Master-slave satellite cluster head pushing method based on multi-weight cost function

Abstract

The invention relates to a master-slave satellite cluster head pushing method based on a multi-weight cost function. The method comprises the following steps: establishing a communication model of a master-slave satellite cluster by adopting a graph theory method; determining a network state of the master-slave satellite cluster, wherein the network state is described by a transmission overhead matrix, a transmission distance matrix and a working state matrix in the satellite cluster; based on a communication model and a network state of a master-slave satellite cluster, introducing a composite weighting matrix, and constructing a multi-weight cost function of the satellite cluster; and calculating the priority of each node in the sub-satellite clusters according to the multi-weight cost function of the satellite cluster, and determining the node with the highest priority as the cluster head of the satellite cluster. According to the invention, the optimal networking communication quality and the highest communication efficiency of the whole network are realized, and the security and robustness of the network are enhanced at the same time.

Description

Technical Field

[0001] This invention belongs to the field of inter-satellite networking communication technology and relates to a master-slave satellite cluster leader election method based on a multi-weight cost function. Background Technology

[0002] With the rapid development of aerospace technology, satellites are undertaking increasingly complex missions, and satellite swarm collaboration is becoming an important technological development direction in the satellite field. Unlike large-scale low-Earth orbit internet constellations that use a unified satellite platform and payload architecture, satellite swarms are typically designed as a combination of a primary satellite and multiple secondary satellites to balance payload accuracy and mission flexibility. Satellites within a swarm need to exchange their orbital attitude, health status, and mission coordination information in real time; therefore, inter-satellite networks must be built through inter-satellite communication links to achieve communication link establishment, network management, routing scheduling, and data transmission.

[0003] To address the challenges of efficient transmission and information scheduling in master-slave satellite constellation inter-satellite networks, such as health management, task coordination and allocation, and task data collection from the master satellite to its satellites, a cluster head needs to be selected from within the satellite cluster. This cluster head acts as the satellite gateway, responsible for functions such as time synchronization and routing maintenance within the satellite network. An inappropriate cluster head selection can lead to low inter-satellite network transmission efficiency and high latency; a cluster head failure can even cause the master satellite to lose connection with the satellite cluster, resulting in mission failure. Therefore, a suitable method is needed for cluster head election in master-slave satellite constellations to achieve highly efficient and robust network communication. Summary of the Invention

[0004] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a master-slave satellite cluster head election method based on a multi-weight cost function, so as to achieve the optimal networking communication quality of the master-slave satellite cluster, improve transmission efficiency, and enhance network robustness.

[0005] The solution to the technical problem of this invention is: a master-slave satellite cluster head election method based on a multi-weight cost function, comprising the following steps:

[0006] A connectivity model for a master-slave satellite constellation is established using graph theory.

[0007] Determine the network state of the master-slave satellite cluster, which is described by the transmission overhead matrix, transmission distance matrix, and operational state matrix of the satellite cluster.

[0008] Based on the connectivity model and network status of the master-slave satellite cluster, a composite weighting matrix is ​​introduced to construct a multi-weight cost function for the satellite cluster.

[0009] The priority of each node in the sub-cluster is calculated based on the multi-weight cost function of the satellite cluster, and the node with the highest priority is determined as the cluster head of the satellite cluster.

[0010] Furthermore, the connectivity model of the master-slave satellite cluster is as follows:

[0011] A master-slave satellite constellation with node set V, link set E, and directed graph G = (V, E) is constructed using graph theory, where:

[0012] Node set V = {v1, v2, ..., v n} is defined as the set of all child nodes within a child cluster;

[0013] Link set E = {e1, e2, ..., e m} is defined as all reachable links between elements in a node set;

[0014] Based on the directed graph G of the sub-star cluster, define A = (a ij ) n×n Let G be the adjacency matrix of a directed graph, where:

[0015]

[0016] The reachability matrix P = (p ij ) m×n Calculated from adjacency matrix A:

[0017] Remember P0=A+A 2 +…+A n-1 The reachable matrix P is generated by changing all non-zero elements and all diagonal elements of matrix P0 to 1. The generated reachable matrix P is the connectivity model.

[0018] Furthermore, the transmission overhead matrix is ​​used to measure the information transmission overhead between nodes within the sub-cluster, and the matrix element is the channel quality factor c. ij Represents node ν i and ν j The signal-to-noise ratio factor between them was obtained by normalizing the channel signal-to-noise ratio after bidirectional acquisition by the inter-satellite communication unit in the early stage of network construction.

[0019]

[0020] Among them, SNR estimated Signal-to-noise ratio (SNR) of the channel after bidirectional acquisition by the inter-satellite communication unit. max This represents the maximum received signal-to-noise ratio of the communication device.

[0021] Furthermore, the transmission distance matrix is ​​used to represent the transmission distance of the link between nodes, and the matrix element d ij Represents node ν i With νj The distance factor between nodes ν i With ν j The actual transmission distance between them is normalized to obtain:

[0022]

[0023] Where, d max d represents the maximum communication distance between two nodes within a sub-cluster. estimated For node ν i With ν j The transmission distance between them is obtained by inter-satellite communication pseudocode ranging.

[0024] Furthermore, the operational status matrix is ​​used to measure the health status of each node. It is obtained by the satellite's onboard computer through a comprehensive evaluation and normalization of the satellite's battery power, individual machine self-test health status, and primary / backup machine redundancy.

[0025]

[0026] Furthermore, the multi-weighted cost function is Q = P[C,D,S]W T Where W = [η1, η2, η3] is the defined composite weighted matrix, and η i ,i=1,2,3 is a 1*n matrix, the weights are set by the ground allocation; C is the transmission overhead matrix, D is the transmission distance matrix, S is the working state matrix; Q is an n*1 matrix, each element in Q is the cost value of the sub-node, representing the priority of the sub-node.

[0027] Furthermore, after each node calculates its own priority, it broadcasts its own priority declaration within the cluster using a flooding method. After each node in the cluster receives the priority declarations from other nodes, the cluster head is determined based on the calculated value of the multi-weight cost function.

[0028] A computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of a master-slave satellite cluster head election method based on a multi-weighted cost function.

[0029] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of a master-slave satellite cluster head election method based on a multi-weight cost function.

[0030] A computer program product includes a computer program that, when executed by a processor, implements the steps of the master-slave satellite cluster head election method based on a multi-weight cost function.

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

[0032] This invention targets master-slave satellite cluster networks, constructing a multi-weighted cost function. By calculating the priority of each node, cluster head election is performed, allowing the cluster head to be dynamically adjusted based on factors such as the communication quality, communication distance, and working status of each node in the sub-cluster. This maximizes the timeliness of cluster head management in the sub-cluster, achieving optimal network communication quality and highest communication efficiency for the entire network, while also enhancing network security and robustness. Attached Figure Description

[0033] Figure 1 This is a flowchart of a master-slave satellite cluster head election method based on a multi-weight cost function according to the present invention; Figure 2 This is a directed graph within a sub-star cluster in an embodiment of the present invention; Figure 3 The figure shows the simulation results of the sub-star cluster head priority cost function in an embodiment of the present invention. Detailed Implementation

[0037] This invention proposes a cluster head election method based on a multi-weight cost function for master-slave satellite clusters. The master-slave satellite cluster includes a master satellite and multiple slave satellites, which form a slave satellite cluster. Each slave satellite is a node within the slave satellite cluster.

[0038] like Figure 1 As shown, the cluster head election method includes the following steps:

[0039] S1. Establish a connectivity model for a master-slave satellite cluster using graph theory methods;

[0040] S2. Determine the network state of the master-slave satellite cluster, which is described by the transmission overhead matrix, transmission distance matrix and working state matrix of the satellite cluster.

[0041] S3. Based on the connectivity model and network status of the master-slave satellite cluster, a composite weighting matrix is ​​introduced to construct a multi-weight cost function for the satellite cluster.

[0042] S4. Calculate the priority of each node in the sub-cluster based on the multi-weight cost function of the satellite cluster, and determine the node with the highest priority as the cluster head of the satellite cluster.

[0043] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0044] Example 1

[0045] like Figure 1 As shown, the cluster head election method in this embodiment includes the following steps:

[0046] S1. Establish a connectivity model for a master-slave satellite cluster using graph theory.

[0047] like Figure 2 As shown, a directed graph G = (V, E) is constructed using graph theory to establish the node set V, link set E, and master-slave satellite cluster, where:

[0048] Node set V = {v1, v2, ..., v n} is defined as the set of all child nodes within a child cluster;

[0049] Link set E = {e1, e2, ..., e m} is defined as all reachable links between elements in a node set;

[0050] Based on the directed graph G of the sub-star cluster, define A = (a ij ) n×n Let G be the adjacency matrix of a directed graph, where:

[0051]

[0052] The reachability matrix P = (p ij ) m×n It can be calculated from the adjacency matrix A:

[0053] Remember P0=A+A 2 +…+A n-1 The reachable matrix P is generated by changing all non-zero elements and all diagonal elements of matrix P0 to 1. The generated reachable matrix P is the connectivity model.

[0054] S2. Determine the network state of the master-slave satellite cluster, which is described by the transmission overhead matrix, transmission distance matrix and operating state matrix of the satellite cluster.

[0055] Transmission overhead matrix C: Used to measure the information transmission overhead between nodes within a sub-cluster; matrix element: channel quality factor c. ij Represents node ν i and ν j The signal-to-noise ratio factor between them was obtained by normalizing the channel signal-to-noise ratio after bidirectional acquisition by the inter-satellite communication unit in the early stage of network construction.

[0056]

[0057] Among them, SNR estimated Signal-to-noise ratio (SNR) of the channel after bidirectional acquisition by the inter-satellite communication unit. max This represents the maximum received signal-to-noise ratio of the communication device.

[0058] Transmission distance matrix D: used to represent the transmission distance of links between nodes, matrix element d ij Represents node ν i With ν j The distance factor between nodes ν i With ν j The actual transmission distance between them is normalized to obtain:

[0059]

[0060] Where, d max d represents the maximum communication distance between two nodes within a sub-cluster. estimated For node ν i With ν j The transmission distance between them can be obtained by inter-satellite communication pseudocode ranging.

[0061] The operational status matrix S is used to measure the health status of each node. It is obtained by the satellite's onboard computer through a comprehensive evaluation and normalization of factors such as the satellite's battery power, individual unit self-test health status, and redundancy of the primary and backup units.

[0062]

[0063] S3. Based on the connectivity model and network status of the master-slave satellite cluster, a composite weighted matrix is ​​introduced to construct a multi-weighted cost function for the satellite cluster.

[0064] The multi-weighted cost function is Q = P[C,D,S]W T Where W = [η1, η2, η3] is the defined composite weighted matrix, and η i i = 1, 2, 3 is a 1*n matrix with weights assigned by the ground; Q is an n*1 matrix where each element is the cost of a child node, representing the priority of the child node.

[0065] S4. Calculate the priority of each node in the sub-cluster based on the multi-weight cost function of the satellite cluster, and determine the node with the highest priority as the cluster head of the satellite cluster.

[0066] After each node calculates its priority, it broadcasts its own priority declaration within the cluster using a flooding method. Once each node in the cluster has received the priority declarations from other nodes, the cluster head can be determined based on the calculated value of the multi-weight cost function.

[0067] In this embodiment, a 7-satellite cluster system with 1 master satellite and 6 slave satellites is set up under a master-slave satellite cluster topology. The orbital parameters are shown in the table below:

[0068] Period Inclination Argument of Perigee RAAN True Anomaly Sat_Main 8h 42.48° 40.23° 0° 0° Sat1_Head 8h 42.6° 42.1° 0° 0° Sat2_Member 8h 42.0° 42.0° 0° 0° Sat3_Member 8h 42.25° 42.2° 0° 0° Sat4_Member 8h 42.5° 42.4° 0° 0° Sat5_Member 8h 42.75° 42.2° 0° 0° Sat6_Member 8h 43.0° 42.0° 0° 0°

[0069] Based on the above orbital parameters, a satellite cluster orbital model is established in the orbital simulation software. The distance between each sub-satellite changes dynamically between 18.9 km and 140.5 km as the constellation moves.

[0070] Simulation of the priority cost function of the sub-cluster head is as follows: Figure 3 As shown, due to differences in satellite orbital parameters, the relative distances and signal-to-noise ratios of nodes within the satellite cluster constantly change, resulting in a certain periodicity in the cluster head priority cost function. Establishing a subnet by arbitrarily selecting cluster heads may lead to significant communication overhead; however, using the priority cost function method can effectively select the sub-satellite with the lowest overall communication overhead as the cluster head of the subnet, and perform dynamic maintenance in each network maintenance cycle after network establishment, achieving optimal network communication quality and maximum communication efficiency for the entire network.

[0071] This application provides a computer-readable storage medium storing computer instructions that, when executed on a computer, cause the computer to perform... Figure 1 The method described.

[0072] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0073] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0074] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0075] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0076] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

[0077] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A master-slave satellite swarm leader election method based on a multi-weighted cost function, characterized in that, Includes the following steps: A connectivity model for a master-slave satellite constellation is established using graph theory. Determine the network state of the master-slave satellite cluster, which is described by the transmission overhead matrix, transmission distance matrix, and operational state matrix of the satellite cluster. Based on the connectivity model and network status of the master-slave satellite cluster, a composite weighting matrix is ​​introduced to construct a multi-weight cost function for the satellite cluster. The priority of each node in the sub-cluster is calculated based on the multi-weight cost function of the satellite cluster, and the node with the highest priority is determined as the cluster head of the satellite cluster.

2. The master-slave satellite cluster head election method based on a multi-weighted cost function according to claim 1, characterized in that, The connectivity model of the master-slave satellite cluster is as follows: A master-slave satellite constellation with node set V, link set E, and directed graph G = (V, E) is constructed using graph theory, where: Node set V = {v1, v2, ..., v n } is defined as the set of all child nodes within a child cluster; Link set E = {e1, e2, ..., e m } is defined as all reachable links between elements in a node set; Based on the directed graph G of the sub-star cluster, define A = (a ij ) n×n Let G be the adjacency matrix of a directed graph, where: The reachability matrix P = (p ij ) m×n Calculated from adjacency matrix A: Remember P0=A+A 2 +…+A n-1 The reachable matrix P is generated by changing all non-zero elements and all diagonal elements of matrix P0 to 1. The generated reachable matrix P is the connectivity model.

3. The master-slave satellite cluster head election method based on a multi-weighted cost function according to claim 1, characterized in that, The transmission overhead matrix is ​​used to measure the information transmission overhead between nodes within a sub-cluster, and the matrix element is the channel quality factor c. ij Represents node ν i and ν j The signal-to-noise ratio factor between them was obtained by normalizing the channel signal-to-noise ratio after bidirectional acquisition by the inter-satellite communication unit in the early stage of network construction. Among them, SNR estimated Signal-to-noise ratio (SNR) of the channel after bidirectional acquisition by the inter-satellite communication unit. max This represents the maximum received signal-to-noise ratio of the communication device.

4. The master-slave satellite cluster head election method based on a multi-weighted cost function according to claim 3, characterized in that, The transmission distance matrix is ​​used to represent the transmission distance of the link between nodes, and the matrix element d ij Represents node ν i With ν j The distance factor between nodes ν i With ν j The actual transmission distance between them is normalized to obtain: Where, d max d represents the maximum communication distance between two nodes within a sub-cluster. estimated For node ν i With ν j The transmission distance between them is obtained by inter-satellite communication pseudocode ranging.

5. The master-slave satellite cluster head election method based on a multi-weighted cost function according to claim 4, characterized in that, The operational status matrix is ​​used to measure the health status of each node. It is obtained by the satellite's onboard computer through a comprehensive evaluation and normalization of the satellite's battery power, individual unit self-test health status, and primary / backup unit redundancy.

6. The master-slave satellite cluster head election method based on a multi-weighted cost function according to claim 5, characterized in that, The multi-weighted cost function is Q = P[C,D,S]W T Where W = [η1, η2, η3] is the defined composite weighted matrix, and η i ,i=1,2,3 is a 1*n matrix, the weights are set by the ground allocation; C is the transmission overhead matrix, D is the transmission distance matrix, S is the working state matrix; Q is an n*1 matrix, each element in Q is the cost value of the sub-node, representing the priority of the sub-node.

7. The master-slave satellite cluster head election method based on a multi-weighted cost function according to claim 6, characterized in that, After each node calculates its own priority, it broadcasts its own priority declaration within the cluster using a flooding method. Once each node in the cluster has received the priority declarations from other nodes, the cluster head is determined based on the calculated value of the multi-weight cost function.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 7.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 7.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 7.

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