Communication method, communication apparatus, and computer storage medium

Abstract

A communication method, a communication apparatus, and a computer storage medium. The communication method comprises: determining that a first satellite is an anchor satellite of a terminal device, the anchor satellite being a satellite that establishes a service link with the terminal device and communicates with the terminal device on the basis of the service link, and a first access network device being deployed on the first satellite; and, receiving downlink information from the first access network device, and / or sending uplink information to the first access network device. The present application can reduce the complexity of forwarding context information of a terminal device and reduce the power consumption of the terminal device.

Description

Communication method, communication apparatus, and computer storage medium

[0001] The present application claims priority from the Chinese patent application No. 202411124779.8 filed on August 16, 2024, and entitled "Communication method, communication apparatus, and computer storage medium", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the field of communication technology, and in particular to a communication method, a communication apparatus, and a computer storage medium. BACKGROUND

[0003] In a radio access network (RAN) architecture of non-terrestrial networks (NTN), a satellite deploying an access network device can interact information with a terminal device on the ground through a service link, and interact information with an NTN gateway on the ground through a feeder link, and the NTN gateway on the ground can establish a communication connection with a core network device.

[0004] When the terminal device accesses using the satellite, there can be a discontinuous coverage scenario. For example, at T1, the satellite is above the terminal device, the terminal device is within the coverage of the satellite, the service link between the terminal device and the satellite is available, but the NTN gateway is not within the coverage of the satellite, so the feeder link between the satellite and the NTN gateway is unavailable, and the satellite cannot establish a communication connection with the core network device through the NTN gateway on the ground. At T2, the satellite moves above the NTN gateway, the feeder link between the NTN gateway and the satellite is available, but the terminal device is not within the coverage of the satellite, so the service link between the satellite and the terminal device is unavailable.

[0005] Currently, multiple satellites are deployed in the RAN architecture of NTN, and there is an inter-satellite link between the satellites. When a terminal device needs to send uplink information to the network, it accesses one of the multiple satellites and sends the uplink information to the accessed satellite. Since the feeder link between the accessed satellite and the NTN gateway on the ground is unavailable, the accessed satellite can forward the uplink information to other satellites through the inter-satellite link, so that the other satellites send the uplink information to the NTN gateway. For downlink information of the terminal device, the NTN gateway sends the downlink information of the terminal device to one satellite through the feeder link. Since the service link between the satellite and the terminal device is unavailable, the satellite can forward the downlink information to other satellites, so that the other satellites send the downlink information to the terminal device through the service link. As can be seen from the above, the satellite in communication with the terminal device is random. Since the communication between the terminal device and the satellite requires the context information of the terminal device, the context information of the terminal device needs to be forwarded between satellites, thereby increasing the complexity of forwarding the context information of the terminal device. SUMMARY

[0006] The purpose of the present application is to provide a communication method, a communication device and a computer storage medium. The satellite in communication with the terminal device is fixed, thereby avoiding the forwarding of the context information of the terminal device between satellites and reducing the complexity of forwarding the context information of the terminal device.

[0007] In a first aspect, a communication method is provided, applied to a terminal device, comprising:

[0008] determining a first satellite as an anchor satellite of the terminal device, the first satellite deploying a first access network device, the anchor satellite being a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link;

[0009] receiving downlink information from the first access network device, and / or sending uplink information to the first access network device.

[0010] In the method of the first aspect, the first satellite is used as an anchor satellite of the terminal device, that is, the terminal device is fixedly connected with the first satellite, such as receiving downlink information from the first satellite and / or sending uplink information to the first satellite. By fixing the satellite connected with the terminal device, the context information of the terminal device can be avoided to be forwarded between satellites, and the complexity of forwarding the context information of the terminal device is reduced. In addition, due to the fixed connection with the satellite, the terminal device does not need to always monitor the paging message in order to avoid missing the downlink information, thereby saving the power consumption of the terminal device. Since the terminal device needs to establish a service link with the fixed anchor satellite and communicate, the real-time performance of uplink information and / or downlink information transmission is affected, but for a service scenario with low real-time performance requirement, such as a data collection and reporting scenario in the Internet of Things, the communication method provided in the present application will not affect the uplink information and / or downlink information transmission, and better beneficial effects can be achieved.

[0011] In combination with the first aspect, in a possible implementation manner, the receiving downlink information from the first access network device and / or the sending uplink information to the first access network device comprises:

[0012] establishing a radio resource control (RRC) connection with the first access network device;

[0013] receiving downlink information from the first access network device based on the RRC connection and / or sending uplink information to the first access network device based on the RRC connection.

[0014] In this manner, when uplink information needs to be sent or downlink information needs to be received, the RRC connection is established with the first access network device, thereby avoiding the RRC connection to be always established, and the power consumption of the terminal device is saved.

[0015] In combination with the first aspect, in a possible implementation manner, the establishing the RRC connection with the first access network device comprises:

[0016] when the terminal device is located in the coverage of the first satellite and a broadcast message from the first access network device is received, establishing the RRC connection with the first access network device, wherein the broadcast message comprises an identifier of the first satellite.

[0017] In this manner, when it is determined that the terminal device is located in the coverage of the anchor satellite and the broadcast message comprising the identifier of the first satellite is received, the RRC connection is established, and the terminal device does not need to always monitor in order to avoid missing the downlink information, thereby saving the power consumption of the terminal device.

[0018] In combination with the first aspect, in a possible implementation manner, the determining that the first satellite is the anchor satellite of the terminal device comprises:

[0019] receiving first indication information, the first indication information indicating to establish an anchor relationship between the first satellite and the terminal device;

[0020] determining, according to the first indication information, the first satellite as an anchor satellite of the terminal device.

[0021] Implementing this mode, the network indicates to establish an anchor relationship between the first satellite and the terminal device, so as to facilitate the consistency of the anchor satellite determined by the network side and the terminal device.

[0022] In combination with the first aspect, in a possible implementation, the method further includes:

[0023] In a case where the terminal device is located in a coverage range of the first satellite and has not received a broadcast message from the first access network device in more than a preset number of times of listening, determining a second satellite as an anchor satellite of the terminal device.

[0024] Implementing this mode, when the terminal device cannot search for a broadcast message including an identifier of an anchor satellite, the anchor relationship between the first satellite and the terminal device is cancelled, and the second satellite is determined as the anchor satellite of the terminal device, without the need for the terminal device to continue searching for the first satellite, saving the power consumption of the terminal device and reducing the information transmission delay.

[0025] In combination with the first aspect, in a possible implementation, the method further includes:

[0026] receiving second indication information sent by the first access network device, the second indication information indicating that the first satellite is no longer an anchor satellite of the terminal device;

[0027] determining, according to the second indication information, a second satellite as an anchor satellite of the terminal device.

[0028] Implementing this mode, the network can actively cancel the anchor relationship between the first satellite and the terminal device, and the terminal device establishes an anchor relationship with the second satellite, so as to avoid the terminal device to continue searching for a broadcast message including an identifier of the first satellite, saving the power consumption of the terminal device and reducing the information transmission delay.

[0029] In combination with the first aspect, in a possible implementation, the determining of the second satellite as the anchor satellite of the terminal device includes:

[0030] establishing an RRC connection with a second access network device, the second access network device being deployed on a second satellite;

[0031] receiving third indication information from the second access network device, the third indication information indicating to establish an anchor relationship between the second satellite and the terminal device;

[0032] determining the second satellite as the anchor satellite of the terminal device according to the third indication information.

[0033] Implementing this mode, after canceling the anchor relationship between the first satellite and the terminal device, the anchor relationship between the second satellite and the terminal device can be continuously established, thereby facilitating the transmission of uplink information and downlink information of the terminal device and improving the communication success rate.

[0034] In a second aspect, a communication method is provided, applied to a core network device, including:

[0035] receiving downlink information, the downlink information being downlink information sent to a terminal device;

[0036] determining a first satellite as an anchor satellite of the terminal device, the first satellite being deployed with a first access network device, and the anchor satellite being a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link;

[0037] sending the downlink information to the first access network device.

[0038] Implementing the method of the second aspect, when the core network device receives the downlink information of the terminal device, the core network device sends the downlink information to the anchor satellite of the terminal device, and the anchor satellite of the terminal device communicates with the terminal device, thereby avoiding the forwarding of the context information of the terminal device between satellites and increasing complexity.

[0039] In combination with the second aspect, in a possible implementation, the method further includes:

[0040] receiving a first request message from the first access network device, the first request message being used to request to establish an anchor relationship between the first satellite and the terminal device;

[0041] sending a first response message to the first access network device, the first response message indicating to allow the establishment of the anchor relationship between the first satellite and the terminal device;

[0042] wherein after the establishment of the anchor relationship between the first satellite and the terminal device, the anchor satellite of the terminal device is the first satellite.

[0043] Implementing this mode, the core network device and the access network device interact, and the anchor satellite of the terminal device is determined as the first satellite, so that the core network device and the access network device both uniformly take the first satellite as the anchor satellite of the terminal device.

[0044] With reference to the second aspect, in a possible implementation manner, the method further includes:

[0045] receiving a second request message from the first access network device, the second request message being used for requesting that the first satellite is no longer an anchor satellite for the terminal device;

[0046] sending a second response message to the first access network device, the second response message indicating that the first satellite is allowed to be no longer the anchor satellite for the terminal device.

[0047] In this manner, the core network device and the access network device interact with each other to cancel the anchor relationship between the terminal device and the first satellite, and the core network device will not subsequently send downlink information of the terminal device to the first satellite.

[0048] In a third aspect, a communication method is provided, and the method is applied to an access network device, the access network device is deployed on a first satellite, and the method includes the following steps.

[0049] sending first indication information to a terminal device, the first indication information indicating that an anchor relationship between the first satellite and the terminal device is established;

[0050] After the anchor relationship between the first satellite and the terminal device is established, an anchor satellite of the terminal device is the first satellite, and the anchor satellite is a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link.

[0051] In this manner, the anchor relationship between the first satellite and the terminal device is established, and context information of the terminal device is prevented from being forwarded between satellites.

[0052] With reference to the third aspect, in a possible implementation manner, before the first indication information is sent to the terminal device, the method further includes the following steps.

[0053] sending a first request message to a core network device, the first request message being used for requesting that the anchor relationship between the first satellite and the terminal device is established;

[0054] receiving a first response message from the core network device, the first response message indicating that the anchor relationship between the first satellite and the terminal device is allowed to be established.

[0055] In this manner, the access network device and the core network device interact with each other, and the first satellite can also be uniformly determined as the anchor satellite of the terminal device.

[0056] With reference to the third aspect, in a possible implementation manner, after the first indication information is sent to the terminal device, the method further includes the following steps.

[0057] sending a second request message to the core network device, the second request message being used to request that the first satellite is no longer an anchor satellite for the terminal device;

[0058] receiving a second response message from the core network device, the second response message indicating that the first satellite is allowed to be no longer an anchor satellite for the terminal device.

[0059] In this way, the anchor relationship between the terminal device and the first satellite is cancelled through interaction between the core network device and the access network device, and the core network device will not subsequently send downlink information of the terminal device to the first satellite.

[0060] In combination with the third aspect, in a possible implementation manner, the method further includes:

[0061] sending second indication information to the terminal device, the second indication information indicating that the first satellite is no longer an anchor satellite for the terminal device.

[0062] In this way, the terminal device is indicated to cancel the anchor relationship between the first satellite and the terminal device, and the terminal device will not subsequently listen to a broadcast message including an identifier of the first satellite, thereby saving power consumption of the terminal device.

[0063] In the fourth aspect, an embodiment of the present application provides a communication apparatus applied to a terminal device, and including:

[0064] a processing unit configured to determine that a first satellite is an anchor satellite for the terminal device, the first satellite being deployed with a first access network device, and the anchor satellite being a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link;

[0065] a transceiver configured to receive downlink information from the first access network device, and / or send uplink information to the first access network device.

[0066] In the fifth aspect, an embodiment of the present application provides a communication apparatus applied to a core network device, and including:

[0067] a transceiver configured to receive downlink information, the downlink information being downlink information sent to a terminal device;

[0068] a processing unit configured to determine that a first satellite is an anchor satellite for the terminal device, the first satellite being deployed with a first access network device, and the anchor satellite being a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link;

[0069] the transceiver is further configured to send the downlink information to the first access network device.

[0070] In a sixth aspect, an embodiment of the present application provides a communication device applied to an access network device, the access network device is deployed on a first satellite, and the communication device comprises:

[0071] a transceiver configured to send first indication information to a terminal device, the first indication information indicating that an anchor relationship between the first satellite and the terminal device is established.

[0072] After the anchor relationship between the first satellite and the terminal device is established, an anchor satellite of the terminal device is the first satellite, and the anchor satellite is a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link.

[0073] In a seventh aspect, an embodiment of the present application provides a communication device, which comprises a processor and a memory, the processor and the memory are connected to each other, the memory is configured to store a computer program, and the processor is configured to execute the computer program to perform the method in the first aspect or any optional implementation manner of the first aspect, or to perform the method in the second aspect or any optional implementation manner of the second aspect, or to perform the method in the third aspect or any optional implementation manner of the third aspect.

[0074] In an eighth aspect, an embodiment of the present application provides a chip, which comprises a processor and an interface, the processor and the interface are coupled; the interface is configured to receive and / or output a signal, and the processor is configured to execute a code instruction to perform the method in the first aspect or any optional implementation manner of the first aspect, or to perform the method in the second aspect or any optional implementation manner of the second aspect, or to perform the method in the third aspect or any optional implementation manner of the third aspect.

[0075] In a ninth aspect, an embodiment of the present application provides a computer storage medium, which stores a computer program, the computer program comprises program instructions, and when a computer executes the program instructions, the method in the first aspect or any optional implementation manner of the first aspect is implemented, or the method in the second aspect or any optional implementation manner of the second aspect is implemented, or the method in the third aspect or any optional implementation manner of the third aspect is implemented.

[0076] In a tenth aspect, an embodiment of the present application provides a computer program product, which comprises a computer program or computer code, and when the computer program product is run on a computer, the method in the first aspect or any optional implementation manner of the first aspect is implemented, or the method in the second aspect or any optional implementation manner of the second aspect is implemented, or the method in the third aspect or any optional implementation manner of the third aspect is implemented.

[0077] In an eleventh aspect, an embodiment of the present application provides a communication system, which includes at least two of a first communication device, a second communication device and a third communication device.

[0078] The technical solutions provided in the fourth to eleventh aspects of the present application have the beneficial effects of the technical solutions provided in the first to third aspects of the present application, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0079] FIG. 1 is a communication system provided by an embodiment of the present application;

[0080] FIG. 2 is a network architecture diagram of deploying an access network device on a satellite according to an embodiment of the present application;

[0081] FIG. 3 is a schematic diagram of the positions among a satellite, a terminal device and an NTN gateway according to an embodiment of the present application;

[0082] FIG. 4 is a flowchart of a communication method provided by an embodiment of the present application;

[0083] FIG. 5 is a flowchart of another communication method provided by an embodiment of the present application;

[0084] FIG. 6 is a flowchart of still another communication method provided by an embodiment of the present application;

[0085] FIG. 7 is a flowchart of still another communication method provided by an embodiment of the present application;

[0086] FIG. 8 is a flowchart of establishing an anchor relationship provided by an embodiment of the present application;

[0087] FIG. 9 is a flowchart of uplink data transmission provided by an embodiment of the present application;

[0088] FIG. 10 is a flowchart of downlink data transmission provided by an embodiment of the present application;

[0089] FIG. 11 is a flowchart of canceling an anchor relationship provided by an embodiment of the present application;

[0090] FIG. 12 is a structural diagram of a communication device provided by an embodiment of the present application;

[0091] FIG. 13 is a structural diagram of another communication device provided by an embodiment of the present application;

[0092] FIG. 14 is a structural diagram of still another communication device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0093] In the embodiments of this application, unless otherwise specified, the character " / " represents a relationship of one or the other of the associated objects before and after. For example, A / B can represent A or B. The "and / or" describes the associated relationship of the associated objects, which means that there can be three relationships. For example, A and / or B can represent three cases: A exists alone, A and B exist together, and B exists alone.

[0094] It should be noted that the "first", "second", and the like referred to in the embodiments of this application are only used for distinguishing purposes of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features, nor can it be understood as indicating or implying an order.

[0095] In the embodiments of this application, "at least one" means one or more, and "multiple" means two or more. In addition, "at least one of the following" or the like means any combination of these items, which can include any combination of single item or multiple items. For example, at least one of A, B or C can represent A, B, C, A and B, A and C, B and C, or A, B and C. Wherein, each of A, B and C can be an element or a set containing one or more elements.

[0096] In the embodiments of this application, "example", "in some embodiments", "in another embodiment" and the like are used to represent as an example, illustration or description. Any embodiment or design scheme described as "example" in this application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the word "example" is intended to present the concept in a specific way.

[0097] In the embodiments of this application, "of", "corresponding" and "corresponding" can be mixed sometimes. It should be pointed out that the meanings to be expressed are consistent when the distinction is not emphasized. In the embodiments of this application, communication and transmission can be mixed sometimes. It should be pointed out that the meanings to be expressed are consistent when the distinction is not emphasized. For example, transmission can include sending and / or receiving, and can be a noun or a verb.

[0098] In the embodiments of this application, equal to can be used with greater than, which is applicable to the technical solutions adopted when greater than. It can also be used with less than, which is applicable to the technical solutions adopted when less than. It should be noted that when equal to is used with greater than, it cannot be used with less than; when equal to is used with less than, it cannot be used with greater than.

[0099] The communication method provided in the present application can be applied to a long term evolution (LTE) system, a 5G NR (5G New Radio) system, a 6G system, and subsequent evolution systems, and the present application is not limited thereto. As shown in FIG. 1, the communication system at least includes terminal devices, access network devices, and core network devices.

[0100] The terminal device can also be referred to as a terminal, a user equipment (UE), a wireless terminal device, a mobile terminal (MT) device, a subscriber unit, a subscriber station, a mobile station (MS), a mobile station (mobile), a remote station, an access point (AP), a remote terminal, an access terminal, a user terminal, a user agent, or a user device, etc. In addition, the terminal device can be a mobile phone, a tablet computer (Pad), a computer with wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal in industrial control, a wireless terminal in self driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc. It should be understood that embodiments of the present application do not limit the specific technology and specific device form of the terminal device. The terminal device in the present application can be any one of the above devices or chips, and the specific device is not limited here. Whether as a device or as a chip, the terminal device can be manufactured, sold or used as an independent product. In the present embodiment and subsequent embodiments, the terminal device is taken as an example for introduction.

[0101] The access network device can be any device with wireless transceiver function, and can be used to be responsible for functions related to air interface, such as wireless link maintenance function, wireless resource management function, and part of mobility management function. In addition, the access network device can also be configured with a baseband unit (BBU) with baseband signal processing function. For example, the access network device can be a radio access network (RAN) currently serving the terminal device. At present, some common examples of the access network device are: Node B (NB), evolved Node B (eNB), next generation Node B (gNB) in 5G new radio (NR) system, node (for example, xNodeB) in 6G system, transmission reception point (TRP), radio network controller (RNC), base station controller (BSC), base transceiver station (BTS), home base station (for example, home evolved NodeB or home Node B (HNB)), and the like. In addition, in a network structure such as cloud radio access network (CloudRAN) or open radio access network (ORAN), the access network device can be a device including a centralized unit (CU) (also referred to as a control unit) and / or a distributed unit (DU). It should be understood that the access network device in the embodiments of the present application can be any of the above devices or chips in the above devices, and the specific embodiments are not limited here. Whether as a device or as a chip, the access network device can be manufactured, sold or used as an independent product. In the present embodiment and subsequent embodiments, the access network device is taken as an example for introduction.

[0102] The core network device refers to a device in a core network (CN) that provides service support for a terminal device. Currently, some common examples of the core network device are: an access and mobility management function (AMF) entity, a session management function (SMF) entity, a user plane function (UPF) entity, a mobility management entity (MME), and the like, which are not listed one by one here. Among them, the AMF entity can be responsible for access management and mobility management of the terminal device; the SMF entity can be responsible for session management, such as session establishment of a user; the UPF entity can be a functional entity of a user plane, mainly responsible for connecting an external network; and the MME is mainly responsible for signaling processing and the like.

[0103] It should be noted that the entity in the present application can also be referred to as a network element or a functional entity. For example, the AMF entity can also be referred to as an AMF network element or an AMF functional entity; for another example, the SMF entity can also be referred to as an SMF network element or an SMF functional entity, and the like.

[0104] For example, the communication method proposed in the present application can be applied to a non-terrestrial communication network (NTN) architecture. For example, the non-terrestrial communication network (NTN-based NG-RAN architectures) defined in the 3GPP protocol based on the NG-RAN architecture. At this time, part or all of the functions of the foregoing access network device can be implemented by a non-terrestrial communication network device (such as a satellite, a tethered unmanned aerial system (TUA), etc.), that is, the access network device can be deployed on the non-terrestrial communication network device. It should be noted that the present application takes the satellite as an example for description, but the present application is not limited thereto. The non-terrestrial communication network device can also be other, that is, the satellite described in the embodiments of the present application can also be replaced by other non-terrestrial communication network devices.

[0105] As shown in FIG. 2, a network architecture for deploying an access network device on a satellite is provided in the embodiments of the present application. The network architecture includes a terminal device, a satellite, an NTN gateway (which can also be referred to as a ground station, a gateway, or a gateway station), and a core network device, and the access network device is deployed on the satellite.

[0106] The satellite can be a geostationary earth orbit (GEO) satellite, a medium earth orbit (MEO) satellite or a low earth orbit (LEO) satellite in a non-geostationary earth orbit (NGEO), or a high altitude platform station (HAPS), etc. The specific type of satellite is not limited in the present application.

[0107] The NTN gateway in the embodiments of the present application can be used to connect the satellite and the core network device on the ground. The communication link between the NTN gateway and the satellite can be referred to as a feeder link (or a feedback link); the communication link between the satellite and the terminal device can be referred to as a service link.

[0108] It can be understood that FIG. 2 only shows one satellite and one NTN gateway, and in actual use, a multi-satellite and / or multi-NTN gateway architecture can be adopted as needed. Each satellite can provide service to one or more terminal devices, each satellite can correspond to one or more NTN gateways, each NTN gateway can correspond to one or more satellites, etc., which are not specifically limited in the present application.

[0109] Since the satellite will move continuously, the relative positions between the satellite and the terminal device or the NTN gateway will change continuously. For example, as shown in (a) of FIG. 3, at t1, the satellite is above the terminal device, the service link between the satellite and the terminal device is available, but the feeder link between the satellite and the NTN gateway is unavailable. At t2, as shown in (b) of FIG. 3, the satellite is above the NTN gateway, the feeder link between the satellite and the NTN gateway is available, but the service link between the satellite and the terminal device is unavailable. The t2 time can be after the t1 time.

[0110] For services with low real-time requirements, uplink information and / or downlink information can be transmitted through a store-and-forward manner. Taking the terminal device camping network process as an example, the uplink information is an attach signaling, and the downlink information is an attach accept message.

[0111] The terminal device sends the attach signaling to the satellite 1 through the service link, the satellite 1 stores the attach signaling, and waits for the feeder link between the satellite 1 and the NTN gateway to be available, and then the satellite 1 sends the attach signaling to the core network device, which can be, for example, an MME. It can be understood that the satellite 1 can also send the attach signaling to other satellites, for example, to the satellite 2, and the satellite 2 forwards the attach signaling to the core network device.

[0112] The core network device sends the attach accept message to the satellite 1, the satellite 1 stores the attach accept message, and waits for the service link between the satellite 1 and the terminal device to be available, and then the satellite 1 sends the attach accept message to the terminal device. It can be understood that the satellite 1 can also send the attach accept message to other satellites, for example, to the satellite 3, and the satellite 3 forwards the attach accept message to the terminal device.

[0113] In a multi-satellite deployment scenario, the satellite in communication with the terminal device is not fixed, for example, the satellite 1 stores and forwards the uplink information and / or downlink information of the terminal device the first time, and the satellite 2 stores and forwards the uplink information and / or downlink information of the terminal device the second time. Since the context information of the terminal device is needed when the terminal device communicates with the satellite, the satellite in communication with the terminal device is not fixed, which will cause the context information of the terminal device to be forwarded between satellites, increasing complexity, and the terminal device will constantly listen to the paging message in order not to miss the downlink information, increasing the power consumption of the terminal device.

[0114] To solve the above technical problems, an embodiment of the present application proposes to set an anchor satellite for the terminal device, which is fixed to communicate with the terminal device. For example, the terminal device can receive downlink information from the access network device deployed on the anchor satellite, and / or the terminal device can send uplink information to the access network device deployed on the anchor satellite, and the anchor satellite can store and forward the uplink information and / or downlink information. Since the satellite in communication with the terminal device is fixed, the context information of the terminal device can be avoided to be forwarded between satellites, reducing complexity. The terminal device does not need to constantly listen to the paging message, saving the power consumption of the terminal device.

[0115] The following explains some terms related to the embodiments of the present application to facilitate understanding by those skilled in the art.

[0116] 1. ephemeris information

[0117] Ephemeris information, which can also be referred to as ephemeris, almanac, almanac, etc., is information used to locate the position of a celestial body at any time. The terminal device can search for a network according to the ephemeris information of the satellite, thereby improving the user experience. The ephemeris information of the satellite mainly includes orbital plane parameters and satellite level parameters. It should be understood that in the embodiments of the present application, the ephemeris information of the satellite can also be referred to as ephemeris parameters, satellite ephemeris parameters, or other possible names, which are not limited in the present application.

[0118] 2, anchor satellite

[0119] The anchor satellite in the embodiments of the present application can also be referred to as an anchor satellite cell. The anchor satellite is a fixed satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link. When the terminal device needs to send uplink information, the terminal device sends the uplink information to the anchor satellite through the service link. Similarly, the downlink information sent by the network to the terminal device is also sent to the anchor satellite, so that the anchor satellite sends the downlink information to the terminal device through the service link.

[0120] It should be noted that each technical solution (or referred to as each embodiment) of the present application can be independently implemented or can be implemented based on certain internal relationship. The present application does not make any limitation. And the various terms and definitions between the embodiments can be mutually quoted. In each embodiment of the present application, different implementations can be combined or independently implemented.

[0121] Please refer to FIG. 4, which is a flow diagram of a communication method provided by an embodiment of the present application. As shown in FIG. 4, the communication method of the embodiment can include the following steps:

[0122] 401, the terminal device determines that the first satellite is the anchor satellite of the terminal device.

[0123] Among them, the first satellite is deployed with the first access network device, and correspondingly, the cell covered by the first access network device is the anchor satellite cell.

[0124] The first satellite as the anchor satellite of the terminal device can be indicated by the network. For example, the first access network device can send first indication information to the terminal device, the first indication information indicating to establish an anchor relationship between the first satellite and the terminal device. The terminal device can determine the first satellite as the anchor satellite of the terminal device according to the first indication information.

[0125] 402, the terminal device receives downlink information from the first access network device, and / or sends uplink information to the first access network device.

[0126] After determining the first satellite as the anchor satellite of the terminal device, the terminal device subsequently receives downlink information from the first access network device deployed on the first satellite, and / or sends uplink information to the first access network device deployed on the first satellite.

[0127] The uplink information can include, but is not limited to, uplink data and / or uplink signaling. The downlink information can include, but is not limited to, downlink data and / or downlink signaling. The processes of the terminal device sending uplink information and receiving downlink information are respectively illustrated as follows:

[0128] The process of the terminal device sending uplink information is illustrated as follows: when the terminal device is in an idle state and there is uplink information to be sent to the network, the terminal device listens to a broadcast message, which includes the identity of the satellite. The terminal device determines whether the broadcast message is sent by the anchor satellite (i.e., the first satellite) of the terminal device according to the identity of the satellite contained in the broadcast message. If the terminal device receives the broadcast message including the identity of the anchor satellite (i.e., the first satellite), it means that the first access network device on the first satellite can be accessed, and the terminal device can establish a radio resource control (RRC) connection with the first access network device deployed on the first satellite, so as to send the uplink information to the first access network device based on the RRC connection. Correspondingly, the first access network device receives the uplink information, and since the feeder link between the first satellite and the NTN gateway is unavailable, the first access network device can store the uplink information and send it to the core network device when the feeder link between the first satellite and the NTN gateway is available. Illustratively, the first access network device can also send the uplink information to other satellites for sending to the core network device, which is not limited in the present application.

[0129] After the terminal device sends the uplink information to the anchor satellite (i.e., the first satellite), the terminal device can disconnect the RRC connection with the first access network device, which can be specifically that the first access network device sends an RRC connection release message or an RRC connection suspend message to the terminal device.

[0130] In order to save the power consumption of the terminal device, the terminal device can not always listen to the broadcast message. The terminal device can determine the time when the terminal device is located in the coverage range of the first satellite according to the ephemeris information of the first satellite, and only start listening to the broadcast message and receiving the broadcast message from the first access network device when it is determined that the terminal device is located in the coverage range of the first satellite, so as to save power consumption.

[0131] The terminal device receives the downlink information in the following process: the terminal device listens to the broadcast message, and the broadcast message includes the identity of the satellite. The terminal device determines whether the broadcast message is sent by the anchor satellite (i.e., the first satellite) of the terminal device according to the identity of the satellite included in the broadcast message. If the terminal device receives the broadcast message including the identity of the anchor satellite (i.e., the first satellite), the terminal device camps on the anchor satellite cell and continues to listen to whether there is a paging message of the terminal device. If the terminal device receives the paging message of the terminal device, the terminal device can establish an RRC connection with the first access network device deployed on the first satellite, so as to receive the downlink information based on the RRC connection.

[0132] After the terminal device receives the downlink information, the terminal device can disconnect the RRC connection between the terminal device and the first access network device, specifically, the first access network device sends an RRC connection release message or an RRC connection suspend message to the terminal device.

[0133] In order to save the power consumption of the terminal device, the terminal device can also not always listen to the broadcast message. The terminal device can determine the time when the terminal device is located in the coverage range of the first satellite according to the ephemeris information of the first satellite, and only start to listen to the broadcast message and receive the broadcast message from the first access network device when it is determined that the terminal device is located in the coverage range of the first satellite, so as to save the power consumption.

[0134] Please refer to FIG. 5, which is a flowchart of another communication method provided by an embodiment of the present application. As shown in FIG. 5, the communication method of the embodiment can include the following steps:

[0135] 501, the core network device receives downlink information.

[0136] The downlink information is the downlink information of the terminal device. For example, the downlink information includes the identity of the terminal device.

[0137] The downlink information can be the downlink information sent by the application server to the core network device.

[0138] 502, the core network device determines that the anchor satellite of the terminal device is the first satellite.

[0139] The core network device can store the anchor relationship between the first satellite and the terminal device, and the anchor relationship between the first satellite and the terminal device indicates that the anchor satellite of the terminal device is the first satellite. When the core network device receives the downlink information of the terminal device, the core network device can determine that the anchor satellite of the terminal device is the first satellite according to the stored anchor relationship between the first satellite and the terminal device. The first access network device is deployed on the first satellite.

[0140] 503, the core network device sends the downlink information to the first access network device.

[0141] The core network device sends the downlink information to the first access network device. Specifically, the downlink information can be sent to the first access network device deployed on the first satellite when the feeder link between the first satellite and the NTN gateway is available. The first access network device can store the downlink information to wait for the service link between the first satellite and the terminal device to be available, and then send the downlink information to the terminal device.

[0142] 504, the first access network device sends the downlink information to the terminal device.

[0143] The first access network device can send a paging message to the terminal device, and the paging message indicates the terminal device to receive the downlink information. When the terminal device receives the paging message, the terminal device establishes an RRC connection with the first access network device, and receives the downlink information based on the RRC connection. It can be understood that before the terminal device receives the paging message, the terminal device can receive a broadcast message from the first access network device, and the broadcast message includes the identity of the first satellite. When the terminal device determines that the broadcast message is sent by the anchor satellite (i.e., the first satellite), the terminal device camps on the cell covered by the first access network device and receives the paging message.

[0144] Please refer to FIG. 6, which is a flowchart of another communication method provided by an embodiment of the present application. As shown in FIG. 6, the communication method of the embodiment can include the following steps. It can be understood that in some embodiments, the following steps can also be included, for example, only steps 601-604 can be included to establish the anchor relationship between the first satellite and the terminal device, for another example, steps 601-604 and steps 606 and 607 can be included, for another example, only steps 606-612 can be included, and so on:

[0145] 601, the first access network device sends a first request message to the core network device.

[0146] The first request message is used to request to establish the anchor relationship between the first satellite and the terminal device.

[0147] For example, the first access network device can send the first request message to the core network device when the terminal device establishes an RRC connection with the first access network device.

[0148] In some embodiments, the terminal device can also send a request to the first access network device to request to establish the anchor relationship. The first access network device can send the first request message to the core network device according to the request sent by the terminal device.

[0149] For example, the first request message can include at least the identity of the terminal device and the identity of the first satellite.

[0150] 602, the core network device sends a first response message to the first access network device.

[0151] The first response message indicates that the anchor relationship between the first satellite and the terminal device is allowed to be established.

[0152] If the core network device allows the anchor relationship between the first satellite and the terminal device to be established, the core network device can send a first response message to the first access network device, and the first response message indicates that the anchor relationship between the first satellite and the terminal device is allowed to be established.

[0153] The core network device also stores the anchor relationship between the first satellite and the terminal device, and the anchor relationship indicates that the anchor satellite of the terminal device is the first satellite. For example, the core network device stores a mapping relationship between the identifier of the terminal device and the identifier of the first satellite.

[0154] 603, the first access network device sends first indication information to the terminal device.

[0155] The first indication information indicates that the anchor relationship between the first satellite and the terminal device is established.

[0156] For example, the first indication information can be carried in an RRC connection release message.

[0157] 604, the terminal device determines that the first satellite is the anchor satellite of the terminal device according to the first indication information.

[0158] The terminal device receives the first indication information, stores the anchor relationship between the first satellite and the terminal device, and for example, the terminal device stores the identifier of the first satellite.

[0159] 605, the terminal device receives downlink information from the first access network device, and / or sends uplink information to the first access network device.

[0160] After the terminal device sends the uplink information to the first access network device, or after the terminal device receives the downlink information, the terminal device disconnects the RRC connection. Specifically, the first access network device can send an RRC connection release message to the terminal device, and the terminal device can send an RRC connection release confirmation message to the first access network device.

[0161] 606, when it is determined that the terminal device is located in the coverage range of the first satellite, the terminal device starts to listen to the broadcast message.

[0162] When it is determined that the terminal device is located in the coverage range of the first satellite according to the ephemeris information of the first satellite, the terminal device can listen to the broadcast message. For example, when the terminal device needs to send uplink information, the terminal device listens to the broadcast message, or the terminal device listens to the broadcast message in order to receive downlink information.

[0163] 607, if the broadcast message including the identity of the first satellite is not received for more than a preset number of times, it is determined that the first satellite is not the anchor satellite of the terminal device.

[0164] If the terminal device does not receive the broadcast message including the identity of the first satellite for more than a preset number of times, the terminal device can no longer regard the first satellite as the anchor satellite of the terminal device. Further, the terminal device can perform steps 608-612 to establish the anchor relationship between the second satellite and the terminal device. That is, if the broadcast message including the identity of the first satellite is not received for more than a preset number of times, the second satellite can be determined as the anchor satellite of the terminal device, and the specific determination method can refer to steps 608-612.

[0165] 608, the terminal device establishes an RRC connection between the terminal device and the second access network device deployed on the second satellite.

[0166] The terminal device can camp on the second access network device and establish an RRC connection with the second access network device. For example, the terminal device can request the second access network device to establish the anchor relationship between the second satellite and the terminal device.

[0167] 609, the second access network device sends a third request message to the core network device.

[0168] The third request message is used to request to establish the anchor relationship between the second satellite and the terminal device. The second request message can include at least the identity of the terminal device and the identity of the second satellite.

[0169] 610, the core network device sends a third response message to the second access network device.

[0170] The second response message indicates that the anchor relationship between the second satellite and the terminal device is allowed to be established.

[0171] If the core network device allows the anchor relationship between the second satellite and the terminal device to be established, the core network device sends a second response message to the second access network device, which indicates that the anchor relationship between the second satellite and the terminal device is allowed to be established.

[0172] The core network device also stores the anchor relationship between the second satellite and the terminal device, which indicates that the anchor satellite of the terminal device is the second satellite.

[0173] In some embodiments, the core network device can cancel the anchor relationship between the first satellite and the terminal device, for example, delete the anchor relationship between the first satellite and the terminal device. When the core network device receives the downlink information of the terminal device, the core network device can send the downlink information to the second access network device deployed on the second satellite.

[0174] In some embodiments, the core network device can send a notification message to the first access network device, the notification message being used to notify that the anchor relationship between the first satellite and the terminal device is cancelled.

[0175] 611. The second access network device sends third indication information to the terminal device, the third indication information indicating to establish the anchor relationship between the second satellite and the terminal device.

[0176] For example, the first indication information can be carried in an RRC connection release message.

[0177] 612. The terminal device determines the second satellite as the anchor satellite of the terminal device according to the third indication information.

[0178] The terminal device can update the anchor satellite to the second satellite, and subsequently listen to the broadcast message including the identifier of the second satellite.

[0179] Please refer to FIG. 7, which is a flow diagram of another communication method provided by the embodiments of the present application. As shown in FIG. 7, the communication method of the embodiments can include the following steps. It can be understood that in some embodiments, some of the following steps can be included, for example, only steps 701-705 can be included, for another example, only steps 701-704 and steps 706-708 can be included, for another example, only steps 701-704 and steps 706-713 can be included, and so on:

[0180] 701. The first access network device sends a first request message to the core network device.

[0181] The first request message is used to request to establish the anchor relationship between the first satellite and the terminal device.

[0182] 702. The core network device sends a first response message to the first access network device.

[0183] The first response message indicates to allow to establish the anchor relationship between the first satellite and the terminal device.

[0184] 703. The first access network device sends first indication information to the terminal device.

[0185] The first indication information indicates to establish the anchor relationship between the first satellite and the terminal device.

[0186] 704. The terminal device determines the first satellite as the anchor satellite of the terminal device according to the first indication information.

[0187] 705. The terminal device receives downlink information from the first access network device, and / or sends uplink information to the first access network device.

[0188] The steps 701-705 of the embodiment of the present application refer to the steps 601-605 of the embodiment of FIG. 6, which will not be described herein.

[0189] 706. The first access network device sends a second request message to the core network device.

[0190] The second request message is used to request to cancel the anchor relationship between the first satellite and the terminal device. The second request message used to request to cancel the anchor relationship between the first satellite and the terminal device can be understood as the second request message used to request that the first satellite is no longer an anchor satellite of the terminal device.

[0191] The first access network device determines that the anchor relationship between the first satellite and the terminal device needs to be canceled. For example, the first access network device detects that the number of terminal devices taking the first satellite as an anchor satellite exceeds a preset threshold, and then the anchor relationship between one or more terminal devices and the first satellite can be canceled.

[0192] Specifically, the first access network device sends a second request message to the core network device, and the second request message includes the identifier of the terminal device whose anchor relationship needs to be canceled and the identifier of the first satellite.

[0193] 707. The core network device sends a second response message to the first access network device.

[0194] The second response message indicates that the anchor relationship between the first satellite and the terminal device is allowed to be canceled. The second response message indicating that the anchor relationship between the first satellite and the terminal device is allowed to be canceled can be understood as the second response message indicating that the first satellite is allowed to be no longer an anchor satellite of the terminal device.

[0195] If the core network device allows the anchor relationship between the first satellite and the terminal device to be canceled, the second response message is sent.

[0196] 708. The first access network device sends second indication information to the terminal device.

[0197] The second indication information indicates that the anchor relationship between the first satellite and the terminal device is canceled. The second indication information indicating that the anchor relationship between the first satellite and the terminal device is canceled can be understood as the second indication information indicating that the first satellite is no longer an anchor satellite of the terminal device.

[0198] The second indication information can be carried in the RRC connection release message or the RRC connection rejection establishment message. After receiving the second indication information, the terminal device can no longer take the first satellite as the anchor satellite of the terminal device. Further, the terminal device can perform steps 709-713 to establish the anchor relationship between the second satellite and the terminal device. That is, the terminal device can determine the second satellite as the anchor satellite of the terminal device according to the second indication information, and the specific determination manner can refer to steps 709-713.

[0199] 709. The terminal device establishes an RRC connection between the terminal device and a second access network device, and the second access network device is deployed on a second satellite.

[0200] 710. The second access network device sends a third request message to a core network device.

[0201] 711. The core network device sends a third response message to the second access network device.

[0202] 712. The second access network device sends third indication information to the terminal device, and the third indication information indicates to establish the anchor relationship between the second satellite and the terminal device.

[0203] 713. The terminal device determines the second satellite as the anchor satellite of the terminal device according to the third indication information.

[0204] The steps 709-713 of the embodiments of the present application refer to the steps 608-612 of the embodiment of FIG. 6, and will not be described here.

[0205] The following illustrates the processes of anchor relationship establishment, uplink information transmission, downlink information transmission, and anchor relationship cancellation. The following takes the terminal device as UE, the access network device as eNB, and the core network device as MME as an example:

[0206] Referring to FIG. 8, the process diagram of the anchor relationship establishment provided by the embodiments of the present application includes the following steps:

[0207] 801. The eNB1 sends a broadcast message, and the broadcast message includes the identifier of the satellite 1. Correspondingly, the UE receives the broadcast message.

[0208] The broadcast message can be a system broadcast message, and the broadcast message includes the identifier of the satellite 1 where the eNB1 is located. The eNB1 is deployed on the satellite 1.

[0209] 802. The terminal device establishes an RRC connection with the eNB1.

[0210] The terminal device can camp on the eNB1 and establish an RRC connection with the eNB1.

[0211] 803, the eNB 1 sends a first request message to the MME.

[0212] The first request message requests to establish an anchor relationship between the UE and the satellite 1.

[0213] The first request message can comprise an identity of the UE and an identity of the satellite 1. For example, the first request message can be an anchor relationship establishment request message.

[0214] 804, the MME stores the anchor relationship between the UE and the satellite 1.

[0215] Specifically, the MME storing the anchor relationship between the UE and the satellite 1 can be understood as that the MME can store a mapping relationship between the identity of the UE and the identity of the satellite 1.

[0216] 805, the MME sends a first response message to the eNB 1.

[0217] The first response message indicates that the anchor relationship between the UE and the satellite 1 is allowed to be established.

[0218] The first response message can also be understood as a confirmation message, i.e., confirming the establishment of the anchor relationship between the UE and the satellite 1, and the first response message can be an anchor relationship establishment confirmation message.

[0219] 806, the eNB 1 sends an RRC connection release message to the UE.

[0220] The RRC connection release message can comprise first indication information, and the first indication information is used to indicate the establishment of the anchor relationship between the UE and the satellite 1, i.e., the satellite 1 where the eNB 1 is located is the anchor satellite of the UE.

[0221] 807, the UE determines the satellite 1 as the anchor satellite and stores the identity of the satellite 1.

[0222] The UE establishes the anchor relationship between the UE and the satellite 1, for example, can be storing the identity of the satellite 1. The cell covered by the satellite 1 can be referred to as an anchor satellite cell, and the UE can also store the identity of the anchor satellite cell, i.e., the identity of the cell covered by the satellite 1, so as to facilitate subsequent search of the broadcast message to determine whether the broadcast message is sent by the anchor satellite. For example, if the searched broadcast message comprises the identity of the cell and the identity of the cell covered by the satellite 1 stored by the UE match, it is determined that the broadcast message is sent by the anchor satellite.

[0223] Please refer to FIG. 9, which is a flow diagram of uplink data transmission provided by the embodiment of the present application. The flow of uplink data transmission comprises the following steps:

[0224] 901, the UE determines whether the UE is in the coverage of the eNB 1 according to the ephemeris information of the satellite 1, and starts to listen to the broadcast message when it is determined that the UE is in the coverage of the eNB 1.

[0225] The terminal device can start to listen to the broadcast message only when it is determined that the UE is in the coverage of the eNB1, and the terminal device does not need to listen to the broadcast message all the time, which can save the power consumption of the terminal device.

[0226] 902, the eNB1 sends a broadcast message. The broadcast message includes the identification of the satellite 1. Correspondingly, the UE receives the broadcast message.

[0227] 903, the UE reads the identification of the satellite 1 in the broadcast message, and determines that the broadcast message is sent by the eNB1 deployed on the anchor satellite of the UE.

[0228] 904, an RRC connection between the UE and the eNB1 is established.

[0229] The UE can match the identification of the satellite included in the broadcast message with the identification of the satellite stored by the UE, and if the match is successful, it is determined that the broadcast message is the broadcast message sent by the eNB1 deployed on the anchor satellite.

[0230] For example, the identification of the satellite 1 included in the broadcast message sent by the eNB1 matches the identification of the satellite stored by the terminal device, the terminal device camps on the eNB1, and an RRC connection between the terminal device and the eNB1 is established.

[0231] 905, the UE sends uplink information to the eNB1.

[0232] The UE can send the uplink information to the eNB1 through the control plane or the user plane, the eNB1 can store the uplink information, and send the uplink information to the core network when the feeder link between the eNB1 and the NTN gateway is available. Alternatively, the eNB1 can also send the uplink information to other eNBs deployed on the satellite, so that the other eNBs deployed on the satellite send the uplink information to the core network.

[0233] 906, the eNB1 sends an RRC connection release message or an RRC connection suspend message to the UE.

[0234] Please refer to FIG. 10, which is a flowchart of downlink data transmission provided by an embodiment of the present application. The flow of downlink data transmission includes the following steps:

[0235] 1001, the MME sends downlink information to the eNB1.

[0236] The downlink information can be downlink information sent by an application server to the UE. The MME receives the downlink information, and according to the stored anchor relationship between the UE and the satellite 1, the MME can send the downlink information to the eNB1 deployed on the satellite 1. Specifically, the downlink information can be sent to the eNB1 when the feeder link between the satellite 1 and the NTN gateway is available, and the eNB1 stores the downlink information.

[0237] In order to send the downlink information to the UE, the eNB1 can send a paging message, which instructs the UE to receive the downlink information.

[0238] 1002, the UE determines whether the UE is in the coverage of the eNB1 according to the ephemeris information of the satellite 1, and starts to listen to the broadcast message when it is determined that the UE is in the coverage of the eNB1.

[0239] The UE starts to listen to the broadcast message only when it is determined that the UE is in the coverage of the eNB1, and the terminal device does not need to listen to the broadcast message all the time, which can save the power consumption of the terminal device.

[0240] 1003, the eNB1 sends the broadcast message.

[0241] The broadcast message includes the identification of the satellite 1. Correspondingly, the UE receives the broadcast message.

[0242] 1004, the UE reads the identification of the satellite 1 in the broadcast message, and determines that the broadcast message is sent by the anchor satellite for the UE.

[0243] 1005, the eNB1 sends the paging message.

[0244] The paging message instructs the UE to receive the downlink information. Correspondingly, the UE receives the paging message.

[0245] The UE receives the paging message and the broadcast message sent by the eNB1 and including the identification of the satellite 1, and performs step 1006, i.e., establishes the RRC connection between the UE and the eNB1.

[0246] 1006, the RRC connection between the UE and the eNB1 is established.

[0247] 1007, the eNB1 sends the downlink information to the UE.

[0248] Correspondingly, the UE receives the downlink information sent by the eNB1.

[0249] 1008, the eNB1 sends the RRC connection release message or the RRC connection suspend message to the UE.

[0250] Please refer to FIG. 11, which is a flowchart of the anchor relationship cancellation provided by the embodiment of the present application. It needs to be explained that the UE can actively cancel the anchor relationship between the UE and the satellite 1, which is shown in steps 1101-1102, or the eNB1 can actively cancel the anchor relationship between the UE and the satellite 1, which is shown in steps 1103-1105, and the following will be described in detail.

[0251] 1101, the UE determines whether the UE is in the coverage of the eNB1 according to the ephemeris information of the satellite 1, and starts to listen to the broadcast message when it is determined that the UE is in the coverage of the eNB1.

[0252] The UE starts to listen to the broadcast message only when it is determined that the UE is in the coverage of the eNB1, and the terminal device does not need to listen to the broadcast message all the time, which can save the power consumption of the terminal device.

[0253] 1102, if the UE does not listen to the broadcast message including the identifier of the satellite 1 for more than a preset number of times, it is determined to cancel the anchor relationship between the UE and the satellite 1.

[0254] In an implementation manner, when the UE listens to the broadcast message, if the UE does not listen to the broadcast message including the identifier of the satellite 1, the UE can continue to listen to the broadcast message after a period of time. In order to avoid that the UE continues to listen, in the embodiment of the present application, if the UE does not listen to the broadcast message including the identifier of the satellite 1 for more than a preset number of times, the anchor relationship between the UE and the satellite 1 can be canceled, which means that the satellite 1 is not used as the anchor satellite of the UE, and the UE can establish an anchor relationship with other satellites, which will be described in steps 1106-1112.

[0255] 1103, the eNB1 sends a second request message to the MME.

[0256] When the eNB1 determines that the anchor relationship between the UE and the satellite 1 needs to be canceled, the eNB1 sends a second request message to the MME, and the second request message is used to request to cancel the anchor relationship between the UE and the satellite 1. The eNB1 is deployed on the satellite 1.

[0257] For example, when the eNB1 detects that the number of UEs establishing an anchor relationship with the satellite 1 exceeds a threshold value, the anchor relationship between a part of the UEs and the satellite 1 can be canceled.

[0258] 1104, the MME sends a second response message to the eNB1.

[0259] If the MME allows to cancel the anchor relationship between the UE and the satellite 1, the MME can send a second response message to the eNB1, and the second response message indicates that the anchor relationship between the UE and the satellite 1 is allowed to be canceled.

[0260] 1105, the eNB1 sends second indication information to the UE.

[0261] The second indication information indicates to cancel the anchor relationship between the UE and the satellite 1, and the second indication information indicating to cancel the anchor relationship between the UE and the satellite 1 can be understood as that the second indication information indicates that the satellite 1 is no longer the anchor satellite of the UE.

[0262] The second indication information can be carried in the RRC connection release message or the RRC connection rejection message. The UE can establish the anchor relationship with the other satellite, which will be described in steps 1106-1112.

[0263] 1106, the eNB 2 sends a broadcast message, and the broadcast message includes the identity of the satellite 2. Correspondingly, the UE receives the broadcast message.

[0264] The broadcast message can be a system broadcast message, and the broadcast message includes the identity of the satellite 2 where the eNB 2 is located, that is, the eNB 2 is deployed on the satellite 2.

[0265] 1107, the RRC connection between the terminal device and the eNB 2 is established.

[0266] The terminal device can camp on the eNB 2 and establish the RRC connection with the eNB 2.

[0267] 1108, the eNB 2 sends a third request message to the MME, and the third request message requests to establish the anchor relationship between the UE and the satellite 2.

[0268] The third request message can include the identity of the UE and the identity of the satellite 2. Exemplarily, the third request message can be an anchor relationship establishment request message.

[0269] 1109, the MME stores the anchor relationship between the UE and the satellite 2.

[0270] Specifically, the MME storing the anchor relationship between the UE and the satellite 2 can be understood as that the MME can store the mapping relationship between the identity of the UE and the identity of the satellite 2.

[0271] In some implementations, the MME can update the stored anchor relationship between the UE and the satellite 1, for example, update the anchor relationship between the UE and the satellite 1 to the anchor relationship between the UE and the satellite 2. Specifically, the mapping relationship between the identity of the UE and the identity of the satellite 1 can be updated to the mapping relationship between the identity of the UE and the identity of the satellite 2.

[0272] In some implementations, if the UE initiatively cancels the anchor relationship between the UE and the satellite 1, the MME can send indication information to the eNB 1 deployed on the satellite 1, and the indication information indicates that the anchor relationship between the UE and the satellite 1 is canceled, or the indication information indicates that the anchor relationship between the UE and the satellite 2 is established.

[0273] 1110, the MME sends a third response message to the eNB 2, and the third response message indicates that the anchor relationship between the UE and the satellite 2 is allowed to be established.

[0274] The third response message can also be understood as a confirmation message, that is, confirming the anchor relationship between the UE and the satellite 2, and the third response message can be an anchor relationship establishment confirmation message.

[0275] 1111, the eNB 2 sends an RRC connection release message to the UE.

[0276] The RRC connection release message can comprise third indication information, the third indication information being used to indicate that the eNB 2 is the anchor satellite of the UE, that is, the satellite 2 where the eNB 2 is located is the anchor satellite of the UE.

[0277] Correspondingly, the UE can update the stored anchor relationship between the UE and the satellite 1 to the anchor relationship between the UE and the satellite 2, for example, update the stored identifier of the satellite 1 to the identifier of the satellite 2.

[0278] 1112, the UE determines the satellite 2 as the anchor satellite and stores the identifier of the satellite 2.

[0279] The cell covered by the satellite 2 can be referred to as an anchor satellite cell, and the UE can also store the identifier of the anchor satellite cell, that is, the identifier of the cell covered by the satellite 2, so as to determine whether the broadcast message is sent by the anchor satellite in subsequent search of the broadcast message. For example, if the identifier of the cell included in the searched broadcast message matches the identifier of the cell covered by the satellite 2 stored by the UE, it is determined that the broadcast message is sent by the anchor satellite.

[0280] The communication device provided by the embodiment of the present application will be introduced below.

[0281] The present application divides the function modules of the communication device according to the above-mentioned method embodiments, for example, each function module can be divided according to each function, or two or more functions can be integrated in one processing module. The integrated module can be realized in the form of hardware or in the form of software function module. It should be noted that the division of the modules in the present application is illustrative, and is only a logical function division, and another division mode can be used in actual implementation. The communication device of the embodiment of the present application will be described in detail below with reference to FIGS. 12 to 14.

[0282] FIG. 12 is a structural schematic diagram of a communication device provided by the embodiment of the present application, as shown in FIG. 12, the communication device 1000 can correspond to the functions or steps realized by the terminal device, the access network device or the core network device in each of the above-mentioned method embodiments.

[0283] In some possible implementation, the communication apparatus 1000 can correspond to implement the behavior and functions of the terminal device in the above method embodiments. For example, the communication apparatus 1000 can be the terminal device, or can be a component (for example, a chip or a circuit) applied to the terminal device. The transceiver unit 1100 can be used to perform all receiving or transmitting operations performed by the terminal device in the above method embodiments. The processing unit 1200 is used to perform all operations performed by the terminal device except the transceiver operations.

[0284] In a possible design, the communication apparatus 1000 includes: a transceiver unit 1100 and a processing unit 1200.

[0285] The processing unit 1200 is configured to determine that a first satellite is an anchor satellite of the terminal device, and a first access network device is deployed on the first satellite.

[0286] The transceiver unit 1100 is configured to receive downlink information from the first access network device, and / or transmit uplink information to the first access network device.

[0287] For example, the transceiver unit 1100 is specifically configured to establish a radio resource control (RRC) connection with the first access network device.

[0288] The transceiver unit 1100 is configured to receive downlink information from the first access network device based on the RRC connection, and / or transmit uplink information to the first access network device based on the RRC connection.

[0289] For example, the transceiver unit 1100 is specifically configured to establish an RRC connection with the first access network device in a case that the terminal device is located in a coverage range of the first satellite, and a broadcast message from the first access network device is received, where the broadcast message includes an identifier of the first satellite.

[0290] For example, the processing unit 1200 is specifically configured to receive first indication information by using the transceiver unit 1100, where the first indication information indicates to establish an anchor relationship between the first satellite and the terminal device; and determine that the first satellite is the anchor satellite of the terminal device according to the first indication information.

[0291] For example, the processing unit 1200 is further configured to determine that a second satellite is the anchor satellite of the terminal device in a case that the terminal device is located in the coverage range of the first satellite, and a broadcast message from the first access network device is not received in a preset number of times of listening.

[0292] For example, the transceiver unit 1100 is further configured to receive second indication information sent by the first access network device, where the second indication information indicates that the first satellite is no longer the anchor satellite of the terminal device.

[0293] The processing unit 1200 is configured to determine, according to the second indication information, that the second satellite is an anchor satellite of the terminal device.

[0294] For example, the processing unit 1200 is specifically configured to establish an RRC connection with a second access network device, where the second access network device is deployed on the second satellite.

[0295] The transceiver unit 1100 is further configured to receive third indication information from the second access network device, where the third indication information indicates that the anchor relationship between the second satellite and the terminal device is established.

[0296] The processing unit 1200 is configured to determine, according to the third indication information, that the second satellite is an anchor satellite of the terminal device.

[0297] The specific description and beneficial effects of the apparatus embodiment shown in FIG. 12 can refer to the description of the foregoing method embodiments, which will not be repeated here.

[0298] Referring to FIG. 12, the communication apparatus 1000 can correspond to the behavior and functions of the core network device in the foregoing method embodiments. For example, the communication apparatus 1000 can be a core network device, or a component (such as a chip or a circuit) applied to the core network device. The transceiver unit 1100 can be used to perform all receiving or transmitting operations performed by the core network device in the foregoing method embodiments. The processing unit 1200 is configured to perform all operations performed by the core network device except the transceiving operations.

[0299] In a possible design, the transceiver unit 1100 is configured to receive downlink information, where the downlink information is downlink information sent to a terminal device.

[0300] The processing unit 1200 is configured to determine that an anchor satellite of the terminal device is a first satellite, and that a first access network device is deployed on the first satellite.

[0301] The transceiver unit 1100 is further configured to send the downlink information to the first access network device.

[0302] For example, the transceiver unit 1100 is further configured to receive a first request message from the first access network device, where the first request message is used to request to establish an anchor relationship between the first satellite and the terminal device.

[0303] The transceiver unit 1100 is further configured to send a first response message to the first access network device, where the first response message indicates that the anchor relationship between the first satellite and the terminal device is allowed to be established.

[0304] The transceiver 1100 is further configured to receive a second request message from the first access network device, the second request message being used to request that the first satellite is no longer an anchor satellite for the terminal device.

[0305] The transceiver 1100 is further configured to send a second response message to the first access network device, the second response message indicating that the first satellite is allowed to be no longer an anchor satellite for the terminal device.

[0306] The specific description of the apparatus embodiment shown in FIG. 12 and the beneficial effects can refer to the description of the foregoing method embodiments, which will not be described here again.

[0307] Referring to FIG. 12, the communication apparatus 1000 can correspond to implement the behaviors and functions of the access network device in the foregoing method embodiments. For example, the communication apparatus 1000 can be an access network device, or can be a component (for example, a chip or a circuit) applied to an access network device. The transceiver 1100 can be configured to perform all receiving or sending operations performed by the access network device in the foregoing method embodiments. The processing unit 1200 is configured to perform all operations performed by the access network device except the transceiving operations.

[0308] In a possible design, the processing unit 1200 is configured to send first indication information to the terminal device through the transceiver 1100, the first indication information indicating to establish an anchor relationship between the first satellite and the terminal device.

[0309] After the anchor relationship between the first satellite and the terminal device is established, the anchor satellite of the terminal device is the first satellite.

[0310] The transceiver 1100 is further configured to send a first request message to the core network device, the first request message being used to request to establish an anchor relationship between the first satellite and the terminal device.

[0311] The transceiver 1100 is further configured to receive a first response message from the core network device, the first response message indicating that the anchor relationship between the first satellite and the terminal device is allowed to be established.

[0312] The transceiver 1100 is further configured to send a second request message to the core network device, the second request message being used to request that the first satellite is no longer an anchor satellite for the terminal device.

[0313] The transceiver 1100 is further configured to receive a second response message from the core network device, the second response message indicating that the first satellite is allowed to be no longer an anchor satellite for the terminal device.

[0314] For example, the transceiver unit 1100 is further configured to send second indication information to the terminal device, where the second indication information indicates that the first satellite is no longer an anchor satellite for the terminal device.

[0315] The terminal device, the access network device and the core network device are introduced above, and possible product forms of the terminal device, the access network device and the core network device are introduced below. It should be understood that any form of product that has the functions of the terminal device described in FIG. 12, or any form of product that has the functions of the access network device described in FIG. 12, or any form of product that has the functions of the core network device described in FIG. 12 falls within the protection scope of the embodiments of the present application. It should also be understood that the following introduction is only an example, and the product form of the terminal device, the access network device and the core network device of the embodiments of the present application is not limited to this.

[0316] In a possible implementation, in the communication apparatus shown in FIG. 12, the processing unit 1200 can be one or more processors, and the transceiver unit 1100 can be a transceiver, or the transceiver unit 1100 can also be a sending unit and a receiving unit, the sending unit can be a transmitter, and the receiving unit can be a receiver, and the sending unit and the receiving unit are integrated in one device, for example, a transceiver. In the embodiments of the present application, the processor and the transceiver can be coupled, and the connection mode of the processor and the transceiver is not limited in the embodiments of the present application.

[0317] FIG. 13 is a structural schematic diagram of another communication apparatus 2000 provided by the embodiments of the present application. The communication apparatus in FIG. 13 can be the terminal device, the access network device or the core network device.

[0318] As shown in FIG. 13, the communication apparatus 2000 includes one or more processors 2200 and a transceiver 2100. The transceiver 2100 can implement the functions of the transceiver unit 1100, and the processor 2200 can implement the functions of the processing unit 1200.

[0319] In each implementation of the communication apparatus shown in FIG. 13, the transceiver can include a receiver and a transmitter, the receiver is configured to perform the functions (or operations) of receiving, and the transmitter is configured to perform the functions (or operations) of transmitting. And the transceiver is configured to communicate with other devices / apparatuses through a transmission medium.

[0320] Optionally, the communication device 2000 can further include one or more memories 2300 for storing program instructions and / or data. The memory 2300 is coupled to the processor 2200. The coupling between the memory 2300 and the processor 2200 in the embodiments of the present application is indirect coupling or communication connection between devices, units or modules, which can be electrical, mechanical or other forms, for information interaction between devices, units or modules. The processor 2200 can operate in cooperation with the memory 2300. The processor 2200 can execute program instructions stored in the memory 2300.

[0321] The specific connection medium between the transceiver 2100, the processor 2200 and the memory 2300 in the embodiments of the present application is not limited. In FIG. 13, the transceiver 2100, the processor 2200 and the memory 2300 are connected by a bus 2400, which is represented by a thick line in FIG. 13. The connection mode between other components is only schematically illustrated and is not limited. The bus can be divided into an address bus, a data bus, a control bus, etc. For convenience of representation, only one thick line is used in FIG. 13, but it does not mean that there is only one bus or only one type of bus.

[0322] In the embodiments of the present application, the processor can be a general processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, etc., which can implement or execute the disclosed methods, steps and logic block diagrams in the embodiments of the present application. The general processor can be a microprocessor or any conventional processor, etc. The steps of the method disclosed in conjunction with the embodiments of the present application can be directly embodied as execution completed by a hardware processor, or executed by a combination of hardware and software modules in the processor, etc.

[0323] In the embodiments of the present application, the memory can include but is not limited to a non-volatile memory such as a hard disk drive (HDD) or a solid-state drive (SSD), a random access memory (RAM), an erasable programmable ROM (EPROM), a read-only memory (ROM) or a compact disc read-only memory (CD-ROM), etc. The memory is any storage medium capable of carrying or storing program codes in the form of instructions or data structures and capable of being read and / or written by a computer (such as the communication device shown in the present application), but is not limited thereto. The memory in the embodiments of the present application can also be a circuit or any other device capable of realizing a storage function, for storing program instructions and / or data.

[0324] The processor 2200 is mainly used for processing communication protocol and communication data, and controlling the whole communication device, executing software program and processing data of the software program. The memory 2300 is mainly used for storing software program and data. The transceiver 2100 can include control circuit and antenna, the control circuit is mainly used for converting baseband signal and radio frequency signal and processing radio frequency signal. The antenna is mainly used for receiving and sending radio frequency signal in the form of electromagnetic wave. Input and output device, such as touch screen, display screen, keyboard and the like, is mainly used for receiving user input data and outputting data to user.

[0325] When the communication device is powered on, the processor 2200 can read the software program in the memory 2300, interpret and execute the instruction of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor 2200 performs baseband processing on the data to be sent, and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit converts the baseband signal into radio frequency signal, and sends the radio frequency signal in the form of electromagnetic wave through the antenna. When data is sent to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into baseband signal, and outputs the baseband signal to the processor 2200. The processor 2200 converts the baseband signal into data and processes the data.

[0326] In another implementation, the radio frequency circuit and the antenna can be arranged independently of the processor for baseband processing, for example, in a distributed scenario, the radio frequency circuit and the antenna can be arranged remotely from the communication device.

[0327] It can be understood that the communication device shown in the embodiments of the present application can also have more components than those shown in FIG. 13, and the embodiments of the present application do not limit this. The method performed by the processor and the transceiver shown above is only an example, and the specific steps performed by the processor and the transceiver can refer to the method introduced above.

[0328] In another possible implementation, in the communication apparatus shown in FIG. 12, the processing unit 1200 can be one or more logic circuits, and the transceiver unit 1100 can be an input / output interface, also referred to as a communication interface, or an interface circuit, or an interface, etc. Alternatively, the transceiver unit 1100 can also be a sending unit and a receiving unit, the sending unit can be an output interface, and the receiving unit can be an input interface, and the sending unit and the receiving unit are integrated in one unit, for example, an input / output interface. As shown in FIG. 14, the communication apparatus shown in FIG. 14 includes a logic circuit 3001 and an interface 3002. That is, the processing unit 1200 can be implemented by the logic circuit 3001, and the transceiver unit 1100 can be implemented by the interface 3002. The logic circuit 3001 can be a chip, a processing circuit, an integrated circuit, or a system on chip (SoC) chip, etc., and the interface 3002 can be a communication interface, an input / output interface, a pin, etc. For example, FIG. 13 is a chip including the logic circuit 3001 and the interface 3002, taking the communication apparatus as the chip.

[0329] In the embodiments of the present application, the logic circuit and the interface can also be coupled to each other. The specific connection mode of the logic circuit and the interface is not limited in the embodiments of the present application.

[0330] It can be understood that the communication apparatus shown in the embodiments of the present application can implement the method provided by the embodiments of the present application in the form of hardware, or implement the method provided by the embodiments of the present application in the form of software, etc., and the embodiments of the present application do not limit this.

[0331] The embodiments of the present application further provide a wireless communication system, which includes an access network device and a terminal device, and the network device and the terminal device can be used to execute the method in any of the foregoing embodiments. Further optionally, the communication system can further include a core network device.

[0332] In addition, the present application further provides a computer-readable storage medium, which stores computer code, and when the computer code runs on a computer, the computer code causes the computer to execute the operations and / or processes performed by the terminal device, the access network device, or the core network device in the method provided by the present application.

[0333] The present application further provides a computer program product, which includes computer code or a computer program, and when the computer code or the computer program runs on a computer, the operations and / or processes performed by the terminal device, the access network device, or the core network device in the method provided by the present application are executed.

[0334] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other manners. For example, the described device embodiments are merely schematic. The division of the units is merely logical function division. There can be other division manners in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be electric, mechanical or in other forms.

[0335] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the technical effects of the solutions provided in the embodiments of the present application.

[0336] In addition, each functional unit in the various embodiments of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0337] The integrated unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the parts that make contributions, or all or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a computer readable storage medium, and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned computer readable storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0338] The above description is merely specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

A communication method applied to a terminal device, characterized in that, The method comprises: determining a first satellite as an anchor satellite of the terminal device, the first satellite being deployed with a first access network device, the anchor satellite being a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link; receiving downlink information from the first access network device, and / or sending uplink information to the first access network device. The method of claim 1, wherein The receiving downlink information from the first access network device, and / or sending uplink information to the first access network device comprises: establishing a radio resource control (RRC) connection with the first access network device; receiving downlink information from the first access network device based on the RRC connection, and / or sending uplink information to the first access network device based on the RRC connection. The method of claim 2, wherein The establishing a radio resource control (RRC) connection with the first access network device comprises: in a case where the terminal device is located in a coverage range of the first satellite and a broadcast message from the first access network device is received, establishing an RRC connection with the first access network device, the broadcast message comprising an identifier of the first satellite. The method of claim 1, wherein The determining a first satellite as an anchor satellite of the terminal device comprises: receiving first indication information sent by the first access network device, the first indication information indicating establishment of an anchor relationship between the first satellite and the terminal device; determining, according to the first indication information, the first satellite as the anchor satellite of the terminal device. The method of claim 3, wherein The method further comprises: in a case where the terminal device is located in a coverage range of the first satellite and a broadcast message from the first access network device is not received after listening for a preset number of times, determining a second satellite as the anchor satellite of the terminal device. The method of claim 1, wherein The method further comprises: receiving second indication information sent by the first access network device, the second indication information indicating that the first satellite is no longer the anchor satellite of the terminal device; determining, according to the second indication information, a second satellite as the anchor satellite of the terminal device. The method as claimed in claim 5 or 6, characterized in that The determining a second satellite as the anchor satellite of the terminal device comprises: establishing an RRC connection with a second access network device, the second access network device being deployed on the second satellite; receiving third indication information from the second access network device, the third indication information indicating establishment of an anchor relationship between the second satellite and the terminal device; determining, according to the third indication information, the second satellite as the anchor satellite of the terminal device. A communication method characterized by comprising: The method comprises: receiving downlink information, the downlink information being downlink information sent to a terminal device; determining a first satellite as an anchor satellite of the terminal device, the first satellite being deployed with a first access network device, the anchor satellite being a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link; sending the downlink information to the first access network device. The method of claim 8, wherein The method further comprises: receiving a first request message from the first access network device, the first request message being used to request establishment of an anchor relationship between the first satellite and the terminal device; sending a first response message to the first access network device, the first response message indicating that the first satellite and the terminal device are allowed to establish the anchor relationship. The method of claim 8, wherein The method further includes: receiving a second request message from the first access network device, the second request message being used to request that the first satellite is no longer an anchor satellite for the terminal device; sending a second response message to the first access network device, the second response message indicating that the first satellite is allowed to be no longer an anchor satellite for the terminal device. A communication method characterized by comprising: The method is applied to an access network device, which is deployed in a first satellite, and the method includes: sending first indication information to a terminal device, the first indication information indicating that an anchor relationship between the first satellite and the terminal device is to be established; after the anchor relationship between the first satellite and the terminal device is established, an anchor satellite for the terminal device is the first satellite, and the anchor satellite is a satellite that establishes a service link with the terminal device and communicates with the terminal device based on the service link. The method of claim 11, wherein Before the first indication information is sent to the terminal device, the method further includes: sending a first request message to a core network device, the first request message being used to request that the anchor relationship between the first satellite and the terminal device is to be established; receiving a first response message from the core network device, the first response message indicating that the anchor relationship between the first satellite and the terminal device is allowed to be established. The method of claim 11, wherein After the first indication information is sent to the terminal device, the method further includes: sending a second request message to a core network device, the second request message being used to request that the first satellite is no longer an anchor satellite for the terminal device; receiving a second response message from the core network device, the second response message indicating that the first satellite is allowed to be no longer an anchor satellite for the terminal device. The method of claim 13, wherein The method further includes: sending second indication information to the terminal device, the second indication information indicating that the first satellite is no longer an anchor satellite for the terminal device. A communication device, characterized by The apparatus includes units for performing the method of any one of claims 1-7, or units for performing the method of any one of claims 8-10, or units for performing the method of any one of claims 11-14. A communication device, characterized by The apparatus includes a processor configured to perform the method of any one of claims 1-7, or the method of any one of claims 8-10, or the method of any one of claims 11-14. A computer storage medium, characterized by The computer storage medium is configured to store a computer program, which, when executed, performs the method of any one of claims 1-7, or the method of any one of claims 8-10, or the method of any one of claims 11-14.

Images