Satellite system task planning method for multi-target searching and tracking

Abstract

The invention provides a satellite system task planning method for multi-target searching and tracking, which comprises the following steps: acquiring task basic information which comprises satellite equipment information, target information and task termination time; determining the number of work tasks needing to be planned currently according to the task basic information; constructing a distribution benefit score function based on the frequency domain coverage condition of the satellite equipment on the target working frequency and the importance of the target in the area within the coverage range of the satellite equipment; determining an optimal beam position scheduling sequence of the target tracking task by maximizing the total beam position scheduling benefit of all the work tasks needing to be planned based on the benefit scoring function; and on the basis of the optimal beam position scheduling sequence, carrying out beam position scheduling in sequence. By adopting the method, the satellite beam position scheduling efficiency can be improved, and multi-target searching and tracking beam position scheduling planning can be efficiently completed.

Description

Technical Field

[0001] This invention relates to the field of satellite equipment system mission planning and resource management technology, and more specifically, to a satellite system mission planning method for multi-target search and tracking. Background Technology

[0002] With the continuous advancement of aerospace technology and the increasing complexity of satellite system application scenarios, the demand for onboard autonomous mission planning is growing. In complex and dynamic environments, achieving efficient autonomous mission planning is a crucial prerequisite for maximizing satellite system performance. Multi-target search and tracking tasks are often complex and diverse. Because the environment is typically dynamic, the position, number, and priority of targets can change at any time. Satellites need to complete the search and tracking of multiple targets within limited resources and time, and traditional static mission planning methods are insufficient to meet these application requirements.

[0003] Despite some progress in onboard autonomous mission planning in recent years, achieving efficient and reliable mission planning in complex and dynamic environments remains a pressing issue. Due to the multiple challenges faced by satellites, including high real-time requirements, significant environmental uncertainties, and diverse mission objectives, existing planning methods still have limitations in addressing rapidly changing target states, dynamically adjusting mission priorities, and optimizing resource allocation. Particularly in multi-target search and tracking missions, coordinating the handling of conflicts between multiple tasks, avoiding resource waste, and improving planning efficiency remain key challenges restricting satellite system performance improvement. Furthermore, hardware limitations such as satellite computing power further exacerbate the complexity of mission planning. While current research has proposed solutions based on artificial intelligence and optimization algorithms to some extent, these issues still require further breakthroughs in practical applications to meet the demands of future, more complex space missions. Therefore, the dynamism and autonomy of onboard mission planning remain a significant and urgent problem to be solved. Summary of the Invention

[0004] The present invention aims to solve at least one of the aforementioned technical problems existing in the prior art.

[0005] Therefore, this invention provides a satellite system mission planning method for multi-target search and tracking.

[0006] The satellite system mission planning method for multi-target search and tracking proposed in this invention includes: Obtain basic mission information, including satellite equipment information, target information, and mission termination time; The number of work tasks that need to be planned at present is determined based on the aforementioned basic task information; A score function for allocation benefits is constructed based on the frequency domain coverage of the target by the satellite equipment and the importance of the target in the area within the coverage range of the satellite equipment. Based on the aforementioned benefit score function, the optimal wave position scheduling order of the target tracking task is determined by maximizing the total wave position scheduling benefit of all planned tasks. Based on the optimal wave position scheduling order, wave positions are scheduled sequentially.

[0007] The satellite system mission planning method for multi-target search and tracking according to the above-described technical solution of the present invention may also have the following additional technical features: In the above technical solution, the satellite equipment information includes: the operating frequency range of the satellite equipment, the scanning range coverage angle, the beam dwell time, the position information, the speed information, and the attitude information; The target information includes the operating frequency, location coordinates, and target priority of M targets.

[0008] In the above technical solution, when M is 0, target search is performed, receiving new targets from other observation platforms, targets that are maintained for tracking locally, and new targets discovered by wavelet scanning search according to preset operating frequency and antenna direction. The new targets found are used as the target set for the next tracking task planning.

[0009] In the above technical solution, determining the number of work tasks to be planned based on the basic task information includes: Determine whether the mission termination time has been reached after all target tracking tasks have been completed based on the beam dwell time of the satellite equipment. like This will increase the number of tasks that need to be planned. Otherwise ; in, Indicates the current time; This indicates the number of targets in the target list; Indicates the beam dwell time of satellite equipment; Indicates the task termination time; This indicates rounding down to the nearest integer.

[0010] In the above technical solution, the allocation benefit scoring function is:

[0011] Indicates the future number Secondary wavelet scheduling is oriented towards the first The effectiveness score of each objective; Represents the frequency domain coverage characteristic function; Indicates the first The working frequency of each target; A function representing the importance of a region; Indicates the first The location coordinates of the target; Indicates the first The goal priority of each objective.

[0012] In the above technical solution, the frequency domain coverage indicator function is expressed as:

[0013] The region importance function is expressed as:

[0014] Where a and b are both variable indices; The operating frequency range of the satellite equipment; , and The importance coefficients are, in order, for important areas, general areas, and non-important areas within the instantaneous coverage range of the satellite, and satisfy the following conditions: .

[0015] In the above technical solution, determining the optimal wave position scheduling order for the target tracking task based on the benefit score function by maximizing the total wave position scheduling benefit of all planned tasks includes:

[0016] in, This indicates the number of work tasks that need to be planned at present; This indicates the number of targets in the target list; Represents the indicator variable to be optimized; Indicates a restriction condition.

[0017] In the above technical solution, maximizing the total slot scheduling benefit of all planned tasks is a two-dimensional allocation problem. An allocation algorithm is used to solve this two-dimensional allocation problem, and the optimal solution obtained is... That is, it has obtained the future orientation The optimal wave position scheduling order for a target tracking task, where Indicates the first wavelet scheduling facing the first wavelet. One goal.

[0018] In the above technical solution, the step of sequentially scheduling wave positions based on the optimal wave position scheduling order includes: Acquiring satellite equipment in Position information, velocity information, and attitude information at any given moment; Calculation in At what time, the location of the satellite equipment With the The direction vector corresponding to each target ; According to the direction vector Determine the first Off-axis angle of the target in the satellite body coordinate system and azimuth ; The first Frequency and off-axis angle of each target and azimuth As the current operating parameters of the satellite system, the [further details are needed]. Tracking of individual targets; Track all targets in the sequence according to the optimal wave position scheduling order.

[0019] In the above technical solutions, satellite equipment is in The position, velocity, and attitude information at any given moment are parameter information based on the WGS84 coordinate system; The first Off-axis angle of the target in the satellite body coordinate system and azimuth The calculation method is as follows:

[0020] in, This represents the rotation matrix used to transform the WGS84 coordinate system to the satellite orbit coordinate system. This represents the rotation matrix used to transform the satellite's orbital coordinate system to the satellite's body coordinate system. Direction vector Transform to vector representation in the satellite body coordinate system.

[0021] In summary, due to the adoption of the above-mentioned technical features, the beneficial effects of the present invention are: This invention calculates the efficiency score of satellite system slot scheduling for different targets by comprehensively considering information such as multi-target spatial domain, frequency domain, and priority. It transforms the slot scheduling task for multi-target search and tracking into a two-dimensional allocation problem, which can quickly solve for the optimal solution in polynomial time. Then, the optimal slot is selected according to the target order, thereby improving the efficiency of satellite slot scheduling and efficiently completing multi-target search and tracking slot scheduling planning.

[0022] Specifically, this invention calculates the score for wavelet scheduling towards different targets at different times using information such as multi-target spatial domain, frequency domain, and satellite status, fully utilizing the time-varying positional relationships between multiple targets and satellites in complex dynamic environments. This invention transforms the wavelet scheduling task of multi-target search and tracking into a two-dimensional allocation problem, enabling rapid solution of the optimal task planning in polynomial time, thereby significantly improving the efficiency of satellite systems in multi-target Earth observation tasks.

[0023] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart of a satellite system mission planning method for multi-target search and tracking according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the latitude and longitude of the simulated satellite trajectory during the simulation experiment of this invention; Figure 3 This is a schematic diagram of multiple target locations randomly generated during a Monte Carlo experiment in the simulation test of this invention; Figure 4 This is a schematic diagram showing the percentage improvement in the average efficiency of wave position scheduling of the method proposed in this invention compared to the comparative method during simulation experiments. Figure 5 This is a schematic diagram illustrating the average time consumption of single task planning under different target number scales during the simulation test of this invention. Detailed Implementation

[0025] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0026] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0027] The following reference Figures 1 to 5 This describes a satellite system mission planning method for multi-target search and tracking provided according to some embodiments of the present invention.

[0028] Some embodiments of this application provide a satellite system mission planning method for multi-target search and tracking.

[0029] like Figure 1 As shown, the first embodiment of the present invention proposes a satellite system mission planning method for multi-target search and tracking, including the following steps S1-S8.

[0030] S1. Obtain basic mission information, including satellite equipment information, target information, and mission termination time.

[0031] Specifically, the satellite equipment information includes: the operating frequency range of the satellite equipment. Scanning range coverage angle Beam dwell time Location information Speed ​​information and attitude information (yaw angle) Pitch angle and roll angle ); The target information includes the operating frequency, location coordinates, and target priority of M targets. Among them, the first... The working frequency of each target is The position coordinates in the WGS84 coordinate system are Target Priority .

[0032] It should be noted that the coordinate-related information obtained in step S1 is usually based on the WGS84 coordinate system.

[0033] Understandably, in practical applications, M should be an integer not less than 0, and the target number for each planning step can be less than M. The number of work tasks to be planned should be determined according to subsequent steps.

[0034] S2. Read the target information input by the system and add it to the target list. If the target list is not empty, that is, M is not equal to 0, then continue to execute the following step S3; otherwise, that is, when M=0, jump to step S7 and execute the target search mode. It is understood that, for the purposes of this disclosure, when there are multiple definite search targets, this judgment process and step S7 can be omitted.

[0035] S3. Determine the number of work tasks that need to be planned based on the basic task information.

[0036] In some embodiments, step S3 includes: Determine whether the mission termination time has been reached after performing all target tracking tasks based on the satellite equipment's beam dwell time; if... This will increase the number of tasks that need to be planned. Otherwise ;in, Indicates the current time; This indicates the number of targets in the target list; Indicates the beam dwell time of satellite equipment; Indicates the task termination time; This indicates rounding down to the nearest integer.

[0037] S4. Construct an allocation benefit score function based on the frequency domain coverage of the target's operating frequency by the satellite equipment and the importance of the area where the target is located within the coverage area of ​​the satellite equipment.

[0038] Specifically, the allocation benefit score function is:

[0039] Indicates the future number Secondary wavelet scheduling is oriented towards the first The effectiveness score of each objective. Indicates unassigned wavelet scheduling towards the first The effectiveness score of each objective. Indicates the future number The benefit score of secondary wavelet scheduling not being goal-oriented; Represents the frequency domain coverage characteristic function; Indicates the first The working frequency of each target; A function representing the importance of a region; Indicates the first The location coordinates of the target; Indicates the first The goal priority of each objective.

[0040] In one specific embodiment, the frequency domain coverage indicator function is expressed as:

[0041] The region importance function is expressed as:

[0042] Where a and b are both variable indices; , and The importance coefficients of the important areas, general areas, and non-important areas within the instantaneous coverage of the satellite are, in descending order, or are uniformly distributed and satisfy the following conditions: Among them, the important areas, general areas and non-important areas within the instantaneous coverage range of the satellite can be pre-defined.

[0043] S5. Based on the benefit score function, determine the optimal wave position scheduling order of the target tracking task by maximizing the total wave position scheduling benefit of all planned tasks.

[0044] Specifically, step S5 includes:

[0045] in, This indicates the number of work tasks that need to be planned at present; This indicates the number of targets in the target list; Represents the indicator variable to be optimized; Indicates a restriction condition.

[0046] As can be seen, the task allocation problem presents itself as a two-dimensional allocation problem. The optimal solution obtained by using an allocation algorithm to solve this two-dimensional allocation problem is: That is, it has obtained the future orientation The optimal wave position scheduling order for a target tracking task, where Indicates the first wavelet scheduling facing the first wavelet. One goal.

[0047] The allocation algorithm can employ an improved Jonker-Volgenant algorithm, and the computational complexity of the above optimization problem is O(n log n). The details of the Jonker–Volgenant algorithm can be found in the paper [DF Crouse, “On implementing 2D rectangular assignment algorithms,” IEEE Transactions on Aerospace and Electronic Systems, vol. 52, no. 4, pp. 1679–1696, 2016.]. Since the Jonker–Volgenant algorithm is well-known to those skilled in the art, it will not be elaborated upon here.

[0048] S6. Based on the optimal wave position scheduling order, wave positions are scheduled sequentially.

[0049] In some embodiments, step S6 includes the following steps S61-S65.

[0050] S61. Acquiring satellite equipment based on the WGS84 coordinate system. Position information, velocity information, and attitude information at any given moment.

[0051] S62, Calculation in At what time, the location of the satellite equipment With the The direction vector corresponding to each target Specifically:

[0052] in, Indicates the first The position of the target in the WGS84 coordinate system.

[0053] S63, based on the direction vector Determine the first Off-axis angle of the target in the satellite body coordinate system and azimuth .

[0054] Specifically, the first Off-axis angle of the target in the satellite body coordinate system and azimuth The calculation method is as follows:

[0055] in, This represents the rotation matrix used to transform the WGS84 coordinate system to the satellite orbit coordinate system. This represents the rotation matrix used to transform the satellite's orbital coordinate system to the satellite's body coordinate system. Direction vector Transform to vector representation in the satellite body coordinate system.

[0056] It should be noted that, and Requires satellite-based equipment The time corresponding ,speed Satellite equipment attitude information (yaw angle) Pitch angle and roll angle The calculation can be performed by referring to the method described in Chinese Invention Patent Application No. CN202411433952.2.

[0057] S64, the first Frequency and off-axis angle of each target and azimuth As the current operating parameters of the satellite system, the [further details are needed]. Tracking of individual targets.

[0058] S65. Following the optimal wave position scheduling order, track all targets in the sequence in that order. Specifically, update... as well as ,like If the result is positive, proceed to step S61 to continue execution; otherwise, proceed to step S7 to continue execution.

[0059] When S7 and M are 0, or after completing step S6, target search is performed. New targets from other observation platforms, targets that are being tracked locally, and new targets discovered by wavelet scanning search according to preset operating frequency and antenna direction are received. The new targets found are used as the target set for the next tracking task planning.

[0060] S8. Determine if the task termination time has been reached. If not, proceed to step S2 to continue execution; otherwise, the task ends.

[0061] In one specific embodiment, satellite trajectory data is generated by simulating the following satellite orbit parameters, and multiple targets with random operating frequencies and positions are generated within a given range. The algorithm of this invention is then used to process the data to obtain a multi-target-oriented task plan.

[0062] The comparison algorithm is as follows: For multi-target search and tracking task scenarios, this embodiment compares the task planning performance of scheduling in order of priority from high to low (hereinafter referred to as the comparison method) and the method proposed in this invention.

[0063] This example sub-simulation simulates a satellite orbit, generating satellite position and velocity information every second. The generated trajectory latitude and longitude are as follows: Figure 2 As shown, the circular and square markers represent the positions corresponding to the start and end times of the mission, respectively. Additionally, the satellite system operates within a frequency range of 2000MHz to 5000MHz. To verify the method's performance, comparative analyses were conducted under various target frequency / spatial distribution scenarios. Specifically, the region's center position was set at longitude 153°, latitude 22°, and width 20°. Multiple targets were uniformly generated within the region, with their operating frequencies randomly generated uniformly within the range of 2000MHz to 5500MHz (some targets' operating frequencies may not be within the satellite system's operating frequency range). Priorities were randomly generated uniformly within the range of 1 to 1000 (higher values ​​indicate higher priority). 500 Monte Carlo random experiments were conducted with the target number following a Poisson distribution with mean values ​​of 10, 20, ..., 200 (in increments of 10), and the average results were statistically analyzed. Furthermore, when calculating the wavelet scheduling gain score, the regional importance function... A uniform distribution is adopted. Figure 3 This is a diagram showing the locations of multiple targets randomly generated in a Monte Carlo experiment, where triangles represent targets.

[0064] Evaluation Metric: The percentage improvement in average wave position scheduling efficiency is used as the metric to evaluate the method's performance. Specifically, it is defined as follows: Let the average wave position scheduling efficiency of Algorithm 1 (the algorithm of this invention) and Algorithm 2 (the comparison algorithm) from the start to the end of the task be respectively... and ,in and They are algorithms l The total efficiency of wave position scheduling from start to finish, along with the number of wave position scheduling operations, is calculated. Therefore, the average efficiency improvement of Algorithm 1 compared to Algorithm 2 is [percentage missing]. .

[0065] Effect Analysis: Figure 4 The results of 500 Monte Carlo experiments demonstrate the percentage improvement in average position scheduling efficiency of the proposed method compared to the comparative method, as the mean of the Poisson distribution of the number of generated targets changes. In general, an increase in the number of targets leads to increased dynamics and complexity in multi-target search and tracking task planning. The proposed method dynamically considers spatial, frequency, and priority information of multiple targets, transforming the position scheduling task for multi-target search and tracking into a two-dimensional allocation problem. It can quickly solve for the optimal solution in polynomial time, significantly outperforming the comparative methods.

[0066] Figure 5 The average time consumed in a single mission planning operation by the proposed method under different target numbers is shown. The satellite system mission planning method for multi-target search and tracking proposed in this invention has advantages such as polynomial computational complexity, and can effectively solve the time-varying multi-target search and tracking problem in complex dynamic environments, and improve the efficiency of satellite systems in multi-target Earth observation missions.

[0067] In this specification, the illustrative expressions of the terms used do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0068] Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention shall be included within the scope of protection of this invention.

Claims

1. A satellite system mission planning method for multi-target search and tracking, characterized in that, include: Obtain basic mission information, including satellite equipment information, target information, and mission termination time; The number of work tasks that need to be planned at present is determined based on the aforementioned basic task information; A score function for allocation benefits is constructed based on the frequency domain coverage of the target by the satellite equipment and the importance of the target in the area within the coverage range of the satellite equipment. Based on the aforementioned benefit score function, the optimal wave position scheduling order of the target tracking task is determined by maximizing the total wave position scheduling benefit of all planned tasks. Based on the optimal wave position scheduling order, wave positions are scheduled sequentially.

2. The satellite system mission planning method for multi-target search and tracking according to claim 1, characterized in that, The satellite equipment information includes: the operating frequency range, scanning range coverage angle, beam dwell time, location information, speed information, and attitude information of the satellite equipment; The target information includes the operating frequency, location coordinates, and target priority of M targets.

3. The satellite system mission planning method for multi-target search and tracking according to claim 2, characterized in that, When M is 0, target search is performed. New targets from other observation platforms, targets maintained for local tracking, and new targets discovered by wavelet scanning search according to preset operating frequency and antenna direction are received. The new targets found are used as the target set for the next tracking task planning.

4. The satellite system mission planning method for multi-target search and tracking according to claim 2, characterized in that, The step of determining the number of work tasks to be planned based on the basic task information includes: Determine whether the mission termination time has been reached after all target tracking tasks have been completed based on the beam dwell time of the satellite equipment. like This will increase the number of tasks that need to be planned. Otherwise ; in, Indicates the current time; This indicates the number of targets in the target list; Indicates the beam dwell time of satellite equipment; Indicates the task termination time; This indicates rounding down to the nearest integer.

5. The satellite system mission planning method for multi-target search and tracking according to claim 2, characterized in that, The allocation benefit score function is: Indicates the future number Second wave scheduling is oriented towards the first The effectiveness score of each objective; Represents the frequency domain coverage characteristic function; Indicates the first The working frequency of each target; A function representing the importance of a region; Indicates the first The location coordinates of the target; Indicates the first The goal priority of each objective.

6. The satellite system mission planning method for multi-target search and tracking according to claim 5, characterized in that, The frequency domain coverage indicator function is expressed as follows: The region importance function is expressed as: Where a and b are both variable indices; The operating frequency range of the satellite equipment; , and The importance coefficients are, in order, for important areas, general areas, and non-important areas within the instantaneous coverage range of the satellite, and satisfy the following conditions: .

7. The satellite system mission planning method for multi-target search and tracking according to claim 6, characterized in that, The process of determining the optimal wave position scheduling order for the target tracking task based on the benefit score function by maximizing the total wave position scheduling benefit of all planned tasks includes: in, This indicates the number of work tasks that need to be planned at present; This indicates the number of targets in the target list; Represents the indicator variable to be optimized; Indicates a restriction condition.

8. The satellite system mission planning method for multi-target search and tracking according to claim 7, characterized in that, Maximizing the total slot scheduling efficiency for all planned tasks is a two-dimensional allocation problem. An allocation algorithm is used to solve this two-dimensional allocation problem, and the optimal solution obtained is... That is, it has obtained the future orientation The optimal wave position scheduling order for a target tracking task, where Indicates the first wavelet scheduling facing the first wavelet. One goal.

9. The satellite system mission planning method for multi-target search and tracking according to claim 8, characterized in that, The step of sequentially scheduling wave positions based on the optimal wave position scheduling order includes: Acquiring satellite equipment in Position information, velocity information, and attitude information at any given moment; Calculation in At what time, the location of the satellite equipment With the The direction vector corresponding to each target ; According to the direction vector Determine the first Off-axis angle of the target in the satellite body coordinate system and azimuth ; The first Frequency and off-axis angle of each target and azimuth As the current operating parameters of the satellite system, the [further details are needed]. Tracking of individual targets; Track all targets in the sequence according to the optimal wave position scheduling order.

10. The satellite system mission planning method for multi-target search and tracking according to claim 9, characterized in that, Satellite equipment in The position, velocity, and attitude information at any given moment are parameter information based on the WGS84 coordinate system; The first Off-axis angle of the target in the satellite body coordinate system and azimuth The calculation method is as follows: in, This represents the rotation matrix used to transform the WGS84 coordinate system to the satellite orbit coordinate system. This represents the rotation matrix used to transform the satellite's orbital coordinate system to the satellite's body coordinate system. Direction vector Transform to vector representation in the satellite body coordinate system.

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