A ground station transit conflict resolution system and method

Abstract

This invention discloses a ground station transit conflict resolution system and method. It includes: a transit analysis module that establishes a simulation scenario of the satellite and ground station based on the satellite's orbital elements and the ground station's geographic information parameters, and calculates the time for the satellite's nadir trajectory to enter and exit the ground station; a conflict analysis module that generates a set of satellites with transit conflicts and a set of conflict time periods for each satellite, and truncates conflict time periods according to the time interval of adjacent receiving tasks of ground receiving resources and a satellite priority allocation strategy, generating a set of non-conflicting transit time periods for each satellite; and a scheme generation module that constructs a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculates the observation benefits of several feasible ground station transit time allocation schemes, and obtains the optimal planning scheme. This invention can improve the utilization rate of satellite-ground resources and the efficiency of satellite mission planning.

Description

Technical Field

[0001] This invention relates to the field of satellite planning and scheduling technology, and in particular to a ground station transit conflict resolution system and method. Background Technology

[0002] Currently, my country has over 20 civilian land observation satellites, including the Gaofen series satellites (GF-1, GF-1B / C / D, GF-2, GF-3, GF-4, GF-6, GF-7, etc.); the Ziyuan series satellites (ZY-3 01, ZY-3 02, ZY-3 03, ZY 02C, ZY 02D, etc.); the Environmental Disaster Reduction series satellites (HJ-2A / B); and the Electromagnetic series satellites (CSES). The data from these satellites are widely used in fields such as land resource surveys and monitoring, disaster prevention and mitigation, agriculture, forestry and water conservancy, ecological environment, urban planning and construction, and major national projects.

[0003] In recent years, my country's aerospace industry has developed rapidly, with the number of satellites in orbit constantly increasing. However, the construction cost of ground station receiving resources is relatively high, and their quantity and spatial distribution are constrained. As the number of satellites in orbit grows larger, the contradiction between this and the limitations of ground system receiving resources is becoming increasingly prominent. This is mainly manifested in the fact that for the same ground station receiving resource (the same receiving antenna), only downlink data from a single passing satellite can be received at any given time. Therefore, how to scientifically and rationally allocate ground station receiving resources to maximize satellite observation benefits, improve the utilization rate of the ground system, and fully utilize its receiving capabilities is an urgent problem to be solved. In addition, the inevitable conflicts between various observation needs increase the complexity of multi-satellite imaging mission planning and bring new challenges to the rational scheduling of the ground system.

[0004] For data transmission resource conflicts arising from multiple satellites passing overhead simultaneously, common solutions include: ① "first-come, first-served" downloading, meaning fully receiving the data resources of the satellite that arrives first; ② prioritizing satellite data by priority; ③ prioritizing data from satellites with higher priority based on the importance of the demand; and ④ constructing a mutual exclusion model based on a mutual exclusion matrix to obtain the optimal solution that yields the highest observational benefit. Among these methods, methods ① and ② waste data transmission resources and do not maximize observational benefit; method ③, while guaranteeing the highest observational benefit, also wastes data transmission resources; and method ④ involves a complex model solution, which is not conducive to routine operational use. Furthermore, manually judging ground station receiving resource conflicts is time-consuming, labor-intensive, and prone to errors, making it unsuitable for practical application in satellite mission planning. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a ground station transit conflict resolution system and method.

[0006] The technical solution of this invention is:

[0007] In a first aspect, embodiments of the present invention provide a ground station transit conflict resolution system, the system comprising: a transit analysis module, a conflict analysis module, and a solution generation module, wherein...

[0008] The transit analysis module is configured to establish a simulation scenario of the satellite and ground station in the STK software based on the satellite's orbital elements and the geographic information parameters of the ground station, calculate the time for the satellite's nadir point trajectory to enter and exit the ground station, and display it in the user interface.

[0009] The conflict analysis module is configured to generate a set of satellites that have transit conflicts with each satellite and a set of conflict time periods for each satellite. Based on the time interval of adjacent reception tasks of ground reception resources, the conflict time periods are truncated according to the satellite priority allocation strategy. A set of non-conflicting transit times is generated for each satellite and displayed in the user interface.

[0010] The scheme generation module is configured to construct a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculate the observation benefits of several feasible ground station transit time allocation schemes, and obtain the optimal planning scheme.

[0011] Optionally, the transit analysis module is also configured to interconnect Matlab software and STK software to establish a simulation scenario of the satellite and ground station in the STK software based on the satellite's orbital elements and the geographic information parameters of the ground station.

[0012] Optionally, the conflict analysis module is further configured to determine the satellites whose transit times overlap based on the arc segments of each satellite passing over the ground station, and generate a set of satellites that have transit conflicts with each satellite and a set of conflict time periods for each satellite.

[0013] Secondly, embodiments of the present invention provide a ground station transit conflict resolution method, applied to any of the systems described above, the method comprising:

[0014] Based on the satellite's orbital elements and the ground station's geographic information parameters, a simulation scenario of the satellite and ground station is established in the STK software. The time for the satellite's nadir point trajectory to enter and exit the ground station is calculated and displayed in the user interface.

[0015] For each satellite, a set of satellites that have transit conflicts with it and a set of conflict time periods are generated. Based on the time interval of adjacent reception tasks of ground reception resources, the conflict time periods are truncated according to the satellite priority allocation strategy. For each satellite, a set of non-conflicting transit times is generated and displayed in the user operation interface.

[0016] Based on satellite priority, a non-mutually exclusive chain is constructed for the satellite transit time set. The observation benefits of the obtained several feasible ground station transit time allocation schemes are calculated to obtain the optimal planning scheme.

[0017] Optionally, the step of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes, and obtaining the optimal planning scheme includes:

[0018] When the priority of the first satellite is higher than that of the second satellite, the first satellite is controlled to receive data transmission resources for the entire transit arc.

[0019] Determine whether the time interval between the overpass start time of the first satellite and the overpass start time of the second satellite is greater than a first interval threshold.

[0020] If so, the receiving task of the second satellite is completed within the time period from the start time of the second satellite's transit to the time difference between the start time of the first satellite's transit and the first interval threshold; otherwise, the data transmission task of the second satellite is discarded.

[0021] When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the entire transit arc.

[0022] Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than the first interval threshold.

[0023] If so, the data transmission task of the first satellite is received from the sum of the transit end time of the second satellite and the first interval threshold, starting from the transit end time of the first satellite; otherwise, the data transmission task of the first satellite is discarded.

[0024] Optionally, the step of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes, and obtaining the optimal planning scheme includes:

[0025] When the priority of the first satellite is higher than that of the second satellite, control the first satellite to receive data transmission resources for the entire transit arc.

[0026] Determine whether the time interval between the transit start time of the first satellite and the transit start time of the second satellite is greater than a second interval threshold.

[0027] If so, the receiving task of the second satellite is completed from the start time of the second satellite's transit to the start time of the first satellite's transit minus the second interval threshold.

[0028] If not, then the data transmission task of the second satellite will be abandoned;

[0029] Again, determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than the second interval threshold.

[0030] If so, then the data transmission task of the second satellite will be received starting from the end time of the first satellite's transit plus the second interval threshold, until the end time of the second satellite's transit.

[0031] If not, then the second satellite's subsequent data transmission task will be abandoned.

[0032] Optionally, the step of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes, and obtaining the optimal planning scheme includes:

[0033] When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the entire transit arc.

[0034] Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than a second interval threshold.

[0035] If so, the data transmission task of the first satellite is received starting from the sum of the transit end time of the second satellite and the second interval threshold, until the transit end time of the first satellite is reached.

[0036] If not, then the data transmission task of the first satellite will be abandoned.

[0037] Optionally, the step of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes, and obtaining the optimal planning scheme includes:

[0038] When the priority of the first satellite is higher than that of the second satellite, control the first satellite to receive data transmission resources for the entire transit arc.

[0039] Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than a third interval threshold.

[0040] If so, the data from the second satellite is received starting from the sum of the transit end time of the first satellite and the third interval threshold, until the transit end time of the second satellite is reached.

[0041] If not, discard the data transmission task of the second satellite.

[0042] Optionally, the step of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes, and obtaining the optimal planning scheme includes:

[0043] When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the entire transit arc.

[0044] Starting from the transit start time of the first satellite, the data transmission task of the first satellite is received until the end time is reached, which is the difference between the transit start time of the second satellite and the third interval threshold.

[0045] The advantages of this invention compared to existing technologies are as follows: This invention proposes a conflict resolution method based on satellite priority and non-mutually exclusive chains to address ground station conflicts during the downlink process of multi-satellite imaging missions. By predicting the accurate time of each satellite passing over ground stations and determining the conflict situation, a priority strategy is used to extract conflict periods, resulting in a set of ground station passing times that do not conflict and maximize satellite observation benefits, thereby improving the utilization rate of satellite and ground resources and the efficiency of satellite mission planning. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of a ground station transit conflict resolution system provided in an embodiment of the present invention;

[0047] Figure 2 A schematic diagram of the interface of a ground station transit conflict resolution system based on satellite priority and non-mutually exclusive chains, provided for an embodiment of the present invention;

[0048] Figure 3 A schematic diagram illustrating the calculation results of a transit analysis model provided in an embodiment of the present invention;

[0049] Figure 4 A schematic diagram of the conflict analysis module interface of a ground station transit conflict resolution system based on satellite priority and non-mutually exclusive chains, provided for an embodiment of the present invention;

[0050] Figure 5 A schematic diagram illustrating the calculation results of a conflict analysis module provided in an embodiment of the present invention;

[0051] Figure 6 A schematic diagram of the interface of a scheme generation module for a ground station transit conflict resolution system based on satellite priority and non-mutually exclusive chains provided in an embodiment of the present invention;

[0052] Figure 7 A schematic diagram illustrating the calculation results of a scheme generation module provided in an embodiment of the present invention;

[0053] Figure 8 A schematic diagram of a simulation process provided for an embodiment of the present invention;

[0054] Figure 9 A schematic diagram illustrating a satellite transit conflict scenario provided in an embodiment of the present invention;

[0055] Figure 10 This is a flowchart illustrating the steps of a ground station transit conflict resolution method provided in an embodiment of the present invention. Detailed Implementation

[0056] To address the issue of conflicting ground station resource usage periods during the planning of several satellite missions, including the Resource, High-Resolution, and Civil Space-based series satellites, and to reduce resource waste caused by these conflicts and inconveniences arising from the inability to coordinate ground station usage during satellite mission planning, it is crucial to comprehensively coordinate and resolve conflicts related to ground station resource usage to achieve rational allocation of resources for each satellite. Ground station usage coordination software can pre-allocate ground station resources for satellites, comprehensively analyze ground station usage during satellite mission planning, and provide conflict warnings. This helps resolve conflicts in ground station selection periods during the planning of the Resource, High-Resolution, and Civil Space-based systems, ultimately achieving rational allocation and use of ground station resources.

[0057] This invention addresses ground station conflicts during the downlink process of multi-satellite imaging missions by proposing a conflict resolution method based on satellite priority and non-mutually exclusive chains. By predicting the accurate time of each satellite's transit over ground stations and determining the conflict situation, a priority strategy is used to extract conflict periods, resulting in a set of transit ground station times that are mutually non-conflicting and maximize satellite observation benefits. This improves the utilization rate of satellite and ground resources and the efficiency of satellite mission planning.

[0058] The technical solutions of the embodiments of the present invention will be described in detail below with reference to specific examples.

[0059] Example 1

[0060] Reference Figure 1 The diagram shows a schematic representation of a ground station transit conflict resolution system provided in an embodiment of the present invention. Figure 1 As shown, the ground station transit conflict resolution system 100 may include: a transit analysis module 110, a conflict analysis module 120, and a solution generation module 130, wherein,

[0061] The transit analysis module is configured to establish a simulation scenario of the satellite and ground station in the STK software based on the satellite's orbital elements and the geographic information parameters of the ground station, calculate the time for the satellite's nadir point trajectory to enter and exit the ground station, and display it in the user interface.

[0062] In this embodiment, one of the key technologies for resolving ground station transit conflicts is to accurately predict the time window for satellite transit over ground stations. Commonly used methods for calculating satellite transit time windows include: orbit prediction transit calculation based on the SGP4 (Simplified General Perturbations) model, orbit prediction transit calculation based on the HPOP (High Precision Orbit Propagator) model, and satellite transit calculation based on STK simulation. The SGP4 model takes into account the effects of perturbations such as Earth's non-spherical gravity, lunar and solar gravity, solar radiation pressure, and atmospheric drag, and is applied to near-Earth objects with orbital periods of less than 225 minutes. The HPOP model first constructs a suitable perturbation model based on the orbital type, then establishes the orbital differential equation, i.e., the differential relationship between the satellite's instantaneous acceleration and position-velocity. Finally, it uses numerical methods to integrate the orbital differential equation to obtain the predicted position and velocity results. STK software, a leading system analysis and simulation software in the aerospace field, includes two forms of orbit prediction algorithms (analytical and numerical algorithms) and multiple orbit prediction models (including the SGP4 and HPOP models), which can conveniently and accurately calculate the satellite's visibility window to the target. This invention uses a simulation method based on STK to calculate satellite transit. The STK software's built-in modules have functions such as generating instantaneous spacecraft position and attitude data, visibility analysis, and coverage analysis. The visibility analysis module is used to calculate the satellite's ground station transit window. This module can calculate the access time between any objects and display it in an animation in a two-dimensional map window. The calculation results can also be presented as charts or text reports. In addition, the STK's built-in module also supports adding geometric constraints between objects, such as the sensor's field of view, the minimum elevation angle, azimuth angle, and field of view distance of ground-based or space-based systems.

[0063] Calculating ground station transit windows for multiple satellites using STK involves iterative calculations, complex nested iterations, and intricate convergence criteria. However, STK itself cannot be programmed to perform simulation analysis of certain space missions. Therefore, this invention utilizes STK's connection module and its built-in interface to interconnect with a third-party application (Matlab), facilitating the implementation of complex logic. STK includes hundreds of pre-packaged interface functions for interconnecting with Matlab, providing bidirectional communication between the two software programs, as shown in Appendix Table 1.

[0064] Table 1

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071] There are two main ways to interconnect STK and Matlab: one is the "connect interface," and the other is the "com interface." The second method is relatively simpler. This invention adopts the "com interface" approach: ① First, the "actxserver()" interface function is used to establish a connection between the STK and Matlab software; ② Then, the "root.NewScenario()" interface function is used to create a simulation scene and initialize and set preferences for the scene; ③ The "sc.Children.New()" interface function is used to create satellite and ground station objects respectively. The satellite objects are created in batches by reading the latest two rows of root data from multiple satellites; the ground station objects are configured with parameters such as geographical location, antenna type, and receiving elevation angle based on their actual information; ④ Finally, the "GetAccessToObject()" and "ComputeAccess()" interface functions are used to calculate the number of visible points and visible arcs between the satellite and the ground station, and the transit window is displayed in the Matlab software interface (see appendix). Figure 2 and attached Figure 3 The simulation process is attached. Figure 8 .

[0072] The conflict analysis module is configured to generate a set of satellites that have transit conflicts with each satellite and a set of conflict time periods for each satellite. Based on the time interval of adjacent reception tasks of ground reception resources, the conflict time periods are truncated according to the satellite priority allocation strategy. A set of non-conflicting transit times is generated for each satellite and displayed in the user interface.

[0073] In this embodiment, due to limitations in the quantity and spatial distribution of ground receiving resources, when multiple satellites simultaneously enter the receiving range of a ground station, a single antenna can only receive downlink data from one satellite during the overlapping period. During non-overlapping periods, after completing the data transmission task of one satellite, the ground system will perform a 270-second preparation period for the next receiving task. This means that the start time of the second satellite's data transmission and the end time of the first satellite's data transmission must be at least 270 seconds apart to ensure no collisions occur. This invention transforms the collisions of multiple satellites within the same ground station's receiving range at the same time into a collision problem between each pair of satellites. When two satellites simultaneously enter the receiving range of a ground station, there is a possibility of collisions between them. Figure 9 The diagram shows six conflict scenarios, where [a1, a2] represent the transit time of satellite A, and [b1, b2] represent the transit time of satellite B. Conflict resolution is based on satellite priority and the importance of the requirement.

[0074] For scenario ①, when satellite A has a higher priority than satellite B, satellite A will receive data transmission resources for the entire transit arc. Then, it will determine if the time interval between a1 and b1 satisfies 270 seconds. If it does, it will begin receiving data from satellite B from time b1 until (a1-270 seconds), completing part of the reception task. If not, it will discard the data transmission task for satellite B at that station. When satellite A has a lower priority than satellite B, satellite B will receive data transmission resources for the entire transit arc. Then, it will determine if the time interval between a2 and b2 satisfies 270 seconds. If it does, it will begin receiving data from satellite A from (b2+270 seconds) until time a2, stopping the reception. If not, it will discard the data transmission task for satellite A at that station.

[0075] For scenario ②, when satellite A has a higher priority than satellite B, satellite A will receive the data transmission resources for the entire transit arc. Then, it checks if the time interval between a2 and b2 satisfies 270 seconds. If it does, it starts receiving satellite B's resources from (a2+270 seconds) and stops at time b2. If it doesn't, it discards satellite B's data transmission task. When satellite A has a lower priority than satellite B, after fully receiving satellite B's resources, it checks if the time interval between a1 and b1 satisfies 270 seconds. If it does, it starts receiving satellite A's data from time a1 and stops at (b1-270 seconds). If it doesn't, it discards satellite A's data transmission task.

[0076] Cases ③ and ④ are essentially the same. In case ③, when satellite A has a higher priority than satellite B, satellite A will also receive the data transmission resources for the complete transit arc. Then, it checks if the time interval between a1 and b1 satisfies 270 seconds. If it does, it starts receiving satellite B's resources from time b1 and stops receiving at (a1-270 seconds). If it doesn't, it will no longer receive satellite B's resources during that period. Next, it checks if the time interval between a2 and b2 satisfies 270 seconds. If it does, it can continue receiving the latter half of satellite B's data transmission tasks; if not, it will no longer receive satellite B's resources for that segment. When satellite A has a lower priority than satellite B, satellite B will receive the resources for the complete transit arc, discarding all data transmission tasks from satellite A at that station. Case ④ is similar to case ③; its transit period is calculated as the reverse of case ③.

[0077] Similarly, scenarios ⑤ and ⑥ involve two similar processes. In scenario ⑤, when satellite A has a higher priority than satellite B, satellite A will receive the complete data transmission resources; then it is determined whether the time interval between a2 and b2 satisfies 270. s If satisfied, then from ( a 2+270 s Data transmission from satellite A begins at time a1 and ends at time b2; if the conditions are not met, the data transmission task for satellite B is discarded. When satellite A has a lower priority than satellite B, satellite B will receive the complete data transmission resources; satellite A begins receiving data at time a1 and ends at (b1-270s). Case ⑥ is similar.

[0078] After constructing a non-mutually exclusive chain based on satellite priorities, several feasible ground station transit time allocation schemes are obtained within the planned time period. Then, among these schemes, the optimal planning scheme is selected based on the satellite resource duration and the importance of the demand. Based on this idea, by reading the transit window file generated by Module 1, satellites and transit windows that conflict with each satellite's transit can be sequentially filtered out. Conflicts between each satellite can be resolved according to a priority strategy. Finally, the results are displayed in the UI interface using the interconnection function between STK and Matlab. (See appendix.) Figure 4 and attached Figure 5 This provides a basis for decision-making in planning the optimal solution later.

[0079] The scheme generation module is configured to construct a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculate the observation benefits of several feasible ground station transit time allocation schemes, and obtain the optimal planning scheme.

[0080] Based on the conflict analysis results, several feasible ground station transit time allocation schemes will be obtained within the planned time period. Subsequently, the optimal planning scheme needs to be selected from these schemes based on the satellite resource duration and the importance of the demand. Different weights are assigned to the total reception duration of the receiving scheme, the reception duration of several high-priority satellites, and the benefit of the demand, resulting in a comprehensive score, which serves as the basis for selecting the optimal scheme. In the set of all non-conflicting satellite resource downlinks, the benefits of the above three factors are defined as follows:

[0081] Total time earnings:

[0082] Where benefit_time(i) represents the total reception time benefit of a certain plan; plan_time(i) represents the total reception time of a certain plan; and n is the number of mutually non-conflicting plans. This paper considers GFDM, GF2, and GF7 as high-priority satellites, defines "high-priority satellite benefit" based on the reception time of these satellite resources, and assigns different weights to different satellites:

[0083] Benefits of higher priority satellites:

[0084] Where benefit_sat(i) represents the benefit of higher priority satellites; GFDM_time(i), GF2_time(i), and GF7_time(i) represent the reception duration of these satellites in scheme i, respectively; a, b, and c represent different weights, which can be obtained from experience and adjusted according to the actual situation of daily planning; n represents the number of non-conflicting schemes. Finally, based on the quantity and importance of demand undertaken in each scheme, the "demand benefit" is defined as follows:

[0085] Demand benefit: benefit_need(i)=m*count(i)+n*imp(i) (3)

[0086] Where benefit_need(i) represents the benefit of solution i; count(i) represents the number of demands undertaken by solution i; imp(i) represents the importance of demands in solution i; m and n represent the weights of the number and importance of demands, respectively, and are assigned empirical values ​​based on the actual task situation. Based on the above three benefits, the comprehensive score of a solution is defined as:

[0087] score(i)=α*benefit_time(i)+β*benefit_sat(i)+γ*benefit_need(i) (4)

[0088] Where score(i) is the final score of scheme i, and the optimal planning scheme is selected based on the value; α, β, and γ are the weights of the three benefits, and the weights are assigned according to the actual planning situation. For example, setting α to 0.3, β to 0.3, and γ to 0.4 based on prior knowledge can yield a more ideal planning result.

[0089] The conflict-passing algorithm based on satellite priority and non-mutually exclusive chains prioritizes satellites during implementation, ensuring complete reception of data transmission resources from higher-priority satellites while shortening the transit times of conflicting lower-priority satellites. For critical or emergency tasks, complete downlink transmission is guaranteed, reflecting the "satellite priority" principle. In a downlink link generated by this method, the time interval between satellites transiting at the same time will be greater than 270 seconds, eliminating conflicts—a "non-mutually exclusive chain." However, in actual satellite imaging mission planning, satellite priorities are not static, and daily transit times vary slightly depending on the satellite imaging strategy. Therefore, the output results need to be verified or fine-tuned based on the specific needs of the day to maximize the utilization of satellite and ground resources. The daily plans are sorted in descending order of benefit score, and the plan with the highest benefit score is displayed in the UI, as shown in the attached image. Figure 6 and attached Figure 7 This serves as the basis for users to select stations when planning their tasks.

[0090] Example 2

[0091] Reference Figure 10 This diagram illustrates a flowchart of a ground station transit conflict resolution method provided by an embodiment of the present invention. This ground station transit conflict resolution method can be applied to the ground station transit conflict resolution system described in the above embodiment, such as... Figure 10 As shown, the method may include the following steps:

[0092] Step 1001: Based on the satellite's orbital elements and the ground station's geographic information parameters, establish a simulation scenario of the satellite and ground station in the STK software, calculate the time for the satellite's nadir point trajectory to enter and exit the ground station, and display it in the user interface.

[0093] In this embodiment, one of the key technologies for resolving ground station transit conflicts is to accurately predict the time window for satellite transit over ground stations. Commonly used methods for calculating satellite transit time windows include: orbit prediction transit calculation based on the SGP4 (Simplified General Perturbations) model, orbit prediction transit calculation based on the HPOP (High Precision Orbit Propagator) model, and satellite transit calculation based on STK simulation. The SGP4 model takes into account the effects of perturbations such as Earth's non-spherical gravity, lunar and solar gravity, solar radiation pressure, and atmospheric drag, and is applied to near-Earth objects with orbital periods of less than 225 minutes. The HPOP model first constructs a suitable perturbation model based on the orbital type, then establishes the orbital differential equation, i.e., the differential relationship between the satellite's instantaneous acceleration and position-velocity. Finally, it uses numerical methods to integrate the orbital differential equation to obtain the predicted position and velocity results. STK software, a leading system analysis and simulation software in the aerospace field, includes two forms of orbit prediction algorithms (analytical and numerical algorithms) and multiple orbit prediction models (including the SGP4 and HPOP models), which can conveniently and accurately calculate the satellite's visibility window to the target. This invention uses a simulation method based on STK to calculate satellite transit. The STK software's built-in modules have functions such as generating instantaneous spacecraft position and attitude data, visibility analysis, and coverage analysis. The visibility analysis module is used to calculate the satellite's ground station transit window. This module can calculate the access time between any objects and display it in an animation in a two-dimensional map window. The calculation results can also be presented as charts or text reports. In addition, the STK's built-in module also supports adding geometric constraints between objects, such as the sensor's field of view, the minimum elevation angle, azimuth angle, and field of view distance of ground-based or space-based systems.

[0094] Calculating ground station transit windows for multiple satellites using STK involves iterative calculations, complex nested iterations, and intricate convergence criteria. However, STK itself cannot be programmed to perform simulation analysis of certain space missions. Therefore, this invention utilizes STK's connection module and its built-in interface to interconnect with a third-party application (Matlab), facilitating the implementation of complex logic. STK includes hundreds of pre-packaged interface functions for interconnecting with Matlab, providing bidirectional communication between the two software programs, as shown in Appendix 1 above. There are two main ways to interconnect STK and Matlab: one is the "connect interface," and the other is the "com interface." The second method is relatively simpler. This invention adopts the "com interface" approach: ① First, the "actxserver()" interface function is used to establish a connection between the STK and Matlab software; ② Then, the "root.NewScenario()" interface function is used to create a simulation scene and initialize and set preferences for the scene; ③ The "sc.Children.New()" interface function is used to create satellite and ground station objects respectively. The satellite objects are created in batches by reading the latest two rows of root data from multiple satellites; the ground station objects are configured with parameters such as geographical location, antenna type, and receiving elevation angle based on their actual information; ④ Finally, the "GetAccessToObject()" and "ComputeAccess()" interface functions are used to calculate the number of visible points and visible arcs between the satellite and the ground station, and the transit window is displayed in the Matlab software interface.

[0095] Step 1002: For each satellite, generate a set of satellites that have transit conflicts with it and a set of conflict time periods. Based on the time interval of adjacent reception tasks of ground reception resources, truncate the conflict time periods according to the satellite priority allocation strategy, generate a set of non-conflicting transit times for each satellite, and display them in the user interface.

[0096] In this embodiment, a set of satellites that have transit conflicts with each satellite and a set of conflict time periods can be generated for each satellite. Based on the time interval of adjacent reception tasks of ground reception resources, the conflict time periods are truncated according to the satellite priority allocation strategy. A set of non-conflicting transit times is generated for each satellite and displayed in the user interface.

[0097] Due to limitations in the quantity and spatial distribution of ground receiving resources, when multiple satellites simultaneously enter the receiving range of a ground station, a single antenna can only receive downlink data from one satellite during the overlapping period. During non-overlapping periods, after completing the data transmission task of one satellite, the ground system will perform a 270-second preparation period for the next receiving task. This means that the start time of the second satellite's data transmission must be at least 270 seconds apart from the end time of the first satellite's data transmission to ensure no collisions occur. This invention transforms the collisions of multiple satellites within the same ground station's receiving range during the same time period into a collision problem between each pair of satellites. When two satellites simultaneously enter the receiving range of a ground station, there is a possibility of collisions between them. Figure 8 The diagram shows six conflict scenarios, where [a1, a2] represent the transit time of satellite A, and [b1, b2] represent the transit time of satellite B. Conflict resolution is based on satellite priority and the importance of the requirement.

[0098] Step 1003: Based on satellite priority, construct a non-mutually exclusive chain of satellite transit time sets, calculate the observation benefits of several feasible ground station transit time allocation schemes, and obtain the optimal planning scheme.

[0099] Based on the conflict analysis results, several feasible ground station transit time allocation schemes will be obtained within the planned time period. Subsequently, the optimal planning scheme needs to be selected from these schemes based on the satellite resource duration and the importance of the demand. Different weights are assigned to the total reception duration of the receiving scheme, the reception duration of several high-priority satellites, and the benefit of the demand, resulting in a comprehensive score, which serves as the basis for selecting the optimal scheme.

[0100] The implementation process can be described in detail below with reference to the specific implementation methods.

[0101] In one specific implementation of the present invention, step 103 may include:

[0102] Sub-step A1: When the priority of the first satellite is higher than that of the second satellite, control the first satellite to receive data transmission resources for the entire transit arc.

[0103] Sub-step A2: Determine whether the time interval between the start time of the first satellite's transit and the start and end time of the second satellite's transit is greater than the first interval threshold.

[0104] Sub-step A3: If yes, then the receiving task of the second satellite is completed within the time period from the start time of the second satellite's transit to the time difference between the start time of the first satellite's transit and the first interval threshold; otherwise, the data transmission task of the second satellite is discarded.

[0105] Sub-step A4: When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the entire transit arc;

[0106] Sub-step A5: Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than the first interval threshold;

[0107] Sub-step A6: If yes, then start receiving the data transmission task of the first satellite from the sum of the transit end time of the second satellite and the first interval threshold, until the transit end time of the first satellite; otherwise, discard the data transmission task of the first satellite.

[0108] In this embodiment, when satellite A has a higher priority than satellite B, satellite A will receive data transmission resources for the entire transit arc. Then, it will determine whether the time interval between a1 and b1 satisfies 270s. If it does, it will complete part of satellite B's reception task from time b1 to (a1-270s). If not, the data transmission task for satellite B at this station will be discarded. When satellite A has a lower priority than satellite B, satellite B will receive data transmission resources for the entire transit arc. Then, it will determine whether the time interval between a2 and b2 satisfies 270s. If it does, it will start receiving satellite A's data transmission task from (b2+270s) to time a2. If not, the data transmission task for satellite A at this station will be discarded.

[0109] In another specific implementation of the present invention, step 103 may include:

[0110] Sub-step B1: When the priority of the first satellite is higher than that of the second satellite, control the first satellite to receive data transmission resources for the entire transit arc.

[0111] Sub-step B2: Determine whether the time interval between the transit start time of the first satellite and the transit start time of the second satellite is greater than the second interval threshold;

[0112] Sub-step B3: If so, then starting from the transit start time of the second satellite, the transit start time of the first satellite minus the second interval threshold is used to complete the receiving task of the second satellite;

[0113] Sub-step B4: If not, discard the data transmission task of the second satellite;

[0114] Sub-step B5: Determine again whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than the second interval threshold;

[0115] Sub-step B6: If so, start receiving data transmission tasks from the second satellite from the end time of the first satellite's transit plus the second interval threshold until the end time of the second satellite's transit.

[0116] Sub-step B7: If not, discard the second satellite's back-end data transmission task.

[0117] In another specific implementation of the present invention, step 103 may further include:

[0118] Sub-step C1: When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the complete transit arc;

[0119] Sub-step C2: Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than the second interval threshold;

[0120] Sub-step C3: If so, then take the sum of the transit end time of the second satellite and the second interval threshold as the starting time, and receive the data transmission task of the first satellite until the transit end time of the first satellite is reached.

[0121] Sub-step C4: If not, discard the data transmission task of the first satellite.

[0122] In this embodiment of the invention, when satellite A has a higher priority than satellite B, satellite A will receive the data transmission resources for the complete transit arc. Then, it is determined whether the time interval between a1 and b1 meets the requirement of 270s. If it does, satellite A will start receiving satellite B resources from time b1 and stop receiving at (a1-270s). If it does not meet the requirement, satellite B resources will no longer be received during this period. Next, it is determined whether the time interval between a2 and b2 meets the requirement of 270s. If it does, satellite A can continue to receive the data transmission task for the second half of satellite B. If it does not meet the requirement, satellite B resources for this segment will no longer be received.

[0123] When satellite A has a lower priority than satellite B, satellite B will receive the resources of the complete transit arc and discard all data transmission tasks of satellite A at that station. Determine if the time interval between a2 and b2 meets the requirement of 270s. If it does, begin receiving data transmission tasks from satellite A at (b2+270s) and stop receiving at time a2; otherwise, discard data transmission tasks from satellite A at that station.

[0124] In another specific implementation of the present invention, step 103 may further include:

[0125] Sub-step D1: When the priority of the first satellite is higher than that of the second satellite, control the first satellite to receive data transmission resources for the entire transit arc.

[0126] Sub-step D2: Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than the third interval threshold;

[0127] Sub-step D3: If so, then start receiving data from the second satellite with the sum of the transit end time of the first satellite and the third interval threshold as the start time, until the transit end time of the second satellite is reached;

[0128] Sub-step D4: If not, discard the data transmission task of the second satellite.

[0129] In another specific implementation of the present invention, step 103 may further include:

[0130] Sub-step E1: When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the complete transit arc.

[0131] Sub-step E2: Starting from the transit start time of the first satellite, receive the data transmission task from the first satellite until the end time is reached, with the difference between the transit start time of the second satellite and the third interval threshold as the end time.

[0132] In this embodiment, when satellite A has a higher priority than satellite B, satellite A will receive the complete data transmission resources. Then, it is determined whether the time interval between a2 and b2 satisfies 270s. If it does, data reception from satellite B begins at (a2+270s) and stops at time b2. If it does not satisfy the time interval, satellite B's data transmission task is discarded. When satellite A has a lower priority than satellite B, satellite B will receive the complete data transmission resources; satellite A starts receiving data at time a1 and stops at (b1-270s).

[0133] After constructing a non-mutually exclusive chain based on satellite priority, several feasible ground station transit time allocation schemes are obtained within the planned time period. Then, among these schemes, the optimal planning scheme is selected based on the satellite resource duration and the importance of the demand. Based on this idea, by reading the transit window file generated by Module 1, each satellite and its corresponding transit windows with transit conflicts can be sequentially filtered out. Conflicts between satellites can be resolved according to a priority strategy. Finally, the results are displayed in the UI interface using the interconnection function between STK and Matlab.

[0134] The conflict-passing algorithm based on satellite priority and non-mutually exclusive chains prioritizes satellites during implementation, ensuring complete reception of data transmission resources from higher-priority satellites while shortening the transit times of conflicting lower-priority satellites. For critical or emergency tasks, complete downlink transmission is guaranteed, reflecting the "satellite priority" principle. In a downlink link generated by this method, the time interval between satellites transiting at the same time will be greater than 270 seconds, eliminating conflicts—a "non-mutually exclusive chain." However, in actual satellite imaging mission planning, satellite priorities are not static, and daily transit times vary slightly depending on satellite imaging strategies. Therefore, the output results need to be verified or fine-tuned based on the specific needs of the day to maximize the utilization of satellite and ground resources. Daily plans are sorted in descending order of benefit score, and the plan with the highest benefit score is displayed in the UI as a selection criterion for users' mission planning.

[0135] The specific embodiments described in this application are intended to enable those skilled in the art to gain a more comprehensive understanding of this application, but do not limit this application in any way. Therefore, those skilled in the art should understand that modifications or equivalent substitutions can still be made to this application; and all technical solutions and improvements that do not depart from the spirit and technical essence of this application should be covered within the scope of protection of this patent application.

[0136] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A ground station transit conflict resolution method, applied to a ground station transit conflict resolution system, characterized in that, The method includes: Based on the satellite's orbital elements and the ground station's geographic information parameters, a simulation scenario of the satellite and ground station is established in the STK software. The time for the satellite's nadir point trajectory to enter and exit the ground station is calculated and displayed in the user interface. For each satellite, a set of satellites that have transit conflicts with it and a set of conflict time periods are generated. Based on the time interval of adjacent reception tasks of ground reception resources, the conflict time periods are truncated according to the satellite priority allocation strategy. For each satellite, a set of non-conflicting transit times is generated and displayed in the user operation interface. Based on satellite priority, a non-mutually exclusive chain is constructed for the satellite transit time set. Several feasible ground station transit time allocation schemes are then used to calculate observation benefits, resulting in the optimal planning scheme, including: When the priority of the first satellite is higher than that of the second satellite, the first satellite is controlled to receive data transmission resources for the entire transit arc. Determine whether the time interval between the overpass start time of the first satellite and the overpass start time of the second satellite is greater than a first interval threshold. If so, the receiving task of the second satellite is completed within the time period from the start time of the second satellite's transit to the time difference between the start time of the first satellite's transit and the first interval threshold; otherwise, the data transmission task of the second satellite is discarded. When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the entire transit arc. Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than the first interval threshold. If so, the data transmission task of the first satellite is received from the sum of the transit end time of the second satellite and the first interval threshold, starting from the transit end time of the first satellite; otherwise, the data transmission task of the first satellite is discarded.

2. The method according to claim 1, characterized in that, The process of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes to obtain the optimal planning scheme, also includes: When the priority of the first satellite is higher than that of the second satellite, control the first satellite to receive data transmission resources for the entire transit arc. Determine whether the time interval between the transit start time of the first satellite and the transit start time of the second satellite is greater than a second interval threshold. If so, the receiving task of the second satellite is completed from the start time of the second satellite's transit to the start time of the first satellite's transit minus the second interval threshold. If not, then the data transmission task of the second satellite will be abandoned; Again, determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than the second interval threshold. If so, then the data transmission task of the second satellite will be received starting from the end time of the first satellite's transit plus the second interval threshold, until the end time of the second satellite's transit. If not, then the second satellite's subsequent data transmission task will be abandoned.

3. The method according to claim 2, characterized in that, The process of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes to obtain the optimal planning scheme, also includes: When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the entire transit arc. Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than a second interval threshold. If so, the data transmission task of the first satellite is received starting from the sum of the transit end time of the second satellite and the second interval threshold, until the transit end time of the first satellite is reached. If not, then the data transmission task of the first satellite will be abandoned.

4. The method according to claim 1, characterized in that, The process of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes to obtain the optimal planning scheme, also includes: When the priority of the first satellite is higher than that of the second satellite, control the first satellite to receive data transmission resources for the entire transit arc. Determine whether the time interval between the overpass end time of the first satellite and the overpass end time of the second satellite is greater than a third interval threshold. If so, the data from the second satellite is received starting from the sum of the transit end time of the first satellite and the third interval threshold, until the transit end time of the second satellite is reached. If not, discard the data transmission task of the second satellite.

5. The method according to claim 4, characterized in that, The process of constructing a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculating the observation benefits of several feasible ground station transit time allocation schemes to obtain the optimal planning scheme, also includes: When the priority of the first satellite is lower than that of the second satellite, control the second satellite to receive data transmission resources for the entire transit arc. Starting from the transit start time of the first satellite, the data transmission task of the first satellite is received until the end time is reached, which is the difference between the transit start time of the second satellite and the third interval threshold.

6. The method according to claim 1, characterized in that, The ground station transit conflict resolution system includes: a transit analysis module, a conflict analysis module, and a solution generation module, wherein... The transit analysis module is configured to establish a simulation scenario of the satellite and ground station in the STK software based on the satellite's orbital elements and the geographic information parameters of the ground station, calculate the time for the satellite's nadir point trajectory to enter and exit the ground station, and display it in the user interface. The conflict analysis module is configured to generate a set of satellites that have transit conflicts with each satellite and a set of conflict time periods for each satellite. Based on the time interval of adjacent reception tasks of ground reception resources, the conflict time periods are truncated according to the satellite priority allocation strategy. A set of non-conflicting transit times is generated for each satellite and displayed in the user interface. The scheme generation module is configured to construct a non-mutually exclusive chain of satellite transit time sets based on satellite priority, calculate the observation benefits of several feasible ground station transit time allocation schemes, and obtain the optimal planning scheme.

7. The method according to claim 6, characterized in that, The transit analysis module is also configured to use Matlab software to interconnect with STK software, and to create a simulation scenario of the satellite and ground station in STK software based on the satellite's orbital elements and the geographic information parameters of the ground station.

8. The method according to claim 6, characterized in that, The conflict analysis module is also configured to determine the satellites whose transit times overlap based on the arc segments of each satellite passing over the ground station, and generate a set of satellites that have transit conflicts with each satellite and a set of conflict time periods for each satellite.

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