A method for temporary track establishment of an over-the-horizon search radar

Abstract

The application discloses a kind of temporary track establishment methods of air search radar, it is related to radar information processing technical field.The method includes: calculating coarse granularity and minimum concern distance under sector angle of fine granularity division;Recording the double sector index of original track;During the radar scanning process, according to the relationship between original track distance and minimum concern distance, dynamically extract the set of point track to be associated, wherein the short-range point track is associated with all candidate point tracks, and the long-range point track is only associated with the point track of adjacent sector with fine granularity index;Calculate the absolute speed between point tracks and judge whether it meets the speed gate, and if it meets, establish temporary track.The application can reduce the number of long-range point track association, save the cost of calculation, and improve the processing efficiency.

Description

Technical Field

[0001] This invention relates to the field of information processing technology for air search radar, and specifically to a method for initiating temporary tracks during the information processing of air search radar. Background Technology

[0002] In the information processing flow of a 360° circular scan air search radar, a temporary track is established after the original tracks of two adjacent antenna scan frames are successfully correlated. The general steps for starting a temporary track are as follows:

[0003] Step 1: Divide the 360° circle evenly into N sectors;

[0004] Step 2: When the antenna scans the k-th sector, acquire the original data points within this sector.

[0005]

[0006] in, This represents the number of original dots in the k-th sector of the current frame.

[0007] Step 3: Obtain the points to be associated from the previous frame, including the original points of sectors k-1, k, and k+1, respectively.

[0008]

[0009]

[0010]

[0011] in , and These represent the number of dots in the (k-1), k, and k+1th sectors of the previous frame, respectively.

[0012] Step 4: Traverse the original points in the k-th sector of this frame, and convert the distance, azimuth, and elevation information of the points into Cartesian coordinate position information centered on the radar. ,in .

[0013] Step 5: Traverse the original points to be associated in the previous frame, and convert the distance, azimuth, and elevation information of the points into Cartesian coordinate position information centered on the radar. ,in .

[0014] Step 6: Calculate the Euclidean distance between the original point positions obtained in Steps 4 and 5.

[0015]

[0016] Among them, elements The calculation formula is: .

[0017] Step 7: Calculate the absolute velocity magnitude of the dots between two adjacent frames.

[0018]

[0019] Among them, elements The calculation formula is:

[0020]

[0021] in, To detect the original trace At that moment, To detect the original trace At that moment.

[0022] Step 8, Traverse ,judge Is it in radar-associated velocity gate? The specific conditions are as follows:

[0023]

[0024] If satisfied, then construct a record of the original points. and A temporary track must be established; otherwise, no temporary track will be established.

[0025] The above processing method divides the search airspace into N fixed sectors. In order to ensure the success rate of establishing real flight paths, the sector angles are usually relatively large, which leads to an increase in the number of points that need to be associated in a single run, thus increasing the computational load. Summary of the Invention

[0026] In view of this, the present invention provides a method for establishing temporary tracks for air search radar. This method considers the relative relationship between the radial distance and tangential motion distance of different targets under the same sector angle. It adopts coarse-grained sector division for the short-range range and fine-grained sector division for the long-range range, which can greatly reduce the number of long-range track associations and save computational costs.

[0027] A method for establishing a temporary track for an air search radar, comprising the following steps:

[0028] Step 1: Calculate the angle of the coarse-grained sector.

[0029] Step 2: Calculate the fine-grained sector angle;

[0030] Step 3: Calculate the minimum radar range of interest under fine-grained segmentation.

[0031] Step 4: Record the original point sector index;

[0032] Step 5: Determine if the radar scan has been performed at too coarse a granular level. If all sectors have been scanned, proceed to step six; otherwise, proceed to step four.

[0033] Step 6: Obtain the original point traces and all points to be associated;

[0034] Step 7: Traverse the original set of points;

[0035] Step 8: Determine if the traversal is complete. If it is, go to step 4; otherwise, go to step 9.

[0036] Step 9: Extract the set of points to be associated;

[0037] Step 10: Traverse the extracted set of points to be associated;

[0038] Step 11: Determine if the traversal is complete. If it is, go to step 7; otherwise, go to step 12.

[0039] Step 12: Calculate the absolute velocity magnitudes of the original point trace and the point trace to be associated. ;

[0040] Step Thirteen, Judgment Does it meet the requirements? If the condition is met, proceed to step fourteen; otherwise, proceed to step ten.

[0041] Step 14: Establish temporary tracks for the original points and the points to be associated.

[0042] Furthermore, the coarse-grained division divides the 360° circumference into N uniform sectors, while the fine-grained division divides the 360° circumference into 2N uniform sectors.

[0043] Assuming the minimum range of interest for the air search radar is The maximum distance is The maximum speed of the trackable target is The time taken for a radar scan to complete one cycle is calculated according to the chord length formula:

[0044]

[0045] At the radar's minimum range of interest, the maximum angle the target can move within a full radar scan is:

[0046]

[0047] So, the sector angle of coarse-grained partitioning fine-grained sector angle In the case of fine-grained sector division, the minimum range that the radar needs to focus on is:

[0048] .

[0049] Furthermore, in step one, the angle of the coarse-grained sector is calculated as follows: Optimal The calculation formula is

[0050]

[0051] The unit is °. Since the number of coarse-grained sectors must be an integer, the number of sectors is:

[0052]

[0053] So, for The corrected calculation formula is as follows:

[0054] .

[0055] Furthermore, in step three, the minimum radar range of interest... The calculation formula is as follows;

[0056] .

[0057] Furthermore, in step four, the sector indices of the original traces in both the coarse-grained and fine-grained partitions are recorded, wherein the coarse-grained index value is... Fine-grained index value .

[0058] Furthermore, the original dots in step six are from the first dot of this frame. Each sector, denoted as All the points to be associated come from the original points of sectors k-1, k, and k+1 in the previous frame's coarse-grained division, denoted as .

[0059] Furthermore, step nine involves extracting the set of traces to be associated and determining the original traces. distance Minimum range of interest for radar under fine-grained classification The relationship; if Then the unassociated traces of this original trace come from the set of all unassociated traces. Otherwise, based on the original dot pattern Extracting from the finely divided sector index g. Points with sector indices of g-1, g, or g+1 under fine-grained partitioning are considered as points to be associated. For ease of representation, the final extracted points to be associated are uniformly represented as follows: .

[0060] Furthermore, the absolute velocity magnitude in step twelve The specific calculation formula is as follows:

[0061]

[0062] The unit is meters per second.

[0063] Beneficial effects:

[0064] This invention optimizes computational resource allocation by introducing a two-tiered sector partitioning mechanism (coarse-grained and fine-grained) and dynamically adjusting the selection range of traces to be associated based on the target's radial distance. Specifically, this method first calculates the coarse-grained and fine-grained sector angles and the minimum range of interest in the fine-grained mode based on radar physical parameters. Then, during scanning, it synchronously records the dual sector indices of the traces. Based on this, when processing the original traces, a differentiated strategy is executed according to the relative relationship between their distance and the minimum range of interest: for near-range traces, all traces to be associated are retained to ensure robustness in navigation establishment; for long-range traces, the fine-grained sector index is used to precisely narrow their association range to three adjacent fine-grained sectors. This process allows long-range traces to directly lock onto high-probability matching areas without traversing all neighboring traces in the previous frame, thus significantly reducing the number of calculations for absolute velocity. This effectively solves the problem of excessive computational load and low processing efficiency in long-range association caused by traditional fixed sector partitioning. This method, while ensuring the reliability of short-range target detection, significantly reduces the system's computational load, improves the real-time response capability and overall operational stability of the radar information processing subsystem, and forms a complete logical closed loop from parameter calculation and hierarchical screening to speed criterion-based navigation. Attached Figure Description

[0065] Figure 1 This is a flowchart of the temporary track establishment method of the present invention;

[0066] Figure 2 Diagram illustrating the principle of sector partitioning;

[0067] Figure 3 This is a schematic diagram of the distribution of clutter points 1 to 9 in the sector in the example embodiment. Detailed Implementation

[0068] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0069] This invention employs two sector division methods: coarse-grained and fine-grained. The coarse-grained method divides the 360° circumference into N uniform sectors, while the fine-grained method divides the 360° circumference into 2N uniform sectors.

[0070] Assuming the minimum range of interest for the air search radar is (Unit: meters), maximum distance is (Unit: meters), the maximum speed of the trackable target is (Unit: meters per second), the time taken for a radar scan to complete one cycle is (Unit: seconds). According to the chord length formula:

[0071]

[0072] At the radar's minimum range of interest, the maximum angle the target can move within a full radar scan is:

[0073]

[0074] So, the sector angle of coarse-grained partitioning fine-grained sector angle In the case of fine-grained sector division, the minimum range that the radar needs to focus on is...

[0075]

[0076] The division principle is as follows: Figure 2 As shown, A represents the radar center; sector AFG represents the k-th sector under coarse-grained division; sectors AFI and AIG represent sectors under fine-grained division; and sector rings CBDE represent the radar's region of interest within the k-th sector under coarse-grained division, where AC = AB = AD=AE= EDFG (Electronic Field-Oriented Group) – represents the radar's region of interest within a finely divided sector.

[0077] After the radar scans through the k-th sector under the coarse-grained division, the original point trace of this sector is obtained as follows:

[0078]

[0079] in, This represents the number of original dots in the k-th sector of the current frame.

[0080] At the same time, the original point traces of the (k-1), k, and k+1 sectors under the coarse-grained division of the previous frame are obtained as follows:

[0081]

[0082]

[0083]

[0084] in , and These represent the number of dots in the (k-1), k, and k+1th sectors of the previous frame, respectively.

[0085] Traverse the original points; if the distance between the points is within... If the distance between the points is within the range, then all points to be associated in the previous frame need to be considered for association; if the distance between the points is within the range... Within the specified range, if the sector index of a point under fine-grained partitioning is g, then only the points to be associated in sectors g-1, g, and g+1 need to be considered for association. Since the sector angle under fine-grained partitioning is only half that under coarse-grained partitioning, the amount of computation required for association of remote original points is reduced.

[0086] Assuming the minimum range of interest for the air search radar is (Unit: meters), maximum distance is (Unit: meters), the maximum speed of the trackable target is (Unit: meters per second), the time taken for a radar scan to complete one cycle is... (Unit: seconds). The implementation steps of the temporary track establishment method for the air search radar of the present invention are as follows: Figure 1 As shown:

[0087] Step 1: Calculate the angle of the coarse-grained sector division. Optimal The calculation formula is

[0088]

[0089] The unit is °. Since the number of coarse-grained sectors must be an integer, the number of sectors is:

[0090]

[0091] So, for The corrected calculation formula is as follows:

[0092]

[0093] Step 2, calculate the fine-grained sector angle. ;

[0094] Step 3: Calculate the minimum radar range of interest under fine-grained segmentation. The calculation formula is as follows;

[0095]

[0096] Step 4: Record the sector index of the original point trace. Record the sector indexes of the coarse-grained and fine-grained partitions where the original point trace is located. The coarse-grained index value is... Fine-grained index value ;

[0097] Step 5: Determine if the radar scans the first segment under coarse-grained division. If all sectors have been scanned, proceed to step 6; otherwise, proceed to step 4.

[0098] Step 6: Obtain the original point traces and all points to be associated, where the original point traces come from the first point trace of this frame. Each sector, denoted as All the points to be associated come from the original points of sectors k-1, k, and k+1 in the previous frame's coarse-grained division, denoted as ;

[0099] Step 7: Traverse the original set of points;

[0100] Step 8: Determine if the traversal is complete. If it is complete, go to step 4; otherwise, go to step 9.

[0101] Step 9: Extract the set of points to be associated and determine the original points. distance Minimum range of interest for radar under fine-grained classification If the relationship, Then the unassociated traces of this original trace come from the set of all unassociated traces. Otherwise, based on the original dot pattern Extracting from the finely divided sector index g. Points with sector indices of g-1, g, or g+1 under fine-grained partitioning are considered as points to be associated. For ease of representation, the final extracted points to be associated are uniformly represented as follows: .

[0102] Step 10: Traverse the extracted set of points to be associated;

[0103] Step 11: Determine if the traversal is complete. If it is complete, go to step 7; otherwise, go to step 12.

[0104] Step 12: Calculate the absolute velocity magnitudes of the original point trace and the point trace to be associated. The specific calculation formula is as follows:

[0105]

[0106] The unit is meters per second.

[0107] Step 13, Determine Does it meet the requirements? If the condition is met, proceed to step 14; otherwise, proceed to step 10.

[0108] Step 14, process the original dots with the trace to be associated Establish a temporary flight path.

[0109] Application Examples

[0110] Assuming the minimum range of interest for the air search radar is =100km, maximum distance is =300km, the minimum speed of the target that can be tracked is 50m / s, the maximum speed is 500m / s, and the radar takes 10s to scan one circle.

[0111] Step 1: Calculate the angle of the coarse-grained sector division. Optimal The calculation formula is

[0112]

[0113] The unit is °. Since the number of coarse-grained sectors must be an integer, the number of sectors is:

[0114]

[0115] So, for The corrected calculation formula is as follows.

[0116]

[0117] Step 2, calculate the fine-grained sector angle. ;

[0118] Step 3: Calculate the minimum radar range of interest under fine-grained segmentation. The calculation formula is as follows;

[0119]

[0120] Step 4: Record the sector index of the original point trace. Record the sector indexes of the coarse-grained and fine-grained partitions where the original point trace is located. The coarse-grained index value is... Fine-grained index value ;

[0121] Assume the target point to be associated is p1, with an azimuth of 29.8° and a distance of 250km; the original target point is p2, with an azimuth of 30.3° and a distance of 250km; additionally, there are clutter points 1–9. Clutter points 1–6 have azimuths of 26.64°, 28.08°, 29.52°, 30.96°, 32.4°, and 33.8°, respectively, and a distance of 220km; clutter points 7, 8, and 9 have azimuths of 28.08°, 29.52°, and 33.8°, respectively, and a distance of 150km. The specific distribution is shown in the attached figure. Figure 3 As shown, this example only illustrates the process of establishing a temporary track for a single target; for multiple targets, it is only necessary to iterate through them.

[0122] Step 5: Determine whether the radar has scanned the 11th sector under the coarse-grained division. If it has scanned the entire sector, proceed to step 6; otherwise, proceed to step 4.

[0123] Step 6: Obtain the original target point p2 and all points to be associated, where all points to be associated come from the original points of sectors 10, 11, and 12 under the coarse-grained division of the previous frame, denoted as p2. (Includes clutter traces 1~9 and target trace p1 to be associated);

[0124] Step 7, determine the distance to the original point p2. Minimum range of interest for radar under fine-grained classification The relationship. Because the distance of p2 is 250km greater than... Then extract Points with sector indices of 21, 22, and 23 that meet the requirements of fine-grained partitioning are selected as points to be associated. (Including clutter traces 3, 4, 5, 8 and target trace p1 to be associated).

[0125] Step 8: Traverse the extracted set of points to be associated;

[0126] Step 9: Calculate the absolute velocity magnitudes of the original point trace and the point trace to be associated. ,get (Clutter spot 3) (Clutter spot 4) (Clutter mark 5) (Clutter mark 8) (Target point trace);

[0127] Step 10, Determine Does it meet the requirements? Only get satisfy;

[0128] Step 14: Establish temporary tracks for p2 and p1.

[0129] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for establishing temporary tracks for an air search radar, characterized in that, The steps to implement this method are as follows: Step 1: Calculate the angle of the coarse-grained sector. Step 2: Calculate the fine-grained sector angle; Step 3: Calculate the minimum radar range of interest under fine-grained segmentation. Step 4: Record the original point sector index; Step 5: Determine if the radar scan has been performed at too coarse a granular level. If all sectors have been scanned, proceed to step six; otherwise, proceed to step four. Step 6: Obtain the original point traces and all points to be associated; Step 7: Traverse the original set of points; Step 8: Determine if the traversal is complete. If it is, go to step 4; otherwise, go to step 9. Step 9: Extract the set of points to be associated; Step 10: Traverse the extracted set of points to be associated; Step 11: Determine if the traversal is complete. If it is, go to step 7; otherwise, go to step 12. Step 12: Calculate the absolute velocity magnitudes of the original point trace and the point trace to be associated. ; Step Thirteen, Judgment Does it meet the requirements? If the condition is met, proceed to step fourteen; otherwise, proceed to step ten. Step 14: Establish temporary tracks for the original points and the points to be associated.

2. The method for establishing a temporary track for an air search radar as described in claim 1, characterized in that, The coarse-grained division divides the 360° circumference into N uniform sectors, while the fine-grained division divides the 360° circumference into 2N uniform sectors. Assuming the minimum range of interest for the air search radar is The maximum distance is The maximum speed of the trackable target is The time taken for a radar scan to complete one cycle is calculated according to the chord length formula: ； At the radar's minimum range of interest, the maximum angle the target can move within a full radar scan is: ； So, the sector angle of coarse-grained partitioning fine-grained sector angle In the case of fine-grained sector division, the minimum range that the radar needs to focus on is: 。 3. The method for establishing a temporary track for an air search radar as described in claim 2, characterized in that, In step one, the angle of the coarse-grained sector is calculated as follows: Optimal The calculation formula is ； The unit is °. Since the number of coarse-grained sectors must be an integer, the number of sectors is: ； So, for The corrected calculation formula is as follows: 。 4. The method for establishing a temporary track for an air search radar as described in claim 1, characterized in that, Step three, minimum radar range of interest The calculation formula is as follows; 。 5. The method for establishing a temporary track for an air search radar as described in claim 4, characterized in that, Step four records the sector indices of the original trace in both the coarse-grained and fine-grained partitions, where the coarse-grained index value is... Fine-grained index value .

6. The method for establishing a temporary track for an air search radar as described in claim 5, characterized in that, The original dots in step six come from the first dot of this frame. Each sector, denoted as All the points to be associated come from the original points of sectors k-1, k, and k+1 in the previous frame's coarse-grained division, denoted as .

7. The method for establishing a temporary track for an air search radar as described in claim 6, characterized in that, Step nine involves extracting the set of traces to be associated and determining the original traces. distance Minimum range of interest for radar under fine-grained classification The relationship; if Then the unassociated traces of this original trace come from the set of all unassociated traces. ; Otherwise, based on the original dot pattern Extracting from the finely divided sector index g. Points with sector indices of g-1, g, or g+1 under fine-grained partitioning are considered as points to be associated. For ease of representation, the final extracted points to be associated are uniformly represented as follows: .

8. The method for establishing a temporary track for an air search radar as described in claim 7, characterized in that, The absolute velocity magnitude in step twelve The specific calculation formula is as follows: ； The unit is meters per second.

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