CN116743240B

CN116743240B - Satellite switching method and device, electronic equipment and storage medium

Info

Publication number: CN116743240B
Application number: CN202311028273.2A
Authority: CN
Inventors: 汪春霆; 吴迪; 严玉平
Original assignee: China Star Network System Research Institute Co ltd
Current assignee: China Star Network System Research Institute Co ltd
Priority date: 2023-08-15
Filing date: 2023-08-15
Publication date: 2023-11-14
Anticipated expiration: 2043-08-15
Also published as: CN116743240A

Abstract

The embodiment of the application provides a satellite switching method, a device, electronic equipment and a storage medium, and relates to the technical field of satellite mobile communication, wherein the method comprises the following steps: determining a first service satellite to be switched and switching time corresponding to the first user equipment according to a measurement report of the first user equipment, ephemeris information of the satellite and position information of the first user equipment, wherein the current service satellite corresponding to the first user equipment is a second service satellite; when the switching time is reached, the service satellite of the first user equipment is switched from the second service satellite to the first service satellite, so that the first user equipment performs service communication with the second user equipment through the first service satellite and a third service satellite, and the third service satellite is the current service satellite corresponding to the second user equipment. By applying the technical scheme provided by the embodiment of the application, the problem of poor service continuity between user equipment in the TtoT mode can be solved.

Description

Satellite switching method and device, electronic equipment and storage medium

Technical Field

The present application relates to the field of satellite mobile communications technologies, and in particular, to a satellite switching method, a satellite switching device, an electronic device, and a storage medium.

Background

Compared with a ground network, the satellite communication system has larger transmission delay, so for voice isochronous sensitive data service, the satellite communication system can adopt a single-hop mode of end-to-end (Terminal to Terminal, ttoT) for processing so as to reduce the transmission delay and improve the user experience.

For low orbit satellite communication systems, the satellite movement speed relative to the ground is very fast, which results in more frequent intra-or inter-satellite beam switching of the ue, and thus poor service continuity between ues in TtoT mode.

Disclosure of Invention

An embodiment of the application aims to provide a satellite switching method, a satellite switching device, electronic equipment and a storage medium, which are used for solving the problem of poor service continuity between user equipment in a Tto mode. The specific technical scheme is as follows:

in a first aspect, an embodiment of the present application provides a satellite switching method, where the method includes:

determining a first service satellite to be switched and switching time corresponding to first user equipment according to a measurement report of the first user equipment, ephemeris information of the satellite and position information of the first user equipment, wherein a current service satellite corresponding to the first user equipment is a second service satellite;

And when the switching time is reached, switching the service satellite of the first user equipment from the second service satellite to the first service satellite so that the first user equipment performs service communication with the second user equipment through the first service satellite and a third service satellite, wherein the third service satellite is a current service satellite corresponding to the second user equipment.

In some embodiments, the method further comprises:

determining a target beam on a first service satellite according to a measurement report of the first user equipment, ephemeris information of the satellite and position information of the first user equipment; the target beam is a beam that is accessed when the first serving satellite is switched to the serving satellite of the first user equipment.

In some embodiments, the step of switching the service satellite of the first user equipment from the second service satellite to the first service satellite comprises:

transmitting first context information of the first user equipment to the first service satellite and the third service satellite, wherein the first context information indicates that the first service satellite is a service satellite of the first user equipment;

The first service satellite configures a data path between the first service satellite and the third service satellite according to the first context information;

the third service satellite modifies a data path between the second service satellite and the third service satellite to a data path between the first service satellite and the third service satellite according to the first context information.

In some embodiments, when a portion of the base station functionality is deployed on the satellite, the terrestrial network transmits a first request to the first serving satellite, the first request carrying the first context information.

In some embodiments, the first request is a terminal context setup request.

In some embodiments, the second service satellite sends a second request to the first service satellite over the terrestrial network, the second request carrying the first context information, when all base station functionality is deployed on the satellite.

In some embodiments, the second request is a handover request.

In some embodiments, when all base station functionality is deployed on a satellite,

the second service satellite sends a third request to the first service satellite through a neighboring satellite interface between the second service satellite and the first service satellite, wherein the third request carries the first context information.

In some embodiments, the third request is a handover request.

In some embodiments, when some or all of the base station functionality is deployed on the satellite,

the ground network sends a fourth request to the third service satellite, the fourth request carrying the first context information.

In some embodiments, the fourth request is a terminal context modification request.

In some embodiments, the method further comprises:

transmitting a first message to the first user equipment, wherein the first message indicates the first user equipment to switch from the second service satellite to the first service satellite;

after the satellite switching is completed, the second service satellite is instructed to release second context information of the first user equipment, and the second context information is instructed to serve as the service satellite of the first user equipment.

In some embodiments, when part of the base station functionality is deployed on the satellite,

the ground network sends a first message to the first user equipment through the second service satellite;

and after the satellite switching is completed, the first user equipment sends a second message to the ground network through the first service satellite.

after receiving a first command sent by a ground network, the second service satellite sends a first message to the first user equipment;

after the satellite switching is completed, the first user equipment sends a second message to the first service satellite;

and the first service satellite sends a third message to the ground network after receiving the second message.

In some embodiments, the first command is a handover command and the third message is a handover notification message.

In some embodiments, the first message is an RRC connection reconfiguration message and the second message is an RRC connection reconfiguration complete message.

the ground network sends a fourth message to the second service satellite, the fourth message instructing the second service satellite to release the second context information.

In some embodiments, the fourth message is a terminal context release message.

In some embodiments, when a portion of the base station functionality is deployed on a satellite, distributed Units (DUs) are deployed at the satellite and Centralized Units (CUs) are deployed at the ground network; or the physical layer is deployed on the satellite, and the part above the MAC layer is deployed on the ground network;

When all base station functions are deployed on the satellite, DUs and CUs are deployed on the satellite.

In some embodiments, the first context information includes an address of the first user device, an address of the first service satellite, an address of the third service satellite, an address of the second user device, and a data path parameter for configuring a data path between the first service satellite and the third service satellite.

In some embodiments, when a part of base station functions are deployed on a satellite, a ground network determines a first service satellite to be switched and a switching time corresponding to a first user equipment according to a measurement report of the first user equipment, ephemeris information of the satellite and position information of the first user equipment;

when all base station functions are deployed on the satellites, the second service satellite determines a first service satellite to be switched and switching time corresponding to the first user equipment according to a measurement report of the first user equipment, ephemeris information of the satellites and position information of the first user equipment.

In some embodiments, the second service satellite and the third service satellite are the same satellite or different satellites.

In some embodiments, the first service satellite and the third service satellite are the same satellite or different satellites.

In a second aspect, an embodiment of the present application provides a satellite switching device, including:

and a determination module: the method comprises the steps of determining a first service satellite to be switched and switching time corresponding to first user equipment according to a measurement report of the first user equipment, ephemeris information of the satellite and position information of the first user equipment, wherein a current service satellite corresponding to the first user equipment is a second service satellite;

and a switching module: and when the switching time is reached, switching the service satellite of the first user equipment from the second service satellite to the first service satellite, so that the first user equipment performs service communication with the second user equipment through the first service satellite and a third service satellite, wherein the third service satellite is a current service satellite corresponding to the second user equipment.

In a third aspect, an embodiment of the present application provides an electronic device, including a processor, a communication interface, a memory, and a communication bus, where the processor, the communication interface, and the memory complete communication with each other through the communication bus;

A memory for storing a computer program;

and the processor is used for realizing any one of the methods when executing the program stored in the memory.

In a fourth aspect, embodiments of the present application provide a computer readable storage medium having a computer program stored therein, which when executed by a processor, implements any of the methods described above.

Embodiments of the present application also provide a computer program product comprising instructions which, when run on a computer, cause the computer to perform any of the methods described above.

The embodiment of the application has the beneficial effects that:

in the technical scheme provided by the embodiment of the application, judgment is carried out based on the measurement report of the first user equipment, the ephemeris information of the satellite and the position information of the first user equipment, and the first service satellite and the switching time which need to be switched are determined; when the handoff time is reached, the first service satellite is able to provide a better quality of service for the first user device than the second service satellite. Therefore, when the switching time is reached, the first user equipment switches the second service satellite which provides service for the first user equipment to the first service satellite, so that the switching of the service satellites is completed, the service continuity between the first user equipment in the TtoT mode can be realized, and the problem of poor service continuity between the user equipment in the TtoT mode is solved.

Of course, it is not necessary for any one product or method of practicing the application to achieve all of the advantages set forth above at the same time.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the application, and other embodiments may be obtained according to these drawings to those skilled in the art.

Fig. 1 is a schematic flow chart of a satellite switching method according to an embodiment of the present application;

fig. 2 is a first signaling schematic diagram of a satellite switching method according to an embodiment of the present application;

fig. 3 is a second signaling schematic diagram of a satellite switching method according to an embodiment of the present application;

fig. 4 is a third signaling schematic diagram of a satellite switching method according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a satellite switching device according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by the person skilled in the art based on the present application are included in the scope of protection of the present application.

Compared with a ground network, the satellite communication system has larger transmission delay, and for data services sensitive to delay such as voice, the satellite communication system can adopt a terminal-satellite-terminal mode for processing, namely adopts a Tto mode for processing, so that the transmission delay is reduced, and the user experience is improved.

For a high-orbit satellite communication system, one high-orbit satellite can meet most of service requirements in a TtoT mode because the satellite is static relative to the ground; for low-orbit satellite communication systems, the satellite movement speed relative to the ground is very high, which results in more frequent intra-satellite or inter-satellite beam switching of the ue, and thus poor service continuity between ues in TtoT mode.

In order to solve the above-mentioned problems, the embodiment of the present application provides a satellite switching method, which is applied to a device having a control function of a base station, such as a control device for deploying the gNB-CU function in a ground network, or a satellite deploying all the functions of the gNB, etc. The specific execution subject can be determined according to the satellite-ground division scene. In the embodiment of the application, the satellite-ground division scene can be divided into the following two types.

In a first scenario, a portion of the base station functionality is deployed on a satellite.

In scenario one, the base station function deployed on the satellite may be a Distributed Unit (DU), that is, the satellite-to-ground division is: distributed units are deployed at satellites, and Centralized Units (CUs) are on the ground network; the base station functions deployed on the satellite may be physical layer, that is, satellite-to-ground division: the physical layer is disposed in the satellite, the MAC layer and above in the terrestrial network. In the embodiment of the application, in the first scene, the satellite-ground division can be set in a self-defining way according to the requirement. For example, the physical layer and the MAC layer are at the satellite, and the rest are deployed on the terrestrial network.

In the scene, the device with the control function of the base station is located in the ground network, and at this time, the execution main body of the satellite switching method is the ground network, for example, the control device with the gNB-CU function is deployed in the ground network.

And the second scenario is that all base station functions are deployed on the satellite.

In the embodiment of the application, other functions, such as a user plane function (User Plane Function, UPF) and the like, can be deployed on the satellite, which is not limited.

In the second scenario, the device having the control function of the base station is located in a satellite, and in this case, the main body of execution of the satellite switching method is the satellite.

In addition, a Core Network (CN) is deployed in the ground Network. The mechanism of the CN is determined based on the mechanism of the base station. For example, the base station is a 4G base station (eNB), and the CN is a 4G core network (4G Core Network,4GC); the base station is a 5G base station (gNB), and the CN is a 5G core network (5G Core Network,5GC), accordingly. The CN may be used to process user data, support transmission and reception of signaling, and the control functions implemented by the above-mentioned control device may be understood as being implemented by the CN.

In the satellite switching method, a first service satellite and switching time which need to be switched are determined based on a measurement report of first user equipment, ephemeris information of the satellite and position information of the first user equipment; when the handoff time is reached, the first service satellite is able to provide a better quality of service for the first user device than the second service satellite. Therefore, when the switching time is reached, the first user equipment switches the second service satellite which provides service for the first user equipment to the first service satellite, so that the switching of the service satellites is completed, the service continuity between the first user equipment in the TtoT mode can be realized, and the problem of poor service continuity between the user equipment in the TtoT mode is solved.

The satellite switching method provided by the embodiment of the application is described in detail below through a specific embodiment. For convenience of explanation, the following description will be given with the base station as the execution subject, and the present application is not limited thereto.

Referring to fig. 1, fig. 1 is a schematic flow chart of a satellite switching method according to an embodiment of the present application, where the method includes the following steps:

step S11: and determining a first service satellite to be switched and switching time corresponding to the first user equipment according to the measurement report of the first user equipment, the ephemeris information of the satellite and the position information of the first user equipment, wherein the current service satellite corresponding to the first user equipment is a second service satellite.

In the embodiment of the application, the service satellite is a satellite for providing service for the user equipment. The first user equipment may be any user equipment that needs to switch service satellites, where the first service satellite is a satellite that provides service to the first user equipment after switching, and the second service satellite is a satellite that currently provides service to the first user equipment, that is, a satellite that provides service to the first user equipment before switching.

The first user equipment measures the communication quality between the first user equipment and each service satellite to obtain a measurement report, wherein each service satellite comprises a second service satellite, a neighboring satellite (such as the first service satellite) of the second service satellite, and the like. The first user equipment reports the measurement report to the base station. In addition, the base station may obtain ephemeris information of each satellite and location information of the first user equipment.

The measurement report can be reported to the base station by the first user equipment periodically, or can be actively acquired from the first user equipment by the base station; the location information of the first user equipment may be uploaded to the base station by the first user equipment, or may be determined by the base station according to a cellular network positioning mode or the like; the ephemeris information of the satellite can be sent to the base station by a satellite communication system, or can be obtained by the base station through the modes of internet downloading or an ephemeris prediction algorithm and the like.

The base station may perform a decision based on the measurement report, satellite ephemeris information, and location information of the first user equipment in combination with a set decision condition, determine a satellite capable of providing better service for the first user equipment, i.e. the first service satellite, and determine a time for switching to the first service satellite, i.e. a switching time. The decision condition can be set according to actual requirements. For example, the decision condition may be: a satellite having a communication quality with the first user device higher than a preset quality threshold and capable of providing service to the first user device with a communication quality higher than the preset quality threshold for a longest period of time; the decision condition may also be: satellites with the highest communication quality with the first user device, etc.

In some embodiments, the second and third service satellites may be the same satellite or may be different satellites; the first service satellite and the third service satellite may be the same satellite or different satellites.

In the embodiment of the application, when the first user equipment and the second user equipment are served by the same satellite, the second service satellite and the third service satellite are the same satellite; the second service satellite and the third service satellite are different satellites when the first user device and the second user device are serviced by different satellites.

After the base station makes the decision, if the determined satellite capable of providing the better service for the first user equipment is the third service satellite, the third service satellite is the first service satellite, that is, the first service satellite and the third service satellite are the same satellite. After the base station determines, if the determined satellite capable of providing the better service for the first user equipment is other satellites than the third service satellite, the first service satellite and the third service satellite are different satellites.

The second user equipment is user equipment which performs service communication with the first user equipment. The third service satellite is the satellite currently providing service to the second user device.

Step S12: when the switching time is reached, the service satellite of the first user equipment is switched from the second service satellite to the first service satellite, so that the first user equipment performs service communication with the second user equipment through the first service satellite and a third service satellite, and the third service satellite is the current service satellite corresponding to the second user equipment.

In the embodiment of the present application, when the switching time is reached, the base station switches the service satellite of the first user equipment to the first service satellite, for example, establishes a data path between the first service satellite and the third service satellite, and the first user equipment is connected with the first service satellite. After switching the service satellite, the first user equipment and the second user equipment complete service communication in the TfoT mode through the first service satellite and the third service satellite.

In some embodiments, the base station may further determine a target beam on the first service satellite according to the measurement report of the first user equipment, the ephemeris information of the satellite, and the location information of the first user equipment; the target beam is a beam that is accessed when the first serving satellite is switched to the serving satellite of the first user equipment. That is, when the handoff time is reached, the base station hands off the service satellite of the first user device from the second service satellite to the first service satellite and accesses the target beam on the first service satellite.

A satellite has one or more beams, different beams, and different directions. And determining the target wave beam, so that the satellite switching can be controlled more finely, and the service quality is ensured.

In some embodiments, the base station may obtain first context information indicating that the first service satellite is a service satellite of the first user equipment. The base station transmits first context information of the first user equipment to the first service satellite and the third service satellite. The first service satellite may configure a data path between the first service satellite and the third service satellite based on the first context information. The third service satellite may modify a data path between the second service satellite and the third service satellite to a data path between the first service satellite and the third service satellite based on the first context information. Based on this, the establishment of the data path between the first service satellite and the third service satellite is completed.

In the embodiment of the present application, the first context information may include an address of the first user equipment, an address of the first service satellite, an address of the third service satellite, an address of the second user equipment, and data path parameters of the address of the first service satellite and the address of the third service satellite.

The address of the user equipment can be gNB-DU UE F1AP ID, temporary mobile user identity (Temporary Mobile Subscriber Identity, S-TMSI), or satellite internal user equipment identity which can uniquely identify the user equipment in a satellite, etc.; the satellite address may be a satellite identification (Identity, ID), a 5G base station identification (the next Generation Node B ID, gNB ID), a 5G base station distribution unit identification (gNodeB Distributed Unit Identity, gNB-DU ID), or a satellite internet protocol (Internet Protocol, IP) address, etc.; the data path parameters may be general packet radio transport protocol tunnel (GPRS Tunneling Protocol, GTP) addresses or custom tunnel parameters that may be used to configure the data path between the first service satellite and the third service satellite. The inter-satellite TtoT interface used in the data path between the first service satellite and the third service satellite may be an Xn/X2 user plane interface, an inter-DU interface, or a custom interface between satellites, which is not limited.

In the embodiment of the application, the base station can send the first context information of the first user equipment to the first service satellite and the third service satellite, and after the first service satellite receives the first context information, the data path between the first service satellite and the third service satellite can be configured based on the data path parameters in the first context information. After the third service satellite receives the first context information, the data path between the second service satellite and the third service satellite can be modified to be the data path between the first service satellite and the third service satellite based on the data path parameter in the first context information and the address of the first service satellite.

In the embodiment of the application, the first service satellite and the third service satellite can establish the data path between the first service satellite and the third service satellite based on the first context information, so that the data transmission between the first service satellite and the third service satellite can be conveniently carried out after the service satellite is switched from the second service satellite to the first service satellite by the subsequent first user equipment.

In some embodiments, after configuring the data path between the first service satellite and the third service satellite, the base station may send a first message to the first user equipment, instructing the first user equipment to switch from the second service satellite to the first service satellite; after the satellite switching is completed, the base station may instruct the second service satellite to release the second context information of the first user equipment, where the second context information indicates that the second service satellite is a service satellite of the first user equipment.

In the embodiment of the application, the base station can send the first message to the first user equipment, the first user equipment can switch the second service satellite to the first service satellite after receiving the first message, and after the satellite switching is completed, the first user equipment can send the second message to the base station through the first service satellite to inform the base station that the service satellite of the first user equipment has been switched to the first service satellite, and at the moment, the base station can instruct the second service satellite to release the second context information of the first user equipment.

In some embodiments, the first message may be an RRC connection reconfiguration message and the second message may be an RRC connection reconfiguration complete message.

The base station may send an RRC connection reconfiguration message to the first user equipment, after the first user equipment receives the RRC connection reconfiguration message, may switch the second service satellite to the first service satellite, for example, establish RRC connection between the first user equipment and the first service satellite, after RRC connection reconfiguration is completed, that is, after satellite switching is completed, the first user equipment may send an RRC connection reconfiguration complete message to the base station through the first service satellite, to inform the base station that the service satellite of the first user equipment has been switched to the first service satellite, and at this time, the base station may instruct the second service satellite to release the second context information of the first user equipment.

The second context information may include an address of the first user device, an address of the second service satellite, an address of the third service satellite, an address of the second user device, and data path parameters of the address of the second service satellite and the address of the third service satellite, corresponding to the first context information.

In some embodiments, after completing the data path establishment between the first service satellite and the third service satellite and the first user equipment completes the satellite handoff, the base station may send a fourth message to the second service satellite instructing the second service satellite to release the second context information. And the second service satellite releases the second context information after receiving the fourth message, and sends a fifth message to the base station after the release of the second context information is completed, so as to inform the base station that the release of the second context information is completed. Thus, the service satellite of the first user equipment is switched from the second service satellite to the first service satellite, and the first user equipment can perform service communication with the second user equipment through the first service satellite and the third service satellite.

In some embodiments, the fourth message may be a terminal context release message and the fifth message may be a terminal context release complete message.

The base station may send a terminal context release message to the second service satellite instructing the second service satellite to release the second context information. And the second service satellite releases the second context information after receiving the terminal context release message, and sends a terminal context release completion message to the base station after the release of the second context information is completed, so as to inform the base station that the release of the second context information is completed.

The satellite switching method can be applied to the two satellite-ground division scenes, wherein the first scene is that part of base station functions are deployed on a satellite, and the second scene is that all base station functions are deployed on the satellite.

For the above two satellite-to-ground division scenarios, the signaling flow of the satellite switching method provided in the embodiment of the present application is different, and the detailed description is given below with reference to the signaling diagrams of satellite switching shown in fig. 2-4. In fig. 2-4, the terrestrial network sending a request or message to a user device or satellite may be understood as the CN of the terrestrial network sending a request or message to a user device or satellite.

Scene one: part of the base station functionality is deployed on the satellite. At this time, the control function of the base station is located in the ground network. The ground network can determine a first service satellite to be switched and switching time corresponding to the first user equipment according to the measurement report of the first user equipment, the ephemeris information of the satellite and the position information of the first user equipment; when the handoff time is reached, the ground network may send a first request, such as a terminal context setup request (UE Context Setup Request), carrying first context information to the first service satellite, instructing the first service satellite to establish a data path between the first service satellite and the third service satellite. After the first service satellite receives the terminal context establishment request and establishes the data paths of the first service satellite and the third service satellite, a first response, such as a terminal context establishment response (UE Context Setup Response), may be sent to the ground network to inform the ground network that the first service satellite has established the data paths of the first service satellite and the third service satellite.

In addition, the ground network may send a fourth request, such as a terminal context modification request (UE Context Modification Request), carrying the first context information to the third service satellite, instructing the third service satellite to modify the data paths of the second and third service satellites to the data paths of the first and third service satellites. After the third service satellite completes the data path modification, a second response, such as a terminal context modification response (UE Context Modification Response), may be sent to the ground network informing the ground network that the third service satellite has established the data path between the first service satellite and the third service satellite. Thereby, the data path establishment between the first service satellite and the third service satellite is completed.

The ground network may also send a first message, such as an RRC connection reconfiguration message (RRC Connection Reconfiguration), to the first user equipment via the second service satellite instructing the first user equipment to switch the service satellite from the second service satellite to the first service satellite; after the RRC connection reconfiguration is completed, the first user equipment may send a second message, such as an RRC connection reconfiguration complete message (RRC Connection Reconfiguration Complete), to the terrestrial network through the first service satellite, informing the terrestrial network that the RRC connection reconfiguration is completed. Thereby, the service satellite of the first user equipment is switched to the first service satellite.

The ground network may also send a fourth message, such as a terminal context release message (UE Context Release Command), to the second service satellite instructing the second service satellite to release the second context information; after the second service satellite releases the second context information, a fifth message, such as a terminal context release complete message (UE Context Release Complete), may be sent to the ground network informing the ground network that the second service satellite has released the second context information.

For example, in a 5G non-terrestrial network (non-terrestrial network, NTN) architecture, the functionality of 5G distributed units (gNB-DUs) is deployed on satellites, in terrestrial networks being 5G centralized units (gNB-CUs) and 5GC. Referring to fig. 2, taking a User Equipment a (UEa) as a first User Equipment, a User Equipment B (User Equipment B, UEb) as a second User Equipment, a satellite a as a second service satellite (i.e. a source service satellite of the UEa), a satellite B as a third service satellite (a service satellite of the UEb), a satellite C as a first service satellite (a target service satellite of the UEa) as an example, the UEa and the UEb perform TtoT service, and a User plane data path is: user equipment a-satellite B-user equipment B. The signaling flow for satellite handoff is as follows.

Step S21: the user equipment a sends a measurement report to the ground network.

Step S22: the terrestrial network decides the handoff time and satellite C based on the measurement report, the location information of the user equipment a, and the satellite ephemeris information.

Step S23: the terrestrial network sends a terminal context setup request to satellite C.

In the embodiment of the application, the terminal context establishment request carries first context information of the UEa, wherein the first context information comprises an address of the user equipment a, an address of the user equipment B, an address of the satellite C, an address of the satellite B and data path parameters; the data path parameters may configure the path parameters of satellite B and satellite C. The first context information is TtoT context information, and the satellite C needs to maintain TtoT context information of the UEa, and configures a data path between the satellite C and the satellite B of the current service.

Step S24: satellite C sends a terminal context setup response to the terrestrial network.

Step S25: the terrestrial network sends a terminal context modification request to satellite B.

In the embodiment of the present application, the terminal context modification request carries the first context information of the UEa, and the satellite B may modify the data path between the satellite a and the satellite B of the current service into the data path between the satellite C and the satellite B based on the first context information.

Step S26: satellite B sends a terminal context modification response to the terrestrial network.

Step S27: the terrestrial network transmits an RRC connection reconfiguration message to the user equipment a through satellite a.

Step S28: the user equipment a transmits an RRC connection reconfiguration complete message to the terrestrial network through the satellite C.

The RRC connection reconfiguration procedure is completed through steps S27-S28, and UEa is handed over from satellite a to satellite C.

Step S29: the terrestrial network sends a terminal context release message to satellite a.

Step S210: satellite a sends a terminal context release complete message to the terrestrial network.

After the ue a is successfully switched, the ground network initiates a terminal context release process to the satellite a, and releases the TtoT context information of the ue a, including the TtoT context information of the ue a, so as to save the resources of the satellite a.

Scene II: all base station functions are deployed on the satellite.

The second service satellite may determine a first service satellite to be switched and a switching time corresponding to the first user equipment according to the measurement report of the first user equipment, ephemeris information of the satellite, and position information of the first user equipment. When the handoff time is reached, the second service satellite may send a second request carrying the first context information to the first service satellite over the terrestrial network.

For example, the second service satellite may send a handoff requirement (e.g., handover Required) to the terrestrial network, instructing the terrestrial network to send a second Request, such as a handoff Request (handoff Request), to the first service satellite, the handoff Request carrying the first context information. After the first service satellite receives the handoff request and establishes the data paths of the first service satellite and the third service satellite, a sixth message, such as a handoff request acknowledgement message (e.g., handover Request Acknowledge), may be sent to the ground network informing the ground network that the first service satellite has established the data paths of the first service satellite and the third service satellite.

In some embodiments, the second service satellite may further send a third Request, such as a Handover Request (Handover Request), to the first service satellite through a neighboring satellite interface between the second service satellite and the first service satellite, where the Handover Request carries the first context information. The adjacent star interfaces may also be referred to as inter-star interfaces, and may be Xn/X2 user plane interfaces, interfaces between Distributed Units (DUs), and custom interfaces between satellites.

The ground network may also send a first command, such as a handoff command (Handover Commmand), to the second service satellite. After receiving the switching command sent by the ground network, the second service satellite may send a first message, such as an RRC connection reconfiguration message (RRC Connection Reconfiguration), to the first user equipment, instructing the first user equipment to switch the service satellite from the second service satellite to the first service satellite; after the RRC connection reconfiguration is complete, the first user equipment may send a second message, such as an RRC connection reconfiguration complete message, to the first service satellite (RRC Connection Reconfiguration Complete); after receiving the second message, the first service satellite may send a third message, such as a Handover Notify message, to the terrestrial network, informing the terrestrial network that RRC connection reconfiguration is complete. Thereby, the service satellite of the first user equipment is switched to the first service satellite.

For example, in a 5G NTN architecture, the functions of both gNB-DU and gNB-CU are deployed on the satellite, 5GC in the terrestrial network. Referring to fig. 3, taking ue a as a first ue, ue B as a second ue, satellite a as a second service satellite (i.e. the source service satellite of UEa), satellite B as a third service satellite (the service satellite of UEb), and satellite C as a first service satellite (the target service satellite of UEa), the UEa and UEb perform TtoT service, and the user plane data path is: user equipment a-satellite B-user equipment B.

When the second service satellite transmits a second request, i.e., a handoff request, to the first service satellite through the terrestrial network, the signaling flow for satellite handoff is shown in fig. 3.

Step S31: the user equipment a sends a measurement report to satellite a.

Step S32: satellite a decides the handoff time and satellite C based on the measurement report, the location information of user equipment a, and satellite ephemeris information.

Step S33: satellite a sends a handoff request to the terrestrial network.

In the embodiment of the present application, the handover request may carry the first context information of the UEa, and inform the ground network that the service satellite of the ue a needs to be handed over to the satellite C, that is, the handover request is used for requesting the UEa to be handed over from the satellite a to the satellite C. The first context information may include an address of the user equipment a, an address of the user equipment B, an address of the satellite C, an address of the satellite B, and a data path parameter; the data path parameters may configure the data path between satellite B and satellite C.

Step S34: the terrestrial network sends a handoff request to satellite C.

Satellite C allocates air interface resources for UEa based on the handover request. The switching request carries first context information of the UEa, and the satellite C establishes a data path between the satellite C and the satellite B of the current service based on the first context information.

Step S35: satellite C sends a handoff request acknowledge message to the terrestrial network.

Step S36: the terrestrial network sends a terminal context modification request to satellite B.

Step S37: satellite B sends a terminal context modification response to the terrestrial network.

Step S38: the terrestrial network sends a handoff command to satellite a.

Step S39: satellite a sends an RRC connection reconfiguration message to user equipment a.

Step S310: the user equipment a transmits an RRC connection reconfiguration complete message to the satellite C.

Step S311: satellite C sends a handoff notification message to the terrestrial network.

The RRC connection reconfiguration procedure is completed through steps S38-S311, and UEa is handed over from satellite a to satellite C.

Step S312: the terrestrial network sends a terminal context release message to satellite a.

Step S313: satellite a sends a terminal context release complete message to the terrestrial network.

When the second service satellite sends a third request, i.e. a handoff request, to the first service satellite through the adjacent satellite interface between the second service satellite and the first service satellite, the signaling flow of satellite handoff is shown in fig. 4.

Step S41: the user equipment a sends a measurement report to satellite a.

Step S42: satellite a decides the handoff time and satellite C based on the measurement report, the location information of user equipment a, and satellite ephemeris information.

Step S41 to step S42 are the same as step S31 to step S32 described above.

Step S43: satellite a sends a handoff request to satellite C via the neighbor interface.

In the embodiment of the present application, the handover request may carry the first context information of the UEa. The first context information may include an address of the user equipment a, an address of the user equipment B, an address of the satellite C, an address of the satellite B, and a data path parameter; the data path parameters may configure the data path between satellite B and satellite C.

The subsequent steps S44 to S412 are the same as the steps S35 to S313 described above, and will not be repeated here.

Corresponding to the satellite switching method, the embodiment of the application also provides a satellite switching device, as shown in fig. 5, which comprises:

the determination module 51: the method comprises the steps of determining a first service satellite to be switched and switching time corresponding to first user equipment according to a measurement report of the first user equipment, ephemeris information of the satellite and position information of the first user equipment, wherein the current service satellite corresponding to the first user equipment is a second service satellite;

switching module 52: and when the switching time is reached, switching the service satellite of the first user equipment from the second service satellite to the first service satellite so that the first user equipment performs service communication with the second user equipment through the first service satellite and a third service satellite, wherein the third service satellite is the current service satellite corresponding to the second user equipment.

In some embodiments, the determination module 51: the method is also used for determining a target beam on the first service satellite according to the measurement report of the first user equipment, the ephemeris information of the satellite and the position information of the first user equipment; the target beam is a beam that is accessed when the first serving satellite is switched to the serving satellite of the first user equipment.

In some embodiments, the switching module 52 may be specifically configured to:

transmitting first context information of the first user equipment to a first service satellite and a third service satellite, wherein the first context information indicates that the first service satellite is a service satellite of the first user equipment;

the third service satellite modifies a data path between the second service satellite and the third service satellite to a data path between the first service satellite and the third service satellite based on the first context information.

In some embodiments, when a portion of the base station functionality is deployed on the satellite, the terrestrial network transmits a first request to a first serving satellite, the first request carrying first context information;

In some embodiments, the first request is a terminal context setup request.

In some embodiments, when all base station functionality is deployed on the satellite, the second service satellite sends a second request to the first service satellite over the terrestrial network, the second request carrying the first context information.

In some embodiments, the second request is a handover request.

In some embodiments, the third request is a handover request.

In some embodiments, the switching module 52 may also be configured to:

After the satellite switching is completed, the second service satellite is instructed to release the second context information of the first user equipment, and the second context information instructs the second service satellite to serve as the service satellite of the first user equipment.

the ground network sends a first message to the first user equipment through a second service satellite;

after the satellite switching is completed, the first user equipment sends a second message to the ground network through the first service satellite.

after receiving a first command sent by a ground network, a second service satellite sends a first message to first user equipment;

the first service satellite sends a third message to the ground network after receiving the second message.

The ground network transmits a fourth message to the second service satellite, the fourth message instructing the second service satellite to release the second context information.

In some embodiments, the fourth message is a terminal context release message.

In some embodiments, when part of the base station functionality is deployed on the satellite, the DU is deployed on the satellite and the CU is deployed on the terrestrial network; or the physical layer is deployed on the satellite, and the part above the MAC layer is deployed on the ground network;

In some embodiments, when a part of the base station functions are deployed on the satellite, the ground network determines a first service satellite to be switched and a switching time corresponding to the first user equipment according to a measurement report of the first user equipment, ephemeris information of the satellite and position information of the first user equipment;

when all the base station functions are deployed on the satellite, the second service satellite determines a first service satellite to be switched and switching time corresponding to the first user equipment according to the measurement report of the first user equipment, the ephemeris information of the satellite and the position information of the first user equipment.

The embodiment of the application also provides an electronic device, such as a base station, as shown in fig. 6, which comprises a processor 61, a communication interface 62, a memory 63 and a communication bus 64, wherein the processor 61, the communication interface 62 and the memory 63 complete communication with each other through the communication bus 64;

a memory 63 for storing a computer program;

the processor 61 is configured to implement any of the above-described satellite switching methods when executing the program stored in the memory 63.

The communication bus mentioned above for the electronic devices may be a peripheral component interconnect standard (Peripheral Component Interconnect, PCI) bus or an extended industry standard architecture (Extended Industry Standard Architecture, EISA) bus, etc. The communication bus may be classified as an address bus, a data bus, a control bus, or the like. For ease of illustration, the figures are shown with only one bold line, but not with only one bus or one type of bus.

The communication interface is used for communication between the electronic device and other devices.

The Memory may include random access Memory (Random Access Memory, RAM) or may include Non-Volatile Memory (NVM), such as at least one disk Memory. Optionally, the memory may also be at least one memory device located remotely from the aforementioned processor.

The processor may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP), etc.; but also digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), field programmable gate arrays (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

In yet another embodiment of the present application, there is also provided a computer readable storage medium having stored therein a computer program which when executed by a processor implements the steps of any of the satellite handoff methods described above.

In yet another embodiment of the present application, there is also provided a computer program product containing instructions that, when run on a computer, cause the computer to perform any of the satellite handoff methods of the above embodiments.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, for example, by wired (e.g., coaxial cable, optical fiber, digital Subscriber Line (DSL)), or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid State Disk (SSD)), etc.

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

In this specification, each embodiment is described in a related manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for apparatus, electronic devices, storage media, and computer program product embodiments, the description is relatively simple, as it is substantially similar to method embodiments, with reference to the description of method embodiments in part.

The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims

1. A satellite handoff method, the method comprising:

determining a first service satellite to be switched and switching time corresponding to first user equipment according to a measurement report of the first user equipment, ephemeris information of satellites and position information of the first user equipment, wherein a current service satellite corresponding to the first user equipment is a second service satellite, and the measurement report comprises measurement results of communication quality between the first user equipment and each satellite;

when the switching time is reached, switching the service satellite of the first user equipment from the second service satellite to the first service satellite so that the first user equipment performs service communication with the second user equipment through the first service satellite and a third service satellite, wherein the third service satellite is a current service satellite corresponding to the second user equipment;

the step of switching the service satellite of the first user equipment from the second service satellite to the first service satellite includes:

And sending first context information of the first user equipment to the first service satellite and the third service satellite, wherein the first context information indicates that the first service satellite is the service satellite of the first user equipment.

2. The method according to claim 1, wherein the method further comprises:

3. The method of claim 1, wherein the step of determining the position of the substrate comprises,

4. A method according to claim 3, wherein the terrestrial network transmits a first request to the first serving satellite when part of the base station functionality is deployed on the satellite, the first request carrying the first context information.

5. The method of claim 4, wherein the first request is a terminal context setup request.

6. A method according to claim 3, wherein the second service satellite sends a second request to the first service satellite over a terrestrial network when all base station functions are deployed on the satellite, the second request carrying the first context information.

7. The method of claim 6, wherein the second request is a handover request.

8. The method of claim 3, wherein, when all base station functions are deployed on the satellite,

9. The method of claim 8, wherein the third request is a handover request.

10. The method of claim 3, wherein, when some or all of the base station functionality is deployed on the satellite,

11. The method of claim 10, wherein the fourth request is a terminal context modification request.

12. A method according to claim 3, characterized in that the method further comprises:

13. The method of claim 12, wherein, when a portion of the base station functionality is deployed on a satellite,

14. The method of claim 12, wherein, when all base station functions are deployed on a satellite,

15. The method of claim 14, wherein the first command is a handover command and the third message is a handover notification message.

16. The method according to any of claims 13-15, wherein the first message is an RRC connection reconfiguration message and the second message is an RRC connection reconfiguration complete message.

17. The method of claim 12, wherein when some or all of the base station functionality is deployed on a satellite,

18. The method of claim 17, wherein the fourth message is a terminal context release message.

19. The method according to any of claims 4-11, 13-15 and 17, characterized in that when part of the base station functions are deployed on the satellite, the distributed units DU are deployed on the satellite and the centralized units CU are deployed on the ground network; or the physical layer is deployed on the satellite, and the part above the MAC layer is deployed on the ground network;

20. The method according to any of claims 3-15 and 17, wherein the first context information comprises an address of the first user device, an address of the first service satellite, an address of the third service satellite, an address of the second user device, and a data path parameter for configuring a data path between the first service satellite and the third service satellite.

21. The method according to any one of claims 1-11, 13-15 and 17, wherein,

when a part of base station functions are deployed on a satellite, a ground network determines a first service satellite to be switched and switching time corresponding to first user equipment according to a measurement report of the first user equipment, ephemeris information of the satellite and position information of the first user equipment;

22. The method of any one of claims 1-15 and 17, wherein the second service satellite and the third service satellite are the same satellite or different satellites.

23. The method of any one of claims 1-15 and 17, wherein the first service satellite and the third service satellite are the same satellite or different satellites.

24. A satellite switching device, the device comprising:

and a determination module: the method comprises the steps of determining a first service satellite to be switched and switching time corresponding to first user equipment according to a measurement report of the first user equipment, ephemeris information of satellites and position information of the first user equipment, wherein a current service satellite corresponding to the first user equipment is a second service satellite, and the measurement report comprises measurement results of communication quality between the first user equipment and each satellite;

and a switching module: when the switching time is reached, switching the service satellite of the first user equipment from the second service satellite to the first service satellite, so that the first user equipment performs service communication with the second user equipment through the first service satellite and a third service satellite, wherein the third service satellite is a current service satellite corresponding to the second user equipment;

The switching module is specifically configured to:

25. The electronic equipment is characterized by comprising a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory are communicated with each other through the communication bus;

a memory for storing a computer program;

a processor for implementing the method of any one of claims 1-23 when executing a program stored on a memory.

26. A computer readable storage medium, characterized in that the computer readable storage medium has stored therein a computer program which, when executed by a processor, implements the method of any of claims 1-23.