An error compensation method and system for rain-measuring radar antenna calibration

Abstract

This invention relates to the field of antenna calibration technology, and specifically to a method and system for error compensation in the calibration of rain-measuring radar antennas. The method includes: acquiring antenna module interface displacement data, antenna thermal cycling recording data, and calibration reference source response data; performing structural memory effect error assessment based on the antenna module interface displacement data and the antenna thermal cycling recording data; performing electrical performance error assessment based on the calibration reference source response data; performing coupling error matching analysis to obtain a comprehensive calibration error matching value; and providing calibration status prompts based on the comprehensive calibration error matching value. This invention solves the problem of calibration benchmark inaccuracy caused by the coupling of disassembly / reassembly history and thermal memory effect in portable rain-measuring radars in the prior art.

Description

Technical Field

[0001] This invention relates to the field of antenna calibration technology, and is a method and system for error compensation in the calibration of rain measuring radar antennas. Background Technology

[0002] Weather radar is a core device for monitoring precipitation and issuing early warnings of severe convective weather. Among them, X-band dual-polarization portable radar is widely used in emergency meteorological support and flash flood warning due to its high mobility and flexible deployment. These radars usually adopt a modular design, including antenna units, transceiver side boxes, turntables and tripods, which can be quickly assembled on site. However, this portability also brings unique technical challenges to the calibration process.

[0003] Currently, most radar calibration focuses on correcting the static parameters of fixed radars, such as using metal spheres for far-field calibration and solar normal radiation calibration. These methods can compensate for the fixed errors of the antenna system to some extent, but they ignore the problems of portable radars: First, the interface wear and reference offset caused by repeated modular disassembly and assembly. The antenna unit is connected to the side box and elevation box via quick connectors. After repeated disassembly and assembly, the micron-level wear of the connection surface and the inconsistency of the tightening torque will cause random distortion of the antenna phase center and polarization reference. This distortion is often treated as a fixed system error in traditional calibration, but in reality, it is non-repeating after each assembly. Secondly, to meet portability requirements, the antenna waveguide cavity and support structure extensively use lightweight aluminum alloy and carbon fiber composite materials, which have low heat capacity and fast heat dissipation. When the radar continuously transmits at high power to measure rain, the T / R components arranged on one side generate an asymmetric thermal field, causing the back of the antenna to bear uneven thermal stress. After shutdown and cooling, due to the thermoelastic hysteresis effect of the material, the waveguide cavity still retains the quasi-static non-uniform deformation memory induced by thermal cycling. If calibration is performed using traditional methods, the obtained parameters are actually pseudo-references based on the unsteady residual deformation field. When the radar is restarted and heated up, the compensated parameters will introduce additional polarization measurement errors. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0005] The technical problem to be solved by this invention is the inaccuracy of the calibration reference caused by the coupling of disassembly and assembly history and thermal memory effect in portable rain measuring radars in the prior art. This invention proposes an error compensation method and system for the calibration of rain measuring radar antennas.

[0006] To achieve the above objectives, the technical solution of the error compensation method for rain-measuring radar antenna calibration of the present invention includes the following steps: Step S1: Obtain antenna module interface displacement data, antenna thermal cycling record data, and calibration reference source response data; Step S2: Based on the antenna module interface displacement data and the antenna thermal cycling recording data, perform structural memory effect error assessment to obtain the cumulative assessment value of azimuth interface offset and the cumulative assessment value of pitch interface offset. Step S3: Based on the calibration reference source response data, perform electrical performance error assessment to obtain the electrical performance error assessment value of the horizontal polarization channel and the comprehensive performance error assessment value of the vertical polarization channel; Step S4: Perform coupling error matching analysis using the cumulative evaluation value of the azimuth interface offset, the cumulative evaluation value of the pitch interface offset, the electrical performance error evaluation value of the horizontal polarization channel, and the comprehensive performance error evaluation value of the vertical polarization channel to obtain the comprehensive calibration error matching value. Step S5: Provide a calibration status prompt based on the comprehensive calibration error matching value.

[0007] Preferably, the structural memory effect error assessment includes the following specific steps: Obtain the initial displacement value of the laser displacement sensor located at the antenna module connection flange after each assembly, as well as the thermal stress distribution cloud map on the back of the antenna; Using the thermal stress distribution cloud map on the back of the antenna as a boundary condition, the data is input into the pre-constructed contact stress recovery model of the connection interface between the antenna and the turntable to obtain the flange displacement vector relative to the antenna azimuth axis and the flange displacement vector relative to the pitch axis. Based on the flange displacement vector of the antenna relative to the azimuth axis and the degree of offset of the actual centroid position of the antenna module relative to the designed centroid position, an azimuth interface offset accumulation analysis is performed. The azimuth interface offset accumulation analysis process is as follows: the length of the overlapping segment of the antenna azimuth flange displacement vector after two adjacent disassembly and assembly cycles is obtained and divided by the total envelope length of the antenna azimuth flange displacement vector after the corresponding two disassembly and assembly cycles to obtain the displacement retention rate between the corresponding two disassembly and assembly cycles. The displacement change rate is obtained by subtracting the displacement retention rate from 1. The displacement change rate is accumulated over each disassembly and assembly cycle to obtain the total azimuth offset accumulation of the corresponding antenna. The degree of deviation of the actual centroid position relative to the designed centroid position is obtained by measuring the antenna attitude change values ​​before and after disassembly using multiple high-precision tilt gauges arranged on the antenna module, combined with the three-dimensional model of the antenna module to calculate the centroid position. The projection component of the vector offset of the actual centroid relative to the designed centroid on the azimuth axis is divided by the preset reference length to obtain the azimuth centroid offset coefficient. The cumulative evaluation value of the azimuth interface offset of the corresponding antenna is obtained by multiplying the cumulative total azimuth offset of the corresponding antenna with the azimuth centroid offset coefficient. Based on the flange displacement vector of the antenna relative to the pitch axis and the degree of offset of the actual centroid position of the antenna module relative to the designed centroid position, the pitch interface offset cumulative analysis is performed. The calculation method is the same as that of the azimuth direction, and the pitch interface offset cumulative evaluation value is obtained.

[0008] Preferably, the electrical performance error assessment includes the following specific steps: In calibration mode, the cross-polarization isolation time sequence, main lobe broadening coefficient and side lobe level rise of the antenna are extracted synchronously. At the same time, the surface temperature distribution cloud map is obtained by the thermocouple array buried on the back of the waveguide cavity, and the change in waveguide cavity wall thickness is recorded by laser thickness gauge. For the horizontally polarized channel, the main lobe widening coefficient and the side lobe level rise are extracted based on the radiation pattern test results. The relative deviations of the two from the calibration reference values ​​are calculated respectively. The main lobe widening deviation coefficient and the side lobe rise deviation coefficient are weighted and summed to obtain the electrical performance error evaluation value of the horizontally polarized channel. For the vertical polarization channel, in addition to the main lobe broadening factor and the side lobe level rise, the cross-polarization isolation degradation is introduced as an evaluation dimension. At the same time, the waveguide cavity surface temperature distribution cloud map and the wall thickness change are input into the pre-constructed thermo-mechanical coupling deformation prediction model to perform thermo-mechanical coupling deformation analysis and obtain the comprehensive performance error evaluation value of the vertical polarization channel. The acquisition of the cross-polarization isolation degradation includes: based on the cross-polarization isolation time series, subtracting the cross-polarization component contributed by the system noise floor to obtain the cross-polarization isolation degradation.

[0009] Preferably, the comprehensive performance error assessment of the vertical polarization channel specifically includes: Obtain the main lobe broadening coefficient and cross-polarization isolation degradation of the antenna's vertical polarization pattern, calculate the relative deviations of the two from the corresponding calibration reference values, and then weight and fuse the main lobe broadening deviation coefficient and the cross-polarization isolation degradation coefficient to obtain the basic electrical error assessment value of the vertical polarization channel. Meanwhile, based on the surface temperature distribution cloud map of the waveguide cavity, the known thermal expansion coefficient of the waveguide material, and the wall thickness change recorded by the laser thickness gauge, the residual deformation of the waveguide cavity under the current thermal history conditions is inferred through the thermo-mechanical coupling deformation prediction model. The construction of the thermo-mechanical coupling deformation prediction model includes, but is not limited to, the experimental calibration model construction method and the deep learning network model construction method; The ratio of the deduced residual deformation to the safe deformation of the waveguide cavity is used as the thermo-mechanical coupling deformation error coefficient. This coefficient is then weighted and fused with the basic electrical error assessment value of the vertical polarization channel to obtain the comprehensive performance error assessment value of the vertical polarization channel.

[0010] Preferably, the coupling error matching analysis includes the following specific contents: The cumulative evaluation values ​​of azimuth and pitch interface offsets obtained from the structural memory effect error assessment, and the comprehensive performance error evaluation values ​​of the horizontal polarization channel and the vertical polarization channel obtained from the electrical performance error assessment are obtained. The azimuth-horizontal coupling error is obtained by weighted summing of the cumulative evaluation value of the azimuth interface offset and the electrical performance error evaluation value of the horizontal polarization channel. The pitch-vertical coupling error is obtained by weighted summing of the cumulative evaluation value of the pitch interface offset and the comprehensive performance error evaluation value of the vertical polarization channel. The weighted sum of the two coupling errors is the comprehensive calibration error matching value.

[0011] Preferably, the generation of the calibration compensation coefficient includes the following specific steps: The comprehensive calibration error matching value is compared with the preset comprehensive error tolerance threshold: if the comprehensive calibration error matching value is less than the corresponding comprehensive error tolerance threshold, it is determined that the current calibration status meets the observation accuracy requirements, and a normal calibration status prompt is directly output, and the existing calibration parameters are used for subsequent rainfall measurement tasks; if the comprehensive calibration error matching value is greater than or equal to the corresponding comprehensive error tolerance threshold, the compensation coefficient generation process is entered. The compensation coefficient generation process specifically includes: First, based on the cumulative evaluation value of the azimuth interface offset and the cumulative evaluation value of the pitch interface offset obtained in step S2, and combined with the electrical performance error evaluation value of the horizontal polarization channel and the comprehensive performance error evaluation value of the vertical polarization channel obtained in step S3, the azimuth-horizontal coupling compensation factor and the pitch-vertical coupling compensation factor are constructed respectively. Among them, the azimuth-horizontal coupling compensation factor is calculated by the ratio of the cumulative evaluation value of the azimuth offset to the interface to the electrical performance error evaluation value of the horizontal polarization channel, and the pitch-vertical coupling compensation factor is calculated by the ratio of the cumulative evaluation value of the pitch offset to the interface to the comprehensive performance error evaluation value of the vertical polarization channel. Then, a 2×2 polarization compensation matrix is ​​constructed using the two compensation factors mentioned above as the main diagonal elements. This matrix is ​​used to correct the differential reflectivity factor and differential propagation phase shift measurement value of the dual polarization receiving channel in real time during subsequent rainfall measurement tasks. Finally, the generated compensation matrix is ​​written into the parameter memory of the radar signal processing unit, and a status prompt indicating that the calibration compensation is complete is output for the operator to confirm.

[0012] Preferably, the displacement data of the antenna module interface is collected by a laser displacement sensor arranged at the antenna connection flange after each disassembly and assembly and after each major thermal cycle cooling stabilization, and the micro-displacement time sequence of the flange contact surface is recorded. The antenna thermal cycling recording data is acquired in real time through a multi-point thermocouple array embedded in the contact surface between the back of the waveguide cavity and the side box, and the radar transmission power duration and corresponding temperature change curve are recorded synchronously. The calibration reference source response data includes: The echo intensity and polarization response values ​​obtained during metal sphere calibration are used to extract the main lobe broadening coefficient, side lobe level rise, and cross-polarization isolation time sequence of the radiation pattern; The polarization brightness temperature data of the sky background noise is used to calibrate the noise floor of the radar receiving system, and the cross-polarization component contributed by the noise floor is subtracted from the cross-polarization isolation time series to obtain the cross-polarization isolation degradation amount.

[0013] In addition, the error compensation system for the calibration of a rain-measuring radar antenna of the present invention includes the following modules: The data acquisition module acquires antenna module interface displacement data, antenna thermal cycling record data, and calibration reference source response data. The structural memory effect evaluation module evaluates the structural memory effect error based on the antenna module interface displacement data and the antenna thermal cycling record data, and obtains the cumulative evaluation value of the azimuth interface offset and the cumulative evaluation value of the pitch interface offset. The electrical performance evaluation module performs electrical performance error evaluation based on the calibration reference source response data to obtain the electrical performance error evaluation value of the horizontal polarization channel and the comprehensive performance error evaluation value of the vertical polarization channel. The matching analysis module performs coupled error matching analysis using the cumulative evaluation value of the azimuth interface offset, the cumulative evaluation value of the pitch interface offset, the electrical performance error evaluation value of the horizontal polarization channel, and the comprehensive performance error evaluation value of the vertical polarization channel to obtain a comprehensive calibration error matching value. The compensation module provides calibration status prompts based on the comprehensive calibration error matching value.

[0014] A storage medium storing instructions, wherein when a computer reads the instructions, the computer executes the aforementioned error compensation method for calibrating a rain-measuring radar antenna.

[0015] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the above-described error compensation method for calibrating a rain-measuring radar antenna.

[0016] Compared with the prior art, the technical effects of the present invention are as follows: 1. This invention addresses two long-neglected structural error sources in portable radar: interface micro-displacement wear accumulated from repeated modular disassembly and assembly, non-repeatable reference drift caused by inconsistent fastening torque, and quasi-static non-uniform deformation memory of waveguide cavity induced by unilateral thermal load cycles. By constructing two parallel analysis paths—structural memory effect assessment and electrical performance error assessment—and performing coupled matching analysis on the two, this invention solves the problem that existing technologies cannot distinguish the contribution of structural reference offset and electrical performance degradation. 2. This invention physically correlates and matches the cumulative evaluation values ​​of the interface offsets in the azimuth and elevation directions with the evaluation values ​​of the electrical performance errors of the horizontal and vertical polarization channels, respectively constructing azimuth-horizontal coupling compensation factors and elevation-vertical coupling compensation factors, and forming a polarization compensation matrix. This matrix can dynamically generate exclusive compensation parameters based on the actual structural state and thermal history state of the radar after each disassembly and reassembly, and correct the differential reflectivity factor and differential propagation phase shift measurement values ​​of the dual polarization receiving channels in real time during subsequent rain measurement missions. This effectively eliminates the polarization measurement errors introduced by the inconsistency of disassembly and reassembly references and the coupling of thermal memory effects, so that the portable rain measurement radar can still maintain polarization measurement accuracy equivalent to the factory calibration after undergoing disassembly and reassembly in the field or continuous high-power operation. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a flowchart illustrating an error compensation method for calibrating a rain-measuring radar antenna according to the present invention. Figure 2 This is a schematic diagram of the error compensation system for calibrating a rain-measuring radar antenna according to the present invention. Detailed Implementation

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0019] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0020] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0021] Example 1: like Figure 1 As shown in the figure, an error compensation method for the calibration of a rain-measuring radar antenna according to an embodiment of the present invention is as follows: Figure 1 As shown, the specific steps include the following: Step S1: Obtain antenna module interface displacement data, antenna thermal cycling record data, and calibration reference source response data; The displacement data of the antenna module interface is collected by a laser displacement sensor located at the antenna connection flange after each disassembly and assembly and after each major thermal cycle cooling and stabilization. The micro-displacement time sequence of the flange contact surface is recorded, and this sequence is used for the accumulation of displacement changes in step S2. The antenna thermal cycling recording data is acquired in real time through a multi-point thermocouple array embedded in the contact surface between the back of the waveguide cavity and the side box, and the radar transmission power duration and corresponding temperature change curve are recorded synchronously. This data is used as the input for the thermo-mechanical coupling deformation prediction model in step S3. The calibration reference source response data includes: The echo intensity and polarization response values ​​obtained during metal sphere calibration are used to extract the main lobe broadening coefficient, side lobe level rise, and cross-polarization isolation time sequence of the radiation pattern; This data is obtained by scanning a metal sphere with radar and recording the echo intensity of the horizontal and vertical polarization channels at different azimuth and elevation angles. Using the theoretical radar cross-section of the metal sphere as a reference, the echo intensity is calibrated to obtain the gain distribution of the main lobe and side lobe regions of the antenna pattern. The proportion of the main lobe peak gain decrease is extracted as the main lobe broadening factor, and the change in the ratio of the first side lobe gain to the main lobe peak gain is extracted as the side lobe level rise. Simultaneously, the cross-polarization isolation is obtained by calculating the ratio of the vertical polarization channel echo intensity to the horizontal polarization channel echo intensity at the same angle. The cross-polarization isolation time series is then generated by traversing the scanning angles. In another preferred embodiment, the antenna pattern main lobe broadening factor and side lobe level rise can also be obtained by solar normal radiation calibration, including: the antenna pointing error sequence obtained during solar normal radiation calibration, which is used to invert and calculate the current antenna pattern main lobe broadening factor and side lobe level rise; The pointing deviation component is formed by recording the deviation between the actual azimuth and elevation angles of the sun and the pointing angle of the radar antenna during the solar normal radiation calibration process. The systematic pointing deviation component is obtained by statistically averaging this deviation sequence. The pointing deviation component is used as input and substituted into the theoretical analytical expression of the antenna pattern or the electromagnetic simulation database. By changing the main lobe width parameter and the side lobe level parameter in the pattern analytical expression, the root mean square error between the reconstructed pattern envelope and the actual measured pattern envelope under the pointing deviation component is minimized. The corresponding main lobe width parameter and side lobe level parameter at this time are the main lobe broadening factor and side lobe level rise of the current antenna pattern. Specifically, in another preferred embodiment, a method is also provided for inverting and calculating the main lobe broadening factor and side lobe level rise of the current antenna pattern using the antenna pointing error sequence obtained during the solar normal radiation calibration process. This method does not require the additional construction of a complex near-field or far-field test environment and directly uses the radar's daily calibration data to complete the pattern distortion assessment.

[0022] First, select the antenna pattern analytical model, as follows: To simultaneously describe both main lobe widening and sidelobe level rise distortion features, this embodiment uses the following pattern function: ; in: The angle of deviation from the antenna's electrical axis; For the normalized power pattern, at the main lobe peak... ; The main lobe width factor is inversely proportional to the actual main lobe width of the antenna. It should be noted that for a uniform aperture rectangular antenna, the actual main lobe half-power width... , The smaller the value, the more severe the main lobe widening; For example, the sidelobe level rise amount, 0.1 indicates that the power in the sidelobe region is increased by 0.1 compared to the ideal value. It should be noted that the first sidelobe level of an ideal uniform aperture antenna is approximately 0.047. If the measured sidelobe level is 0.1, then... ; The side lobe initiation angle is usually taken as the theoretical zero point position or the peak position of the first side lobe. It should be noted that for an aperture size of [missing information], [missing information]. The working wavelength is The antenna can be selected first. (i.e., the first zero point) or (i.e., the position of the first sidelobe peak), the specific value of which can be preset according to the antenna design parameters; symbol The unit step function is defined as follows: ; Let be the singer function, where It should be noted that in this model Used to describe the radiation pattern shape of an ideal uniform aperture antenna, where the main lobe peak value is normalized to 1, and the side lobe level varies with... Increases and then naturally decreases, coefficient The angular axis is used for linear scaling, designed to simulate changes in the main lobe width; in this model... That is, in the side lobe region ( ) superimposed with a constant lift This study aims to simulate the overall rise in sidelobe level caused by antenna surface errors, structural deformation, etc. It should also be noted that this rise occurs in the main lobe region (…). The value is zero to ensure that the fitting of the main lobe shape is not interfered with.

[0023] In the data processing for solar normal radiation calibration, the known solar pointing deviation components are... Substituting the above pattern function, we calculate the curve of theoretical received power changing with pointing deviation. By adjusting the parameters... and This minimizes the root mean square error between the theoretical curve and the measured curve of solar radiation power received by the radar as a function of the pointing angle. and These are the main lobe width coefficient and the side lobe level rise, which are to be determined.

[0024] The main lobe expansion coefficient is defined as follows: ( (The ideal main lobe width coefficient is the factory-calibrated value), and the side lobe level rise is directly taken as... .

[0025] It should be noted that this model is applicable when the main lobe widening is not extreme ( (Not less than 70% of the ideal value) and the elevation of the accessory valve is relatively small ( In scenarios where the distortion is no greater than 0.2, if severe antenna distortion leads to complex features such as asymmetry or null filling in the radiation pattern, those skilled in the art can perform more precise matching by combining electromagnetic simulation databases. It should also be noted that the above model calculation in this embodiment is simple and easy to implement in real-time or near real-time in the radar signal processing unit.

[0026] Then, data acquisition and preprocessing are performed, including: during the solar normal radiation calibration process, the radar antenna scans the sun at fixed step sizes and records the azimuth pointing angle of each scan point. With the corresponding received power The step size is 0.05° to 0.1°, and the scanning range is -1.5° to +1.5°.

[0027] It should be noted that the sun can be regarded as an ideal point source, and its radiation intensity is considered constant during the calibration period.

[0028] Assume total collection 10 valid data points constitute the dataset Normalize the data: Find the maximum received power ; The power at each measurement point is normalized to .

[0029] Normalized data points This refers to the discrete sampled values ​​of the antenna pattern obtained from actual measurements.

[0030] Next, the objective function for parameter inversion is constructed, including minimizing the difference between the actual measured radiation pattern and the model radiation pattern, and constructing a least-squares objective function: ; in Calculate according to the aforementioned model formula.

[0031] The solution method employs the Levenberg-Marquardt numerical optimization algorithm, which is suitable for nonlinear least squares problems and has a fast convergence speed. The solution steps are as follows: Step X1: Set initial values ​​for iteration: That is, the theoretical main lobe width corresponds to value (where Antenna aperture, (for the operating wavelength) That is, assuming there is no sidelobe elevation at the initial moment.

[0032] Step X2: In the first In each iteration, the Jacobian matrix under the current parameters is calculated. and residual vector Then update the parameters: ; in, Indicates and Identity matrices of the same dimension This is the damping factor, which is dynamically adjusted according to changes in the residual.

[0033] Step X3: When the parameter change between two iterations is less than a preset threshold (e.g., ... If the objective function decreases by less than a threshold, the iteration stops.

[0034] Finally, the results are transformed, including: Let the optimal parameters obtained by convergence be... and Then: main lobe expansion coefficient Defined as the ratio of the actual main lobe width to the theoretical main lobe width, since the main lobe width and... Inversely proportional, therefore: ;in The theoretical main lobe width corresponds to value.

[0035] when The time indicates that the main lobe has widened. This indicates that the main lobe has narrowed.

[0036] Sidelobe level rise That is, the converged result. This indicates the linear increase in sidelobe gain relative to the theoretical direction, which can be directly used as a linear evaluation index of sidelobe level rise for subsequent error compensation calculations.

[0037] It should also be noted that this embodiment applies to conditions where the weather is clear, there are no cloud cover, and the solar altitude angle is greater than 15° during the solar normal radiation calibration period. After data acquisition, validity verification is required, including: calculating the symmetry of the radiation pattern of the acquired data. If the asymmetry of the power distribution on the left and right sides exceeds 20%, the data is deemed invalid and recalibrated.

[0038] The polarization brightness temperature data of the sky background noise is used to calibrate the noise floor of the radar receiving system, and the cross-polarization component contributed by the noise floor is subtracted from the cross-polarization isolation time series to obtain the cross-polarization isolation degradation amount.

[0039] When the data is pointed at the cold air region by the radar antenna, the received brightness temperature values ​​of the horizontal polarization channel and the vertical polarization channel are recorded. The brightness temperature value is used as the actual measured value of the system noise temperature to calibrate the noise floor of the radar receiving system. In the subsequent calculation of the cross-polarization isolation degradation, the cross-polarization component contributed by the noise floor is subtracted from the cross-polarization isolation measurement value obtained from the metal ball calibration to obtain the polarization isolation degradation after the thermal noise effect of the system is eliminated. It should be noted that all the data collected above is stored in the memory of the radar control terminal in real time.

[0040] Step S2: Based on the antenna module interface displacement data and the antenna thermal cycling recording data, perform structural memory effect error assessment to obtain the cumulative assessment value of azimuth interface offset and the cumulative assessment value of pitch interface offset. The structural memory effect error assessment includes the following specific steps: Obtain the initial displacement value of the laser displacement sensor located at the antenna module connection flange after each assembly, as well as the thermal stress distribution cloud map on the back of the antenna; Using the thermal stress distribution cloud map on the back of the antenna as a boundary condition, the data is input into the pre-constructed contact stress recovery model of the connection interface between the antenna and the turntable to obtain the flange displacement vector relative to the antenna azimuth axis and the flange displacement vector relative to the pitch axis. It should be noted that the contact stress recovery model of the antenna-turntable connection interface is constructed using finite element analysis software (such as Abaqus or ANSYS). The specific steps are as follows: First, a detailed three-dimensional geometric model of the antenna module and the turntable connecting flange is established, defining material properties (such as elastic modulus, Poisson's ratio, and coefficient of thermal expansion) and contact pairs (coefficient of friction and contact stiffness). Then, the thermal stress distribution cloud map on the back of the antenna is applied to the model as a temperature load boundary condition to simulate the contact stress distribution at the flange interface under different thermal cycling conditions. Finally, the displacement field of the flange under different thermal stress states was calculated using a finite element solver, and the flange displacement vector relative to the antenna azimuth and elevation axes was extracted from it.

[0041] Based on the flange displacement vector of the antenna relative to the azimuth axis and the degree of offset of the actual centroid position of the antenna module relative to the designed centroid position, an azimuth interface offset accumulation analysis is performed. The azimuth interface offset accumulation analysis process is as follows: the length of the overlapping segment of the antenna azimuth flange displacement vector after two adjacent disassembly and assembly cycles is obtained and divided by the total envelope length of the antenna azimuth flange displacement vector after the corresponding two disassembly and assembly cycles to obtain the displacement retention rate between the corresponding two disassembly and assembly cycles. The displacement change rate is obtained by subtracting the displacement retention rate from 1. The displacement change rate is accumulated over each disassembly and assembly cycle to obtain the total azimuth offset accumulation of the corresponding antenna. The degree of deviation of the actual centroid position relative to the designed centroid position is obtained by measuring the antenna attitude change values ​​before and after disassembly using multiple high-precision tilt meters arranged on the antenna module, combined with the three-dimensional model of the antenna module to calculate the centroid position. The projection component of the vector offset of the actual centroid relative to the designed centroid on the azimuth axis is divided by a preset reference length (in this embodiment, the antenna aperture or wavelength) to obtain the azimuth centroid offset coefficient. The cumulative evaluation value of the azimuth interface offset of the corresponding antenna is obtained by multiplying the cumulative total azimuth offset of the corresponding antenna with the azimuth centroid offset coefficient. Based on the flange displacement vector of the antenna relative to the pitch axis and the degree of offset of the actual centroid position of the antenna module relative to the designed centroid position, the pitch interface offset cumulative analysis is performed. The calculation method is the same as that of the azimuth direction, and the pitch interface offset cumulative evaluation value is obtained.

[0042] Step S3: Based on the calibration reference source response data, perform electrical performance error assessment to obtain the electrical performance error assessment value of the horizontal polarization channel and the comprehensive performance error assessment value of the vertical polarization channel; The electrical performance error assessment includes the following specific steps: In calibration mode, the cross-polarization isolation time sequence, main lobe broadening coefficient and side lobe level rise of the antenna are extracted synchronously. At the same time, the surface temperature distribution cloud map is obtained by the thermocouple array buried on the back of the waveguide cavity, and the change in waveguide cavity wall thickness is recorded by laser thickness gauge. For the horizontally polarized channel, the main lobe widening coefficient and the side lobe level rise are extracted based on the radiation pattern test results. The relative deviations of the two from the calibration reference values ​​are calculated respectively. The main lobe widening deviation coefficient and the side lobe rise deviation coefficient are weighted and summed to obtain the electrical performance error evaluation value of the horizontally polarized channel. It should be noted that the calibration reference values ​​refer to the ideal or standard values ​​of the corresponding parameters measured before the antenna leaves the factory or during the most recent comprehensive calibration (when there are no major disassembly or thermal history changes). Specifically, these include: the reference value of the main lobe broadening coefficient of the horizontal polarization channel. Reference value for sidelobe level rise and the baseline value of the main lobe broadening factor of the vertical polarization channel Sidelobe level rise reference value and cross-polarization isolation reference value In another preferred embodiment, these reference values ​​are pre-stored in a radar calibration parameter database and used as a reference zero point for calculating the deviation of the current measurement value.

[0043] For the vertical polarization channel, in addition to the main lobe widening factor and sidelobe level rise, a cross-polarization isolation degradation factor is introduced as an evaluation dimension. It should be noted that this cross-polarization isolation degradation factor is also based on the cross-polarization isolation baseline value of the vertical polarization channel. Calculated; Simultaneously, the surface temperature distribution cloud map of the waveguide cavity and the wall thickness change are input into the pre-constructed thermo-mechanical coupling deformation prediction model to perform thermo-mechanical coupling deformation analysis and obtain the comprehensive performance error evaluation value of the vertical polarization channel. The acquisition of the cross-polarization isolation degradation includes: based on the cross-polarization isolation time series, subtracting the cross-polarization component contributed by the system noise floor to obtain the cross-polarization isolation degradation.

[0044] The overall performance error assessment of the vertical polarization channel specifically includes: Obtain the main lobe broadening coefficient and cross-polarization isolation degradation of the antenna's vertical polarization pattern, calculate the relative deviations of the two from the corresponding calibration reference values, and then weight and fuse the main lobe broadening deviation coefficient and the cross-polarization isolation degradation coefficient to obtain the basic electrical error assessment value of the vertical polarization channel. Meanwhile, based on the surface temperature distribution cloud map of the waveguide cavity, the known thermal expansion coefficient of the waveguide material, and the wall thickness change recorded by the laser thickness gauge, the residual deformation of the waveguide cavity under the current thermal history conditions is inferred through the thermo-mechanical coupling deformation prediction model. The construction of the thermo-mechanical coupling deformation prediction model includes, but is not limited to, the experimental calibration model construction method and the deep learning network model construction method; It should be noted that in this preferred embodiment, the deep learning network model adopts a multilayer perceptron or convolutional neural network structure. The training data comes from multiple sets of temperature time series data of thermocouple arrays accumulated in history and the wall thickness change data measured by laser thickness gauge at the corresponding time. The temperature time series data is used as input features and the measured wall thickness change is used as supervision label. The network weights are obtained by training through backpropagation algorithm. When using it, the temperature distribution cloud map at the current time is input into the network, and the residual deformation under the current thermal history conditions can be quickly deduced.

[0045] It should also be noted that, in another preferred embodiment, the thermo-mechanical coupling deformation prediction model is constructed using an experimental calibration method, the specific method of which is as follows: First, before the radar leaves the factory or during periodic calibration, the surface temperature distribution of the waveguide cavity under different temperature conditions is collected by a thermocouple array. At the same time, a laser thickness gauge is used to record the wall thickness change of the key section of the waveguide cavity under the corresponding conditions, and a temperature-deformation correspondence database is established. Then, based on the above database, a mapping relationship between temperature distribution and residual deformation is established by using polynomial fitting or interpolation methods to form an empirical model; Finally, when using it, input the currently measured temperature distribution cloud map into the model, and the model will output the corresponding residual deformation. It should be noted that the model is simple in form, requires little computation, and is based on measured data, thus meeting engineering requirements.

[0046] The ratio of the deduced residual deformation to the safe deformation of the waveguide cavity is used as the thermo-mechanical coupling deformation error coefficient. This coefficient is then weighted and fused with the basic electrical error assessment value of the vertical polarization channel to obtain the comprehensive performance error assessment value of the vertical polarization channel.

[0047] Step S4: Perform coupling error matching analysis using the cumulative evaluation value of the azimuth interface offset, the cumulative evaluation value of the pitch interface offset, the electrical performance error evaluation value of the horizontal polarization channel, and the comprehensive performance error evaluation value of the vertical polarization channel to obtain the comprehensive calibration error matching value. The coupling error matching analysis includes the following specific contents: The cumulative evaluation values ​​of azimuth and pitch interface offsets obtained from the structural memory effect error assessment, and the comprehensive performance error evaluation values ​​of the horizontal polarization channel and the vertical polarization channel obtained from the electrical performance error assessment are obtained. Considering that the azimuth interface offset mainly causes the reference deflection of the horizontal polarization channel, the cumulative evaluation value of the azimuth interface offset and the electrical performance error evaluation value of the horizontal polarization channel are weighted and summed to obtain the azimuth-horizontal coupling error. The pitch-to-interface offset mainly affects the polarization orthogonality of the vertical polarization channel. The pitch-to-vertical coupling error is obtained by weighted summing of the cumulative evaluation value of the pitch-to-interface offset and the comprehensive performance error evaluation value of the vertical polarization channel. The weighted sum of the two coupling errors is the comprehensive calibration error matching value.

[0048] Step S5: Provide a calibration status prompt based on the comprehensive calibration error matching value.

[0049] The generation of the calibration compensation coefficient includes the following specific contents: The comprehensive calibration error matching value is compared with the preset comprehensive error tolerance threshold: if the comprehensive calibration error matching value is less than the corresponding comprehensive error tolerance threshold, it is determined that the current calibration status meets the observation accuracy requirements, and a normal calibration status prompt is directly output, and the existing calibration parameters are used for subsequent rainfall measurement tasks; if the comprehensive calibration error matching value is greater than or equal to the corresponding comprehensive error tolerance threshold, the compensation coefficient generation process is entered. The compensation coefficient generation process specifically includes: First, based on the cumulative evaluation value of the azimuth interface offset and the cumulative evaluation value of the pitch interface offset obtained in step S2, and combined with the electrical performance error evaluation value of the horizontal polarization channel and the comprehensive performance error evaluation value of the vertical polarization channel obtained in step S3, the azimuth-horizontal coupling compensation factor and the pitch-vertical coupling compensation factor are constructed respectively. Among them, the azimuth-horizontal coupling compensation factor is calculated by the ratio of the cumulative evaluation value of the azimuth offset to the interface to the electrical performance error evaluation value of the horizontal polarization channel, and the pitch-vertical coupling compensation factor is calculated by the ratio of the cumulative evaluation value of the pitch offset to the interface to the comprehensive performance error evaluation value of the vertical polarization channel. Then, a 2×2 polarization compensation matrix is ​​constructed using the two compensation factors mentioned above as the main diagonal elements. This matrix is ​​used to correct the differential reflectivity factor and differential propagation phase shift measurement value of the dual polarization receiving channel in real time during subsequent rainfall measurement tasks. For example, in this embodiment, the specific correction method is as follows: Let the complex echo signal of the horizontal polarization channel be... The complex echo signal of the vertically polarized channel is This constitutes the complex echo signal vector. Multiply the vector on the left by the polarization compensation matrix. The corrected complex echo signal vector is obtained: ; in It is a 2×2 polarization compensation matrix, whose main diagonal elements are azimuth-horizontal coupling compensation factors and pitch-vertical coupling compensation factors, and the secondary diagonal elements are cross-polarization coupling coefficients.

[0050] After revision, by Calculate the power ratio of the horizontal and vertical channels to obtain the differential reflectivity factor. The phase difference between the horizontal and vertical channels is calculated to obtain the differential propagation phase shift. .

[0051] Finally, the generated compensation matrix is ​​written into the parameter memory of the radar signal processing unit, and a status prompt indicating that the calibration compensation is complete is output for the operator to confirm.

[0052] Example 2: like Figure 2 As shown in the figure, an error compensation system for the calibration of a rain-measuring radar antenna according to an embodiment of the present invention includes the following modules: The data acquisition module acquires antenna module interface displacement data, antenna thermal cycling record data, and calibration reference source response data. The structural memory effect evaluation module evaluates the structural memory effect error based on the antenna module interface displacement data and the antenna thermal cycling record data, and obtains the cumulative evaluation value of the azimuth interface offset and the cumulative evaluation value of the pitch interface offset. The electrical performance evaluation module performs electrical performance error evaluation based on the calibration reference source response data to obtain the electrical performance error evaluation value of the horizontal polarization channel and the comprehensive performance error evaluation value of the vertical polarization channel. The matching analysis module performs coupled error matching analysis using the cumulative evaluation value of the azimuth interface offset, the cumulative evaluation value of the pitch interface offset, the electrical performance error evaluation value of the horizontal polarization channel, and the comprehensive performance error evaluation value of the vertical polarization channel to obtain a comprehensive calibration error matching value. The compensation module provides calibration status prompts based on the comprehensive calibration error matching value.

[0053] Example 3: This embodiment provides an electronic device, including: a processor and a memory, wherein the memory stores a computer program that can be called by the processor; The processor executes the aforementioned error compensation method for calibrating a rain-measuring radar antenna by calling a computer program stored in memory.

[0054] The electronic device can vary considerably depending on its configuration or performance. It may include one or more processors (Central Processing Units, CPUs) and one or more memories, wherein the memory stores at least one computer program, which is loaded and executed by the processor to implement the error compensation method for rain-measuring radar antenna calibration provided in the above-described embodiment. The electronic device may also include other components for implementing its functions; for example, it may have wired or wireless network interfaces and input / output interfaces for data input and output. Details will not be elaborated upon in this embodiment.

[0055] Example 4: This embodiment proposes a computer-readable storage medium on which an erasable and rewritable computer program is stored. When the computer program runs on the computer device, it causes the computer device to perform the above-mentioned error compensation method for rain-measuring radar antenna calibration.

[0056] For example, computer-readable storage media can be read-only memory (ROM), random access memory (RAM), compact disc read-only memory (CD-ROM), magnetic tape, floppy disk, and optical data storage devices.

[0057] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0058] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, as a computer program product. A computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, all or part of the flow or function according to the embodiments of the present invention is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. Computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired network and / or wireless network. A computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more sets of available media. Available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media. Semiconductor media can be solid-state drives (SSDs).

[0059] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed in this invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0060] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0061] In the several embodiments provided by this invention, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only one method, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0062] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0063] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0064] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0065] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for error compensation of a rain measurement radar antenna calibration, characterized in that The method includes: Step S1: Obtain antenna module interface displacement data, antenna thermal cycling record data, and calibration reference source response data; Step S2: Based on the antenna module interface displacement data and the antenna thermal cycling recording data, perform structural memory effect error assessment to obtain the cumulative assessment value of azimuth interface offset and the cumulative assessment value of pitch interface offset. Step S3: Based on the calibration reference source response data, perform electrical performance error assessment to obtain the electrical performance error assessment value of the horizontal polarization channel and the comprehensive performance error assessment value of the vertical polarization channel; Step S4: Perform coupling error matching analysis using the cumulative evaluation value of the azimuth interface offset, the cumulative evaluation value of the pitch interface offset, the electrical performance error evaluation value of the horizontal polarization channel, and the comprehensive performance error evaluation value of the vertical polarization channel to obtain the comprehensive calibration error matching value. Step S5: Provide a calibration status prompt based on the comprehensive calibration error matching value.

2. The error compensation method for rain radar antenna calibration according to claim 1, characterized in that, The structural memory effect error assessment includes the following specific steps: Obtain the initial displacement value of the laser displacement sensor located at the antenna module connection flange after each assembly, as well as the thermal stress distribution cloud map on the back of the antenna; Using the thermal stress distribution cloud map on the back of the antenna as a boundary condition, the data is input into the pre-constructed contact stress recovery model of the connection interface between the antenna and the turntable to obtain the flange displacement vector relative to the antenna azimuth axis and the flange displacement vector relative to the pitch axis. Based on the flange displacement vector of the antenna relative to the azimuth axis and the degree of offset of the actual centroid position of the antenna module relative to the designed centroid position, an azimuth interface offset accumulation analysis is performed. The azimuth interface offset accumulation analysis process is as follows: the length of the overlapping segment of the antenna azimuth flange displacement vector after two adjacent disassembly and assembly cycles is obtained and divided by the total envelope length of the antenna azimuth flange displacement vector after the corresponding two disassembly and assembly cycles to obtain the displacement retention rate between the corresponding two disassembly and assembly cycles. The displacement change rate is obtained by subtracting the displacement retention rate from 1. The displacement change rate is accumulated over each disassembly and assembly cycle to obtain the total azimuth offset accumulation of the corresponding antenna. The degree of deviation of the actual centroid position relative to the designed centroid position is obtained by measuring the antenna attitude change values ​​before and after disassembly using multiple high-precision tilt gauges arranged on the antenna module, combined with the three-dimensional model of the antenna module to calculate the centroid position. The projection component of the vector offset of the actual centroid relative to the designed centroid on the azimuth axis is divided by the preset reference length to obtain the azimuth centroid offset coefficient. The cumulative evaluation value of the azimuth interface offset of the corresponding antenna is obtained by multiplying the cumulative total azimuth offset of the corresponding antenna with the azimuth centroid offset coefficient. Based on the flange displacement vector of the antenna relative to the pitch axis and the degree of offset of the actual centroid position of the antenna module relative to the designed centroid position, the pitch interface offset cumulative analysis is performed. The calculation method is the same as that of the azimuth direction, and the pitch interface offset cumulative evaluation value is obtained.

3. The error compensation method for rain radar antenna calibration according to claim 2, characterized in that, The electrical performance error assessment includes the following specific steps: In calibration mode, the cross-polarization isolation time sequence, main lobe broadening coefficient and side lobe level rise of the antenna are extracted synchronously. At the same time, the surface temperature distribution cloud map is obtained by the thermocouple array buried on the back of the waveguide cavity, and the change in waveguide cavity wall thickness is recorded by laser thickness gauge. For the horizontally polarized channel, the main lobe widening coefficient and the side lobe level rise are extracted based on the radiation pattern test results. The relative deviations of the two from the calibration reference values ​​are calculated respectively. The main lobe widening deviation coefficient and the side lobe rise deviation coefficient are weighted and summed to obtain the electrical performance error evaluation value of the horizontally polarized channel. For the vertical polarization channel, in addition to the main lobe broadening factor and the side lobe level rise, the cross-polarization isolation degradation is introduced as an evaluation dimension. At the same time, the waveguide cavity surface temperature distribution cloud map and the wall thickness change are input into the pre-constructed thermo-mechanical coupling deformation prediction model to perform thermo-mechanical coupling deformation analysis and obtain the comprehensive performance error evaluation value of the vertical polarization channel. The acquisition of the cross-polarization isolation degradation includes: based on the cross-polarization isolation time series, subtracting the cross-polarization component contributed by the system noise floor to obtain the cross-polarization isolation degradation.

4. The error compensation method for calibrating a rain-measuring radar antenna according to claim 3, characterized in that, The overall performance error assessment of the vertical polarization channel specifically includes: Obtain the main lobe broadening coefficient and cross-polarization isolation degradation of the antenna's vertical polarization pattern, calculate the relative deviations of the two from the corresponding calibration reference values, and then weight and fuse the main lobe broadening deviation coefficient and the cross-polarization isolation degradation coefficient to obtain the basic electrical error assessment value of the vertical polarization channel. Meanwhile, based on the surface temperature distribution cloud map of the waveguide cavity, the known thermal expansion coefficient of the waveguide material, and the wall thickness change recorded by the laser thickness gauge, the residual deformation of the waveguide cavity under the current thermal history conditions is inferred through the thermo-mechanical coupling deformation prediction model. The construction of the thermo-mechanical coupling deformation prediction model includes, but is not limited to, the experimental calibration model construction method and the deep learning network model construction method; The ratio of the deduced residual deformation to the safe deformation of the waveguide cavity is used as the thermo-mechanical coupling deformation error coefficient. This coefficient is then weighted and fused with the basic electrical error assessment value of the vertical polarization channel to obtain the comprehensive performance error assessment value of the vertical polarization channel.

5. The error compensation method for calibrating a rain-measuring radar antenna according to claim 4, characterized in that, The coupling error matching analysis includes the following specific contents: The cumulative evaluation values ​​of azimuth and pitch interface offsets obtained from the structural memory effect error assessment, and the comprehensive performance error evaluation values ​​of the horizontal polarization channel and the vertical polarization channel obtained from the electrical performance error assessment are obtained. The azimuth-horizontal coupling error is obtained by weighted summing of the cumulative evaluation value of the azimuth interface offset and the electrical performance error evaluation value of the horizontal polarization channel. The pitch-vertical coupling error is obtained by weighted summing of the cumulative evaluation value of the pitch interface offset and the comprehensive performance error evaluation value of the vertical polarization channel. The weighted sum of the two coupling errors is the comprehensive calibration error matching value.

6. The error compensation method for calibrating a rain-measuring radar antenna according to claim 5, characterized in that, The calibration status prompt includes calibration compensation coefficient generation, which includes the following specific content: The comprehensive calibration error matching value is compared with the preset comprehensive error tolerance threshold. If the comprehensive calibration error matching value is less than the corresponding comprehensive error tolerance threshold, the current calibration status is determined to meet the observation accuracy requirements. The calibration status is directly output as normal, and the existing calibration parameters are used for subsequent rainfall measurement tasks. If the overall calibration error matching value is greater than or equal to the corresponding overall error tolerance threshold, then proceed to the compensation coefficient generation process; The compensation coefficient generation process specifically includes: First, based on the cumulative evaluation value of the azimuth interface offset and the cumulative evaluation value of the pitch interface offset obtained in step S2, and combined with the electrical performance error evaluation value of the horizontal polarization channel and the comprehensive performance error evaluation value of the vertical polarization channel obtained in step S3, the azimuth-horizontal coupling compensation factor and the pitch-vertical coupling compensation factor are constructed respectively. Among them, the azimuth-horizontal coupling compensation factor is calculated by the ratio of the cumulative evaluation value of the azimuth offset to the interface to the electrical performance error evaluation value of the horizontal polarization channel, and the pitch-vertical coupling compensation factor is calculated by the ratio of the cumulative evaluation value of the pitch offset to the interface to the comprehensive performance error evaluation value of the vertical polarization channel. Then, a 2×2 polarization compensation matrix is ​​constructed using the two compensation factors mentioned above as the main diagonal elements. This matrix is ​​used to correct the differential reflectivity factor and differential propagation phase shift measurement value of the dual polarization receiving channel in real time during subsequent rainfall measurement tasks. Finally, the generated compensation matrix is ​​written into the parameter memory of the radar signal processing unit, and a status prompt indicating that the calibration compensation is complete is output for the operator to confirm.

7. The error compensation method for calibrating a rain-measuring radar antenna according to claim 6, characterized in that, The displacement data of the antenna module interface is collected by a laser displacement sensor located at the antenna connection flange after each disassembly and assembly and after each major thermal cycle cooling and stabilization, and the micro-displacement time sequence of the flange contact surface is recorded. The antenna thermal cycling recording data is acquired in real time through a multi-point thermocouple array embedded in the contact surface between the back of the waveguide cavity and the side box, and the radar transmission power duration and corresponding temperature change curve are recorded synchronously. The calibration reference source response data includes: The echo intensity and polarization response values ​​obtained during metal sphere calibration are used to extract the main lobe broadening coefficient, side lobe level rise, and cross-polarization isolation time sequence of the radiation pattern; The polarization brightness temperature data of the sky background noise is used to calibrate the noise floor of the radar receiving system, and the cross-polarization component contributed by the noise floor is subtracted from the cross-polarization isolation time series to obtain the cross-polarization isolation degradation amount.

8. An error compensation system for the calibration of a rain-measuring radar antenna, used to implement the error compensation method for the calibration of a rain-measuring radar antenna as described in any one of claims 1-7, characterized in that, The system includes the following modules: The data acquisition module acquires antenna module interface displacement data, antenna thermal cycling record data, and calibration reference source response data. The structural memory effect evaluation module evaluates the structural memory effect error based on the antenna module interface displacement data and the antenna thermal cycling record data, and obtains the cumulative evaluation value of the azimuth interface offset and the cumulative evaluation value of the pitch interface offset. The electrical performance evaluation module performs electrical performance error evaluation based on the calibration reference source response data to obtain the electrical performance error evaluation value of the horizontal polarization channel and the comprehensive performance error evaluation value of the vertical polarization channel. The matching analysis module performs coupled error matching analysis using the cumulative evaluation value of the azimuth interface offset, the cumulative evaluation value of the pitch interface offset, the electrical performance error evaluation value of the horizontal polarization channel, and the comprehensive performance error evaluation value of the vertical polarization channel to obtain a comprehensive calibration error matching value. The compensation module provides calibration status prompts based on the comprehensive calibration error matching value.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements an error compensation method for calibrating a rain-measuring radar antenna as described in any one of claims 1-7.

10. An electronic device, characterized in that, include: Memory, used to store instructions; A processor is configured to execute the instructions, causing the device to perform operations that implement the error compensation method for calibrating a rain-measuring radar antenna as described in any one of claims 1-7.

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