Communication method, communication apparatus and communication system

Abstract

A communication method, a communication apparatus and a communication system, which are applied to the technical field of communications. The method comprises: a first satellite sending a first broadcast message, and correspondingly, a terminal apparatus receiving the first broadcast message, wherein the first broadcast message comprises first indication information, and the first indication information indicates ephemeris information of a second satellite; and the terminal apparatus receiving a second broadcast message from the second satellite on the basis of the first indication information. The embodiments of the present application can reduce the time for a terminal apparatus to capture a satellite.

Description

Communication method, communication device and communication system

[0001] This application claims priority to the Chinese patent application with application number 202410054547.3 filed with the State Intellectual Property Office of China on January 15, 2024, and priority to the Chinese patent application with the invention name “Communication Method, Communication Device and Communication System”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a communication method, a communication device, and a communication system. Background Art

[0003] In a non-terrestrial network (NTN) system, satellites can send synchronization signal blocks (SSBs) using beam scanning. Terminal devices need to scan the SSBs sent by satellites at multiple frequencies and in multiple beam directions to access the satellite. For a single frequency, the terminal device needs to scan the SSBs sent by the satellite in each beam direction. The time required for the terminal device to search for a single frequency is determined by the SSB scanning period and the number of beams required for the terminal device to complete the scan. If the terminal device needs to scan multiple frequency information, the time it takes for the terminal device to capture the satellite is proportional to the number of frequencies scanned.

[0004] However, in the above-mentioned method for a terminal device to access a satellite, it takes a long time for the terminal device to capture the satellite. Summary of the Invention

[0005] The embodiments of the present application provide a communication method, a communication device, and a communication system, which can reduce the time it takes for a terminal device to capture a satellite.

[0006] In a first aspect, an embodiment of the present application provides a communication method, which is applied to a terminal device. It is understood that the terminal device may include a terminal device or a chip (system) or circuit for a terminal device, and this application does not limit this. The method includes:

[0007] A first broadcast message from a first satellite is received, where the first broadcast message includes first indication information, where the first indication information indicates ephemeris information of a second satellite; and a second broadcast message from the second satellite is received based on the first indication information.

[0008] In an embodiment of the present application, the coverage range of the first satellite is greater than the coverage range of the second satellite. Alternatively, the orbital altitude of the first satellite is higher than the orbital altitude of the second satellite. The first satellite may also be referred to as a high-level satellite, and the second satellite may also be referred to as a low-level satellite. The second satellite may be located within the coverage range of the first satellite. The first satellite may broadcast the ephemeris information of the second satellite so that the terminal device can obtain the ephemeris information of the second satellite and adjust the receiving beam direction according to the ephemeris information of the second satellite so that the receiving beam points to the second satellite. The terminal device does not need to perform beam scanning, which can effectively reduce the time it takes for the terminal device to capture the satellite, allowing the terminal device to quickly access the second satellite.

[0009] In a second aspect, an embodiment of the present application provides a communication method, which is applied to a first satellite. It is understood that the method can be executed by the first satellite, or by a chip (system) or circuit used for the first satellite, and this application does not limit this. The method includes:

[0010] Acquire ephemeris information of a second satellite; and send a first broadcast message, where the first broadcast message includes first indication information, and the first indication information indicates the ephemeris information of the second satellite.

[0011] In conjunction with the second aspect, in a possible implementation, obtaining ephemeris information of the second satellite includes:

[0012] First information from the second satellite is received, where the first information includes ephemeris information of the second satellite.

[0013] In combination with the second aspect, in a possible implementation, the first information also includes at least one of the following: synchronization signal block SSB information of the second satellite, coverage of the second satellite, and load status of the second satellite.

[0014] In combination with the first aspect or the second aspect, in a possible implementation, the first broadcast message also includes at least one of the following: SSB information, second indication information or third indication information of the second satellite; wherein the second indication information is used to indicate the coverage range of the second satellite, and the third indication information is used to indicate the load condition of the second satellite.

[0015] In an embodiment of the present application, the first satellite also broadcasts the SSB information of the second satellite, so that the terminal device can obtain the SSB information of the second satellite (such as the center frequency or time domain information of the SSB, etc.), so that the SSB of the second satellite can be received at a fixed frequency without the need for frequency scanning, thereby reducing the time it takes for the terminal device to capture the second satellite. Alternatively, the first satellite also broadcasts the coverage range of the second satellite, so that the terminal device can determine whether it is within the coverage range of the second satellite, so that the terminal device can access the second satellite more quickly, greatly reducing the time it takes for the terminal device to capture the satellite. Alternatively, the first satellite also broadcasts the load condition of the second satellite, so that the terminal device can select a more suitable second satellite based on the load condition, ensure load balancing between satellites, avoid long subsequent access time caused by congestion, and ensure that the second satellite can provide better access services for the terminal device.

[0016] In combination with the first aspect or the second aspect, in a possible implementation manner, the second indication information indicates the longitude and latitude corresponding to the coverage range of the second satellite.

[0017] In an embodiment of the present application, the second indication information indicates the longitude and latitude corresponding to the coverage range of the second satellite, so that the terminal device can quickly determine the coverage range of the second satellite through the longitude and latitude.

[0018] In combination with the first aspect or the second aspect, in a possible implementation manner, the second indication information indicates an identifier of a geographical area corresponding to the coverage range of the second satellite.

[0019] In the embodiment of the present application, the global geographical area can be divided into multiple geographical areas, and the multiple geographical areas are numbered to obtain the identification of each geographical area. The identification of the geographical area corresponding to the coverage range of the second satellite can accurately indicate the coverage area of ​​the second satellite.

[0020] In combination with the first aspect or the second aspect, in a possible implementation manner, the second indication information indicates a range of values ​​of an angle between a beam emitted by the second satellite and a plane formed by an antenna panel of the second satellite.

[0021] In the embodiment of the present application, the beam transmitted by the second satellite can be received within the coverage range of the second satellite. Therefore, the coverage range of the second satellite can be indicated by the value range of the angle between the beam transmitted by the second satellite and the plane formed by the antenna panel of the second satellite. Based on the value range of the angle between the beam transmitted by the second satellite and the plane formed by the antenna panel of the second satellite, the terminal device can accurately determine the coverage range of the second satellite.

[0022] In combination with the first aspect or the second aspect, in a possible implementation manner, the third indication information includes the number of users currently connected to the second satellite and / or the ratio of the number of users currently connected to the second satellite to the number of users allowed to connect to the second satellite.

[0023] In the embodiment of the present application, the load condition of the second satellite can be intuitively reflected by the number of users currently connected to the second satellite or the ratio of the number of users currently connected to the second satellite to the number of users allowed to connect.

[0024] In combination with the first aspect or the second aspect, in one possible implementation, the SSB information includes at least one of the following information of the second satellite: SSB center frequency, sub-carrier space (SCS), system frame number (SFN) offset, SSB transmission period, SSB time domain information, and half-frame index.

[0025] In an embodiment of the present application, the SCS, SFN offset, SSB transmission period, SSB time domain information, half-frame index, etc. can be used to determine the time domain position of the SSB of the second satellite, so that the terminal device can only monitor the broadcast signal of the second satellite at the time domain position of the SSB of the second satellite (such as during the period when the second satellite transmits the SSB), and does not need to monitor at other times, which can save power consumption of the terminal device. The SSB information includes the SSB center frequency, so that the terminal device can receive the SSB of the second satellite at a fixed frequency without frequency scanning, thereby reducing the time it takes for the terminal device to capture the second satellite.

[0026] In combination with the first aspect or the second aspect, in a possible implementation manner, the first indication information includes ephemeris information of the first satellite and an offset of the ephemeris of the second satellite relative to the ephemeris of the first satellite.

[0027] In combination with the first aspect or the second aspect, in a possible implementation manner, the first broadcast message further includes fourth indication information, where the fourth indication information is used to indicate that the first broadcast message also includes access information of the first satellite.

[0028] In an embodiment of the present application, the first broadcast message also includes access information of the first satellite, so that the terminal device can access the first satellite. For example, when the terminal device fails to access the second satellite, the terminal device can access the first satellite based on the access information of the first satellite.

[0029] In combination with the first aspect or the second aspect, in a possible implementation, the first indication information indicates the ephemeris information of multiple satellites, and the second satellite is one of the multiple satellites whose distance to the terminal device is closer, or the second satellite is one of the multiple satellites whose distance to the terminal device is less than or equal to a distance threshold.

[0030] In an embodiment of the present application, a second satellite that meets the conditions is selected from the multiple satellites based on the distances between the multiple satellites and the terminal device, thereby ensuring that the second satellite provides better access service for the terminal device.

[0031] In combination with the first aspect or the second aspect, in a possible implementation, the first indication information indicates the ephemeris information of multiple satellites, and the second satellite is one of the multiple satellites with a longer service time, or the second satellite is one of the multiple satellites with a service time greater than or equal to a time threshold.

[0032] In an embodiment of the present application, the terminal device can select a second satellite whose service duration meets the requirements from the multiple satellites, thereby avoiding the terminal device from frequently switching service satellites, so that the second satellite can provide better access services for the terminal device.

[0033] In combination with the first aspect or the second aspect, in a possible implementation, the first indication information indicates the ephemeris information of multiple satellites, and the second satellite is one of the multiple satellites with higher signal quality, or the second satellite is one of the multiple satellites with a signal quality greater than or equal to a signal quality threshold.

[0034] In the embodiment of the present application, the terminal device can select a second satellite whose signal quality meets the requirements from multiple satellites, thereby ensuring the service quality when the second satellite provides access services to the terminal device.

[0035] In a third aspect, an embodiment of the present application provides a communication method, which is applied to a second satellite. It is understood that the method can be executed by the second satellite, or by a chip (system) or circuit used for the second satellite, and this application does not limit this. The method includes:

[0036] First information is sent to the first satellite, where the first information includes ephemeris information of the second satellite; and a second broadcast message is sent.

[0037] In an embodiment of the present application, the second satellite may send its ephemeris information to the first satellite, so that the first satellite can broadcast the ephemeris information of the second satellite.

[0038] In combination with the third aspect, in a possible implementation, the first information also includes at least one of the following: synchronization signal block SSB information of the second satellite, coverage of the second satellite, and load status of the second satellite.

[0039] In an embodiment of the present application, the second satellite also sends SSB information, the coverage range of the second satellite, or the load status of the second satellite to the first satellite, so that the first satellite can broadcast the SSB information, the coverage range of the second satellite, or the load status of the second satellite, assist the terminal device in capturing the second satellite, and shorten the time for the terminal device to capture the second satellite.

[0040] In a fourth aspect, an embodiment of the present application provides a communication device for executing the method in the first aspect or any possible implementation of the first aspect. The communication device includes a unit having a function of executing the method in the first aspect or any possible implementation of the first aspect.

[0041] In a fifth aspect, an embodiment of the present application provides a communication device for executing the method in the second aspect or any possible implementation of the second aspect. The communication device includes a unit having the function of executing the method in the second aspect or any possible implementation of the second aspect.

[0042] In a sixth aspect, an embodiment of the present application provides a communication device for executing the method in the third aspect or any possible implementation of the third aspect. The communication device includes a unit having the function of executing the method in the third aspect or any possible implementation of the third aspect.

[0043] In the fourth aspect, the fifth aspect, or the sixth aspect, the communication device and the communication device may include a transceiver unit and a processing unit. For a detailed description of the transceiver unit and the processing unit, reference may be made to the device embodiments shown below.

[0044] In a seventh aspect, an embodiment of the present application provides a communication device, comprising a processor configured to execute the method described in any one of the first to third aspects or any possible implementation thereof. Alternatively, the processor is configured to execute a program stored in a memory, and when the program is executed, the method described in any one of the first to third aspects or any possible implementation thereof is executed.

[0045] In a possible implementation, the memory is located outside the communication device.

[0046] In a possible implementation, the memory is located within the above-mentioned communication device.

[0047] In an embodiment of the present application, the processor and the memory may also be integrated into one device, that is, the processor and the memory may also be integrated together.

[0048] In a possible implementation, the communication device further includes a transceiver, where the transceiver is configured to receive a signal or send a signal.

[0049] In an eighth aspect, an embodiment of the present application provides a communication device, which includes a logic circuit and an interface, wherein the logic circuit and the interface are coupled; the interface is used to input a first broadcast message; and the logic circuit is used to input a second broadcast message through the interface based on the first indication information.

[0050] It can be understood that with respect to the communication device shown in the eighth aspect, reference can also be made to the first aspect or the specific implementation shown below.

[0051] In a ninth aspect, an embodiment of the present application provides a communication device, which includes a logic circuit and an interface, wherein the logic circuit and the interface are coupled; the logic circuit is used to obtain the ephemeris information of the second satellite; and the interface is used to output a first broadcast message.

[0052] It can be understood that with respect to the communication device shown in the ninth aspect, reference can also be made to the second aspect or the specific implementation shown below.

[0053] In a tenth aspect, an embodiment of the present application provides a communication device, which includes a logic circuit and an interface, wherein the logic circuit and the interface are coupled; the interface is used to output a first information and a second broadcast message.

[0054] It can be understood that with respect to the communication device shown in the tenth aspect, reference can also be made to the third aspect or the specific implementation shown below.

[0055] In the eleventh aspect, an embodiment of the present application provides a computer-readable storage medium, which is used to store a computer program. When the computer program is run on a computer, the method shown in any one of the first to third aspects or any possible implementation method is executed.

[0056] In the twelfth aspect, an embodiment of the present application provides a computer program product, which includes a computer program. When the computer program is run on a computer, the method shown in any aspect of the first to third aspects or any possible implementation method is executed.

[0057] In a thirteenth aspect, an embodiment of the present application provides a computer program. When the computer program is run on a computer, the method shown in any one of the first to third aspects or any possible implementation is executed.

[0058] In the fourteenth aspect, an embodiment of the present application provides a communication system, which includes at least two of the following: a terminal device, a first satellite, and a second satellite, wherein the terminal device is used to execute the method shown in the above-mentioned first aspect or any possible implementation of the first aspect, the first satellite is used to execute the method shown in the above-mentioned second aspect or any possible implementation of the second aspect, and the second satellite is used to execute the method shown in the above-mentioned third aspect or any possible implementation of the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The following is an introduction to the drawings related to the embodiments of this application.

[0060] FIG1A is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0061] FIG1B is a schematic diagram of the architecture of another communication system provided in an embodiment of the present application;

[0062] FIG1C is a schematic diagram of the architecture of another communication system provided in an embodiment of the present application;

[0063] FIG2 is a schematic diagram of a beam scanning method provided in an embodiment of the present application;

[0064] FIG3 is a flow chart of a communication method provided in an embodiment of the present application;

[0065] FIG4 is a flow chart of another communication method provided in an embodiment of the present application;

[0066] FIG5 is a flow chart of another communication method provided in an embodiment of the present application;

[0067] FIG6 is a schematic diagram of a coverage range of a second satellite provided in an embodiment of the present application;

[0068] FIG7 is a flow chart of another communication method provided in an embodiment of the present application;

[0069] FIG8 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0070] FIG9 is a schematic structural diagram of another communication device provided in an embodiment of the present application;

[0071] FIG10 is a schematic structural diagram of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0072] The terms "first" and "second" in the specification, claims and drawings of this application are only used to distinguish different objects, and are not used to limit the order, timing, priority or importance of multiple objects. In the embodiments of the present application, "multiple" refers to two or more. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. In addition, the character " / ", unless otherwise specified, generally indicates that the objects associated before and after are in an "or" relationship.

[0073] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It will be understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0074] With the development of information technology, modern communication systems have put forward more urgent requirements for communication efficiency, mobility, and diversity. At present, in some important application scenarios such as space communication, aviation communication, maritime communication, and military communication, non-terrestrial network (NTN) communication represented by non-ground equipment such as satellites, drones, and high-altitude platforms plays an irreplaceable role.

[0075] For the sake of convenience, the following description will be made using non-terrestrial equipment represented by satellites as an example.

[0076] Satellite communications offer long communication distances, wide coverage, and flexible networking. They can provide communication services for both fixed and mobile terminals. Because traditional terrestrial networks cannot provide seamless coverage for terminal devices, especially in locations where base stations cannot be deployed, such as the ocean, deserts, and the air, NTN has been introduced into the fifth-generation (5G) mobile communications system. This system deploys base stations, or some base station functions, on high-altitude platforms or satellites, providing seamless coverage for terminal devices. Furthermore, high-altitude platforms or satellites are less susceptible to natural disasters, enhancing the reliability of 5G systems. In satellite-based NTNs, satellites cover the ground using different beams, forming satellite cells. A single terminal device can be covered by multiple satellite cells at the same time.

[0077] Satellite communication systems can be divided into the following three types according to the satellite's orbital altitude:

[0078] Geostationary earth orbit (GEO) satellite communication system, also known as synchronous orbit satellite system, medium earth orbit (MEO) satellite communication system and low earth orbit (LEO) satellite communication system.

[0079] GEO satellites orbit at an altitude of 35,786 km. Their main advantages are their ability to remain stationary relative to the Earth and provide a wide coverage area. However, their disadvantages are: 1) GEO satellites are located far from Earth, resulting in significant free-space propagation losses, which limits communication link budgets. To increase transmit / receive gain, satellites must be equipped with larger antennas. 2) Communication transmission latency is significant, reaching around 500ms round-trip, which cannot meet the needs of real-time services. 3) GEO orbital resources are relatively limited, launch costs are high, and coverage of the Earth's polar regions is limited.

[0080] MEO satellites orbit at altitudes between 2,000 and 35,786 km. Their advantage is that they can achieve global coverage with a relatively small number of satellites. However, their orbital altitude is higher than that of LEO satellites, and transmission latency is still greater than that of LEO satellite communications. Considering the advantages and disadvantages of MEO satellite communications, MEO satellites are primarily used for positioning and navigation.

[0081] LEO satellites orbit at altitudes between 300 and 2000 km. These satellites are lower than MEO and GEO orbits, offering advantages such as reduced data transmission latency, minimal transmission loss, and relatively low launch costs. To improve the overall signal processing capabilities and communication throughput of satellite networks, satellite operators are increasing the number of satellites to offset the communication capacity limitations of individual satellites. In future NTN communication systems, after a terminal device is connected to the system, it will be "visible" to multiple communicative satellites for a period of time. Multiple satellites can now provide communication services to the terminal device, laying the foundation for multi-satellite coordinated transmission.

[0082] The technical solutions provided in the embodiments of the present application can be applied to various communication systems, for example, satellite communication systems and systems integrating satellite communication and cellular networks. Among them, the cellular network system may include but is not limited to: 5G system, global system of mobile communication (GSM) system, code division multiple access (CDMA) system, wideband code division multiple access (WCDMA) system, general packet radio service (GPRS), long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD) system, advanced long term evolution (LTE-A) system, new radio (NR) system, NR system evolution system, LTE on unlicensed band (LTE-based access to unlicensed spectrum, LTE-U) system, NR on unlicensed band (NR-based access to unlicensed spectrum, NR-U) system, universal mobile telecommunication system (UMTS), world-wide interoperability for microwave access (WiMAX) communication system, wireless local area network (WLAN) system. area networks (WLAN), wireless fidelity (WiFi), next generation communication systems or other communication systems, etc.Generally speaking, traditional communication systems support a limited number of connections and are easy to implement. However, with the development of communication technology, mobile communication systems will not only support traditional communications, but will also support, for example: device to device (D2D) communication, machine to machine (M2M) communication, machine type communication (MTC), vehicle to vehicle (V2V) communication, and other communication systems that will evolve in the future. The embodiments of the present application can also be applied to these communication systems. Satellite communication systems can include various non-terrestrial network systems, such as satellites or unmanned aircraft systems (UAS) platforms, which transmit wireless frequencies, and are not listed here one by one.

[0083] For example, the following takes the NTN system as an example to provide a specific application scenario of this solution. The NTN system can be a satellite communication system or other non-terrestrial network system. The positioning method in this solution can be applied in the field of satellite communication.

[0084] Please refer to Figures 1A, 1B and 1C. Taking the 5G communication system as an example, Figures 1A, 1B and 1C are architectural diagrams of several communication systems provided in embodiments of the present application.

[0085] As shown in Figures 1A, 1B, and 1C, one or more terminal devices (e.g., mobile terminals) and / or network devices (e.g., 5G base stations) may exist within the coverage area of ​​a satellite cell. The coverage area of ​​the cell may be the area covered by one or more beams of the satellite, or an area at the same level as a cell in an NR system.

[0086] In Figure 1A, ground-based terminal devices (such as mobile terminals) access the network through the air interface. Network equipment (such as 5G base stations) can be deployed on the ground and directly connected to the terrestrial 5G core network and the satellite communication ground station via wireless links. This type of communication architecture is also called a transparent satellite network architecture. The base stations are visible on the ground. At the same time, wireless links exist between satellites to facilitate signaling exchange and user data transmission between base stations.

[0087] In Figure 1B, ground-based terminal devices (such as mobile terminals) access the network through the air interface. Network equipment (such as 5G base stations) can be deployed on satellites and connected to ground stations and the terrestrial 5G core network via wireless links. This type of communication architecture is also known as a regenerative satellite network architecture, where the base station or part of the base station's functions are located on the satellite. At the same time, wireless links exist between satellites, enabling signaling and user data transmission between base stations.

[0088] In Figure 1C, ground-based terminal devices (such as mobile terminals) access the network through the air interface. Network equipment (such as 5G base stations) or part of the network equipment (such as 5G base stations) is deployed on the satellite and connected to the ground station and the terrestrial 5G core network via wireless links. The functions of part of the network equipment (such as 5G base stations) are deployed on the ground and directly connected to the terrestrial 5G core network and the satellite communication ground station via wireless links. In this type of communication architecture, the functions of the base station or part of the base station are respectively on the satellite and on the ground. At the same time, there is a wireless link between the satellites to complete the signaling exchange and user data transmission between the base stations.

[0089] It is understandable that in actual deployment, the satellites in the above system can be replaced by other NTN devices such as high altitude platform stations (HAPS), and this application does not impose any restrictions on this.

[0090] The network elements and their interfaces in this scenario are described as follows:

[0091] Terminal device: A mobile device that supports the 5G new air interface, typically a user terminal, wearable device, or other mobile device. It can access the satellite network through the air interface and initiate calls, access the Internet, and other services.

[0092] 5G base station: mainly provides wireless access services, dispatches wireless resources to access terminals, and provides reliable wireless transmission protocols and data encryption protocols.

[0093] 5G Core Network: This includes services such as user access control, mobility management, session management, user security authentication, and billing. It consists of multiple functional units, which can be divided into control plane and data plane functional entities. The access and mobility management function (AMF) is responsible for user access management, security authentication, and mobility management. The location management function (LMF) is responsible for managing and controlling positioning service requests from target terminals and processing positioning-related information. The user plane function (UPF) is responsible for managing user plane data transmission, traffic statistics, and other functions.

[0094] Ground station: responsible for forwarding signaling and service data between satellite base stations and 5G core network.

[0095] 5G New Radio: The wireless link between user equipment and base stations.

[0096] Xn interface: It is the interface between 5G base stations and is mainly used for signaling interaction such as switching.

[0097] NG interface: It is the interface between the 5G base station and the 5G core network, mainly used for signaling such as the non-access stratum (NAS) of the core network and user service data.

[0098] The technical solution provided in this application mainly involves two execution entities: network equipment and terminal equipment, and can be applied to communication systems such as 5G, especially in the communication process of non-terrestrial networks.

[0099] The terminal devices involved in the embodiments of the present application include but are not limited to being connected via a wired line, such as via a public switched telephone network (PSTN), a digital subscriber line (DSL), a digital cable, a direct cable connection; and / or another data connection network; and / or via a wireless interface, such as: for a cellular network, a wireless local area network (WLAN), a digital television network such as a digital video broadcast-handheld (DVB-H) network, a satellite network, an amplitude modulation-frequency modulation (AM-FM) broadcast transmitter; and / or a device of another terminal device configured to receive / send communication signals; and / or an Internet of Things (IoT) device. A terminal device configured to communicate via a wireless interface may be referred to as a "wireless communication terminal", "wireless terminal" or "mobile terminal". Examples of such terminal devices include, but are not limited to, satellite or cellular telephones; personal communications system (PCS) terminals that may combine cellular radiotelephones with data processing, fax, and data communications capabilities; personal digital assistants (PDAs) that may include radiotelephones, pagers, Internet / Intranet access, web browsers, organizers, calendars, and / or global positioning system (GPS) receivers; and conventional laptop and / or palmtop receivers or other electronic devices that include radiotelephone transceivers. Terminal devices may also be referred to as user equipment (UE), access terminals, subscriber units, subscriber stations, mobile stations, mobile stations, remote stations, remote terminals, mobile devices, user terminals, terminals, wireless communication devices, user agents, or user devices. The terminal device may also be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a PDA, a handheld device with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in a 5G network, or a terminal device in a future evolved public land mobile network (PLMN), etc.

[0100] The network equipment involved in the embodiments of the present application can provide communication coverage in a specific geographical area, and can communicate with one or more terminal devices located in the coverage area, and can also be used to communicate with one or more base stations with partial terminal functions (such as communication between a macro base station and a micro base station, such as an access point). Optionally, the network device can be a base station (base transceiver station, BTS) in a satellite, GSM system or CDMA system, an evolved base station (evolved Node B, eNB) in an LTE system, or a next generation node base station (next generation node base station, gNB) in a 5G system or NR system, as well as other satellite base stations and satellite relay nodes. In addition, the network device can also be an access point (AP), a transport point (TRP), a central unit (CU) or other network entity, and can include some or all of the above network entity functions.

[0101] It is understood that a device having a communication function in a network / system in the embodiments of the present application may be referred to as a communication device. Taking the communication system shown in Figures 1A, 1B, and 1C as an example, the communication device may include a network device and a terminal device having a communication function. The network device and the terminal device may be the specific devices described above and will not be described in detail here. The communication device may also include other devices in the communication system, such as a network controller, a mobility management entity, and other network entities, which are not limited in the embodiments of the present application.

[0102] It should also be noted that in this application, the two descriptions of "satellite" and "satellite network equipment" are equivalent. That is, the satellite mentioned in this application refers to a collection of satellites and other network equipment related to satellite communications.

[0103] It can be understood that a cell in the NTN system can be the projection area of ​​a satellite beam on the ground, or the projection area of ​​multiple satellite beams on the ground, or it can be a partial area of ​​the projection area of ​​one beam or multiple beams on the ground. The embodiments of the present application are not limited to this.

[0104] In the NTN system, satellites can transmit synchronization signal blocks (SSBs) using beam scanning. To align with the satellite, the terminal device needs to perform frequency and beam scanning. The terminal device needs to scan the SSBs transmitted by the satellite across multiple frequencies and multiple beam directions. For a single frequency, the terminal device needs to scan the SSBs transmitted by the satellite in each beam direction. The time required for the terminal device to search for a single frequency is determined by the SSB scanning period and the number of beams required to complete the scan. If the terminal device needs to scan multiple frequencies, the time it takes to acquire a satellite is proportional to the number of frequencies scanned. For example, as shown in Figure 2, the terminal device does not have built-in satellite ephemeris information. The antenna specifications of the terminal device are a 32*32 antenna array, the 3dB beamwidth of the terminal device is 3.2 degrees, the maximum scanning angle of the terminal device is 60 degrees, the number of beams required to complete the scan is approximately 2614, and the SSB scanning period is 20ms. Therefore, the time required for the terminal device to search for a single frequency point is 2614 * 20ms = 52.28s, which is a long time. This is especially true for devices in edge-of-band locations. Because the terminal device takes a long time to acquire a satellite, the satellite may have already flown away while the terminal device is aligning its beam, leaving it out of reach. This forces the terminal device to re-scan the frequency and beam to acquire the next satellite, thus increasing the time it takes for the terminal device to acquire a satellite.

[0105] In view of this, an embodiment of the present application provides a communication method that can effectively shorten the time it takes for a terminal device to capture a satellite. The method provided in the embodiment of the present application can be applied to the system shown in Figure 1A, Figure 1B, or Figure 1C.

[0106] It is understandable that although the method shown below does not involve a relay node, those skilled in the art will know that when a sender and a receiver communicate, a forwarding operation can be performed through a relay node.

[0107] It is understood that the interaction diagrams in this application use network devices and terminal devices as examples of the execution entities of the interaction diagrams to illustrate the method, but this application does not limit the execution entities of the interaction diagrams. For example, the network device in the interaction diagram can also be a chip, chip system, or processor that supports the network device to implement the method, or a logical node, logic module, or software that can implement all or part of the network device functions; the terminal device in the interaction diagram can also be a chip, chip system, or processor that supports the terminal to implement the method.

[0108] Please refer to Figure 3, which is a flow chart of a communication method provided in an embodiment of the present application. As shown in Figure 3, the method includes but is not limited to the following steps.

[0109] Optionally, the method shown in FIG3 may include step 301 .

[0110] 301. A second satellite sends first information. Correspondingly, a first satellite receives the first information, where the first information includes ephemeris information of the second satellite.

[0111] 302: A first satellite sends a first broadcast message, and correspondingly, a terminal device receives the first broadcast message. The first broadcast message includes first indication information, and the first indication information indicates ephemeris information of a second satellite.

[0112] For example, the coverage area of ​​the first satellite is greater than the coverage area of ​​the second satellite. Alternatively, the orbital altitude of the first satellite is higher than the orbital altitude of the second satellite. The first satellite may also be referred to as a high-layer satellite, and the second satellite may also be referred to as a low-layer satellite. For example, the first satellite may be a GEO satellite, and the second satellite may be a LEO satellite. The second satellite may be located within the coverage area of ​​the first satellite.

[0113] As an example, the first indication information includes ephemeris information of the second satellite.

[0114] As another example, the first indication information includes the ephemeris information of the first satellite and the offset of the ephemeris of the second satellite relative to the ephemeris of the first satellite. The terminal device can determine the ephemeris information of the second satellite based on the first indication information. For example, if the ephemeris information of the first satellite includes parameters such as the coordinates, orientation, and speed of the first satellite, the first indication information may include the difference between the coordinates of the second satellite and the first satellite, the difference between the orientations of the second satellite and the first satellite, and the difference between the speeds of the second satellite and the first satellite.

[0115] Exemplarily, the first broadcast message may be a system information block (SIB) message sent by the first satellite. The first broadcast message may include access information of the first satellite or may not include access information of the first satellite.

[0116] As an example, the first broadcast message may be a newly defined SIB1 information element, such as IE SIB1-lightweigh. The first broadcast message may not include access information and SI scheduling information of the first satellite, but may include first indication information for indicating ephemeris information of the second satellite.

[0117] As another example, fourth indication information may be used to indicate whether the first broadcast message includes access information of the first satellite. For example, the first broadcast message includes fourth indication information, and the fourth indication information is used to indicate that the first broadcast message also includes access information of the first satellite. The first broadcast message may be a SIB1 message specified in the NR protocol. The fourth indication information may include a FLAG identifier (FlagAccessOther), and the value of the flag identifier indicates whether the first broadcast message includes access information of the first satellite. For example, when the flag identifier is 1, it indicates that the first broadcast message includes access information of the first satellite. When the flag identifier is 0, it indicates that the first broadcast message does not include access information of the first satellite.

[0118] It is understood that the value of the flag identifier is only an example and should not be understood as a limitation of the present application. In the embodiment of the present application, the value of the flag identifier can also be other values, and the present application does not limit it.

[0119] In one possible implementation, the first broadcast message also includes at least one of the following: SSB information of the second satellite, second indication information, or third indication information; wherein the second indication information is used to indicate the coverage range of the second satellite, and the third indication information is used to indicate the load condition of the second satellite.

[0120] Exemplarily, the terminal device may search for the broadcast signal of the first satellite through frequency scanning or beam scanning, synchronize with the first satellite, and obtain the first broadcast message.

[0121] In a possible implementation, the first indication information indicates ephemeris information of multiple satellites, and the method shown in FIG3 further includes step 303 .

[0122] 303. The terminal device selects a second satellite from multiple satellites based on the first indication information.

[0123] The orbital altitudes of the multiple satellites are lower than the orbital altitude of the first satellite, or the coverage area of ​​each satellite in the multiple satellites is smaller than the coverage area of ​​the first satellite. Exemplarily, the multiple satellites are located within the coverage area of ​​the first satellite.

[0124] For example, the first indication information may include an ephemeris information list, where the ephemeris information list includes the ephemeris information of the multiple satellites, or an offset of the ephemeris of the multiple satellites compared to the ephemeris of the first satellite. For example, the ephemeris information list may be as shown in Table 1, where Table 1 takes N satellites as an example, where satellite 1_1 corresponds to ephemeris information 1_1, ..., and satellite 1_N corresponds to ephemeris information 1_N.

[0125] Table 1

[0126] The terminal device may select the second satellite as the target access satellite from the multiple satellites according to a global navigation satellite system (GNSS) position of the terminal device.

[0127] As an example, the second satellite is one of the multiple satellites that is closer to the terminal device, or the second satellite is one of the multiple satellites whose distance to the terminal device is less than or equal to a distance threshold. For example, the second satellite may be the satellite that is closest to the terminal device among the multiple satellites. The distance threshold may be predefined by a network configuration or protocol, or determined by a service requirement or capability of the terminal device.

[0128] In this example, a second satellite that meets the conditions is selected from the multiple satellites based on the distances between the multiple satellites and the terminal device, thereby ensuring that the second satellite provides better access service for the terminal device.

[0129] As another example, the second satellite may be one of the multiple satellites with a longer service duration, or the second satellite may be one of the multiple satellites with a service duration greater than or equal to a time threshold. Exemplarily, the terminal device may determine the service durations of the multiple satellites based on their ephemeris information, and select a second satellite from the multiple satellites that meets the criteria based on the service durations. For example, the second satellite may be one of the multiple satellites with the longest service duration. It is understood that the time threshold may be predefined by network configuration or protocols, or determined by the service requirements of the terminal device.

[0130] In this example, the terminal device can select a second satellite whose service duration meets the requirements from the multiple satellites, thereby avoiding the terminal device from frequently switching service satellites, so that the second satellite can provide better access services for the terminal device.

[0131] As another example, the second satellite is one of the multiple satellites with higher signal quality, or the second satellite is one of the multiple satellites with signal quality greater than or equal to the signal quality threshold. Exemplarily, the signal quality of the second satellite can be represented by the reference signal receiving power (RSRP) or reference signal received quality (RSRQ) corresponding to the second satellite. For example, the larger the PSRP of the second satellite, the higher the signal quality of the second satellite. For another example, the larger the PSRQ of the second satellite, the higher the signal quality of the second satellite. The terminal device can determine the position or orientation of the multiple satellites based on the ephemeris information of the multiple satellites, and respectively receive the reference signals sent by the multiple satellites, thereby obtaining the signal quality of each satellite of the multiple satellites. The terminal device then selects the second satellite with higher signal quality or signal quality greater than or equal to the signal quality threshold from the multiple satellites as the target access satellite.

[0132] In this example, the terminal device may select a second satellite whose signal quality meets the requirements from multiple satellites, thereby ensuring the service quality when the second satellite provides access services to the terminal device.

[0133] 304. The second satellite sends a second broadcast message. Correspondingly, the terminal device receives the second broadcast message from the second satellite based on the first indication information.

[0134] Exemplarily, the terminal device determines the position or orientation of the second satellite based on the first indication information, and adjusts a receiving beam direction so that the receiving beam is directed toward the second satellite to monitor the broadcast signal of the second satellite. The second broadcast message may be a SIB message sent by the second satellite, and the terminal device can access the second satellite based on the second broadcast message.

[0135] In some possible implementations, after the terminal device receives the second broadcast message, the method shown in FIG3 further includes step 305 .

[0136] 305. The terminal device sends a preamble code, and correspondingly, the second satellite receives the preamble code.

[0137] The terminal device can perform an access procedure based on the preamble code (Msg1) to access the second satellite.

[0138] In this embodiment of the present application, the coverage area of ​​the first satellite is greater than the coverage area of ​​the second satellite. The first satellite can broadcast the ephemeris information of the second satellite, enabling the terminal device to obtain the ephemeris information of the second satellite and adjust the receiving beam direction based on the ephemeris information of the second satellite to point to the second satellite. The terminal device does not need to perform beam scanning, which can effectively shorten the time it takes for the terminal device to acquire the satellite and enable the terminal device to quickly access the second satellite.

[0139] In some possible implementations, the ephemeris information in the embodiments of the present application may also be replaced with position information or orbit information. That is, the first indication information indicates the position information or orbit information of the second satellite. For example, the first indication information may include the position information or orbit information of the second satellite. For another example, the first indication information may include the position information of the first satellite and the offset of the position of the second satellite compared to the position of the first satellite, or the first indication information may include the orbit information of the first satellite and the offset of the orbit of the second satellite compared to the orbit of the first satellite.

[0140] Please refer to Figure 4, which is a flow chart of another communication method provided in an embodiment of the present application. As shown in Figure 4, the method includes but is not limited to the following steps.

[0141] Optionally, the method shown in FIG4 may include step 401 .

[0142] 401. The second satellite sends first information. Correspondingly, the first satellite receives the first information, where the first information includes ephemeris information and SSB information of the second satellite.

[0143] 402: A first satellite sends a first broadcast message, and a terminal device receives the first broadcast message. The first broadcast message includes first indication information and SSB information of a second satellite, where the first indication information indicates ephemeris information of the second satellite.

[0144] As an example, the SSB information may include at least one of the following: the center frequency of the SSB, sub-carrier space (SCS), system frame number (SFN) offset, SSB transmission period, SSB time domain position information, half-frame index, and SSB measurement timing configuration (SMTC).

[0145] As another example, the first broadcast message may include an offset between the SSB information of the second satellite and the SSB information of the first satellite. For example, the first broadcast message may include the difference between the center frequency of the SSB of the second satellite and the center frequency of the SSB of the first satellite, the difference between the SSB transmission period of the second satellite and the SSB transmission period of the first satellite, the transmission time difference between the SSB of the second satellite and the SSB of the first satellite, etc.

[0146] In one possible implementation, the first broadcast message includes ephemeris information and SSB information for multiple satellites. For example, the ephemeris information and SSB information for the multiple satellites may be included in the first broadcast message in a table format. As shown in Table 2, taking N as an example, the first broadcast message may include the ephemeris information and SSB information for the N satellites.

[0147] Table 2

[0148] Optionally, the method shown in FIG4 may further include step 403 .

[0149] 403. The terminal device selects a second satellite from multiple satellites based on the first indication information.

[0150] The terminal device may select a second satellite from the multiple satellites as a target access satellite based on the GNSS position.

[0151] It is understandable that for the specific description of step 403, reference can be made to the relevant description in step 303, which will not be described in detail here.

[0152] It is understandable that for the specific description of the first broadcast message, the first indication information, and the second satellite, reference may be made to the relevant description in step 302 in FIG. 3 , which will not be described in detail here.

[0153] 404. The terminal device directs the receiving beam of the terminal device toward the second satellite based on the ephemeris information of the second satellite, and receives a second broadcast message from the second satellite at the SSB center frequency.

[0154] The terminal device can adjust the receiving beam direction of the terminal device based on the ephemeris information of the second satellite so that the receiving beam points to the second satellite, and listen to the broadcast signal of the second satellite on the center frequency of the SSB to receive the second broadcast message.

[0155] Exemplarily, the terminal device can also determine the time domain position of the SSB of the second satellite based on the SSB information of the second satellite, and listen to the broadcast signal of the second satellite at the time domain position of the SSB of the second satellite (such as during the period when the second satellite sends the SSB), and may not listen at other times, thereby saving power consumption of the terminal device.

[0156] In some possible implementations, after the terminal device receives the second broadcast message, the method shown in FIG4 further includes step 405 .

[0157] 405. The terminal device sends a preamble code, and correspondingly, the second satellite receives the preamble code.

[0158] The terminal device can perform an access procedure based on the preamble code to access the second satellite.

[0159] In this embodiment of the present application, the coverage range of the first satellite is greater than the coverage range of the second satellite. The first satellite can broadcast the ephemeris information and SSB information of the second satellite, eliminating the need for the terminal device to perform beam scanning and frequency sweeping. This can effectively shorten the time it takes for the terminal device to acquire the satellite, allowing the terminal device to quickly access the second satellite.

[0160] Please refer to Figure 5, which is a flow chart of another communication method provided in an embodiment of the present application. As shown in Figure 5, the method includes but is not limited to the following steps.

[0161] Optionally, the method shown in FIG5 may include step 501 .

[0162] 501. A second satellite sends first information. Correspondingly, a first satellite receives the first information. The first information includes ephemeris information of the second satellite and coverage of the second satellite.

[0163] 502. A first satellite sends a first broadcast message, and a terminal device receives the first broadcast message. The first broadcast message includes first indication information and second indication information, wherein the first indication information indicates ephemeris information of a second satellite, and the second indication information indicates a coverage range of the second satellite.

[0164] As an example, the second indication information indicates the longitude and latitude corresponding to the coverage range of the second satellite. The second indication information includes the longitude range and latitude range of the coverage range of the second satellite. The terminal device can determine whether the terminal device is within the coverage range of the second satellite based on the GNSS information of the terminal device. In this example, the second indication information indicates the longitude and latitude corresponding to the coverage range of the second satellite, so that the terminal device can quickly determine the coverage range of the second satellite based on the longitude and latitude.

[0165] As another example, the second indication information indicates the identifier of the geographical area corresponding to the coverage of the second satellite. In this example, the global geographical area can be divided into multiple geographical areas, and the multiple geographical areas can be numbered to obtain the identifier of each geographical area. The first satellite can determine the geographical area included in the coverage of the second satellite based on the interaction with the second satellite. For example, the second satellite reports the coverage area of ​​the second satellite to the first satellite, the first satellite obtains the coverage of the second satellite, and determines the geographical area included in the coverage of the second satellite, and broadcasts the identifier of the geographical area corresponding to the coverage of the second satellite through a first broadcast message. For another example, the second satellite reports the identifier of the geographical area included in the coverage of the second satellite to the first satellite, and the first satellite broadcasts the identifier of the geographical area corresponding to the coverage of the second satellite through a first broadcast message.

[0166] Exemplarily, the terminal device stores a mapping relationship between an identifier and a geographical area. The terminal device can determine the geographical area where the terminal device is located based on the GNSS information of the terminal device, and compare the identifier of the geographical area where the terminal device is located with the identifier of the geographical area corresponding to the coverage range of the second satellite to determine whether the terminal device is within the coverage range of the second satellite.

[0167] In this example, the coverage area of ​​the second satellite can be accurately indicated by identifying the geographical area corresponding to the coverage range of the second satellite.

[0168] As another example, the second indication information indicates the range of values ​​of the angle between the beam emitted by the second satellite and the plane formed by the antenna panel of the second satellite. The beam emitted by the second satellite can be received within the coverage range of the second satellite, so the coverage range of the second satellite can be indicated by the range of values ​​of the angle between the beam emitted by the second satellite and the plane formed by the antenna panel of the second satellite. For example, the second indication information may indicate the minimum value of the angle between the beam emitted by the second satellite and the plane formed by the antenna panel of the second satellite. The terminal device can determine whether the terminal device is within the coverage range of the second satellite by comparing whether the first angle is included in the range of values. The first angle is the angle formed by the line connecting the terminal device to the reference point on the plane formed by the antenna panel and the plane formed by the antenna panel.

[0169] Alternatively, the second indication information indicates the maximum value of the angle between the beam emitted by the second satellite and the normal of the antenna panel of the second satellite, where the normal of the antenna panel of the second satellite is perpendicular to the plane formed by the antenna panels of the second satellite. The maximum value of the angle between the beam emitted by the second satellite and the normal of the antenna panel of the second satellite can also be called the maximum scanning angle. As shown in Figure 6, the normal of the antenna panel of the second satellite points to the center of the earth. The terminal device determines the angle between the terminal device and the normal of the antenna panel of the second satellite based on the GNSS information of the terminal device and the ephemeris information of the second satellite. If the angle between the line connecting the terminal device to the reference point on the antenna panel and the normal of the antenna panel is less than the maximum scanning angle of the second satellite, then the terminal device is within the coverage range of the second satellite.

[0170] Exemplarily, the second indication information may also indicate the angle between the plane formed by the antenna panel and the ground, or the angle between the normal of the antenna panel and the ground. When the plane formed by the antenna panel of the second satellite is not parallel to the ground or the normal of the antenna panel of the second satellite does not point to the center of the earth, the terminal device may determine the coverage range of the second satellite based on the value range of the angle between the beam emitted by the second satellite and the plane formed by the antenna panel of the second satellite, and the angle between the plane formed by the antenna panel and the ground, or the angle between the normal of the antenna panel and the ground, thereby determining whether the terminal device is located within the coverage range of the second satellite.

[0171] Exemplarily, the second indication information further indicates the coverage of multiple satellites. For example, the ephemeris information and coverage of the multiple satellites may be included in the first broadcast message in a tabular format. As shown in Table 3, taking N as an example, the first broadcast message may include the ephemeris information and coverage of the N satellites, where the ephemeris information of satellite 1_1 is ephemeris information 1_1 and the coverage is coverage range 1_1.

[0172] Table 3

[0173] Optionally, the method shown in FIG5 further includes step 503 .

[0174] 503. The terminal device selects a second satellite from multiple satellites based on the second indication information.

[0175] Exemplarily, the terminal device is located within the coverage of the second satellite. The terminal device can determine that the terminal device is located within the coverage of the second satellite based on the GNSS position and the second indication information, and select the second satellite as the target access satellite. The terminal device can select a satellite covering the terminal device from the multiple satellites as an alternative satellite based on the GNSS position, and the alternative satellite includes the second satellite. When the number of the alternative satellites is 1, the terminal device selects the satellite (i.e., the second satellite) as the target access satellite and accesses the satellite. When the number of alternative satellites is greater than 1, the second satellite is the satellite that meets the conditions among the alternative satellites. For example, the second satellite is one of the alternative satellites that is closer to the terminal device, or the second satellite is one of the alternative satellites with a longer service time, or the second satellite is one of the alternative satellites with higher signal quality.

[0176] 504. The second satellite broadcasts a second broadcast message. Accordingly, the terminal device receives the second broadcast message from the second satellite based on the first indication information.

[0177] It is understandable that the specific implementation of step 504 can refer to the specific implementation of step 304 in Figure 3, which will not be described in detail here.

[0178] It is understandable that for the specific description of the first broadcast message, the first indication information, and the second satellite, reference may be made to the relevant description in step 302 in FIG. 3 , which will not be described in detail here.

[0179] In some possible implementations, after the terminal device receives the second broadcast message, the method shown in FIG5 further includes step 505 .

[0180] 505. The terminal device sends a preamble code, and correspondingly, the second satellite receives the preamble code.

[0181] The terminal device can perform an access procedure based on the preamble code to access the second satellite.

[0182] In an embodiment of the present application, the first satellite can broadcast the ephemeris information and coverage range of the second satellite so that the terminal device can determine whether it is within the coverage range of the second satellite, so that the terminal device can access the second satellite more quickly, greatly reducing the time it takes for the terminal device to capture the satellite.

[0183] Please refer to Figure 7, which is a flow chart of another communication method provided in an embodiment of the present application. As shown in Figure 7, the method includes but is not limited to the following steps.

[0184] Optionally, the method shown in FIG7 may include step 701 .

[0185] 701. A second satellite sends first information to a first satellite, and the first satellite receives the first information. The first information includes ephemeris information of the second satellite and load status of the second satellite.

[0186] 702. A first satellite sends a first broadcast message, and a terminal device receives the first broadcast message. The first broadcast message includes first indication information and third indication information. The first indication information indicates ephemeris information of a second satellite, and the third indication information indicates a load condition of the second satellite.

[0187] Exemplarily, the third indication information includes the number of users currently connected to the second satellite and / or the ratio of the number of users currently connected to the second satellite to the number of users allowed to be connected to the second satellite.

[0188] Optionally, the first indication information indicates ephemeris information of multiple satellites, and the third indication information indicates load conditions of the multiple satellites. The ephemeris information and load conditions of the multiple satellites may be included in the first broadcast message in a tabular format. As shown in Table 4, taking N as an example, the first broadcast message may include the ephemeris information and coverage conditions of the N satellites, where the ephemeris information of satellite 1_1 is ephemeris information 1_1, and the load condition is load condition 1_1.

[0189] Table 4

[0190] Optionally, the method shown in FIG7 may further include step 703 .

[0191] 703. The terminal device selects the second satellite from the multiple satellites according to the GNSS information, the first indication information, and the third indication information.

[0192] Exemplarily, the second satellite is a satellite with a higher load among the multiple satellites. That is, the terminal device may select the satellite with a higher load from the multiple satellites based on the load of the multiple satellites. For example, the second satellite may be one of the multiple satellites with a smaller number of currently connected users, or the second satellite may be one of the multiple satellites with a smaller ratio of the number of currently connected users to the number of users allowed to connect.

[0193] 704. The second satellite broadcasts a second broadcast message. Accordingly, the terminal device receives the second broadcast message from the second satellite based on the first indication information.

[0194] It is understandable that the specific implementation of step 704 can refer to the specific implementation of step 304 in Figure 3, which will not be described in detail here.

[0195] It is understandable that for the specific description of the first broadcast message, the first indication information, and the second satellite, reference may be made to the relevant description in step 302 in FIG. 3 , which will not be described in detail here.

[0196] In some possible implementations, after the terminal device receives the second broadcast message, the method shown in FIG7 further includes step 705 .

[0197] 705. The terminal device sends a preamble code, and correspondingly, the second satellite receives the preamble code.

[0198] The terminal device can perform an access procedure based on the preamble code to access the second satellite.

[0199] In an embodiment of the present application, the first satellite can broadcast the ephemeris information and load conditions of the second satellite, so that the terminal device can select a more suitable second satellite based on the load conditions, ensure load balancing between satellites, avoid long subsequent access time caused by congestion, and ensure that the second satellite can provide better access services for the terminal device.

[0200] It is understood that the various embodiments shown above can be combined with each other, that is, the first broadcast message includes the first indication information and at least one of the SSB information, the second indication information, or the third indication information. For example, the method shown in Figure 4 can be combined with the method shown in Figure 5, that is, the first broadcast message includes the first indication information, the SSB information, and the second indication information, which will not be described in detail here.

[0201] The following describes the device provided in the embodiments of the present application.

[0202] The present application divides the functional modules of the communication device according to the above-mentioned method embodiment. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in this application is schematic and is only a logical functional division. There may be other division methods in actual implementation. The communication device of the embodiment of the present application will be described in detail below with reference to Figures 8 to 10.

[0203] Figure 8 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application. As shown in Figure 8, the communication device includes a processing unit 801 and a transceiver unit 802. The transceiver unit 802 can implement corresponding communication functions, and the processing unit 801 is used to process data. For example, the transceiver unit 802 can also be referred to as a communication interface or a communication unit.

[0204] In some embodiments of the present application, the communication device can be used to execute the actions performed by the terminal device in the above method embodiments. In this case, the communication device can be a terminal device or a terminal device, or the communication device can be a component that can be configured in the terminal device (such as a chip or system, etc.), and the transceiver unit 802 is used to execute the transceiver-related operations of the terminal device in the above method embodiments, and the processing unit 801 is used to execute the terminal device processing-related operations in the above method embodiments.

[0205] Exemplarily, the transceiver unit 802 is configured to receive a first broadcast message from a first satellite; the processing unit 801 is configured to receive a second broadcast message from a second satellite via the transceiver unit 802 based on the first indication information.

[0206] It is understandable that specific descriptions of the first satellite, the first broadcast message, the first indication information, the second satellite, the second broadcast message, etc. can be referred to the method embodiment shown above, and will not be described in detail here.

[0207] In other embodiments of the present application, the communication device can be used to execute the actions performed by the first satellite in the above method embodiment. In this case, the communication device can be the first satellite, or the communication device can be or can be configured as a component of the first satellite (such as a chip or system, etc.), the transceiver unit 802 is used to execute the transceiver-related operations of the first satellite in the above method embodiment, and the processing unit 801 is used to execute the processing-related operations of the first satellite in the above method embodiment.

[0208] Exemplarily, the processing unit 801 is configured to obtain ephemeris information of a second satellite; and the transceiver unit 802 is configured to send a first broadcast message.

[0209] Optionally, the transceiver unit 802 is further configured to receive first information.

[0210] It is understandable that specific descriptions of the first satellite, the first broadcast message, the first indication information, the second satellite, the second broadcast message, the first information, etc. can be referred to the method embodiment shown above, and will not be described in detail here.

[0211] In some other embodiments of the present application, the communication device can be used to execute the actions performed by the second satellite in the above method embodiments. In this case, the communication device can be the second satellite, or the communication device can be or can be configured as a component of the second satellite (such as a chip or system, etc.), the transceiver unit 802 is used to execute the transceiver-related operations of the second satellite in the above method embodiments, and the processing unit 801 is used to execute the second satellite processing-related operations in the above method embodiments.

[0212] Exemplarily, the transceiver unit 802 is configured to send the first information and the second broadcast message.

[0213] It is understandable that specific descriptions of the first information, the second broadcast message, etc. can be referred to the method embodiment shown above and will not be described in detail here.

[0214] Optionally, the above-mentioned communication device may further include a storage unit, which may be used to store instructions and / or data. The processing unit 801 may read the instructions and / or data in the storage unit so that the communication device implements the above-mentioned method embodiment.

[0215] It can be understood that the specific description of the transceiver unit and the processing unit shown in the embodiment of the present application is only an example. For the specific functions or execution steps of the transceiver unit and the processing unit, please refer to the above-mentioned method embodiment and will not be described in detail here.

[0216] The above describes the communication device according to the embodiment of the present application. The following describes possible product forms of the communication device. It should be understood that any product having the functions of the communication device described in FIG. 7 falls within the scope of protection of the embodiment of the present application. It should also be understood that the following description is merely illustrative and does not limit the product forms of the communication device according to the embodiment of the present application to these examples.

[0217] In one possible implementation, in the communication device shown in FIG8 , the processing unit 801 may be one or more processors, the transceiver unit 802 may be a transceiver, or the transceiver unit 802 may be a transmitting unit and a receiving unit, the transmitting unit may be a transmitter, the receiving unit may be a receiver, and the transmitting unit and the receiving unit are integrated into a single device, such as a transceiver. In the embodiment of the present application, the processor and the transceiver may be coupled, etc., and the embodiment of the present application does not limit the connection method between the processor and the transceiver. During the execution of the above method, the process of sending information in the above method can be understood as the process of the processor outputting the above information. When outputting the above information, the processor outputs the above information to the transceiver so that the transceiver can transmit it. After being output by the processor, the above information may also need to undergo other processing before reaching the transceiver. Similarly, the process of receiving information in the above method can be understood as the process of the processor receiving the input information. When the processor receives the input information, the transceiver receives the above information and inputs it into the processor. Furthermore, after the transceiver receives the above information, the above information may need to be processed further before being received by the processor.

[0218] As shown in FIG. 9 , the communication device 90 includes one or more processors 920 and a transceiver 910 .

[0219] In some embodiments of the present application, the communication device can be used to execute the steps or functions performed by the terminal device in the above method embodiments.

[0220] Exemplarily, the transceiver 910 is configured to receive a first broadcast message from a first satellite; and the processor 920 is configured to receive a second broadcast message from a second satellite via the transceiver 910 based on the first indication information.

[0221] In other embodiments of the present application, the communication device may be used to execute the steps or functions performed by the first satellite in the above method embodiments.

[0222] Exemplarily, the processor 920 acquires ephemeris information of the second satellite; and the transceiver 910 is configured to send the first broadcast message.

[0223] In some further embodiments of the present application, the communication device may be used to execute the steps or functions performed by the second satellite in the above method embodiments.

[0224] Exemplarily, the transceiver 910 is configured to send the first information and the second broadcast message.

[0225] It will be understood that the specific descriptions of the transceiver and processor shown in the embodiments of the present application are merely examples. For the specific functions or execution steps of the transceiver and processor, reference may be made to the above-mentioned method embodiments, which will not be described in detail here.

[0226] In the above embodiments, the description of the first satellite, the first broadcast message, the first indication information, the second satellite, the second broadcast message, the first information, etc. can also refer to the introduction in the above method embodiment, and will not be described in detail here.

[0227] In various implementations of the communication device shown in FIG9 , the transceiver may include a receiver and a transmitter, wherein the receiver is configured to perform a receiving function (or operation) and the transmitter is configured to perform a transmitting function (or operation). The transceiver is configured to communicate with other devices / devices via a transmission medium.

[0228] Optionally, the communication device 90 may further include one or more memories 930 for storing program instructions and / or data, etc. The memory 930 is coupled to the processor 920. The coupling in the embodiment of the present application is an indirect coupling or communication connection between devices, units or modules, which can be electrical, mechanical or other forms, and is used for information exchange between devices, units or modules. The processor 920 may operate in conjunction with the memory 930. The processor 920 may execute program instructions stored in the memory 930. Optionally, at least one of the above-mentioned one or more memories may be included in the processor.

[0229] The specific connection medium between the transceiver 910, processor 920, and memory 930 is not limited in the embodiments of the present application. In Figure 9, the memory 930, processor 920, and transceiver 910 are connected via a bus 940. The bus is represented by a bold line in Figure 9. The connection methods between other components are only for illustrative purposes and are not limiting. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, Figure 9 only uses a single bold line, but this does not mean that there is only one bus or only one type of bus.

[0230] In the embodiments of the present application, the processor may be a general-purpose 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., and may implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the methods disclosed in the embodiments of the present application may be directly implemented as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor, etc.

[0231] In the embodiment of the present application, memory may include but is not limited to non-volatile memories such as hard disk drive (HDD) or solid-state drive (SSD), random access memory (RAM), erasable programmable read-only memory (EPROM), read-only memory (ROM) or portable read-only memory (CD-ROM), etc. Memory is any storage medium that can be used to carry or store program code in the form of instructions or data structures, and can be 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 embodiment of the present application can also be a circuit or other arbitrarily capable of realizing a storage function, for storing program instructions and / or data.

[0232] Illustratively, the processor 920 is primarily used to process communication protocols and communication data, control the entire communication device, execute software programs, and process software program data. The memory 930 is primarily used to store software programs and data. The transceiver 910 may include a control circuit and an antenna. The control circuit is primarily used to convert baseband signals into radio frequency signals and process radio frequency signals. The antenna is primarily used to transmit and receive radio frequency signals in the form of electromagnetic waves. Input / output devices, such as a touch screen, display, and keyboard, are primarily used to receive user input and output data to the user.

[0233] When the communication device is powered on, the processor 920 can read the software program in the memory 930, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor 920 performs baseband processing on the data to be sent and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal and then transmits the radio frequency signal to the outside in the form of electromagnetic waves 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 a baseband signal, and outputs the baseband signal to the processor 920. The processor 920 converts the baseband signal into data and processes the data.

[0234] In another implementation, the RF circuit and antenna may be provided independently of the processor performing baseband processing. For example, in a distributed scenario, the RF circuit and antenna may be remotely arranged independent of the communication device.

[0235] It is understood that the communication device shown in the embodiment of the present application may also have more components than those in Figure 9, and the embodiment of the present application is not limited to this. The method performed by the processor and transceiver shown above is only an example. For the specific steps performed by the processor and transceiver, please refer to the method described above.

[0236] In another possible implementation, in the communication device shown in FIG8 , the processing unit 801 may be one or more logic circuits, and the transceiver unit 802 may be an input / output interface, or may be called a communication interface, or an interface circuit, or an interface, etc. Alternatively, the transceiver unit 802 may be a sending unit and a receiving unit, the sending unit may be an output interface, the receiving unit may be an input interface, and the sending unit and the receiving unit are integrated into one unit, such as an input / output interface. As shown in FIG10 , the communication device shown in FIG10 includes a logic circuit 1001 and an interface 1002. That is, the processing unit 801 may be implemented using a logic circuit 1001, and the transceiver unit 802 may be implemented using an interface 1002. The logic circuit 1001 may be a chip, a processing circuit, an integrated circuit, or a system on chip (SoC) chip, etc., and the interface 1002 may be a communication interface, an input / output interface, a pin, etc. For example, FIG10 is illustrated using the communication device as a chip, and the chip includes a logic circuit 1001 and an interface 1002.

[0237] In the embodiment of the present application, the logic circuit and the interface may also be coupled to each other. The embodiment of the present application does not limit the specific connection method between the logic circuit and the interface.

[0238] In some embodiments of the present application, the communication device can be used to execute the steps or functions performed by the terminal device in the above method embodiments. For example, interface 1002 is used to input a first broadcast message; logic circuit 1001 is used to input a second broadcast message through interface 1002 based on the first indication information.

[0239] In other embodiments of the present application, the communication device can be used to execute the steps or functions performed by the first satellite in the above method embodiments. For example, logic circuit 1001 is used to obtain ephemeris information of the second satellite; interface 1002 is used to output the first broadcast message. Optionally, interface 1002 is also used to input the first information.

[0240] In some other embodiments of the present application, the communication device may be used to execute the steps or functions executed by the second satellite in the above method embodiments. Exemplarily, the interface 1002 is used to output the first information and the second broadcast message.

[0241] It can be understood that the specific description of the logic circuit and interface shown in the embodiments of the present application is only an example. For the specific functions or execution steps of the logic circuit and interface, please refer to the above-mentioned method embodiment and will not be described in detail here.

[0242] In the above embodiments, the description of the first satellite, the first broadcast message, the first indication information, the second satellite, the second broadcast message, the first information, etc. can also refer to the introduction in the above method embodiment, and will not be described in detail here.

[0243] It can be understood that the communication device shown in the embodiment of the present application can implement the method provided in the embodiment of the present application in the form of hardware, or can implement the method provided in the embodiment of the present application in the form of software, etc., and the embodiment of the present application is not limited to this.

[0244] An embodiment of the present application further provides a communication system, which includes at least two of the following: a terminal device, a first satellite, and a second satellite. The terminal device, the first satellite, and the second satellite are used to execute the method in any of the aforementioned embodiments.

[0245] In addition, the present application also provides a computer program, which is used to implement the operations and / or processing performed by the terminal device in the method provided by the present application.

[0246] The present application also provides a computer program, which is used to implement the operations and / or processing performed by the first satellite in the method provided by the present application.

[0247] The present application also provides a computer program, which is used to implement the operations and / or processing performed by the second satellite in the method provided by the present application.

[0248] The present application also provides a computer-readable storage medium, which stores computer code. When the computer code runs on a computer, the computer executes the operations and / or processing performed by the terminal device in the method provided by the present application.

[0249] The present application also provides a computer-readable storage medium, which stores computer code. When the computer code is executed on a computer, the computer executes the operations and / or processing performed by the first satellite in the method provided by the present application.

[0250] The present application also provides a computer-readable storage medium, which stores computer code. When the computer code runs on a computer, it enables the computer to execute the operations and / or processing performed by the second satellite in the method provided by the present application.

[0251] The present application also provides a computer program product, which includes computer code or computer program. When the computer code or computer program is run on a computer, the operations and / or processing performed by the terminal device in the method provided by the present application are executed.

[0252] The present application also provides a computer program product, which includes computer code or computer program. When the computer code or computer program runs on a computer, the operations and / or processing performed by the first satellite in the method provided by the present application are executed.

[0253] The present application also provides a computer program product, which includes computer code or computer program. When the computer code or computer program runs on a computer, the operations and / or processing performed by the second satellite in the method provided by the present application are executed.

[0254] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or can be electrical, mechanical or other forms of connection.

[0255] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the technical effects of the solutions provided in the embodiments of the present application.

[0256] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0257] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a readable storage medium, including a number of instructions for enabling 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 method described in each embodiment of the present application. The aforementioned readable storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0258] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A communication method, characterized in that, Applied to a terminal device, including: Receiving a first broadcast message from a first satellite, the first broadcast message including first indication information indicating ephemeris information of a second satellite; Receiving a second broadcast message from the second satellite based on the first indication information.

2. A communication method, characterized in that, Applied to the first satellite, including: Obtaining ephemeris information of the second satellite; Sending a first broadcast message, the first broadcast message including first indication information indicating the ephemeris information of the second satellite.

3. The method according to claim 2, wherein The obtaining the ephemeris information of the second satellite includes: Receiving first information from the second satellite, the first information including the ephemeris information of the second satellite.

4. The method according to claim 3, wherein The first information further includes at least one of the following: synchronization signal block (SSB) information of the second satellite, coverage area of the second satellite, and load condition of the second satellite.

5. The method according to any one of claims 1-4, characterized in that, The first broadcast message further includes at least one of the following: SSB information of the second satellite, second indication information, or third indication information; wherein the second indication information is used to indicate the coverage area of the second satellite, and the third indication information is used to indicate the load condition of the second satellite.

6. According to the method of claim 5, the second indication information indicates the longitude and latitude corresponding to the coverage area of the second satellite.

7. The method according to claim 5, wherein The second indication information indicates an identifier of a geographical area corresponding to the coverage area of the second satellite.

8. The method according to claim 5, wherein The second indication information indicates a value range of an angle formed by a beam emitted by the second satellite and a plane formed by an antenna panel of the second satellite.

9. The method according to claim 5, characterized in that The third indication information includes the number of currently connected users of the second satellite and / or a ratio of the number of currently connected users of the second satellite to the number of users allowed to be connected to the second satellite.

10. The method according to claim 5, wherein The SSB information includes at least one of the following information of the second satellite: SSB center frequency, subcarrier spacing (SCS), system frame number (SFN) offset, SSB transmission period, SSB time domain information, and half-frame index.

11. The method according to any one of claims 1-10, characterized in that, The first indication information includes the ephemeris information of the first satellite and an offset of the ephemeris of the second satellite relative to the ephemeris of the first satellite.

12. The method according to any one of claims 1-11, characterized in that, The first broadcast message further includes fourth indication information, and the fourth indication information is used to indicate that the first broadcast message further includes access information of the first satellite.

13. The method according to any one of claims 1-12, characterized in that, The first indication information indicates ephemeris information of multiple satellites, and the second satellite is one of the multiple satellites that is closer to the terminal device, or the second satellite is one of the multiple satellites whose distance from the terminal device is less than or equal to a distance threshold.

14. The method according to any one of claims 1 to 12, characterized in that, The first indication information indicates ephemeris information of multiple satellites, and the second satellite is one of the multiple satellites with a longer service duration, or the second satellite is one of the multiple satellites whose service duration is greater than or equal to a time threshold.

15. The method according to any one of claims 1-12, characterized in that, The first indication information indicates ephemeris information of multiple satellites, and the second satellite is one of the multiple satellites with higher signal quality, or the second satellite is one of the multiple satellites whose signal quality is greater than or equal to a signal quality threshold.

16. A communication method, characterized in that, Applied to the second satellite, including: Send first information to a first satellite, where the first information includes ephemeris information of a second satellite; Send a second broadcast message.

17. The method according to claim 16, wherein The first information further includes at least one of the following: synchronization signal block (SSB) information of the second satellite, coverage area of the second satellite, and load condition of the second satellite.

18. A communication device, characterized in that, Comprises units for performing the method according to any one of claims 1-17.

19. A communication device, characterized in that, Comprises a processor and a memory; The memory is used for storing instructions; The processor is used for executing the instructions to cause the method according to any one of claims 1-17 to be executed.

20. A communication device, characterized in that, Comprises a logic circuit and an interface, and the logic circuit and the interface are coupled; The interface is used for inputting and / or outputting code instructions, and the logic circuit is used for executing the code instructions to cause the method according to any one of claims 1-17 to be executed.

21. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used for storing a computer program, and when the computer program is executed, the method according to any one of claims 1-17 is executed.

22. A computer program, characterized in that, When the computer program is executed, the method according to any one of claims 1-17 is executed.

23. A communication system, characterized in that, The communication system includes at least two of the following: a terminal device, a first satellite, and a second satellite. The terminal device is used for performing the method according to claim 1 or any one of claims 5-15. The first satellite is used for performing the method according to any one of claims 2-15. The second satellite is used for performing the method according to claim 16 or 17.

Images