Two-dimensional interpolation amplitude-phase joint compensation phased array free-calibration sum-difference angle measurement method

Abstract

The application proposes a two-dimensional interpolation amplitude-phase joint compensation phased array free-calibration phase and difference angle measurement method, and belongs to the field of phased array data processing; the application proposes to construct an azimuth-elevation two-dimensional grid offline, prestore each pointing calibration phase zero value and difference amplitude correction factor; real-time tracking adopts two-dimensional bilinear interpolation to solve the phase zero value and amplitude compensation coefficient of any continuous pointing, synchronously completes difference beam amplitude inconsistency compensation, NCO phase initial phase configuration, down-conversion low-pass filtering angle error voltage solution, and then solves the angle deviation and closed-loop updates the beam pointing. The method realizes continuous free-calibration phase angle measurement in the detection range, suppresses the conformal array wide-angle amplitude distortion and channel amplitude-phase imbalance, improves the angle measurement precision and tracking stability, and is suitable for various conformal phased array radar measurement and control scenes.

Description

Technical Field

[0001] This invention relates to the field of phased array data processing, and in particular to a phased array angle measurement method without phase and difference compensation based on two-dimensional interpolation amplitude and phase joint compensation. Background Technology

[0002] With the rapid development of phased array technology, the application demand for conformal array antennas is increasing. Due to the asymmetric structure of conformal phased arrays, there are significant differences in the azimuth and elevation phase zero values ​​corresponding to different beam directions, which poses a huge challenge to the accuracy control of sum and difference beam angle measurement.

[0003] Traditional analog antennas have null phase values ​​independent of beam pointing, typically obtained by using beacon mounting or satellite-based phase calibration to obtain azimuth and elevation null phase values. However, in conformal phased arrays, multi-angle beacon mounting or UAV hovering for phase calibration is commonly used to obtain null phase values ​​for different beam pointings. This calibration process is complex and time-consuming. Furthermore, the acquired beam pointing exhibits high dispersion, and insufficient continuity can lead to tracking lock-off.

[0004] Therefore, in order to simplify the phase calibration method, reduce the phase calibration cost, and improve the tracking accuracy and continuity, a phase calibration-free angle measurement method is needed that can achieve continuous phase calibration within the detection range and simultaneously compensate for the inconsistency of sum and difference beam amplitudes, thus overcoming the shortcomings of existing technologies. Summary of the Invention

[0005] The purpose of this invention is to provide a two-dimensional interpolation amplitude-phase joint compensation phased array method for phase and difference angle measurement without phase calibration, so as to achieve high-precision phase and difference angle measurement of conformal phased arrays without phase calibration, with continuous measurement and joint compensation capabilities, and improve the angle measurement accuracy and continuity of conformal phased arrays.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] The method for measuring phase sum and difference angles of a phased array without phase and difference compensation based on two-dimensional interpolation amplitude and phase joint compensation includes the following steps:

[0008] Step 1: Based on the phased array structure parameters, construct a sum and difference beam simulation model, divide the detection airspace into a two-dimensional uniform grid of azimuth and elevation, and calculate the corresponding azimuth phase zero value, elevation phase zero value, azimuth amplitude correction factor and elevation amplitude correction factor for the beam pointing of each grid point through simulation, and integrate them into a two-dimensional interpolation matrix for storage.

[0009] Step 2: During real-time tracking, obtain the real-time pointing of the current beam, locate the grid cell in the two-dimensional interpolation matrix based on the real-time pointing, and extract the amplitude and phase parameters of the four vertices of the grid cell.

[0010] Step 3: Using the amplitude and phase parameters of the four vertices, the continuous azimuth phase zero value, continuous pitch phase zero value, real-time azimuth amplitude correction factor and real-time pitch amplitude correction factor corresponding to the current beam pointing are calculated by a two-dimensional bilinear interpolation algorithm.

[0011] Step 4: Based on the beam, carrier acquisition and tracking is achieved. The acquired NCO frequency is synchronized to the azimuth difference path NCO and the elevation difference path NCO. The initial phase of the two difference path NCOs is configured using the continuous azimuth phase zero value and the continuous elevation phase zero value, respectively. At the same time, the amplitude compensation of the azimuth difference beam signal and the elevation difference beam signal is performed using the real-time azimuth amplitude correction factor and the real-time elevation amplitude correction factor, respectively.

[0012] Step 5: Mix and downconvert the amplitude-compensated azimuth difference beam signal with the azimuth difference path NCO signal and perform low-pass filtering to extract the azimuth angle error voltage; mix and downconvert the amplitude-compensated pitch difference beam signal with the pitch difference path NCO signal and perform low-pass filtering to extract the pitch angle error voltage.

[0013] Step 6: Based on the azimuth error voltage and elevation error voltage, and combined with the pre-stored angle measurement sensitivity factor, calculate the azimuth deviation and elevation deviation, and update the current beam pointing.

[0014] Step 7: Use the updated beam pointing as the new current beam pointing, and repeat steps 2 to 6 to form a closed-loop iterative tracking.

[0015] Furthermore, the process of establishing the two-dimensional interpolation matrix in step 1 is as follows:

[0016] Based on the element distribution, spacing, and excitation parameters of the phased array, a sum-difference beam simulation model is constructed to generate sum beam signals, azimuth difference beam signals, and elevation difference beam signals within the detection range.

[0017] Within the azimuth scanning range [Az(min), Az(max)] and the elevation scanning range [El(min), El(max)], uniform grid division is performed according to preset steps ΔAz and ΔEl to form grid points (Az(n), El(m));

[0018] For each grid point, the differential beam signal amplitude is made zero by simulation to adjust the beamwidth, and the azimuth phase zero value at that point is calculated: Pitch-phase zero value: ;

[0019] in, The phase of the elevation difference beam signal at the current grid point. The phase of the azimuth difference beam signal at the current grid point;

[0020] Calculate the azimuth amplitude correction factor for each grid point. : ;

[0021] Pitch correction factor The calculation is as follows: ,

[0022] in, The amplitude of the current grid point and beam signal. The amplitude of the elevation difference beam signal at the current grid point. The amplitude of the azimuth difference beam signal at the current grid point;

[0023] Store the zero-value of phase correction and amplitude correction factor of all grid points according to grid coordinates, and construct a two-dimensional amplitude and phase parameter lookup table.

[0024] Furthermore, the two-dimensional bilinear interpolation algorithm in step 3 is as follows:

[0025] Let the current real-time pointing be (Az, El), and the four vertices of the grid cell be (Az(1), El(1)), (Az(1), El(2)), (Az(2), El(1)), (Az(2), El(2)), where Az is the azimuth angle of the current beam and El is the elevation angle of the current beam;

[0026] Calculate the normalized azimuth coefficient u: u = (Az - Az(1)) / (Az(2)-Az(1));

[0027] Normalized pitch coefficient v: v= (El - El(1)) / (El(2)-El(1));

[0028] Calculate the weight coefficients of the four vertices: w1=(1-u)(1-v), w2=(1-u)v, w3=u(1-v), w4=uv;

[0029] The amplitude and phase parameters of the four vertices are weighted and summed using weighting coefficients to obtain the continuous amplitude and phase parameters of the current point.

[0030] Furthermore, the amplitude-phase joint compensation process in step 4 is as follows:

[0031] The beam input carrier acquisition and tracking module outputs the reference NCO frequency ω_NCO and AGC parameters;

[0032] Synchronize the reference NCO frequency to the azimuth difference path NCO and the pitch difference path NCO to generate the azimuth difference path NCO signal: Pitch differential NCO signal: ,in , The continuous phase zero values ​​obtained by interpolation;

[0033] The original azimuth difference beam signal S_ΔA(t) is compensated using a real-time azimuth amplitude correction factor K_A. The compensation result is as follows: ;

[0034] The original pitch difference beam signal S_ΔE(t) is compensated using a real-time pitch amplitude correction factor K_E. The compensation result is as follows: ;

[0035] Furthermore, the specific process for extracting the angle error voltage in step 5 is as follows:

[0036] The azimuth error voltage U_A is proportional to the real part of the azimuth difference beam baseband signal after low-pass filtering, and the elevation error voltage U_E is proportional to the imaginary part of the elevation difference beam baseband signal after low-pass filtering.

[0037] Furthermore, the azimuth deviation in step 6 Az and pitch angle deviation The formulas for calculating El are as follows: Az = U_A / K_As, El = U_E / K_Es, where K_As is the azimuth angle measurement sensitivity factor and K_Es is the elevation angle measurement sensitivity factor, both of which are fixed constants calibrated by the system. The formula for updating the beam pointing is: Az_n = Az + Az, El_n = El + El, where (Az, El) is the current beam pointing and (Az_n, El_n) is the updated beam pointing.

[0038] Compared with the prior art, the present invention has the following advantages:

[0039] 1. By constructing a two-dimensional gridded amplitude and phase parameter matrix of azimuth and elevation, the zero value of phase correction and amplitude correction factor in the entire airspace are solved offline through simulation, realizing the conformal phased array without physical phase correction and simplifying the system process.

[0040] 2. By using a two-dimensional bilinear interpolation continuous solution mechanism, the discrete amplitude and phase parameters are extended into a continuous parameter field in the entire spatial domain, eliminating non-grid pointing angle step errors and improving the continuity and accuracy of angle measurement.

[0041] 3. By combining the compensation methods for sum and difference beam amplitude inconsistency and phase shift, channel amplitude imbalance and phase deviation are corrected simultaneously, improving angle measurement linearity and suppressing wide-angle scanning distortion.

[0042] 4. By constructing an integrated closed-loop angle measurement architecture, fully automatic tracking is achieved from simulation table building, interpolation calculation, amplitude and phase compensation to pointing update, thereby improving the stability and robustness of conformal array tracking. Attached Figure Description

[0043] Figure 1 The system workflow diagram provided by this invention;

[0044] Figure 2 This is a flowchart of beam signal processing for azimuth and elevation differences provided by the present invention.

[0045] Figure 3 This is a schematic diagram illustrating the azimuth-elevation two-dimensional grid and bilinear interpolation principle provided by the present invention. Detailed Implementation

[0046] In traditional conformal phased arrays, phase calibration is typically achieved by using multi-angle target mounting or UAV hovering to obtain zero-values ​​for different beam directions. This calibration process is complex and time-consuming. Furthermore, the acquired beam directions exhibit high dispersion and insufficient continuity, leading to tracking lock-off.

[0047] Reference Figures 1 to 3 This invention proposes a simplified phase calibration method based on two-dimensional interpolation amplitude-phase joint compensation for phased arrays, eliminating phase calibration and differential angle measurement. This method reduces calibration costs and improves tracking accuracy and continuity. The two-dimensional interpolation amplitude-phase joint compensation phased array method relies on a conformal phased array hardware platform and a digital signal processing module. It follows a workflow of "offline simulation table building—online interpolation calculation—amplitude-phase joint compensation—angle error calculation—closed-loop tracking," as shown in the system flowchart below. Figure 1 As shown, the specific implementation steps are as follows:

[0048] Step 1: Based on the phased array structure parameters, construct a sum-difference beam simulation model. Divide the detection airspace into a two-dimensional uniform grid for azimuth and elevation. For the beam pointing at each grid point, calculate the corresponding azimuth phase zero value, elevation phase zero value, azimuth amplitude correction factor, and elevation amplitude correction factor through simulation, and integrate them into a two-dimensional interpolation matrix for storage, as detailed below:

[0049] Based on the actual array structure of the conformal phased array antenna, system parameters such as element spatial distribution, operating frequency band, and scanning range are determined, and the design parameters conform to the characteristics of the conformal array structure and the angle measurement requirements. Based on the array parameters, a sum-difference beam simulation model is constructed to complete the signal simulation of the sum beam, azimuth difference beam, and elevation difference beam, and to obtain the standard complex signal expression form of each beam.

[0050] The complex signals for each beam are calculated as follows:

[0051] and beam signal:

[0052] Azimuth difference beam signal:

[0053] Pitch difference beam signal:

[0054] in: The beam amplitude is determined by the excitation amplitude of the array elements, the number of array elements, and the array gain. This represents the azimuth difference beam amplitude. The amplitude of the pitch difference beam is related to the element distribution and excitation method in the corresponding direction, and its amplitude is smaller than that of the beam amplitude. The signal angular frequency, , , The initial phases of the sum beam, azimuth difference beam, and elevation difference beam are determined by factors such as the initial phase of the array elements and the array layout.

[0055] Within the two-dimensional scanning space consisting of the azimuth and elevation dimensions, and considering the scanning range and angle measurement accuracy requirements of the conformal phased array, a uniform grid is decomposed according to a fixed angle interval. This discretizes the continuous two-dimensional space into several grid points, forming a discrete beam pointing grid. Each grid point corresponds to a unique beam pointing (Az(n), El(m)).

[0056] For each grid pointing (Az(n), El(m)), the simulation phase correction process is executed one by one to simulate the on-site phase correction logic. By beam deflection to make the difference beam amplitude zero, the azimuth phase zero value corresponding to that pointing is solved. Zero value of pitch phase This is used to compensate for the phase deviation between the difference beam and the sum beam in subsequent applications.

[0057]

[0058]

[0059] Simultaneously, based on the amplitude relationship between the sum and difference beams, the amplitude correction factor corresponding to the grid pointer is calculated to compensate for the amplitude imbalance between the sum and difference beams. The specific calculation formula is as follows:

[0060]

[0061]

[0062] After the calculation is complete, point all grids to the corresponding , , , Parameters are stored in high-speed memory according to grid coordinate order, and a two-dimensional amplitude and phase parameter lookup table is constructed to achieve offline parameter pre-storage.

[0063] Step 2: During real-time tracking, obtain the real-time pointing of the current beam, locate its grid cell in the two-dimensional interpolation matrix based on the real-time pointing, and extract the amplitude and phase parameters of the four vertices of that grid cell; specifically as follows:

[0064] After the system starts real-time tracking mode, it reads the actual pointing of the current beam in real time through the beam control system and angle sensor, denoted as (Az, El), to ensure the real-time performance and accuracy of the pointing data and adapt to high dynamic tracking requirements.

[0065] Based on the current beam pointing (Az, El), and combined with the constructed two-dimensional mesh, the two-dimensional mesh cell containing the beam is located through fast indexing and range comparison. The coordinates of the four vertices of this mesh cell are determined as (Az(1), El(1)), (Az(1), El(2)), (Az(2), El(1)), and (Az(2), El(2)). Subsequently, the amplitude and phase parameters corresponding to the four vertices are quickly read from the two-dimensional amplitude and phase parameter lookup table.

[0066] Vertex (Az(1), El(1)): Zero value of azimuth phase correction Pitch-phase zero value Azimuth amplitude correction factor Pitch correction factor ;

[0067] Vertex (Az(1), El(2)): Zero value of azimuth phase correction Pitch-phase zero value Azimuth amplitude correction factor Pitch correction factor ;

[0068] Vertex (Az(2), El(1)): Zero value of azimuth phase correction Pitch-phase zero value Azimuth amplitude correction factor Pitch correction factor ;

[0069] Vertex (Az(2), El(2)): Zero value of azimuth phase correction Pitch-phase zero value Azimuth amplitude correction factor Pitch correction factor .

[0070] Store in a temporary cache for subsequent interpolation calculations.

[0071] Step 3: Using the amplitude and phase parameters of the four vertices, calculate the continuous azimuth phase zero value, continuous elevation phase zero value, real-time azimuth amplitude correction factor, and real-time elevation amplitude correction factor corresponding to the current beam pointing using a two-dimensional bilinear interpolation algorithm; details are as follows:

[0072] Based on the relative position of the current beam pointing (Az, El) within its respective grid cell, the normalized azimuth coefficient u and normalized elevation coefficient v are calculated to quantify the relative distance between the current beam pointing and the grid vertex. The specific calculation formulas are as follows:

[0073]

[0074]

[0075] Based on the normalized coefficients u and v, the interpolation weights of the four grid vertices are further calculated to allocate the contribution of each vertex's amplitude and phase parameters to the interpolation result, ensuring the continuity and accuracy of the interpolation result. The weight calculation formula is as follows:

[0076]

[0077]

[0078]

[0079]

[0080] Using a weighted interpolation method, combining the calculated weight coefficients with the amplitude and phase parameters of the four vertices, the continuous amplitude and phase parameters corresponding to the current beam pointing (Az, El) are solved, as follows: Figure 3 As shown, the discrete mesh parameters are extended to continuous parameters across the entire spatial domain to eliminate non-mesh-oriented angular step errors. The specific calculation is as follows:

[0081] 1. Calculate the continuous azimuth phase zero value corresponding to the current pointing direction. :

[0082]

[0083] 2. Calculate the continuous pitch phasing zero value corresponding to the current pointing direction. :

[0084]

[0085] 3. Calculate the real-time azimuth amplitude correction factor corresponding to the current pointing direction. :

[0086]

[0087] 4. Calculate the real-time pitch correction factor corresponding to the current pointing direction. :

[0088]

[0089] After the calculation is completed, the above real-time amplitude and phase parameters are stored in a temporary cache for subsequent amplitude and phase joint compensation.

[0090] Step 4: Based on beamforming, carrier acquisition and tracking are implemented. The acquired NCO frequency is synchronized to the azimuth difference path NCO and the elevation difference path NCO. The initial phase of the two difference path NCOs is configured using continuous azimuth phase zero values ​​and continuous elevation phase zero values, respectively. Simultaneously, amplitude compensation is performed on the azimuth difference beam signal and the elevation difference beam signal using real-time azimuth amplitude correction factors and real-time elevation amplitude correction factors, respectively. Details are as follows:

[0091] Taking advantage of the high power and high signal-to-noise ratio of the sum beam, the sum beam signal obtained from the simulation in step 1 is input into the carrier acquisition and tracking module to complete the stable acquisition and tracking of the carrier frequency and phase, and output the system reference NCO (numerically controlled oscillator) frequency ω_NCO.

[0092] The reference NCO frequency ω_NCO is synchronized to the azimuth difference path NCO and the elevation difference path NCO to ensure that the frequency of the output signal of the two difference path NCOs is consistent with the frequency of the beam carrier. This provides a frequency reference for subsequent mixing downconversion and angle error calculation, and avoids angle measurement errors caused by frequency deviation.

[0093] Based on the real-time phase zero value obtained in step 5, azimuth difference path and elevation difference path NCO signals are generated respectively, with the specific expressions as follows:

[0094] The azimuth difference path NCO signal is:

[0095] The pitch differential NCO signal is:

[0096] in, , The current pointing continuous phase zero value obtained by interpolation is used to compensate for the phase deviation between the difference beam and the sum beam.

[0097] To eliminate angle measurement errors caused by gain imbalance in the sum and difference beam channels and amplitude distortion in wide-angle scanning, an interpolated real-time amplitude correction factor is used to perform amplitude equalization compensation on the original difference beam signal, ensuring that the amplitude of the difference beam matches the amplitude of the sum beam after compensation, thereby improving the accuracy of angle error calculation.

[0098] The specific calculation formula for amplitude compensation is as follows:

[0099] Azimuth difference beam compensation formula:

[0100]

[0101] Pitch difference beam compensation formula:

[0102]

[0103] Step 5: Perform frequency mixing, down-conversion, and low-pass filtering on the amplitude-compensated azimuth difference beam signal and the azimuth difference path NCO signal to extract the azimuth angle error voltage; perform frequency mixing, down-conversion, and low-pass filtering on the amplitude-compensated pitch difference beam signal and the pitch difference path NCO signal to extract the pitch angle error voltage; the details are as follows:

[0104] The amplitude-compensated difference beam signal is mixed with the corresponding difference path NCO signal. Using the principle of trigonometric function product-difference, the high-frequency difference beam signal is down-converted to baseband for subsequent angular error extraction. The specific mixing calculation is as follows:

[0105] 1. Azimuth difference beam mixing: Mixing the amplitude-compensated azimuth difference beam signal... With azimuth difference path NCO signal Multiply to obtain the mixed signal :

[0106]

[0107]

[0108]

[0109] 2. Pitch difference beam mixing: Mixing the amplitude-compensated pitch difference beam signal... With pitch differential NCO signal Multiply to obtain the mixed signal :

[0110]

[0111]

[0112]

[0113] The mixed signal contains a baseband DC component that reflects the angle deviation and a high-frequency second harmonic component that does not need to be retained. Therefore, for , Low-pass filtering is performed separately to remove the second harmonic high-frequency components and retain the baseband angular error signal. The cutoff angular frequency of the low-pass filter (LPF) must be less than the signal angular frequency ω to ensure that the second harmonic high-frequency components are completely filtered out while preserving the integrity of the baseband DC components.

[0114] Based on the orthogonal dual-channel design of this invention, azimuth error information is mapped to the real part of the azimuth difference roadbed error signal, and pitch error information is mapped to the imaginary part of the pitch difference roadbed error signal. By extracting the corresponding components, the azimuth error voltage and pitch error voltage are obtained. The specific extraction method is as follows:

[0115] By combining the extracted angular error voltage with the calibrated angular sensitivity factor of the system, the azimuth deviation between the current beam pointing and the actual target pointing is calculated. pitch angle deviation The specific calculation formula is as follows:

[0116] 1. Azimuth deviation The calculation formula is:

[0117]

[0118] in, The azimuth angle measurement sensitivity factor is obtained through system calibration from hardware parameters such as the array gain and differential beam slope of the conformal phased array, and is a fixed constant.

[0119] 2. Pitch angle deviation The calculation formula is:

[0120]

[0121] in, For elevation angle measurement sensitivity factor, and for azimuth angle measurement sensitivity factor The calibration method is consistent, and the calibration is obtained from the system hardware parameters, which are fixed constants.

[0122] Step 6: Based on the azimuth error voltage and elevation error voltage, and combined with the pre-stored angle measurement sensitivity factor, calculate the azimuth deviation and elevation deviation, and update the current beam pointing; details are as follows:

[0123] After the angle deviation calculation is completed, it is combined with the current beam pointing ( , The beam pointing is updated by offset compensation, so that the beam is shifted to the actual target direction, ensuring that the beam can be aligned with the target. The specific update principle is: add the current beam pointing to the corresponding angle deviation to obtain the updated beam pointing.

[0124] The formula for calculating beam pointing update is as follows:

[0125]

[0126]

[0127] in, , These are the azimuth and elevation directions of the current beam, respectively. , These are the updated azimuth and elevation directions of the beam. The updated beam direction is closer to the actual direction of the target, laying the foundation for subsequent closed-loop tracking.

[0128] Step 7: Use the updated beam pointing as the new current beam pointing, and repeat steps 2 to 6 to form a closed-loop iterative tracking.

[0129] Point the updated beam ( , As the new current beam pointing, the re-entering grid cell positioning stage sequentially completes the processes of grid positioning, interpolation coefficient calculation, amplitude and phase parameter interpolation, amplitude and phase joint compensation, angular error calculation, and pointing update, forming a closed-loop iterative tracking link. This closed-loop tracking process continues to iterate until the tracking task ends.

Claims

1. A phase and difference angle measurement method for phased arrays based on two-dimensional interpolation amplitude and phase joint compensation, characterized in that: Includes the following steps: Step 1: Based on the phased array structure parameters, construct a sum and difference beam simulation model, divide the detection airspace into a two-dimensional uniform grid of azimuth and elevation, and calculate the corresponding azimuth phase zero value, elevation phase zero value, azimuth amplitude correction factor and elevation amplitude correction factor for the beam pointing of each grid point through simulation, and integrate them into a two-dimensional interpolation matrix for storage. Step 2: During real-time tracking, obtain the real-time pointing of the current beam, locate the grid cell in the two-dimensional interpolation matrix based on the real-time pointing, and extract the amplitude and phase parameters of the four vertices of the grid cell. Step 3: Using the amplitude and phase parameters of the four vertices, the continuous azimuth phase zero value, continuous pitch phase zero value, real-time azimuth amplitude correction factor and real-time pitch amplitude correction factor corresponding to the current beam pointing are calculated by a two-dimensional bilinear interpolation algorithm. Step 4: Based on the beam, carrier acquisition and tracking is achieved. The acquired NCO frequency is synchronized to the azimuth difference path NCO and the elevation difference path NCO. The initial phase of the two difference path NCOs is configured using the continuous azimuth phase zero value and the continuous elevation phase zero value, respectively. At the same time, the amplitude compensation of the azimuth difference beam signal and the elevation difference beam signal is performed using the real-time azimuth amplitude correction factor and the real-time elevation amplitude correction factor, respectively. Step 5: Mix and downconvert the amplitude-compensated azimuth difference beam signal with the azimuth difference path NCO signal and perform low-pass filtering to extract the azimuth error voltage. The amplitude-compensated pitch difference beam signal and the pitch difference path NCO signal are mixed, down-converted and low-pass filtered to extract the pitch angle error voltage. Step 6: Based on the azimuth error voltage and elevation error voltage, and combined with the pre-stored angle measurement sensitivity factor, calculate the azimuth deviation and elevation deviation, and update the current beam pointing. Step 7: Use the updated beam pointing as the new current beam pointing, and repeat steps 2 to 6 to form a closed-loop iterative tracking.

2. The method for phased array angle measurement without phase and difference correction based on two-dimensional interpolation amplitude and phase joint compensation according to claim 1, characterized in that, The process of establishing the two-dimensional interpolation matrix in step 1 is as follows: Based on the element distribution, spacing, and excitation parameters of the phased array, a sum-difference beam simulation model is constructed to generate sum beam signals, azimuth difference beam signals, and elevation difference beam signals within the detection range. Within the azimuth scanning range [Az(min), Az(max)] and the elevation scanning range [El(min), El(max)], uniform grid division is performed according to preset steps ΔAz and ΔEl to form grid points (Az(n), El(m)); For each grid point, the differential beam signal amplitude was made zero through simulation by adjusting the beamwidth. Calculate the zero value of the azimuth phase correction at this point: Pitch-phase zero value: ; in, The phase of the elevation difference beam signal at the current grid point. The phase of the azimuth difference beam signal at the current grid point; Calculate the azimuth amplitude correction factor for each grid point. : ， Pitch correction factor The calculation is as follows: ， in The amplitude of the current grid point and beam signal. The amplitude of the elevation difference beam signal at the current grid point. The amplitude of the azimuth difference beam signal at the current grid point; Store the zero-value of phase correction and amplitude correction factor of all grid points according to grid coordinates, and construct a two-dimensional amplitude and phase parameter lookup table.

3. The method for phased array angle measurement without phase and difference correction based on two-dimensional interpolation amplitude and phase joint compensation according to claim 1, characterized in that, The specific two-dimensional bilinear interpolation algorithm in step 3 is as follows: Let the current real-time pointer be (Az, El). The four vertices of the grid cell are (Az(1), El(1)), (Az(1), El(2)), (Az(2), El(1)), (Az(2), El(2)). Where Az is the azimuth angle of the current beam and El is the elevation angle of the current beam; Calculate the normalized azimuth coefficient u: u = (Az - Az(1)) / (Az(2)-Az(1)) , Normalized pitch coefficient v: v= (El - El(1)) / (El(2)-El(1)) , Calculate the weight coefficients of the four vertices: w1=(1-u)(1-v), w2=(1-u)v, w3=u(1-v), w4=uv; The amplitude and phase parameters of the four vertices are weighted and summed using weighting coefficients to obtain the continuous amplitude and phase parameters of the current point.

4. The method for phased array angle measurement without phase and difference correction based on two-dimensional interpolation amplitude and phase joint compensation according to claim 1, characterized in that, The amplitude and phase combined compensation process in step 4 is as follows: The beam input carrier acquisition and tracking module outputs the reference NCO frequency ω_NCO and AGC parameters; Synchronize the reference NCO frequency to the azimuth difference path NCO and the elevation difference path NCO to generate Azimuth difference path NCO signal: , Pitch differential NCO signal: , in , The continuous phase zero values ​​obtained by interpolation; The original azimuth difference beam signal S_ΔA(t) is compensated using a real-time azimuth amplitude correction factor K_A. The compensation result is as follows: ， The original pitch difference beam signal S_ΔE(t) is compensated using a real-time pitch amplitude correction factor K_E. The compensation result is as follows: ； in, This represents the azimuth difference beam amplitude. The pitch difference beam amplitude; The signal angular frequency, To the amplitude of the beam signal, , These are the initial phases of the azimuth difference beam and the elevation difference beam, respectively.

5. The method for phased array angle measurement without phase and difference correction based on two-dimensional interpolation amplitude and phase joint compensation according to claim 1, characterized in that, The specific process for extracting the angle error voltage in step 5 is as follows: The azimuth error voltage U_A is proportional to the real part of the azimuth difference beam baseband signal after low-pass filtering, and the elevation error voltage U_E is proportional to the imaginary part of the elevation difference beam baseband signal after low-pass filtering.

6. The method for phased array angle measurement without phase and difference correction based on two-dimensional interpolation amplitude and phase joint compensation according to claim 1, characterized in that, Azimuth deviation in step 6 Az and pitch angle deviation The formulas for calculating El are as follows: Az = U_A / K_As, El = U_E / K_Es, where K_As is the azimuth angle measurement sensitivity factor and K_Es is the elevation angle measurement sensitivity factor, both of which are fixed constants calibrated by the system. The formula for updating the beam pointing is: Az_n = Az + Az, El_n = El + El, where (Az, El) is the current beam pointing and (Az_n, El_n) is the updated beam pointing.

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