Emplacement resolving method and system based on elevation geographic data assistance

Abstract

The invention relates to an emplacement resolving method and system based on elevation geographic data assistance, and relates to the technical field of trajectory extrapolation of emplacement reconnaissance and radars. The method comprises the following steps: analyzing a geographic information file and storing elevation geographic data; the radar measurement data of the ballistic target is used, and based on the ballistic target motion model and the UKF filtering algorithm, smoothing processing of the ballistic target is completed; trajectory extrapolation is carried out based on a smoothing result and a trajectory target motion model, and estimated emplacement coordinates are obtained; based on the estimated emplacement coordinates, obtaining the average altitude at the estimated emplacement coordinates from the elevation geographic data by adopting a distance weighted average method; and judging whether the emplacement height is further extrapolated or not based on the difference between the average altitude and the emplacement height, and taking the result of the last extrapolation as the estimated emplacement coordinate. Compared with a traditional fitting method, the method has better estimation precision, and has more realistic significance for improving the emplacement calculation precision of the emplacement detection and calibration radar.

Description

Technical Field

[0001] The invention relates to the technical field of trajectory extrapolation of artillery position reconnaissance and calibration radar, and in particular to a method and system for calculating artillery position based on the assistance of elevation geographic data. Background Art

[0002] Artillery still plays a pivotal role in current applications, especially in local environments or small-scale use. Therefore, how to quickly detect the projectile targets fired by the opponent in a complex use environment and accurately locate the opponent's firing position is an important part of countering artillery, which is also one of the key technologies of artillery position reconnaissance and calibration radar.

[0003] According to the principle of ballistic motion, if the motion equation of the projectile target can be accurately obtained, the motion state and related parameters of the projectile target can be obtained by solving the differential equation according to the radar measurement data. However, this requires a large amount of prior data, which is impossible to achieve in practice. The current methods are as follows: First, the least squares fitting method is used to perform polynomial fitting on the ballistic curve, and the launch point coordinates of the projectile are obtained by estimating the curve parameters; the second is the Kalman filter algorithm based on the ballistic target motion model, which uses radar measurement data to identify and estimate the target motion state and parameters, and then estimates the gun position based on the ballistic target model; the third is the gun position estimation method based on the machine learning algorithm, which is based on the principle of using prior sample data to perform statistical training on the established ballistic model, and then complete the target launch point estimation based on the training results. Among these three types of algorithms, the first type of method is simple to calculate, but it is easily affected by singular values ​​when the amount of data is small, so the obtained results are very different from the actual results; the second type of method has good real-time performance and estimation accuracy, and is not easily affected by wild value data. It is increasingly used in engineering. The present invention will also use the more accurate UKF filtering algorithm to estimate the gun position; the third type of method is difficult to apply to practical applications because it is difficult to obtain a large number of accurate training samples.

[0004] In practical applications, due to the uncertainty of the terrain where artillery is used, it is impossible to obtain the altitude of the projectile launching position in advance. Especially in border conflicts, the altitude fluctuations of the artillery position may be greater, and different artillery position altitudes will have a greater impact on the results of trajectory extrapolation.

[0005] At present, there are many reports on methods of estimating gun position based on projectile measurement data in the literature. For example, (1) the publication number is CN105589068B, and the name is: a trajectory extrapolation method based on three-step numerical integration, using the already formed ballistic trajectory; (2), Yan Jun, Liu Qitao, Research on high-precision trajectory extrapolation technology for gun position detection radar, Journal of Artillery Launch and Control, 2022, 43(3); (3), Wang Gan, Xiong Feng, Ou Nengjie, et al. Trajectory extrapolation algorithm based on inverse extended Kalman filter, Electro-Optics and Control, 2020, 27(12). (4), Yuan Guiqi, Application of Geographic Information System in Gun Position Detection Radar [M], Nanjing University of Science and Technology, 2013. Literature (1) uses a three-step numerical integration method to extrapolate the starting point of the projectile; however, this method requires trajectory correction to form a flight trajectory to obtain better accuracy, and it may be difficult to obtain sufficient measurement data in practice. Reference (2) models the ballistic target and compares and analyzes different extrapolation algorithms such as least squares and Kalman filtering. Reference (3) proposes a trajectory extrapolation algorithm based on inverse extended Kalman filtering to address the problem of gun position estimation error caused by far-point extrapolation in the existing trajectory extrapolation algorithm of gun position reconnaissance radar. However, the algorithms in references (2) and (3) do not support the use of Doppler radial velocity information. Reference (4) studies the application integration and display of geographic information system and gun position reconnaissance radar, but does not combine elevation information with the gun position estimation algorithm.

[0006] In the current literature, in the problem of gun position estimation for gun position detection and calibration radar, no research has been found on the use of elevation geographic information and UKF filtering algorithm to estimate gun position coordinates. Summary of the invention

[0007] The technical problems to be solved by the present invention are:

[0008] In order to avoid the shortcomings of the prior art, the present invention provides a gun position solution method and system based on the assistance of elevation geographic data. The elevation geographic data is used to solve the technical problem that the existing method does not take into account the gun position altitude, resulting in a large impact on the gun position accuracy estimation error in practical applications.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] A gun position calculation method based on elevation geographic data assistance, characterized by comprising:

[0011] Parse geographic information files and store elevation geographic data, including longitude, latitude, and altitude;

[0012] Parse and obtain the radar measurement data of the ballistic target, and complete the smoothing of the ballistic target based on the ballistic target motion model and UKF filtering algorithm;

[0013] Based on the smoothed results and the ballistic target motion model, the trajectory is extrapolated to obtain the estimated gun position coordinates; based on the estimated gun position coordinates, the distance-weighted average method is used from the elevation geographic data to obtain the average altitude at the estimated gun position coordinates; based on the difference between the average altitude and the gun position height, it is determined whether to further extrapolate the gun position height, and the result of the last extrapolation is used as the estimated gun position coordinates.

[0014] A further technical solution of the present invention: the method of parsing the geographic information file and storing the elevation geographic data comprises:

[0015] In geographic information files, the "longitude-latitude" plane is divided into a grid and stored in a matrix structure, with each grid vertex corresponding to a different altitude.

[0016] A further technical solution of the present invention: the radar measurement data includes distance, azimuth, pitch, or distance, azimuth, pitch and Doppler radial velocity.

[0017] A further technical solution of the present invention is: the method of obtaining the average altitude of the estimated gun position coordinates by using the distance weighted average method from the elevation geographic data based on the gun position height comprises:

[0018] Get the longitude, latitude and altitude of the estimated gun position coordinates express;

[0019] Calculate the average altitude of the estimated gun position coordinates using the distance weighted average method from the elevation geographic data The calculation formula is: Where (h1,h2,h3,h4) is The heights of the four vertices of the grid, (d1, d2, d3, d4) are The distances to the four vertices.

[0020] A further technical solution of the present invention: the step of determining whether to further extrapolate the gun position height based on the difference between the average altitude and the gun position height comprises:

[0021] When the difference between the average altitude and the gun position height is greater than the threshold value, the average altitude is used as the gun position height for the next extrapolation, and the trajectory extrapolation calculation is performed again until the difference between the average altitude and the gun position height is less than the threshold, then the iteration is terminated.

[0022] A further technical solution of the present invention includes an elevation data analysis and storage module, a measurement data analysis and filtering module, and an iterative solution module;

[0023] The elevation data parsing and storage module is used to parse geographic information files and store elevation geographic data, and the stored data includes longitude, latitude, and altitude;

[0024] The measurement data parsing and filtering module is used to parse and obtain the radar measurement data of the ballistic target, and complete the smoothing of the ballistic target based on the ballistic target motion model and UKF filtering algorithm;

[0025] The iterative solution module performs trajectory extrapolation based on the smoothed result and the ballistic target motion model to obtain estimated gun position coordinates; obtains the average altitude at the estimated gun position coordinates from the elevation geographic data using the distance weighted average method based on the estimated gun position coordinates; determines whether to further extrapolate the gun position height based on the difference between the average altitude and the gun position height, and uses the result of the last extrapolation as the estimated gun position coordinates.

[0026] A further technical solution of the present invention: the step of determining whether to further extrapolate the gun position height based on the difference between the average altitude and the gun position height comprises:

[0027] When the difference between the average altitude and the gun position height is greater than the threshold value, the average altitude is used as the gun position height for the next extrapolation, and the trajectory extrapolation calculation is performed again until the difference between the average altitude and the gun position height is less than the threshold, then the iteration is terminated.

[0028] A computer system, characterized in that it comprises: one or more processors, and a computer-readable storage medium for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the above-mentioned method.

[0029] A computer-readable storage medium, characterized in that it stores computer-executable instructions, which are used to implement the above method when executed.

[0030] A computer program product, characterized by comprising computer executable instructions, wherein the instructions are used to implement the above method when executed.

[0031] The beneficial effects of the present invention are:

[0032] The present invention provides a method and system for calculating gun positions based on the assistance of elevation geographic data, which parses geographic information files and stores elevation geographic data; parses and obtains radar measurement data of ballistic targets, and completes smoothing of ballistic targets based on ballistic target motion models and UKF filtering algorithms; performs trajectory extrapolation based on the smoothed results and the ballistic target motion model to obtain estimated gun position coordinates, and uses the "distance weighted average method" from the elevation geographic data to obtain the average altitude at the estimated gun position coordinates; when the difference between the estimated height and the average height is greater than a threshold, the average height is used as the gun position height for the next extrapolation, and the trajectory extrapolation calculation is performed again until the difference is less than a threshold, then the iteration is terminated, and the result of the last extrapolation is used as the estimated gun position coordinates. Compared with the prior art, it has the following advantages:

[0033] 1. The present invention calculates the gun position based on the ballistic target motion model and the UKF filtering algorithm, and can utilize more measurement data such as distance, azimuth, elevation and Doppler radial velocity, and has better estimation accuracy than the traditional fitting method;

[0034] 2. The present invention also uses elevation geographic data to assist in trajectory extrapolation, which is particularly suitable for real environments with large altitude fluctuations, and has more practical significance for improving the accuracy of gun position calculation of gun position detection radar. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0036] Figure 1 A block diagram of a gun position calculation method based on elevation geographic data assistance according to an embodiment of the present invention;

[0037] Figure 2 The present invention is a block diagram of a gun position solution system based on the assistance of elevation geographic data according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0039] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0040] The present invention proposes a gun position solution method based on the assistance of elevation geographic data. The method performs gun position solution based on a ballistic target motion model and a UKF filtering algorithm, and can utilize more measurement data such as distance, azimuth, pitch, and Doppler radial velocity. Compared with traditional fitting methods, the method has better estimation accuracy. At the same time, the method utilizes elevation geographic data to assist in trajectory extrapolation, and has better adaptability in a real environment with large altitude fluctuations. This method has more practical significance for improving the gun position estimation accuracy of a gun position detection and calibration radar.

[0041] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0042] The embodiment of the present invention provides a method for calculating gun position based on the assistance of elevation geographic data, comprising:

[0043] S1, parsing geographic information files and storing elevation geographic data, the stored data includes longitude, latitude, and altitude;

[0044] S2, parsing and acquiring the radar measurement data of the ballistic target, and completing the smoothing of the ballistic target based on the ballistic target motion model and UKF filtering algorithm;

[0045] S3, based on the smoothed result and the ballistic target motion model, the trajectory is extrapolated to obtain the estimated gun position coordinates (where the height is The average altitude of the estimated gun position coordinates is obtained by using the “distance weighted average method” from the elevation geographic data (expressed as indicates); when and When the difference is greater than the threshold value, As the gun position height for the next extrapolation, recalculate the trajectory until and If the difference is less than the threshold, the iteration is terminated and the result of the last extrapolation is used as the estimated gun position coordinates.

[0046] The following is a detailed description of each step:

[0047] In step S1, the geographic information file is parsed and the elevation geographic data is stored, and the stored data includes longitude, latitude, and altitude. The specific implementation process is as follows:

[0048] In the geographic information file, the "longitude-latitude" plane is divided into a grid and stored in a matrix structure. Each grid vertex corresponds to a different altitude. The stored elevation geographic number is denoted as H ij , subscript i is the index of longitude, subscript j is the index of latitude, and the height corresponding to each vertex is recorded as h ij .

[0049] In step S2, the radar measurement data of the ballistic target is parsed and obtained, and the smoothing of the ballistic target is completed based on the ballistic target motion model and UKF filtering algorithm. The specific implementation process is as follows:

[0050] In the embodiment of the present invention, the ballistic target motion model adopts the projectile center of mass motion equation under non-standard ballistic conditions and non-standard meteorological conditions established in "Ballistic Solution Theory and Application, Zhao Xinsheng, Shu Jingrong, 2006".

[0051] The measurement data includes distance, azimuth, pitch and Doppler radial velocity, with a data rate of 2Hz and a duration of 15 seconds. The measurement noise is 50 meters, 0.1 degrees, 0.1 degrees, and 10m / s. The measurement model with Doppler radial velocity is:

[0052]

[0053] The state X k is 7-dimensional, including position (x k ,y k ,z k ),speed and ballistic coefficient C b .

[0054] UKF filtering is used to filter the measured data in "time reverse order" to obtain the state estimate at the first point. In the UKF filter, the process noise is: Q=diag([1e1,1e1,1e1,1e-2,1e-2,1e-2,0]), and the initial value of the ballistic coefficient is 0.6.

[0055] In step S3, the trajectory is extrapolated based on the smoothed result and the ballistic target motion model to obtain the estimated gun position coordinates (where the height is expressed as The average altitude of the estimated gun position coordinates is obtained by using the “distance weighted average method” from the elevation geographic data (expressed as indicates); when and When the difference is greater than the threshold value, As the gun position height for the next extrapolation, recalculate the trajectory until and If the difference is less than the threshold, the iteration is terminated and the result of the last extrapolation is used as the estimated gun position coordinates. The specific implementation process is as follows:

[0056] (1) Estimating the state based on the first point and the ballistic target motion model, the fourth-order Runge-Kutta method is used for extrapolation, the extrapolation step is set to 0.1s, and the end height h is set stop (The first extrapolation is set to 0), when the height is less than h during extrapolation stop When , the extrapolation is terminated, and the estimated latitude and longitude of the gun position are

[0057] (2) From the elevation geographic data H ij Search The four vertices of the grid are H1, H2, H3, and H4. The corresponding average height is: Where (h1,h2,h3,h4) are the heights of the four vertices H1,H2,H3,H4, and (d1,d2,d3,d4) are The distances to the four vertices.

[0058] (3) Repeat the above steps (1) and (2). and When the difference is less than 100 meters, the iteration is terminated and the result of the last extrapolation is used as the estimated gun position coordinates.

[0059] After simulation analysis, the simulation conditions are: the radar station is 20km away from the gun launch point, the elevation angle of the first detection point is 5 degrees, the gun position estimation error is 25.467 meters, and the estimation accuracy is about 1.25‰.

[0060] The embodiment of the present invention also provides a gun position solution system based on the assistance of elevation geographic data, the system comprising: an elevation data analysis and storage module, a measurement data analysis and filtering module, and an iterative solution module;

[0061] The elevation data parsing and storage module is used to parse geographic information files and store elevation geographic data, and the stored data includes longitude, latitude, and altitude;

[0062] The measurement data parsing and filtering module is used to parse and obtain the radar measurement data of the ballistic target, and complete the smoothing of the ballistic target based on the ballistic target motion model and UKF filtering algorithm;

[0063] The iterative solution module performs trajectory extrapolation based on the smoothed result and the ballistic target motion model to obtain the estimated gun position coordinates (where the height is expressed as The average altitude of the estimated gun position coordinates is obtained by using the “distance weighted average method” from the elevation geographic data (expressed as indicates); when and When the difference is greater than the threshold value, As the gun position height for the next extrapolation, recalculate the trajectory until and If the difference is less than the threshold, the iteration is terminated and the result of the last extrapolation is used as the estimated gun position coordinates.

[0064] It can be understood that the gun position solution system based on the assistance of elevation geographic data provided in an embodiment of the present invention corresponds to the above-mentioned gun position solution method based on the assistance of elevation geographic data, and the explanations, examples, beneficial effects and other parts of its relevant contents can refer to the corresponding contents in the gun position solution method based on the assistance of elevation geographic data, which will not be repeated here.

[0065] The present invention performs gun position solution based on the ballistic target motion model and the UKF filtering algorithm, and can utilize more measurement data such as distance, azimuth, pitch and Doppler radial velocity. Compared with the traditional fitting method, it has better estimation accuracy and utilizes elevation geographic data to assist in trajectory extrapolation. It is particularly suitable for real environments with large altitude fluctuations, and has more practical significance for improving the gun position solution accuracy of gun position detection and calibration radar.

[0066] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims

1. A gun position calculation method based on elevation geographic data, characterized in that: include: Parse geographic information files and store elevation geographic data, including longitude, latitude, and altitude; Parse and obtain the radar measurement data of the ballistic target, and complete the smoothing of the ballistic target based on the ballistic target motion model and UKF filtering algorithm; Based on the smoothed result and the ballistic target motion model, the trajectory is extrapolated to obtain the estimated gun position coordinates; based on the estimated gun position coordinates, the distance weighted average method is used from the elevation geographic data to obtain the average altitude at the estimated gun position coordinates; Based on the difference between the average altitude and the gun position height, it is determined whether to further extrapolate the gun position height, and the result of the last extrapolation is used as the estimated gun position coordinates.

2. The method for calculating gun positions based on elevation geographic data assistance according to claim 1 is characterized in that: The method of parsing the geographic information file and storing the elevation geographic data includes: In geographic information files, the "longitude-latitude" plane is divided into grids and stored in a matrix structure, with each grid vertex corresponding to a different altitude.

3. The method for calculating gun positions based on elevation geographic data assistance according to claim 1 is characterized in that: The radar measurement data includes range, azimuth, elevation, or range, azimuth, elevation and Doppler radial velocity.

4. The method for calculating gun positions based on elevation geographic data assistance according to claim 2 is characterized in that: The method of obtaining the average altitude at the estimated gun position coordinates by using the distance weighted average method from the elevation geographic data based on the gun position height includes: Get the longitude, latitude and altitude of the estimated gun position coordinates express; Calculate the average altitude of the estimated gun position coordinates using the distance weighted average method from the elevation geographic data The calculation formula is: Where (h1,h2,h3,h4) is The heights of the four vertices of the grid, (d1, d2, d3, d4) are The distances to the four vertices.

5. The method for calculating gun positions based on elevation geographic data assistance according to claim 1 is characterized in that: The step of determining whether to further extrapolate the gun position height based on the difference between the average altitude and the gun position height comprises: When the difference between the average altitude and the gun position height is greater than the threshold value, the average altitude is used as the gun position height for the next extrapolation, and the trajectory extrapolation calculation is performed again until the difference between the average altitude and the gun position height is less than the threshold, then the iteration is terminated.

6. The gun position calculation system based on elevation geographic data assistance according to claim 1 is characterized in that: It includes elevation data analysis and storage module, measurement data analysis and filtering module, and iterative solution module; The elevation data parsing and storage module is used to parse geographic information files and store elevation geographic data, and the stored data includes longitude, latitude, and altitude; The measurement data parsing and filtering module is used to parse and obtain the radar measurement data of the ballistic target, and complete the smoothing of the ballistic target based on the ballistic target motion model and UKF filtering algorithm; The iterative solution module performs trajectory extrapolation based on the smoothed result and the ballistic target motion model to obtain the estimated gun position coordinates; based on the estimated gun position coordinates, the distance weighted average method is used to obtain the average altitude at the estimated gun position coordinates from the elevation geographic data; Based on the difference between the average altitude and the gun position height, it is determined whether to further extrapolate the gun position height, and the result of the last extrapolation is used as the estimated gun position coordinates.

7. The gun position calculation system based on elevation geographic data assistance according to claim 6 is characterized in that: The step of determining whether to further extrapolate the gun position height based on the difference between the average altitude and the gun position height comprises: When the difference between the average altitude and the gun position height is greater than the threshold value, the average altitude is used as the gun position height for the next extrapolation, and the trajectory extrapolation calculation is performed again until the difference between the average altitude and the gun position height is less than the threshold, then the iteration is terminated.

8. A computer system, characterized in that include: One or more processors, and a computer-readable storage medium for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the method described in any one of claims 1-5.

9. A computer-readable storage medium, characterized in that Computer executable instructions are stored, and when the instructions are executed, they are used to implement the method according to any one of claims 1 to 5.

10. A computer program product, characterized in that The method comprises computer executable instructions, which are used to implement the method according to any one of claims 1 to 5 when being executed.

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