Weather radar calibration method, device, equipment and storage medium

Abstract

Embodiments of the present disclosure provide a weather radar calibration method, device, equipment and storage medium, which are applied to the technical field of radar calibration. The method comprises one-dimensional profile fitting on maximum intensity values of a distance direction, an azimuth direction and a pitch direction of an obtained target sampling point to obtain corresponding fitting values; based on a pre-designed calculation formula, corresponding beam width values, beam center values and amplitude maximum values are respectively calculated according to the fitting values; then, parabolic fitting is performed on the distance to obtain the amplitude maximum value on the distance profile, and then two-dimensional surface fitting is performed on the amplitude maximum values of different azimuths and pitches to finally determine the actual maximum amplitude value corresponding to the metal ball. In this way, the accuracy and practicability of the metal ball calibration can be significantly improved.

Description

Technical Field

[0001] This disclosure relates to the field of data processing technology, and more particularly to the field of radar calibration technology, specifically to a weather radar calibration method, apparatus, equipment, and storage medium. Background Technology

[0002] Weather radar metal sphere calibration is a process of calibrating and verifying a weather radar system by using a metal sphere as a standard reflector. The main purpose of this process is to ensure that the radar system can accurately measure the intensity, extent, and other meteorological parameters of precipitation. Although the metal sphere is a point target, during calibration, there are no other targets filling the radar beam, making it a reasonable substitute for meteorological target calibration. Generally, a metal sphere of known size is suspended using a drone, airship, balloon, kite, etc., ensuring that the metal sphere is at least twice the far-field distance from the radar. This guarantees both theoretical compliance with the requirements of far-field electromagnetic wave detection and sufficient radar beam coverage. When the metal sphere enters the weather radar's detection beam area, the radar can detect the backscattered signal from the metal sphere. Since the radar cross section (RCS) of the metal sphere is known, using a metal sphere for reflectivity calibration of the weather radar is feasible.

[0003] The core issue in weather radar metal sphere calibration is how to accurately obtain the true maximum amplitude value of the metal sphere. Current methods directly use the maximum intensity value obtained from sampling points as the maximum amplitude value in metal sphere calibration.

[0004] Specifically, the current technical solution for obtaining the maximum amplitude value in the calibration of a metal ball for weather radar includes: determining the azimuth information of the metal ball relative to the weather radar based on the latitude and longitude of the UAV and the desired flight altitude, and controlling the radar antenna of the weather radar to point to the azimuth information; during the process of the UAV carrying the metal ball to the desired flight altitude, controlling the weather radar to scan the metal ball in the pitch direction to obtain pitch scan data and obtain the precise pitch angle of the metal ball echo; then controlling the weather radar to scan the metal ball in the azimuth direction to obtain azimuth scan data and obtain the precise azimuth angle of the metal ball echo; finally, controlling the radar antenna of the weather radar to point to the azimuth corresponding to the reference pitch angle and reference azimuth angle, controlling the UAV to continuously move the position of the suspended metal ball so that the metal ball is in the middle position of the radar beam and range library; at the same time, based on the intensity analysis method and the position analysis method, the metal ball is scanned in real time to obtain the metal ball calibration data. The intensity analysis method includes: by reading the baseline data of the UAV metal ball experiment, the intensity distribution of the metal ball at different azimuth angles is obtained. A point with the highest pre-filter reflectivity factor in the range database can be automatically retrieved; this point is the target point of the metal ball. The pre-filter reflectivity factor, azimuth angle, pitch angle, and position parameters of this point are recorded. However, in reality, the metal ball may not fall exactly on a particular sampling point. This makes it impossible to find the actual maximum amplitude value on the range profile, thus significantly impacting the accuracy and practicality of the metal ball calibration.

[0005] In other words, the above-mentioned technical solution has two main drawbacks. First, the metal ball calibration process requires the UAV-suspended metal ball to move continuously to ensure it is positioned between the radar beam and the range database, thereby accurately acquiring the calibration data. However, since the UAV is manually controlled, it is difficult to guarantee such precise positioning in actual operation. In practice, it has been found that the metal ball often cannot be located exactly at the center of the range database. Second, the current solution directly uses the point with the highest pre-filter reflectivity factor in the range database as the target point for the metal ball. In reality, the metal ball may not fall exactly on a sampling point, which makes it impossible to find the actual maximum amplitude value on the range profile, thus significantly affecting the accuracy and practicality of the metal ball calibration. Therefore, an effective solution is needed to address the issue of the metal ball not being located exactly at the center of the range database. Summary of the Invention

[0006] This disclosure provides a weather radar calibration method, apparatus, device, and storage medium.

[0007] According to a first aspect of this disclosure, a weather radar calibration method is provided. The method includes:

[0008] Obtain the maximum intensity value in the distance direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction of the target sampling point;

[0009] One-dimensional profile fitting is performed based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction.

[0010] Based on the preset calculation formula, according to the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction, the beamwidth and beam center values ​​in the range direction, the beamwidth and beam center values ​​in the pitch direction, the beamwidth, beam center value, and maximum amplitude value in the azimuth direction are calculated respectively.

[0011] Calculate the average value of the beamwidth and beamcenter in the range of the preset maximum amplitude value to obtain the beamwidth and beamcenter results in the range direction.

[0012] Based on a preset Gaussian surface fitting algorithm, Gaussian surface fitting is performed according to the beamwidth and beam center values ​​in the pitch direction, the beamwidth and beam center values ​​in the azimuth direction, and the maximum amplitude value to obtain a two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

[0013] Based on the two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions, the transmission gap is corrected to obtain a one-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

[0014] Gaussian surface fitting is performed based on the one-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions to obtain the beamwidth and beam center results in the pitch direction, the beamwidth and beam center results in the azimuth direction, and the maximum amplitude results.

[0015] The actual maximum amplitude is calculated based on the beamwidth and beamcenter results in the range direction, the beamwidth and beamcenter results in the pitch direction, the beamwidth and beamcenter results in the azimuth direction, and the maximum amplitude result.

[0016] In addition to the aspects and any possible implementations described above, a further implementation is provided where the number of target sampling points is greater than or equal to a preset number;

[0017] The step of performing one-dimensional profile fitting based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the range direction fitted value, the azimuth direction fitted value, and the pitch direction fitted value includes:

[0018] Based on the polynomial curve fitting function, a one-dimensional profile is fitted according to the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction.

[0019] In addition to the aspects and any possible implementations described above, a further implementation is provided where the number of target sampling points is less than the preset number;

[0020] The step of performing one-dimensional profile fitting based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the range direction fitted value, the azimuth direction fitted value, and the pitch direction fitted value includes:

[0021] Obtain the sampling points in the distance library preceding and / or following the distance library containing the maximum intensity value in the distance direction of the target sampling point, and also use them as target sampling points, so that the number of target sampling points is greater than or equal to the preset number;

[0022] Based on the polynomial curve fitting function, a one-dimensional profile is fitted according to the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction.

[0023] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein the preset calculation formula includes:

[0024]

[0025]

[0026]

[0027] in, , , Indicates the fitted value, Indicates the beamwidth value. This indicates the beam center value, and 'a' indicates the range direction, elevation direction, or azimuth direction. This indicates the maximum amplitude of the azimuth direction.

[0028] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein the preset Gaussian surface fitting algorithm includes:

[0029]

[0030] in, A two-dimensional array representing the maximum amplitude of azimuth and pitch directions; Indicates the maximum amplitude of the directional direction; The beam center value indicates the azimuth direction; The beamwidth value indicates the azimuth direction; The beam center value indicates the pitch direction; This indicates the beamwidth value in the pitch direction.

[0031] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein the step of correcting the transmission gap based on the two-dimensional array of the maximum amplitudes in the azimuth and pitch directions to obtain a one-dimensional array of the maximum amplitudes in the azimuth and pitch directions includes:

[0032] Traverse all elevation layers of the target sampling point, perform one-dimensional profile fitting based on the maximum intensity value in the azimuth direction, calculate the beamwidth, beam center value, and maximum amplitude value in the azimuth direction respectively, and divide them into two groups according to the odd or even number of elevation layers, and perform forward and reverse calculations respectively to obtain the beam center change value in the azimuth direction.

[0033] Based on the beam center change value, the two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions is corrected for transmission gaps to obtain a one-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

[0034] As described above and in any possible implementation, a further implementation is provided in which, before calculating the average value of the beamwidth value and the beamcenter value in the distance direction within the preset maximum amplitude range, the method further includes:

[0035] A two-dimensional array is constructed based on the beamwidth, beam center value, and maximum amplitude of the azimuth and elevation angles in the range direction.

[0036] According to a second aspect of this disclosure, a weather radar calibration device is provided. The device includes:

[0037] The acquisition module is used to acquire the maximum intensity value in the distance direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction of the target sampling point;

[0038] The fitting module is used to perform one-dimensional profile fitting based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction.

[0039] The calculation module is used to calculate the beamwidth and beam center value in the range direction, the beamwidth and beam center value in the pitch direction, the beamwidth and beam center value in the azimuth direction, and the maximum amplitude value, respectively, based on the preset calculation formula and according to the fitted values ​​in the range direction, the azimuth direction, and the pitch direction.

[0040] The calculation module is also used to calculate the average value of the beamwidth and beamcenter values ​​in the range direction within the preset maximum amplitude range, so as to obtain the beamwidth and beamcenter results in the range direction.

[0041] The fitting module is also used to perform Gaussian surface fitting based on a preset Gaussian surface fitting algorithm, according to the beamwidth and beam center values ​​in the pitch direction, the beamwidth and beam center values ​​in the azimuth direction, and the maximum amplitude value, to obtain a two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

[0042] The correction module is used to correct the transmission gap based on the two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions, and to obtain a one-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

[0043] The fitting module is also used to perform Gaussian surface fitting based on the one-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions, to obtain the beamwidth and beam center results in the pitch direction, the beamwidth and beam center results in the azimuth direction, and the maximum amplitude results.

[0044] The calculation module is also used to calculate the actual maximum amplitude based on the beamwidth and beam center results in the distance direction, the beamwidth and beam center results in the pitch direction, the beamwidth and beam center results in the azimuth direction, and the maximum amplitude result.

[0045] According to a third aspect of this disclosure, an electronic device is provided. The electronic device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the program to implement the method described above.

[0046] According to a fourth aspect of this disclosure, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the method described above.

[0047] This application provides a weather radar calibration method that can perform one-dimensional profile fitting on the maximum intensity values ​​in the range, azimuth, and elevation directions of the acquired target sampling points to obtain range, azimuth, and elevation fitted values. Then, based on a preset calculation formula, it calculates the beamwidth and beamcenter values ​​in the range, elevation, azimuth, and elevation directions, respectively, along with the maximum amplitude. It then calculates the average value of the range beamwidth and beamcenter values ​​within a preset maximum amplitude range to obtain the range beamwidth and beamcenter results. Finally, it performs parabolic fitting on the range to obtain the maximum amplitude on the range profile. Finally, based on a preset Gaussian surface fitting algorithm, it calculates the beamwidth and beamcenter values ​​in the elevation, azimuth, and elevation directions, respectively. Gaussian surface fitting is performed on the beamwidth, beamcenter, and maximum amplitude values ​​to obtain a two-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions. Then, transmission gap correction is performed based on this two-dimensional array to obtain a one-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions. Gaussian surface fitting is then performed on this one-dimensional array to obtain beamwidth and beamcenter results in the pitch direction, and beamwidth, beamcenter, and maximum amplitude results in the azimuth direction. Thus, two-dimensional surface fitting is performed using the maximum amplitude values ​​for different azimuth and pitch directions. Finally, based on the beamwidth and beamcenter results in the range direction, the beamwidth and beamcenter results in the pitch direction, and the beamwidth, beamcenter, and maximum amplitude results in the azimuth direction, the actual maximum amplitude value is calculated, thereby ultimately determining the actual maximum amplitude value corresponding to the metal sphere, significantly improving the accuracy and practicality of the metal sphere calibration.

[0048] It should be understood that the description in the Summary of the Invention is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0049] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. The drawings are provided for a better understanding of the invention and are not intended to limit the scope of this disclosure. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0050] Figure 1 A flowchart of a weather radar calibration method according to an embodiment of the present disclosure is shown;

[0051] Figure 2A schematic diagram of Gaussian surface fitting based on an embodiment of the present disclosure is shown;

[0052] Figure 3 A flowchart of another weather radar calibration method according to an embodiment of the present disclosure is shown;

[0053] Figure 4 A block diagram of a weather radar calibration apparatus according to an embodiment of the present disclosure is shown;

[0054] Figure 5 A block diagram of an exemplary electronic device capable of implementing embodiments of the present disclosure is shown. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0056] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0057] In this disclosure, the distance is first fitted with a parabola to obtain the maximum amplitude on the distance profile. Then, the maximum amplitude values ​​of different orientations and pitches are used to perform two-dimensional surface fitting, and finally the actual maximum amplitude value corresponding to the metal ball is determined, thereby significantly improving the accuracy and practicality of metal ball calibration.

[0058] Figure 1 A flowchart of a weather radar calibration method 100 according to an embodiment of the present disclosure is shown.

[0059] In box 110, obtain the maximum intensity value in the distance direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction of the target sampling point.

[0060] In some embodiments, the selection of target sampling points is determined based on the user's actual needs and a preset maximum intensity value range. The preset maximum intensity value range can be set to a range of -6dB to the left and right of the maximum intensity value.

[0061] For example, the maximum intensity value of the range direction sampling point measured in the radar data can be read first, and its location can be recorded. Then, all intensity values ​​within a range of -6dB to the left and right of the maximum intensity value can be extracted to determine the number of sampling points extracted. The extracted sampling points can be used as target sampling points to obtain the maximum intensity value of the range direction, the maximum intensity value of the azimuth direction, and the maximum intensity value of the pitch direction of the target sampling points, thus completing the selection before fitting the one-dimensional profile in the range, azimuth, and pitch directions.

[0062] In box 120, a one-dimensional profile is fitted based on the maximum intensity values ​​in the range direction, azimuth direction, and pitch direction to obtain the fitted values ​​in the range direction, azimuth direction, and pitch direction.

[0063] In some embodiments, when the number of target sampling points is greater than or equal to a preset number;

[0064] The above-mentioned one-dimensional profile fitting is performed based on the maximum intensity values ​​in the range direction, azimuth direction, and pitch direction to obtain the fitted values ​​in the range direction, azimuth direction, and pitch direction, specifically including:

[0065] Based on the polynomial curve fitting function, a one-dimensional profile is fitted according to the maximum intensity values ​​in the range direction, azimuth direction, and pitch direction to obtain the fitted values ​​in the range direction, azimuth direction, and pitch direction.

[0066] In some embodiments, when the number of target sampling points is less than a preset number;

[0067] The above-mentioned one-dimensional profile fitting is performed based on the maximum intensity values ​​in the range direction, azimuth direction, and pitch direction to obtain the fitted values ​​in the range direction, azimuth direction, and pitch direction, specifically including:

[0068] Obtain the sampling points in the distance library preceding and / or following the distance library containing the maximum intensity value in the distance direction of the target sampling point, and also use them as target sampling points, so that the number of target sampling points within the preset range is greater than or equal to the preset number;

[0069] Based on the polynomial curve fitting function, a one-dimensional profile is fitted according to the maximum intensity values ​​in the range direction, azimuth direction, and pitch direction to obtain the fitted values ​​in the range direction, azimuth direction, and pitch direction.

[0070] In some embodiments, the preset number can be set according to the user's actual needs, for example, the preset number can be set to 3.

[0071] In some embodiments, before fitting a one-dimensional profile for distance, azimuth, and pitch, the number of target sampling points needs to be determined to ensure sufficient data to guarantee the accuracy and practicality of the metal sphere calibration.

[0072] In some embodiments, when the number of target sampling points is greater than or equal to 3, a univariate quadratic function fitting can be performed directly, that is, a one-dimensional profile fitting can be performed directly based on the maximum intensity value in the distance direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction.

[0073] In some embodiments, when the number of target sampling points is less than 3, it is necessary to obtain the sampling points of the previous and / or next distance databases of the distance database containing the maximum intensity value of the target sampling point in the distance direction, and also use them as target sampling points, so that the number of target sampling points is greater than or equal to 3.

[0074] For example, if there is only one target sampling point, it is necessary to obtain the sampling points of the distance library before and after the distance library where the maximum intensity value of the target sampling point is located, and use them as target sampling points as well, so that the number of target sampling points is equal to 3.

[0075] For example, if there are two target sampling points, it is necessary to obtain the sampling points of the previous or next distance library of the distance library where the maximum intensity value of the target sampling point is located, or the sampling points of the previous and next distance libraries, and also use them as target sampling points, so that the number of target sampling points is greater than or equal to three.

[0076] In some embodiments, the polynomial curve fitting function may be the polyfit polynomial curve fitting function.

[0077] In some embodiments, the polyfit polynomial curve fitting function can be used to fit a quadratic function based on the maximum intensity value to obtain the fitted value, the expression of which is:

[0078]

[0079] in, For the maximum strength value, , , These are the polynomial coefficients, i.e., the fitted values, obtained through data fitting. 'a' represents the distance direction R and the pitch direction. Or direction .

[0080] In some embodiments, the above method can be used to fit the range direction, azimuth direction, and pitch direction, that is, to fit a quadratic function based on the maximum intensity value in the range direction to obtain the range direction fitted value; to fit a quadratic function based on the maximum intensity value in the azimuth direction to obtain the azimuth direction fitted value; and to fit a quadratic function based on the maximum intensity value in the pitch direction to obtain the pitch direction fitted value.

[0081] In box 130, based on the preset calculation formula, according to the fitted values ​​in the range direction, azimuth direction, and pitch direction, the beamwidth and beam center values ​​in the range direction, the beamwidth and beam center values ​​in the pitch direction, the beamwidth and beam center values ​​in the azimuth direction, and the maximum amplitude value are calculated respectively.

[0082] In some embodiments, the preset calculation formula can be set according to the user's actual needs.

[0083] In some embodiments, the above-mentioned preset calculation formula may include:

[0084]

[0085]

[0086]

[0087] in, , , The fitted value is obtained by fitting a quadratic function using the polyfit polynomial curve fitting function, based on the maximum intensity value. Indicates the beamwidth value. This indicates the beam center value, and 'a' represents the range direction R and elevation direction. Or direction ; This indicates the maximum amplitude of the azimuth direction.

[0088] Specifically, based on a preset calculation formula, the beamwidth and beamcenter values ​​in the range direction are calculated according to the fitted values ​​in the range direction, which may include:

[0089]

[0090]

[0091] in, , This represents the fitted value in the distance direction. This indicates the beamwidth value in the range direction. This indicates the beam center value in the distance direction.

[0092] Based on a preset calculation formula, calculating the beamwidth and beamcenter values ​​in the pitch direction using fitted values ​​can include:

[0093]

[0094]

[0095] in, , This represents the fitted value in the pitch direction. This indicates the beamwidth value in the pitch direction. This indicates the beam center value in the pitch direction.

[0096] Based on a preset calculation formula, the beamwidth, beam center value, and maximum amplitude in the azimuth direction are calculated according to the fitted values ​​of the azimuth direction, which may include:

[0097]

[0098]

[0099]

[0100] in, , , This represents the fitted value for the azimuth direction. This indicates the azimuth beamwidth value. Indicates the azimuth direction beam center value. This indicates the maximum amplitude of the azimuth direction.

[0101] In box 140, calculate the average value of the beamwidth and beamcenter values ​​in the range direction within the preset maximum amplitude range to obtain the beamwidth and beamcenter results in the range direction.

[0102] In some embodiments, the preset maximum amplitude range can be set according to the user's actual needs. For example, the preset maximum amplitude range can be set to the maximum amplitude value within -3dB.

[0103] In some embodiments, beamwidth and beamcenter values ​​in the range direction within a range of -3dB from the maximum amplitude value can be selected, and their average values ​​can be calculated to obtain... and The measurements of the target's center distance and radar pulse width are the beamwidth and beam center results in the range direction.

[0104] In box 150, based on the preset Gaussian surface fitting algorithm, Gaussian surface fitting is performed according to the beamwidth and beam center values ​​in the pitch direction, the beamwidth and beam center values ​​in the azimuth direction, and the maximum amplitude value to obtain a two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

[0105] like Figure 2 As shown, the maximum amplitude of the position and pitch directions can be fitted using a Gaussian surface function.

[0106] In some embodiments, the above-mentioned preset Gaussian surface fitting algorithm includes:

[0107]

[0108] in, A two-dimensional array representing the maximum amplitude of azimuth and pitch directions; Indicates the maximum amplitude of the directional direction; The beam center value indicates the azimuth direction; The beamwidth value indicates the azimuth direction; The beam center value indicates the pitch direction; This indicates the beamwidth value in the pitch direction.

[0109] In box 160, the transmission gap is corrected based on the two-dimensional array of the maximum amplitude in the azimuth and pitch directions, resulting in a one-dimensional array of the maximum amplitude in the azimuth and pitch directions.

[0110] In some embodiments, to further improve the accuracy and practicality of metal ball calibration, the orientation deviation caused by transmission gaps can be corrected.

[0111] In some embodiments, the transmission gap correction based on the two-dimensional array of maximum amplitudes in the azimuth and pitch directions, resulting in a one-dimensional array of maximum amplitudes in the azimuth and pitch directions, specifically includes:

[0112] Traverse all elevation layers of the target sampling point, perform one-dimensional profile fitting based on the maximum intensity value in the azimuth direction, calculate the beamwidth, beam center value, and maximum amplitude value in the azimuth direction respectively, and divide them into two groups according to the odd or even number of elevation layers, and perform forward and reverse calculations respectively to obtain the beam center change value in the azimuth direction.

[0113] Based on the beam center change value, a transmission gap correction is performed on the two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions to obtain a one-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

[0114] Specifically, first, all elevation angle layers are traversed, and the above-mentioned polynomial curve fitting function is used to fit the directional direction with a quadratic function. The calculated beamwidth, beam center, and maximum amplitude are then placed into two arrays according to whether the elevation angle layer number is odd or even.

[0115] Then, the array is rotated clockwise and counterclockwise to calculate and record the changes in the azimuth beam center. The calculation formula is as follows:

[0116]

[0117] In the formula, This represents the change in the beam center in the azimuth direction. The average value of the beam centers in the odd elevation angle layer. It represents the average value of the beam centers at even elevation angles.

[0118] For ease of calculation, the values ​​within the -6dB range of the maximum amplitude values ​​in the azimuth and pitch directions obtained above can be recorded in a one-dimensional array. Then, based on the change in the azimuth beam center, the azimuth deviation caused by transmission gaps in the array is corrected. The calculation formula is as follows:

[0119]

[0120] In the formula, These are the azimuth coordinates. These are the corrected azimuth coordinates.

[0121] In box 170, Gaussian surface fitting is performed based on the one-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions to obtain the beamwidth and beam center results in the pitch direction, the beamwidth and beam center results in the azimuth direction, and the maximum amplitude results.

[0122] In some embodiments,

[0123] After correcting for the positional deviation, the one-dimensional array is refitted using a pre-defined Gaussian surface fitting algorithm to obtain the corrected two-dimensional array. By outputting the fitting results of the two-dimensional array, the corrected maximum amplitude can be obtained. Azimuth direction beam center azimuth beamwidth Pitch direction beam center Pitch beamwidth That is, the beamwidth and beamcenter results in the pitch direction, the beamwidth and beamcenter results in the azimuth direction, and the maximum amplitude result, plus the range beamcenter obtained above. and range direction beamwidth By taking the beamwidth and beamcenter results in the range direction, the final maximum amplitude value can be calculated.

[0124] In box 180, the actual maximum amplitude is calculated based on the beamwidth and beam center results in the range direction, the beamwidth and beam center results in the pitch direction, the beamwidth and beam center results in the azimuth direction, and the maximum amplitude result.

[0125] like Figure 3 As shown, based on the flexible fitting method described above, information can be extracted from surrounding distance points for fitting, thereby ensuring accurate maximum amplitude data and guaranteeing the reliability and validity of the calculation results. It is evident that through the above process, even if the metal sphere is not precisely located at the center of the distance library, its corresponding actual maximum amplitude value can still be calculated.

[0126] According to the embodiments of this disclosure, the following technical effects are achieved:

[0127] It can perform one-dimensional profile fitting on the maximum intensity values ​​in the range, azimuth, and pitch directions of the acquired target sampling points to obtain range, azimuth, and pitch fitted values. Then, based on preset calculation formulas, it calculates the beamwidth and beamcenter values ​​in the range, pitch, azimuth, and pitch directions, respectively, along with the maximum amplitude. It then calculates the average of the range beamwidth and beamcenter values ​​within a preset maximum amplitude range to obtain the range beamwidth and beamcenter results. This completes parabolic fitting of the range profile, yielding the maximum amplitude value. Finally, based on a preset Gaussian surface fitting algorithm, it calculates the beamwidth and beamcenter values ​​in the pitch, azimuth, and pitch directions, respectively. Gaussian surface fitting is performed on the center value and maximum amplitude to obtain a two-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions. Then, transmission gap correction is performed based on the two-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions to obtain a one-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions. Gaussian surface fitting is then performed on the one-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions to obtain the beamwidth and beamcenter results in the pitch direction, the beamwidth and beamcenter results in the azimuth direction, and the maximum amplitude results. Thus, two-dimensional surface fitting is performed using the maximum amplitude values ​​in different azimuth and pitch directions. Finally, based on the beamwidth and beamcenter results in the range direction, the beamwidth and beamcenter results in the pitch direction, the beamwidth and beamcenter results in the azimuth direction, and the maximum amplitude results, the actual maximum amplitude value is calculated, thereby finally determining the actual maximum amplitude value corresponding to the metal sphere, which significantly improves the accuracy and practicality of the metal sphere calibration.

[0128] In some embodiments, before calculating the average value of the beamwidth and beamcenter values ​​in the distance direction within the preset maximum amplitude range, the method further includes:

[0129] A two-dimensional array is constructed based on the beamwidth, beam center value, and maximum amplitude of the azimuth and elevation angles in the range direction.

[0130] In some embodiments, to facilitate subsequent selection and calculation, a two-dimensional array can be constructed to record the beamwidth, beam center value, and maximum amplitude value in the range direction for different azimuth and elevation angles.

[0131] In summary, this disclosure can be applied to radar metal ball calibration experiments, overcoming the current problem of needing to control the continuous movement of the suspended metal ball by the UAV, and eliminating the need to ensure that the metal ball is in the center of the radar beam and range gauge. This improvement reduces the operational difficulty of the metal ball calibration experiment and improves the efficiency of the experiment.

[0132] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this disclosure is not limited to the described order of actions, because according to this disclosure, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this disclosure.

[0133] The above is an introduction to the method embodiments. The following describes the solution described in this disclosure further through device embodiments.

[0134] Figure 4 A block diagram of a weather radar calibration device 400 according to an embodiment of the present disclosure is shown. Figure 4 As shown, the device 400 includes:

[0135] The acquisition module 410 is used to acquire the maximum intensity value in the distance direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction of the target sampling point.

[0136] The fitting module 420 is used to perform one-dimensional profile fitting based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction, to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction.

[0137] The calculation module 430 is used to calculate the beamwidth and beam center value in the range direction, the beamwidth and beam center value in the pitch direction, the beamwidth and beam center value in the azimuth direction, and the maximum amplitude value, respectively, based on the preset calculation formula and the fitted values ​​in the range direction, azimuth direction, and pitch direction.

[0138] The calculation module 430 is also used to calculate the average value of the beamwidth and beamcenter values ​​in the range direction within the preset maximum amplitude range, so as to obtain the beamwidth and beamcenter results in the range direction.

[0139] The fitting module 420 is also used to perform Gaussian surface fitting based on a preset Gaussian surface fitting algorithm, according to the beamwidth and beam center values ​​in the pitch direction, the beamwidth and beam center values ​​in the azimuth direction, and the maximum amplitude value, to obtain a two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

[0140] Correction module 440 is used to correct transmission gaps based on a two-dimensional array of maximum amplitude values ​​in azimuth and pitch directions, and to obtain a one-dimensional array of maximum amplitude values ​​in azimuth and pitch directions.

[0141] The fitting module 420 is also used as a module to perform Gaussian surface fitting based on a one-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions, to obtain beamwidth and beam center results in the pitch direction, beamwidth and beam center results in the azimuth direction, and maximum amplitude results.

[0142] The calculation module 430 is also used to calculate the actual maximum amplitude based on the beamwidth and beam center results in the range direction, the beamwidth and beam center results in the elevation direction, the beamwidth and beam center results in the azimuth direction, and the maximum amplitude result.

[0143] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the described module can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0144] The acquisition, storage, and application of user personal information involved in the technical solution disclosed herein comply with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0145] According to embodiments of this disclosure, this disclosure also provides an electronic device, a readable storage medium, and a computer program product.

[0146] Figure 5 A block diagram of an exemplary electronic device 500 capable of implementing embodiments of the present disclosure is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0147] Electronic device 500 includes a computing unit 501, which can perform various appropriate actions and processes according to a computer program stored in ROM 502 or a computer program loaded into RAM 503 from storage unit 508. RAM 503 can also store various programs and data required for the operation of electronic device 500. The computing unit 501, ROM 502, and RAM 503 are interconnected via bus 504. I / O interface 505 is also connected to bus 504.

[0148] Multiple components in electronic device 500 are connected to I / O interface 505, including: input unit 506, such as keyboard, mouse, etc.; output unit 507, such as various types of monitors, speakers, etc.; storage unit 508, such as disk, optical disk, etc.; and communication unit 509, such as network card, modem, wireless transceiver, etc. Communication unit 509 allows electronic device 500 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0149] Computing unit 501 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of computing unit 501 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Computing unit 501 performs the various methods and processes described above, such as method 100. For example, in some embodiments, method 100 may be implemented as a computer software program tangibly contained in a machine-readable medium, such as storage unit 508.

[0150] In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 500 via ROM 502 and / or communication unit 509. When the computer program is loaded into RAM 503 and executed by computing unit 501, one or more steps of method 100 described above may be performed. Alternatively, in other embodiments, computing unit 501 may be configured to perform method 100 by any other suitable means (e.g., by means of firmware).

[0151] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0152] The program code used to implement the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0153] In the context of this disclosure, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0154] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including voice input, speech input, or tactile input).

[0155] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as a data server), or computing systems that include middleware components (e.g., an application server), or computing systems that include frontend components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., a communication network). Examples of communication networks include local area networks (LANs), wide area networks (WANs), and the Internet.

[0156] Computer systems can include clients and servers. Clients and servers are generally located far apart and typically interact via communication networks. Client-server relationships are created by computer programs running on the respective computers and having a client-server relationship with each other. Servers can be cloud servers, servers in distributed systems, or servers incorporating blockchain technology.

[0157] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this disclosure can be achieved, and this is not limited herein.

[0158] The specific embodiments described above do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A weather radar calibration method, characterized in that, include: Obtain the maximum intensity value in the distance direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction of the target sampling point; One-dimensional profile fitting is performed based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction. Based on the preset calculation formula, according to the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction, the beamwidth and beam center values ​​in the range direction, the beamwidth and beam center values ​​in the pitch direction, the beamwidth, beam center value, and maximum amplitude value in the azimuth direction are calculated respectively. Calculate the average value of the beamwidth and beamcenter in the range of the preset maximum amplitude value to obtain the beamwidth and beamcenter results in the range direction. Based on a preset Gaussian surface fitting algorithm, Gaussian surface fitting is performed according to the beamwidth and beam center values ​​in the pitch direction, the beamwidth and beam center values ​​in the azimuth direction, and the maximum amplitude value to obtain a two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions. Based on the two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions, the transmission gap is corrected to obtain a one-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions. Gaussian surface fitting is performed based on the one-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions to obtain the beamwidth and beam center results in the pitch direction, the beamwidth and beam center results in the azimuth direction, and the maximum amplitude results. The actual maximum amplitude is calculated based on the beamwidth and beamcenter results in the range direction, the beamwidth and beamcenter results in the pitch direction, the beamwidth and beamcenter results in the azimuth direction, and the maximum amplitude result.

2. The method according to claim 1, characterized in that, When the number of target sampling points is greater than or equal to the preset number; The step of performing one-dimensional profile fitting based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the range direction fitted value, the azimuth direction fitted value, and the pitch direction fitted value includes: Based on the polynomial curve fitting function, a one-dimensional profile is fitted according to the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction.

3. The method according to claim 2, characterized in that, When the number of target sampling points is less than the preset number; The step of performing one-dimensional profile fitting based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the range direction fitted value, the azimuth direction fitted value, and the pitch direction fitted value includes: Obtain the sampling points in the distance library preceding and / or following the distance library containing the maximum intensity value in the distance direction of the target sampling point, and also use them as target sampling points, so that the number of target sampling points is greater than or equal to the preset number; Based on the polynomial curve fitting function, a one-dimensional profile is fitted according to the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction.

4. The method according to claim 1, characterized in that, The preset calculation formula includes: in, , , Indicates the fitted value, Indicates the beamwidth value. This indicates the beam center value, and 'a' indicates the range direction, elevation direction, or azimuth direction. This indicates the maximum amplitude of the azimuth direction.

5. The method according to claim 1, characterized in that, The preset Gaussian surface fitting algorithm includes: in, Indicates the maximum amplitude of azimuth and pitch directions; Indicates the maximum amplitude of the directional direction; The beam center value indicates the azimuth direction; The beamwidth value indicates the azimuth direction; The beam center value indicates the pitch direction; This indicates the beamwidth value in the pitch direction.

6. The method according to claim 1, characterized in that, The process of correcting transmission gaps based on the two-dimensional array of maximum amplitudes in the azimuth and pitch directions to obtain a one-dimensional array of maximum amplitudes in the azimuth and pitch directions includes: Traverse all elevation layers of the target sampling point, perform one-dimensional profile fitting based on the maximum intensity value in the azimuth direction, calculate the beamwidth, beam center value, and maximum amplitude value in the azimuth direction respectively, and divide them into two groups according to the odd or even number of elevation layers, and perform forward and reverse calculations respectively to obtain the beam center change value in the azimuth direction. Based on the beam center change value, the two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions is corrected for transmission gaps to obtain a one-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions.

7. The method according to any one of claims 1 to 6, characterized in that, Before calculating the average value of the beamwidth and beamcenter values ​​in the distance direction within the preset maximum amplitude range, the method further includes: A two-dimensional array is constructed based on the beamwidth, beam center value, and maximum amplitude of the azimuth and elevation angles in the range direction.

8. A weather radar calibration device, characterized in that, include: The acquisition module is used to acquire the maximum intensity value in the distance direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction of the target sampling point; The fitting module is used to perform one-dimensional profile fitting based on the maximum intensity value in the range direction, the maximum intensity value in the azimuth direction, and the maximum intensity value in the pitch direction to obtain the fitted values ​​in the range direction, the fitted values ​​in the azimuth direction, and the fitted values ​​in the pitch direction. The calculation module is used to calculate the beamwidth and beam center value in the range direction, the beamwidth and beam center value in the pitch direction, the beamwidth and beam center value in the azimuth direction, and the maximum amplitude value, respectively, based on the preset calculation formula and according to the fitted values ​​in the range direction, the azimuth direction, and the pitch direction. The calculation module is also used to calculate the average value of the beamwidth and beamcenter values ​​in the range direction within the preset maximum amplitude range, so as to obtain the beamwidth and beamcenter results in the range direction. The fitting module is also used to perform Gaussian surface fitting based on a preset Gaussian surface fitting algorithm, according to the beamwidth and beam center values ​​in the pitch direction, the beamwidth and beam center values ​​in the azimuth direction, and the maximum amplitude value, to obtain a two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions. The correction module is used to correct the transmission gap based on the two-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions, and to obtain a one-dimensional array of the maximum amplitude values ​​in the azimuth and pitch directions. The fitting module is also used to perform Gaussian surface fitting based on the one-dimensional array of maximum amplitude values ​​in the azimuth and pitch directions to obtain beamwidth and beam center results in the pitch direction, beamwidth and beam center results in the azimuth direction, and maximum amplitude results. The calculation module is also used to calculate the actual maximum amplitude based on the beamwidth and beam center results in the distance direction, the beamwidth and beam center results in the pitch direction, the beamwidth and beam center results in the azimuth direction, and the maximum amplitude result.

9. An electronic device, characterized in that, include: At least one processor; as well as A memory that is communicatively connected to the at least one processor; The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to cause the computer to perform the method according to any one of claims 1-7.

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