Range-doppler two-dimensional plot condensation method based on or operation

Abstract

The present application relates to a kind of distance-doppler two-dimensional plot condensation methods based on or gate operation, for the accurate condensation of a large number of target plots when modern radar information processing.This application can realize the accurate condensation of a large number of target plots and achieve two purposes:1) avoid target splitting and expansion phenomenon, 2) reduce the amount of operation while improving the calculation accuracy of target position.The present application sets a certain size of distance-doppler wave gate, and uses or operation to connect one or more regions where the plots belonging to the same target are located into a region, i.e.the number of target condensation can be obtained, and then the centroid of the target plot of each region is calculated, and the specific position of the target can be obtained, which includes distance and doppler information.

Description

Technical Field

[0001] The present invention belongs to the field of radar technology and relates to a range-Doppler two-dimensional point trace aggregation method based on OR gate operation. The method is used to accurately aggregate a large number of target point traces during modern radar information processing, thereby avoiding target splitting and expansion, and improving the calculation accuracy of the target position while reducing the amount of calculation. Background Art

[0002] With the rapid development of computer and microelectronics technologies in recent years, the performance of modern radars has greatly improved. This has led to a significant increase in the number of target traces required for processing. This not only leads to target fragmentation and expansion, causing a single target to appear as multiple targets on the terminal, but also places a heavy computational burden on the computer. Therefore, it is necessary to use target aggregation methods to aggregate traces belonging to the same target and calculate the target's specific location, reducing the amount of subsequent computation.

[0003] However, currently used point-track aggregation methods all have unavoidable flaws. When the points of the same target are scattered across multiple disconnected regions, the contour-tracking region growing method will aggregate each region into a single target. Furthermore, when points belonging to different targets intersect in the range or Doppler dimensions, the cross-coagulation method cannot distinguish them. Furthermore, the commonly used range-Doppler two-dimensional point-track aggregation method, because it always compares points with extreme points, can easily aggregate smaller points located at the edge into another target. Summary of the Invention

[0004] Technical problems to be solved

[0005] To avoid the target splitting and expansion that can occur when accurately converging a large number of target traces during radar information processing, while simultaneously reducing computational effort and improving target position calculation accuracy, the present invention provides a range-Doppler two-dimensional trace converging method based on OR gate operations. This method effectively avoids target splitting and expansion, reduces computational effort, and improves target position calculation accuracy, achieving precise converging of target traces.

[0006] Technical Solution

[0007] A range-Doppler two-dimensional point trace aggregation method based on OR gate operation is characterized by the following steps:

[0008] Step 1: Obtain the point information of the target range-Doppler two-dimensional image through CFAR operation;

[0009] Step 2: Set the gate size and mark the target area for each dot in turn;

[0010] Step 3: Use the OR gate to fuse the target areas of all traces to obtain multiple connected areas;

[0011] Step 4: Calculate the specific number of connected areas through a loop;

[0012] Step 5: If the number of points in a connected area is 1, the point and the corresponding connected area are discarded. The number of connected areas is the number of targets after target condensation.

[0013] Step 6: Calculate the centroid of the points inside each connected area to obtain the distance and Doppler value of the target.

[0014] Further technical solution of the present invention: Step 6 is as follows:

[0015] Assume that a target connected region contains N traces, and the corresponding trace amplitude is {A1,A2,...,A N}, the distance dimension coordinates are {R1,R2,...,R N}, the Doppler coordinates are {D1,D2,...,D N}, the centroid formula for calculating the target distance value is:

[0016]

[0017] The formula for calculating the centroid of the target Doppler value is:

[0018]

[0019] A computer system, characterized in that it includes: 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.

[0020] A computer-readable storage medium is characterized by storing computer-executable instructions, which are used to implement the above method when executed.

[0021] Beneficial effects

[0022] The present invention provides a range-Doppler two-dimensional point trace aggregation method based on OR gate operation. The method sets a certain wave gate and uses OR operation to connect one or more areas where traces belonging to the same target are located into one area. The number of targets after aggregation can be obtained. The center of mass of the target traces in each area is then calculated in turn to obtain the specific location of the target, including information such as distance and Doppler. This method can achieve accurate aggregation of a large number of target traces and achieve two goals: 1) avoid target splitting and expansion, and 2) improve the calculation accuracy of the target position while reducing the amount of calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying 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 parts throughout the drawings.

[0024] Figure 1 MTD images processed by CFAR;

[0025] Figure 2 The flow chart of target range matrix partitioning of the trace group in the upper left corner of MTD;

[0026] Figure 3 The target point group in the upper left corner of MTD or the target area fused after gate operation;

[0027] Figure 4 MTD overall target trace or target area fused after gate operation;

[0028] Figure 5 MTD overall target trace or target area fused after gate operation (not marked);

[0029] Figure 6 Schematic diagram of the integrated targets and their numbers in the MTD overall target area;

[0030] Figure 7 The final target area after the MTD overall target area is condensed. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only intended to illustrate 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 may be combined with each other as long as they do not conflict with each other.

[0032] The technical solution of the present invention is as follows: first, the size of a range-Doppler two-dimensional wave gate is set, and the value within each point trace wave gate can be considered as the area where the target is located. The target areas of all point traces are merged using an OR gate, and one or more areas where the traces belonging to the same target are located are connected into one area. Disconnected areas belong to different targets. The number of connected areas is the number of targets after condensation. Then, the centroid of the target point trace in each area is calculated in turn to obtain information such as the distance and Doppler of the target. In this way, the range-Doppler two-dimensional point trace condensation based on the OR gate operation is realized.

[0033] The present invention implements the steps as follows:

[0034] (1) Obtaining the point trace information of the target range-Doppler two-dimensional image through CFAR operation;

[0035] (2) Set the gate size and mark the target area of ​​each point in turn;

[0036] (3) Use OR gate to fuse the target areas of all traces to obtain multiple connected areas;

[0037] (4) Calculate the specific number of connected areas through loops;

[0038] (5) If the number of traces contained in a connected area is 1, the trace and the corresponding connected area are discarded together. The number of connected areas is the number of targets after target condensation.

[0039] (6) Calculate the centroid of the points inside each connected area to obtain the distance and Doppler value of the target.

[0040] In order to enable those skilled in the art to better understand the present invention, the present invention is described in detail below with reference to specific embodiments.

[0041] Assume that the range-Doppler two-dimensional matrix containing the target has been obtained, after constant false alarm detection and point agglomeration processing; assume that the MTD image processed by CFAR has been obtained, such as Figure 1 As shown, the size is 20*25, the horizontal axis is the distance dimension, the vertical axis is the Doppler dimension, and the target point traces exceeding the threshold retain the original amplitude. Figure 1 The dark color is used to mark the area, and the value that does not exceed the threshold is set to 0, indicating that there is no target point trace here. The specific implementation steps of the method proposed in the present invention are as follows:

[0042] Step 1: Set the gate size m*n and mark the target area for each point in turn.

[0043] against Figure 1 The MTD image shown in the figure sets the gate to 3*3, indicating that the area around the dot is considered to be the target area. Figure 1 Take the upper left corner target point group as an example, Figure 2 As shown in the figure, there are 8 target traces in total. A 3*3 wave gate is placed at the center of a trace in the dark area. The center of the wave gate coincides with the trace. At this time, the inside of the wave gate, that is, the light-colored area, is considered to be the target range, and its value is set to 1. The outside of the wave gate is not considered to be the target range, and its value is set to 0. In this way, a target range matrix can be obtained.

[0044] Depend on Figure 2 As shown, 8 target point traces can obtain 8 target range matrices.

[0045] Step 2: Use the OR gate to fuse the target areas of all traces to obtain multiple connected areas.

[0046] Perform an OR operation on the multiple target range matrices obtained in step 1. That is, when a value is 1 at the same position of all target matrices, its value is set to 1, indicating that this is the target range. When all matrices at this position are 0, the fused value is set to 0. Figure 2 The target area in the upper left corner of the MTD image can be obtained by OR gate operation of the 8 target range matrices. Figure 3 shown.

[0047] The target area obtained by the target range matrix calculated by the target point trace of the entire MTD image through the OR gate operation is as follows: Figure 4 shown.

[0048] Step 3: Calculate the specific number of connected areas through loops.

[0049] observe Figure 4 For the convenience of observation, the connected areas are marked with colors. The naked eye can clearly observe that there are 4 connected areas in the MTD image, but the MTD connected areas in computer processing are as follows: Figure 5 As shown in the figure, neither the computer nor the naked eye can directly see the number of connected areas of the target, so it is necessary to integrate adjacent values ​​into the same target through a loop and number the targets in the order of 1, 2, 3, 4...

[0050] By looping Figure 5 The MTD images are integrated and numbered. For easy observation, the integrated target areas are still marked with colors. The results are as follows: Figure 6 As shown, there are 4 suspected targets at this time.

[0051] (4) If the number of points contained in the connected area is 1, the point and the corresponding connected area are discarded together. At this time, the number of connected areas is the number of targets after condensation.

[0052] A single point in the MTD image is usually a clutter point and needs to be removed. Figure 6 The target connected area and its number are Figure 1 Comparing the target traces with the target traces, we can see that there is only one target trace in the target connected area numbered 4. This target and the corresponding connected area are discarded, that is, assigned a value of 0. At this time, the number of connected areas is reduced to 3, that is, the number of targets in the MTD image after target aggregation is 3. The target area after discarding the clutter traces is as follows Figure 7 As shown, different labeled colors represent different target connected areas.

[0053] (5) By calculating the centroid of the points inside each connected area from the two dimensions of distance and Doppler, the distance and Doppler value of each target can be obtained.

[0054] Assume that a target connected region contains N traces, and the corresponding trace amplitude is {A1,A2,...,A N}, the distance dimension coordinates are {R1,R2,...,R N}, the Doppler coordinates are {D1,D2,...,D N}, the centroid formula for calculating the target distance value is:

[0055]

[0056] The formula for calculating the centroid of the target Doppler value is:

[0057]

[0058] According to formula 1 and formula 2, we can calculate Figure 7 The distance and Doppler values ​​of the three targets shown in Figure 1 are as follows. So far, the distance-Doppler two-dimensional point condensation method based on OR gate operation has been used to achieve the Figure 1 Target cohesion of MTD images.

[0059] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present invention, and these modifications or replacements should all be included in the scope of protection of the present invention.

Claims

1. A range-Doppler two-dimensional point trace aggregation method based on OR gate operation, characterized in that Here are the steps: Step 1: Obtain the point information of the target range-Doppler two-dimensional image through CFAR operation; Step 2: Set the gate size and mark the target area for each dot in turn; Step 3: Use the OR gate to fuse the target areas of all traces to obtain multiple connected areas; Step 4: Calculate the specific number of connected areas through a loop; Step 5: If the number of points in a connected area is 1, the point and the corresponding connected area are discarded. The number of connected areas is the number of targets after target condensation. Step 6: Calculate the centroid of the points inside each connected area to obtain the distance and Doppler value of the target.

2. The range-Doppler two-dimensional point trace aggregation method based on OR gate operation according to claim 1, characterized in that: Step 6 is as follows: Assume that a target connected region contains N traces, and the corresponding trace amplitude is {A1,A2,...,A N }, the distance dimension coordinates are {R1,R2,...,R N }, the Doppler coordinates are {D1,D2,...,D N }, the centroid formula for calculating the target distance value is: The formula for calculating the centroid of the target Doppler value is:

3. 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 are enabled to implement the method of claim 1.

4. 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 of claim 1.

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