A passive positioning method and system for radar emitter targets

Abstract

The embodiment of the present application provides a kind of passive positioning method and system for radar radiation source target, it is related to passive positioning method technical field, the method comprises: extracting a batch of the effective direction finding line data, using the longitude, latitude and direction angle vector of arrival, the intersection of every two the direction finding line is calculated, and the horizontal coordinate and vertical coordinate of the intersection are stored in intersection set;In the plane of the Cartesian coordinate system, a certain range is selected, according to threshold value, the range is evenly divided into several grid matrices, the grid matrix includes multiple grids, the grid includes multiple intersection sets;The density distribution information of intersection set in the grid matrix is counted;According to the density distribution information, find out the grid with maximum density.

Description

Technical Field

[0001] This invention relates to the field of passive positioning methods and systems, and in particular to a passive positioning method and system for radar radiation source targets. Background Technology

[0002] Passive positioning refers to a positioning method in which the observation station does not emit electromagnetic signals toward the target, but only receives electromagnetic signals radiated outward from the target, and uses the azimuth information contained in the target signals to calculate the target's location using observation data from multiple stations or points.

[0003] In modern warfare, when radar actively scans for targets, the radar signal can be easily intercepted by the enemy, leading to the exposure of the radar observation station. Therefore, in radar countermeasures, passive positioning technology is often used. This involves receiving electromagnetic signals emitted or reflected from the target, and the observation station uses the azimuth information of the received signal to determine the target's location through positioning technology.

[0004] Because they do not radiate electromagnetic signals, observation stations using passive positioning technology are difficult to detect, reducing the risk of destruction in war. Passive positioning is a widely used positioning technology in radar warfare.

[0005] Existing passive positioning technologies are mainly based on the least squares method or improved algorithms based on it. These methods are extremely sensitive to outlier data; when sorting results are incorrect or measurement errors are large, the positioning accuracy is poor. In practice, improving the accuracy of sorting results and reducing direction-finding errors are ongoing efforts by radar engineers. This indicates that the input data for positioning algorithms is not always favorable for least squares-based passive positioning technologies. Therefore, least squares-based positioning techniques typically cannot provide satisfactory positioning results. There are also positioning methods based on intersection clustering, but due to inherent problems with clustering algorithms, positioning in radar data processing, which can reach millions of pulses per second, usually takes a considerable amount of time, resulting in poor near-real-time positioning performance. In scenarios requiring rapid response, these methods often fail to meet practical needs.

[0006] In conclusion, in the struggle against radar threats, it is urgent to develop new technologies and methods to improve the passive positioning accuracy and speed of radar radiation source targets. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention proposes a passive localization method and system for radar radiation source targets. The technical solution adopted by this invention is as follows:

[0008] A passive method for locating radar radiation source targets includes the following steps:

[0009] Step 1: Acquire data from multiple direction finding lines and extract the longitude, latitude, and direction of arrival angle vector of the direction finding lines;

[0010] Step 2: Clean the data of the direction finding lines to remove invalid direction finding line data and obtain valid direction finding line data; determine whether the valid direction finding line data meets the positioning conditions. If yes, proceed to step 3; otherwise, terminate.

[0011] Step 3: Using the center position of the reconnaissance aircraft's flight path as the origin, project the longitude and latitude of the flight path corresponding to the effective direction finding data onto the Cartesian coordinate system to obtain multiple vectors;

[0012] Step 4: Transform the multiple vectors into multiple linear equations in the Cartesian coordinate system;

[0013] Step 5: Divide the multiple linear equations into several batches and calculate the intersection points of all linear equations in all batches, including: extracting a batch of linear equations, calculating the intersection points of every two linear equations, and storing the x-coordinate and y-coordinate of the intersection points into an intersection point set.

[0014] Step 6: Calculate the coordinates of the target based on the set of intersection points;

[0015] Step 7: Calculate the distance between the coordinates of the target and the equations of each line, and sort the distances.

[0016] Step 6 includes:

[0017] Step 61: Select the range involved by the intersection point in the plane of the Cartesian coordinate system, and divide the range into several grid matrices evenly according to a threshold. Each grid matrix includes multiple grids, and each grid includes multiple sets of intersection points. Statistically analyze the density distribution information of the intersection point sets within the grid matrix.

[0018] Step 62: Identify the grid with the highest density based on the density distribution information;

[0019] If there is only one grid with the highest density, then the center coordinates of that grid are used as the coordinates of the target, and the value of those coordinates is returned.

[0020] If there are multiple grids with the highest density, a target minimum distinguishing distance is pre-specified, and then the distance between every two grids with the highest density is calculated and compared with the target minimum distinguishing distance.

[0021] When the distance is greater than the minimum distinguishing distance of the target, the center coordinates of the two grids with the highest density are used as the coordinates of the target, and the value of the coordinates is returned;

[0022] When the distance is less than the minimum distinguishing distance of the target, the center coordinate of any grid with the highest density is taken as the coordinate of the target, and the value of that coordinate is returned;

[0023] The coordinates are the coordinates of the target.

[0024] The passive localization method for radar radiation source targets further includes:

[0025] Step 8: Summarize the coordinates of the target and the distance, and translate the coordinates of the target back into the latitude and longitude coordinates of the target;

[0026] Step 9: Display the latitude and longitude coordinates of a certain number of the targets.

[0027] The removal of invalid direction finding line data includes: determining the number of direction finding lines; when the number of direction finding lines is less than 2, the direction finding lines are invalid direction finding line data, and removing the invalid direction finding line data.

[0028] The removal of invalid direction finding line data further includes: determining whether the longitude or latitude of the direction finding line deviates from the center position of the reconnaissance aircraft track by more than 2 degrees; if so, the direction finding line is invalid direction finding line data and the invalid direction finding line data is removed.

[0029] In step 3, the longitude and latitude of the track corresponding to the effective direction finding line data are projected onto the Cartesian coordinate system. The projection method is used to store the projection center and store the longitude and latitude coordinates projected onto the Cartesian coordinate system into a linked list.

[0030] Step 5 further includes: using the intersection calculation module to calculate the intersection point of each of the two line equations, and storing the coordinates of the intersection point in a linked list.

[0031] Step 61 further includes: determining whether there are fewer than 3 intersection points in the intersection point set; if so, defining the range of all intersection points as the grid matrix; if not, dividing the Cartesian coordinate system plane into a 600*600 grid matrix with the midpoint of the reconnaissance aircraft track as the origin.

[0032] A passive positioning system for radar radiation source targets, the passive positioning system comprising:

[0033] The module includes: acquisition module, data cleaning module, projection module, distance calculation module, batch processing module for linear equations, intersection calculation module, intersection density distribution statistics module, positioning module, coordinate inversion module, and coordinate value selection module.

[0034] The acquisition module is used to acquire the data of the direction finding line;

[0035] The data cleaning module is used to remove invalid direction finding line data;

[0036] The projection module projects the longitude and latitude of the track corresponding to the effective direction finding data onto the Cartesian coordinate system.

[0037] The distance calculation module is used to calculate the distance between points and the distance between points and lines in the Cartesian coordinate system.

[0038] The linear equation batch processing module is used to process the linear equations in batches.

[0039] The intersection point calculation module is used to calculate the intersection points of the line equations;

[0040] The intersection density distribution statistics module calculates the density distribution information of the intersection set within the grid matrix.

[0041] The positioning module is used to find the grid with the highest density based on the density distribution information;

[0042] The coordinate inversion module is used to invert the coordinate values ​​of the target into the longitude and latitude coordinates of the target;

[0043] The coordinate value selection module is used to calculate the distance between the coordinate value of the target and each of the line equations, and to display the coordinate value of the target.

[0044] Technical effects of the present invention:

[0045] This invention provides a passive localization method and system for radar radiation source targets. It processes direction finding data in batches, providing one or more target localization results for each batch, and then summarizing the results to ultimately provide the localization results for one or more targets. Batch processing of direction finding data improves data processing capabilities, enabling near real-time localization results. While displaying the localization results, it also selectively displays several corresponding direction finding lines, providing visualization of the results. This invention uses a density-based localization method, which is insensitive to outliers, has a wider range of applications, and higher localization efficiency. Attached Figure Description

[0046] Figure 1 This is a flowchart illustrating a passive localization method for radar radiation source targets, provided in an embodiment of the present invention. Detailed Implementation

[0047] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0048] See Figure 1This invention provides a passive localization method for radar radiation source targets, comprising the following steps:

[0049] Step 1: Acquire data from multiple direction finding lines and extract the longitude, latitude, and direction of arrival angle vector of the direction finding lines;

[0050] Step 2: Clean the data of the direction finding lines to remove invalid direction finding line data and obtain valid direction finding line data; determine whether the valid direction finding line data meets the positioning conditions. If yes, proceed to step 3; otherwise, terminate.

[0051] Step 3: Using the center position of the reconnaissance aircraft's flight path as the origin, project the longitude and latitude of the flight path corresponding to the effective direction finding data onto the Cartesian coordinate system to obtain multiple vectors;

[0052] Step 4: Transform the multiple vectors into multiple linear equations in the Cartesian coordinate system;

[0053] Step 5: Divide the multiple linear equations into several batches and calculate the intersection points of all linear equations in all batches, including: extracting a batch of linear equations, calculating the intersection points of every two linear equations, and storing the x-coordinate and y-coordinate of the intersection points into an intersection point set.

[0054] Step 6: Calculate the coordinates of the target based on the set of intersection points;

[0055] Step 7: Calculate the distance between the coordinates of the target and the equations of each line, and sort the distances.

[0056] This invention provides a passive localization method and system for radar radiation source targets. It processes direction-finding line data in batches, dividing each batch of valid direction-finding line data into multiple batches of straight line equations. Based on the intersection points of these equations, multiple grid matrices are created, thereby providing localization results for one or more targets. The results from each batch are then summarized to finally provide the localization results (latitude and longitude coordinates) for one or more targets. Batch processing of direction-finding line data improves data processing capabilities, enabling near real-time localization results. Simultaneously with displaying the localization results, several corresponding direction-finding lines are selectively displayed, providing visualization of the results. This invention uses a density-based localization method, which is insensitive to outliers, has a wider applicability, and higher localization efficiency.

[0057] In the above embodiments, step 6 includes:

[0058] Step 61: Select the range involved by the intersection point in the plane of the Cartesian coordinate system, and divide the range into several grid matrices evenly according to a threshold. Each grid matrix includes multiple grids, and each grid includes multiple sets of intersection points. Statistically analyze the density distribution information of the intersection point sets within the grid matrix.

[0059] Step 62: Identify the grid with the highest density based on the density distribution information;

[0060] If there is only one grid with the highest density, then the center coordinates of that grid are used as the coordinates of the target, and the value of those coordinates is returned.

[0061] If there are multiple grids with the highest density, a target minimum distinguishing distance is pre-specified, and then the distance between every two grids with the highest density is calculated and compared with the target minimum distinguishing distance.

[0062] When the distance is greater than the minimum distinguishing distance of the target, the center coordinates of the two grids with the highest density are used as the coordinates of the target, and the value of the coordinates is returned;

[0063] When the distance is less than the minimum distinguishing distance of the target, the center coordinate of any grid with the highest density is taken as the coordinate of the target, and the value of that coordinate is returned;

[0064] The coordinates are the coordinates of the target.

[0065] In the above embodiments, 3. the passive localization method for radar radiation source targets according to claim 2, characterized in that it further includes:

[0066] Step 8: Summarize the coordinates of the target and the distance, and translate the coordinates of the target back into the latitude and longitude coordinates of the target;

[0067] Step 9: Display the latitude and longitude coordinates of a certain number of the targets.

[0068] In the above embodiments, 4. the passive positioning method for radar radiation source targets according to claim 1, characterized in that, the removal of invalid direction finding line data includes: determining the number of direction finding lines, and when the number of direction finding lines is less than 2, the direction finding lines are invalid direction finding line data, and removing the invalid direction finding line data.

[0069] In the above embodiments, 5. the passive positioning method for radar radiation source targets according to claim 4, characterized in that the removal of invalid direction finding line data further includes: determining whether the longitude or latitude of the direction finding line deviates from the center position of the reconnaissance aircraft track by more than 2 degrees; if so, the direction finding line is invalid direction finding line data, and the invalid direction finding line data is removed.

[0070] In the above embodiments, 6. The passive positioning method for radar radiation source targets according to claim 1 is characterized in that, in step 3, the longitude and latitude of the track corresponding to the effective direction finding line data are projected onto the Cartesian coordinate system, the projection center is stored using the projection method, and the longitude and latitude coordinates projected onto the Cartesian coordinate system are stored in a linked list.

[0071] In the above embodiments, 7. The passive positioning method for radar radiation source targets according to claim 1, wherein step 5 further includes: calculating the intersection point of each of the two line equations using the intersection point calculation module, and storing the coordinates of the intersection point in a linked list.

[0072] In the above embodiments, 8. the passive positioning method for radar radiation source targets according to claim 2, wherein step 61 further includes: determining whether there are fewer than 3 intersection points in the intersection point set; if so, defining the range involved by all the intersection points as the grid matrix; if not, dividing the plane of the Cartesian coordinate system into a 600*600 grid matrix with the midpoint of the reconnaissance aircraft track as the origin.

[0073] This invention also provides a passive positioning system for radar radiation source targets, the passive positioning system comprising:

[0074] The module includes: acquisition module, data cleaning module, projection module, distance calculation module, batch processing module for linear equations, intersection calculation module, intersection density distribution statistics module, positioning module, coordinate inversion module, and coordinate value selection module.

[0075] The acquisition module is used to acquire the data of the direction finding line;

[0076] The data cleaning module is used to remove invalid direction finding line data;

[0077] The projection module projects the longitude and latitude of the track corresponding to the effective direction finding data onto the Cartesian coordinate system.

[0078] The distance calculation module is used to calculate the distance between points and the distance between points and lines in the Cartesian coordinate system.

[0079] The linear equation batch processing module is used to process the linear equations in batches.

[0080] The intersection point calculation module is used to calculate the intersection points of the line equations;

[0081] The intersection density distribution statistics module calculates the density distribution information of the intersection set within the grid matrix.

[0082] The positioning module is used to find the grid with the highest density based on the density distribution information;

[0083] The coordinate inversion module is used to invert the coordinate values ​​of the target into the longitude and latitude coordinates of the target;

[0084] The coordinate value selection module is used to calculate the distance between the coordinate value of the target and each of the line equations, and to display the coordinate value of the target.

[0085] This invention provides a passive localization method and system for radar radiation source targets. It processes direction-finding line data in batches, dividing each batch of valid direction-finding line data into multiple batches of straight line equations. Based on the intersection points of these equations, multiple grid matrices are created, thereby providing localization results for one or more targets. The results from each batch are then summarized to finally provide the localization results (latitude and longitude coordinates) for one or more targets. Batch processing of direction-finding line data improves data processing capabilities, enabling near real-time localization results. Simultaneously with displaying the localization results, several corresponding direction-finding lines are selectively displayed, providing visualization of the results. This invention uses a density-based localization method, which is insensitive to outliers, has a wider applicability, and higher localization efficiency.

[0086] It will be apparent to those skilled in the art that the embodiments of the present invention are not limited to the details of the exemplary embodiments described above, and that the embodiments of the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the embodiments of the present invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the embodiments of the present invention is defined by the appended claims rather than the foregoing description. Therefore, all variations falling within the meaning and scope of equivalents of the claims are intended to be encompassed within the embodiments of the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims. Furthermore, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units, modules, or devices recited in the system, apparatus, or terminal claims may also be implemented by the same unit, module, or device through software or hardware.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention and are not intended to limit them. Although the embodiments of the present invention have been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the embodiments of the present invention should not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A passive localization method for radar radiation source targets, characterized in that, Includes the following steps: Step 1: Acquire data from multiple direction finding lines and extract the longitude, latitude, and direction of arrival angle vector of the direction finding lines; Step 2: Clean the data of the direction finding lines to remove invalid direction finding line data and obtain valid direction finding line data; determine whether the valid direction finding line data meets the positioning conditions. If yes, proceed to step 3; otherwise, terminate. Step 3: Using the center position of the reconnaissance aircraft's flight path as the origin, project the longitude and latitude of the flight path corresponding to the effective direction finding data onto the Cartesian coordinate system to obtain multiple vectors; Step 4: Transform the multiple vectors into multiple linear equations in the Cartesian coordinate system; Step 5: Divide the multiple linear equations into several batches and calculate the intersection points of all linear equations in all batches, including: extracting a batch of linear equations, calculating the intersection points of every two linear equations, and storing the x-coordinate and y-coordinate of the intersection points into an intersection point set. Step 6: Calculate the coordinates of the target based on the set of intersection points; Step 7: Calculate the distance between the coordinates of the target and the equations of each line, and sort the distances; Step 6 includes: Step 61: Select the range involved by the intersection point in the plane of the Cartesian coordinate system, and divide the range into several grid matrices evenly according to a threshold. Each grid matrix includes multiple grids, and each grid includes multiple sets of intersection points. Statistically analyze the density distribution information of the intersection point sets within the grid matrix. Step 62: Identify the grid with the highest density based on the density distribution information; If there is only one grid with the highest density, then the center coordinates of that grid are used as the coordinates of the target, and the value of those coordinates is returned. If there are multiple grids with the highest density, a target minimum distinguishing distance is pre-specified, and then the distance between every two grids with the highest density is calculated and compared with the target minimum distinguishing distance. When the distance is greater than the minimum distinguishing distance of the target, the center coordinates of the two grids with the highest density are used as the coordinates of the target, and the value of the coordinates is returned; When the distance is less than the minimum distinguishing distance of the target, the center coordinate of any grid with the highest density is taken as the coordinate of the target, and the value of that coordinate is returned; The coordinates are the coordinates of the target.

2. The passive localization method for radar radiation source targets according to claim 1, characterized in that, Also includes: Step 8: Summarize the coordinates of the target and the distance, and translate the coordinates of the target back into the latitude and longitude coordinates of the target; Step 9: Display the latitude and longitude coordinates of a certain number of the targets.

3. The passive localization method for radar radiation source targets according to claim 1, characterized in that, The removal of invalid direction finding line data includes: determining the number of direction finding lines; when the number of direction finding lines is less than 2, the direction finding lines are invalid direction finding line data, and removing the invalid direction finding line data.

4. The passive localization method for radar radiation source targets according to claim 3, characterized in that, The removal of invalid direction finding line data further includes: determining whether the longitude or latitude of the direction finding line deviates from the center position of the reconnaissance aircraft track by more than 2 degrees; if so, the direction finding line is invalid direction finding line data and the invalid direction finding line data is removed.

5. The passive localization method for radar radiation source targets according to claim 1, characterized in that, In step 3, the longitude and latitude of the track corresponding to the effective direction finding line data are projected onto the Cartesian coordinate system. The projection method is used to store the projection center and store the longitude and latitude coordinates projected onto the Cartesian coordinate system into a linked list.

6. The passive localization method for radar radiation source targets according to claim 1, characterized in that, Step 5 further includes: using the intersection calculation module to calculate the intersection point of each of the two line equations, and storing the coordinates of the intersection point in a linked list.

7. The passive localization method for radar radiation source targets according to claim 1, characterized in that, Step 61 further includes: determining whether there are fewer than 3 intersection points in the intersection point set; if so, defining the range of all intersection points as the grid matrix; if not, dividing the Cartesian coordinate system plane into a 600*600 grid matrix with the midpoint of the reconnaissance aircraft track as the origin.

8. A passive positioning system for radar radiation source targets, characterized in that, The passive positioning system includes: The module includes: acquisition module, data cleaning module, projection module, distance calculation module, batch processing module for linear equations, intersection calculation module, intersection density distribution statistics module, positioning module, coordinate inversion module, and coordinate value selection module. The acquisition module is used to acquire data of the direction finding line; The data cleaning module is used to remove invalid direction finding line data; The projection module projects the longitude and latitude of the track corresponding to the effective direction finding data onto the Cartesian coordinate system; The distance calculation module is used to calculate the distance between points and the distance between points and lines in the Cartesian coordinate system. The linear equation batch processing module is used to process the linear equations in batches. The intersection point calculation module is used to calculate the intersection points of the line equations; The intersection density distribution statistics module calculates the density distribution information of the intersection set within the grid matrix. The positioning module is used to find the grid with the highest density based on the density distribution information; The coordinate inversion module is used to invert the coordinate values ​​of the target into the longitude and latitude coordinates of the target; The coordinate value selection module is used to calculate the distance between the coordinate value of the target and each of the line equations, and to display the coordinate value of the target.

Images