A method for multi-target positioning of the same frequency applicable to an airborne platform

Abstract

This invention relates to a method for localizing multiple targets at the same frequency on airborne platforms, belonging to the field of passive localization and tracking technology. The invention first estimates the number of targets at the same frequency. Then, considering the motion characteristics of the airborne platform, it selects multiple spatially discrete locations and constructs localization equations for the multiple targets at the same frequency. A histogram statistical processing algorithm is used to eliminate false targets, and the filtered target positions are further filtered to improve the accuracy of target position estimation. This invention can adaptively estimate the number of targets at the same frequency and automatically eliminate false targets. It features strong real-time performance and ease of engineering application, making it particularly suitable for passive localization and tracking of targets with unknown radiation sources on airborne platforms.

Description

Technical Field

[0001] This invention relates to a real-time positioning and processing method for multiple targets at the same frequency on an airborne platform, which is particularly suitable for ground target positioning and tracking in the field of airborne spectrum monitoring, and realizes the estimation of latitude and longitude parameters of multiple ground devices at the same frequency. Background Technology

[0002] Passive positioning technology based on airborne platforms is one of the fastest-growing passive positioning technologies in recent years. It possesses unique advantages: high altitude, long operating range, and large coverage area; strong maneuverability, easy formation flying, and rapid transfer from one area to another; and, most importantly, the ability to locate radiation sources using only one aircraft (one system), avoiding complex time synchronization and data fusion between multiple aircraft. Currently, airborne spectrum monitoring equipment cannot distinguish between multiple targets operating on the same frequency (e.g., radio stations, walkie-talkies) and other communication terminals, resulting in numerous false targets in the positioning results. Therefore, this paper proposes a real-time multi-target positioning processing method based on an airborne platform, which can effectively solve the problem of single-station multi-target positioning applications. Summary of the Invention

[0003] This invention addresses the high-precision positioning of multiple targets at the same frequency on airborne platforms. It proposes a real-time positioning processing method suitable for airborne platforms. This method involves performing pairwise intersection positioning calculations on multiple directions at the same location and frequency, and then performing two-dimensional clustering classification on the positioning results to eliminate false targets, ultimately estimating the number and location of the targets. This invention offers advantages such as low computational complexity, high accuracy, strong real-time performance, and ease of engineering implementation, making it particularly suitable for positioning multiple targets at the same frequency on a single airborne platform.

[0004] The technical problem to be solved by this invention is achieved by the following technical solution:

[0005] A method for processing multiple targets at the same frequency on an airborne platform includes the following steps:

[0006] (1) Receive direction finding data at a specified frequency, store the direction finding data in a set storage space, and set the storage time length of the direction finding data to be [value missing]. Seconds, number of direction finding data points And record the current location of the airborne platform ( , );in, and All are natural numbers greater than 1;

[0007] (2) To The direction finding data is clustered and separated to obtain the number of targets at the current time and the target direction finding result for each target. ,in Representing a moment, Representing the One goal;

[0008] (3) Utilize target direction finding results at multiple different times Combined with the location of the airborne platform corresponding to the direction finding time ( , The target position is obtained by performing dual-station direction finding and rendezvous positioning. ;

[0009] (4) For multiple target locations Perform false target removal to obtain the true target location. ;

[0010] (5) Target location Using a distance classification method, the number of targets and their corresponding location information are extracted, resulting in high-precision target location information. The number of targets is then reported. and target position parameters .

[0011] Furthermore, the specific method for step (2) is as follows:

[0012] (201) will Each direction finding data point is statistically analyzed within the range of 0° to 360°, with a statistical step angle interval of [missing value]. ,in Less accurate than the direction finding accuracy of the direction finding system;

[0013] (202) Smooth the statistical direction finding data;

[0014] (203) Perform peak search on the smoothed direction finding statistical curve and normalize adjacent peaks;

[0015] (204) Extract the number of targets and the target direction finding results. ,in Representing a moment, Representing the One goal.

[0016] Furthermore, the specific method for step (3) is as follows:

[0017] (301) Select a direction finding interval of not less than The two sets of target orientation measurement results are used to perform dual-station orientation measurement intersection positioning to obtain the target location information; among them... Set value;

[0018] (302) Repeat step (301) iterate through multiple sets of direction finding data to obtain multiple sets of target location information. , It refers to the number of positioning points.

[0019] Furthermore, the specific method for step (4) is as follows:

[0020] (401) Extract longitude information from multiple target locations Latitude and longitude information Longitude information Latitude and longitude information Statistical analysis was performed in the range of -180° to 180°, with the step intervals being statistically analyzed. ,in Less than the system positioning accuracy;

[0021] (402) Smooth the statistical longitude and latitude data respectively, and perform peak search on the smoothed longitude curve and latitude curve respectively to determine the number of longitude peaks, peak start position and peak end position, as well as the number of latitude peaks, peak start position and peak end position;

[0022] (403) Filter out target location information between the peak start position and the peak end position. ,in Not greater than Natural numbers;

[0023] (404) Filter out the target location information Repeat steps (401) to (403) to obtain the final target location information. ,in Not greater than Natural numbers.

[0024] Furthermore, the specific method for step (5) is as follows:

[0025] (501) Using the latitude and longitude information of the first target location point For reference, the distances from the target location to the remaining target locations are calculated, resulting in a distance information array. , ;

[0026] (502) Find the distance information array maximum value Distance information data in the range of 0~ Perform interval statistics and calculate the step interval. ,in Less than the system positioning accuracy;

[0027] (503) Perform a peak search on the distance statistics curve to determine the number of peaks in the distance statistics curve. Peak start position and the end position of the peak Where p is at 1~ ;

[0028] (504) Based on the starting position of the peak of the distance statistical curve and the end position of the peak The target location information corresponding to the p-th target peak is selected, and the target location information is averaged to obtain the latitude and longitude information of the p-th target. .

[0029] The present invention has the following advantages:

[0030] 1) This invention can automatically estimate the number of targets with the same frequency.

[0031] 2) This invention can automatically remove false target locations with the same frequency and obtain the latitude and longitude information of the real target location.

[0032] 3) This invention requires little computation and is easy to implement in engineering. Attached Figure Description

[0033] Figure 1 This is a flowchart of an embodiment of the present invention.

[0034] Figure 2 This is a flowchart of the direction-finding clustering process according to an embodiment of the present invention.

[0035] Figure 3 This is a diagram showing the results of multiple intersection and positioning in an embodiment of the present invention. Detailed Implementation

[0036] Reference Figures 1-3 The present invention will be further described below.

[0037] A method for real-time localization of multiple targets at the same frequency on an airborne platform, such as Figure 1 As shown, it includes the following steps:

[0038] (1) Receive direction finding data at a specified frequency, store the direction finding data in a set storage space, and set the storage time length of the direction finding data to be [value missing]. Seconds, number of direction finding data points Among them, duration and number It is a natural number greater than 1, and records the current platform position ( , ), Usually 100 are selected, duration 10 seconds is usually chosen.

[0039] (2) To The direction finding data is clustered and separated to obtain the number of targets at the current time and the target direction finding result for each target. ,in Representing a moment, Representing the One goal.

[0040] The specific method in step (2) is as follows:

[0041] (201) will Each direction finding data point is statistically analyzed within the 0°–360° range, and the step angle interval is statistically calculated. ,in The requirement is less than the direction finding accuracy of the direction finding system, and the angle interval is... A 1° step is typically chosen, and the statistical processing flowchart is as follows: Figure 2 As shown;

[0042] (202) Smooth the statistical direction finding data;

[0043] (203) Perform peak search on the smoothed direction finding statistical curve and normalize the adjacent peaks;

[0044] (204) Extract the target number and target direction finding information .

[0045] (3) Utilize target direction finding results at multiple different times Combined with the position of the motion platform corresponding to the direction finding time ( , The target position is obtained by performing dual-station direction finding and rendezvous positioning. information.

[0046] The specific method for step (3) is as follows:

[0047] (301) Select a direction finding interval of not less than Using the two sets of target direction finding results, dual-station direction finding rendezvous positioning is performed to obtain target position information and direction finding interval. The angle requirement is greater than 10°. The rendezvous and rendezvous positioning formula based on spherical orientation finding is shown below, where the position of positioning station A1 is... Location A2 of Positioning Station 2 ;

[0048] First, calculate the distance between the two direction finding stations. , ;

[0049] in, Finally, the target's latitude and longitude were calculated. information.

[0050]

[0051] in The direction finding results for positioning station A1 are as follows. The direction finding results are for location station A2. The angle of A2 as seen from positioning station A1, where The angle from station A2 to A1. For target longitude information, For target latitude information, The arc length of the sphere between the two points;

[0052] (302) Repeat step (301) iterate through multiple sets of direction finding data to obtain multiple sets of target location information. , This refers to the number of positioning points; the positioning result is as follows: Figure 3 As shown.

[0053] (4) For multiple target locations The data is processed to remove false targets, thus obtaining the true target locations. .

[0054] The specific method in step (4) is as follows:

[0055] (401) Extract longitude information from multiple target locations Latitude and longitude information Longitude information Latitude and longitude information Statistical analysis was performed in the range of -180° to 180°, with the step intervals being statistically analyzed. ,in Less than the system positioning accuracy;

[0056] (402) Smooth the statistical longitude and latitude data respectively, and perform peak search on the smoothed longitude curve and latitude curve respectively to determine the number of longitude peaks, peak start position and peak end position, as well as the number of latitude peaks, peak start position and peak end position;

[0057] (403) Filter out target location information between the peak start position and the peak end position. ,in Not greater than Natural numbers;

[0058] (404) Filter out the target location information Repeat steps (401) to (403) to obtain the final target location information. ,in Not greater than Natural numbers.

[0059] (5) The separated target location Using a distance classification method, the number of targets and their corresponding location information are extracted, resulting in high-precision target location information. The number of targets is then reported. and position parameters .

[0060] The specific method in step (5) is as follows:

[0061] (501) Using the latitude and longitude information of the first target location point For reference, the distances from the target location to the remaining target locations are calculated, resulting in a distance information array. ;

[0062] .

[0063] (502) Find the distance information array maximum value Distance information data in the range of 0~ Perform interval statistics and calculate the step interval. ,in The requirement is less than the system positioning accuracy;

[0064] (503) Perform a peak search on the distance statistics curve to determine the number of peaks in the distance statistics curve. Peak start position and the end position of the peak Where p is at 1~ ;

[0065] (504) Based on the starting position of the peak of the distance statistical curve and the end position of the peak The target location information corresponding to the p-th target peak is selected, and the target location information is averaged to obtain the latitude and longitude information of the p-th target. .

Claims

1. A method for processing multi-target localization at the same frequency on an airborne platform, characterized in that, Includes the following steps: (1) Receive direction finding data at a specified frequency, store the direction finding data in a set storage space, and set the storage time length of the direction finding data to be [value missing]. Seconds, number of direction finding data points And record the current location of the airborne platform ( , );in, and All are natural numbers greater than 1; (2) To The direction finding data is clustered and separated to obtain the number of targets at the current time and the target direction finding result for each target. ,in Representing a moment, Representing the One goal; (3) Utilize target direction finding results at multiple different times Combined with the location of the airborne platform corresponding to the direction finding time ( , The target position is obtained by performing dual-station direction finding and rendezvous positioning. ; (4) For multiple target locations Perform false target removal to obtain the true target location. ; (5) Target location Using a distance classification method, the number of targets and their corresponding location information are extracted, resulting in high-precision target location information. The number of targets is then reported. and target position parameters .

2. The method for processing multiple targets at the same frequency on an airborne platform according to claim 1, characterized in that, The specific method for step (2) is as follows: (201) will Each direction finding data point is statistically analyzed within the range of 0° to 360°, with a statistical step angle interval of [missing value]. ,in Less accurate than the direction finding accuracy of the direction finding system; (202) Smooth the statistical direction finding data; (203) Perform peak search on the smoothed direction finding statistical curve and normalize adjacent peaks; (204) Extract the number of targets and the target direction finding results. ,in Representing a moment, Representing the One goal.

3. The method for simultaneous multi-target localization processing on an airborne platform according to claim 1, characterized in that, The specific method for step (3) is as follows: (301) Select a direction finding interval of not less than The two sets of target orientation measurement results are used to perform dual-station orientation measurement intersection positioning to obtain the target location information; among them... Set value; (302) Repeat step (301) iterate through multiple sets of direction finding data to obtain multiple sets of target location information. , It refers to the number of positioning points.

4. The method for processing multiple targets at the same frequency on an airborne platform according to claim 1, characterized in that, The specific method for step (4) is as follows: (401) Extract longitude information from multiple target locations Latitude and longitude information Longitude information Latitude and longitude information Statistical analysis was performed in the range of -180° to 180°, with the step intervals being statistically analyzed. ,in Less than the system positioning accuracy; (402) Smooth the statistical longitude and latitude data respectively, and perform peak search on the smoothed longitude curve and latitude curve respectively to determine the number of longitude peaks, peak start position and peak end position, as well as the number of latitude peaks, peak start position and peak end position; (403) Filter out target location information between the peak start position and the peak end position. ,in Not greater than Natural numbers; (404) Filter out the target location information Repeat steps (401) to (403) to obtain the final target location information. ,in Not greater than Natural numbers.

5. The method for processing multiple targets at the same frequency on an airborne platform according to claim 1, characterized in that, The specific method for step (5) is as follows: (501) Using the latitude and longitude information of the first target location point For reference, the distances from the target location to the remaining target locations are calculated, resulting in a distance information array. , ; (502) Find the distance information array maximum value Distance information data in the range of 0~ Perform interval statistics and calculate the step interval. ,in Less than the system positioning accuracy; (503) Perform a peak search on the distance statistics curve to determine the number of peaks in the distance statistics curve. Peak start position and the end position of the peak Where p is at 1~ ; (504) Based on the starting position of the peak of the distance statistical curve and the end position of the peak The target location information corresponding to the p-th target peak is selected, and the target location information is averaged to obtain the latitude and longitude information of the p-th target. .

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