CN111836357B

CN111836357B - Communication method and device

Info

Publication number: CN111836357B
Application number: CN201910310680.XA
Authority: CN
Inventors: 刘琼; 晋英豪; 谭巍
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-04-17
Filing date: 2019-04-17
Publication date: 2022-08-26
Anticipated expiration: 2039-04-17
Also published as: WO2020211727A1; CN111836357A

Abstract

The application provides a communication method and device, relates to the technical field of communication, and can solve the problem that a terminal in a non-terrestrial network frequently executes a TAU. The method comprises the following steps: and the terminal receives the broadcast message from the access network equipment and stores the information of the tracking area. Wherein the broadcast message includes information of a tracking area, and the information of the tracking area includes information of a service gateway. The method is applied to the position management process of the terminal.

Description

Communication method and device

Technical Field

The present application relates to the field of communications technologies, and in particular, to a communication method and apparatus.

Background

In a mobile network, a Tracking Area (TA) manner is adopted to track the location of a terminal, so as to facilitate location management and paging of the terminal. Specifically, the core network device configures a tracking area list (TA list) for the terminal. Generally, a TA list contains one or more Tracking Area Codes (TACs), and one TAC is used to identify one TA. One TA may contain one or more cells. Subsequently, if the terminal moves within the cell indicated by the configured TA list, the Tracking Area Update (TAU) does not need to be performed. Correspondingly, when the terminal has a service, the core network device pages the terminal in the area corresponding to the configured TA list. On the contrary, if the terminal moves out of the cell indicated by the TA list, the core network device does not acquire the latest position of the terminal, and the terminal needs to execute the TAU, so that the core network device acquires the current TA of the terminal, and the core network device can update the TA list of the terminal.

In order to compensate for the problem of coverage holes of ground base stations, non-terrestrial networks (NTN) are introduced, wherein the ground base stations or part of functions of the base stations are deployed on an idle platform or a satellite so as to provide seamless coverage for terminals.

If the TAU mechanism of the mobile network is directly applied to the non-terrestrial network, due to the idle platform or the high-speed movement of the satellite, even if the terminal does not move or moves at a low speed, the serving cell of the terminal changes, and the terminal is likely to frequently move out of the cell indicated by the TA list, so that the terminal frequently executes TAU, and the signaling overhead increases.

Disclosure of Invention

The embodiment of the application provides a communication method and a communication device, which are intended to avoid a terminal in a non-terrestrial network from frequently executing a TAU.

In order to achieve the above purpose, the embodiment of the present application adopts the following technical solutions:

in a first aspect, an embodiment of the present application provides a communication method, where the method is applied to a terminal or a chip of the terminal, and the method includes: the terminal receives the broadcast message from the access network device and stores the information of the tracking area. Wherein the broadcast message includes information of a tracking area, and the information of the tracking area includes information of a service gateway.

According to the communication method provided by the embodiment of the application, the terminal receives the information of the tracking area and stores the information of the tracking area. Wherein the information of the tracking area includes information of a serving gateway. Compared with the prior art, because a no-load platform or a satellite moves at a high speed, and a service cell of a terminal also changes, so that the terminal frequently executes TAU.

In one possible design, the terminal may further perform the following steps: if the tracking area information in the received broadcast message is not in the tracking area List TA List of the terminal, the terminal performs tracking area update TAU.

Thus, the terminal can determine whether to execute the TAU only by judging whether the currently received information of the serving gateway exists in the TA List. As can be understood from the above method, when the serving cell of the terminal or the access network device to which the terminal is accessed changes, the serving gateway to which the terminal belongs does not necessarily change, and therefore the tracking area information does not necessarily change. Thus, the tracking area information does not exceed the range indicated by the TA List, and the terminal does not perform TAU. Compared with the prior art that the serving cell changes to cause frequent execution of the TAU, the method and the device can greatly reduce the times of the terminal executing the TAU and avoid the terminal frequently executing the TAU.

In a possible design, after the terminal receives the broadcast message from the access network device, the terminal may further perform the following steps:

and if the information of the tracking area with the service gateway as the granularity is not in the TA List of the terminal, the terminal executes the TAU.

In one possible design, the information of the tracking area further includes information of a sub-area, and the sub-area belongs to a coverage area of the serving gateway; after the terminal receives the broadcast message from the access network device, the terminal may further perform the following steps:

and if the information of the tracking area with the sub-area as the granularity is not in the TA List of the terminal, the terminal executes the TAU.

In a second aspect, an embodiment of the present application provides a communication method, where the method is applied to an access network device or a chip of the access network device, and the method includes: and the access network equipment acquires the information of the tracking area and sends a broadcast message. Wherein the information of the tracking area includes information of a service gateway, and the broadcast message includes information of the tracking area.

In a possible design, the obtaining, by the access network device, information of the tracking area includes:

the access network equipment determines a service gateway; the service gateway is a ground gateway connected with the access network equipment, and the access network equipment is only connected with one ground gateway; or the service gateway is the gateway with the best signal strength in the N ground gateways, and the access network equipment is connected with the N ground gateways, wherein N is greater than 1, and N is an integer;

and the access network equipment acquires the information of the tracking area according to the information of the service gateway.

Therefore, the access network equipment can ensure the communication quality between the access network equipment and the service gateway by selecting the service gateway, and the information of the tracking area is acquired according to the information of the service gateway and cannot change relative to the ground geographic position of the service gateway, so that the information of the tracking area can accurately represent the tracking area where the terminal is located.

In one possible design, the access network device obtains information of the tracking area, including:

the access network equipment acquires the information of the tracking area according to the first corresponding relation; wherein the first corresponding relationship comprises a corresponding relationship between information of the service gateway and information of the time period.

Therefore, the access network equipment directly determines the information of the tracking area based on the first corresponding relation, such as the ephemeris, so that the calculation amount of the access network equipment is reduced, and the processing flow is simplified. And the determined information of the tracking area comprises the information of the service gateway, and the geographic position of the service gateway is relatively fixed, so that the information of the tracking area can more accurately indicate the position of the terminal.

In one possible design, the access network device sends a broadcast message, including:

in a first time interval, the access network equipment sends a first broadcast message, wherein the first broadcast message comprises information of a service gateway corresponding to the first time interval;

and in a second time interval, the access network equipment sends a second broadcast message, wherein the second broadcast message comprises the information of the service gateway corresponding to the second time interval, and the information of the service gateway in the first broadcast message is different from that in the second broadcast message.

In one possible design, the information of the tracking area further includes information of a sub-area, where the sub-area belongs to a coverage area of a serving gateway of a time period, and the access network device sends the broadcast message, where the method includes:

in a third time period, the access network equipment sends a third broadcast message, wherein the third broadcast message comprises information of a sub-area corresponding to the third time period;

in a fourth time period, the access network device sends a fourth broadcast message, where the fourth broadcast message includes information of a sub-area corresponding to the fourth time period, and the information of the sub-area included in the third broadcast message is different from the information of the sub-area included in the fourth broadcast message.

In a third aspect, an embodiment of the present application provides a communication method, where the method is applied to an access network device or a chip of the access network device, and the method includes: the access network device sends a connection establishment request to the first core network device and receives a connection establishment response from the first core network device. Wherein the connection establishment request includes information of one or more terrestrial gateways to which the first core network device is connected.

Here, the establishment of the communication connection between the first core network device and the access network device is completed through the interaction between the first core network device and the access network device.

In one possible design, the access network device may further perform the following steps:

and the access network equipment acquires the information of the ground gateway from the detected ground gateway synchronous signal.

In this way, the access network device detects the synchronization signal of each ground gateway, and acquires the information of the ground gateway based on the detected synchronization signal of the ground gateway, so as to establish a communication connection with the core network device to which the ground gateway belongs through the ground gateway.

the access network equipment sends a TA updating request to the first core network equipment and receives a TA updating response from the first core network equipment; the TA updating request comprises updated information of the tracking area, the updated information of the tracking area comprises information of a service gateway, the service gateway is one of one or more ground gateways, and the TA updating request is used for requesting to update the corresponding relation between the information of the service gateway and the access network equipment.

Thus, through the processing, the access network device reports the updated service gateway to the first core network device, so that the first core network device updates the corresponding relationship between the service gateway and the access network device, and provides an information basis for the paging process.

the access network equipment acquires the first corresponding relation and determines the information of the current service gateway according to the first corresponding relation so as to acquire the information of the tracking area. Wherein the first corresponding relationship comprises a corresponding relationship between information of the service gateway and information of the time period.

In a fourth aspect, an embodiment of the present application provides a communication method, where the method is applied to a core network device or a chip of the core network device, and the method includes: the first core network device receives the connection establishment request from the access network device and sends a connection establishment response to the access network device. The connection establishment request is used for requesting to establish communication connection between the access network device and the first core network device, and the connection establishment request comprises information of one or more ground gateways connected with the first core network device.

In one possible design, the first core network device may further perform the following steps:

the first core network receives a TA updating request from the access network equipment and sends a TA updating response to the access network equipment; the TA updating request comprises information of a tracking area, the information of the tracking area comprises information of a service gateway, the service gateway comprises a gateway determined from ground gateways connected with access network equipment, and the TA updating request is used for requesting to update the corresponding relation between the information of the service gateway and the access network equipment.

In a possible design of the third aspect or the fourth aspect, the connection establishment request further includes time information, the time information includes information of a time period, and information of a serving gateway to which the access network device is connected at different time periods is different.

In a possible design of the third aspect or the fourth aspect, the connection establishment request further includes information of a sub-region, the time information further includes information of a sub-period, one time period includes one or more sub-periods, the sub-region belongs to a coverage area of a serving gateway of the time period, and different sub-periods correspond to different sub-regions.

In a fifth aspect, an embodiment of the present application provides a communication method, where the method is applied to an access network device or a chip of the access network device, and the method includes: the access network device receives the paging message from the first core network device and broadcasts the paging message. The access network device includes an access network device to which the serving gateway in the sending time tracking area List TA List is connected.

In a sixth aspect, an embodiment of the present application provides a communication method, where the method is applied to a core network device or a chip of the core network device, and the method includes: the first core network device determines the access network device connected with the serving gateway in the tracking area List TA List at the time of sending the paging message, and sends the paging message to the access network device. The tracking area List TA List includes information of tracking areas, and the information of tracking areas includes information of a service gateway.

Here, paging is performed based on an area covered by an access network device to which the gateway in the TA List is connected at a paging time (i.e., a time when the paging message is transmitted). Compared with the prior art, in which paging messages are sent in all cells indicated by the TA List, since information of a tracking area broadcasted by a satellite is always bound to a serving cell and the time of the satellite moves relative to the ground, and a terminal may frequently perform TAU even if the terminal does not move or moves at a low speed, the cell broadcasted by the satellite moves relative to the ground in the prior art, and the position of the terminal is indicated by the cell moving relative to the ground at the time in the prior art, which is poor in accuracy. And since the terminal may frequently perform TAU, the number of cells in the TA List is huge. Thus, the paging message is sent to all cells of the TA List, the paging range is large, and a large paging resource is consumed. The information of the tracking area of the communication method provided by the embodiment of the application comprises the information of the service gateway, and the service gateway is deployed on the ground, and the position of the service gateway is fixed and unchanged, so that the terminal does not need to execute the TAU as long as the terminal does not exceed the coverage of the service gateway even if the satellite moves relative to the ground at any time and the terminal moves at a low speed. Because the frequency of executing TAU by the terminal is reduced in the embodiment of the application, the number of the service gateways in the TA List of the terminal is small, the paging range is narrowed, and the paging resource is saved.

In one possible design, the determining, by the first core network device, an access network device to which a serving gateway in a paging message sending time tracking area List TA List is connected includes:

and the first core network equipment acquires the second corresponding relation and determines access network equipment connected with the service gateway in the paging message sending time TA List according to the second corresponding relation. And the second corresponding relation comprises a corresponding relation between the service gateway and the access network equipment.

Thus, the first core network device may determine the access network device to which the serving gateway in the TA List is connected at the paging message sending time based on the second correspondence between the serving gateway and the access network device updated in real time, so as to send the paging message through the access network device to which the serving gateway in the TA List is connected.

In one possible design, the determining, by the first core network device, the access network device to which the serving gateway in the paging message transmission time tracking area List TA List is connected includes:

and the first core network equipment determines the access network equipment connected with the service gateway in the paging message sending time TA List according to the third corresponding relation. The third corresponding relation comprises information of the time period and a corresponding relation between the access network equipment and the service gateway.

In this way, the first core network device determines the access network device connected to the serving gateway in the TA List according to the third correspondence (information of the time period, correspondence between the access network device and the serving gateway), so as to send the paging message through the access network device connected to the serving gateway in the TA List.

In a possible design, the information about the tracking area further includes information about a sub-area, and the determining, by the first core network device, of the access network device to which the serving gateway in the tracking area List TA List is connected at the paging message sending time includes:

and the first core network equipment determines the access network equipment corresponding to the sub-area in the paging message sending time TA List according to the fourth corresponding relation. The fourth corresponding relationship includes a corresponding relationship between information of the sub-period and information of the access network device and the sub-region, one or more sub-periods constitute a time period, the sub-region belongs to a coverage area of the serving gateway in the constituted time period, and the fourth corresponding relationship is used to indicate: and in different sub-periods, the access network equipment corresponds to a sub-region.

Here, since the area information in the TA List includes: the serving gateway covers a sub-area of the area, and the first core network device determines a sending area of the paging message according to the sub-area information in the TA List, so that the paging range can be reduced, and the paging resource can be saved.

In a seventh aspect, an embodiment of the present application provides a communication apparatus, which may be the terminal in the first aspect. The device includes: communication unit, memory cell and processing unit. The communication unit is used for receiving a broadcast message from the access network equipment, wherein the broadcast message comprises information of a tracking area, and the information of the tracking area comprises information of a service gateway; and the storage unit is used for storing the information of the tracking area.

In a possible design, the processing unit is configured to perform a tracking area update TAU if the information of the tracking area in the broadcast message received by the communication unit is not in the tracking area List TA List of the storage unit.

In a possible design, the processing unit is configured to perform tracking area update TAU if the information about the tracking area with serving gateway granularity received by the communication unit is not in the tracking area List TA List of the storage unit.

In a possible design, the information of the tracking area further includes information of a sub-area, the sub-area belongs to a coverage area of the serving gateway, and the processing unit is configured to perform tracking area update TAU if the information of the tracking area with the granularity of the sub-area received by the communication unit is not in the tracking area List TA List of the storage unit after receiving the broadcast message from the access network device.

In an eighth aspect, an embodiment of the present application provides a communication apparatus, which may be the access network device in the second aspect. The device comprises: a communication unit and a processing unit. The processing unit is used for acquiring information of a tracking area, wherein the information of the tracking area comprises information of a service gateway; a communication unit for transmitting a broadcast message, the broadcast message including information of the tracking area.

In one possible design, the processing unit is configured to obtain information of the tracking area, and includes: for determining a serving gateway; the service gateway is a ground gateway connected with the access network equipment, and the access network equipment is only connected with one ground gateway; or the service gateway is the gateway with the best signal strength in the N ground gateways, and the access network equipment is connected with the N ground gateways, wherein N is greater than 1, and N is an integer;

and the tracking area information is obtained according to the information of the service gateway.

In one possible design, the processing unit is configured to obtain information of the tracking area, and includes: and the tracking area information acquisition module is used for acquiring the information of the tracking area according to the first corresponding relation. Wherein the first corresponding relationship comprises a corresponding relationship between information of the service gateway and information of the time period.

In one possible design, a communication unit for transmitting a broadcast message includes: the first broadcast message is used for sending a first broadcast message in a first time period, and the first broadcast message comprises information of a service gateway corresponding to the first time period;

and the first and second broadcast messages are further configured to send a second broadcast message in a second time period, where the second broadcast message includes information of a serving gateway corresponding to the second time period, and the information of the serving gateway included in the first and second broadcast messages is different.

In one possible design, the information of the tracking area further includes information of a sub-area, and the sub-area belongs to a coverage area of the serving gateway of the time period.

A communication unit for transmitting a broadcast message, comprising: the first broadcast message is used for sending a first broadcast message in a first time period, and the first broadcast message comprises information of a subarea corresponding to the first time period;

and the first terminal is further configured to send a fourth broadcast message in a fourth time period, where the fourth broadcast message includes information of a sub-region corresponding to the fourth time period, and the information of the sub-region included in the third broadcast message is different from the information of the sub-region included in the fourth broadcast message.

In a ninth aspect, an embodiment of the present application provides a communication apparatus, which may be the access network device in the third aspect. The device includes: a communication unit and a processing unit. The communication unit is configured to send a connection establishment request to a first core network device, where the connection establishment request is used to request establishment of a communication connection between the access network device and the first core network device, and the connection establishment request includes information of one or more terrestrial gateways to which the first core network device is connected; and is further configured to receive a connection setup response from the first core network device.

In one possible design, the processing unit is configured to obtain information of the terrestrial gateway from the detected terrestrial gateway synchronization signal.

In a possible design, the communication unit is further configured to send a TA update request to the first core network device; the TA updating request comprises updated information of the tracking area, the updated information of the tracking area comprises information of a service gateway, the service gateway is one of one or more ground gateways, and the TA updating request is used for requesting to update the corresponding relation between the information of the service gateway and the communication device;

and the communication unit is further used for receiving the TA update response from the first core network device.

In one possible design, the processing unit is configured to obtain and determine information of a current serving gateway according to the first corresponding relationship to obtain information of the tracking area. Wherein the first corresponding relationship comprises a corresponding relationship between information of the service gateway and information of the time period.

In a tenth aspect, an embodiment of the present application provides a communication apparatus, which may be the core network device in the fourth aspect. The device includes: a communication unit. The communication unit is configured to receive a connection establishment request from an access network device, where the connection establishment request is used to request establishment of a communication connection between the access network device and a first core network device, and the connection establishment request includes information of one or more terrestrial gateways to which the first core network device is connected; and is further configured to send a connection setup response to the access network device.

In a possible design, the communication unit is further configured to receive a TA update request from the access network device, and send a TA update response to the access network device; the TA updating request comprises information of a tracking area, the information of the tracking area comprises information of a service gateway, the service gateway comprises a gateway determined from ground gateways connected with access network equipment, and the TA updating request is used for requesting to update the corresponding relation between the information of the service gateway and the access network equipment.

In a possible design of the ninth aspect or the tenth aspect, the connection establishment request further includes time information, the time information includes information of a time period, and the information of the serving gateway to which the access network device is connected is different for different time periods.

In a possible design of the ninth aspect or the tenth aspect, the connection establishment request further includes information of a sub-region, the time information further includes information of a sub-period, one time period includes one or more sub-periods, the sub-region belongs to a coverage area of a serving gateway of the time period, and different sub-periods correspond to different sub-regions.

In an eleventh aspect, an embodiment of the present application provides a communication apparatus, which may be the access network device in the fifth aspect. The device comprises: a communication unit. The communication unit is used for receiving the paging message from the first core network device and broadcasting the paging message. The access network equipment comprises the access network equipment connected with the service gateway in the sending time tracking area List TA List.

In a twelfth aspect, an embodiment of the present application provides a communication apparatus, which may be the core network device in the sixth aspect. The device comprises: a communication unit and a processing unit. The processing unit is configured to determine an access network device to which a serving gateway in a paging message sending time tracking area List TA List is connected, and the communication unit is configured to send a paging message to the access network device. The tracking area List TA List includes information of tracking areas, and the information of tracking areas includes information of a service gateway.

In one possible design, a processing unit configured to determine an access network device to which a serving gateway in a paging message transmission time tracking area List TA List is connected includes: and the second mapping unit is configured to obtain the second mapping relationship, and determine, according to the second mapping relationship, the access network device to which the serving gateway in the paging message sending time TA List is connected. And the second corresponding relation comprises a corresponding relation between the service gateway and the access network equipment.

In one possible design, a processing unit configured to determine an access network device to which a serving gateway in a paging message transmission time tracking area List TA List is connected includes: and the access network device is used for determining the access network device connected with the serving gateway in the paging message sending time TA List according to the third corresponding relation. The third corresponding relation comprises information of the time period and a corresponding relation between the access network equipment and the service gateway.

In one possible design, the information of the tracking area further includes information of a sub-area, and the processing unit is configured to determine an access network device to which a serving gateway in the tracking area List TA List is connected at a paging message sending time, and includes: and the access network device is used for determining the access network device corresponding to the sub-area in the paging message sending time TA List according to the fourth corresponding relation. The fourth corresponding relationship includes a corresponding relationship between information of the sub-period and information of the access network device and the sub-region, one or more sub-periods constitute a time period, the sub-region belongs to a coverage area of the serving gateway in the constituted time period, and the fourth corresponding relationship is used to indicate: and accessing the sub-areas corresponding to the network equipment in different sub-periods.

In a thirteenth aspect, the present application provides a communication apparatus, configured to implement the function of the terminal in the foregoing first aspect, or configured to implement the function of the access network device in the foregoing second aspect, third aspect, or fifth aspect, or configured to implement the function of the core network device in the foregoing fourth aspect or sixth aspect.

In a fourteenth aspect, an embodiment of the present application provides a communication apparatus having a function of implementing the communication method in any one of the above aspects. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the functions described above.

In a fifteenth aspect, a communication device is provided, comprising: a processor and a memory; the memory is used for storing computer-executable instructions, and when the communication device runs, the processor executes the computer-executable instructions stored by the memory to enable the communication device to execute the communication method according to any one of the above aspects.

In a sixteenth aspect, a communication apparatus is provided, including: a processor; the processor is configured to be coupled to the memory, and after reading the instructions in the memory, execute the communication method according to any one of the above aspects according to the instructions.

A seventeenth aspect provides a computer-readable storage medium having instructions stored therein, which when run on a computer, cause the computer to perform the communication method of any of the above aspects.

In an eighteenth aspect, there is provided a computer program product containing instructions which, when run on a computer, cause the computer to perform the communication method of any of the above aspects.

In a nineteenth aspect, there is provided circuitry comprising processing circuitry configured to perform the communication method of any one of the above aspects.

In a twentieth aspect, there is provided a chip comprising a processor, a processor coupled to a memory, the memory storing program instructions that, when executed by the processor, implement the communication method of any one of the preceding aspects.

In a twenty-first aspect, a communication system is provided, where the communication system includes the terminal in any of the above aspects, the access network device in any of the aspects, and the core network device in any of the aspects.

The technical effects brought by any one of the design manners in the second aspect to the twenty-first aspect may refer to the technical effects brought by different design manners in the first aspect, and are not described herein again.

Drawings

Fig. 1 is a schematic diagram of an NTN system architecture according to an embodiment of the present application;

fig. 2 is a schematic diagram of an NTN system architecture according to an embodiment of the present application;

fig. 3 is a schematic diagram of an NTN system architecture according to an embodiment of the present application;

fig. 4 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 5 is a schematic scene diagram of a communication method according to an embodiment of the present application;

fig. 6 is a scene schematic diagram of a communication method according to an embodiment of the present application;

fig. 7 is a schematic scene diagram of a communication method according to an embodiment of the present application;

fig. 8 is a scene schematic diagram of a communication method according to an embodiment of the present application;

fig. 9 is a schematic view of a scenario of a communication method according to an embodiment of the present application;

fig. 10 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 11 is a schematic view of a scenario of a communication method according to an embodiment of the present application;

fig. 12 is a schematic scene diagram of a communication method according to an embodiment of the present application;

fig. 13 is a schematic view of a scenario of a communication method according to an embodiment of the present application;

fig. 14 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 15 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 16 is a flowchart of a communication method according to an embodiment of the present application;

fig. 17 is a flowchart of a communication method according to an embodiment of the present application;

fig. 18 is a flowchart of a communication method according to an embodiment of the present application;

fig. 19 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 20 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 21 is a flowchart of a communication method according to an embodiment of the present application;

fig. 22 is a flowchart of a communication method according to an embodiment of the present application;

fig. 23 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 24 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 25 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 26 is a flowchart of a communication method according to an embodiment of the present application;

fig. 27 is a flowchart of a communication method provided in an embodiment of the present application;

fig. 28 is a flowchart of a communication method according to an embodiment of the present application;

fig. 29 is a flowchart of a communication method according to an embodiment of the present application;

fig. 30 is a schematic view of a scenario of a communication method according to an embodiment of the present application;

fig. 31 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 32 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

The terms "first" and "second" and the like in the description and drawings of the present application are used for distinguishing different objects or for distinguishing different processes for the same object, and are not used for describing a specific order of the objects. Furthermore, the terms "including" and "having," and any variations thereof, as referred to in the description of the present application, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements but may alternatively include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. It should be noted that in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described herein as "exemplary" or "e.g.," is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word "exemplary" or "such as" is intended to present relevant concepts in a concrete fashion.

The communication method provided by the embodiment of the application can be applied to an NTN system or other similar systems, for example, can be applied to other communication systems in which a terminal frequently executes TAU.

First, taking application to an NTN system as an example, an NTN system architecture related to the embodiment of the present application is given. In the embodiment of the present application, the NTN system architecture includes an access network device, a terminal communicating with the access network device, and a core network device. All or part of the functional modules of the access network equipment can be deployed in an idle platform or a satellite or other forms of communication equipment in high altitude. The terminal and the access network equipment are communicated through a wireless interface, the access network equipment is communicated with the core network equipment through a ground gateway, and the core network equipment and the ground gateway are deployed on the ground.

The NTN system architecture may be applied to the current Long Term Evolution (LTE) or LTE advanced (LTE-a) system, and may also be applied to a currently established fifth generation mobile communication technology (5-generation, 5G) network or other future networks. Of course, the method and the device may also be applied to a system of LTE and 5G hybrid networking, or other systems, and this is not particularly limited in this embodiment of the present application. In different networks, the core network device, the access network device, and the terminal in the NTN system architecture may correspond to different names, and those skilled in the art will understand that the names do not limit the devices themselves.

The core network device referred to in the embodiments of the present application is a device deployed in a core network to provide a service for a terminal. In systems employing different radio access technologies, the names of core network devices with similar wireless communication capabilities may differ. For example, when the communication method of the embodiment of the present application is applied to a 5G system, the core network device may be an access and mobility management function (AMF), and when the communication method is applied to an LTE system, the core network device may be a Mobility Management Entity (MME). For convenience of description only, in the embodiments of the present application, the above-mentioned devices capable of providing services for the terminal are collectively referred to as core network devices.

An access network device is a device deployed in a radio access network to provide wireless communication functions. Optionally, the access network device according to the embodiment of the present application includes, for example and without limitation, macro base stations, micro base stations (also referred to as small stations), relays, Transmission Reception Points (TRPs), next generation network nodes (g Node bs, gnbs), evolved Node bs (ng-enbs) connected to a next generation core network, and the like in various forms, and may further include a radio access network device of a non-third generation partnership project (3 GPP) system, such as a Wireless Local Area Network (WLAN) access device. It has been noted above that all or some of the functional modules of the access network equipment may be deployed on an off-the-air platform or satellite, or other form of communication equipment deployed aloft. Accordingly, an access network device may refer to an off-the-shelf platform, or satellite, or other similar device that accesses terminals to core network equipment.

The terminal is mainly used for receiving or sending data. Alternatively, the terminal involved in the embodiments of the present application may include, for example but not limited to, various handheld devices, vehicle-mounted devices, wearable devices, computing devices, or other processing devices connected to a wireless modem with wireless communication capability; a subscriber unit (subscriber unit), a cellular phone (cellular phone), a smart phone (smart phone), a wireless data card, a Personal Digital Assistant (PDA) computer, a tablet computer, a handheld device (hand), a laptop computer (laptop computer), a Machine Type Communication (MTC) terminal (terminal), a User Equipment (UE), and the like may also be included.

Referring to fig. 1 and 2, an NTN system architecture is shown, respectively. The NTN system includes an access network device and a core network device. The access network equipment may be deployed on an off-the-shelf platform. The empty platform may comprise at least one of: satellite, drone, or hot air balloon. The NTN system also includes a ground gateway and a Data Network (DN). The terminal communicates with the access network equipment over an interface, for example, a new radio-air interface between nodeb and user equipment (NR-Uu). The access network equipment communicates with the ground gateway over an interface, such as an NG over radio interface (NG over SRI). The ground gateway communicates with the core network device via an interface, for example, a Next Generation (NG) interface. The core network device may be connected to only one ground gateway, and in this case, the access network device may be connected to the core network device through one ground gateway, as shown in fig. 1. The core network device may be connected to more than one ground gateway, and at this time, the access network device may be connected to the core network device through any one of the more than one ground gateways, as specifically shown in fig. 2 (fig. 2 only shows 2 ground gateways). The core network device may communicate with an entity or network element, etc. in a Data Network (DN) over an interface, such as an N6 interface.

It should be noted that, the above only lists some ways of communication between network elements, and other network elements may also communicate through some connection ways, which is not described herein again in this embodiment of the present application.

Referring to fig. 3, fig. 3 shows another NTN system architecture. The NTN system comprises access network equipment and core network equipment. The access network device includes a Distributed Unit (DU) and a Central Unit (CU). Referring to fig. 3, the access network device may be a next generation network Node (gNB). Optionally, the gNB may include a next generation network Node B-distributed unit (gNB-DU) and a next generation network Node center unit (gNB-CU). In one possible example, the gNB-DUs are deployed in a satellite and the gNB-CUs are deployed on the ground. The NTN system may also include a terrestrial gateway and a DN. The terminal communicates with the gNB-DU through a new radio-Uu (NR-Uu) and the gNB-DU communicates with the gNB-CU through a ground gateway, wherein the gNB-DU communicates with the ground gateway through a satellite radio interface (F1over satellite radio interface, F1over SRI). The gNB-CU communicates with the core network device through a Next Generation (NG) interface. The core network device may communicate with a network element or entity in a Data Network (DN) through an N6 interface.

It should be emphasized that the NTN system architecture of the embodiment of the present application may include multiple access network devices and multiple core network devices, and fig. 1, fig. 2, and fig. 3 only illustrate one access network device and one core network device by way of example. In fig. 1, 2 and 3, the dotted lines represent wireless communication connections, and the solid lines represent wired communication connections.

The NTN system architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not constitute a limitation on the technical solution provided by the embodiment of the present application. As can be known to those skilled in the art, with the evolution of network architecture and the emergence of new service scenarios, the technical solution provided in the embodiments of the present application is also applicable to similar technical problems.

The following specifically explains the communication method provided in the embodiment of the present application.

It should be noted that, in the following embodiments of the present application, the names of messages between network elements or the names of parameters in messages, etc. are only examples, and other names may also be used in specific implementations, which are described in a unified manner herein and will not be described again below.

The embodiment of the application provides a communication method, which is applied to the process of position management of a terminal. Referring to fig. 4, the communication method includes the steps of:

s401, the access network equipment acquires the information of the tracking area.

The access network device may be mounted on a satellite. For example, a base station installed in a satellite, a DU installed in a satellite, or a DU and CU installed in a satellite.

Wherein the information of the tracking area includes information of a serving gateway. As a possible implementation, one gateway may be selected from the plurality of ground gateways as the serving gateway. Wherein the geographical position of the ground gateway is fixed. Accordingly, the information of the serving gateway may be referred to as information (ground gateway information) of the ground gateway. The service gateway is accessed by the access network equipment and can provide services for the access network equipment. The information of the service gateway may be a name of the service gateway, an Identity (ID) of the service gateway, or other forms. For example, if the method of the embodiment of the present application is applied to the system shown in fig. 1 or fig. 2, the serving gateway refers to a gateway that provides a service for a base station (mounted on a satellite). If the method of the embodiment of the present application is applied to the system shown in fig. 3, the serving gateway refers to a gateway that provides services for a gNB-DU (satellite-mounted). It is easy to understand that when the location of the access network device changes, the serving gateway of the access network device may also change, and accordingly, the information of the serving gateway (such as the name of the serving gateway) changes, and the information of the tracking area changes accordingly.

S402, the access network equipment sends the broadcast message. Accordingly, the terminal receives the broadcast message from the access network device.

Wherein the broadcast message includes information of the tracking area.

For a certain access network device, the service gateway is constantly changed, so that the access network device broadcasts information of different tracking areas along with the change of the operation track.

S403, the terminal stores the information of the tracking area.

The terminal stores the received tracking area information, such as serving gateway information, in the TA List, so as to perform subsequent location management and paging, and provide information support for the location management and paging process. For example, the information of the serving gateway includes GW1-ID, and the terminal stores the tracking area information including GW1-ID after receiving the tracking area information.

According to the communication method provided by the embodiment of the application, the access network equipment acquires the information of the tracking area and sends the broadcast message with the information of the tracking area, and the terminal stores the information of the tracking area. Wherein the information of the tracking area includes information of a serving gateway. Compared with the prior art, the communication method of the embodiment of the application manages according to the information of the service gateway, because the service gateway is deployed on the ground and the position of the service gateway is fixed, when the service cell of the terminal changes, the service gateway to which the terminal belongs is unlikely to change, and the terminal is prevented from frequently executing the TAU.

The service gateway to which the terminal belongs according to the embodiment of the present application means that the terminal is connected to the core network device through the service gateway. The description is unified here and will not be described in detail below.

It is easily understood that, at a certain moment, after the terminal receives the broadcast message (the broadcast message includes the information of the tracking area) from the access network device, the terminal performs:

s404, if the tracking area information in the received broadcast message is not in the TA List of the terminal, the terminal executes TAU.

On the contrary, if the tracking area information in the received broadcast message is in the TA List of the terminal, the terminal does not perform TAU.

The information of the tracking area may include information of a serving gateway, and may further include information of the serving gateway and information of a sub-area.

As a possible implementation manner, if the information of the tracking area takes the serving gateway as the granularity, the specific implementation process of the terminal determining whether to execute the TAU may include the following steps:

On the contrary, if the information of the tracking area with the serving gateway as the granularity is in the TA List of the terminal, the terminal does not need to execute the TAU.

Exemplarily, referring to fig. 5, it is assumed that the TA List of the terminal includes information of the following tracking areas: GW1-ID, GW2-ID, GW3-ID, then after the terminal receives the tracking area information broadcast by gNB1 (including the serving gateway information, namely GW1-ID), the terminal knows that the tracking area information is in the TA List, then the terminal does not perform TAU. Moreover, when the terminal moves, although the location of the terminal changes, the core network device can know the location of the terminal as long as the terminal does not exceed the dashed oval area (the dashed oval area represents the coverage area of the serving gateway GW1), and thus, the terminal does not need to perform TAU.

For example, referring to fig. 6, the terminal may move at a low speed and move from the coverage of the gNB1 to the coverage of the gNB2, in this case, even if the access network device accessed by the terminal changes and the serving cell (cell) changes, the terminal does not exceed the coverage of the serving gateway GW1, that is, the information of the tracking area is still in the TA List of the terminal, and the terminal does not need to perform TAU.

In one scenario, referring to fig. 7 and 8, as the gNB1 moves from right to left in the figure, the broadcasted tracking area information includes GW1-ID, and if the gNB1 continues to move from right to left, the tracking area information broadcasted by the gNB1 includes GW 2-ID. Similarly, during movement of gNB2 from right to left in the figure, the tracking area information broadcast includes GW1-ID, and if gNB2 continues to move from right to left, the tracking area information broadcast by gNB2 includes GW 2-ID. It can be seen that the information of the tracking area received by UE1 has ping-pong phenomenon, that is, UE1 may receive GW1-ID and GW2-ID broadcasted by gNB1 first, and then receive GW1-ID and GW2-ID broadcasted by gNB2, and the received information of the tracking area is alternated between GW1-ID and GW 2-ID. In conjunction with fig. 7 and 8, in the process that the gNB1 moves from right to left in the figure, the information in the TA List corresponding to the terminal UE1 is updated as follows: GW1-ID, GW 2-ID. Subsequently, even if the ping-pong phenomenon occurs during the movement of the gNB2 from right to left in the figure, the updated TA List is updated by the GW1-ID and the GW2-ID broadcasted by the gNB1, so that the information of the tracking area broadcasted by the gNB2 is ensured to be in the updated TA List (including the GW1-ID and the GW2-ID), and the terminal does not need to execute TAU. That is, according to the above method, when the ping-pong phenomenon occurs, the execution frequency of the TAU can be reduced, and the power consumption of the terminal can be reduced.

In this way, the terminal can determine whether to perform TAU only by determining whether the currently received tracking area information exists in the TA List. As can be understood from the above method, when the serving cell of the terminal or the access network device to which the terminal is accessed changes, the serving gateway to which the terminal belongs does not necessarily change, and therefore, the tracking area information does not necessarily change. Thus, the tracking area information does not exceed the range indicated by the TA List, and the terminal does not perform TAU. Compared with the prior art that the serving cell changes to cause the frequent execution of the TAU, the method can greatly reduce the times of the terminal executing the TAU and avoid the terminal frequently executing the TAU.

According to the communication method provided by the embodiment of the application, after the terminal receives the information of the tracking area, the information of the tracking area comprises the information of the service gateway, and the terminal can determine whether to execute the TAU only by judging whether the information of the tracking area with the service gateway as the granularity is in the TA List of the terminal, so that the operation process of the terminal is greatly simplified.

As another possible implementation manner, if the information of the tracking area uses a sub-area of the serving gateway as a granularity, the specific implementation process of the terminal determining whether to execute the TAU may include the following steps:

On the contrary, if the information of the tracking area with the sub-area as the granularity is in the TA List of the terminal, the terminal does not need to execute the TAU.

Illustratively, referring to fig. 9, the dashed oval area represents the coverage area of the serving gateway GW1, the right half of the dashed oval area represents sub-area 1 (which may be identified as "-1") of the serving gateway GW1, and the left half of the dashed oval area represents sub-area 2 (which may be identified as "-2") of the serving gateway GW 1. The information of the tracking area in the TA List of the terminal includes: GW 1-2-ID. If the terminal receives information of a certain tracking area, the information of the tracking area includes GW1-2-ID as shown in fig. 9. At this time, since the information GW1-2-ID of the sub-area is in the TA List of the terminal, the terminal does not need to perform TAU. As the terminal moves from left to right in the figure, it enters another sub-area (sub-area 1), and if the terminal receives information of another tracking area, the information of the tracking area includes GW 1-1-ID. At this time, since the information GW1-1-ID of the sub-area is not in the TA List of the terminal, the terminal needs to execute TAU, so that the core network device acquires the tracking area where the terminal is currently located.

Here, the terminal only needs to determine whether to execute TAU by determining whether currently received tracking area information with sub-area as granularity exists in the TA List. When the terminal is subjected to position management, the coverage of the service gateway in which the terminal is located at the current moment can be determined, and the sub-area of the coverage area of the service gateway in which the terminal is located can also be determined. Therefore, the position range of the terminal is smaller, and the position of the terminal can be indicated more accurately.

There are various specific implementation manners of the step of "S401, the access network device obtains the information of the tracking area". The following examples are given.

As a possible implementation manner, referring to fig. 10, the obtaining, by the access network device, the information of the tracking area may include the following steps:

s101, the access network equipment determines a service gateway.

Specifically, the access network device determines the serving gateway according to the ground gateway to which the access network device is connected.

In one possible design, the information for each terrestrial gateway to which the access network device is connected is derived from the first correspondence. The first correspondence may include a correspondence between information of the service gateway and information of the time period. The first corresponding relation may specifically be an ephemeris, or a track time table, etc. The access network device may store the first corresponding relationship in advance, or acquire the first corresponding relationship from the first core network device when the access network device needs to determine the serving gateway.

Illustratively, at a certain time, the access network device is capable of connecting N terrestrial gateways, where N is an integer. If N is 1, the access network device takes the one ground gateway as a serving gateway, and if N is greater than 1, the access network device selects the ground gateway with the best signal strength from the N ground gateways as the serving gateway, so as to ensure the communication quality.

In another possible design, the information for each terrestrial gateway to which the access network device is connected is derived from the synchronization signal for each terrestrial gateway. The synchronization signal of the ground gateway carries information of the ground gateway, such as an identifier of the ground gateway.

For example, at a certain time, the access network device may detect only a synchronization signal of one terrestrial gateway, obtain information of one terrestrial gateway from the detected synchronization signal, and establish a communication connection with the first core network device through the terrestrial gateway, where the access network device connects to only one terrestrial gateway, and then uses the terrestrial gateway as a serving gateway for communication.

At another time, the access network device has determined the serving gateway and the access network device also detects synchronization signals from other terrestrial gateways, then a link is added with the corresponding terrestrial gateway. If the access network device also detects a signal from the terrestrial gateway GW2, then a link is added with the terrestrial gateway GW 2. When the signal quality of the ground gateway GW2 meets the switching condition of the service gateway, the access network equipment switches the service gateway. For example, the handover condition of the serving gateway may include: there is a certain terrestrial gateway with a signal quality better than that of the current serving gateway. The handover condition of the serving gateway may also include: within the time threshold (which can be flexibly set according to the application scenario), the signal quality of a certain ground gateway is better than that of the current service gateway. The handover condition of the serving gateway may further include: the signal quality of the current serving gateway is below a signal quality threshold (which may be set otherwise depending on the application scenario).

S102, the access network equipment acquires the information of the tracking area according to the information of the service gateway.

Illustratively, the access network device may use the identification of the serving gateway (such as "GW 1-ID" or "GW 2-ID") as the information of the tracking area. Or the access network device may use the identification of the serving gateway (such as "GW 1-ID" or "GW 2-ID") as part of the information for the tracking area.

Therefore, the access network equipment can ensure the communication quality between the access network equipment and the ground gateway by selecting the service gateway, and the information of the tracking area is acquired according to the information of the service gateway and cannot change relative to the ground geographical position of the service gateway, so that the information of the tracking area can accurately represent the tracking area where the terminal is located.

As follows, with reference to the scene diagrams of fig. 11, fig. 12, and fig. 13, a detailed description is given to a possible implementation manner of "the access network device selects the serving gateway through the signal strength to acquire the information of the tracking area":

referring to fig. 11, in the first time period, the signal quality of ground gateway GW1 is better than that of ground gateway GW2, ground gateway GW1 serves as a serving gateway for access network device gNB1, and in fig. 11, a solid line connection is used between access network device gNB1 and ground gateway GW1 to indicate that access network device gNB1 uses ground gateway GW1 as a serving gateway, at this time, the broadcast message sent by access network device gNB1 includes information of a tracking area, and the information of the tracking area includes an identifier (GW1-ID) of ground gateway GW 1. The access network device also detects a synchronization signal from another, e.g., terrestrial gateway GW2, and adds a link with the terrestrial gateway GW 2. in fig. 11, the access network device gNB1 is connected with the terrestrial gateway GW2 by a dashed line to indicate that the access network device gNB1 has added a link with the terrestrial gateway GW 2.

Referring to fig. 12, as the access network device gNB1 continues to move relatively to the ground, the separation distance between the access network device gNB1 and the two ground gateways (GW1 and GW2) also changes. When the access network device detects that the signal quality of the terrestrial gateway GW2 satisfies the handover condition of the serving gateway, it indicates that the terrestrial gateway GW2 can serve as the serving gateway of the access network device gNB 1. In fig. 12, the access network device gNB1 and the terrestrial gateway GW1 and the terrestrial gateway GW2 are connected by solid lines, which indicates that the access network device gNB1 still uses the terrestrial gateway GW1 as a serving gateway, and the terrestrial gateway GW2 satisfies a handover condition of the serving gateway, and can be used as a serving gateway of the access network device gNB 1. The state shown in fig. 12 is a state where the access network device gNB1 has not performed a serving gateway handover, and the information of the tracking area in the broadcast message sent by the access network device gNB1 still includes the identity of the terrestrial gateway GW1 (GW 1-ID).

Referring to fig. 13, the access network device gNB1 performs service gateway switching to switch the service gateway from the terrestrial gateway GW1 to the terrestrial gateway GW 2. In fig. 13, the access network device gNB1 and the terrestrial gateway GW2 are connected by a solid line to indicate that the access network device gNB1 uses the terrestrial gateway GW2 as a serving gateway, and at this time, the information of the tracking area in the broadcast message sent by the access network device gNB1 includes an identifier (GW2-ID) of the terrestrial gateway GW 2. The access network device gNB1 and the terrestrial gateway GW1 are connected by a dashed line to indicate that the link between the access network device gNB1 and the terrestrial gateway GW1 is not deleted.

As another possible implementation manner, referring to fig. 14, the obtaining, by the access network device, the information of the tracking area may include the following steps:

s141, the access network equipment acquires the first corresponding relation.

Wherein the first corresponding relationship comprises a corresponding relationship between information of the service gateway and information of the time period. The first correspondence may indicate: a serving gateway to which the access network device is connected at different time periods. And the service gateway corresponding to each time period provides service for the access network equipment. For example, ephemeris, track schedule, etc. may include a first correspondence. The access network device may store the first corresponding relationship in advance, or acquire the first corresponding relationship from the first core network device when the access network device needs to determine the serving gateway.

And S142, the access network equipment determines the information of the current service gateway according to the first corresponding relation so as to acquire the information of the tracking area.

As another possible implementation manner, referring to fig. 15, the obtaining, by the access network device, the information of the tracking area may include the following steps:

and S151, the access network equipment acquires the ephemeris.

Wherein, the ephemeris includes the time when the access network device accesses the service gateway.

Exemplary ephemeris may include: each of the one or more service gateways provides one or more of a service time, a service-out time, a service duration, and an orbital period of the satellite for the satellite. Wherein, the time when the service gateway provides service for the satellite can be understood as the time when the satellite accesses the gateway. A serving gateway going to service means that the satellite is away from the gateway, so the serving gateway no longer provides service to the satellite. The duration between the time a satellite accesses a serving gateway and the time the satellite leaves the gateway is referred to as the service duration for the gateway serving the satellite. The satellite orbit period refers to the time required for a satellite to orbit the earth one week. Illustratively, table 1 is a possible ephemeris, where each ground station corresponds to a ground gateway, and each ground gateway has a core network ID to which it belongs.

TABLE 1

Of course, more or less information than in table 1 may be included in the ephemeris, and the embodiments of the present application do not limit the specific implementation of the ephemeris.

S152, the access network equipment determines the information of the tracking area according to the ephemeris.

Specifically, the access network device determines the information of the tracking area according to the time when the access network device accesses the service gateway.

Wherein the information of the tracking area includes information of the service gateway. The information of the service gateway may include, for example and without limitation, an identification, a name, etc. of the service gateway.

In the embodiment of the present application, for example, taking the satellite corresponding to the chinese station in table 1 as an example, the orbital period of the satellite surrounding the earth for one circle is 79200s, and the spatial position of the satellite is different at different time periods within the orbital period, for example, assuming that the satellite is located above the chinese area at 12:00-13:00, as inferred from the above ephemeris, at 17: 00-18:00, the satellite is over the european area. When the satellite is in the space above the china area, the satellite accesses the ground gateway deployed by the china station, and accordingly, the information of the tracking area determined by the satellite may include, for example, an identifier (X) of the ground gateway deployed by the china station. When the satellite is empty on a european area, the information of the tracking area may include an identification (Y) of the terrestrial gateway deployed in the european area. It can be understood that the satellite can determine which time period the satellite is in at the current time based on the time of the satellite accessing different service gateways in the ephemeris, so as to know which service gateway is accessed, and further know the information of the tracking area.

Therefore, the access network equipment directly determines the information of the tracking area based on the first corresponding relation between the information of the service gateway and the information of the time period, such as an ephemeris, so that the calculation amount of the access network equipment is reduced, and the processing flow is simplified. And the determined information of the tracking area comprises the information of the service gateway, and the geographic position of the service gateway is relatively fixed, so that the information of the tracking area can more accurately indicate the position of the terminal.

The service gateway is used as the granularity of the tracking area information, and further, the granularity of the tracking area information can be further refined. Specifically, for a certain serving gateway, the access network device divides a time period to which the current time information belongs, to obtain one or more sub-time periods, where each sub-time period corresponds to one sub-area, and each sub-area belongs to a coverage area of the serving gateway corresponding to the time period. At this time, the information of the tracking area broadcasted by the access network device includes information of the serving gateway and information of the sub-area. As such, different tracking area information may include the same serving gateway information and different sub-area information. Alternatively, the different tracking area information may include different serving gateway information and different sub-area information.

There are various specific implementation manners of the step of "S402, sending the broadcast message by the access network device". The following examples are given. As a first possible implementation manner, when a serving gateway included in the information of the tracking area changes, the access network device directly sends different broadcast messages.

The access network equipment takes the ground gateway with the best signal strength as the information of the tracking area, and directly broadcasts a broadcast message comprising the information of the tracking area. Accordingly, the terminal receives the broadcast message from the access network device.

As a second possible implementation, with the serving gateway as the granularity of the information of the tracking area, the access network device sends different broadcast messages according to the time period.

Referring to fig. 16, a specific implementation process of the access network device for sending the broadcast message may include the following steps:

s161, in the first time interval, the access network equipment sends the first broadcast message.

Accordingly, the first terminal receives the first broadcast message from the access network device.

The first broadcast message includes information of a first tracking area, and the information of the first tracking area includes information of a first service gateway corresponding to a first time period. The first terminal is a terminal within a coverage area of the first serving gateway.

And S162, in a second time interval, the access network equipment sends a second broadcast message.

Accordingly, the second terminal receives the second broadcast message from the access network device.

The second broadcast message includes information of a second tracking area, and the information of the second tracking area includes information of a second service gateway corresponding to a second time period. The second terminal is a terminal within the coverage area of the second serving gateway. The first serving gateway is different from the second serving gateway.

For example, based on the ephemeris table, as shown in table 1, in the period from 12:00 to 13:00, the satellite is located over the china area, and then the satellite accesses the terrestrial gateway deployed in the china station, and the information of the tracking area broadcast by the satellite may include, for example, the identifier (X) of the terrestrial gateway deployed in the china station.

As can be inferred from the above ephemeris, at 17: 00-18:00, the satellite is over the european area, the satellite broadcasts to the terminals, and the information of the tracking area may include the identity (Y) of the terrestrial gateways deployed in the european area.

Here, the access network device only sends different broadcast messages according to time, so that the terminal determines whether to execute the TAU after receiving the broadcast messages, thereby facilitating subsequent location management of the terminal.

As a third possible implementation manner, further, the granularity of the tracking area information is refined, and the tracking area information includes information of the serving gateway and information of the sub-area. Specifically, each time period corresponds to one serving gateway. The time periods are divided, each time period comprising one or more sub-periods. The coverage area of each serving gateway includes one or more sub-areas, one sub-area for each sub-period. The access network equipment sends different broadcast messages according to the sub-time period. The different broadcast messages may be broadcast messages including information of different service gateways, or broadcast messages including information of the same service gateway and information of different sub-areas.

Referring to fig. 17, the information of the tracking area includes information of the third serving gateway and information of the first sub-area, and the access network device sends different broadcast messages according to the time information, specifically, the broadcast messages may be corresponding to different sub-areas of the same serving gateway, or corresponding to the same sub-area of different serving gateways, or corresponding to different sub-areas of different serving gateways. The specific implementation process of S402 may include the following steps:

and S171, in the third time interval, the access network equipment sends a third broadcast message.

Correspondingly, the third terminal receives a third broadcast message broadcasted from the access network equipment.

Wherein the third broadcast message includes information of a third tracking area. The information of the third tracking area includes information of a third serving gateway and information of a third sub-area corresponding to the third time period. The third time period is a partial time period of a time period corresponding to the information of the serving gateway in the third broadcast message. The third terminal is a terminal in a third subregion in the third broadcast message.

And S172, in the fourth time interval, the access network equipment sends a fourth broadcast message.

Correspondingly, the fourth terminal receives a fourth broadcast message broadcasted from the access network equipment.

Wherein the fourth broadcast message includes information of a fourth tracking area. The information of the fourth tracking area includes information of a serving gateway and information of a sub-area corresponding to the fourth time period, and may specifically include information of a third serving gateway and information of a second sub-area, may also include information of a fourth serving gateway and information of a first sub-area, and may also include information of a fourth serving gateway and information of a second sub-area. The fourth time period is a partial time period of a time period corresponding to the information of the serving gateway in the fourth broadcast message. The fourth terminal is a terminal within a sub-region in the fourth broadcast message.

Illustratively, referring to fig. 9, the serving gateway of the access network device gNB1 is a gateway GW 1. The coverage area of the gateway GW1 may be divided into two sub-areas according to the above-mentioned ephemeris: subregion 1 and subregion 2. Wherein the identification of sub-region 1 may be "-1" and the identification of sub-region 2 may be "-2". The dashed oval area of the right half is subregion 1 and the dashed oval area of the left half is subregion 2. And in the time period of 10: 00-10: 30, the access network equipment (gNB1) enters the subregion 1. In this way, in a range from 10:00 to 10:30, the access network device gNB1 broadcasts information of the third tracking area, where the information of the third tracking area includes information of a serving gateway (for example, "GW 1") and information of a sub-area 1 (for example, "1" of the sub-area 1), and a format of the information of the third tracking area may specifically be GW1-1-ID (other formats are not excluded). In a time period of 10:30 to 11:00, the access network device gNB1 enters sub-area 2, and the access network device gNB1 sends information of a fourth tracking area to the terminal, where the information of the fourth tracking area includes information of a serving gateway (for example, "GW 1") and information of sub-area 2 (for example, "2" of the identifier of sub-area 2), and the information of the fourth tracking area may specifically be GW 1-2-ID.

Here, the time period corresponding to the serving gateway is divided, and when the access network device enters different sub-areas (for example, an oval area with a dotted solid line on the left side in fig. 9) at different times, the broadcasted information of the tracking area further includes information of the sub-areas. Subsequently, when the location management is performed on the terminal, it can be determined which serving gateway the access network device accesses at the current time, and it can also be determined which sub-area of the coverage area of the serving gateway the broadcast message sent by the access network device can reach, so as to perform more accurate location management on the terminal.

The embodiment of the application also provides a communication method, which is applied to the process of performing communication connection management on the access network equipment and the core network equipment. Referring to fig. 18, the communication method includes the steps of:

and S1800, the access network equipment acquires the information of the ground gateway.

The information of the ground gateway may include a name, an identifier, or the like of the ground gateway.

S1801, the access network device sends a connection establishment request to the first core network device.

Accordingly, the first core network device receives a connection establishment request from the access network device.

The connection request is used for requesting to establish communication connection between the access network device and the first core network device, and the connection establishment request comprises information of the ground gateway. For example, the connection establishment request includes information of one or more terrestrial gateways to which the first core network device is connected.

S1802, the first core network device sends a connection establishment response to the access network device.

Accordingly, the access network device receives a connection setup response from the first core network device.

In this embodiment of the present application, the first core network device may refer to an access and mobility management function (AMF). The identifier of the first core network device may be a name of the first AMF, or a number of the first AMF, etc., such as the AMF 1.

Optionally, after the first core network device establishes the communication connection between the access network device and the first core network device, the first core network device sends a connection establishment response to the access network device. Or, for example, after receiving the connection establishment request from the access network device, the first core network device sends a connection establishment response to the access network device, and then establishes a communication connection between the access network device and the first core network device.

Thus, the establishment of the communication connection between the first core network device and the access network device is completed through the interaction between the first core network device and the access network device.

There are various specific implementation manners of the step of "S1800, the access network device acquiring the information of the terrestrial gateway" as follows. The following examples are given.

As a first possible implementation manner, referring to fig. 19, a specific implementation process of the access network device acquiring information of the terrestrial gateway may include the following steps:

s191, the access network device determines the information of the current service gateway according to the first corresponding relation.

Wherein the first corresponding relation comprises a corresponding relation between the information of the service gateway and the information of the time period, and is used for indicating that: and the service gateway connected with the access network equipment at different time periods.

For example, the first core network device connects two terrestrial gateways, and the identities of the two terrestrial gateways may be: GW1 and GW2 may use "1-GW 1" to represent the corresponding relationship between the first core network device and gateway GW1, and may use "1-GW 2" to represent the corresponding relationship between the first core network device and gateway GW2, where "1-" may represent the first core network device.

Illustratively, the ephemeris includes a correspondence between information of the serving gateway and information of the time period, and the access network device acquires information of two terrestrial gateways, GW1 and GW2, from the ephemeris based on current time information.

Therefore, the access network equipment acquires the information of the current service gateway through the first corresponding relation and provides information support for establishing communication connection with the first core network equipment.

As a second possible implementation manner, referring to fig. 20, a specific implementation process of the access network device acquiring the information of the terrestrial gateway may include the following steps:

s201, the access network equipment acquires information of the ground gateway from the detected ground gateway synchronous signal.

For example, if the access network device can detect a signal of a certain terrestrial gateway, the access network device obtains information of the terrestrial gateway from the detected terrestrial gateway synchronization signal, which may be denoted as GW 1.

In this way, the access network device obtains information of the ground gateways by detecting the synchronization signals of the ground gateways, so as to establish a communication connection with the first core network device through the ground gateways.

There are various specific implementation manners of the step of sending, by the access network device, the connection establishment request to the first core network device at S1801. The following examples are given.

As a first possible implementation manner, the connection establishment request includes information of the terrestrial gateway to which the first core network device is connected, so that the first core network device knows information of all terrestrial gateways during the communication connection with the access network device. At this time, the number of the terrestrial gateways included in the connection establishment request is equal to the number of the terrestrial gateways connected to the first core network device.

For example, referring to fig. 2, the ground gateway GW1 and the ground gateway GW2 are both connected to the first core network device, and in this case, the information of the ground gateway in the connection establishment request may include: 1-GW1 and 1-GW 2. Here, "1-" denotes a first core network device, "1-GW 1" denotes a ground gateway GW1 connected to the first core network device, and "1-GW 2" denotes a ground gateway GW2 connected to the first core network device.

As a second possible implementation manner, the connection establishment request includes information of the terrestrial gateway, which is acquired by the access network device based on the terrestrial gateway synchronization signal, so as to establish a communication connection with the first core network device through the terrestrial gateway.

Illustratively, at a certain time, the access network device obtains information of a certain ground gateway, denoted as GW1, from the synchronization signal of the ground gateway. At this time, the connection establishment request sent by the access network device may include: GW 1.

For example, in a first and a second possible implementation manners of the connection establishment request, the connection establishment request includes a TAC, and the TAC includes information of a terrestrial gateway. Table 2 shows the contents of the fields included in the connection establishment request:

TABLE 2

Information element/Group Name (IE/Group Name)
	>Supported TA items (Supported TA Item)
>>Tracking Area Code (TAC)
	>>Default Paging discontinuous reception (Default Paging DRX)

As a third possible implementation manner, the connection establishment request includes information of the serving gateway and time information, the time information includes information of a time period, and the serving gateways to which the access network device connects at different time periods are different.

Illustratively, the connection establishment request may include: GW1, start time: 12:00, duration: 40 min; GW2, start time: 12:41, duration: and 20 min. Where, "GW 1, start time: 12:00, duration: 40min "indicates that from the time 12:00, there is a communication connection between the access network device and the first core network device through the serving gateway GW1 for a duration of 40 minutes, and the information of the tracking area includes information of the serving gateway GW 1. "GW 2, start time: 12:41, duration: 20min "indicates that starting at the time 12:41, there is a communication connection between the access network device and the first core network device through the serving gateway GW2 for a duration of 20 minutes, and the information of the tracking area includes information of the serving gateway GW 2.

As a fourth possible implementation, the connection establishment request includes information of the serving gateway and time information, the time information includes information of the sub-period, and one or more sub-periods constitute a time period. Different sub-periods correspond to different sub-regions, a certain sub-region belongs to the coverage area of a certain service gateway, and the service gateway is a gateway corresponding to the time period formed by the sub-periods.

Illustratively, the connection establishment request may include: GW1-1, start time: 10:00, duration: 30 min; GW1-2, start time: 10:31, duration: and (3) 30 min. Where "GW 1" represents a gateway, "-1" represents sub-region 1, "-GW 1-1" represents sub-region 1 of gateway GW1, "-2" represents sub-region 2, "GW 1-2" represents sub-region 2 of gateway GW 1. "GW 1-1, start time: 10:00, duration: 30min "indicates that from the time of 10:00, the access network device broadcasts a message to sub-area 1 of the serving gateway through the communication connection between the serving gateway GW1 and the first core network device for a duration of 30 minutes, and the information of the tracking area includes information of the serving gateway GW1 and information of the sub-area 1. "GW 1-2, start time: 10:31, duration: 30min "indicates that from the time 10:31, the access network device broadcasts a message to sub-area 2 of the serving gateway through the communication connection between the serving gateway GW1 and the first core network device for a duration of 30 minutes, and the information of the tracking area includes information of the serving gateway GW1 and information of the sub-area 2.

Illustratively, the connection establishment request includes information of the serving gateway and time information. Table 3 shows the contents of the fields included in the connection establishment request:

TABLE 3

Information element/Group Name (IE/Group Name)
	>Supported TA items (Supported TA Item)
>>Tracking Area Code (TAC)
	>>Start time (StartTime)
>>>Time (hour)
	>>>Fen (minute)
>>>Second (second)
	>>Duration (Duration)
>>Default Paging discontinuous reception (Default Paging DRX)

In addition, for the implementation (the second possible implementation manner of S1801) that "the access network device acquires information of the terrestrial gateway from the synchronization signal of the terrestrial gateway", the access network device determines the serving gateway based on the signal strength of each terrestrial gateway. If the serving gateway changes, the information of the tracking area determined based on the serving gateway also changes accordingly. The connection establishment request sent by the access network device only includes information of the ground gateway acquired from the synchronization signal of the ground gateway, and the first core network device needs to acquire information of a tracking area updated each time by the access network device, so as to update the corresponding relationship between the access network device and the service gateway in real time, and record the corresponding relationship as the second corresponding relationship. Next, a process after the access network device updates the information of the tracking area is explained:

referring to fig. 20, in a scenario, a serving gateway of an access network device switches between gateways connected to the same core network device (e.g., a first core network device), at this time, after the access network device updates information of a tracking area, it needs to send a TA update request to the first core network device, and a specific implementation process may include the following steps:

s202, the access network equipment sends a TA updating request to the first core network equipment.

Correspondingly, the first core network device obtains the TA update request from the access network device.

The TA updating request comprises updated information of the tracking area, the updated information of the tracking area comprises information of a service gateway, the service gateway comprises a gateway determined from ground gateways connected with the access network equipment, and the TA updating request is used for requesting to update the corresponding relation between the information of the service gateway and the access network equipment.

Illustratively, the serving gateway of the access network device changes: the ground gateway GW1 connected by the first core network device is switched to the ground gateway GW 2. At this time, the TA update request may include information of the terrestrial gateway GW2 of the first core network device, such as 1-GW 2. Here, "1-" indicates a first core network device, and "GW 2" indicates information of a ground gateway.

S203, the first core network device sends a TA update response to the access network device.

Accordingly, the access network device receives a TA update response from the first core network device.

It should be noted that, the first core network device may first update the second corresponding relationship between the serving gateway and the access network device in the TA update request, and then send a TA update response to the access network device. Or, the first core network device may send a TA update response to the access network device first, and then update the corresponding relationship between the serving gateway and the access network device in the TA update request. The embodiment of the present application does not limit the execution sequence for updating the second corresponding relationship by the first core network device and sending the TA update response to the access network device.

Referring to fig. 20, in another scenario, a serving gateway of an access network device switches between terrestrial gateways connected to different core network devices, e.g., the serving gateway switches from a terrestrial gateway connected to a first core network device to a terrestrial gateway connected to a second core network device. At this time, after the access network device updates the information of the tracking area, it needs to send a TA update request to the second core network device, and the specific implementation process may include the following steps:

s204, the access network equipment sends a TA updating request to the second core network equipment.

Correspondingly, the second core network device obtains the TA update request from the access network device.

Illustratively, the serving gateway of the access network device changes: the terrestrial gateway GW2 connected by the first core network device is switched to the terrestrial gateway GW1 connected by the second core network device. At this time, the TA update request may include information of the terrestrial gateway GW1 of the second core network device, such as 2-GW 1. Here, "2-" indicates the second core network device, and "GW 1" indicates information of the ground gateway.

S205, the second core network device sends a TA update response to the access network device.

Accordingly, the access network device receives a TA update response from the second core network device.

And similarly. In the embodiment of the present application, there is no limitation on the execution sequence in which the second core network device updates the second correspondence (the correspondence between the serving gateway and the access network device) and sends the TA update response to the access network device.

Exemplarily, the TA update request includes a TAC, and the TAC includes updated information of the serving gateway. The contents of the fields added by the TA update request can be seen in table 4.

Table 4 shows the field contents included in the TA update request:

TABLE 4

Information element/Group Name (IE/Group Name)
	>Supported TA items (Supported TA Item)
>>Tracking Area Code (TAC)

Therefore, through the processing, the access network equipment reports the updated service gateway to the core network equipment, so that the core network equipment updates the corresponding relationship between the service gateway and the access network equipment in real time and provides an information basis for the paging process.

Next, the communication method according to the embodiment of the present application will be described in detail with information of the serving gateway as information of the tracking area.

As a first possible implementation manner, referring to fig. 21, a specific implementation process is as follows:

s2100, the access network device obtains an ID of the ground gateway GW 1.

Illustratively, the access network device obtains the ID of the terrestrial gateway GW1 from a synchronization signal of the terrestrial gateway GW1, or obtains the ID of the terrestrial gateway GW1 through configuration information, such as an ephemeris.

S2101, the access network equipment sends a connection establishment request to the first core network equipment.

The first core network device is a core network device to which a ground gateway GW1 is connected, the connection request is used to request establishment of a communication connection between the access network device and the first core network device, and the connection establishment request includes an ID (GW1-ID) of a ground gateway GW 1. When the access network device can acquire information of only one ground gateway GW1, the ground gateway GW1 is used as a serving gateway.

For example, the first core network device may be an access and mobility management function (AMF), and the access network device fills the acquired information of the terrestrial gateway into the TAC and reports the connection establishment request to the AMF through the interface. Wherein the connection setup request comprises the TAC.

S2102, the first core network device sends a connection setup response to the access network device.

The connection establishment response may carry the number of the AMF, for example, the connection establishment response carries the AMF 1. Alternatively, the connection setup response may also carry the name of the AMF.

S2103, the first core network device stores a corresponding relationship between the first service gateway and the access network device.

Illustratively, the first core network device establishes and stores a correspondence between the serving gateway GW1 and the access network device, which is denoted as a second correspondence.

S2104, the access network device sends the broadcast message.

Wherein, the broadcast message includes the information of the service gateway. For example, the broadcast message includes a TAC including information of the service gateway. Referring to fig. 21, the access network device accesses the first core network device through GW1, i.e. the current serving gateway is GW1, and thus, the broadcast message may include GW1-ID, for example. The terminal at this time is a terminal located in the service area of the ground gateway GW 1.

Illustratively, the broadcast message sent by the first core network device includes a System Information Block (SIB), and the SIB carries information GW1-ID of the serving gateway.

Optionally, when the access network device detects signals of other ground gateways, it may determine whether to perform service gateway switching based on the ground gateway signals and the signal quality of the current service gateway (i.e., the first service gateway), and specifically, the communication method according to the embodiment of the present application may further include the following steps S2105 to S2107:

(optional) S2105, the access network device obtains the ID of the terrestrial gateway GW 2.

(optional) S2106, the access network device sends a connection establishment request to the second core network device.

The second core network device is a core network device to which the ground gateway GW2 is connected, the connection request is used to request establishment of a communication connection between the access network device and the second core network device, and the connection establishment request includes an ID (GW2-ID) of the ground gateway GW 2.

(optional) S2107, the second core network device sends a connection establishment response to the access network device.

Illustratively, the connection establishment response includes AMF 2.

Optionally, when the access network device determines that the signal quality of the ground gateway GW2 meets the handover condition of the serving gateway, then S2108 to S2112 are executed:

(optional) S2108, the access network device sends a handover request to the second core network device.

Wherein the handover request is for requesting handover of the serving gateway from the first serving gateway (GW1) to the second serving gateway (GW2), the handover request including an identification of the second serving gateway (GW 2-ID). Optionally, the handover request includes an identification of the access network device (gNB-ID).

(optional) S2109, the second core network device sends a handover request to the first core network device.

Wherein the handover request is for requesting a handover of a serving gateway of the access network device from a first serving gateway (GW1) to a second serving gateway (GW 2).

(optional) S2110, the first core network device sends a handover confirm message to the second core network device.

Correspondingly, the second core network device receives the handover confirmation message from the first core network device.

S2111, the second core network equipment updates the corresponding relation between the service gateway and the access network equipment.

Illustratively, the serving gateway GW2 is substituted for the serving gateway GW1, and a second correspondence between the serving gateway GW2 and the access network device is established and stored.

S2112, the second core network device sends a handover response to the access network device.

As a possible implementation, the handover response includes information of the second serving gateway, such as the GW 2-ID.

In the embodiment of the present application, the execution of S2111 is not limited actually. The second core network device may execute S2111 after receiving the handover request (i.e., S2108), may execute S2111 after S2109, S2110, or S2112, or execute S2111 at other time.

S2113, the access network equipment sends the broadcast message.

The broadcast message includes information of the serving gateway, namely GW 2-ID. The terminal at this time is a terminal in the service area of the serving gateway GW 2.

It will be appreciated that the updated serving gateway information may be broadcast after the access network device receives the updated serving gateway information. Therefore, the terminal can analyze the broadcast message through a Broadcast Control Channel (BCCH), and then accurately acquire tracking area information, thereby improving the accuracy of the TAU.

As a second possible implementation manner, the access network device can obtain information of the ground gateway from the ephemeris, and then connect the location of the terminal. Referring to fig. 22, the specific implementation process is as follows:

s2200, the access network equipment acquires the information of the ground gateway from the ephemeris.

Illustratively, the access network device reads from the ephemeris information all the terrestrial gateways (e.g., terrestrial gateway GW1 and terrestrial gateway GW2) that are to be connected from the AMF.

S2201, the access network device sends a connection establishment request to the first core network device.

The first core network device is a core network device to which the ground gateway GW1 and the GW2 are connected, the connection request is used to request to establish a communication connection between the access network device and the first core network device, and the connection establishment request includes IDs (such as 1-GW1-ID and 1-GW2-ID) of the ground gateway GW1 and the GW 2.

Illustratively, the first core network device may be an AMF. The ground gateway obtained by the access network equipment from the ephemeris is used as a service gateway during connection with the AMF. The access network device fills the information of all the ground gateways (such as the ground gateway GW1 and the ground gateway GW2) into the TAC, and reports the information to the AMF from the interface to inform all the TAC information during the connection with the AMF.

S2202, the first core network device sends a connection establishment response to the access network device.

S2203, the first core network device stores a corresponding relationship between the service gateway and the access network device.

Illustratively, the first core network device stores a correspondence between the service gateways (1-GW1 and 1-GW2) and the access network devices, respectively, and is denoted as a second correspondence.

S2204, the access network equipment determines a service gateway.

For example, the access network device determines that the signal strength of the connected terrestrial gateway GW1 is greater than the signal strength of the connected terrestrial gateway GW2, and selects the terrestrial gateway GW1 as the serving gateway.

S2205, the access network equipment sends the broadcast message.

Wherein, the broadcast message includes the information of the service gateway. The current serving gateway is the terrestrial gateway GW1 of the first core network device, and thus the broadcast message may include, for example, the 1-GW 1-ID.

S2206, the access network equipment determines a service gateway.

For example, the access network device determines that the signal strength of the connected terrestrial gateway GW2 is greater than the signal strength of the connected terrestrial gateway GW1, and selects the terrestrial gateway GW2 as the serving gateway.

S2207, the access network equipment sends the broadcast message.

Wherein, the broadcast message includes the information of the current service gateway. The current serving gateway is the terrestrial gateway GW2 of the first core network device, and thus the broadcast message may include, for example, the 1-GW 2-ID.

It should be noted that, when the access network device moves in the air, the access network device may be in coverage areas of different core network devices at different time periods, and in order to ensure that the access network device establishes a connection with a corresponding core network device, information of a ground gateway of the corresponding core network device needs to be acquired. Optionally, the access network device obtains information of another core network device, for example, a ground gateway to which the second core network device is connected, based on the ephemeris, for example, the 2-GW 1. Here, "2-" denotes a second core network device, and "GW 1" denotes a ground gateway to which the second core network device is connected.

After obtaining the information of the terrestrial gateway of the second core network device, optionally, the access network device may establish connection with the core network device based on the information of the terrestrial gateway, that is, the communication method according to the embodiment of the present application may further include the following steps S2208 to S2210:

(optional) S2208, the access network device sends a connection establishment request to the second core network device.

The second core network device is a core network device to which the terrestrial gateway GW2 is connected, the connection request is used to request to establish a communication connection between the access network device and the second core network device, and the connection establishment request includes an ID (such as 2-GW1-ID) of the terrestrial gateway GW 1.

Illustratively, the second core network device may be an AMF. The ground gateway obtained by the access network equipment from the ephemeris is used as a service gateway during connection with the AMF. The access network equipment fills the information of all the ground gateways (such as the ground gateway GW1) into the TAC and reports the information to the AMF from the interface so as to inform all the TAC information during the connection with the AMF.

(optional) S2209, the second core network device sends a connection establishment response to the access network device.

The connection setup response may carry the number of the AMF, for example, the connection setup response carries AMF 2. Alternatively, the connection setup response may also carry the name of the AMF.

(optional) S2210, the second core network device stores a correspondence between the serving gateway and the access network device.

Illustratively, the second core network device stores a second correspondence between the serving gateway (2-GW1) and the access network device.

(optional) S2211, the access network device determines a serving gateway.

For example, the access network device determines that the signal strength of the terrestrial gateway (2-GW1) of the connected second core network device is greater than the signal strength of the serving gateway (1-GW2), and selects the terrestrial gateway (2-GW1) of the second core network device as the serving gateway.

(optional) S2212, the access network device sends the broadcast message.

Wherein, the broadcast message includes the information of the service gateway. The current serving gateway is the terrestrial gateway GW1 of the second core network device, and thus the broadcast message may include, for example, the 2-GW 1-ID.

S2213, the access network device sends a disconnection request to the first core network device.

Accordingly, the first core network device receives a disconnection request from the access network device.

The release request is used for requesting to disconnect the communication connection between the access network device and the first core network device.

S2214, the first core network device sends a disconnection response to the access network device.

Optionally, the first core network device may send the disconnection response to the access network device first, and then disconnect the communication connection with the access network device, or may disconnect the communication connection with the access network device first, and then send the disconnection response to the access network device.

In fig. 22, in a short period of time, the access network device may be in the coverage of a certain terrestrial gateway (e.g., 1-GW1), the access network device is connected to the gateway 1-GW1, and performs information interaction with the first core network device through the gateway 1-GW1, in this case, the gateway 1-GW1 is the only gateway connected to the access network device, and the gateway 1-GW1 is the serving gateway of the access network device, in this case, the communication method in this embodiment of the present application includes S2200-S2205, S2213, and S2214. For a longer period of time, the access network device may cross a terrestrial gateway, i.e., be within the coverage of a different terrestrial gateway, such as the gateway 1-GW1, and then be within the coverage of the gateway 1-GW2, at which time the gateway 1-GW2 is the serving gateway for the access network device and interacts with the first core network device through the gateway 1-GW2 based on the serving gateway determination step. In this case, the communication method of the embodiment of the present application includes S2200 to S2207, S2213, and S2214. For a longer period of time, the access network device may still cross the terrestrial gateway, for example, before being in the coverage of the gateway 1-GW2, and then the access network device is in the coverage of the gateway 2-GW1, at which time, based on the serving gateway determination step, the gateway 2-GW1 is the serving gateway of the access network device and performs information interaction with the second core network device through the gateway 2-GW 1. In this case, the communication method of the embodiment of the present application includes S2200 to S2214. That is, the access network device is first connected to the first core network device and uses the terrestrial gateway of the first core network device as the serving gateway, and then, due to the change in the position of the access network device in the air, the access network device is connected to the second core network device and uses the terrestrial gateway of the second core network device as the serving gateway.

As a third possible implementation manner, the access network device can acquire information of the ground gateway from a synchronization signal of the ground gateway, so as to manage the location of the terminal. Referring to fig. 23, the specific implementation process is as follows:

and S2300, the access network equipment acquires the information of the ground gateway from the detected ground gateway synchronous signal.

Illustratively, the synchronization signal of the terrestrial gateway detected by the access network device acquires information of the terrestrial gateway, GW 1. The access network device can acquire information of only one terrestrial gateway, GW1, and in this case, takes the terrestrial gateway GW1 as a serving gateway.

S2301, the access network device sends a connection establishment request to the first core network device.

The first core network device is a core network device to which the terrestrial gateway GW1 is connected, the connection request is used to request to establish a communication connection between the access network device and the first core network device, and the connection establishment request includes an ID of the terrestrial gateway GW1, such as 1-GW 1-ID. Where "1-" denotes a first core network device, "GW 1" denotes a terrestrial gateway, and 1-GW1-ID denotes a terrestrial gateway GW1 connected to the first core network device.

Illustratively, the first core network device may be an AMF. And the access network equipment acquires the information of the ground gateway from the synchronization signal. The access network device fills the information of the ground gateway (such as the ground gateway GW1) in the TAC, and reports the information to the AMF through the interface.

S2302, the first core network device sends a connection establishment response to the access network device.

S2303, the first core network device stores a correspondence between the service gateway and the access network device.

Illustratively, the first core network device stores a correspondence between the serving gateway (1-GW1) and the access network device, denoted as a second correspondence.

S2304, the access network equipment determines a service gateway.

For example, if the access network device determines that the number of connected terrestrial gateways is one, the terrestrial gateway GW1 is used as the serving gateway.

S2305, the access network equipment sends the broadcast message.

Optionally, as the access network device moves, the access network device detects a signal of a terrestrial gateway GW2, such as 1-GW2, to which the first core network device is connected. Where "1-" denotes a first core network device and "GW 2" denotes a ground gateway.

(optional) S2306, the access network device determines a serving gateway.

(optional) S2307, the access network device sends the broadcast message.

Wherein, the broadcast message includes the information of the service gateway. The current serving gateway is the terrestrial gateway GW2 of the first core network device, and thus the broadcast message may include, for example, the 1-GW 2-ID.

(optional) S2308, the access network device sends a TA update request to the first core network device.

The TA update request comprises information of a tracking area, the information of the tracking area comprises information of a service gateway (1-GW2-ID), and the TA update request is used for requesting to update a second corresponding relation between the information of the service gateway (1-GW2-ID) and the access network equipment.

(optional) S2309, the first core network device sends a TA update response to the access network device.

Optionally, as the access network device moves, the access network device detects a signal of a terrestrial gateway GW1, such as 2-GW1, to which the second core network device is connected. Here, "2-" denotes a second core network device, and "GW 1" denotes a ground gateway.

(optional) S2310, the first core network device updates a corresponding relationship between the service gateway and the access network device.

Illustratively, the first core network device stores a second correspondence between the serving gateway (1-GW2) and the access network device.

(optional) S2311, the access network device sends a connection establishment request to the second core network device.

The second core network device is a core network device to which the terrestrial gateway GW1 is connected, the connection request is used to request to establish a communication connection between the access network device and the second core network device, and the connection establishment request includes an ID (such as 2-GW1-ID) of the terrestrial gateway GW 1.

(optional) S2312, the second core network device sends a connection establishment response to the access network device.

Illustratively, the connection establishment response includes AMF 2.

(optional) S2313, the second core network device stores a correspondence between the service gateway and the access network device.

Illustratively, the second core network device stores a second correspondence between the terrestrial gateway (2-GW1) and the access network device.

(optional) S2314, the access network device determines a serving gateway.

For example, the access network device determines that the signal strength of the ground gateway GW1 of the connected second core network device is greater than the signal strength of the serving gateway GW2, and selects the ground gateway GW1 of the second core network device as the serving gateway.

(optional) S2315, the access network device sends the broadcast message.

(optional) S2316, the access network device sends a TA update request to the second core network device.

The TA update request comprises information of a tracking area, the information of the tracking area comprises information of a service gateway (2-GW1-ID), and the TA update request is used for requesting to update a second corresponding relation between the information of the service gateway (2-GW1-ID) and the access network equipment.

(optional) S2317, the second core network device sends a TA update response to the access network device.

In fig. 23, in a short period of time, the access network device may be in the coverage of a certain terrestrial gateway (e.g., 1-GW1), the access network device is connected to the gateway 1-GW1, and performs information interaction with the first core network device through the gateway 1-GW1, in this case, the gateway 1-GW1 is the only gateway connected to the access network device, and then the gateway 1-GW1 is the serving gateway of the access network device, in this case, the communication method in this embodiment includes S2300-S2305. For a longer period of time, the access network device may cross the terrestrial gateway, i.e. be in the coverage of a different terrestrial gateway, for example, previously in the coverage of the gateway 1-GW1, and then the access network device is in the coverage of the gateway 1-GW2, at which time, based on the serving gateway determination step, the gateway 1-GW2 is the serving gateway of the access network device and performs information interaction with the first core network device through the gateway 1-GW 2. In this case, the communication method of the embodiment of the present application includes S2300 to S2310. For a longer period of time, the access network device may still cross the terrestrial gateway, for example, before being in the coverage of the gateway 1-GW2, and then the access network device is in the coverage of the gateway 2-GW1, at which time, based on the serving gateway determination step, the gateway 2-GW1 is the serving gateway of the access network device and performs information interaction with the second core network device through the gateway 2-GW 1. In this case, the communication method of the embodiment of the present application includes S2300 to S2317. That is, the access network device is first connected to the first core network device and uses the terrestrial gateway of the first core network device as the serving gateway, and then, due to the change in the position of the access network device in the air, the access network device is connected to the second core network device and uses the terrestrial gateway of the second core network device as the serving gateway.

Next, the information of the tracking area is determined comprehensively by using the information of the serving gateway and the information of the sub-area (a partial area of the ground gateway coverage area), and the communication method of the present application is described in detail.

As a first possible implementation manner, referring to fig. 24, the specific implementation process is as follows:

s2400, the access network device obtains information of the sub-area of the serving gateway GW1 and a time period corresponding to the sub-area.

Illustratively, the access network device divides a time period corresponding to the current serving gateway by using configuration information, such as an ephemeris, and different sub-periods correspond to different sub-areas.

S2401, the access network device sends a connection establishment request to the first core network device.

For example: the first core network device is a core network device corresponding to a serving gateway GW1, a GW1-1-ID represents an identifier corresponding to a sub-region one of a serving gateway GW1 coverage area, and a GW1-2-ID represents an identifier corresponding to a sub-region two of a serving gateway GW1 coverage area. At this time, the connection establishment request may specifically include: GW1-1-ID, 30 min; GW1-2-ID, 30 min.

For example, the first core network device may be an access and mobility management function (AMF), and the access network device fills the TAC with information of the sub-area obtained by the serving gateway, and reports the connection establishment request to the AMF through the interface. Wherein the connection setup request comprises the TAC.

S2402, the first core network device sends a connection establishment response to the access network device.

Illustratively, the connection establishment response includes AMF 2.

S2403, the first core network device stores the information of the service gateway, the information of the sub-regions, the corresponding relation between the time periods corresponding to the sub-regions and the access network device, and records the corresponding relation as a fourth corresponding relation.

Illustratively, the first core network device establishes and stores "GW 1-1-ID, 30 min; GW1-2-ID, 30min "and access network equipment.

S2404, the access network equipment sends the broadcast message.

The broadcast message includes information of the serving gateway and information of the sub-area.

Illustratively, in the time period of 10: 00-10: 30, SIB1 is adopted to carry information GW1-1-ID of a serving gateway, and a broadcast message carrying GW1-1-ID is sent. In the time period of 10: 30-11: 00, SIB1 is adopted to carry information GW1-2-ID of a service gateway, and a broadcast message carrying GW1-2-ID is sent.

Optionally, when a new terrestrial gateway exists in the coverage area of the access network device, such as the terrestrial gateway GW2, and a communication connection is established between the access network device and the new terrestrial gateway, performing S2405 to S2407:

(optional) S2405, the access network device obtains information of the sub-region of the serving gateway GW2 and a time period corresponding to the sub-region.

(optional) S2406, the access network device sends a connection establishment request to the second core network device.

For example: the second core network device is a core network device connected to the serving gateway GW2, the GW2-1-ID represents an identifier corresponding to the sub-region one of the serving gateway GW2 coverage area, and the GW2-2-ID represents an identifier corresponding to the sub-region two of the serving gateway GW2 coverage area. At this time, the connection establishment request may specifically include: GW2-1-ID, 20 min; GW2-2-ID, 20 min.

(optional) S2407, the second core network device sends a connection establishment response to the access network device.

Wherein the connection establishment response includes AMF 2.

Optionally, when the access network device determines that the signal quality of the new serving gateway GW2 meets the handover condition of the serving gateway, then S2408 to S2412 are executed:

(optional) S2408, the access network device sends a handover request to the second core network device.

(optional) S2409, the second core network device sends a handover request to the first core network device.

(optional) S2410, the first core network device sends a handover confirmation message to the second core network device.

(optional) S2411, the second core network device stores the information of the serving gateway, the information of the sub-region, the time period corresponding to the sub-region, and the correspondence between the access network devices.

Illustratively, the second core network device establishes and stores "GW 2-1-ID, 20 min; GW2-2-ID, 20min ", and access network device.

(optional) S2412, the second core network device sends a handover response to the access network device.

In the embodiment of the present application, the execution of S2411 is not limited actually. The second core network device may perform S2411 after receiving the handover request (i.e., S2408), may perform S2411 after S2409, S2410, or S2412, or perform S2411 at other occasions.

(optional) S2413, the access network device sends the broadcast message.

The broadcast message also includes information of sub-areas, namely GW2-1-ID and GW 2-2-ID.

It will be appreciated that, after the access network device receives the updated serving gateway information, the tracking area information may be broadcast based on the updated serving gateway information. For example, in the time period of 11: 00-11: 20, a broadcast message carrying GW2-1-ID is sent. And sending the broadcast message carrying the GW2-2-ID in the time period of 11: 20-11: 40. Therefore, the terminal can analyze the broadcast message through a Broadcast Control Channel (BCCH), and then accurately acquire tracking area information, thereby improving the accuracy of the TAU.

In fig. 24, in a short period of time, the access network device may be located in a coverage area of a certain terrestrial gateway (e.g., GW1), and the access network device is connected to the gateway GW1 and performs information interaction with the first core network device through the gateway GW1, where the gateway GW1 is the only gateway connected to the access network device, and the gateway GW1 is the serving gateway of the access network device, in this case, the communication method in this embodiment of the present application includes S2400-S2404. For a longer period of time, the access network device may cross the terrestrial gateway, i.e. be in the coverage of a different terrestrial gateway, e.g. previously in the coverage of gateway GW1, and then the access network device is in the coverage of gateway GW2, at which time, based on the serving gateway determination step, gateway GW2 is the serving gateway of the access network device and performs information interaction with the second core network device through the gateway GW 2. In this case, the communication method according to the embodiment of the present application includes S2400 to S2413. That is, the access network device is first connected to the first core network device and uses the terrestrial gateway of the first core network device as the serving gateway, and then, due to the change in the position of the access network device in the air, the access network device is connected to the second core network device and uses the terrestrial gateway of the second core network device as the serving gateway.

As a second possible implementation manner, referring to fig. 25, the specific implementation process is as follows:

and S2500, the access network equipment acquires the information of the service gateway, the information of the sub-area and the information of the time period.

Illustratively, the access network device obtains each sub-area of the coverage area of the serving gateway GW1 and a corresponding time period of each sub-area through configuration information, such as an ephemeris.

S2501, the access network device sends a connection establishment request to the first core network device.

For example: the first core network device is a core network device connected to a serving gateway GW1, GW1-1-ID represents an identifier corresponding to a first sub-region of a serving gateway GW1 coverage area, and GW1-2-ID represents an identifier corresponding to a second sub-region of a serving gateway GW1 coverage area. At this time, the connection establishment request may specifically include: GW1-1-ID, start time: 10:00, duration: 30 min; GW1-2-ID, start time: 10:30, duration: and (5) 30 min.

S2502, the first core network device sends a connection establishment response to the access network device.

Illustratively, the connection establishment response includes AMF 1.

S2503, the first core network device stores a correspondence between the information of the serving gateway, the information of the sub-area, the information of the time period, the information of the sub-time period, and the access network device, and records the correspondence as a fourth correspondence.

Each time period corresponds to one service gateway, one or more sub-time periods form one time period, and each sub-time period corresponds to one sub-region and belongs to the coverage area of the service gateway corresponding to the formed time period.

Illustratively, the first core network device stores a "GW 1-1-ID, start time: 10:00, duration: 30 min; GW1-2-ID, start time: 10:30, duration: 30min "with a fourth correspondence to access network devices.

S2504, the access network equipment sends the broadcast message.

Optionally, as the access network device moves, a new terrestrial gateway, such as a terrestrial gateway GW2, exists in the coverage area of the access network device, and the second core network device is the core network device to which the terrestrial gateway GW2 is connected. Establishing communication connection between the access network device and the core network device to which the new ground gateway GW2 belongs, and executing the following steps:

(optional) S2505, the access network device sends a connection establishment request to the second core network device.

For example: the second core network device is a core network device connected with a ground gateway GW2, GW2-1-ID represents an identifier corresponding to a sub-region one of a ground gateway GW2 coverage area, and GW2-2-ID represents an identifier corresponding to a sub-region two of a ground gateway GW2 coverage area. At this time, the connection establishment request may specifically include: GW2-1-ID, start time: 11:00, duration: 20 min; GW2-2-ID, start time: 11:20, duration: and (5) 20 min.

For example, the second core network device may be an access and mobility management function (AMF), and the access network device fills the TAC with the information of the sub-area acquired by the serving gateway and reports the connection establishment request to the AMF through the interface. Wherein the connection setup request comprises the TAC.

(optional) S2506, the second core network device sends a connection setup response to the access network device.

Wherein the connection establishment response includes AMF 2.

(optional) S2507, the second core network device stores the information of the serving gateway, the information of the sub-area, the information of the time period, the information of the sub-time period, and the correspondence between the access network devices.

Illustratively, the second core network device stores "GW 2-1-ID, start time: 11:00, duration: 20 min; GW2-2-ID, start time: 11:20, duration: 20min "with a fourth correspondence to access network devices.

(optional) S2508, the access network device switches the information of the tracking area according to the time information.

(optional) S2509, the access network device sends the broadcast message.

Illustratively, in the time period of 11: 00-11: 20, SIB1 is adopted to carry information GW2-1-ID of a serving gateway, and a broadcast message carrying GW2-1-ID is sent. In the time period of 11: 20-11: 40, SIB1 is adopted to carry information GW2-2-ID of a service gateway, and a broadcast message carrying GW2-2-ID is sent.

Therefore, the terminal can analyze the broadcast message through a Broadcast Control Channel (BCCH), and then accurately acquire tracking area information, thereby improving the accuracy of the TAU.

In fig. 25, in a short period of time, an access network device may be in a coverage area of a certain terrestrial gateway (e.g., GW1), and the access network device is connected to the gateway GW1 and performs information interaction with a first core network device through the gateway GW1, where the gateway GW1 is the only gateway connected to the access network device, and the gateway GW1 is the serving gateway of the access network device, in this case, the communication method in this embodiment of the present application includes S2500-S2504. For a longer period of time, the access network device may cross the terrestrial gateway, i.e. be in the coverage of a different terrestrial gateway, e.g. previously in the coverage of gateway GW1, and then the access network device is in the coverage of gateway GW2, at which time, based on the serving gateway determination step, gateway GW2 is the serving gateway of the access network device and performs information interaction with the second core network device through the gateway GW 2. In this case, the communication method of the embodiment of the present application includes S2500 to S2509. That is, the access network device is first connected to the first core network device and uses the terrestrial gateway of the first core network device as the serving gateway, and then, due to the change in the position of the access network device in the air, the access network device is connected to the second core network device and uses the terrestrial gateway of the second core network device as the serving gateway.

The embodiment of the application also provides a communication method, which is applied to the process of paging the terminal. Referring to fig. 26, the communication method includes the steps of:

s2600, the first core network device determines an access network device connected to the serving gateway in the paging message sending time TA List.

S2601, the first core network device sends a paging message to the access network device.

Accordingly, the access network device receives a paging message from the first core network device.

The access network device includes an access network device connected to a serving gateway in a TA List, where the TA List includes information of a tracking area, and the information of the tracking area includes information of the serving gateway.

S2602, the access network equipment broadcasts the paging message.

Here, paging is performed based on an area covered by an access network device to which the gateway in the TA List is connected at a paging time (i.e., a time when the paging message is transmitted). Compared with the prior art, in which paging messages are sent in all cells indicated by the TA List, since information of a tracking area broadcasted by a satellite is always bound to a serving cell and the time of the satellite moves relative to the ground, and a terminal may frequently perform TAU even if the terminal does not move or moves at a low speed, the cell broadcasted by the satellite moves relative to the ground in the prior art, and the position of the terminal is indicated by the cell moving relative to the ground at the time in the prior art, which is poor in accuracy. And since the terminal may frequently perform TAU, the number of cells included in the TA List is huge. Thus, the paging message is sent to all cells of the TA List, the paging range is large, and a large paging resource is consumed. The information of the tracking area of the communication method provided by the embodiment of the application comprises the information of the service gateway, and the gateway is deployed on the ground, and the position of the gateway is fixed and unchanged, so that the terminal does not need to execute the TAU as long as the terminal does not exceed the coverage of the gateway even if the satellite moves relative to the ground at any moment and the terminal moves at a low speed. Because the frequency of executing TAU by the terminal is reduced in the embodiment of the application, the number of the service gateways included in the TA List of the terminal is small, the paging range is reduced, and the paging resource is saved.

It should be noted that, before sending the paging message to the access network device, the first core network device needs to determine the access network device to which the serving gateway in the paging message sending time TA List is connected. Next, a process of "the first core network device determines the access network device to which the serving gateway in the paging message transmission time TA List is connected" will be described:

as a first possible implementation manner, the information of the tracking area takes the serving gateway as a granularity, and the first core network device updates the second corresponding relationship, where the second corresponding relationship includes a dynamic corresponding relationship between the serving gateway and the access network device. Referring to fig. 27, at this time, the specific implementation process may include the following steps:

s271, the first core network device determines, according to the updated second correspondence, the access network device to which the serving gateway in the paging message sending time TA List is connected.

And the second corresponding relation comprises a corresponding relation between the service gateway and the access network equipment.

Illustratively, the information of the serving gateway included in the TA List includes: GW1, GW 2. The second correspondence updated in real time includes: GW1-gNB 1; GW2-gNB 2; GW3-gNB 3. Here, "GW 1-gNB 1" indicates that access network device gNB1 is served from a certain time (e.g., time t 1) to current gateway GW1, "GW 2-gNB 2" indicates that access network device gNB2 is served from a certain time (e.g., time t 1) to current gateway GW2, and "GW 3-gNB 3" indicates that access network device gNB3 is served from a certain time (e.g., time t 1) to current gateway GW 3. Based on the dynamic correspondence relationship between "GW 1 and gNB 1", the first core network device may determine that the access network device connected to the serving gateway GW1 in the TA List at the current time is gNB1, and based on the dynamic correspondence relationship between "GW 2 and gNB 2", the access network device connected to the serving gateway GW2 in the TA List at the current time is gNB 2. The current time is the time when the paging message pair needs to be sent.

Thus, based on the second correspondence (the correspondence between the serving gateway and the access network device) updated in real time, the first core network device may determine the access network device to which the serving gateway in the TA List is connected at the paging message sending time, so as to send the paging message through the access network device to which the serving gateway in the TA List is connected.

As a second possible implementation manner, the information of the tracking area still uses the serving gateway as a granularity, and the first core network device determines, based on a third correspondence, the access network device to which the serving gateway in the paging message sending time TA List is connected, where the third correspondence includes information of a time period and a correspondence between the access network device and the serving gateway. Referring to fig. 28, at this time, the specific implementation process may include the following steps:

s281, the first core network device determines, according to the third corresponding relationship, an access network device to which the serving gateway in the paging message sending time TA List is connected.

The third corresponding relationship includes information of a time period and a corresponding relationship between the access network device and the service gateway, and the third corresponding relationship is used to indicate: and the service gateway connected with the access network equipment at different time periods.

Illustratively, the information of the serving gateway in the TA List includes: GW1, GW 2.

The third correspondence in the ephemeris may include:

GW1-gNB1、10:00～10:30；GW1-gNB2、10:30～11:00；

GW2-gNB2、10:00～10:30；GW2-gNB3、10:30～11:00。

wherein, the GW1-gNB1 and 10: 00-10: 30 indicate that the gateway GW1 provides service for the access network device gNB1 in the time period of 10: 00-10: 30;

"GW 1-gNB2, 10: 30-11: 00" indicates that gateway GW1 is serving access network device gNB2 during the time period of "10: 30-11: 00";

"GW 2-gNB2, 10: 00-10: 30" indicates that the gateway GW2 is providing service for the access network device gNB2 during the time period of "10: 00-10: 30";

"GW 2-gNB3, 10: 30-11: 00" indicates that gateway GW2 is serving access network device gNB3 during the time period "10: 30-11: 00".

If the time of sending the paging message is 10:45, the first core network device may determine that the access network device connected with the GW1 in the time TA List of sending the paging message is the gsb 2 based on the corresponding relationship of "GW 1-gNB2, 10: 30-11: 00" in the ephemeris; based on the corresponding relationship of "GW 2-gNB3 and 10:30 ~ 11: 00" in the ephemeris, it can be determined that the access network device connected with GW2 in TA List is gNB 3.

As a third possible implementation manner, for the information of the tracking area with the sub-area of the serving gateway as the granularity, the information of the tracking area in the talk also includes the information of the sub-area. The connection establishment request received by the first core network device from the access network device includes information of the serving gateway and information of the sub-area, and the first core network device updates a fourth corresponding relationship among the serving gateway, the sub-area of the serving gateway, and the access network device in real time according to the received connection establishment request, so as to determine the access network device that needs to send the paging message in the process of paging the terminal, see fig. 29, where a specific implementation process may include the following steps:

and S291, the first core network device determines, according to the fourth correspondence, the access network device corresponding to the sub-area in the paging message sending time TA List.

The fourth corresponding relation comprises the corresponding relation between the information of the sub-period and the information of the access network equipment and the sub-region, one or more sub-periods form a time period, and the formed time period corresponds to one service gateway. Each sub-period corresponds to a sub-region, a certain sub-region belongs to the coverage area of a certain service gateway, and the service gateway is the service gateway corresponding to the time period formed by the sub-period. The fourth correspondence is to indicate: and accessing the sub-areas corresponding to the network equipment in different sub-periods.

Here, since the area information in the TA List includes: the first core network device determines the sending area of the paging message according to the sub-area information in the TA List, so that the paging range can be reduced, and the paging resource can be saved. For example, referring to fig. 30, in fig. 30, the right half of the broken-line elliptical region is sub-region 1 (denoted as "-1") and the left half of the broken-line elliptical region is sub-region 2 (denoted as "-2"). If the information of the tracking area broadcasted by the access network device includes GW1-ID, after the terminal performs TAU, the information of the tracking area in the TA List corresponding to the terminal includes: GW1-ID, then, when paging a terminal, the paging message is sent through gNB1 and gNB2 by indexing GW1-ID in TA List to gNB1 and gNB2 which are serving GW 1. If the information of the tracking area broadcasted by the gNB1 includes GW1-2-ID, after the terminal executes TAU, the information of the tracking area in the TA List corresponding to the terminal includes: GW1-2-ID, then, when paging a terminal, the paging message is sent through the gNB1 indexed to the gNB1 with GW1 as the serving gateway through the GW1-2-ID in the TA List. Therefore, only the gNB1 transmits the paging message, and the transmission range of the paging message is only the area covered by the gNB1, so that the paging range can be reduced, and the paging resource can be saved. Further, compared with the method that only the information (GW1-ID) of the serving gateway is used for terminal location connection and paging, the sub-area information in the TA List can more accurately represent the location of the terminal, and further save paging resources.

The above-mentioned scheme provided in the embodiment of the present application is introduced mainly from the perspective of interaction between different network elements. It is to be understood that the first terminal device and the second terminal device include hardware structures and/or software modules for performing the respective functions in order to realize the functions. The elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein may be embodied in hardware or in a combination of hardware and computer software. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present teachings.

In the embodiment of the present application, the communication apparatus may be divided into functional units according to the method example, for example, each functional unit may be divided corresponding to each function, or two or more functions may be integrated into one processing unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit. It should be noted that, in the embodiment of the present application, the division of the unit is schematic, and is only one logic function division, and when the actual implementation is realized, another division manner may be provided.

Fig. 31 shows a schematic block diagram of a communication apparatus provided in an embodiment of the present application. The communication means 3100 may be in the form of software, a device, or a component in a device (e.g., a system-on-a-chip). The communication device 3100 includes: a memory unit 3101, a processing unit 3102 and a communication unit 3103.

The communication unit 3103 may also be divided into a transmitting unit (not shown in fig. 31) and a receiving unit (not shown in fig. 31). The sending unit is configured to support the communication device 3100 to send information to other network elements. A receiving unit for supporting the communication device 3100 to receive information from other network elements.

A storage unit 3101 for storing program code and data of device 3100, which may include, but is not limited to, raw data or intermediate data, etc.

When the communication device is used as a terminal, a communication unit is used for receiving a broadcast message from the access network equipment, wherein the broadcast message comprises the information of a tracking area, and the information of the tracking area comprises the information of a service gateway; and the storage unit is used for storing the information of the tracking area.

In one possible design, the processing unit is configured to perform tracking area update TAU if the information of the tracking area in the broadcast message received by the communication unit is not in the tracking area List TA List of the storage unit.

In one possible design, the processing unit is configured to perform tracking area update TAU if the information of the tracking area with serving gateway granularity received by the communication unit is not in the tracking area List TA List of the storage unit.

When the communication device is used as access network equipment, the processing unit is used for acquiring information of a tracking area, wherein the information of the tracking area comprises information of a service gateway; a communication unit for transmitting a broadcast message including information of the tracking area.

and the first and second broadcasting devices are further configured to send a second broadcast message in a second time period, where the second broadcast message includes information of a serving gateway corresponding to the second time period, and the information of the serving gateway included in the first broadcast message is different from that included in the second broadcast message.

and the receiver is further configured to send a fourth broadcast message in a fourth time period, where the fourth broadcast message includes information of a sub-area corresponding to the fourth time period, and the information of the sub-area included in the third broadcast message is different from that included in the fourth broadcast message.

When the communication device is used as an access network device, the communication unit is configured to send a connection establishment request to the first core network device, where the connection establishment request is used to request establishment of a communication connection between the access network device and the first core network device, and the connection establishment request includes information of one or more terrestrial gateways corresponding to the first core network device; and is further configured to receive a connection setup response from the first core network device.

the communication unit is further configured to receive a TA update response from the first core network device.

In a possible design, the processing unit is configured to obtain and determine information of a current serving gateway according to the first corresponding relationship to obtain information of the tracking area. Wherein the first corresponding relationship comprises a corresponding relationship between information of the service gateway and information of the time period.

In one possible design, the connection establishment request further includes time information, where the time information includes information of a time period, and information of a serving gateway corresponding to the access network device at different time periods is different.

In one possible design, the connection establishment request further includes information of a sub-region, the time information further includes information of a sub-period, one time period includes one or more sub-periods, the sub-region belongs to a coverage area of a serving gateway of the time period, and different sub-periods correspond to different sub-regions.

When the communication device is used as a core network device, the communication unit is configured to receive a connection establishment request from an access network device, where the connection establishment request is used to request establishment of a communication connection between the access network device and a first core network device, and the connection establishment request includes information of one or more terrestrial gateways to which the first core network device is connected; and is further configured to send a connection setup response to the access network device.

When the communication device is used as an access network device, the communication unit is used for receiving the paging message from the first core network device and broadcasting the paging message. The access network device includes an access network device to which the serving gateway in the sending time tracking area List TA List is connected.

When the communication apparatus is used as a core network device, the processing unit is configured to determine an access network device to which a serving gateway in a paging message sending time tracking area List TA List is connected, and the communication unit is configured to send a paging message to the access network device. The tracking area List TA List includes information of tracking areas, and the information of tracking areas includes information of a service gateway.

In one possible design, a processing unit, configured to determine an access network device to which a serving gateway in a paging message transmission time tracking area List TA List is connected, includes: and the second mapping unit is configured to obtain the second mapping relationship, and determine, according to the second mapping relationship, the access network device to which the serving gateway in the paging message sending time TA List is connected. The second corresponding relation comprises a corresponding relation between the service gateway and the access network equipment.

In one possible design, a processing unit, configured to determine an access network device to which a serving gateway in a paging message transmission time tracking area List TA List is connected, includes: and the access network device is used for determining the access network device connected with the serving gateway in the paging message sending time TA List according to the third corresponding relation. The third corresponding relation comprises information of the time period and a corresponding relation between the access network equipment and the service gateway.

In one possible design, the information of the tracking area further includes information of a sub-area, and the processing unit is configured to determine an access network device to which a serving gateway in the tracking area List TA List is connected at a paging message sending time, and includes: and the access network device is used for determining the access network device corresponding to the sub-area in the paging message sending time TA List according to the fourth corresponding relation. The fourth corresponding relationship includes a corresponding relationship between information of the sub-period and information of the access network device and the sub-region, one or more sub-periods constitute a time period, the sub-region belongs to a coverage area of the serving gateway in the constituted time period, and the fourth corresponding relationship is used to indicate: and in different sub-periods, accessing the corresponding sub-regions of the network equipment.

Among other things, processing unit 3102 may be a processor or controller, which may be, for example, a CPU, general purpose processor, DSP, ASIC, FPGA or other programmable logic device, transistor logic device, hardware component, or any combination thereof. Which may implement or perform the various illustrative logical blocks, modules, and circuits described in connection with the disclosure. A processor may also be a combination of computing functions, e.g., comprising one or more microprocessors, a combination of a DSP and a microprocessor, and the like.

The communication unit 3103 may be a communication interface, a transceiver circuit, or the like, wherein the communication interface is referred to as a generic term, and in a specific implementation, the communication interface may include a plurality of interfaces, which may include, for example: terminals and interfaces between terminals and/or other interfaces.

The storage unit 3101 may be a memory.

When the processing unit 3102 is a processor, the communication unit 3103 is a communication interface, and the storage unit 3101 is a memory, the communication device 3200 according to the embodiment of the present application may be as shown in fig. 32.

Referring to fig. 32, the device 3200 includes: processor 3202, transceiver 3203, memory 3201.

The transceiver 3203 may be a separate transmitter for transmitting information to other devices, or a separate receiver for receiving information from other devices. The transceiver may also be a component that integrates information sending and receiving functions, and the embodiment of the present application does not limit the specific implementation of the transceiver.

Optionally, the device 3200 may also include a bus 3204. The transceiver 3203, the processor 3202, and the memory 3201 may be connected to each other through a bus 3204; the bus 3204 may be a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The bus 3204 may be divided into an address bus, a data bus, a control bus, and the like. For ease of illustration, only one thick line is shown in FIG. 32, but this is not intended to represent only one bus or type of bus.

Those of ordinary skill in the art will understand that: in the above embodiments, the implementation may be wholly or partially realized 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. The procedures or functions described in accordance with the embodiments of the application are all or partially generated when the computer program instructions are loaded and executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device including one or more available media integrated servers, data centers, and the like. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., Digital Video Disk (DVD)), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one type of logical functional division, and other divisions may be realized in practice, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection of some interfaces, devices or units, and may be an electric or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may also be distributed on multiple network devices (e.g., terminals). Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each functional unit may exist independently, or two or more units may be integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

Through the above description of the embodiments, those skilled in the art will clearly understand that the present application can be implemented by software plus necessary general hardware, and certainly, the present application can also be implemented by hardware, but in many cases, the former is a better implementation. Based on such understanding, the technical solutions of the present application may be substantially implemented or a part of the technical solutions contributing to the prior art may be embodied in the form of a software product, where the computer software product is stored in a readable storage medium, such as a floppy disk, a hard disk, or an optical disk of a computer, and includes several instructions for enabling a computer device (which may be a personal computer, a server, or a network device) to execute the methods described in the embodiments of the present application.

The above description is only an embodiment of the present application, but the scope of the present application is not limited thereto, and all changes and substitutions within the technical scope of the present application should be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of communication, comprising:

a terminal receives a broadcast message from access network equipment, and all or part of functional modules of the access network equipment are deployed in one of the following: in an empty platform, a satellite, or a communication device moving in high altitude, the broadcast message includes information of a tracking area, and the information of the tracking area includes information of a service gateway; the service gateway is a ground gateway;

the terminal stores the information of the tracking area; the information of the tracking area further includes information of a sub-area, and the sub-area belongs to a coverage area of the service gateway.

2. The communication method of claim 1, wherein the method further comprises:

if the tracking area information in the received broadcast message is not in the tracking area List TA List of the terminal, the terminal performs tracking area update TAU.

3. A method of communication, comprising:

the method comprises the steps that the access network equipment acquires information of a tracking area, and all or part of functional modules of the access network equipment are deployed in one of the following items: in an empty platform, a satellite or a communication device moving in high altitude, the information of the tracking area comprises the information of a service gateway; the service gateway is a ground gateway;

the access network equipment sends a broadcast message, wherein the broadcast message comprises the information of the tracking area; the information of the tracking area further includes information of a sub-area, and the sub-area belongs to a coverage area of the service gateway.

4. The communication method according to claim 3, wherein the obtaining information of the tracking area by the access network device comprises:

the access network equipment determines a service gateway; the service gateway is a ground gateway connected with the access network equipment, and the access network equipment is connected with only one ground gateway; or the service gateway is a gateway with the best signal strength in the N ground gateways, and the access network equipment is connected with the N ground gateways, wherein N is greater than 1, and N is an integer;

5. The communication method according to claim 3 or 4, wherein the access network device sends a broadcast message, comprising:

in a first time period, the access network equipment sends a first broadcast message, wherein the first broadcast message comprises information of a service gateway corresponding to the first time period;

in a second time period, the access network device sends a second broadcast message, where the second broadcast message includes information of a serving gateway corresponding to the second time period, and the information of the serving gateway included in the first broadcast message is different from the information of the serving gateway included in the second broadcast message.

6. The communication method according to claim 3 or 4, wherein the access network device sends a broadcast message, comprising:

7. A communications apparatus, comprising:

a communication unit, configured to receive a broadcast message from an access network device, where all or part of functional modules of the access network device are deployed in one of the following: in an empty platform, a satellite, or a communication device moving in high altitude, the broadcast message includes information of a tracking area, and the information of the tracking area includes information of a service gateway; the service gateway is a ground gateway;

a storage unit for storing information of the tracking area; the information of the tracking area further includes information of a sub-area, and the sub-area belongs to a coverage area of the service gateway.

8. The communications apparatus of claim 7, the apparatus further comprising: a processing unit for processing the received data,

the processing unit is configured to perform tracking area update TAU if the information of the tracking area in the received broadcast message is not in the tracking area List TA List of the storage unit.

9. A communications apparatus, comprising:

the processing unit is used for acquiring the information of the tracking area, and all or part of functional modules of the communication device are deployed in one of the following items: the information of the tracking area comprises the information of a service gateway in an empty platform, a satellite or a communication device moving in high altitude; the service gateway is a ground gateway;

a communication unit for transmitting a broadcast message including information of the tracking area; the information of the tracking area further includes information of a sub-area, and the sub-area belongs to a coverage area of the service gateway.

10. The communication apparatus according to claim 9, wherein the processing unit is configured to obtain information of a tracking area, and includes: for determining a serving gateway; the service gateway is a ground gateway connected with the communication device, and the communication device is connected with only one ground gateway; or the service gateway is the gateway with the best signal strength in the N ground gateways, and the communication device is connected with the N ground gateways, wherein N is greater than 1, and N is an integer;

and the tracking area information is obtained according to the service gateway information.

11. The communication apparatus according to claim 9 or 10, wherein the communication unit is configured to transmit a broadcast message, and comprises: the system comprises a first time interval and a second time interval, wherein the first time interval is used for receiving a first broadcast message, and the first broadcast message comprises information of a service gateway corresponding to the first time interval; and sending a second broadcast message in a second time interval, wherein the second broadcast message comprises the information of the service gateway corresponding to the second time interval, and the information of the service gateway included in the first broadcast message is different from the information of the service gateway included in the second broadcast message.

12. The communication apparatus according to claim 9 or 10, wherein the communication unit is configured to transmit a broadcast message, and comprises: the device comprises a first broadcast message sending unit, a second broadcast message sending unit and a third message sending unit, wherein the first broadcast message comprises information of a subregion corresponding to a first time period; and transmitting a fourth broadcast message in a fourth time period, wherein the fourth broadcast message comprises information of a sub-region corresponding to the fourth time period, and the information of the sub-region included in the third broadcast message is different from that included in the fourth broadcast message.

13. A readable storage medium characterized by comprising a program or instructions which, when executed, implement the communication method according to any one of claims 1 to 2, or implement the communication method according to any one of claims 3 to 6.