Star information path autonomous planning method for giant constellation

Abstract

The application discloses a method for on-board information path autonomous planning for a mega constellation, and belongs to the technical field of mega constellation autonomous operation.The application aims at the problem that limited ground station resources cannot guarantee high real-time response requirements of a mega constellation in view of limited on-board processing capacity.The method comprises grid path initial planning, satellite neighborhood resource sensing and on-board information path autonomous planning; the global fixed grid unit is established in the grid path initial planning, and a static grid path for assisting on-board planning is provided; the satellite neighborhood resource sensing applies constellation topology division and operation law, so that the satellite can quickly predict neighborhood node information; the on-board information path autonomous planning matches the grid planning path by using satellite neighborhood node resources, and decides the next satellite node for forwarding information.The application can realize autonomous and efficient interconnection of the constellation, and can forward task information through on-board autonomous sensing, rapid decision and forwarding.

Description

Technical Field

[0001] This invention relates to an autonomous planning method for on-board information paths for the Giant constellation, belonging to the field of autonomous operation technology for mega-constellations. Background Technology

[0002] The development of giant low-Earth orbit satellite constellations has effectively expanded the space for global interconnection. By accessing globally covered satellite communication networks, they can provide rapid interconnection responses to remote areas and disaster relief efforts, regardless of geographical limitations. Currently, the Starlink constellation has conducted experiments on inter-satellite laser communication. Communication via inter-satellite links will replace traditional ground station control and become the main means of constellation interconnection.

[0003] The onboard information path planning method determines the information response performance of the giant low-Earth orbit constellation. Due to the large number of satellites in this constellation, their high operational dynamism, and short transit times, relying on limited ground station resources makes it difficult to guarantee high real-time response requirements when facing multiple global missions and latency-sensitive needs. Furthermore, due to limited onboard processing power, the method of recursively calculating the optimal paths for thousands of satellites becomes impractical when global satellite information cannot be stored. Therefore, an autonomous information path planning scheme is needed under the limited onboard processing power, enabling satellites to have information forwarding and processing capabilities based on neighborhood resource awareness, achieving autonomous and efficient interconnection of the constellation.

[0004] Current mega-constellation path planning typically involves further optimizing the path planning algorithm and inter-satellite mission offloading methods under the premise of known global orbital information, in order to achieve the best performance of low global latency and load balancing. However, there are no effective theoretical results for autonomous constellation planning under the background of limited on-board processing capabilities. Summary of the Invention

[0005] To address the problem that limited onboard processing capabilities and the inability of limited ground station resources to guarantee the high real-time response requirements of the Giants constellation, this invention provides an autonomous onboard information path planning method for the Giants constellation.

[0006] The present invention provides an autonomous on-board information path planning method for the constellation Giants, comprising:

[0007] Based on the relative motion and communication capabilities of the satellites, the satellites in the constellation Gigantopithecus are divided into multiple constellation topologies. Based on the coverage of the constellation topologies over the ground, a fixed Earth grid with an alternating latitudinal layout is established. Each grid cell in the fixed Earth grid is encoded according to its latitude and longitude coordinates. Then, the weights of adjacent grid cells are set to obtain the weight matrix of the fixed Earth grid.

[0008] Match the corresponding task initiation grid cell and task target grid cell to the task initiation point and task target point. Based on the grid cell encoding and weight matrix, use Dijkstra's algorithm to calculate the shortest path from the task initiation grid cell to the task target grid cell, and obtain the grid path matrix of all grid cells passed through.

[0009] For each constellation topology, satellite neighborhood resources are sensed based on the distance to the central satellite of adjacent constellation topologies and communication capabilities, and the neighborhood topology resource set of each constellation topology is determined. The neighborhood topology resource set includes a long-term visible topology resource set and an intermittently visible topology resource set.

[0010] The system transmits mission information and a grid path matrix to the optimal window satellite. Based on the grid path matrix, the optimal window satellite determines the nearest and shortest path neighboring satellite in the corresponding neighborhood topology resource set and transmits the mission information and grid path matrix to the neighboring satellite. The neighboring satellite then determines the corresponding intermediate relay satellites in sequence based on the grid path matrix and the corresponding neighborhood topology resource set. The intermediate relay satellites then transmit mission information to the mission target point, thereby achieving mission information transmission under the autonomous planning of on-board information paths.

[0011] According to the autonomous on-board information path planning method for the Giants constellation based on the present invention, the rules for establishing the Earth fixed grid are as follows:

[0012] The grid cells are matched to the coverage area of ​​the constellation topology; and the grid cells are squares in the Mercator projection, with a side length of l. M'N' satisfy:

[0013] l M'N' =2R E arcsin(r topo / r),

[0014] In the formula R E r is the Earth's radius. topo Let r be the topological radius of the constellation topology, and r be the orbital radius of the circular orbiting satellite in the constellation Gigantopithecus.

[0015] The method for autonomous on-board information path planning for the Giant Pilates constellation according to the present invention obtains the grid cell encoding as follows:

[0016] The layout of a grid cell in global geography is described by the longitude and latitude coordinates of its four vertices. Let the latitude coordinates of the four vertices be [lat1,lat1+lat0,lat1+lat0,lat1], and the longitude coordinates be [lon1,lon1,lon1+lon0,lon1+lon0]. Then, the grid cell code AB is obtained.

[0017] A=180 / lat0-(lat1+90) / lat0,

[0018]

[0019] Where lat1 is the latitude value of the bottom left and bottom right vertices of the grid cell, lat1+lat0 is the latitude value of the top left and top right vertices of the grid cell, and lat0 is the latitude span of the grid cell; lon1 is the longitude of the bottom left and top left vertices of the grid cell, lon1+lon0 is the longitude value of the top right and bottom right vertices of the grid cell, and lon0 is the longitude span of the grid cell; Δλ is the longitude offset of adjacent rows of grid cells.

[0020] According to the autonomous on-board information path planning method for the Giant Pisces constellation of the present invention, the method for obtaining the weight matrix of the Earth fixed grid is as follows:

[0021] In a fixed Earth grid, two geographically adjacent grid cells are considered adjacent, represented by 1; otherwise, they are represented by 0. An adjacency matrix is ​​constructed. The weights of adjacent grid cells are distributed in a gradient from non-polar to polar regions. The vertical weight gradient matrix Q of the fixed Earth grid is defined as follows:

[0022] Q = [q1, q2, q3, ... q n ],

[0023] In the formula, n is the set number of vertical weight gradient layers:

[0024]

[0025]

[0026] In the formula q j Let lat be the vertical weight of the grid cell at the j-th gradient. α Let lat be the latitude of the center point of the current grid cell at the j-th gradient. β The latitude of the center point of the adjacent grid cells of the current grid cell;

[0027] Let the horizontal weight gradient matrix P of the Earth fixed grid be:

[0028] P = [p1, p2, p3, ... p n ],

[0029] The horizontal weight p of the grid cell at the j-th gradient j for:

[0030]

[0031] The lower the weight, the greater the probability that the connection path between two adjacent grid cells will be selected as the shortest path jump;

[0032] The weight matrix of the Earth fixed grid is constructed by the vertical weight gradient matrix Q and the horizontal weight gradient matrix P.

[0033] According to the autonomous planning method for on-board information paths in the constellation Giants of the present invention, the grid path matrix for all traversed grid cells is represented as G:

[0034] G = [g1, g2, g3, ..., g m ],

[0035] The i-th grid cell in the shortest path is encoded as g. i :

[0036]

[0037] In the formula Let λ represent the latitude of the center point of the i-th grid cell in the shortest path. i This represents the longitude of the center point of the i-th grid cell in the shortest path; m is the total number of grid cells in the shortest path.

[0038] According to the autonomous on-board information path planning method for the Giants constellation of the present invention, the long-term visible topology resource set is a constellation topology set that can stably communicate with the current constellation topology;

[0039] The set of intermittently visible topological resources is determined by spherical triangulation that intersects the satellite orbits of satellites in the current constellation topology.

[0040] According to the autonomous on-board information path planning method for the Giants constellation of the present invention, the constellation topology in the long-term visible topology resource set and the satellites in the current constellation topology can be interconnected.

[0041] All constellation topologies are set to star topologies, with the distance from the topological center star of the current constellation topology set to 2r. topo The star constellation topology containing all other topological central stars within the range constitutes a long-term visible set of topological resources.

[0042] The long-term visible topological resource set is represented as V E :

[0043]

[0044] In the formula A star constellation topology within a long-term visible topological resource set. Central Star Located at position y' of orbit x', For the current constellation topology The central star, current constellation topology Central Star Located at position y on orbit x, For the central star and the central star The angle between the line connecting the Earth's center and the Earth's core; θ max The geocentric angle corresponding to the maximum visible distance between the two central stars is given. The topological central stars of all star-shaped constellations in the constellation Giants are evenly distributed on I orbits, with B topological central stars on each orbit.

[0045]

[0046] In the formula, H is the thickness of the atmosphere.

[0047] According to the autonomous on-board information path planning method for the Giants constellation of the present invention, the method for obtaining the set of intermittently visible topological resources is as follows:

[0048] Construct a spherical triangle Δabc formed by the intersection of two orbits x1 and x2 with the equator from among I orbits. Let the geocenter be point O. Use the cosine theorem for spherical triangles to obtain the constellation topology. The time when it intersects with the x2th orbit is t:

[0049] cos(∠bOc)=-cos 2 (i0)+sin 2 (i0)·cos(180-(Ω x1 -Ω x2 )),

[0050] cos(180-(Ω x1 -Ω x2 ))=cos 2 (θ t )+sin 2 (θ t cos(∠bOc),

[0051] f = θ t -ω,

[0052]

[0053] In the formula, ∠bOc is the spherical angle corresponding to the equatorial arc, i0 is the orbital inclination angle of the two orbits x1 and x2, and Ω x1 Let Ω be the right ascension of the ascending node of orbit x1. x2 Let θ be the right ascension of the ascending node of orbit x2. t constellation topology on orbit x1 When the central star intersects with orbit x2 The orbital angle of the central star, f is the orbital angle of the central star. The current true anomaly angle, ω is the central star. The perigee argument, T is the central star. The orbital period, f0 is the central star The initial true anterior angle;

[0054] Then the current constellation topology will be... The set of intermittently visible topological resources at time t is represented as V. IN :

[0055]

[0056] In the formula For the constellation topology in the intermittently visible topological resource set, constellation topology The central star is located at position b in orbit x2, and γ is the geocentric angle constraint corresponding to the allowable stable reverse communication distance:

[0057]

[0058] According to the autonomous on-board information path planning method for the Giants constellation of the present invention, if the grid cell corresponding to the satellite in the optimal window is in the shortest path from the mission initiation grid cell to the mission target grid cell, then in the grid path matrix G = [g1, g2, g3, ..., g m ] Remove the grid cell code g1 corresponding to the best window satellite, and obtain the remaining grid path matrix G1 = [g2, g3, ..., g m Otherwise, the optimal window satellite determines the nearest neighboring satellite to the shortest path in the corresponding neighborhood topology resource set based on the grid path matrix G, and forwards the mission information and grid path matrix to the grid cell corresponding to the neighboring satellite until the neighboring satellite is in the shortest path, in the grid path matrix G = [g1, g2, g3, ..., g m ] Remove the grid cell code g1 corresponding to the best window satellite, and obtain the remaining grid path matrix G1 = [g2, g3, ..., g m ].

[0059] According to the autonomous on-board information path planning method for the Giants constellation of the present invention, during the process of neighboring satellites sequentially determining intermediate transfer satellites, the same judgment process as that for the optimal window satellite and the corresponding neighboring satellite is performed on the neighboring satellites and intermediate transfer satellites; the remaining grid path matrix G is obtained sequentially. w =[g w+1 ,g w+2 ,…,g m ], where w is the number of times the current grid cell code is deleted;

[0060] After each intermediate transfer satellite is determined, if the current remaining grid path matrix Gw satisfy Then continue to transmit satellite mission information and the current remaining grid path matrix G to the center. w Until the task information reaches the task target grid cell g m The corresponding optimal downlink intermediate satellite transmits the mission information to the mission target point, and the on-board decision-making and forwarding mission ends.

[0061] The beneficial effects of this invention are as follows: The method of this invention performs autonomous on-board information path planning based on initial grid path planning and satellite neighborhood resource perception. Initial grid path planning provides static grid paths to assist on-board planning, while satellite neighborhood resource perception uses constellation topology partitioning and operational rules to predict neighborhood node information. On-board information path planning utilizes satellite neighborhood node resources to match the grid-planned path and decides the satellite node for the next information relay. This invention enables autonomous and efficient constellation interconnection, transforming the existing information path planning process, which requires complex global orbital recursive decision-making, into a process of autonomous on-board perception, rapid decision-making, and relaying. This invention provides an effective solution for achieving high-speed transmission of information between giant constellations. Attached Figure Description

[0062] Figure 1 This is an overall flowchart of the autonomous on-board information path planning method for the Giants constellation described in this invention;

[0063] Figure 2 This is a schematic diagram of the structure and coding of the Earth's fixed grid; the code in the diagram is AB, representing the specific value.

[0064] Figure 3 This is a schematic diagram of the grid cell layout and adjacency gradient settings in a fixed Earth grid; p in the diagram k Let be the horizontal weight of the grid cell at the k-th gradient;

[0065] Figure 4 This is a flowchart illustrating the specific implementation of the autonomous on-board information path planning of this invention. Detailed Implementation

[0066] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0067] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0068] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0069] Specific Implementation Method 1: Combination Figures 1 to 4 As shown, this invention provides an autonomous on-board information path planning method for the constellation Giants, including:

[0070] Based on the relative motion and communication capabilities of the satellites, the satellites in the constellation Gigantopithecus are divided into multiple constellation topologies. Based on the coverage of the constellation topologies over the ground, a fixed Earth grid with an alternating latitudinal layout is established. Each grid cell in the fixed Earth grid is encoded according to its latitude and longitude coordinates. Then, the weights of adjacent grid cells are set to obtain the weight matrix of the fixed Earth grid.

[0071] Match the corresponding task initiation grid cell and task target grid cell to the task initiation point and task target point. Based on the grid cell encoding and weight matrix, use Dijkstra's algorithm to calculate the shortest path from the task initiation grid cell to the task target grid cell, and obtain the grid path matrix of all grid cells passed through.

[0072] For each constellation topology, satellite neighborhood resources are sensed based on the distance to the central satellite of adjacent constellation topologies and communication capabilities, and the neighborhood topology resource set of each constellation topology is determined. The neighborhood topology resource set includes a long-term visible topology resource set and an intermittently visible topology resource set.

[0073] The system transmits mission information and a grid path matrix to the optimal window satellite. Based on the grid path matrix, the optimal window satellite determines the nearest and shortest path neighboring satellite in the corresponding neighborhood topology resource set and transmits the mission information and grid path matrix to the neighboring satellite. The neighboring satellite then determines the corresponding intermediate relay satellites in sequence based on the grid path matrix and the corresponding neighborhood topology resource set. The intermediate relay satellites then transmit mission information to the mission target point, thereby achieving mission information transmission under the autonomous planning of on-board information paths.

[0074] This implementation method includes three steps: initial grid path planning, satellite neighborhood resource perception, and autonomous on-board information path planning. In the initial grid path planning, a fixed Earth grid is established as a static grid path to assist on-board planning. The satellite neighborhood resource perception method enables the satellite to quickly predict neighborhood node information. Finally, the satellite neighborhood node resources are used to match the grid planning path and decide the satellite node for the next information relay, thus realizing the autonomous planning of the on-board information path.

[0075] In the initial grid path planning, the shortest path jump method is determined by configuring a fixed Earth grid; in the grid configuration, the distribution of geographic grid units and the weights of adjacent paths are configured in combination with the dynamic characteristics of the constellation; the shortest path jump is based on the task initiation and target location to quickly match the grid starting point and the shortest path for grid jump; thus, a static grid path planning scheme that can provide auxiliary on-board autonomous decision-making reference is obtained.

[0076] Furthermore, combined with Figure 2 and Figure 3 As shown, the rules for establishing a fixed Earth grid are as follows:

[0077] The grid cells are matched to the coverage area of ​​the constellation topology; and the grid cells are squares in the Mercator projection, with a side length of l. M'N' satisfy:

[0078] l M'N' =2R E arcsin(r topo / r),

[0079] In the formula R E r is the Earth's radius. topo Let r be the topological radius of the constellation topology, and r be the orbital radius of the circular orbiting satellite in the constellation Gigantopithecus.

[0080] As an example, combined Figure 2 As shown, the method for obtaining the grid cell code is as follows:

[0081] The grid cells are staggered in the latitudinal direction to accommodate the operation of various inclined orbit constellations;

[0082] The layout of a grid cell in global geography is described by the longitude and latitude coordinates of its four vertices. Let the latitude coordinates of the four vertices be [lat1,lat1+lat0,lat1+lat0,lat1], and the longitude coordinates be [lon1,lon1,lon1+lon0,lon1+lon0]. Then, the grid cell code AB is obtained.

[0083] A=180 / lat0-(lat1+90) / lat0,

[0084]

[0085] Where lat1 is the latitude value of the bottom left and bottom right vertices of the grid cell, lat1+lat0 is the latitude value of the top left and top right vertices of the grid cell, and lat0 is the latitude span of the grid cell; lon1 is the longitude of the bottom left and top left vertices of the grid cell, lon1+lon0 is the longitude value of the top right and bottom right vertices of the grid cell, and lon0 is the longitude span of the grid cell; Δλ is the longitude offset of adjacent rows of grid cells.

[0086] Considering the connection between longitude -180° and 180°, when B≤0, B=360 / lon0+B.

[0087] Furthermore, the method for obtaining the weight matrix of the Earth's fixed grid is as follows:

[0088] The edge formed by connecting the center points of two grid cells represents the adjacency relationship between the two grids. Weights are set for this edge to support subsequent path planning. Considering that the stability of inter-satellite links decreases as satellites approach the polar region, path planning based on network communication stability tends to concentrate information jumps in non-polar locations. Therefore, the weights of grid adjacency are set to have a gradient distribution in different latitude zones.

[0089] In a fixed Earth grid, two geographically adjacent grid cells are considered adjacent, represented by 1; otherwise, they are represented by 0. An adjacency matrix is ​​constructed. The weights of adjacent grid cells are distributed in a gradient from non-polar to polar regions. The vertical weight gradient matrix Q of the fixed Earth grid is defined as follows:

[0090] Q = [q1, q2, q3, ... q n ],

[0091] In the formula, n is the set number of vertical weight gradient layers:

[0092]

[0093]

[0094] In the formula q j Let lat be the vertical weight of the grid cell at the j-th gradient. α Let lat be the latitude of the center point of the current grid cell at the j-th gradient. β The latitude of the center point of the adjacent grid cells of the current grid cell;

[0095] Let the horizontal weight gradient matrix P of the Earth fixed grid be:

[0096] P = [p1, p2, p3, ... p n ],

[0097] The horizontal weight p of the grid cell at the j-th gradientj for:

[0098]

[0099] The lower the weight, the greater the probability that the connection path between two adjacent grid cells will be selected as the shortest path jump;

[0100] The weight matrix of the Earth fixed grid is constructed by the vertical weight gradient matrix Q and the horizontal weight gradient matrix P.

[0101] In this embodiment, the grid path matrix of all passing grid cells is represented as G:

[0102] G = [g1, g2, g3, ..., g m ],

[0103] The i-th grid cell in the shortest path is encoded as g. i :

[0104]

[0105] In the formula Let λ represent the latitude of the center point of the i-th grid cell in the shortest path. i This represents the longitude of the center point of the i-th grid cell in the shortest path; m is the total number of grid cells in the shortest path.

[0106] In this embodiment, AB is the general format for grid cell encoding. Corresponding to a specific grid.

[0107] In this embodiment, the long-term visible topology resource set is a set of constellation topologies that can communicate stably with the current constellation topology; all satellites in the long-term visible topology resource set have relatively stable operational relationships, and other topologies that can communicate stably in any topological neighborhood can be quickly determined from the long-term visible topology resource set;

[0108] The set of intermittently visible topological resources is determined by spherical triangulation that intersects the satellite orbits of satellites in the current constellation topology.

[0109] By configuring long-term visible topological resource sets and intermittent visible topological resource sets, satellites can quickly perceive the communicable satellite resources in the vicinity, even when global information is unknown and onboard processing capabilities are limited.

[0110] In this embodiment, a uniformly distributed sub-management domain covering the entire constellation is constructed, and the sub-management domain is described in the form of a star constellation topology.

[0111] The constellation topology in the long-term visible topology resource set can communicate with the satellites in the current constellation topology;

[0112] All constellation topologies are set to star topologies, with the distance from the topological center star of the current constellation topology set to 2r. topo The star constellation topology containing all other topological central stars within the range constitutes a long-term visible set of topological resources.

[0113] The long-term visible topological resource set is represented as V E :

[0114]

[0115] In the formula A star constellation topology within a long-term visible topological resource set. Central Star Located at position y' of orbit x', For the current constellation topology The central star, current constellation topology Central Star Located at position y on orbit x, For the central star and the central star The angle between the line connecting the Earth's center and the Earth's core; θ max The geocentric angle corresponds to the maximum visible distance between the two central stars. In the constellation Giants, the topological central stars of all star types are uniformly distributed across I orbits, with B topological central stars in each orbit; the default is 2r. topo Satellites within the range can communicate with each other. If two central satellites can communicate, it is assumed that satellites within the two sub-topologies can communicate with each other.

[0116]

[0117] In the formula, H is the thickness of the atmosphere.

[0118] The method for obtaining the set of intermittently visible topological resources is as follows:

[0119] Based on the relative orbital patterns of satellites and orbital intersection characteristics, the set of intermittently visible topological resources V is calculated. IN First, construct a spherical triangle Δabc formed by the intersection of two orbits x1 and x2 with the equator from the I orbits. Let the geocenter be point O. Use the cosine theorem of spherical triangles to obtain the constellation topology. The time when it intersects with the x2th orbit is t:

[0120] cos(∠bOc)=-cos 2 (i0)+sin 2 (i0)·cos(180-(Ω x1 -Ω x2 )),

[0121] cos(180-(Ωx1 -Ω x2 ))=cos 2 (θ t )+sin 2 (θ t cos(∠bOc),

[0122] f = θ t -ω,

[0123]

[0124] In the formula, ∠bOc is the spherical angle corresponding to the equatorial arc, i0 is the orbital inclination angle of the two orbits x1 and x2, and Ω x1 Let Ω be the right ascension of the ascending node of orbit x1. x2 Let θ be the right ascension of the ascending node of orbit x2. t constellation topology on orbit x1 When the central star intersects with orbit x2 The orbital angle of the central star, f is the orbital angle of the central star. The current true anomaly angle, ω is the central star. The perigee argument, T is the central star. The orbital period, f0 is the central star The initial true anterior angle;

[0125] Then the current constellation topology will be... The set of intermittently visible topological resources at time t is represented as V. IN :

[0126]

[0127] In the formula For the constellation topology in the intermittently visible topological resource set, constellation topology The central star is located at position b in orbit x2, and γ is the geocentric angle constraint corresponding to the allowable stable reverse communication distance:

[0128]

[0129] Furthermore, the autonomous on-board information path planning consists of initial node matching, autonomous satellite forwarding decision-making, and terminal node convergence. Initial node matching combines a static grid path scheme, the mission initiation location, and the location of the nearest communicable satellite to match the satellite with the grid path, determining the subsequent forwarding direction. Autonomous satellite forwarding decision-making provides the next forwarding topology based on neighborhood resource information and grid path matching. Terminal node convergence determines whether the information has reached the target location, avoiding redundant decision-making at the terminal. Using this method, autonomous on-board information path planning can be achieved, enabling rapid interconnection and communication within a large constellation. Details are as follows:

[0130] Combination Figure 4 As shown, in this embodiment, if the grid cell corresponding to the satellite in the optimal window is in the shortest path from the mission initiation grid cell to the mission target grid cell, then in the grid path matrix G = [g1, g2, g3, ..., g m ] Remove the grid cell code g1 corresponding to the best window satellite, and obtain the remaining grid path matrix G1 = [g2, g3, ..., g m Otherwise, the optimal window satellite determines the nearest neighboring satellite to the shortest path in the corresponding neighborhood topology resource set based on the grid path matrix G, and forwards the mission information and grid path matrix to the grid cell corresponding to the neighboring satellite until the neighboring satellite is in the shortest path, in the grid path matrix G = [g1, g2, g3, ..., g m ] Remove the grid cell code g1 corresponding to the best window satellite, and obtain the remaining grid path matrix G1 = [g2, g3, ..., g m ].

[0131] During the process of sequentially determining intermediate transfer satellites from neighboring satellites, the same judgment process as that for the optimal window satellite and the corresponding neighboring satellites is performed on both the neighboring satellites and the intermediate transfer satellites; the remaining grid path matrix G is obtained sequentially. w =[g w+1 ,g w+2 ,…,g m ], where w is the number of times the current grid cell code is deleted;

[0132] After each intermediate transfer satellite is determined, if the current remaining grid path matrix G w satisfy Then continue to transmit satellite mission information and the current remaining grid path matrix G to the center. w Until the task information reaches the task target grid cell g m The corresponding optimal downlink intermediate satellite transmits the mission information to the mission target point, and the on-board decision-making and forwarding mission ends.

[0133] The following is combined with Figure 4 The specific implementation process of path planning is explained below:

[0134] (a) The ground station uploads mission information and static grid path scheme G = [g1, g2, g3, ..., g] to the satellite in the optimal window. m ];

[0135] (b) The satellite in the best window identifies whether it is currently in the shortest path scheme. If so, proceed to (d); otherwise, proceed to (c).

[0136] (c) The satellite in the optimal window forwards information to the satellite in the direction of the nearest grid in G, and the receiving satellite re-detects (b) conditions;

[0137] (d) The satellite deletes the portion of the grid path that has already been reached, resulting in G1 = [g2, g3, ..., g m ];

[0138] (e) If Based on the grid path direction and the neighborhood resources V = V E ∪V IN Perform matching and forward mission information and remaining node information G to the nearest neighboring satellite in the direction. w =[g w+1 ,g w+2 ,…,g m ];

[0139] (f) Determine if the current satellite node is offset from the grid path. If so, determine the positional relationship between the current grid and the corresponding grid in the initial path scheme, and perform path regression on the initial scheme until returning to the grid path G. w Inside;

[0140] (g) Update the remaining grid paths G w+1 If the end grid node is not reached, proceed to (e) for the next jump; otherwise, proceed to (h).

[0141] (h) Upon reaching the terminal network node, information is transmitted. If the satellite topology and the grid do not match perfectly, the topology closest to the terminal grid is selected and information is transmitted.

[0142] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A method for autonomous planning of on-board information paths for the constellation Giants, characterized in that... include, Based on the relative motion and communication capabilities of the satellites, the satellites in the constellation Gigantopithecus are divided into multiple constellation topologies. Based on the coverage of the constellation topologies over the ground, a fixed Earth grid with an alternating latitudinal layout is established. Each grid cell in the fixed Earth grid is encoded according to its latitude and longitude coordinates. Then, weights are assigned to the adjacent grid cells of each grid cell to obtain the weight matrix of the Earth fixed grid; Match the corresponding task initiation grid cell and task target grid cell to the task initiation point and task target point. Based on the grid cell encoding and weight matrix, use Dijkstra's algorithm to calculate the shortest path from the task initiation grid cell to the task target grid cell, and obtain the grid path matrix of all grid cells passed through. For each constellation topology, satellite neighborhood resources are sensed based on the distance to the central satellite of adjacent constellation topologies and communication capabilities, and the neighborhood topology resource set of each constellation topology is determined. The neighborhood topology resource set includes a long-term visible topology resource set and an intermittently visible topology resource set. The long-term visible topology resource set is the set of constellation topologies that can communicate stably with the current constellation topology; the intermittent visible topology resource set is determined by the spherical triangulation of the satellite orbits intersecting with those of satellites in the current constellation topology. The system transmits mission information and a grid path matrix to the optimal window satellite. Based on the grid path matrix, the optimal window satellite determines the nearest and shortest path neighboring satellite in the corresponding neighborhood topology resource set and transmits the mission information and grid path matrix to the neighboring satellite. The neighboring satellite then determines the corresponding intermediate relay satellites in sequence based on the grid path matrix and the corresponding neighborhood topology resource set. The intermediate relay satellites then transmit mission information to the mission target point, thereby achieving mission information transmission under the autonomous planning of on-board information paths.

2. The autonomous on-board information path planning method for the Giants constellation according to claim 1, characterized in that, The rules for establishing a fixed Earth grid are as follows: The grid cells are matched to the coverage area of ​​the constellation topology; and the grid cells are squares in the Mercator projection, with a side length of [missing information]. satisfy: ， In the formula R E For the Earth's radius, Let r be the topological radius of the constellation topology, and r be the orbital radius of the circular orbiting satellite in the constellation Gigantopithecus.

3. The autonomous on-board information path planning method for the Giants constellation according to claim 2, characterized in that, The method for obtaining the grid cell code is as follows: The layout of a grid cell in global geography is described by the longitude and latitude coordinates of its four vertices. The latitude coordinates of the four vertices of the grid cell are set as follows: The longitude coordinates of the four vertices are Then we get the grid cell code AB: ， ， in These are the latitude values ​​of the bottom left and bottom right vertices of the grid cell. These are the latitude values ​​of the top-left and top-right vertices of the grid cell. The latitudinal span of the grid unit; The longitudes of the bottom left and top left vertices of the grid cell. These are the longitude values ​​of the top-right and bottom-right vertices of the grid cell. For grid cell longitude span; This represents the longitude offset of adjacent grid cells.

4. The autonomous on-board information path planning method for the Giants constellation according to claim 3, characterized in that, The method for obtaining the weight matrix of the Earth fixed grid is as follows: In a fixed Earth grid, two geographically adjacent grid cells are considered adjacent (represented by 1), otherwise 0, and an adjacency matrix is ​​constructed. The weights of adjacent grid cells are then distributed in a gradient from non-polar to polar regions. A vertical weight gradient matrix for the fixed Earth grid is then defined. for: In the formula, n is the set number of vertical weight gradient layers: ， ； In the formula Let J be the vertical weight of the grid cell at the j-th gradient. Let the latitude of the center point of the current grid cell at the j-th gradient be denoted as . The latitude of the center point of the adjacent grid cells of the current grid cell; Let the horizontal weight gradient matrix P of the Earth fixed grid be: The horizontal weight of the grid cell at the j-th gradient for: ， The lower the weight, the greater the probability that the connection path between two adjacent grid cells will be selected as the shortest path jump; From the vertical weight gradient matrix The weight matrix of the Earth fixed grid is constructed using the horizontal weight gradient matrix P.

5. The autonomous on-board information path planning method for the Giants constellation according to claim 4, characterized in that, The grid path matrix for all passing grid cells is represented as G: The i-th grid cell in the shortest path is encoded as g. i : ， In the formula This represents the latitude of the center point of the i-th grid cell in the shortest path. This represents the longitude of the center point of the i-th grid cell in the shortest path; m is the total number of grid cells in the shortest path.

6. The autonomous on-board information path planning method for the Giants constellation according to claim 5, characterized in that, The constellation topology in the long-term visible topology resource set can communicate with the satellites in the current constellation topology; Assume all constellation topologies are star-shaped constellation topologies, and set the distance from the topological center star of the current constellation topology to 2. The star constellation topology containing all other topological central stars within the range constitutes a long-term visible set of topological resources. The long-term visible topological resource set is represented as V E : ， In the formula A star constellation topology within a long-term visible topological resource set. Central Star Located in the track In the position, For the current constellation topology The central star, current constellation topology Central Star Located at position y on orbit x, For the central star and the central star The angle between the line connecting to the Earth's center; The geocentric angle corresponding to the maximum visible distance between the two central stars is given. The topological central stars of all star-shaped constellations in the constellation Giants are evenly distributed on I orbits, with B topological central stars on each orbit. ， In the formula, H represents the thickness of the atmosphere.

7. The autonomous on-board information path planning method for the Giants constellation according to claim 6, characterized in that, The method for obtaining the set of intermittently visible topological resources is as follows: Construct a spherical triangle formed by the intersection of two orbits x1 and x2 with the equator from the I orbits. Let the center of the Earth be point O. Using the cosine theorem for spherical triangles, we can obtain the topology of constellations. The time when it intersects with the x2th orbit is t: ， ， ， ， In the formula The spherical angle corresponding to the equatorial arc. Let x1 and x2 be the inclination angles of the two tracks. Let x1 be the right ascension of the ascending node. Let x2 be the right ascension of the ascending node. constellation topology on orbit x1 When the central star intersects with orbit x2 orbital angle, For the central star The current true near point angle, For the central star The perigee argument, T is the central star. orbital period, For the central star The initial true anterior angle; Then the current constellation topology will be... The set of intermittently visible topological resources at time t is represented as V. IN : ， In the formula For the constellation topology in the intermittently visible topological resource set, constellation topology The central star is located at position b in orbit x2. Geocentric angle constraints corresponding to the allowable stable reverse communication distance: 。 8. The autonomous on-board information path planning method for the Giants constellation according to claim 7, characterized in that, If the grid cell corresponding to the satellite in the optimal window is on the shortest path from the mission initiation grid cell to the mission target grid cell, then in the grid path matrix... Remove the grid cell code g1 corresponding to the satellite in the best window to obtain the remaining grid path matrix. ; Otherwise, the optimal window satellite is determined based on the grid path matrix. In the corresponding neighborhood topology resource set, identify the neighboring satellite closest to the shortest path, and forward task information and grid path matrix to the grid cell corresponding to the neighboring satellite until the neighboring satellite is in the shortest path. Remove the grid cell code g1 corresponding to the satellite in the best window to obtain the remaining grid path matrix. .

9. The autonomous on-board information path planning method for the Giants constellation according to claim 8, characterized in that, During the process of sequentially determining intermediate transfer satellites from neighboring satellites, the same judgment process is performed on the neighboring satellites and intermediate transfer satellites as on the optimal window satellites and the neighboring satellites. The remaining grid path matrix is ​​obtained sequentially. In the formula, w represents the number of times the current grid cell code is deleted; After each intermediate transfer satellite is determined, if the current remaining grid path matrix satisfy Then continue to transmit satellite transmission mission information and the current remaining grid path matrix to the center. Until the task information reaches the target grid cell The corresponding optimal downlink intermediate satellite transmits the mission information to the mission target point, and the on-board decision-making and forwarding mission ends.

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