Cross-satellite communication method for high-dynamic terminal

Abstract

The invention discloses a cross-satellite communication method for a high-dynamic terminal. The cross-satellite communication method comprises the following steps: a satellite carries out bidirectional communication with a terminal and a terminal control station; the satellite forwards terminal service information to the terminal control station, and forwards terminal control station preset information and signaling information to the terminal; according to the preset information and the signaling information, the terminal dynamically judges whether cross-satellite switching needs to be initiated or not; if cross-satellite switching needs to be carried out, the terminal changes parameters according to the content of the signaling information to realize communication with a target satellite, and the target satellite forwards terminal service information to a terminal control station; meanwhile, terminal state information is updated and sent to the terminal control station, and the whole cross-satellite communication process is completed. According to the invention, on the premise of ensuring continuous and reliable cross-satellite communication, the cross-satellite communication process is simplified, and a self-adaptive coding modulation mode is adopted in an uplink, so that cross-satellite rapid switching and efficient communication of the high-dynamic terminal in a satellite networking scene are realized.

Description

Technical Field

[0001] The present invention relates to an inter-satellite communication method for a high-dynamic terminal, belongs to the field of satellite communications, and can be used for the inter-satellite communication of a high-dynamic terminal in a satellite constellation networking scenario to achieve continuous and reliable communication of the high-dynamic terminal. Background Art

[0002] With the development of the field of satellite communications, satellite communication systems based on a single high-orbit satellite can no longer meet user needs, and satellite communication systems are rapidly shifting to multi-satellite networking and satellite constellation networking. In view of the topological changes of the satellite constellation itself and the high-speed movement characteristics of high-dynamic terminals, a single satellite beam and a single satellite can no longer meet the continuous communication needs of such terminals, which has brought about the need for inter-satellite communication. At the same time, the traditional inter-satellite communication solution has a complex interaction process and a long switching time, which is not suitable for the requirements of high-dynamic terminals for fast switching. Therefore, it is urgent to design an inter-satellite communication solution for the special needs of high-dynamic terminals to achieve continuous and reliable communication services. Summary of the invention

[0003] The present invention proposes an inter-satellite communication method for a high-dynamic terminal, which adopts a simplified inter-satellite communication process to achieve inter-satellite rapid switching and efficient communication of the high-dynamic terminal under the premise of ensuring continuous and reliable communication.

[0004] The technical solution of the present invention is:

[0005] An inter-satellite communication method for a high-dynamic terminal, comprising:

[0006] The satellite has two-way communication with the terminal and the terminal control station;

[0007] The satellite forwards the terminal service information to the terminal control station, and the satellite forwards the terminal control station preset information and signaling information to the terminal;

[0008] Based on the preset information and signaling information, the terminal dynamically determines whether to initiate an inter-satellite handover;

[0009] If inter-satellite switching is required, the terminal sends an inter-satellite switching request signal and forwards it to the destination satellite via the inter-satellite link;

[0010] After the destination satellite performs user authentication and authorization, it allocates and reserves resources for the terminal and sends signaling information to the terminal;

[0011] The terminal changes parameters according to the signaling information content to achieve communication with the destination satellite. The destination satellite forwards the terminal business information to the terminal control station. At the same time, the terminal status information is updated and sent to the terminal control station to complete the entire inter-satellite communication process.

[0012] Optionally, the satellite and the terminal and the terminal control station implement two-way communication including inter-satellite communication of satellite downlink and inter-satellite communication of satellite uplink;

[0013] The inter-satellite communication of the satellite downlink adopts a fixed allocation mode, that is, each satellite beam on the terminal operation path reserves downlink resources in advance to ensure communication with the terminal;

[0014] The inter-satellite communication of the satellite uplink adopts a dynamic access mode, that is, each satellite beam on the terminal's operating path dynamically allocates uplink resources to communicate with the terminal according to the current satellite resource usage.

[0015] Optionally, the terminal predicts a downlink reception signal-to-noise ratio for a subsequent period of time according to preset information and signaling information, and determines whether inter-satellite switching is required;

[0016] If inter-satellite switching is required, the terminal selects and determines the destination satellite for the inter-satellite switching, and sends an inter-satellite switching request signal to the currently connected satellite through the uplink; otherwise, the inter-satellite switching is not performed and the original uplink and downlink communication links are maintained.

[0017] Optionally, the preset information includes satellite ephemeris, satellite beam and downlink parameter information; the signaling information includes uplink parameter information and uplink receiving signal-to-noise ratio.

[0018] Optionally, the method includes the following steps:

[0019] (1) The terminal control station sends preset information to the terminal via satellite forwarding;

[0020] (2) The terminal obtains information such as satellite ephemeris, satellite beam, and downlink parameters through the preset information forwarded by the satellite downlink; the terminal obtains uplink parameter information and uplink receiving signal-to-noise ratio through the signaling information sent by the satellite downlink;

[0021] (3) The terminal uses machine learning and other methods to dynamically predict the downlink received signal-to-noise ratio for a period of time based on its own position, received downlink signal strength, and known satellite ephemeris and satellite beam information, and uses this to determine whether inter-satellite handover is required;

[0022] (4) If inter-satellite switching is required, the terminal selects and determines the target satellite for inter-satellite switching, and sends an inter-satellite switching request signal to the currently connected satellite through the uplink; otherwise, the inter-satellite switching is not performed and the original uplink and downlink communication links are maintained;

[0023] (5) After receiving the inter-satellite handover request signal, the currently connected satellite forwards the inter-satellite handover request to the destination satellite through the inter-satellite link;

[0024] (6) After receiving the inter-satellite handover request, the destination satellite performs user authentication and authorization, allocates and reserves uplink resources for the terminal, and sends signaling information to the terminal via the downlink;

[0025] (7) After sending the inter-satellite handover request signal, the terminal uses the downlink parameters of the destination satellite for communication. After receiving the signaling information sent by the destination satellite downlink, the terminal changes the uplink parameters according to the signaling information content to achieve uplink communication with the destination satellite;

[0026] (8) After receiving the uplink signal from the terminal, the destination satellite forwards the terminal service information to the terminal control station. At the same time, the terminal status information is updated and sent to the terminal control station, thus completing the entire inter-satellite communication process.

[0027] Optionally, while initiating the inter-satellite handover, the adaptive coding modulation mode is also switched, specifically including:

[0028] In the uplink design, according to the requirements of uplink minimum system margin, n coding modulation schemes with different bit error rate thresholds are selected to form a set, and arranged from small to large according to the bit error rate threshold as the alternative uplink coding modulation schemes, denoted as {Modcod1, Modcod2, …Modcod n};

[0029] Set the upshift threshold L up and downshift threshold L down , then corresponding to n coding modulation modes, there is a set of upshift thresholds Downshift threshold set

[0030] When the uplink coding modulation mode adopts Modcod i , i = 1, 2, 3...n, when the uplink receive signal-to-noise ratio increases and is greater than When the uplink coding modulation mode is switched to Modcod i+1 ; When the uplink coding modulation mode adopts Modcod i , the predicted uplink received signal-to-noise ratio will decrease and be less than When the uplink coding modulation mode is switched to Modcod i-1 ; Otherwise, maintain Modcod i constant.

[0031] The advantages of the present invention compared with the prior art are:

[0032] The inter-satellite communication method for high-dynamic terminals of the present invention simplifies the inter-satellite communication process while ensuring the continuity and reliability of inter-satellite communication, and adopts an adaptive coding modulation method in the uplink to achieve rapid inter-satellite switching and efficient communication of high-dynamic terminals in satellite networking scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0034] Figure 1 It is a flowchart of the inter-satellite communication process for high dynamic terminals;

[0035] Figure 2 The flowchart of switching the uplink coding and modulation mode for high dynamic terminals is shown in FIG. DETAILED DESCRIPTION

[0036] The following detailed description of the present invention is exemplary and does not limit the scope of the present invention. Based on the embodiments of the present invention, for ordinary technicians in the field, all uncreative improvements should be considered as the protection scope of the present invention without departing from the present invention.

[0037] The present invention discloses an overall architecture of an inter-satellite communication method for a high-dynamic terminal in a satellite networking scenario, comprising: a satellite, a terminal, and a terminal control station.

[0038] The satellite realizes two-way communication with the terminal and the terminal control station; dynamically allocates uplink resources according to the inter-satellite switching request signal sent by the terminal; forwards the terminal service information to the terminal control station and forwards the terminal control station preset information to the terminal; and forwards the inter-satellite switching request signal to the destination satellite through the inter-satellite link.

[0039] The terminal realizes two-way communication with the satellite and dynamically determines whether it is necessary to initiate inter-satellite switching and uplink coding and modulation mode switching.

[0040] The terminal control station realizes two-way communication with the satellite.

[0041] The high dynamic terminal inter-satellite communication process of the present invention is shown in Figure 1 , the high dynamic terminal uplink coding modulation mode switching process is shown in Figure 2. In actual application, the inter-satellite communication of the satellite downlink adopts a fixed allocation mode, that is, each satellite beam on the terminal operation path reserves downlink resources in advance to ensure communication with the terminal. The inter-satellite communication of the satellite uplink adopts a dynamic access mode, that is, each satellite beam on the terminal operation path dynamically allocates uplink resources to communicate with the terminal according to the current satellite resource usage. In particular, the satellite uplink also adopts an adaptive coding and modulation method, which enables the terminal to dynamically change the coding and modulation method according to the current uplink margin, thereby further improving the uplink communication rate.

[0042] Without loss of generality, the following describes the specific inter-satellite switching process by taking a system with two satellites, one terminal, and one terminal control station as an example.

[0043] High dynamic terminal inter-satellite communication process:

[0044] (1) The terminal control station sends preset information to the terminal via satellite 1;

[0045] (2) The terminal obtains all satellite ephemeris, satellite beam, downlink parameters and other information through the preset information forwarded by satellite 1 downlink. The terminal obtains uplink parameter information and uplink receiving signal-to-noise ratio through the signaling information sent by satellite 1 downlink;

[0046] (3) The terminal uses machine learning and other methods to dynamically predict the downlink reception signal-to-noise ratio of satellite 1 and satellite 2 in the following period of time based on its own position, the strength of the downlink signal received from satellite 1, and all known satellite ephemeris and satellite beam information, and uses this to determine whether inter-satellite switching is required;

[0047] (4) If inter-satellite switching to satellite 2 is required, the terminal sends an inter-satellite switching request signal to satellite 1 via the uplink. Otherwise, inter-satellite switching is not performed and the original uplink and downlink communication links are maintained;

[0048] (5) After receiving the inter-satellite handover request signal, satellite 1 forwards the inter-satellite handover request to satellite 2 via the inter-satellite link;

[0049] (6) After receiving the inter-satellite handover request, Satellite 2 performs user authentication and authorization, allocates and reserves uplink resources of Satellite 2 for the terminal, and sends signaling information to the terminal through the downlink of Satellite 2;

[0050] (7) After sending the inter-satellite handover request signal, the terminal uses the downlink parameters of satellite 2 for communication. After receiving the signaling information sent by the downlink of satellite 2, the terminal changes the uplink parameters according to the content of the signaling information to achieve uplink communication with satellite 2;

[0051] (8) After receiving the uplink signal from the terminal, satellite 2 forwards the terminal service information to the terminal control station. At the same time, the terminal status information is updated and sent to the terminal control station, thus completing the entire inter-satellite communication process.

[0052] In the coding modulation mode set {Modcod1, Modcod2, …Modcod n}、Upshift threshold set Downshift threshold set Among them, the upshift threshold L up and downshift threshold L down For the selection, existing methods such as shift threshold can be used to ensure the reliability of the communication link; after the setting is completed according to the method of the present invention, the high dynamic terminal uplink coding modulation mode switching process:

[0053] (1) During the operation of the terminal, according to its own position, the strength of the downlink signal received by satellite 1, the uplink received signal-to-noise ratio in the downlink signaling information of satellite 1, and the known satellite 1 ephemeris and satellite 1 beam information, the existing methods such as machine learning are used to dynamically predict the uplink received signal-to-noise ratio of satellite 1 for a subsequent period of time, and thereby control the switching of the coding and modulation mode of the uplink of satellite 1;

[0054] (2) When the uplink coding modulation mode of satellite 1 adopts Modcod i , i = 1, 2, 3 ... n, the predicted uplink receiving signal-to-noise ratio in the subsequent period of time increases and is greater than When the uplink coding modulation mode is switched to Modcod i+1 ; When the uplink coding modulation mode of satellite 1 adopts Modcod i , the predicted uplink received signal-to-noise ratio will decrease and be less than When the uplink coding modulation mode is switched to Modcod i-1 ; Otherwise, maintain Modcod i constant.

[0055] The inter-satellite communication method for high-dynamic terminals of the present invention simplifies the inter-satellite communication process while ensuring the continuity and reliability of inter-satellite communication, and adopts an adaptive coding modulation method in the uplink to achieve rapid inter-satellite switching and efficient communication of high-dynamic terminals in satellite networking scenarios.

[0056] Although the present invention has been disclosed as a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the technical content disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for inter-satellite communication of highly dynamic terminals, characterized in that: include: The satellite has two-way communication with the terminal and the terminal control station; The satellite forwards the terminal service information to the terminal control station, and the satellite forwards the terminal control station preset information and signaling information to the terminal; Based on the preset information and signaling information, the terminal dynamically determines whether to initiate an inter-satellite handover; If inter-satellite switching is required, the terminal sends an inter-satellite switching request signal and forwards it to the destination satellite via the inter-satellite link; After the destination satellite performs user authentication and authorization, it allocates and reserves resources for the terminal and sends signaling information to the terminal; The terminal changes parameters according to the signaling information content to achieve communication with the destination satellite. The destination satellite forwards the terminal business information to the terminal control station. At the same time, the terminal status information is updated and sent to the terminal control station to complete the entire inter-satellite communication process.

2. The inter-satellite communication method for a high-dynamic terminal according to claim 1, characterized in that: The satellite and the terminal and the terminal control station implement two-way communication including inter-satellite communication of satellite downlink and inter-satellite communication of satellite uplink; The inter-satellite communication of the satellite downlink adopts a fixed allocation mode, that is, each satellite beam on the terminal operation path reserves downlink resources in advance to ensure communication with the terminal; The inter-satellite communication of the satellite uplink adopts a dynamic access mode, that is, each satellite beam on the terminal's operating path dynamically allocates uplink resources to communicate with the terminal according to the current satellite resource usage.

3. The inter-satellite communication method for a high dynamic terminal according to claim 1 or 2, characterized in that: The terminal predicts the downlink reception signal-to-noise ratio for a subsequent period of time according to the preset information and signaling information, and determines whether inter-satellite switching is required; If inter-satellite switching is required, the terminal selects and determines the destination satellite for the inter-satellite switching, and sends an inter-satellite switching request signal to the currently connected satellite through the uplink; Otherwise, no inter-satellite switching is performed and the original uplink and downlink communication links are maintained.

4. The inter-satellite communication method for a high-dynamic terminal according to claim 1 or 2, characterized in that: The preset information includes satellite ephemeris, satellite beam and downlink parameter information; the signaling information includes uplink parameter information and uplink receiving signal-to-noise ratio.

5. The inter-satellite communication method for a high-dynamic terminal according to claim 1 or 2, characterized in that: The specific steps include: (1) The terminal control station sends preset information to the terminal via satellite forwarding; (2) The terminal obtains information such as satellite ephemeris, satellite beam, and downlink parameters through the preset information forwarded by the satellite downlink; The terminal obtains uplink parameter information and uplink receiving signal-to-noise ratio through the signaling information sent by the satellite downlink; (3) The terminal uses machine learning and other methods to dynamically predict the downlink received signal-to-noise ratio for a period of time based on its own position, received downlink signal strength, and known satellite ephemeris and satellite beam information, and uses this to determine whether inter-satellite handover is required; (4) If inter-satellite switching is required, the terminal selects and determines the target satellite for the inter-satellite switching, and sends an inter-satellite switching request signal to the currently connected satellite via the uplink; Otherwise, no inter-satellite switching is performed and the original uplink and downlink communication links are maintained; (5) After receiving the inter-satellite handover request signal, the currently connected satellite forwards the inter-satellite handover request to the destination satellite through the inter-satellite link; (6) After receiving the inter-satellite handover request, the destination satellite performs user authentication and authorization, allocates and reserves uplink resources for the terminal, and sends signaling information to the terminal via the downlink; (7) After sending the inter-satellite handover request signal, the terminal uses the downlink parameters of the destination satellite for communication. After receiving the signaling information sent by the destination satellite downlink, the terminal changes the uplink parameters according to the signaling information content to achieve uplink communication with the destination satellite; (8) After receiving the uplink signal from the terminal, the destination satellite forwards the terminal service information to the terminal control station. At the same time, the terminal status information is updated and sent to the terminal control station, thus completing the entire inter-satellite communication process.

6. The inter-satellite communication method for a high-dynamic terminal according to claim 1 or 2, characterized in that: When initiating inter-satellite handover, the adaptive coding and modulation mode is also switched, including: In the uplink design, according to the requirements of uplink minimum system margin, n coding modulation schemes with different bit error rate thresholds are selected to form a set, and arranged from small to large according to the bit error rate threshold as the alternative uplink coding modulation schemes, denoted as {Modcod1, Modcod2, …Modcod n }; Set the upshift threshold L up and downshift threshold L down , then corresponding to n coding modulation modes, there is a set of upshift thresholds Downshift threshold set When the uplink coding modulation mode adopts Modcod i , i = 1, 2, 3...n, when the uplink receive signal-to-noise ratio increases and is greater than When the uplink coding modulation mode is switched to Modcod i+1 ; When the uplink coding modulation mode adopts Modcod i , the predicted uplink received signal-to-noise ratio will decrease and be less than When the uplink coding modulation mode is switched to Modcod i-1 ; Otherwise, maintain Modcod i constant.

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