A satellite selection and switching method for Starlink satellite communication network based on scene conversion model

Abstract

The present invention belongs to the field of satellite communication technology, and specifically relates to a method for selecting and switching satellites in a Starlink satellite communication network based on a scene conversion model. Aiming at the selection of the Starlink low-orbit satellite communication system, a scene conversion star selection combination model is designed, so that the star selection process can be randomly combined according to the scene change, and at the same time, the most efficient star selection process is calculated through the scene conversion star selection combination model, thereby ensuring the timeliness and balance of the star selection; in addition, the present invention can achieve the most efficient multi-to-multi satellite ground station star selection in the Starlink satellite communication network, ensuring that the selected star link can stably complete the multi-to-multi satellite ground station star selection in various scenarios, greatly improving the multi-to-multi satellite selection efficiency of the Starlink satellite communication system satellite ground station.

Description

Technical Field

[0001] The present invention belongs to the technical field of satellite communications, and in particular relates to a satellite selection and switching method for a Starlink satellite communication network based on a scene conversion model. Background Art

[0002] With the modernization of the US GPS, the revival of the Russian GLONASS system, and the completion of the Chinese Beidou Satellite Navigation System (BDS) and the EU Galileo system, multi-system combined navigation and positioning has become a hot topic of research and application at home and abroad. Today, GPS and GLONASS are in normal operation with full constellations, and BDS and Galileo are in the construction stage. The number of visible satellites is generally lower than that of the first two systems. When the four systems are fully built, the total number of satellites in the sky will exceed 100, and the number of satellites that can be observed by the receiver at the same time will exceed 50. Compared with a single system, multi-system combined positioning has better reliability and stability. For example, in urban canyon areas, the combination of multiple systems can significantly increase the number of visible satellites.

[0003] However, when the number of satellites exceeds a certain number, the positioning performance will not continue to improve. On the contrary, too many satellites will lead to a significant increase in the amount of calculation, which will make the satellite ground station's satellite selection process time longer and less efficient, thus affecting the timeliness of positioning.

[0004] In view of this, in order to solve the above problems, the present invention designs a satellite selection and switching method for the Starlink satellite communication network based on a scene conversion model. Summary of the invention

[0005] Purpose of the invention: The purpose of the present invention is to address the deficiencies in the current technology and to provide a method for selecting and switching satellites in a Starlink satellite communication network based on a scene conversion model.

[0006] Technical solution: To achieve the above purpose, the present invention provides a method for selecting and switching satellites in a Starlink satellite communication network based on a scene conversion model, and the steps are as follows:

[0007] S1. Model the satellite ground station's star selection scenario and the switching between the various sub-satellite scenarios of Starlink;

[0008] S2. Analyze and model the relationship between multiple pairs of satellites on the ground stations;

[0009] S3. List the efficiency matrix of the Starlink communication system’s satellite selection in each scene change process, and abstract the scene change satellite selection combination model into a 0-1 integer programming problem;

[0010] S4. Solve the scene conversion star selection combination model and provide a solution algorithm to obtain the fastest feasible star selection process.

[0011] Furthermore, the modeling process in step S1 is as follows: the usage scenario of the satellite ground station is an organic whole based on the state, specific expression and conversion mode, which is recorded as Ω=<S, E, T>;

[0012] S represents the bandwidth margin state and power margin state in the usage scenario Ω, which is composed of all possible discrete states, denoted as S = (s1, s2, ..., s n ), any two states of S cannot exist at the same time;

[0013] E represents the impact of the S state in the usage scenario Ω, denoted as E = {E1, ..., E m}, and each impact is not a single state impact, but a collection of different states S and their corresponding probability of occurrence, so there is E m =(<s1,p1> ,<s2,p2> , …, n , p n >) m ,in And p i are different states i Probability of occurrence.

[0014] Furthermore, the state switching matrix T is recorded as:

[0015] in That is, p ij Indicates state s i Switch to state s j probability;

[0016] The relationship between status and impact is expressed as:

[0017] Among them, π i represents the probability distribution of future unknown states, λ i It represents the probability of state impact calculated based on historical data statistics or empirical knowledge, S t Indicates the current state, S t-1 represents the previous state, then the impact of the state change is expressed as:

[0018]

[0019] Then we have:

[0020]

[0021] Furthermore, the modeling process in step S2 is as follows: Assuming the selected star is x i The value is x i ∈{0,1} value, x​i =1 means the i-th star is selected by the star selection process, x i = 0 means that the i-th star is not selected by the star selection process. Define X as the star selection process, X = {x i |x i =1}; define the binary variable x at the same time (1,2) = 1 to describe the order relationship between the selected star x1 and the selected star x2. Similarly, the binary variable x (2,1) = 1 to describe the order relationship that the selected star x2 comes before the selected star x1; if x (1,2) =x (2,1) =1 means that the order of the two selected stars can be swapped at will.

[0022] Furthermore, in combination with the scene switching model in step S1 and the efficiency matrix in step S3, in the context of each star selection scene switching, the efficiency matrix of the T period can be expressed as the following matrix:

[0023]

[0024] v (i，j) t is the efficiency of the i-th selected star in the j-th state in the scene at time t, v x t is the total efficiency of the star selection process X at time t;

[0025] The average value of all scenes formed by the selected star in T time periods is expressed as Calculate using the following formula:

[0026]

[0027] Then, the overall efficiency of the entire star selection process X is v X The value of can be calculated using the following formula:

[0028]

[0029] Furthermore, in step S3, the maximum efficiency calculation formula of the star selection is as follows:

[0030]

[0031] Where AX≤B represents the time constraint of the star selection process and is set to an unquantified value. If the star selection process can achieve the maximum efficiency, the most feasible star selection scheme is obtained, which is recorded as X. F , and there is X F ={X|AX≤B}.

[0032] Furthermore, in said S4, the specific steps are as follows:

[0033] S11: Randomly generate star selection process X M , assuming X M The number of selected stars is M;

[0034] S12: Initialize the star selection process X M , ensure that the order of all star selections conforms to the order relationship of star selection;

[0035] S13: Calculation value;

[0036] S14: If there is a selected star Then x i Add to X M , then the star selection process becomes X M+1 ;

[0037] S15: If Then X M =X M+1 , otherwise X M remain unchanged;

[0038] S16: Traverse and select stars until the maximum maxv is obtained X (T);

[0039] S17: At this point, the fastest feasible star selection process X is obtained F =X M .

[0040] Beneficial effects: A scenario conversion star selection combination model is designed for the Starlink low-orbit satellite communication system, so that the star selection process can be randomly combined according to the scenario change. At the same time, the most efficient star selection process is calculated through the scenario conversion star selection combination model, thereby ensuring the timeliness and balance of star selection; in addition, the present invention can realize the most efficient multi-to-multi satellite ground station star selection in the Starlink satellite communication network, ensuring that the selected star link can stably complete the multi-to-multi satellite ground station star selection in various scenarios, greatly improving the many-to-many star selection efficiency of satellite ground stations in the Starlink satellite communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a flow chart of the present invention;

[0042] Figure 2 This is a transfer relationship diagram between different S, corresponding P and E of the present invention. DETAILED DESCRIPTION

[0043] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the accompanying drawings, and the words "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0044] Embodiment 1, according to Figure 1-Figure 2 Provide further explanation.

[0045] The present invention provides a method for selecting and switching satellites in a Starlink satellite communication network based on a scene conversion model, and the steps are as follows:

[0046] S1. Model the satellite ground station's star selection scenario and the switching between the various sub-satellite scenarios of Starlink;

[0047] The usage scenarios of the satellite ground station and the switching between the scenarios are modeled. The modeling process is as follows: the usage scenario of the satellite ground station is an organic whole based on the state, specific expression and conversion mode, which is recorded as Ω =<S,E,T> ;

[0048] S represents the bandwidth margin state and power margin state in the usage scenario Ω, which is composed of all possible discrete states, denoted as S = (s1, s2, ..., s n ), any two states of S cannot exist at the same time;

[0049] E represents the impact of the S state in the usage scenario Ω, denoted as E = {E1, ..., E m}, and each impact is not a single state impact, but a collection of different states S and their corresponding probability of occurrence, so there is E m =(<s1,p1> ,<s2,p2> , …, n , p n >) m ,in And p i are different states i Probability of occurrence.

[0050] According to the above-mentioned scene transition-based star selection combination model, the transition relationship between different states S, the corresponding occurrence probability P and its impact E is as follows: Figure 2 as stated;

[0051] according to Figure 2 , the state switching matrix T is recorded as:

[0052] in That is, p ij Indicates state s​i Switch to state s j probability;

[0053] The relationship between status and impact is expressed as: Among them, π i represents the probability distribution of future unknown states, λ i It represents the probability of state impact calculated based on historical data statistics or empirical knowledge, S t Indicates the current state, S t-1 represents the previous state, then the impact of the state change is expressed as:

[0054]

[0055] Then we have:

[0056]

[0057]

[0058] S2. Analyze and model the relationship between multiple pairs of satellites on the ground stations;

[0059] According to the scenario conversion-based star selection combination model, the relationship between the multi-to-multi star selection of the satellite ground station is analyzed and modeled. There is a dependency relationship between the star selection switching. For example, the multi-to-multi star selection must ensure that the bandwidth of the sub-star of the selected star chain is idle and the power of the sub-star of the selected star chain is not saturated. This is a dependency relationship; at the same time, different multi-to-multi star selection combinations also have an impact on the execution cost of the overall star selection process. For example, the disassembly of the multi-to-multi link must be placed at the end of the entire star selection process. If the order appears in the middle of the star selection process, it will affect the time cost of subsequent star selection. Therefore, for the star selection process of multiple star selection combinations, different combination orders have different effects on the time cost of star selection. The synergistic effect of multiple star selections is represented by discounting the sum of the cost impacts of all star selections, and the interaction between different star selections is described by modeling.

[0060] The modeling process in step S2 is: Assume that the selected star is x i The value is x i ∈{0,1} value, x i =1 means the i-th star is selected by the star selection process, x i = 0 means that the i-th star is not selected by the star selection process. Define X as the star selection process, X = {x i |x i =1}; define the binary variable x at the same time (1,2) = 1 to describe the order relationship between the selected star x1 and the selected star x2. Similarly, the binary variable x (2,1)= 1 to describe the order relationship that the selected star x2 comes before the selected star x1; if x (1,2) =x (2,1) =1 means that the order of the two selected stars can be swapped at will.

[0061] S3. List the efficiency matrix of the Starlink communication system’s satellite selection in each scene change process, and abstract the scene change satellite selection combination model into a 0-1 integer programming problem;

[0062] Combining the scene switching model in step S1 and the efficiency matrix in step S3, in the context of each star selection scene switching, the efficiency matrix of period T can be expressed as the following matrix:

[0063]

[0064] v (i，j) t is the efficiency of the i-th selected star in the j-th state in the scene at time t, v X t is the total efficiency of the star selection process X at time t;

[0065] In order to combine the actual usage of satellite ground stations, the average value of all scenes formed by the selected satellites in T time periods is expressed as Calculate using the following formula:

[0066]

[0067] Then, the overall efficiency of the entire star selection process X is v X The value of can be calculated using the following formula:

[0068]

[0069] The ultimate goal of the many-to-many satellite selection method for satellite ground stations is to maximize the efficiency of satellite selection under scene changes and fully reduce the time loss of the satellite selection process. This problem can be abstracted as a 0-1 integer programming problem to solve it. The formula is as follows:

[0070]

[0071] Where AX≤B represents the time constraint of the star selection process and is set to an unquantified value. If the star selection process can achieve the maximum efficiency, the most feasible star selection scheme can be obtained, which is recorded as X F , and there is X F ={X|AX≤B}.

[0072] S4. Solve the scene conversion star selection combination model and provide a solution algorithm to obtain the fastest feasible star selection process. The specific steps are as follows:

[0073] S11: Randomly generate star selection process X M , assuming X M The number of selected stars is M;

[0074] S12: Initialize the star selection process X M , ensure that the order of all star selections conforms to the order relationship of star selection;

[0075] S13: Calculation value;

[0076] S14: If there is a selected star Then x i Add to X M , then the star selection process becomes X M+1 ;

[0077] S15: If Then X M =X M+1 , otherwise X M remain unchanged;

[0078] S16: Traverse and select stars until the maximum max v is obtained X (T);

[0079] S17: At this point, the fastest feasible star selection process X is obtained F =X M .

[0080] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for selecting and switching satellites in a Starlink satellite communication network based on a scene conversion model, characterized in that: Here are the steps: S1. Model the satellite ground station's star selection scenario and the switching between the various sub-satellite scenarios of Starlink; S2. Analyze and model the relationship between multiple pairs of satellites on the ground stations; S3. List the efficiency matrix of the Starlink communication system’s satellite selection in each scene change process, and abstract the scene change satellite selection combination model into a 0-1 integer programming problem; S4. Solve the scene conversion star selection combination model and provide a solution algorithm to obtain the fastest feasible star selection process; The modeling process in step S1 is as follows: the usage scenario of the satellite ground station is an organic whole based on the state, specific expression and conversion mode, which is recorded as Ω=<S,E,T> ; S represents the bandwidth margin state and power margin state in the usage scenario Ω, which is composed of all possible discrete states, denoted as s = (s1, s2, ..., s n ), any two states of S cannot exist at the same time; E represents the impact of the S state in the usage scenario Ω, denoted as E = {E1, ..., E m }, and each impact is not a single state impact, but a collection of different states S and their corresponding probability of occurrence, so there is E m =(<s1,p1> ,<s2,p2> , …, n , p n >) m ,in And p i are different states i Probability of occurrence;​ The state switching matrix T is recorded as: in That is, p ij Indicates state s i Switch to state s j probability; The relationship between status and impact is expressed as: Among them, π i represents the probability distribution of future unknown states, λ i It represents the probability of state impact calculated based on historical data statistics or empirical knowledge, S t Indicates the current state, S t-1 represents the previous state, then the impact of the state change is expressed as: Then we have: The modeling process in step S2 is as follows: Assuming the selected star is x i The value is x i ∈{0,1} value, x i =1 means the i-th star is selected by the star selection process, x i = 0 means that the i-th star is not selected by the star selection process. Define X as the star selection process, X = {x i |x i =1}; define the binary variable x at the same time (1,2) = 1 to describe the order relationship between the selected star x1 and the selected star x2. Similarly, the binary variable x (2,1) = 1 to describe the order relationship that the selected star x2 comes before the selected star x1; if x (1,2) =x (2,1) =1 means the order of the two selected stars can be swapped at will; Combining the scene switching model in step S1 and the efficiency matrix in step S3, in the context of each star selection scene switching, the efficiency matrix of the T period can be expressed as the following matrix: v (i，j) t is the efficiency of the i-th selected star in the j-th state in the scene at time t, v X t is the total efficiency of the star selection process X at time t; The average value of all scenes formed by the selected star in T time periods is expressed as Calculate using the following formula: Then, the overall efficiency of the entire star selection process X is v X The value of can be calculated using the following formula: In step S3, the maximum efficiency calculation formula of the star selection is as follows: Where AX≤B represents the time constraint of the star selection process and is set to an unquantified value. If the star selection process can achieve the maximum efficiency, the most feasible star selection scheme is obtained, which is recorded as X. F , and there is X F ={X|AX≤B}; In said S4, the specific steps are as follows: S11: Randomly generate star selection process X M , assuming X M The number of selected stars is M; S12: Initialize the star selection process X M , ensure that the order of all star selections conforms to the order relationship of star selection; S13: Calculation value; S14: If there is a selected star Then x i Add to X M , then the star selection process becomes X M+1 ; S15: If Then X M =X M+1 , otherwise X M remain unchanged; S16: Traverse and select stars until the maximum maxv is obtained X (T); S17: At this point, the fastest feasible star selection process X is obtained F =X M .

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