A cross-satellite communication method for high dynamic terminals

Abstract

The application discloses a cross-satellite communication method for high dynamic terminals, which comprises the following steps: a satellite and a terminal and a terminal control station implement bidirectional communication; the satellite forwards terminal service information to the terminal control station, and the satellite forwards preset information and signaling information of the terminal control station to the terminal; according to the preset information and the signaling information, the terminal dynamically judges whether cross-satellite switching needs to be initiated; if cross-satellite switching needs to be performed, 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 the 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. Under the premise of ensuring continuous and reliable cross-satellite communication, the application simplifies the cross-satellite communication process, and adopts an adaptive coding modulation mode in an uplink, thereby realizing high dynamic terminal cross-satellite fast switching and efficient communication in a satellite networking scene.

Description

Technical Field

[0001] This invention relates to a cross-satellite communication method for highly dynamic terminals, belonging to the field of satellite communication. It can be used for cross-satellite communication of highly dynamic terminals in satellite constellation networking scenarios, realizing continuous and reliable communication of highly dynamic terminals. Background Technology

[0002] With the development of satellite communication, satellite communication systems based on single high-orbit satellites can no longer meet user needs. Satellite communication systems are rapidly shifting towards multi-satellite networking and satellite constellation networking. Given the topological changes inherent in satellite constellations and the high-speed movement characteristics of highly dynamic terminals, single satellite beams and single satellites can no longer meet the continuous communication requirements of these terminals, thus creating a demand for inter-satellite communication. At the same time, traditional inter-satellite communication schemes have complex interaction processes and long switching times, making them unsuitable for the rapid switching requirements of highly dynamic terminals. Therefore, it is urgent to design inter-satellite communication schemes specifically for the unique needs of highly dynamic terminals to achieve continuous and reliable communication services. Summary of the Invention

[0003] This invention proposes a cross-satellite communication method for highly dynamic terminals. It adopts a simplified cross-satellite communication process and achieves rapid cross-satellite switching and efficient communication for highly dynamic terminals while ensuring continuous and reliable communication.

[0004] The technical solution of this invention is:

[0005] A cross-satellite communication method for highly dynamic terminals, comprising:

[0006] The satellite communicates bidirectionally with both the terminal and the terminal control station.

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

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

[0009] If a cross-satellite handover is required, the terminal sends a cross-satellite handover request signal and forwards it to the target satellite via the inter-satellite link.

[0010] After the target 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 its parameters according to the signaling information to achieve communication with the target satellite. The target satellite forwards the terminal's service information to the terminal control station. At the same time, it updates the terminal's status information and sends it to the terminal control station, completing the entire inter-satellite communication process.

[0012] Optionally, the two-way communication between the satellite and the terminal and the terminal control station includes cross-satellite communication in the satellite downlink and cross-satellite communication in the satellite uplink.

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

[0014] The satellite uplink cross-satellite communication 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 based on the current satellite resource usage.

[0015] Optionally, the terminal predicts the downlink received signal-to-noise ratio for a subsequent period of time based on preset information and signaling information, and determines whether cross-satellite handover is required.

[0016] If a cross-satellite handover is required, the terminal selects and determines the target satellite for the handover and sends a cross-satellite handover request signal to the currently accessed satellite via the uplink; otherwise, a cross-satellite handover 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 received signal-to-noise ratio.

[0018] Optional, specifically including the following steps:

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

[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 received 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 signal-to-noise ratio for a period of time based on its own location, the strength of the received downlink signal, and the known satellite ephemeris and satellite beam information, and uses this to determine whether a cross-satellite handover is needed.

[0022] (4) If a cross-satellite handover is required, the terminal selects and determines the target satellite for the cross-satellite handover and sends a cross-satellite handover request signal to the currently accessed satellite via the uplink; otherwise, no cross-satellite handover is performed and the original uplink and downlink communication links are maintained.

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

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

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

[0026] (8) After receiving the uplink signal from the terminal, the target satellite forwards the terminal's service information to the terminal control station. At the same time, it updates the terminal's status information and sends it to the terminal control station, thus completing the entire inter-satellite communication process.

[0027] Optionally, while initiating the cross-satellite handover, an adaptive coding and modulation scheme switch may also be performed, specifically including:

[0028] In uplink design, based on requirements such as minimum system margin, n coding and modulation schemes with different bit error rate thresholds are selected to form a set, arranged in ascending order of bit error rate threshold, as candidate uplink coding and modulation schemes, denoted as {Modcod1, Modcod2, ..., Modcod...}. n};

[0029] Set the upshift threshold L up and downshift threshold L down For each of the n coding and modulation schemes, there is a set of upsampling thresholds. Downshift threshold set

[0030] When the uplink coding and modulation scheme adopts Modcod i Let i = 1, 2, 3...n. When the uplink received signal-to-noise ratio increases and is greater than... At that time, the uplink coding and modulation scheme will be switched to Modcod. i+1 When the uplink coding and modulation method adopts Modcod i The predicted uplink received signal-to-noise ratio will decrease and be less than [a certain value] in the subsequent period. At that time, the uplink coding and modulation scheme will be switched to Modcod. i-1 Otherwise, maintain Modcod i constant.

[0031] The advantages of this invention compared to the prior art are:

[0032] The cross-satellite communication method for highly dynamic terminals of the present invention simplifies the cross-satellite communication process while ensuring continuous and reliable cross-satellite communication, and adopts an adaptive coding and modulation method in the uplink to realize fast cross-satellite switching and efficient communication of highly dynamic terminals in satellite networking scenarios. Attached Figure Description

[0033] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0034] Figure 1 A flowchart of cross-satellite communication process for high-dynamic terminals;

[0035] Figure 2 A flowchart illustrating the uplink coding and modulation scheme switching process for high-dynamic terminals. Detailed Implementation

[0036] The following detailed description of the present invention is exemplary and not intended to limit the scope of the invention. Based on the embodiments of the present invention, all non-inventory modifications made by those skilled in the art without departing from the present invention should be considered within the scope of protection of the present invention.

[0037] This invention discloses the overall architecture of a cross-satellite communication method for highly dynamic terminals in a satellite networking scenario, including: satellite, terminal, and terminal control station.

[0038] The satellite enables two-way communication with the terminal and with the terminal control station; it dynamically allocates uplink resources based on the inter-satellite handover request signal sent by the terminal; it forwards the terminal's service information to the terminal control station and forwards the terminal control station's preset information to the terminal; and it forwards the inter-satellite handover request signal to the destination satellite through the inter-satellite link.

[0039] The terminal enables two-way communication with the satellite and dynamically determines whether to initiate cross-satellite handover and uplink coding and modulation mode switching.

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

[0041] The high-dynamic terminal inter-satellite communication process of this invention is described in [link to invention]. Figure 1 For the uplink coding and modulation method switching process of high dynamic terminals, see [link to relevant documentation]. Figure 2In practical applications, satellite downlink inter-satellite communication adopts a fixed allocation mode, meaning that each satellite beam in the terminal's operating path reserves downlink resources in advance to ensure communication with the terminal. Satellite uplink inter-satellite communication adopts a dynamic access mode, meaning that each satellite beam in the terminal's operating path dynamically allocates uplink resources to communicate with the terminal based on current satellite resource availability. In particular, the satellite uplink also employs an adaptive coding and modulation scheme, allowing the terminal to dynamically change its coding and modulation scheme based on the current uplink margin, thereby further improving the uplink communication rate.

[0042] To avoid loss of generality, the following description assumes a system with two satellites, one terminal, and one terminal control station, illustrating the specific cross-satellite handover process.

[0043] High-dynamic terminal cross-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 beams, downlink parameters, and other information through the preset information forwarded by the downlink of satellite 1. The terminal obtains uplink parameter information and uplink received signal-to-noise ratio through the signaling information sent by the downlink of satellite 1.

[0046] (3) Based on its own location, the downlink signal strength of satellite 1, and all known satellite ephemeris and satellite beam information, the terminal uses machine learning and other methods to dynamically predict the downlink signal-to-noise ratio of satellite 1 and satellite 2 in the future, and uses this to determine whether cross-satellite handover is necessary.

[0047] (4) If a cross-satellite handover to satellite 2 is required, the terminal shall send a cross-satellite handover request signal to satellite 1 via the uplink. Otherwise, no cross-satellite handover shall be performed, and the original uplink and downlink communication links shall be maintained.

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

[0049] (6) After receiving the cross-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 cross-satellite handover request signal, the terminal uses the downlink parameters of satellite 2 for communication. After receiving the signaling information sent from the downlink of satellite 2, the terminal changes the uplink parameters according to the content of the signaling information to realize 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, it updates the terminal status information and sends it to the terminal control station, thus completing the entire inter-satellite communication process.

[0052] In the set of coding modulation schemes {Modcod1, Modcod2, ... Modcod n}, Upgrade Threshold Set Downshift threshold set Among them, the upshift threshold L up and downshift threshold L down The selection of the uplink coding and modulation scheme can employ existing methods such as shift thresholds to ensure the reliability of the communication link. After the setting is completed according to the method of this invention, the high-dynamic terminal uplink coding and modulation scheme switching process is as follows:

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

[0054] (2) When the uplink coding and modulation method of satellite 1 adopts Modcod i For i = 1, 2, 3...n, the predicted uplink received signal-to-noise ratio will increase and be greater than [value missing] in the subsequent period. At that time, the uplink coding and modulation scheme will be switched to Modcod. i+1 When Satellite 1 uses Modcod uplink coding and modulation... i The predicted uplink received signal-to-noise ratio will decrease and be less than [a certain value] in the subsequent period. At that time, the uplink coding and modulation scheme will be switched to Modcod. i-1 Otherwise, maintain Modcod i constant.

[0055] The cross-satellite communication method for highly dynamic terminals of the present invention simplifies the cross-satellite communication process while ensuring continuous and reliable cross-satellite communication, and adopts an adaptive coding and modulation method in the uplink to realize fast cross-satellite switching and efficient communication of highly dynamic terminals in satellite networking scenarios.

[0056] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make possible variations and modifications to the technical solutions of the present invention based on the disclosed technical content without departing from the spirit and scope of the invention. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the present invention.

Claims

1. A cross-satellite communication method for highly dynamic terminals, characterized in that, include: The satellite communicates bidirectionally with both the terminal and the terminal control station. The satellite forwards terminal service information to the terminal control station, and the satellite forwards the terminal control station's preset information and signaling information to the terminal. Based on preset information and signaling information, the terminal dynamically determines whether to initiate a cross-satellite handover; If a cross-satellite handover is required, the terminal sends a cross-satellite handover request signal and forwards it to the target satellite via the inter-satellite link. After the target satellite performs user authentication and authorization, it allocates and reserves resources for the terminal and sends signaling information to the terminal. The terminal modifies its parameters according to the signaling information to achieve communication with the target satellite. The target satellite forwards the terminal's service information to the terminal control station. At the same time, the terminal updates its status information and sends it to the terminal control station, completing the entire inter-satellite communication process. The aforementioned two-way communication between the satellite and the terminal and the terminal control station includes cross-satellite communication in the downlink and cross-satellite communication in the uplink. Cross-satellite communication in the downlink adopts a fixed allocation mode, that is, each satellite beam on the terminal's operating path reserves downlink resources in advance to ensure communication with the terminal. Cross-satellite communication in the 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 based on the current satellite resource usage. While initiating the cross-satellite handover, an adaptive coding and modulation scheme switch is also performed, specifically including: In uplink design, based on the minimum system margin of the uplink, n coding and modulation schemes with different bit error rate thresholds are selected to form a set, and arranged in ascending order of bit error rate threshold as candidate schemes for uplink coding and modulation. This set is denoted as . ; Set the upgrade threshold and downshift threshold For each of the n coding and modulation schemes, there is a set of upsampling thresholds. Downshift threshold set ; When the uplink coding and modulation method adopts Let i = 1, 2, 3...n. When the uplink received signal-to-noise ratio increases and is greater than... At that time, the uplink coding and modulation scheme will be switched to When the uplink coding and modulation method adopts The predicted uplink received signal-to-noise ratio will decrease and be less than [a certain value] in the subsequent period. At that time, the uplink coding and modulation scheme will be switched to Otherwise, maintain constant.

2. The inter-satellite communication method for highly dynamic terminals according to claim 1, characterized in that, The terminal predicts the downlink received signal-to-noise ratio for a subsequent period of time based on preset information and signaling information, and determines whether cross-satellite handover is required. If a cross-satellite handover is required, the terminal selects and determines the target satellite for the handover and sends a cross-satellite handover request signal to the currently accessed satellite via the uplink. Otherwise, cross-satellite handover will not be performed, and the original uplink and downlink communication links will be maintained.

3. The inter-satellite communication method for highly dynamic terminals 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 received signal-to-noise ratio.

4. The inter-satellite communication method for highly dynamic terminals according to claim 1 or 2, characterized in that, Specifically, the following steps are included: (1) The terminal control station sends preset information to the terminal via satellite relay; (2) The terminal obtains satellite ephemeris, satellite beam and downlink parameters through the preset information forwarded by the satellite downlink; the terminal obtains uplink parameter information and uplink received signal-to-noise ratio through the signaling information sent by the satellite downlink. (3) The terminal uses machine learning to dynamically predict the downlink signal-to-noise ratio for a period of time based on its own location, the strength of the received downlink signal, and the known satellite ephemeris and satellite beam information, and uses this to determine whether a cross-satellite handover is needed. (4) If a cross-satellite handover is required, the terminal selects and determines the target satellite for the cross-satellite handover and sends a cross-satellite handover request signal to the currently accessed satellite via the uplink; Otherwise, no cross-satellite handover will be performed, and the original uplink and downlink communication links will be maintained; (5) After receiving the inter-satellite handover request signal, the currently accessing satellite forwards the inter-satellite handover request to the destination satellite through the inter-satellite link; (6) After receiving the cross-satellite handover request, the target satellite performs user authentication and authorization, allocates and reserves uplink resources for the terminal, and sends signaling information to the terminal through the downlink; (7) After sending the cross-satellite handover request signal, the terminal uses the downlink parameters of the destination satellite for communication; After receiving the signaling information from the downlink of the target satellite, the terminal modifies the uplink parameters according to the content of the signaling information to realize communication between the uplink and the target satellite; (8) After the target satellite receives the uplink signal from the terminal, it forwards the terminal service information to the terminal control station; at the same time, it updates the terminal status information and sends it to the terminal control station, thereby completing the entire inter-satellite communication process.

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