Single pulse radar multi-angle discrimination angle curve fast generation method

Abstract

The present application belongs to the technical field of phased array radar monopulse and difference angle measurement, and particularly relates to a method for quickly generating angle discrimination curves of a monopulse radar at multiple pointing angles, which comprises the following steps: measuring the azimuth and elevation angle discrimination curves of the normal wave position of a phased array of a monopulse radar in a darkroom environment; scanning the beam pointing according to a designed trajectory, and synchronously rotating the turntable according to a corresponding designed trajectory to measure the difference and ratio data at the designed wave position; characterizing the deformation of the angle discrimination curves caused by the non-ideal factors of the phased array as translation and rotation, and calculating the translation coefficient C and the rotation factor K of the angle discrimination curves at different wave positions compared with the angle discrimination curves at the normal wave position based on the measured difference and ratio data; based on the obtained translation coefficient C and rotation factor K of the wave position, interpolating and predicting the C and K of all wave positions within the required wave position range; and based on the C and K of all wave positions, constructing a lookup table and writing it into the phased array radar to complete the quick generation of the angle discrimination curves of the monopulse radar at multiple pointing angles.

Description

Technical Field

[0001] This invention belongs to the field of single-pulse and differential angle measurement technology of phased array radar, specifically relating to a method for rapidly generating angle discrimination curves under multiple pointing angles in single-pulse radar. Background Technology

[0002] Monopulse angle measurement technology has wide applications in radar target detection and other fields. With the increasing complexity of modern battlefield environments, higher demands are placed on the accuracy of monopulse angle measurement technology to achieve precise target detection and guidance. The accuracy of monopulse sum-difference angle measurement technology is highly dependent on accurate angle discrimination curves. However, for phased array radar arrays, as the array electronically scans, the beam broadens and deforms. Simultaneously, non-ideal factors such as mutual coupling effects between array antenna elements, phase shifter quantization errors, and monopulse bridge errors cause distortions in the array antenna pattern that are difficult to model, leading to distortions in the angle discrimination curves at different wave positions. This severely affects the angle measurement accuracy of monopulse radar. In traditional angle discrimination curve measurement methods, to obtain an accurate angle discrimination curve for a specified wave position, it is necessary to fix the phased array radar on a high-precision turntable in an anechoic environment, place the feed antenna directly in front of the array surface, and perform complex spatial movements using the turntable. Specifically, when it is necessary to measure the azimuth and elevation angle discrimination curves of a certain wave position, a high-precision turntable must first align the phased array radar beam with the feed antenna, and then execute motion trajectories in the azimuth and elevation planes respectively. The phased array radar receives the signals transmitted by the feed antenna, uses the received amplitude and phase data to obtain the array antenna pattern, and then calculates the angle discrimination curve. However, the turntable movement process not only relies on a precise servo control system, but also requires the phased array to collect a large amount of data over a long period of time to obtain an accurate angle discrimination curve.

[0003] When a phased array radar system requires a large number of angle discrimination curves at different wave levels, the aforementioned turntable movement process needs to be repeated multiple times. For example, when the radar system needs to measure... The measurement time for the angle discrimination curve of each wave position will increase linearly. Especially in applications such as guided phased array radars that require the pre-storage of a large number of wave position angle discrimination curves, traditional methods exhibit significant efficiency problems. As the requirements for angle measurement accuracy in phased array radars continue to increase, efficient and accurate methods for acquiring single-pulse angle discrimination curves have become an important need.

[0004] Against this backdrop, researching rapid methods for obtaining angle discrimination curves for different beam pointing angles will effectively reduce the workload of anechoic chamber testing and improve the accuracy of radar single-pulse angle measurement. Currently, the sinusoidal space projection method is widely used. This method utilizes the fact that the array radiation pattern in the sinusoidal space coordinate system does not change with the beam scanning angle, but only shifts proportionally to the phase difference delay between adjacent radiating elements. Theoretically, the angle discrimination curves of different beam positions are the same after being projected into sinusoidal space. Using this principle, the azimuth and elevation angle discrimination curves of a certain beam position can be projected into sinusoidal space to obtain the angle discrimination curves of all beam positions. Sinusoidal space is a hemispherical mapping from three-dimensional space to a two-dimensional plane. Figure 2 The radar coordinate system shown has the following sinusoidal spatial transformation relationship:

[0005]

[0006] However, the sinusoidal spatial projection method cannot solve the distortion of the angle discrimination curve caused by non-ideal factors. The sinusoidal spatial projection method was verified by HFSS electromagnetic software simulation data and anechoic chamber measured data. The wave position of the angle discrimination curve in the simulation data includes azimuth and elevation angle combinations with 5° intervals from -30° to 30°, and the wave position of the angle discrimination curve in the measured data includes azimuth and elevation angle combinations with 10° intervals from -30° to 30°.

[0007] To evaluate the effectiveness of the sinusoidal spatial projection method, azimuth and elevation angle measurement errors are introduced. When using wave position... Angle measurement is performed using a complete angle-detection curve to obtain the target off-axis angle. , denoted as the reference value; using the above sinusoidal spatial projection method, the target in the beam direction was obtained. Off-axis angle The azimuth angle measurement error is defined as The pitch angle measurement error is .

[0008] Taking pitch angle measurement error as an example, Figure 1 These are the angular measurement errors using the sinusoidal spatial projection method, representing simulation data and measured data, respectively. The vertical axis represents the pitch angular measurement error. The x-axis ranges from 0° to 0.6°; the x-axis represents the off-axis angle, ranging from -3° to 3°, indicating the angle by which the target deviates from the beam's central axis; the different colored angle measurement error lines represent the angle measurement errors at different wave positions under the sinusoidal spatial projection method. The figure shows that the sinusoidal spatial projection method performs excellently in simulation data, with very small elevation angle measurement errors, indicating that the angle detection curves at different wave positions projected onto sinusoidal space are essentially the same, confirming the theoretical feasibility of the sinusoidal spatial projection method. However, this method performs poorly in actual measured data, with elevation angle measurement errors that cannot be ignored. This is due to various non-ideal factors such as mutual coupling effects in actual phased arrays, resulting in significant differences in the projection of angle detection curves at different wave positions onto sinusoidal space. This leads to errors in the angle detection curves obtained using the sinusoidal spatial projection method, severely reducing the angle measurement accuracy of the monopulse phased array radar. Summary of the Invention

[0009] The purpose of this invention is to provide a method for rapidly generating angle discrimination curves under multiple pointing angles in a single-pulse radar, so as to overcome the shortcomings of existing methods and significantly improve the angle discrimination curve generation speed and system real-time performance while ensuring the angle measurement accuracy of the angle discrimination curve.

[0010] The technical solution for implementing the present invention is as follows:

[0011] Firstly, a method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar is provided, the specific process of which is as follows: In an anechoic environment, a single-pulse radar phased array is fixed on a high-precision turntable, and the feed antenna is placed directly in front of the phased array's spatial position. The azimuth and elevation angle curves of the normal (0°, 0°) wave position are measured completely. The beam is directed to scan along the designed trajectory, and the turntable rotates synchronously along the corresponding set trajectory to measure the difference and ratio data under the designed beam position. The distortion of the angle discrimination curve caused by non-ideal factors of the phased array is characterized as translation and rotation. Based on the measured difference and ratio data, the translation coefficient C and rotation factor K of the angle discrimination curve of different wave positions relative to the normal wave position angle discrimination curve are calculated. Based on the translation coefficient C and rotation factor K of the obtained wave positions, interpolation is used to predict the translation coefficient C and rotation factor K of all wave positions within the required wave position range. Based on the translation coefficient C and rotation factor K of all wave positions, a lookup table is constructed and written into the phased array radar to complete the rapid generation of the angle discrimination curve under multiple pointing angles of the single-pulse radar.

[0012] Furthermore, the specific process for calculating the translation coefficient C and rotation factor K of different wave position discrimination curves relative to the normal wave position discrimination curve, as described in this invention, includes: (1) First, the normal wave position discrimination curve is mapped to sinusoidal space using the sinusoidal space projection method, and the mapped normal wave position discrimination curve is fitted. The expression is denoted as: , It is a difference and a comparison of data. It is the sinusoidal deflection after the off-axis angle is mapped to sinusoidal space; (2) For each wave position on the beam scanning trajectory, calculate the current wave position discrimination curve based on the measured difference and ratio data. The translation coefficient C and rotation factor K are calculated using the following formulas:

[0013] In the above formula, These are the difference and ratio data on the normal wave position discrimination curve. These are the difference and ratio data on the current wave position discrimination curve. according to The magnitude of the off-axis angle is determined accordingly on the normal angle curve.

[0014] Furthermore, the beam pointing according to the designed trajectory scanning of the present invention includes: (1) Before beam scanning, the monopulse radar was beam calibrated and the calibration table was burned. The corresponding beam control code was found according to the beam pointing calibration table, so that the beam could be scanned accurately according to the given trajectory. (2) Set the azimuth and elevation angle ranges of the required wave position as follows: and The azimuth and elevation angles of the scanning trajectory are set to have the following angular intervals: ; (3) The design of the beam scanning trajectory includes: centered on the origin, with... Multiple rectangular trajectories with n=0,1,2… as vertices are formed. The beam is electronically scanned sequentially along rectangular trajectories of different sizes until the beam azimuth or elevation angle is less than 0°.

[0015] Furthermore, the turntable of the present invention rotates synchronously along a corresponding preset trajectory, including: For each beam pointing on the scanning trajectory, the turntable attitude angle is calculated using the conversion relationship between the beam pointing angle and the turntable attitude angle. During beam scanning, the turntable movement is controlled to be synchronized with the beam scanning, so that beams pointing in different directions are always aligned with the feed antenna or offset by the same angle.

[0016] Furthermore, the present invention's description of beams pointing in different directions always being aligned with the feed antenna or offset by the same angle includes three cases: (1) When the beam is aligned with the feed antenna, the relationship between the turntable attitude and the beam pointing is as follows:

[0017] In the above formula, These are the beam pointing azimuth and elevation angles, respectively. These are the turntable's azimuth and pitch angles, respectively. (2) The beam deviates from the feed antenna in the azimuth plane by an off-axis angle Δ, and the conversion relationship between the two is as follows:

[0018] (3) The beam deviates from the feed antenna in the elevation plane by an off-axis angle Δ, and the conversion relationship between the two is as follows: .

[0019] Furthermore, the specific process for measuring the difference and ratio data under the designed wave position as described in this invention includes: (1) The phased array receives the signal transmitted by the feed antenna and records the amplitude and phase data of the signal received by the three ports of the phased array, namely the sum port, azimuth difference port, and elevation difference port, during this process. (2) Change the size and direction of the off-axis angle of the beam deviating from the feed antenna, and move the beam and turntable synchronously again. At the same time, record the amplitude and phase data of the signals received by the three ports of the phased array during this process, and finally obtain the port amplitude and phase data at different off-axis angles under the design wave position. (3) Based on the port data with different off-axis angles and different deviation directions received by the phased array, the azimuth difference port data and the pitch difference port data are compared with the sum port data to obtain the azimuth difference sum ratio and the pitch difference sum ratio.

[0020] Furthermore, the C and K values ​​for all wavelengths within the required wavelength range for interpolation prediction described in this invention include: Based on the C and K coefficients of the wave positions on the beam scanning trajectory, C and K matrices are constructed respectively, with the horizontal and vertical directions representing the azimuth and elevation angles of the wave positions. The C and K coefficients of other wave positions not covered by the beam scanning trajectory are predicted by interpolation.

[0021] Furthermore, the interpolation method described in this invention includes, but is not limited to, third-order spline interpolation or natural domain interpolation.

[0022] Furthermore, the present invention describes constructing a lookup table and writing it into a phased array radar to rapidly generate the angle discrimination curve under multiple pointing angles of a single-pulse radar, including: When generating the angle discrimination curve for a specific wavefront, the C and K coefficients for that wavefront are found using a lookup table in the radar, and the angle discrimination curve expression for that wavefront is quickly generated. The angle identification curve is an azimuth angle identification curve and / or an elevation angle identification curve.

[0023] Beneficial effects: The present invention provides a method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar. It characterizes the deformation of the angle discrimination curve caused by non-ideal factors in phased arrays as translation C and rotation K. By synchronously moving the beam and turntable, it rapidly measures the difference and ratio data of different wave positions to determine the coefficients C and K. Even with only the coefficients C and K of some wave positions determined, it can predict the C and K of all wave positions within the required wave position range, rapidly generating angle discrimination curves under multiple pointing angles. Compared to methods that require complete measurement of the angle discrimination curve for each wave position, the method provided by this invention only needs to measure the difference and ratio data under the design wave position to determine the coefficients C and K, reducing the workload of anechoic chamber testing, saving manpower and experimental resources, and significantly improving testing efficiency. Compared to the sinusoidal spatial projection method, the method provided by this invention significantly reduces the angle measurement error caused by non-ideal factors and improves the angle measurement accuracy of monopulse radar. Attached Figure Description

[0024] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used 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.

[0025] Figure 1 A schematic diagram of the angle measurement error using the sinusoidal spatial projection method for simulation data and measured data, (a) simulation data, (b) measured data; Figure 2 This is a schematic diagram of the radar coordinate system and the global coordinate system; Figure 3 A flowchart illustrating the method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar provided by the present invention; Figure 4 This is a schematic diagram of the beam pointing scanning trajectory in the radar coordinate system provided in an embodiment of the present invention; Figure 5 A schematic diagram of one rectangular trajectory of the beam scanning trajectory provided in an embodiment of the present invention; Figure 6 A schematic diagram comparing the first and second trajectories of the turntable in the global coordinate system, provided in an embodiment of the present invention. Figure 7 A schematic diagram comparing the motion trajectories of the first and third trajectories of the turntable in the global coordinate system, provided in an embodiment of the present invention. Figure 8 A schematic diagram of the angle measurement error using the method of the present invention for the measured data provided in the embodiments of the present invention. Detailed Implementation

[0026] To further illustrate the principles, processes, and advantages of the present invention, exemplary embodiments will be described in detail below with reference to the accompanying drawings. It should be noted that the verification methods primarily used in the embodiments described below are only for further explanation of the present invention and do not represent all implementations of the methods proposed in this invention.

[0027] like Figure 3 As shown in the figure, this application provides a method for rapidly generating angle discrimination curves under multiple pointing angles in a single-pulse radar. The specific process is as follows: S1: In an anechoic environment, fix the phased array on a high-precision turntable, place the feed antenna directly in front of the phased array, and measure the azimuth and elevation angle curves of the normal (0°, 0°) wave position. S2: The beam is pointed and scanned according to the design trajectory. The turntable rotates synchronously according to the corresponding set trajectory to measure the difference and ratio data under the design beam position. S3: The deformation of the angle discrimination curve caused by the non-ideal factors of the phased array is characterized as translation and rotation. Based on the measured difference and ratio data, the translation coefficient C and rotation factor K of the angle discrimination curve of different wave positions relative to the normal wave position angle discrimination curve are calculated. S4: Based on the translation coefficient C and rotation factor K of the obtained wave positions, interpolate to predict C and K for all wave positions within the required wave position range; S5: Based on the C and K of all the wave positions, construct a lookup table and write it into the phased array radar to complete the rapid generation of the angle discrimination curve under multiple pointing angles of the single pulse radar.

[0028] In step S2, the beam pointing is scanned according to the designed trajectory, specifically including: (1) Before beam scanning, the phased array radar has been beam calibrated and the calibration table has been burned. The corresponding beam control code is found according to the beam pointing calibration table, so that the beam can be scanned accurately according to the given trajectory. (2) Set the azimuth and elevation angle ranges of the required wave position to be (-30°, 30°), and set the azimuth and elevation angle intervals of the scanning trajectory to be 5°. (3) The designed beam scanning trajectory includes: centered on the origin, with... Multiple rectangular trajectories with vertices n=0,1,2… are used. The beam is electronically scanned sequentially along rectangular trajectories of different sizes until the beam azimuth or elevation angle is less than 0°.

[0029] The beam scanning trajectory diagram of this embodiment is shown below. Figure 4 As shown, the trajectory in the figure is only an example and is not the only implementation.

[0030] In step S2, the turntable rotates synchronously along a set trajectory to measure the difference and ratio data under the designed wave position, specifically including: For each beam pointing along the scanning trajectory, the turntable attitude angle is calculated using the conversion relationship between the beam pointing angle and the turntable attitude angle. During beam scanning, the turntable movement is controlled to synchronize with the beam scanning, ensuring that beams pointing in different directions are always aligned with the feed antenna or offset by the same angle. The radar coordinate system and the global coordinate system are as follows: Figure 2 As shown, the beam pointing is defined in the radar coordinate system, and the turntable attitude is defined in the global coordinate system. like Figure 5 As shown, an example is a rectangular trajectory with (20°, 20°) as the vertex in the beam scanning trajectory. The example selects a beam scanning trajectory from A (20°, -20°) to B (20°, 20°), and then from C (-20°, 20°) and D (-20°, -20°) back to A. (1) The beam is scanned for the first time according to the trajectory ABCD. In order to achieve beam alignment with the feed antenna, the conversion relationship between the turntable attitude and the beam pointing is as follows:

[0031] In the above formula, These are the beam pointing azimuth and elevation angles, respectively. These are the azimuth and pitch angles of the turntable attitude, respectively. Using this conversion formula to calculate the beam trajectory ABCD, the corresponding turntable attitude trajectory is A′B′C′D′, as shown below. Figure 6 The first trajectory of the transfer station is shown; (2) The beam is scanned a second time according to the trajectory ABCD. In order to make the beam deviate from the feed antenna in the azimuth plane, the half-power beamwidth of the radar used is 8°, and the deviation angle is the off-axis angle Δ = 2°. The conversion relationship between the two is as follows:

[0032] (3) The beam is scanned for the third time according to the trajectory ABCD. In order to make the beam deviate from the feed antenna in the elevation plane, and the deviation angle is the off-axis angle Δ = 2°, the conversion relationship between the two is as follows:

[0033] Each time the beam and turntable move synchronously, the radar records the amplitude and phase data of the signals received by the three ports of the phased array during this process. Furthermore, in steps (2) and (3) above, to improve measurement efficiency, the beam performs a second scan according to trajectory ABCD, which can measure the difference and ratio data of the elevation angle curve of part of the pointing direction and the azimuth angle curve of the remaining pointing direction. The turntable attitude is as follows... Figure 6 The second trajectory is shown in the diagram. Specifically, for the vertical portions AB and CD of the beam trajectory, this step measures the difference and ratio data on the azimuth discrimination curve; for the horizontal portions BC and DA of the beam trajectory, this step measures the difference and ratio data on the elevation discrimination curve.

[0034] When the beam scans for the third time along trajectory ABCD, to supplement the missing elevation angle difference and ratio data for beam trajectories AB and CD, and the missing azimuth angle difference and ratio data for beam trajectories BC and DA, the turntable attitude is as follows: Figure 7 The third trajectory is shown. Specifically, for the vertical portions AB and CD of the beam trajectory, this step measures the difference and ratio data of the elevation angle curves; for the horizontal portions BC and DA of the beam trajectory, this step measures the difference and ratio data of the azimuth angle curves. After this step, Figure 5 The difference and ratio data of the azimuth and elevation angles on the beam pointing ABCD with an off-axis angle of 2° were obtained.

[0035] In step S3, the translation coefficient C and rotation factor K of different wave position identification curves relative to the normal wave position identification curve are calculated. The specific process includes: (1) First, the normal wave position discrimination curve is mapped to sinusoidal space using the sinusoidal space projection method, and the mapped normal wave position discrimination curve is fitted. The expression is denoted as: y represents the difference and ratio data, and x represents the sinusoidal deflection after the off-axis angle is mapped to the sinusoidal space; (2) For each wave position on the beam scanning trajectory, calculate the current wave position discrimination curve based on the measured difference and ratio data. The translation coefficient C and rotation factor K are calculated using the following formulas:

[0036] In the above formula, These are the difference and ratio data on the current wave position discrimination curve, with corresponding off-axis angles of 0° and 2°, respectively. according to The magnitude of the off-axis angle is determined accordingly on the normal angle curve.

[0037] In step S4, the interpolation prediction of C and K for all wavelengths within the required wavelength range includes: Based on the C and K coefficients of the wave positions on the beam scanning trajectory, C and K matrices are constructed respectively, with the horizontal and vertical directions representing the azimuth and elevation angles of the wave positions. The C and K coefficients of other wave positions not covered by the beam scanning trajectory are predicted by the natural domain interpolation method. In step S5, a lookup table is constructed and written into the phased array radar to rapidly generate the angle discrimination curve under multiple pointing angles of the monopulse radar, including: When generating the angle discrimination curve for a specific wavefront, the C and K coefficients for that wavefront are found using a lookup table in the radar, and the angle discrimination curve expression for that wavefront is quickly generated. This method and its steps are applicable to both orientation and pitch angle curves.

[0038] Utilizing wave position Angle measurement is performed using a complete angle-detection curve to obtain the target off-axis angle. This value is recorded as a reference value; the angle is measured using the angle discrimination curve expression quickly generated by this method, and the target's position in the beam direction is obtained. Off-axis angle The azimuth angle measurement error is defined as... The pitch angle measurement error is .

[0039] Based on the specific implementation steps S1-S5 of the above method, taking elevation angle measurement error as an example, wave positions outside the beam scanning trajectory were selected for verification. Without loss of generality, 64 wave positions were selected. The elevation angle measurement error results are as follows: Figure 8 As shown, the vertical axis represents the pitch angle measurement error. The x-axis ranges from 0° to 0.6°; the x-axis represents the off-axis angle, ranging from -3° to 3°, indicating the angle by which the target deviates from the beam center axis; the different colored angle measurement error lines represent the angle measurement errors at different beam positions under this method. As shown in the figure, this method, compared to... Figure 1 (b) The sinusoidal spatial projection method significantly reduces the angle measurement error, with the error result basically below 0.05°.

[0040] The present invention provides a method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar. It characterizes the deformation of the angle discrimination curve caused by non-ideal factors in phased arrays as translation C and rotation K. By synchronously moving the beam and turntable, it rapidly measures the difference and ratio data under the design wave positions to determine the coefficients C and K. Even with only the coefficients C and K for a portion of the wave positions determined, it can predict the C and K for all wave positions within the required wave position range, thus rapidly generating angle discrimination curves under multiple pointing angles. Compared to methods that require complete measurement of the angle discrimination curve for each wave position, the method provided by this invention reduces the workload of anechoic chamber testing, saves manpower and experimental resources, and significantly improves testing efficiency. Compared to the sinusoidal spatial projection method, the method provided by this invention significantly reduces the angle measurement error caused by non-ideal factors and improves the angle measurement accuracy of monopulse radar.

[0041] It should be noted that in the description of this invention, terms such as "first" and "second" are used for illustrative purposes only and are not intended to indicate or imply relative importance. Furthermore, in the description of this application, unless otherwise expressly stated, the word "a plurality of" refers to at least two.

[0042] Any process or method described in this invention, whether in flowcharts or otherwise, can be understood as including a code module, segment, or portion of executable instructions for performing a specific logical function or process. The scope of the preferred embodiments of this invention also includes other implementations that may not be in the order shown, as will be understood by those skilled in the art.

[0043] It is understood that when terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples" are used to describe this invention, they refer to at least one embodiment or example having a particular feature, structure, material, or characteristic. The use of these terms does not necessarily involve the same embodiment or example, and the specific features, structures, materials, or characteristics described may be appropriately combined in one or more embodiments or examples.

[0044] The above detailed embodiments further illustrate the purpose, technical methods, and beneficial effects of the present invention. It should be understood that the above description is merely a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for rapidly generating angle discrimination curves under multiple pointing angles in a single-pulse radar, characterized in that, The specific process is as follows: In an anechoic environment, a single-pulse radar phased array is fixed on a high-precision turntable, and the feed antenna is placed directly in front of the phased array's spatial position. The azimuth and elevation angle curves of the normal (0°, 0°) wave position are measured completely. The beam is directed to scan along the designed trajectory, and the turntable rotates synchronously along the corresponding set trajectory to measure the difference and ratio data under the designed beam position. The distortion of the angle discrimination curve caused by non-ideal factors of the phased array is characterized as translation and rotation. Based on the measured difference and ratio data, the translation coefficient C and rotation factor K of the angle discrimination curve of different wave positions relative to the normal wave position angle discrimination curve are calculated. Based on the translation coefficient C and rotation factor K of the obtained wave positions, interpolation is used to predict the translation coefficient C and rotation factor K of all wave positions within the required wave position range. Based on the translation coefficient C and rotation factor K of all wave positions, a lookup table is constructed and written into the phased array radar to complete the rapid generation of the angle discrimination curve under multiple pointing angles of the single-pulse radar.

2. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 1, characterized in that, The specific process for calculating the translation coefficient C and rotation factor K of different wave position angle curves relative to the normal wave position angle curve includes: (1) First, the normal wave position discrimination curve is mapped to sinusoidal space using the sinusoidal space projection method, and the mapped normal wave position discrimination curve is fitted. The expression is denoted as: , It is a difference and a comparison of data. It is the sinusoidal deflection after the off-axis angle is mapped to sinusoidal space; (2) For each wave position on the beam scanning trajectory, calculate the current wave position discrimination curve based on the measured difference and ratio data. The translation coefficient C and rotation factor K are calculated using the following formulas: In the above formula, These are the difference and ratio data on the normal wave position discrimination curve. These are the difference and ratio data on the current wave position discrimination curve. according to The magnitude of the off-axis angle is determined accordingly on the normal angle curve.

3. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 2, characterized in that, The beam pointing is scanned according to the designed trajectory, including: (1) Before beam scanning, the monopulse radar was beam calibrated and the calibration table was burned. The corresponding beam control code was found according to the beam pointing calibration table, so that the beam could be scanned accurately according to the given trajectory. (2) Set the azimuth and elevation angle ranges of the required wave position as follows: and The azimuth and elevation angles of the scanning trajectory are set to have the following angular intervals: ; (3) The design of the beam scanning trajectory includes: centered on the origin, with... Multiple rectangular trajectories with n=0,1,2… as vertices are formed. The beam is electronically scanned sequentially along rectangular trajectories of different sizes until the beam azimuth or elevation angle is less than 0°.

4. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 3, characterized in that, The turntable rotates synchronously along a predetermined trajectory, including: For each beam pointing on the scanning trajectory, the turntable attitude angle is calculated using the conversion relationship between the beam pointing angle and the turntable attitude angle. During beam scanning, the turntable movement is controlled to be synchronized with the beam scanning, so that beams pointing in different directions are always aligned with the feed antenna or offset by the same angle.

5. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 4, characterized in that, The statement that beams pointing in different directions are always aligned with the feed antenna or offset by the same angle includes three cases: (1) When the beam is aligned with the feed antenna, the relationship between the turntable attitude and the beam pointing is as follows: In the above formula, These are the beam pointing azimuth and elevation angles, respectively. These are the turntable's azimuth and pitch angles, respectively. (2) The beam deviates from the feed antenna in the azimuth plane by an off-axis angle Δ, and the conversion relationship between the two is as follows: (3) The beam deviates from the feed antenna in the elevation plane by an off-axis angle Δ, and the conversion relationship between the two is as follows: 。 6. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 5, characterized in that, The off-axis angle Δ is one-quarter of the half-power beamwidth.

7. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 2, characterized in that, The specific process for measuring the difference and ratio data under the designed wave position includes: (1) The phased array receives the signal transmitted by the feed antenna and records the amplitude and phase data of the signal received by the three ports of the phased array, namely the sum port, azimuth difference port, and elevation difference port, during this process. (2) Change the size and direction of the off-axis angle of the beam deviating from the feed antenna, and move the beam and turntable synchronously again. At the same time, record the amplitude and phase data of the signals received by the three ports of the phased array during this process, and finally obtain the port amplitude and phase data at different off-axis angles under the design wave position. (3) Based on the port data with different off-axis angles and different deviation directions received by the phased array, the azimuth difference port data and the pitch difference port data are compared with the sum port data to obtain the azimuth difference sum ratio and the pitch difference sum ratio.

8. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 2, characterized in that, The interpolation prediction requires C and K for all positions within the required wave position range, including: Based on the C and K coefficients of the wave positions on the beam scanning trajectory, C and K matrices are constructed respectively, with the horizontal and vertical directions representing the azimuth and elevation angles of the wave positions. The C and K coefficients of other wave positions not covered by the beam scanning trajectory are predicted by interpolation.

9. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 8, characterized in that, The interpolation method is third-order spline interpolation or natural domain interpolation.

10. The method for rapidly generating angle discrimination curves under multiple pointing angles in monopulse radar according to claim 8, characterized in that, The construction of the lookup table and its writing into the phased array radar, used to rapidly generate the angle discrimination curve under multiple pointing angles of the monopulse radar, includes: When generating the angle discrimination curve for a specific wavefront, the C and K coefficients for that wavefront are found using a lookup table in the radar, and the angle discrimination curve expression for that wavefront is quickly generated. The angle identification curve is an azimuth angle identification curve and / or an elevation angle identification curve.

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