Airborne wind shear radar adaptive outlier velocity point suppression method and device

Abstract

The invention relates to the technical field of airborne meteorological radars, and discloses an airborne wind shear radar adaptive outlier speed point suppression method and device, and the method comprises the steps: dynamically adjusting the adaptive threshold value of each sliding window according to the spectral width, judging a speed outlier and a speed effective point through a deviation normalized value and the adaptive threshold value, and carrying out the local interpolation restoration, thereby achieving the adaptive outlier speed point suppression of the airborne wind shear radar. According to the method, the speed outliers are accurately eliminated, real signal features are reserved, error diffusion is avoided, the wind shear risk factor calculation precision is improved, and the detection reliability of the airborne meteorological radar in a complex environment is enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of airborne weather radar, and discloses an airborne wind shear radar adaptive outlier velocity point suppression method and device. BACKGROUND

[0002] When the airborne weather radar detects low-altitude wind shear in the take-off and landing stage, the ground clutter is widely distributed, strong, and the spectrum is expanded during the movement of the radar platform, so that the wind shear target is submerged. If the clutter suppression is not complete, the wind speed estimation result will be inaccurate, and then the subsequent wind shear detection and alarm will be affected, which will seriously affect the judgment and decision of the pilot.

[0003] The airborne weather radar mainly evaluates the risk of the wind shear event through a dangerous factor (i.e., F factor). The calculation of this factor depends on parameters such as velocity and velocity gradient. However, in order to solve the influence of ground clutter on wind shear target detection caused by the downward-looking of the airborne wind shear radar, the existing algorithm usually uses a sliding average algorithm of adjacent cells to reduce the influence of ground clutter, and the final determination value of the F factor, i.e., the average F factor, is also a sliding average value of the F factor corresponding to a one-kilometer distance gate. However, the sliding average involved in it reduces the interference of some outliers on the final result at the cost of a large number of samples. It will spread the velocity outlier error caused by the ground clutter to the entire sliding window, which reduces the detection accuracy of the wind shear target to some extent, especially in the scene with low signal-to-clutter ratio. SUMMARY

[0004] The purpose of the present application is to provide an airborne wind shear radar adaptive outlier velocity point suppression method and device, which can accurately remove abnormal velocity points and retain true signal characteristics, avoid error diffusion, improve the calculation accuracy of the wind shear dangerous factor, and enhance the detection reliability of the airborne weather radar in complex environments.

[0005] In order to achieve the above technical effects, the technical solution adopted by the present application is: An airborne wind shear radar adaptive outlier velocity point suppression method comprises: According to the detection echo of the airborne wind shear radar on the wind shear target, a velocity vector and a spectral width vector corresponding to each azimuth line in a scanning line are obtained. The velocity vector is composed of the velocity of each range gate on each azimuth line data, and the spectral width vector is composed of the spectral width of each range gate on each azimuth line data. A azimuth line is selected as the analysis object. A sliding window with a preset length and movement step size is used to traverse all distance gates on the azimuth line at the preset step size. Each time the sliding window stops at a step, the deviation normalization value of the velocity of the center distance gate in the current window is analyzed using the Z-Score formula. Then, based on the velocity and spectral width of all distance gates in the current window, the average spectral width, average velocity, and standard deviation of all distance gates in the current window are determined. The adaptive threshold of the current window is calculated by combining the average spectral width, average velocity, and standard deviation of the velocity. The deviation normalization value is compared with the adaptive threshold. If the deviation normalization value is greater than the adaptive threshold, the velocity of the center distance gate in the current window is marked as a velocity outlier; otherwise, it is marked as a velocity valid point. The velocity of the velocity outlier is assigned and repaired using a linear interpolation formula to obtain the repaired velocity of the velocity outlier, and the velocity vector corresponding to the azimuth line is updated. Traverse all azimuth lines in the scan row to obtain the updated velocity vector for each azimuth line.

[0006] Furthermore, through Calculate the normalized deviation of the center distance from the gate velocity within the current sliding window; where: This is the normalized value of the deviation; The speed at which the center of the sliding window is currently located relative to the door; This is the index of the center distance from the door within the current sliding window; This is the median of all distance-to-gate velocity values ​​within the current sliding window; This represents the standard deviation of all distance-to-door velocities within the current sliding window; This is the preset minimum correction value.

[0007] Furthermore, through Calculate the adaptive threshold for the current sliding window; where, This is a preset proportional coefficient; This represents the average spectral width of the distance to the gate within the current sliding window; This represents the average speed of the distance from the door within the current sliding window; This represents the standard deviation of all distance gate velocities within the current sliding window.

[0008] Furthermore, the velocity after the velocity outlier repair is obtained through... Calculated This represents the distance gate index value corresponding to the velocity outlier. This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the left is... The index value of the distance gate, This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the right is... The index value of the distance gate, the velocity of the distance gate with index value , the velocity of the distance gate with index value , the velocity of the distance gate with index value ,

[0009] Further, when the velocity outlier is located at the end point of the velocity vector and only one end point is the velocity outlier, the velocity of the velocity valid point closest to the velocity outlier is assigned to the velocity outlier.

[0010] Further, when consecutive velocity values at the left end of the velocity vector are velocity outliers, and the velocity value immediately to the right of the , velocity value is a velocity valid value, wherein , the consecutive velocity values at the left end of the velocity vector are repaired by , wherein: is the new velocity estimate of the velocity outlier at the left end of the velocity vector, ; is the velocity value at the left end of the velocity vector, , is the velocity value at the left end of the velocity vector, ; is the velocity value at the left end of the velocity vector, ; when consecutive velocity values at the right end of the velocity vector are velocity outliers, and the velocity value immediately to the left of the , velocity value is a velocity valid value, wherein , the consecutive velocity values at the right end of the velocity vector are repaired by , wherein: is the new velocity estimate of the velocity outlier of the velocity vector, , is the total number of velocity values of the velocity vector; is the velocity value at the right end of the velocity vector, , is the velocity value at the right end of the velocity vector, ; is the velocity value at the right end of the velocity vector, .

[0011] An adaptive outlier velocity point suppression device for airborne wind shear radar, used to implement the aforementioned adaptive outlier velocity point suppression method for airborne wind shear radar, comprising: The velocity spectral width calculation module is used to obtain the velocity vector and spectral width vector corresponding to each azimuth line in a scan row based on the detection echo of the airborne wind shear radar to the wind shear target; the velocity vector is composed of the velocity of each range gate on each azimuth line data, and the spectral width vector is composed of the spectral width of each range gate on each azimuth line data. The sliding window outlier detection and marking module selects an azimuth line as the analysis object and uses a sliding window of preset length and step size to traverse all distance gates on the azimuth line at preset step sizes. At each step the sliding window stops, it first analyzes the normalized deviation value of the velocity of the center distance gate within the current window using the Z-Score formula. Then, based on the velocity and spectral width of all distance gates within the current window, it determines the average spectral width, average velocity, and standard deviation of all distance gates within the current window. Combining the average spectral width, average velocity, and standard deviation, it calculates the adaptive threshold for the current window. It compares the normalized deviation value with the adaptive threshold. If the normalized deviation value is greater than the adaptive threshold, the velocity of the center distance gate within the current window is marked as a velocity outlier; otherwise, it is marked as a valid velocity point. The interpolation repair module is used to assign and repair the velocity of the velocity outlier point using a linear interpolation formula, obtain the repaired velocity of the velocity outlier point, and update the velocity vector corresponding to the azimuth line. The traversal module is used to traverse all azimuth lines in the scan line and obtain the updated velocity vector for each azimuth line.

[0012] Furthermore, through Calculate the normalized deviation of the center distance from the gate velocity within the current sliding window; where: This is the normalized value of the deviation; The speed at which the center of the sliding window is currently located relative to the door; This is the index of the center distance from the door within the current sliding window; This is the median of all distance-to-gate velocity values ​​within the current sliding window; This represents the standard deviation of all distance-to-door velocities within the current sliding window; This is the preset minimum correction value.

[0013] Furthermore, through Calculate the adaptive threshold for the current sliding window; where, This is a preset proportional coefficient; This represents the average spectral width of the distance to the gate within the current sliding window; This represents the average speed of the distance from the door within the current sliding window; This represents the standard deviation of all distance gate velocities within the current sliding window.

[0014] Furthermore, the velocity after the velocity outlier repair is obtained through... Calculated This represents the distance gate index value corresponding to the velocity outlier. This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the left is... The index value of the distance gate, This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the right is... The index value of the distance gate, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The distance to the speed after the door is repaired.

[0015] Compared with the prior art, the beneficial effects of this invention are: This invention dynamically adjusts the adaptive threshold of each sliding window based on the spectral width, determines velocity outliers and effective velocity points by using the deviation normalization value and the adaptive threshold, and then combines local interpolation repair to accurately remove velocity outliers while retaining true signal characteristics. This avoids error propagation, improves the accuracy of wind shear hazard factor calculation, and enhances the detection reliability of airborne weather radar in complex environments. Attached Figure Description

[0016] Figure 1 This is a flowchart of the adaptive outlier velocity point suppression method for airborne wind shear radar in this invention; Figure 2 The present invention compares the velocity information obtained directly using the FFT method with the theoretical velocity value of the scan azimuth line; Figure 3 The present invention is compared with the F-factor calculated directly using the FFT method and the theoretical F-factor of the scan azimuth line; Figure 4 This is a structural diagram of the adaptive outlier velocity point suppression device for airborne wind shear radar in this invention. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0018] Example 1 See Figure 1An adaptive outlier velocity point suppression method for airborne wind shear radar, comprising: Based on the detection echo of the airborne wind shear radar of the wind shear target, a velocity vector and a spectral width vector corresponding to each azimuth line in a scan row are obtained; the velocity vector is composed of the velocity of each range gate on each azimuth line data, and the spectral width vector is composed of the spectral width of each range gate on each azimuth line data. A azimuth line is selected as the analysis object. A sliding window with a preset length and movement step size is used to traverse all distance gates on the azimuth line at the preset step size. Each time the sliding window stops at a step, the deviation normalization value of the velocity of the center distance gate in the current window is analyzed using the Z-Score formula. Then, based on the velocity and spectral width of all distance gates in the current window, the average spectral width, average velocity, and standard deviation of all distance gates in the current window are determined. The adaptive threshold of the current window is calculated by combining the average spectral width, average velocity, and standard deviation of the velocity. The deviation normalization value is compared with the adaptive threshold. If the deviation normalization value is greater than the adaptive threshold, the velocity of the center distance gate in the current window is marked as a velocity outlier; otherwise, it is marked as a velocity valid point. The velocity of the velocity outlier is assigned and repaired using a linear interpolation formula to obtain the repaired velocity of the velocity outlier, and the velocity vector corresponding to the azimuth line is updated. Traverse all azimuth lines in the scan row to obtain the updated velocity vector for each azimuth line.

[0019] This invention dynamically adjusts the adaptive threshold of each sliding window based on the spectral width. It determines velocity outliers and valid velocity points by comparing the deviation normalization value with the adaptive threshold. Combined with local interpolation repair, it accurately removes velocity outliers while preserving true signal characteristics, avoiding error propagation, improving the accuracy of wind shear hazard factor calculation, and enhancing the reliability of airborne weather radar in complex environments. Example 2 See Figure 1 An adaptive outlier velocity point suppression method for airborne wind shear radar, comprising: Step 1: Based on the detection echo of the airborne wind shear radar of the wind shear target, obtain the velocity vector and spectral width vector corresponding to each azimuth line in a scan row; the velocity vector is composed of the velocity of each range gate on each azimuth line data, and the spectral width vector is composed of the spectral width of each range gate on each azimuth line data.

[0020] Specifically, in the wind shear mode of the airborne weather radar, the detection echo of the wind shear target is acquired, and the velocity at each range gate on each azimuth line is calculated using the FFT method, thus obtaining the velocity vector corresponding to each azimuth line. Using classic spectral estimation algorithms, the spectral width corresponding to each azimuth line can be calculated, resulting in a spectral width vector for each azimuth line. , This represents the total number of range gates on each azimuth line. For example, assuming each azimuth line has 70 range gates, then each azimuth line can obtain a 1×70 velocity vector. ,in Indicates the first The velocity corresponding to each distance gate. Furthermore, using classic spectral estimation algorithms, the spectral width information corresponding to each azimuth line can be calculated. ,in Reflecting the The signal frequency width corresponding to each distance gate.

[0021] Step 2: Select an azimuth line as the analysis object, and use a sliding window with a preset length and step size to traverse all distance gates on the azimuth line at the preset step size. Each time the sliding window stops at a step, first analyze the normalized deviation value of the velocity of the center distance gate within the current window using the Z-Score formula; then, based on the velocity and spectral width of all distance gates within the current window, determine the average spectral width, average velocity, and standard deviation of all distance gates within the current window. Combine the average spectral width, average velocity, and standard deviation of the velocity to calculate the adaptive threshold of the current window; compare the normalized deviation value with the adaptive threshold. If the normalized deviation value is greater than the adaptive threshold, mark the velocity of the center distance gate within the current window as a velocity outlier; otherwise, mark it as a velocity valid point. Specifically, first, select a azimuth line as the analysis object and configure a sliding window: set the length of the sliding window W to M=5, and traverse all speeds corresponding to distances from doors along the azimuth line in steps of 1. For example, suppose the sliding window moves to step 45, and the corresponding sliding window... The center velocity point is Then the sliding window It can be represented as .

[0022] Secondly, for each step the sliding window takes, the normalized deviation of the center distance from the door velocity within the current window is analyzed using the Z-Score formula. Calculate the normalized deviation of the center distance from the gate velocity within the current sliding window; where: The speed at which the center of the sliding window is currently located relative to the door; This is the index of the center distance from the door within the current sliding window; This is the preset minimum correction value; This is the median of all distance-to-gate velocity values ​​within the current sliding window; This represents the standard deviation of all distance-to-door velocities within the current sliding window; The speed of the center distance from the door within the current sliding window. Median within the window The deviation normalization value. In this embodiment, when calculating the deviation normalization value of the center distance to the door speed within the current window, a preset minimum correction value is added to the denominator of the formula. To avoid a denominator of zero, the median of all distance-to-gate velocity values ​​within the current sliding window is used. It participates in the calculation to enhance robustness to outliers.

[0023] Then, through Calculate the adaptive threshold for the current sliding window; where: This is the adaptive threshold for the current sliding window; This is a preset proportional coefficient; This represents the average spectral width of the distance to the gate within the current sliding window; This represents the average speed of the distance from the door within the current sliding window; This represents the standard deviation of the speed at all distances from the door within the current sliding window. It should be noted that the preset scaling factor... Before formally applying this method, several azimuth lines can be selected from a scan line. The data corresponding to the selected azimuth lines can then be substituted into... The proportionality coefficient is obtained by fitting. Value, the proportionality coefficient The value applies to the entire scan line.

[0024] Finally, compare the normalized deviation value of the current sliding window with the adaptive threshold. If Then mark the speed of the center of the current window from the door. If a point is an outlier in the velocity range, it is marked as an effective velocity point or left unmarked.

[0025] In this step, the adaptive threshold As the clutter environment changes in real time, the system automatically raises the judgment threshold adaptively in the event of strong clutter. In the event of a clean signal, the threshold will be automatically lowered for adaptive adjustment. To avoid missed judgments.

[0026] Step 3: Use a linear interpolation formula to assign and repair the velocity of the velocity outlier, obtain the repaired velocity of the velocity outlier, and update the velocity vector corresponding to the azimuth line.

[0027] Specifically, assuming the first The velocity marker of the distance gate is designated as a velocity outlier. Then, interpolation is performed on this velocity outlier, and the value of the first outlier is taken as the first value. The neighboring door on the left side of the distance door speed , No. The neighboring distance door to the right of the distance door speed As the basis for interpolation, they are substituted into the linear interpolation formula. Calculate and obtain the velocity after the velocity outlier is repaired; where, This represents the distance gate index value corresponding to the velocity outlier. This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the left is... The index value of the distance gate, This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the right is... The index value of the distance gate, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The speed after the distance to the repaired door, These are the weighting coefficients.

[0028] Step 4: Boundary Case Handling: When the velocity outlier is located at one end of the velocity vector and only one end is an outlier, the velocity of the nearest valid velocity point to the outlier is assigned to the outlier. When multiple consecutive velocity outliers appear at the ends of the velocity vector, interpolation is performed using the next nearest valid point.

[0029] Specifically, regarding the handling of outliers at a single endpoint: when the velocity outlier is located within the velocity vector... The endpoints and only one endpoint is an outlier, i.e. or hour, If the length of the velocity vector is given, then the velocity of the effective velocity point closest to the velocity outlier is assigned to the velocity outlier. For example, if Corresponding speed For velocity outliers, the distance from velocity outliers is... The nearest effective speed point is Then let ;like corresponding speed For velocity outliers, the distance from velocity outliers is... The nearest effective speed point is Then let .

[0030] For handling outliers at continuous endpoints: (1) When in the velocity vector A continuous line appears at the left end. There are velocity outliers, and the velocity value is... The adjacent one to the right , Each speed value is an effective speed value, among which The front of the left end of the velocity vector Each speed value passes through Repairs were carried out, including: The first part of the velocity vector at the left end New velocity estimates for velocity outliers ; The first part of the velocity vector at the left end A speed value, , The first part of the velocity vector at the left end A speed value, For example, when When =3, the velocity vector Three consecutive velocity outliers appear at the left end, namely... , , ,and The first and second adjacent rightward velocity values ​​are valid values, i.e. 、 If the velocity is the effective value, then the velocity outlier is... pass Repair, speed outlier points pass Repair, speed outlier points pass Repairs will be carried out.

[0031] (2) When in the velocity vector A continuous line appears at the right end. There are velocity outliers, and the velocity value is... The adjacent left , When each speed value is the effective speed value, among which The right end of the velocity vector is continuous Each velocity value is passed through Repairs will be carried out, including: The velocity vector is the first New velocity estimates for velocity outliers , The total number of velocity values ​​in the velocity vector; The right end of the velocity vector A speed value, , The right end of the velocity vector A speed value, For example, when At that time, the velocity vector Three consecutive velocity outliers appear at the right end, namely... , , ,and The first and second velocity values ​​immediately to the left , If the velocity is the effective value, then the velocity outlier is... pass Repairing and re-estimating the velocity of outliers. '、 The calculation method is the same.

[0032] Step 5: Traverse all azimuth lines in the scan row to obtain the updated velocity vector for each azimuth line.

[0033] Specifically, traverse the entire velocity vector of the azimuth line described in step two: repeat steps two, three, four, and five above to complete the traversal and identification of all velocity outliers in the radar echo of a scanning azimuth line, until all outliers in the entire velocity vector are repaired, finally obtaining an optimized velocity vector without velocity outliers. Then, iterates through all azimuth lines in the row to obtain the updated velocity vector for each azimuth line. This updated vector is used for subsequent calculations of wind shear hazard factors, velocity gradients, and other parameters, thereby improving the reliability of the input data for the wind shear detection algorithm. In this embodiment, the corrected velocity vector without velocity outliers is shown below. Figure 2 As shown, the calculated F-factor results are as follows: Figure 3 As shown. Figure 2 This document compares the velocity information obtained using the present invention with that obtained directly using the FFT method, and the theoretical velocity value of the scan azimuth line. Figure 3 This invention compares the F-factor obtained by directly using the FFT method with the theoretical F-factor of the scan azimuth line. The solid line represents the new prediction speed obtained using the method of this embodiment, while the dashed line represents the original algorithm speed obtained using the existing FFT method. Figure 2 and Figure 3 As can be seen, the adaptive outlier velocity point suppression method of airborne wind shear radar in this embodiment can accurately distinguish between velocity outliers and effective velocity points, accurately remove velocity outliers and retain true signal characteristics.

[0034] This invention employs a spectral width correlation detection mechanism, through spectral width The velocity deviation is normalized to obtain the deviation normalization value. Then, combined with the adaptive threshold, the velocity outlier point and the velocity effective point are accurately distinguished, that is, the ground clutter and wind shear target are accurately distinguished, so as to improve the detection accuracy of wind shear target in strong clutter environment.

[0035] In the second step of velocity outlier detection, the present invention dynamically adjusts the adaptive threshold of each sliding window according to the spectral width. Moreover, the threshold is dynamically adjusted based on local statistics and working mode, without the need for preset empirical parameters, and is compatible with different detection scenarios, such as strong near-field clutter during takeoff and clean far-field signals during cruise.

[0036] This invention employs median deviation calculation and linear interpolation repair to limit the influence range of a single outlier to within two neighboring distance gates. Compared with the traditional 5-point smoothing algorithm, the error diffusion area of ​​this invention is reduced by 60%, demonstrating a better error diffusion suppression effect.

[0037] Based on the same inventive concept, see [link to inventive concept] Figure 4 This embodiment also provides an adaptive outlier velocity point suppression device for airborne wind shear radar, used to implement the aforementioned adaptive outlier velocity point suppression method for airborne wind shear radar, comprising: The velocity spectral width calculation module is used to obtain the velocity vector and spectral width vector corresponding to each azimuth line in a scan row based on the detection echo of the airborne wind shear radar to the wind shear target; the velocity vector is composed of the velocity of each range gate on each azimuth line data, and the spectral width vector is composed of the spectral width of each range gate on each azimuth line data. The sliding window outlier detection and marking module selects an azimuth line as the analysis object and uses a sliding window of preset length and step size to traverse all distance gates on the azimuth line at preset step sizes. At each step the sliding window stops, it first analyzes the normalized deviation value of the velocity of the center distance gate within the current window using the Z-Score formula. Then, based on the velocity and spectral width of all distance gates within the current window, it determines the average spectral width, average velocity, and standard deviation of all distance gates within the current window. Combining the average spectral width, average velocity, and standard deviation, it calculates the adaptive threshold for the current window. It compares the normalized deviation value with the adaptive threshold. If the normalized deviation value is greater than the adaptive threshold, the velocity of the center distance gate within the current window is marked as a velocity outlier; otherwise, it is marked as a valid velocity point. The interpolation repair module is used to assign and repair the velocity of the velocity outlier point using a linear interpolation formula, obtain the repaired velocity of the velocity outlier point, and update the velocity vector corresponding to the azimuth line. The traversal module is used to traverse all azimuth lines in the scan line and obtain the updated velocity vector for each azimuth line.

[0038] In this embodiment, by Calculate the normalized deviation of the center distance from the gate velocity within the current sliding window; where: This is the normalized value of the deviation; The speed at which the center of the sliding window is currently located relative to the door; This is the index of the center distance from the door within the current sliding window; This is the median of all distance-to-gate velocity values ​​within the current sliding window; This represents the standard deviation of all distance-to-door velocities within the current sliding window; This is the preset minimum correction value.

[0039] In this embodiment, by Calculate the adaptive threshold for the current sliding window; where, This is a preset proportional coefficient; This represents the average spectral width of the distance to the gate within the current sliding window; This represents the average speed of the distance from the door within the current sliding window; This represents the standard deviation of all distance gate velocities within the current sliding window.

[0040] In this embodiment, the velocity after the velocity outlier point repair is obtained through... Calculated This represents the distance gate index value corresponding to the velocity outlier. This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the left is... The index value of the distance gate, This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the right is... The index value of the distance gate, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The distance to the speed after the door is repaired.

[0041] Traditional outlier detection methods often employ fixed thresholds, such as the Z-score method, but fail to consider the spectral differences between wind shear targets and ground clutter. Wind shear targets exhibit a wider spectral width, while ground clutter, such as topographic echoes, typically has a narrower spectral width. Because traditional outlier detection methods lack utilization of spectral width characteristics, they are prone to misidentification or underidentification in complex clutter environments, leading to increased errors in the calculation of wind shear hazard factors.

[0042] Therefore, this invention utilizes the distribution differences in spectral width characteristics between wind shear targets and ground clutter to suppress wind shear clutter in complex terrain, thereby improving the robustness of the algorithm. Moreover, by using spectral width weighting and dynamic thresholding, it significantly improves the detection accuracy of wind shear targets in complex scenarios, avoiding the "one-size-fits-all" defects of traditional methods.

[0043] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An adaptive outlier velocity point suppression method for airborne wind shear radar, characterized in that, include: Based on the detection echo of the airborne wind shear radar to the wind shear target, the velocity vector and spectral width vector corresponding to each azimuth line in a scan row are obtained. The velocity vector is composed of the velocity of each range gate on each azimuth line data, and the spectral width vector is composed of the spectral width of each range gate on each azimuth line data. A azimuth line is selected as the analysis object. A sliding window with a preset length and movement step size is used to traverse all distance gates on the azimuth line at the preset step size. Each time the sliding window stops at a step, the deviation normalization value of the velocity of the center distance gate in the current window is first analyzed using the Z-Score formula. Then, based on the velocity and spectral width of all distance gates in the current window, the average spectral width, average velocity, and standard deviation of all distance gates in the current window are determined. The adaptive threshold of the current window is calculated by combining the average spectral width, average velocity, and standard deviation of the velocity. The deviation normalization value is compared with the adaptive threshold. If the deviation normalization value is greater than the adaptive threshold, the velocity of the center distance gate in the current window is marked as a velocity outlier; otherwise, it is marked as a velocity valid point. The velocity of the velocity outlier is assigned and repaired using a linear interpolation formula to obtain the repaired velocity of the velocity outlier, and the velocity vector corresponding to the azimuth line is updated. Traverse all azimuth lines in the scan row to obtain the updated velocity vector for each azimuth line.

2. The adaptive outlier velocity point suppression method for airborne wind shear radar according to claim 1, characterized in that, pass Calculate the normalized deviation of the center distance from the gate velocity within the current sliding window; where: This is the normalized value of the deviation; The speed at which the center of the sliding window is currently located relative to the door; This is the index of the center distance from the door within the current sliding window; This is the median of all distance-to-gate velocity values ​​within the current sliding window; This represents the standard deviation of all distance-to-door velocities within the current sliding window; This is the preset minimum correction value.

3. The adaptive outlier velocity point suppression method for airborne wind shear radar according to claim 2, characterized in that, pass Calculate the adaptive threshold for the current sliding window; where, This is a preset proportional coefficient; This represents the average spectral width of the distance to the gate within the current sliding window; This represents the average speed of the distance from the door within the current sliding window; This represents the standard deviation of all distance gate velocities within the current sliding window.

4. The adaptive outlier velocity point suppression method for airborne wind shear radar according to claim 1, characterized in that, The velocity after outlier repair is passed through Calculated This represents the distance gate index value corresponding to the velocity outlier. This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the left is... The index value of the distance gate, This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the right is... The index value of the distance gate, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The distance to the speed after the door is repaired.

5. The adaptive outlier velocity point suppression method for airborne wind shear radar according to claim 1, characterized in that, When the velocity outlier is located at an endpoint of the velocity vector and there is only one endpoint that is an outlier, the velocity of the nearest valid velocity point to the velocity outlier is assigned to the velocity outlier.

6. The adaptive outlier velocity point suppression method for airborne wind shear radar according to claim 5, characterized in that, When continuous velocity vector appears at the left end There are velocity outliers, and the velocity value is... The right-hand adjacent number , Each speed value is an effective speed value, among which The front of the left end of the velocity vector Each speed value passes through Repairs were carried out, including: The first part of the velocity vector at the left end New velocity estimates for velocity outliers ; The first part of the velocity vector at the left end A speed value, , The first part of the velocity vector at the left end A speed value, ; When continuous velocity vector appears at the right end There are velocity outliers, and the velocity value is... The adjacent left , When each speed value is the effective speed value, among which The right end of the velocity vector is continuous Each speed value passes through Repairs were carried out, including: The velocity vector is the first New velocity estimates for velocity outliers , The total number of velocity values ​​in the velocity vector; The right end of the velocity vector A speed value, , The right end of the velocity vector is the first A speed value, .

7. An adaptive outlier velocity point suppression device for airborne wind shear radar, used to implement the adaptive outlier velocity point suppression method for airborne wind shear radar according to any one of claims 1-6, characterized in that, include: The velocity spectral width calculation module is used to obtain the velocity vector and spectral width vector corresponding to each azimuth line in a scan row based on the detection echo of the airborne wind shear radar to the wind shear target; the velocity vector is composed of the velocity of each range gate on each azimuth line data, and the spectral width vector is composed of the spectral width of each range gate on each azimuth line data. The sliding window outlier detection and marking module selects an azimuth line as the analysis object and uses a sliding window of preset length and step size to traverse all distance gates on the azimuth line at preset step sizes. At each step the sliding window stops, it first analyzes the normalized deviation value of the velocity of the center distance gate within the current window using the Z-Score formula. Then, based on the velocity and spectral width of all distance gates within the current window, it determines the average spectral width, average velocity, and standard deviation of all distance gates within the current window. Combining the average spectral width, average velocity, and standard deviation, it calculates the adaptive threshold for the current window. It compares the normalized deviation value with the adaptive threshold. If the normalized deviation value is greater than the adaptive threshold, the velocity of the center distance gate within the current window is marked as a velocity outlier; otherwise, it is marked as a valid velocity point. The interpolation repair module is used to assign and repair the velocity of the velocity outlier point using a linear interpolation formula, obtain the repaired velocity of the velocity outlier point, and update the velocity vector corresponding to the azimuth line. The traversal module is used to traverse all azimuth lines in the scan line and obtain the updated velocity vector for each azimuth line.

8. The airborne wind shear radar adaptive outlier velocity point suppression device according to claim 7, characterized in that, pass Calculate the normalized deviation of the center distance from the gate velocity within the current sliding window; where: This is the normalized value of the deviation; The speed at which the center of the sliding window is currently located relative to the door; This is the index of the center distance from the door within the current sliding window; This is the median of all distance-to-gate velocity values ​​within the current sliding window; This represents the standard deviation of all distance-to-door velocities within the current sliding window; This is the preset minimum correction value.

9. The airborne wind shear radar adaptive outlier velocity point suppression device according to claim 8, characterized in that, pass Calculate the adaptive threshold for the current sliding window; where, This is a preset proportional coefficient; This represents the average spectral width of the distance to the gate within the current sliding window; This represents the average speed of the distance from the door within the current sliding window; This represents the standard deviation of all distance gate velocities within the current sliding window.

10. The airborne wind shear radar adaptive outlier velocity point suppression device according to claim 9, characterized in that, The velocity after outlier repair is passed through Calculated This represents the distance gate index value corresponding to the velocity outlier. This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the left is... The index value of the distance gate, This indicates that the distance gate corresponding to the velocity outlier point is used as the starting point, and the distance to the right is... The index value of the distance gate, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The speed of the distance to the door, Indicates that the index value is The distance to the speed after the door is repaired.

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