and an electronic device. At least a satellite-borne base station is deployed on a satellite. The communication method comprises: acquiring availability information of a service link between a satellite-borne base station and a user equipment; and exposing the availability information of the service link to an application function entity, wherein the availability information of the service link serves as a basis for the application function entity to send data to the user equipment by means of the satellite-borne base station.

Description

Satellite-based communication method, device, computer-readable medium, and electronic device

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on April 3, 2024, with application number 2024104048751, and invention name “Satellite-based communication methods, devices, computer-readable media and electronic devices”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of computer and communication technology, and in particular, to a satellite-based communication method, device, computer-readable medium, and electronic device. Background Art

[0003] In wireless communication technology research, satellite communications are considered a key future development direction. Satellite communications refers to the technology by which terrestrial wireless communication devices access a network via satellite, or by the technology by which terrestrial wireless communication devices communicate with each other using satellites as relays. Satellite communications offer a wide range and are less susceptible to land-based disasters. As a complementary access method for mobile communications, satellite communications effectively address the limited coverage and high construction costs of mobile communication systems.

[0004] Satellite communication systems and terrestrial mobile networks, such as 4G and 5G networks, can be integrated to form a global, seamless, integrated communications network covering land, sea, air, and space, meeting the diverse service needs of users everywhere. In practical applications, base stations may be deployed on satellites to create satellite-borne base stations, which establish service links with user equipment (UE).

[0005] Technical content

[0006] The embodiments of the present application provide a satellite-based communication method, apparatus, computer-readable medium, and electronic device, which enable the application end to perceive the availability information of the service link, and then transmit service data to the user equipment based on the availability information of the service link, thereby realizing intelligent transmission of service data, which is conducive to improving data transmission efficiency and reducing the processing load of the base station.

[0007] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0008] An embodiment of the present application provides a satellite-based communication method, which is executed by a core network network element. At least a satellite base station is deployed on the satellite. The communication method includes: obtaining availability information of a service link between the satellite base station and a user device; opening the availability information of the service link to an application function entity, wherein the availability information of the service link serves as a basis for the application function entity to send data to the user device through the satellite base station.

[0009] An embodiment of the present application also provides a satellite-based communication method, which is executed by an application function entity, where at least a satellite base station is deployed on the satellite. The communication method includes: receiving availability information of a service link sent by a core network network element, where the service link is a communication link established between the satellite base station and a user device; and sending data to the user device through the service link based on the availability information of the service link.

[0010] An embodiment of the present application also provides a satellite-based communication device, which is deployed on a core network network element, and at least a satellite base station is deployed on the satellite. The communication device includes: an acquisition unit, configured to obtain availability information of a service link between the satellite base station and a user device; a sending unit, configured to open the availability information of the service link to an application function entity, wherein the availability information of the service link serves as a basis for the application function entity to send data to the user device through the satellite base station.

[0011] An embodiment of the present application also provides a satellite-based communication device, which is deployed on an application function entity, and at least a satellite base station is deployed on the satellite. The communication device includes: a receiving unit, configured to receive availability information of a service link sent by a core network network element, where the service link is a communication link established between the satellite base station and a user device; and a processing unit, configured to send data to the user device through the service link based on the availability information of the service link.

[0012] An embodiment of the present application further provides a computer-readable medium having a computer program stored thereon, and when the computer program is executed by a processor, the satellite-based communication method as described in the above embodiment is implemented.

[0013] An embodiment of the present application also provides an electronic device, comprising: one or more processors; a storage device for storing one or more computer programs, wherein when the one or more computer programs are executed by the one or more processors, the electronic device implements the satellite-based communication method as described in the above embodiment.

[0014] The present application also provides a computer program product, including a computer program stored in a computer-readable storage medium. A processor of an electronic device reads and executes the computer program from the computer-readable storage medium, causing the electronic device to perform the satellite-based communication method provided in the various optional embodiments described above.

[0015] In the technical solutions provided in some embodiments of the present application, the core network network element obtains the availability information of the service link between the satellite base station and the user equipment, and then opens the availability information of the service link to the application function entity, so that the application end can perceive the availability information of the service link, and then transmit business data to the user equipment based on the availability information of the service link, avoiding the problem of low data transmission efficiency caused by the application end transmitting business data when the service link is unavailable, realizing intelligent transmission of business data, which is conducive to improving data transmission efficiency and reducing the processing load of the base station.

[0016] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application.

[0017] BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 shows a diagram of a fusion network architecture between a satellite communication system and a terrestrial mobile network according to some embodiments of the present application.

[0019] FIG2 shows a diagram of a fusion network architecture between a satellite communication system and a terrestrial mobile network according to some embodiments of the present application.

[0020] FIG3 shows a diagram of a fusion network architecture between a satellite communication system and a terrestrial mobile network according to some embodiments of the present application.

[0021] FIG4 shows a diagram of a fusion network architecture between a satellite communication system and a terrestrial mobile network according to some embodiments of the present application.

[0022] FIG5 shows a flow chart of a satellite-based communication method according to some embodiments of the present application.

[0023] FIG6 shows a flowchart of a satellite-based communication method according to some embodiments of the present application.

[0024] FIG7 shows a diagram of a fusion network architecture between a satellite communication system and a terrestrial mobile network according to some embodiments of the present application.

[0025] FIG8 shows a signaling flow chart of service link availability opening according to some embodiments of the present application.

[0026] FIG9 shows a signaling flow chart of service link availability opening according to some embodiments of the present application.

[0027] FIG10 shows a signaling flow chart of service link availability opening according to some embodiments of the present application.

[0028] FIG11 shows a block diagram of a satellite-based communication device according to some embodiments of the present application.

[0029] FIG12 shows a block diagram of a satellite-based communication device according to some embodiments of the present application.

[0030] FIG13 shows a schematic structural diagram of a computer system suitable for implementing an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0031] Example embodiments will now be described in a more complete manner with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to these examples; rather, these embodiments are provided to make this application more comprehensive and complete and to fully convey the concepts of the example embodiments to those skilled in the art.

[0032] In addition, the features, structures or characteristics described in the present application may be combined in one or more embodiments in any suitable manner. In the following description, there are many specific details so that the embodiments of the present application can be fully understood. However, it will be appreciated by those skilled in the art that when implementing the technical solution of the present application, it is not necessary to use all the detailed features in the embodiments, one or more specific details may be omitted, or other methods, elements, devices, steps, etc. may be adopted.

[0033] In the embodiments of the present application, the term "module" or "unit" refers to a computer program or a part of a computer program that has a predetermined function and works together with other related parts to achieve a predetermined goal, and can be implemented in whole or in part by using software, hardware (such as processing circuits or memories) or a combination thereof. Similarly, a processor (or multiple processors or memories) can be used to implement one or more modules or units. In addition, each module or unit can be part of an overall module or unit that includes the function of the module or unit.

[0034] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically separate entities. That is, these functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0035] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, while others may be combined or partially combined. Therefore, the actual execution order may vary depending on the actual situation.

[0036] It should be noted that the term "plurality" used in this document refers to two or more. "And / or" describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. The character " / " generally indicates an "or" relationship between the associated objects.

[0037] The technical solution of the embodiments of this application mainly involves the integration of satellite communication systems and terrestrial mobile networks. This integration solution can form an integrated integrated communication network with seamless global coverage of sea, land, air, and space, meeting the various service needs of users everywhere. Among them, there are many modes for the integration of satellite communication systems and terrestrial mobile networks. The following is a brief introduction:

[0038] The converged model shown in Figure 1 can be called a transparent forwarding model. All core network functions and base stations are deployed on the ground. The satellite's service link and feedback link serve as the underlying link carriers of the Uu interface, supporting communication between the base station and user equipment (UE). The Uu interface is the interface between the base station and the UE, used to transmit signaling and data. The gateway (which can be a gateway deployed on the ground, also known as a ground gateway; it can also be a general term for gateways deployed on satellites and gateways deployed on the ground) communicates with the core network through the base station; the core network communicates with the application server. In the transparent forwarding model shown in Figure 1, the satellite is only responsible for relaying signals between the UE and the base station. All relevant protocol processing of the mobile communication network is carried out within the mobile communication network.

[0039] It should be noted that the core network can be an evolved packet core (EPC), a 5G core network (5GC), or a core network of a future evolved mobile communication system. The base station can be an evolved Node B (eNB or eNodeB) in a 4G communication system or a gNB in ​​a 5G communication system. The gateway is a gateway deployed on the ground for communicating with satellites, such as a non-terrestrial network gateway (NTN-GW), other gateways, or other devices that perform similar functions.

[0040] The transparent forwarding model shown in Figure 1 suffers from high latency due to the ground-based deployment of base stations and core network equipment. Furthermore, since this model treats satellites solely as signal relay links, without utilizing them for signal processing or conversion, communication between satellites cannot be achieved. Consequently, this model does not support inter-satellite links (ISLs), making it difficult to leverage satellite constellations to expand coverage of the Earth's surface. Furthermore, the path between satellites and base stations is long, resulting in significant latency.

[0041] The fusion mode shown in Figures 2 and 3 can be called a regeneration mode, that is, the base station (as shown in Figure 2) or the base station and some core network elements (as shown in Figure 3) are placed on the satellite. This can shorten the link processing delay and realize satellite networking through ISL as shown in Figure 4.

[0042] Specifically, as shown in Figure 2, the base station (for example, eNB, gNB, etc.) is deployed on the satellite, which is called a satellite base station; the core network (for example, EPC, 5GC, etc.) is deployed on the ground. The satellite base station can have local data forwarding capabilities, that is, data transmission between different UEs can be achieved through the satellite base station without going through the ground core network, which optimizes data routing and saves transmission resources. Specifically, the data sent by a UE is transmitted to the satellite base station through the service link between the satellite base station, and then the satellite base station sends the data to another UE based on the service link between the satellite base station and another UE. In the embodiment shown in Figure 2, the core network is connected to the application server. When the UE needs to communicate with the application server, it is necessary to establish a communication connection with the core network based on the feedback link between the satellite base station and the gateway, and then realize the communication interaction with the application server based on the core network.

[0043] In the network architecture shown in FIG3 , a base station (e.g., an eNB, gNB, etc.) is deployed on a satellite, referred to as an onboard base station. At the same time, some core network elements (e.g., EPC, 5GC, etc.) can also be deployed on the satellite. The onboard base station can have local data forwarding capabilities, that is, data transmission between different UEs can be achieved through the onboard base station without going through the terrestrial core network, optimizing data routing and saving transmission resources. Specifically, data sent by a UE is transmitted to the onboard base station via a service link between the onboard base station and the satellite base station, and then the satellite base station sends the data to another UE based on the service link between the onboard base station and the satellite base station. At the same time, since some core network elements are deployed on the satellite, some UE management (such as access and mobility management, session management, policy management, etc.) can be achieved even without interacting with the terrestrial core network. In addition, in the embodiment shown in FIG3 , the terrestrial core network is connected to the application server. When the UE needs to communicate with the application server, it needs to establish a communication connection with the core network based on the feedback link between the onboard base station and the gateway, and then implement communication interaction with the application server based on the core network. In some embodiments, if an application server is also deployed on the satellite, the UE may also interact with the application server deployed on the satellite.

[0044] In the network architecture shown in Figure 4, the base station (eNB, gNB, etc.) is deployed on the satellite, which is called the satellite base station; the core network (EPC, 5GC, etc.) is deployed on the ground. Of course, some core network elements can also be deployed on the satellite as shown in Figure 3. In the embodiment shown in Figure 4, the core network is connected to the application server, and the satellite base station is connected to another satellite via an inter-satellite link (ISL). When the UE needs to communicate with the application server, it is necessary to establish a communication connection with the core network based on the inter-satellite link between the satellite base station and another satellite, and the feedback link between the other satellite and the gateway, and then realize the communication interaction with the application server based on the core network.

[0045] It should be noted that, although FIG4 only shows the ISL between two satellites, the embodiment of the present application is not limited thereto, and the UE may communicate with the application server through multiple ISLs between multiple satellites.

[0046] In some embodiments, the UE in the above embodiments may be a smart phone, a tablet computer, a laptop computer, a desktop computer, a smart TV, a smart home, a vehicle terminal, an aircraft, etc. The application server may be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, content delivery networks (CDNs), and big data and artificial intelligence platforms.

[0047] In the network architecture shown in Figures 2 to 4, due to the movement of the satellite, the service link or feedback link may become unavailable. Even if the application end can obtain the availability of the feedback link by interacting with the core network, it is difficult to obtain the availability of the service link. As a result, the application end cannot perceive the availability of the service link, which affects the data transmission efficiency. Based on this, the embodiment of the present application proposes a new satellite-based communication solution, which enables the application end to perceive the availability information of the service link, and then transmit service data to the user equipment based on the availability information of the service link. This avoids the problem of low data transmission efficiency caused by the application end transmitting service data when the service link is unavailable, realizes intelligent transmission of service data, is conducive to improving data transmission efficiency, and reduces the processing load of the base station.

[0048] The following is a detailed description of the implementation details of the technical solution of the embodiment of the present application:

[0049] FIG5 shows a flow chart of a satellite-based communication method according to some embodiments of the present application. The satellite is deployed with at least an onboard base station, and a service link is established between the onboard base station and the user equipment. The satellite-based communication method can be executed by a core network element, such as an access and mobility management function (AMF), or by other network elements capable of implementing similar functions. Referring to FIG5 , the satellite-based communication method includes at least S510 to S530, which are described in detail as follows:

[0050] In S510, availability information of a service link between a satellite-borne base station and a user equipment is obtained.

[0051] In the embodiments of this application, a satellite-borne base station refers to a base station deployed on a satellite. In addition to performing base station functions in a mobile communication system, the base station can also move with the satellite. The satellite-borne base station can be an eNB in ​​a 4G system, a gNB in ​​a 5G system, or a base station device in a future evolved mobile communication system.

[0052] In some embodiments, as shown in Figures 2 to 4, the satellite-borne base station needs to establish a service link with the user equipment and a feedback link with the gateway, and the gateway is connected to the core network element in the core network. In some embodiments, the satellite-borne base station may first establish a communication link with the gateway, and then send a connection establishment request to the core network element via the established communication link. If the satellite-borne base station receives a connection establishment response from the core network element in response to the connection establishment request, it can be determined that the communication connection between the satellite-borne base station and the core network element is successfully established.

[0053] In some embodiments, if the satellite base station is an eNB in ​​a 4G system, the connection establishment request sent by the satellite base station may be an S1 establishment request; if the satellite base station is a gNB in ​​a 5G system, the connection establishment request sent by the satellite base station may be an NG establishment request.

[0054] In some embodiments, the connection establishment request sent by the satellite base station to the core network network element may include at least one of the following information: information on the service link between the satellite base station and the user equipment, information on the communication link between the satellite base station and the gateway, location information of the satellite base station, ephemeris information of the satellite base station (wherein ephemeris information refers to the precise position or trajectory table that changes with time when the satellite base station is running, which is a function of time), and network address information of the satellite base station.

[0055] It should be noted that the gateway between the satellite base station and the core network element can be a gateway deployed on the ground (i.e., a ground gateway), or it can be a general term for gateways deployed on satellites (i.e., satellite gateways) and gateways deployed on the ground (i.e., ground gateways). It can also be other equipment that can realize the connection between the satellite base station and the core network.

[0056] In some embodiments, the core network element may determine the availability information of the service link based on at least one of the following information: ephemeris information of the satellite base station, subscription information of the user equipment, and interaction information between the user equipment and the satellite base station.

[0057] In some embodiments, the ephemeris information of a satellite base station refers to a precise position or trajectory table that changes over time during the operation of the satellite base station, which is a function of time. For example, a core network element may obtain the ephemeris information of the satellite base station in advance and then determine, based on the precise position or trajectory table that changes over time during the movement, that the satellite base station is about to move to a new position and needs to disconnect from the user equipment at this new position, resulting in a service link unavailability situation.

[0058] In some embodiments, the core network element determines the availability information of the service link based on the subscription information of the user equipment, which can be determined based on one or more of the available time period information, priority information, total amount of data traffic used, etc. of the subscription of the user equipment. For example, if it is determined based on the subscription information of the user equipment that the user equipment cannot use the satellite communication function within a certain time period, then it can be determined that the service link of the user equipment is unavailable within this time period; for another example, if it is determined based on the subscription information of the user equipment that the total amount of data traffic used by the user equipment reaches a set threshold and the satellite communication function can no longer be used, then when the total amount of data traffic used by the user equipment reaches the set threshold, it can be determined that the service link of the user equipment is unavailable; for another example, if it is determined based on the subscription information of the user equipment that the priority of the user equipment is low, then when there are many user equipment using the satellite communication function in the same area, it can be determined that the service link of the user equipment is unavailable to reduce the impact on the communication of other user equipment.

[0059] In some embodiments, the interaction information between the user equipment and the satellite base station refers to the actual interaction between the user equipment and the satellite base station. For example, the user equipment registers in the core network element by interacting with the satellite base station and forms context information, which means that the service link corresponding to the user equipment is in an available state.

[0060] In some embodiments, the availability information of the service link includes at least one of the following: real-time availability information and availability information within a future set time period. In some embodiments, the real-time availability information refers to the availability information of the service link within the current time period (e.g., 10 seconds, 1 minute, 3 minutes, etc. starting from the current time point); the availability information within the future set time period refers to the availability information of the service link within a certain time period in the future (e.g., 10 seconds, 1 minute, 3 minutes, etc. starting from a certain moment).

[0061] In some embodiments, the availability information of the service link is used to indicate: whether the service link is available, and / or the reliability, stability and reachability of the service link. Availability information may refer to whether the service link is available, or may refer to information such as the reliability, stability and reachability of the service link. Reliability refers to the ability of the service link to complete the specified functions within the specified time and conditions; whether it can provide long-lasting and stable services and is not prone to failures or errors. Stability refers to the failure rate, crash rate and recovery capability of the service link during operation; whether the service link can continue to provide stable service quality without frequent failures or interruptions. Reachability refers to whether the service link can be successfully accessed from the user device side, including network connectivity, load balancing and other aspects; whether each component and link of the service link can be successfully accessed by the user device without obstruction or restriction.

[0062] In S520, the availability information of the service link is made available to the application function entity.

[0063] In some embodiments, the core network element may also receive a request message from an application function entity, requesting availability information for a service link. The core network element then sends the service link availability information to the application function entity in response to the request message. That is, in this embodiment, the core network element may obtain the service link availability information after receiving the request message from the application function entity and then make the information available to the application function entity. Alternatively, the core network element may receive a subscription request from the application function entity and, after returning a subscription response to the application function entity, obtain (e.g., periodically or continuously) the service link availability information based on the subscription request and make the obtained service link availability information available to the application function entity. In some embodiments, the core network element may also periodically or continuously obtain the service link availability information and then, after receiving the request message from the application function entity, make the service link availability information available to the application function entity. In other embodiments of the present application, after obtaining the service link availability information, the core network element may also proactively make the service link availability information available to the application function entity, without waiting for a request message from the application function entity.

[0064] In some embodiments, if the communication method shown in Figure 5 is executed by a core network element deployed on a satellite, and the application function entity is deployed on the satellite, then since the core network element on the satellite and the application function entity on the satellite are both on the satellite and are not affected by the interruption of the communication link between the satellite and the ground gateway, the core network element deployed on the satellite can directly send the availability information of the service link to the application function entity through the communication connection between the core network element and the application function entity.

[0065] In some embodiments, if the communication method shown in FIG5 is performed by a first core network element deployed on a satellite, the first core network element establishes a communication connection with a second core network element deployed on the ground through a gateway, and the application function entity is deployed on the ground, then the process of the first core network element deployed on the satellite providing the availability information of the service link to the application function entity may specifically be: if the communication link between the first core network element and the gateway (the communication link may be referred to as a feedback link) is available, the first core network element may send the availability information of the service link to the second core network element via the communication link, so that the second core network element forwards the availability information to the application function entity.

[0066] The technical solution of this embodiment is applied to application scenarios in which some core network elements are deployed on satellites and some are deployed on the ground. In this scenario, due to the movement of the satellite, the communication link between the first core network element and the gateway may be interrupted. Therefore, when the communication link between the first core network element and the gateway is available, the availability information of the service link is sent to the second core network element through the communication link, so that the second core network element can forward it to the application function entity.

[0067] In some embodiments, if the communication link between the first core network element and the gateway is unavailable when the first core network element opens the availability information of the service link to the application function entity, the first core network element may first cache the availability information of the service link and set a timer. Before the timer exceeds the set duration, if the communication link between the first core network element and the gateway changes from unavailable to available, the availability information of the service link is sent to the second core network element, so that the second core network element forwards the availability information to the application function entity.

[0068] In some embodiments, if the communication link between a first core network element deployed on a satellite and a gateway remains unavailable within a set duration after obtaining availability information of a service link, then a determination can be made that the service link availability information feedback has timed out. In some embodiments, since satellite movement may cause interruptions in the feedback link (i.e., the communication link between the first core network element and the gateway), the communication interruption duration of the communication link between the first core network element and the gateway can be inferred based on the satellite's ephemeris information, and the set duration can then be set to be greater than or equal to the communication interruption duration. This avoids premature determination of availability information feedback timeout due to a short set duration.

[0069] In other embodiments of the present application, when determining the size of the set duration, in addition to considering the communication interruption time of the communication link between the first core network network element and the gateway, the information propagation delay can also be considered. For example, the information propagation delay of the communication link between the first core network network element and the gateway can be inferred (or the information propagation delay of the communication link between the first core network network element and the second core network network element), and then the set duration is made greater than or equal to the sum of the communication interruption time and the information propagation delay. This can also avoid premature determination of availability information feedback timeout due to a short set duration.

[0070] In some embodiments, if it is determined that the feedback of the availability information of the service link has timed out, the first core network element deployed on the satellite may discard the obtained availability information, and then re-acquire it and re-determine whether the communication link between the first core network element and the gateway is available, until the availability information is sent to the application function entity, or the number of retries or the waiting time reaches a set threshold. Of course, in other embodiments of the present application, if it is determined that the feedback of the availability information of the service link has timed out, the obtained availability information may be directly discarded and no retries are performed; or it may be saved until it can be sent to the application function entity.

[0071] In some embodiments, if the communication method shown in FIG5 is performed by a second core network element deployed on the ground, and the application function entity is also deployed on the ground, then when the second core network element deployed on the ground obtains the availability information of the service link between the satellite base station and the user equipment, it can receive the service link availability information sent by the satellite base station or the first core network element deployed on the satellite. The satellite base station or the first core network element deployed on the satellite establishes a communication link with the core network element deployed on the ground through a gateway.

[0072] In some embodiments, obtaining the availability information of the service link between the satellite base station and the user equipment includes: when the communication link between the gateway and the second core network element is available, receiving the availability information of the service link sent by the satellite base station or the first core network element deployed on the satellite through the communication link.

[0073] In some embodiments, when the communication link between the gateway and the second core network element is unavailable, the method further comprises: buffering a request message sent by the application function entity for requesting availability information of the service link, and setting a timer;

[0074] Before the timing duration of the timer exceeds the set duration, if the availability information of the service link sent by the onboard base station or the first core network element deployed on the satellite is received through the communication link, the availability information of the service link is sent to the application function entity.

[0075] In some embodiments, if the second core network element deployed on the ground does not obtain the availability information of the service link within a set time period after receiving the request message sent by the application function entity, then it can be determined that the availability information feedback of the service link has timed out. In some embodiments, if it is determined that the availability information feedback of the service link has timed out, the second core network element deployed on the ground can continue to wait until the availability information of the service link is obtained, or it can stop waiting. In some embodiments, since the feedback link (i.e., the communication link between the onboard base station or the first core network element deployed on the satellite and the gateway) is interrupted when the satellite moves, the communication interruption time of the communication link between the onboard base station or the first core network element deployed on the satellite and the gateway can be inferred based on the satellite's ephemeris information, and then the set time period is made greater than or equal to the communication interruption time, so as to avoid premature determination of the availability information feedback timeout due to a short set time period.

[0076] In other embodiments of the present application, when determining the size of the set duration, in addition to considering the communication interruption time of the communication link between the satellite base station or the first core network element deployed on the satellite and the gateway, the information propagation delay can also be considered. For example, the information propagation delay of the communication link between the satellite base station or the first core network element deployed on the satellite and the gateway can be inferred (or it can be the information propagation delay of the communication link between the satellite base station or the first core network element deployed on the satellite and the second core network element deployed on the ground), and then the set duration is made greater than or equal to the sum of the communication interruption time and the information propagation delay. This can also avoid premature determination of availability information feedback timeout due to a short set duration.

[0077] FIG5 illustrates the technical solution of the embodiment of the present application from the perspective of a core network element. The following describes the implementation details of the technical solution of the present application from the perspective of an application function entity in conjunction with FIG6 .

[0078] FIG6 shows a flow chart of a satellite-based communication method according to some embodiments of the present application. The satellite is deployed with at least an onboard base station, and a service link is established between the onboard base station and the user equipment. The satellite-based communication method can be executed by an application function entity or by other devices capable of performing similar functions. Referring to FIG6 , the satellite-based communication method includes at least S610 to S620, which are described in detail as follows:

[0079] In S610, availability information of a service link sent by a core network element is received, where the service link is a communication link established between a satellite base station and a user equipment.

[0080] In some embodiments, before receiving the availability information of the service link sent by the core network network element, the application function entity may also generate a request message, which is used to request to obtain the availability information of the service link, and then send the request message to the core network network element to request the core network network element to open the availability information of the service link.

[0081] In some embodiments, the description of the availability information of the service link can refer to the technical solutions of the aforementioned embodiments and will not be repeated here.

[0082] In S620, data is sent to the user equipment via the service link according to the availability information of the service link.

[0083] In some embodiments, sending data to the user equipment through the service link based on the availability information of the service link may include sending data to the user equipment through the service link when the service link is available, or sending data to the user equipment through the service link when the communication quality of the service link is good (for example, the communication quality meets a predetermined condition). The data sent to the user equipment may be user plane data or control plane data.

[0084] In some embodiments, the sending data to the user equipment through the service link according to the availability information of the service link includes:

[0085] If it is determined according to the availability information of the service link that the service link is available, sending data to the user equipment through the service link; or

[0086] If it is determined according to the availability information of the service link that the communication quality of the service link meets a predetermined condition, data is sent to the user equipment through the service link.

[0087] The technical solution of the above-mentioned embodiment of the present application opens the availability information of the service link to the application function entity, so that the application function entity can perceive the availability information of the service link, and then transmit business data to the user equipment according to the availability information of the service link, thereby avoiding the problem of low data transmission efficiency caused by the application function entity transmitting business data when the service link is unavailable, realizing intelligent transmission of business data, which is conducive to improving data transmission efficiency and reducing base station processing load.

[0088] The above describes the technical solutions of the embodiments of the present application from the perspectives of the core network element and the application function entity. The implementation details of the technical solutions of the embodiments of the present application are described in detail below with reference to Figures 7 to 10:

[0089] The technical solution of the embodiments of this application primarily addresses the possibility that service links may become unavailable due to satellite movement. Core network elements can expose service link availability information to the AF, enabling the AF to perceive service link availability information, thereby enabling more intelligent service data transmission and reducing base station processing load. Corresponding solutions are also proposed for application scenarios in which core network functions are deployed on satellites and on the ground.

[0090] Specifically, in an application scenario of the present application, as shown in Figure 7, the base station is deployed on a satellite to form a satellite base station. The satellite base station can move with the satellite. In this case, the UE may be connected to different satellite base stations, and the satellite base stations may also be connected to different ground gateways (in some embodiments, a gateway connected to the satellite base station may also be deployed on the satellite, and the gateway can communicate with the ground gateway to achieve a connection between the satellite base station and the ground gateway). A service link is formed between the UE and the satellite base station, and a feedback link is formed between the satellite base station and the ground gateway. If the satellite where the satellite base station is located is not ground-synchronized, the satellite base station may be connected to different ground gateways at different locations, and when the satellite periodically returns to a certain position, the satellite base station will still be connected to the same ground gateway again.

[0091] In some embodiments, if the satellite base station is an eNB in ​​a 4G system, the satellite base station can establish a connection with the MME in the EPC, or it can also establish a connection with other network elements in the EPC; if the satellite base station is a gNB in ​​a 5G system, the satellite base station can establish a connection with the AMF in the 5GC, or it can also establish a connection with other network elements in the 5GC. In some embodiments, the gateway can be a gateway deployed on the ground for communicating with the satellite base station, such as an NTN-GW or other gateway.

[0092] As shown in Figure 7, in addition to onboard base stations, some core network functions can also be deployed on the satellite. For ease of description, the core network elements on the satellite are referred to as onboard core network elements. An onboard AF can also be deployed on the satellite. In this case, the UE and the onboard AF can still communicate on the cellular network even if the feedback link is unavailable.

[0093] In some embodiments of the present application, if the availability information of the service link needs to be exposed to the onboard AF, the onboard core network element can directly expose the availability information of the service link to the onboard AF. In some embodiments, this application scenario requires the onboard core network element to support network information exposure, and the network information exposure can be implemented through the user plane or the control plane.

[0094] In some embodiments, if the onboard core network element is an onboard 5GC network element, then the onboard 5GC network element may be an AMF or other network element capable of realizing network information openness. If the onboard core network element is an onboard EPC network element, then the onboard EPC network element may be a Service Capability Exposure Function (SCEF) network element.

[0095] In some embodiments, opening network information through the control plane can reduce the logical processing functions of the core network elements on board the satellite. For example, taking the 5G system as an example, when the availability information of the service link is opened to the AF from the base station perspective, the specific opening path can be gNB-AMF-Session Management Function (SMF)-Policy Control Function (PCF)-Network Exposure Function (NEF)-AF (that is, the gNB sends the availability information of the service link to the AMF, the AMF forwards it to the SMF, the SMF sends the availability information of the service link to the PCF, the PCF sends the availability information to the NEF, and the NEF sends the availability information to the AF). Some of the network elements are optional, such as the NEF can be omitted; or the AMF can replace the gNB as the sending node of the service link availability information and transparently forward the availability information to the AF. For this embodiment, taking the 5G system as an example, the signaling process of opening the availability of the service link is shown in Figure 8, including the following steps:

[0096] S801: The onboard AF subscribes to or requests availability information of a service link. In some embodiments, the onboard AF may request the core network element to open the availability information of the service link via the AF-NEF-PCF-SMF-AMF. The NEF transmission process is not required and may be omitted.

[0097] In some embodiments, the AF may send a subscription request for the availability information of the service link to the AMF through the NEF, PCF, and SMF, and then the AMF may return subscription response information to the AF through the SMF, PCF, and NEF.

[0098] In some embodiments, the AF may send a request message to the AMF through the NEF, PCF, and SMF to request the availability information of the service link, and then the AMF returns the availability information of the service link to the AF through the SMF, PCF, and NEF.

[0099] In some embodiments, the AMF may obtain service link availability information from the N2 interface between the AMF and the gNB. It should be noted that, in the embodiments of the present application, service link availability information may be determined by inferring ephemeris information, or may be obtained by verification via the Uu interface. For example, through the actual operation of the Uu interface, some UEs may actually access the base station and register with the AMF to form context information, thereby determining that the service link is available. Of course, service link availability information may also be obtained by other methods described in the aforementioned embodiments.

[0100] S802, AMF opens the availability information of the service link to the onboard AF.

[0101] In some embodiments, the availability information of the service link may be real-time availability information, or availability information within a future period of time, for example, availability information within the next month or day.

[0102] In some embodiments of the present application, if the availability information of the service link needs to be opened to the ground AF, then the core network elements may be located entirely on the ground; or they may be located partially on the ground and partially on the satellite. Therefore, the opening of network information depends on the availability of the feedback link. In other words, network information opening can only be carried out during the time period when the feedback link is available. At the same time, the interaction cycle of network information opening needs to be lengthened. When the AF initiates a subscription or request for network information opening, the AMF needs to set a reasonable timing duration for the timer to avoid a long waiting time for the signaling of network information opening due to a long feedback link disconnection time. For the embodiment in which all core network elements are located on the ground, taking the 5G system as an example, the signaling process for opening the availability of the service link is shown in Figure 9, which includes the following steps:

[0103] S901: The ground AF subscribes to or requests availability information of a service link. In some embodiments, the ground AF can request the core network element to open the availability information of the service link via the AF-NEF-PCF-SMF-AMF. The NEF transmission process is not required and can be omitted.

[0104] In some embodiments, the AF may send a subscription request for the availability information of the service link to the AMF through the NEF, PCF, and SMF, and then the AMF may return subscription response information to the AF through the SMF, PCF, and NEF.

[0105] In some embodiments, the AF may send a request message to the AMF through the NEF, PCF, and SMF to request the availability information of the service link, and then the AMF returns the availability information of the service link to the AF through the SMF, PCF, and NEF.

[0106] In some embodiments, the AMF may obtain service link availability information from the N2 interface between the AMF and the gNB. It should be noted that, in the embodiments of the present application, service link availability information may be determined by inferring ephemeris information, or may be obtained by verification via the Uu interface. For example, through the actual operation of the Uu interface, some UEs may actually access the base station and register with the AMF to form context information, thereby determining that the service link is available. Of course, service link availability information may also be obtained by other methods described in the aforementioned embodiments.

[0107] S902: Set a timer and make a judgment. If the AMF does not obtain the availability information of the service link after waiting for a set time period after receiving a subscription request or acquisition request sent by the ground AF (possibly due to a feedback link interruption), it can be determined that the availability information feedback has timed out.

[0108] In some embodiments, if the feedback link is available, the AMF can obtain the availability information of the service link through the feedback link; if the feedback link is unavailable, the AMF caches the request message sent by the ground AF and sets a timer; if the feedback link becomes available from unavailable before the timer exceeds the set time, the AMF can obtain the availability information of the service link through the feedback link; if the timer exceeds the set time and the feedback link is still unavailable, it can be determined that the availability information feedback has timed out.

[0109] In some embodiments, if it is determined that the availability information feedback has timed out, the AMF may continue to wait until availability information of the service link is obtained, or may not wait any longer. In some embodiments, since the feedback link may be interrupted when the satellite moves, the communication interruption time of the feedback link can be inferred based on the satellite's ephemeris information, and the preset duration can be set to be greater than or equal to the communication interruption time. This can avoid premature determination of availability information feedback timeout due to a short preset duration.

[0110] In other embodiments of the present application, when determining the size of the preset duration, in addition to considering the communication interruption time of the feedback link, the information propagation delay may also be considered. For example, the information propagation delay of the feedback link may be inferred, and then the preset duration may be made greater than or equal to the sum of the communication interruption time and the information propagation delay. This can also avoid premature determination of availability information feedback timeout due to a short preset duration.

[0111] S903, AMF opens the availability information of the service link to the onboard AF.

[0112] In some embodiments, the availability information of the service link may be real-time availability information, or availability information within a future period of time, for example, availability information within the next month or day.

[0113] In some embodiments of the present application, for an embodiment in which core network elements are partially located on the ground and partially located on a satellite, taking a 5G system as an example, the signaling process for opening the availability of a service link is shown in FIG10 , including the following steps:

[0114] S1001: The ground AF subscribes to or requests availability information for a service link. In some embodiments, the ground AF may request availability information for a core network element's open service link via an AF-NEF-PCF-SMF-AMF message (specifically, sent to the ground-based AMF, i.e., AMF-G). The NEF transmission process is optional and can be omitted.

[0115] In some embodiments, the AF may send a subscription request for the availability information of the service link to the AMF through the NEF, PCF, and SMF, and then the AMF may return subscription response information to the AF through the SMF, PCF, and NEF.

[0116] In some embodiments, the AF may send a request message to the AMF through the NEF, PCF, and SMF to request the availability information of the service link, and then the AMF returns the availability information of the service link to the AF through the SMF, PCF, and NEF.

[0117] It should be noted that, in the embodiment shown in FIG10 , an example is given in which the AMF is partially deployed on the ground (ie, AMF-G) and partially deployed on the satellite (ie, AMF-S).

[0118] In some embodiments, the AMF-G may interact with the AMF-S to obtain service link availability information. The AMF-G sends a subscription request for service link availability information or a request message to the AMF-S to obtain service link availability information. The AMF-S sends the obtained service link availability information to the AMF-G via a feedback link. The AMF-S may obtain the service link availability information via the N2 interface between the AMF-S and the gNB. It should be noted that in the embodiments of the present application, the service link availability information may be determined by inferring ephemeris information or by verifying it via the Uu interface. For example, through actual operation of the Uu interface, some UEs may actually access the base station and register with the AMF (which may be at least one of the AMF-S and AMF-G) to form context information, thereby confirming that the service link is available. Of course, the service link availability information may also be obtained through other methods described in the aforementioned embodiments.

[0119] S1002, AMF sets a timer and makes a judgment.

[0120] In some embodiments, after receiving a subscription request or a retrieval request from a ground AF, the AMF-G caches the request and starts a timer. If the waiting time exceeds a set time and the availability information of the service link is still not obtained (possibly due to a feedback link interruption), it can be determined that the availability information feedback has timed out. If it is determined that the availability information feedback has timed out, the AMF-G can continue to wait until the availability information of the service link is obtained, or it can stop waiting.

[0121] In some embodiments, the AMF-S may start a timer after obtaining the availability information of the service link or after receiving a request sent by the AMF-G. If the waiting time exceeds a set time (which may be the same as or different from the set time of the AMF-G timer) and the availability information of the service link cannot be sent to the AMF-G (possibly due to the interruption of the feedback link), it can be determined that the availability information feedback has timed out. If it is determined that the availability information feedback has timed out, the AMF-S may discard the obtained availability information and then re-acquire it until the availability information is sent to the AMF-G; or until the number of retries or the waiting time reaches a set threshold; or if the AMF-S determines that the availability information feedback of the service link has timed out, it may directly discard the obtained availability information and no longer retry; or it may save it until it can be sent to the AMF-G.

[0122] In some embodiments, since the feedback link may be interrupted when the satellite moves, the communication interruption time of the feedback link (i.e., the communication link between the satellite and the gateway, which in this embodiment can be the communication link between the AMF-S and the gateway, and of course, the communication link between the AMF-S and the AMF-G) can be inferred based on the satellite's ephemeris information, and then the set duration is made greater than or equal to the communication interruption time. This can avoid premature determination of availability information feedback timeout due to a short set duration.

[0123] In other embodiments of the present application, when determining the set duration, in addition to considering the communication interruption time of the feedback link, the information propagation delay may also be considered. For example, the information propagation delay of the feedback link may be inferred, and then the set duration may be made greater than or equal to the sum of the communication interruption time and the information propagation delay. This may also avoid premature determination of availability information feedback timeout due to a short set duration.

[0124] S1003, AMF-S opens the availability information of the service link to the onboard AF.

[0125] In some embodiments, the availability information of the service link may be real-time availability information, or availability information within a future period of time, for example, availability information within the next month or day.

[0126] It is worth noting that in the above embodiments of the present application, the 5G system is used as an example for description. In other embodiments of the present application, it can also be applied to the 4G system and future evolved mobile communication systems.

[0127] The technical solution of the embodiment of the present application enables the core network element to open the availability information of the service link to the AF, and then the AF can perceive the availability information of the service link, thereby transmitting business data more intelligently, which is conducive to improving data transmission efficiency.

[0128] The following describes an apparatus embodiment of the present application, which can be used to perform the satellite-based communication method described in the above-mentioned embodiments of the present application. For details not disclosed in the apparatus embodiment of the present application, please refer to the above-mentioned embodiment of the satellite-based communication method of the present application.

[0129] Figure 11 shows a block diagram of a satellite-based communication device according to some embodiments of the present application, where at least a satellite-borne base station is deployed on the satellite, and a service link is established between the satellite-borne base station and the user equipment. The satellite-based communication device is applied to a core network element, such as an AMF, or can also be applied to other network elements that can implement similar functions.

[0130] 11 , a satellite-based communication device 1100 according to some embodiments of the present application is applied to a core network element and includes: an acquiring unit 1102 and a sending unit 1104 .

[0131] Among them, the acquisition unit 1102 is configured to obtain the availability information of the service link between the satellite base station and the user equipment; the sending unit 1104 is configured to open the availability information of the service link to the application function entity, wherein the availability information of the service link serves as the basis for the application function entity to send data to the user equipment through the satellite base station.

[0132] In some embodiments of the present application, based on the aforementioned scheme, the communication device 1100 also includes: a receiving unit, configured to receive a request message sent by the application function entity, the request message being used to request the availability information of the service link; the sending unit 1104 is configured to: send the availability information of the service link to the application function entity in response to the request message.

[0133] In some embodiments of the present application, based on the aforementioned scheme, the core network network element is deployed on the satellite, and the application function entity is deployed on the satellite; the sending unit 1104 is configured to: send the availability information of the service link to the application function entity through the communication connection between the core network network element and the application function entity.

[0134] In some embodiments of the present application, based on the aforementioned solution, the core network element is a first core network element deployed on the satellite, the application function entity is deployed on the ground, and the first core network element establishes a communication link with a second core network element deployed on the ground through a gateway;

[0135] The sending unit 1104 is configured to: when the communication link between the first core network network element and the gateway is available, send the availability information of the service link to the second core network network element through the communication link, so that the second core network network element forwards the availability information to the application function entity.

[0136] In some embodiments of the present application, based on the above solution, the sending unit 1104 is further configured to:

[0137] When the communication link between the first core network element and the gateway is unavailable, cache the availability information of the service link and set a first timer;

[0138] Before the first timer exceeds a first set duration, if the communication link between the first core network element and the gateway changes from unavailable to available, sending the availability information of the service link to the second core network element, so that the second core network element forwards the availability information to the application function entity;

[0139] Before the first timer exceeds a first set duration, if the communication link between the first core network element and the gateway is unavailable, it is determined that the availability information feedback of the service link has timed out.

[0140] In some embodiments of the present application, based on the aforementioned solution, the first set duration is greater than or equal to the predicted communication interruption time of the communication link; or the first set duration is greater than or equal to the sum of the predicted communication interruption time and the communication propagation delay of the communication link;

[0141] The predicted communication interruption time of the communication link is determined based on the ephemeris information of the satellite.

[0142] In some embodiments of the present application, based on the aforementioned scheme, the core network network element is a second core network network element deployed on the ground, and the application function entity is deployed on the ground; wherein, the satellite base station or the first core network network element deployed on the satellite establishes a communication link with the second core network network element deployed on the ground through a gateway; the acquisition unit 1102 is configured to: when the communication link between the gateway and the second core network network element is available, receive the availability information of the service link sent by the satellite base station or the first core network network element deployed on the satellite through the communication link.

[0143] In some embodiments of the present application, based on the above solution, the acquiring unit 1102 is further configured to:

[0144] caching a request message sent by the application function entity for requesting to obtain the availability information of the service link, and setting a second timer;

[0145] Before the timing of the second timer exceeds a second set duration, if the availability information of the service link sent by the onboard base station or the first core network element deployed on the satellite is received through the communication link, the availability information of the service link is sent to the application function entity;

[0146] If the availability information of the service link is not obtained before the second timer exceeds the second set duration, it is determined that the feedback of the availability information of the service link has timed out.

[0147] In some embodiments of the present application, based on the foregoing solution, the second set duration is greater than or equal to the predicted communication interruption time of the communication link between the onboard base station or the core network element deployed on the satellite and the gateway; or the second set duration is greater than or equal to the sum of the predicted communication interruption time and the communication propagation delay of the communication link;

[0148] The predicted communication interruption time of the communication link is determined based on the ephemeris information of the satellite.

[0149] In some embodiments of the present application, based on the aforementioned solution, the availability information of the service link includes at least one of the following: real-time availability information, and availability information within a future set time period.

[0150] In some embodiments of the present application, based on the aforementioned scheme, the acquisition unit 1102 is configured to determine the availability information of the service link based on at least one of the following information: the ephemeris information of the satellite base station, the contract information of the user equipment, and the interaction information between the user equipment and the satellite base station.

[0151] Figure 12 shows a block diagram of a satellite-based communication device according to some embodiments of the present application, where at least a satellite-borne base station is deployed on the satellite, and a service link is established between the satellite-borne base station and the user equipment. The satellite-based communication device is applied to an application functional entity, or can also be applied to other network elements that can implement similar functions.

[0152] 12 , a satellite-based communication device 1200 according to some embodiments of the present application includes a receiving unit 1202 and a processing unit 1204 .

[0153] Among them, the receiving unit 1202 is configured to receive availability information of the service link sent by the core network network element, where the service link is a communication link established between the satellite base station and the user equipment; the processing unit 1204 is configured to send data to the user equipment through the service link according to the availability information of the service link.

[0154] In some embodiments, the processing unit 1204 is further configured to:

[0155] If it is determined according to the availability information of the service link that the service link is available, sending data to the user equipment through the service link; or

[0156] If it is determined according to the availability information of the service link that the communication quality of the service link meets a predetermined condition, data is sent to the user equipment through the service link.

[0157] In some embodiments of the present application, based on the aforementioned scheme, the communication device 1200 also includes: a generating unit, configured to generate a request message before receiving the availability information of the service link sent by the core network network element, wherein the request message is used to request to obtain the availability information of the service link; and a sending unit, configured to send the request message to the core network network element.

[0158] Figure 13 shows a structural diagram of a computer system of an electronic device suitable for implementing an embodiment of the present application. The electronic device may be a core network element or an application function entity in the aforementioned embodiment.

[0159] It should be noted that the computer system 1300 of the electronic device shown in FIG13 is merely an example and should not impose any limitations on the functions and scope of use of the embodiments of the present application.

[0160] As shown in Figure 13, the computer system 1300 may include a central processing unit (CPU) 1301, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 1302 or the program loaded from the storage part 1308 into the random access memory (RAM) 1303, such as executing the method described in the above embodiment. Various programs and data required for system operation are also stored in the RAM 1303. The CPU 1301, ROM 1302 and RAM 1303 are connected to each other via a bus 1304. An input / output (I / O) interface 1305 is also connected to the bus 1304.

[0161] The following components can be connected to the I / O interface 1305: an input section 1306 including a keyboard, mouse, etc.; an output section 1307 including devices such as a cathode ray tube (CRT), a liquid crystal display (LCD), and speakers; a storage section 1308 including a hard disk; and a communication section 1309 including a network interface card such as a LAN (Local Area Network) card or a modem. The communication section 1309 performs communication processing via a network such as the Internet. A drive 1310 is also connected to the I / O interface 1305 as needed. Removable media 1311, such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, is installed in the drive 1310 as needed, so that computer programs read from the removable media can be installed in the storage section 1308 as needed.

[0162] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program is used to perform the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via the communication section 1309, and / or installed from a removable medium 1311. When the computer program is executed by the central processing unit (CPU) 1301, the various functions defined in the system of the present application are performed.

[0163] It should be noted that the computer-readable medium shown in the embodiments of the present application may be a computer-readable signal medium or a computer-readable storage medium or any combination of the two. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium containing or storing a computer program that can be used by or in combination with an instruction execution system, device or device. In the present application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries a computer-readable computer program. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can transmit, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. A computer program embodied on a computer-readable medium may be transmitted using any suitable medium, including but not limited to wireless, wired, or any suitable combination thereof.

[0164] The flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present application. Among them, each box in the flowchart or block diagram can represent a module, program segment, or a part of the code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and a computer program.

[0165] The units involved in the embodiments described in this application may be implemented by software or hardware, and the units described may also be set in a processor. In some cases, the names of these units do not constitute limitations on the units themselves.

[0166] As another aspect, the present application further provides a computer-readable medium, which may be included in the electronic device described in the above embodiments, or may exist independently without being incorporated into the electronic device. The computer-readable medium carries one or more computer programs, and when the one or more computer programs are executed by the electronic device, the electronic device implements the method described in the above embodiments.

[0167] It should be noted that, although several modules or units of the device for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiment of the application, the features and functions of two or more modules or units described above can be concretized in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into multiple modules or units to be concretized.

[0168] Through the description of the above embodiments, it is easy for those skilled in the art to understand that the example embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solution according to the embodiments of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, and includes several instructions to enable an electronic device to execute the method according to the embodiments of the present application.

[0169] For example, the electronic device may be a core network element, and the core network element may execute the communication method shown in FIG5 ; for another example, the electronic device may be an application function entity, and the application function entity may execute the communication method shown in FIG6 .

[0170] Those skilled in the art will readily conceive of other embodiments of the present application after considering the specification and practicing the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of this application and include common knowledge or customary techniques in the art that are not disclosed herein.

[0171] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A satellite-based communication method, executed by a core network element, wherein the satellite has at least an onboard base station deployed thereon, the communication method comprising: Acquiring availability information of a service link between the satellite-borne base station and the user equipment; The availability information of the service link is opened to an application function entity, wherein the availability information of the service link serves as a basis for the application function entity to send data to the user equipment through the satellite-borne base station.

2. The satellite-based communication method according to claim 1, wherein: The availability information of the service link is used to indicate whether the service link is available and / or the reliability, stability and reachability of the service link.

3. The satellite-based communication method according to claim 1 or 2, further comprising: receiving a request message sent by the application function entity, where the request message is used to request availability information of the service link; The opening of the availability information of the service link to the application function entity includes: sending the availability information of the service link to the application function entity in response to the request message.

4. The satellite-based communication method according to any one of claims 1 to 3, wherein: The core network element and the application function entity are both deployed on the satellite; The opening of the availability information of the service link to the application function entity includes: sending the availability information of the service link to the application function entity through the communication connection between the core network element and the application function entity.

5. The satellite-based communication method according to any one of claims 1 to 3, wherein: The core network element is a first core network element deployed on the satellite, the application function entity is deployed on the ground, and the first core network element establishes a communication link with a second core network element deployed on the ground through a gateway; The opening of the availability information of the service link to the application function entity includes: When the communication link between the first core network element and the gateway is available, the availability information of the service link is sent to the second core network element through the communication link, so that the second core network element forwards the availability information to the application function entity.

6. The satellite-based communication method of claim 5, further comprising: When the communication link between the first core network element and the gateway is unavailable, cache the availability information of the service link and set a first timer; Before the first timer exceeds a first set duration, if the communication link between the first core network element and the gateway changes from unavailable to available, sending the availability information of the service link to the second core network element, so that the second core network element forwards the availability information to the application function entity; Before the first timer exceeds a first set duration, if the communication link between the first core network element and the gateway is unavailable, it is determined that the availability information feedback of the service link has timed out.

7. The satellite-based communication method according to claim 6, wherein: The first set duration is greater than or equal to the predicted communication interruption time of the communication link; or The first set duration is greater than or equal to the sum of the predicted communication interruption time and the communication propagation delay of the communication link; The predicted communication interruption time of the communication link is determined based on the ephemeris information of the satellite.

8. The satellite-based communication method according to any one of claims 1 to 3, wherein: The core network element is a second core network element deployed on the ground, and the application function entity is deployed on the ground; wherein the onboard base station or the first core network element deployed on the satellite establishes a communication link with the second core network element deployed on the ground through a gateway; The obtaining of the availability information of the service link between the satellite base station and the user equipment includes: when the communication link between the gateway and the second core network element is available, receiving the availability information of the service link sent by the satellite base station or the first core network element deployed on the satellite through the communication link.

9. The satellite-based communication method of claim 8, further comprising: caching a request message sent by the application function entity for requesting to obtain the availability information of the service link, and setting a second timer for the request message; Before the timing of the second timer exceeds a second set duration, if the availability information of the service link sent by the onboard base station or the first core network element deployed on the satellite is received through the communication link, the availability information of the service link is sent to the application function entity; If the availability information of the service link is not obtained before the second timer exceeds the second set duration, it is determined that the feedback of the availability information of the service link has timed out.

10. The satellite-based communication method according to claim 9, wherein: The second set duration is greater than or equal to a predicted communication interruption time of a communication link between the onboard base station or the core network element deployed on the satellite and the gateway; or The second set duration is greater than or equal to the sum of the predicted communication interruption time and the communication propagation delay of the communication link; The predicted communication interruption time of the communication link is determined based on the ephemeris information of the satellite.

11. The satellite-based communication method according to any one of claims 1 to 10, wherein: The availability information of the service link includes at least one of the following: real-time availability information and availability information within a future set time period.

12. The satellite-based communication method according to any one of claims 1 to 10, wherein: Determine the availability information of the service link according to at least one of the following information: ephemeris information of the satellite-borne base station, subscription information of the user equipment, and interaction information between the user equipment and the satellite-borne base station.

13. A satellite-based communication method, performed by an application function entity, wherein the satellite has at least an onboard base station deployed thereon, the communication method comprising: receiving availability information of a service link sent by a core network element, where the service link is a communication link established between the satellite-borne base station and user equipment; Data is sent to the user equipment through the service link according to the availability information of the service link.

14. The satellite-based communication method according to claim 13, wherein: The sending data to the user equipment through the service link according to the availability information of the service link includes: If it is determined according to the availability information of the service link that the service link is available, sending data to the user equipment through the service link; or If it is determined according to the availability information of the service link that the communication quality of the service link meets a predetermined condition, data is sent to the user equipment through the service link.

15. The satellite-based communication method according to claim 13 or 14, wherein: Before receiving the service link availability information sent by the core network element, the communication method further includes: generating a request message, wherein the request message is used to request availability information of the service link; Send the request message to the core network element.

16. A satellite-based communication device deployed in a core network element, wherein: At least a satellite-borne base station is deployed on the satellite, and the communication device includes: an acquiring unit, configured to acquire availability information of a service link between the satellite-borne base station and the user equipment; The sending unit is configured to open the availability information of the service link to the application function entity, wherein the availability information of the service link serves as a basis for the application function entity to send data to the user equipment through the satellite base station.

17. A satellite-based communication device, deployed on an application function entity, wherein at least a satellite-borne base station is deployed on the satellite, the communication device comprising: a receiving unit configured to receive availability information of a service link sent by a core network element, where the service link is a communication link established between the satellite base station and the user equipment; The processing unit is configured to send data to the user equipment through the service link according to the availability information of the service link.

18. A computer-readable medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the satellite-based communication method according to any one of claims 1 to 15 is implemented.

19. An electronic device comprising: one or more processors; A memory for storing one or more computer programs, which, when executed by the one or more processors, enables the electronic device to implement the satellite-based communication method according to any one of claims 1 to 15.

20. A computer program product, comprising a computer program, wherein the computer program is stored in a computer-readable storage medium, and a processor of an electronic device reads and executes the computer program from the computer-readable storage medium, so that the electronic device performs the satellite-based communication method according to any one of claims 1 to 15.

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