Two-dimensional joint angle measurement method and device based on sum-difference beam, equipment, medium

Abstract

The application provides a two-dimensional joint angle measurement method and device based on sum-difference beams, a device, equipment and medium. On the basis of a traditional angle measurement method, an initial angle measurement value is corrected by improving an angle measurement polynomial and adopting a two-dimensional angle joint iteration method, so as to weaken the influence of two-dimensional mutual coupling in angle measurement, and finally the two-dimensional angle measurement precision is obviously improved. The angle measurement precision when deviating from the beam center can be obviously improved, and the target acquisition time of a tracking radar is shortened.

Description

Technical Field

[0001] This invention belongs to the field of radar technology, and specifically relates to a two-dimensional joint angle measurement method, device, equipment, and medium based on sum and difference beams. Background Technology

[0002] As tracking radar demands higher angle measurement accuracy, traditional sum-difference amplitude ratio angle measurement methods are insufficient for application needs. This is primarily manifested in the gradual deterioration of two-dimensional angle measurement accuracy as the beam deviates from its center, leading to increased target acquisition time before tracking and potentially even target loss. Traditional sum-difference amplitude ratio angle measurement measures the elevation and azimuth dimensions separately, using their respective angle measurement polynomials or mapping tables to map the amplitude ratio measurements to angles, neglecting the cross-coupling effect of amplitude ratios on angle measurement. In reality, within the main lobe, the mapping relationship between the sum-difference beam amplitude ratio and the two-dimensional angle is two-dimensionally coupled. The mapping relationship between the azimuth amplitude ratio and the azimuth angle differs across different elevation angle sections; similarly, the mapping relationship between the elevation amplitude ratio and the elevation angle differs across different azimuth angle sections. Therefore, classic sum-difference beam measurement exhibits larger angle measurement errors at the beam edges, while the target angle measurement error decreases as the beam gradually locks onto the target. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, the inventors have conducted intensive research and provided a two-dimensional joint angle measurement method based on sum and difference beams. On the basis of traditional angle measurement methods, by improving the angle measurement polynomial, a two-dimensional angle joint iteration method is used to correct the initial angle measurement value, so as to weaken the influence of two-dimensional mutual coupling during angle measurement. Ultimately, the accuracy of two-dimensional angle measurement is significantly improved, which can significantly improve the angle measurement accuracy when deviating from the beam center and shorten the target acquisition time of the tracking radar.

[0004] The technical solution provided by this invention is as follows:

[0005] Firstly, a two-dimensional joint angle measurement method based on sum and difference beams includes the following steps:

[0006] Establish azimuth and elevation angle measurement mapping relationships;

[0007] The final azimuth and elevation angles are determined iteratively by using the azimuth and elevation angle mapping relationships.

[0008] Secondly, a two-dimensional joint angle measurement device based on sum and difference beams includes:

[0009] The first module is used to establish azimuth and elevation angle measurement mapping relationships;

[0010] The second module is used to iteratively determine the final azimuth and elevation angles by utilizing the azimuth and elevation angle mapping relationships.

[0011] Thirdly, a two-dimensional joint angle measuring device based on sum and difference beams includes:

[0012] One or more processors;

[0013] Storage device for storing one or more programs.

[0014] When the one or more programs are executed by the one or more processors, the one or more processors implement the two-dimensional joint angle measurement method based on sum and difference beams as described in the first aspect.

[0015] Fourthly, a readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the two-dimensional joint angle measurement method based on sum and difference beams as described in the first aspect.

[0016] The two-dimensional joint angle measurement method, apparatus, device, and medium based on sum-difference beams provided by the present invention have the following beneficial effects:

[0017] (1) The present invention provides a two-dimensional joint angle measurement method based on sum and difference beams. On the basis of the traditional angle measurement method, the initial angle measurement value is corrected by improving the angle measurement polynomial and adopting a two-dimensional angle joint iteration method to weaken the influence of two-dimensional mutual coupling during angle measurement. In the end, the accuracy of two-dimensional angle measurement is significantly improved, which can significantly improve the angle measurement accuracy when deviating from the beam center and shorten the target acquisition time of the tracking radar.

[0018] (2) The two-dimensional joint angle measurement method based on sum and difference beams provided by this invention takes into account the two-dimensional coupling characteristics, which is more in line with the actual variation law of the sum and difference amplitude. Through polynomial fitting method, the number of parameters is small. By using simple polynomial calculation and combining a small number of iterations, relatively accurate two-dimensional angle measurement results can be obtained, which can significantly improve the angle measurement accuracy when deviating from the beam center and shorten the target acquisition time of the tracking radar. Attached Figure Description

[0019] Figure 1 This is a flowchart of a two-dimensional joint angle measurement method based on sum and difference beams;

[0020] Figure 2 For the two-dimensional beam pattern;

[0021] Figure 3 This is a two-dimensional azimuth difference beam pattern;

[0022] Figure 4 This is a two-dimensional radiation pattern for the pitch difference beam;

[0023] Figure 5 Normalized azimuth difference beam (the thick line in the middle represents the tangent at the 0-degree elevation angle);

[0024] Figure 6 Normalized elevation difference beam (the thick line in the middle represents the 0-degree azimuth tangent);

[0025] Figure 7 The curves showing the variation of the 1st, 3rd, and 5th order coefficients of the azimuth angle mapping curve with the elevation angle;

[0026] Figure 8 The curves showing the variation of the 1st, 3rd, and 5th order coefficients of the pitch angle angular mapping curve with azimuth angle;

[0027] Figure 9 Two-dimensional angle measurement comparison diagram within 1.5 times the beamwidth of the main lobe (red dot: true position of the target, green * is the traditional angle measurement result, blue ○ is the improved angle measurement result);

[0028] Figure 10 Evaluation of azimuth angle measurement accuracy within 1.5 times the beamwidth of the main lobe (green * represents traditional angle measurement error, blue ○ represents improved angle measurement error);

[0029] Figure 11 Evaluation of pitch dimension angle measurement accuracy within 1.5 times the beamwidth of the main lobe (green * represents traditional angle measurement error, blue ○ represents improved angle measurement error). Detailed Implementation

[0030] The features and advantages of the present invention will become clearer and more apparent from the following detailed description.

[0031] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0032] According to a first aspect of the present invention, a two-dimensional joint angle measurement method based on sum and difference beams is provided, comprising the following steps:

[0033] Establish azimuth and elevation angle measurement mapping relationships, which have two-dimensional coupling characteristics;

[0034] The final azimuth and elevation angles are determined iteratively by using the azimuth and elevation angle mapping relationships.

[0035] Establishment process of angle mapping relationship

[0036] (S1) The antenna patterns of the sum beam, elevation difference beam, and azimuth difference beam of the radar are tested. The antenna patterns of the sum beam, elevation difference beam, and azimuth difference beam are respectively represented as ∑(θAZ θ EL ), Δ EL (θ AZ θ EL ) and Δ AZ (θ AZ θ EL ), where θ AZ and θ EL These are the azimuth and elevation angles, respectively, and the three antenna patterns contain amplitude and phase information.

[0037] (S2) Normalize the two difference beams with respect to the sum beam, i.e., calculate the complex ratio of the elevation difference beam antenna pattern to the sum beam antenna pattern. The complex ratio of the azimuth difference beam pattern to the sum beam pattern

[0038] (S3) for θ EL =-θ 3dB δ θ θ 3dB For each pitch angle position, a 5th-order polynomial was used for fitting. and θ AZ The correspondence between the two is called the azimuth azimuth angle mapping curve, and its polynomial coefficients are expressed as: {p AZ0 (θ EL ), p AZ1 (θ EL ), p AZ2 (θ EL ), p AZ3 (θ EL ), p AZ4 (θ EL ), p AZ5 (θ EL The angle within parentheses in the polynomial coefficients is the pitch angle θ. EL This represents the coefficient p of the azimuth angle mapping curve. AZ0 ~p AZ5 It is a function of the pitch angle. Also known as normalized azimuth difference beam pattern.

[0039] (S4) for θ AZ =-θ 3dB δ θ θ 3dB For each azimuth position, a 5th-order polynomial is used for fitting. and θ EL The correspondence between these two conditions is called the pitch azimuth mapping curve, and its polynomial coefficients are expressed as: {p EL0 (θ AZ ), p EL1 (θ AZ), p EL2 (θ AZ ), p EL3 (θ AZ ), p EL4 (θ AZ ), p EL5 (θ AZ The angles within parentheses in the polynomial coefficients are the azimuth angles θ. AZ This represents the pitch-to-angle mapping curve coefficient p. EL0 ~p EL5 It is a function of azimuth. Also known as normalized pitch difference beam pattern.

[0040] (S5) Fit θ using a second-order polynomial. EL With p AZ1 (θ EL The relationship between ) yields {p AZ1_EL0 p AZ1_EL1 p AZ1_EL2}, Fitting θ EL With p AZ3 (θ EL The relationship between ) yields {p AZ3-EL0 p AZ3_EL1 p AZ3_EL2}, Fitting θ EL With p AZ5 (θ EL The relationship between ) yields {p AZ5_EL0 p AZ5_EL1 p AZ5_EL2}

[0041] (S6) Fit θ using a second-order polynomial respectively. AZ With p EL1 (θ AZ The relationship between ) yields {p EL1_AZ0 p EL1_AZ1 p EL1_AZ2}, Fitting θ AZ With p EL3 (θ AZ The relationship between ) yields {p EL3_AZ0 p EL3_AZ1 p EL3_AZ2}, Fitting θ AZ With p EL5 (θ AZ The relationship between ) yields {p EL5_AZ0 p EL5_AZ1 p EL5_AZ2}

[0042] The azimuth angle measurement mapping relationship, i.e., the first-order term of the azimuth angle measurement coefficient: {p AZ1_EL0 p AZ1_EL1 p AZ1_EL2}, cubic term: {p AZ3_EL0 p AZ3_EL1 p AZ3_EL2} and fifth-order terms: {p AZ5_EL0 p AZ5_EL1 p AZ5_EL2 The coefficients of each order exhibit a quadratic polynomial relationship with the pitch angle.

[0043] The pitch angle mapping relationship, i.e., the first term of the pitch angle coefficient: {p EL1_AZ0 p EL1_AZ1 p EL1_AZ2}, cubic term: {p EL3_AZ0 ;p EL3_AZ1 ;p EL3_AZ2} and fifth-order terms: {p EL5_AZ0 p EL5_AZ1 p EL5_AZ2 The coefficients of each order exhibit a quadratic polynomial relationship with the azimuth angle.

[0044] Before a radar system can perform normal angle measurement, it must obtain the angle measurement coefficients through the methods described above.

[0045] Actual two-dimensional joint angle measurement process of radar

[0046] (S1) and the signals of the elevation difference beam and azimuth difference beam, after matched filtering and accumulation, are represented as s Σ , and

[0047] (S2) Normalize the difference beam signal with respect to the sum beam signal, i.e., calculate and

[0048] (S3) Obtain the initial value of the pitch angle based on the fitting coefficients of the two-dimensional angle measurement mapping curve:

[0049]

[0050] (S4) Obtain the initial azimuth value based on the fitting coefficients of the two-dimensional angle measurement mapping curve:

[0051]

[0052] (S5) Substitute the initial values ​​of the two-dimensional angles into the following iterative equation:

[0053]

[0054]

[0055] (S6) Repeat the iterative equation (S5) 3 to 5 times, then stop the iteration. After the iteration ends... and These are the final elevation and azimuth measurements.

[0056] According to a second aspect of the present invention, a two-dimensional joint angle measuring device based on sum and difference beams is provided, comprising:

[0057] The first module is used to establish azimuth and elevation angle measurement mapping relationships;

[0058] The second module is used to iteratively determine the final azimuth and elevation angles by utilizing the azimuth and elevation angle mapping relationships.

[0059] According to a third aspect of the present invention, a two-dimensional joint angle measuring device based on sum and difference beams is provided, comprising:

[0060] One or more processors;

[0061] Storage device for storing one or more programs.

[0062] When the one or more programs are executed by the one or more processors, the one or more processors implement the two-dimensional joint angle measurement method based on sum and difference beams as described in the first aspect.

[0063] According to a fourth aspect of the invention, a readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the two-dimensional joint angle measurement method based on sum-difference beams as described in the first aspect.

[0064] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the devices, equipment, and execution units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0065] Example

[0066] The above methods were verified using the simulation data shown in Table 1.

[0067] Table 1. Parameters for Two-Dimensional Angle Measurement Simulation Verification

[0068] Pitch beamwidth 2 degrees Azimuth beamwidth 2 degrees Amplitude-to-angle measurement evaluation range 1.5 times beamwidth (2D)

[0069] The simulated antenna pattern is as follows Figures 2-4 The figures shown are the radiation patterns of a two-dimensional antenna for the sum beam, azimuth difference beam, and elevation difference beam, respectively. By comparing the amplitudes of the azimuth difference beam and the sum beam, the following can be obtained: Figure 5The results shown are actually performed within the main lobe, therefore only results within ±1.5 degrees are displayed. As can be seen from the surface in the figure, the azimuth ratio amplitude mainly varies with the azimuth angle, but also varies to some extent with the elevation angle. Traditional angle measurement methods only fit the curve (red line) at the 0-degree elevation angle to obtain the azimuth angle measurement mapping curve. Figure 6 The amplitude comparison surface of the elevation difference beam and the sum beam shows that the elevation amplitude comparison mainly varies with the elevation angle, but also varies to some extent with the azimuth angle. Traditional angle measurement methods only fit the curve (red line) at the 0-degree azimuth angle to obtain the elevation angle measurement mapping curve. Therefore, traditional angle measurement methods ignore the two-dimensional variation characteristics of the amplitude comparison and only consider the one-dimensional variation characteristics, which inherently introduces measurement errors.

[0070] Figure 5 and Figure 6 The red line in the diagram is represented in an odd symmetric form, which can be accurately fitted using a 5th-order polynomial. The one-dimensional representation of the vertical red line is primarily a quadratic curve. Through... Figure 5 Fifth-order polynomial fitting was performed on the angle measurement curves of different elevation sections to obtain the variation of each order coefficient with the elevation angle. Then, second-order polynomial fitting was performed to obtain the azimuth angle measurement mapping curve, and the curves of each order coefficient with the elevation angle are shown below. Figure 7 As shown. Similarly, the curves showing the variation of each order coefficient of the pitch angle mapping curve with the azimuth angle are obtained as follows. Figure 8 As shown. Since the even-order coefficients in the 5th-order polynomial are very small, they are ignored in actual fitting. Figure 7 and Figure 8 Not displayed.

[0071] Within a range of ±1.5 degrees, targets are uniformly distributed at 0.15-degree intervals, and a traditional angle measurement method is used (using... Figure 5 and Figure 6 Angle measurement simulations were performed using the red angle measurement curve (in the image) and the improved angle measurement method. The simulation results are as follows: Figure 9 As shown, the improved angle measurement accuracy is significantly better than the traditional method, especially in locations away from the beam center. The traditional method has high azimuth accuracy near the 0-degree elevation plane and high elevation accuracy near the 0-degree azimuth plane, approaching that of the improved method. This is because the traditional angle measurement mapping curves are established separately on the 0-elevation and 0-azimuth planes. The improved method, however, maintains high angle measurement accuracy throughout the entire two-dimensional main lobe, demonstrating a significant improvement in accuracy.

[0072] To further quantitatively evaluate the accuracy of the two angle measurement methods Figure 10 The variation law of azimuth angle measurement accuracy in the two-dimensional angle plane is given. Figure 11The variation law of elevation angle measurement accuracy in the two-dimensional angle plane is presented. As shown in the table below:

[0073] Table 2. Accuracy Evaluation of Two Angle Measurement Methods

[0074] Angle measurement method Azimuth angle measurement accuracy Pitch angle measurement accuracy Traditional angle measurement methods ±0.11 degrees ±0.15 degrees Improved angle measurement method ±0.02 degrees ±0.02 degrees

[0075] The above accuracy is related to the beamwidth and is the result of an accuracy assessment conducted within 1.5 times the main lobe.

[0076] The two-dimensional joint angle measurement method based on sum and difference beams proposed in this invention overcomes the problem of large measurement errors at non-0-degree sectional positions in traditional angle measurement. It employs a second-order polynomial to describe the variation of the angle measurement curve coefficients with the other dimension angle, and converges with only a few iterations, resulting in a low computational load. Based on relevant domestic and international literature on target angle measurement methods for tracking radar, the innovation of this invention lies in:

[0077] (1) The angle measurement model takes into account the two-dimensional coupling characteristics, which is more in line with the actual variation law of the sum and difference ratio.

[0078] (2) The algorithm uses a polynomial fitting method, which requires fewer parameters. By using simple polynomial calculations and combining a small number of iterations, relatively accurate two-dimensional angle measurement results can be obtained, which has strong engineering feasibility.

[0079] (3) It does not require increasing the cost of radar hardware, significantly improves the accuracy of angle measurement, and has great application potential in target tracking radar.

[0080] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0081] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A two-dimensional joint angle measurement method based on sum and difference beams, characterized in that, Includes the following steps: Establish azimuth and elevation angle measurement mapping relationships; The final azimuth and elevation angles are determined iteratively using the azimuth and elevation angle mapping relationships. The steps for establishing the azimuth and elevation angle mapping relationships are implemented in the following manner: (S1) The antenna patterns of the sum beam, elevation difference beam, and azimuth difference beam of the radar are tested. The antenna patterns of the sum beam, elevation difference beam, and azimuth difference beam are represented as Σ(θ) AZ ,θ EL ), Δ EL (θ AZ ,θ EL ) and Δ AZ (θ AZ ,θ EL ), where θ AZ and θ EL These are the azimuth and elevation angles, respectively. (S2) Normalize the two difference beams with respect to the sum beam, i.e., determine the complex ratio between the elevation difference beam antenna pattern and the sum beam antenna pattern. The complex ratio of the azimuth difference beam pattern to the sum beam pattern (S3) for θ EL =-θ 3dB :δ θ :θ 3dB For each pitch angle position, a 5th-order polynomial was used for fitting. and θ AZ The correspondence between the two is called the azimuth azimuth angle mapping curve, and its polynomial coefficients are expressed as: {p AZ0 (θ EL ),p AZ1 (θ EL ),p AZ2 (θ EL ),p AZ3 (θ EL ),p AZ4 (θ EL ),p AZ5 (θ EL The angle within parentheses in the polynomial coefficients is the pitch angle θ. EL This represents the coefficient p of the azimuth angle mapping curve. AZ0 ~p AZ5 It is a function of the pitch angle. This is the normalized azimuth difference beam pattern; (S4) for θ AZ =-θ 3dB :δ θ :θ 3dB For each azimuth position, a 5th-order polynomial is used for fitting. and θ EL The correspondence between these two conditions is called the pitch azimuth mapping curve, and its polynomial coefficients are expressed as: {p EL0 (θ AZ ),p EL1 (θ AZ ),p EL2 (θ AZ ),p EL3 (θ AZ ),p EL4 (θ AZ ),p EL5 (θ AZ The angles within parentheses in the polynomial coefficients are the azimuth angles θ. AZ This represents the pitch-to-angle mapping curve coefficient p. EL0 ~p EL5 It is a function of azimuth. Normalized elevation difference beam pattern; (S5) Fit θ using a second-order polynomial. EL With p AZ1 (θ EL The relationship between ) yields {p AZ1_EL0 p AZ1_EL1 p AZ1_EL2 }, Fitting pitch angle θ EL With p AZ3 (θ EL The relationship between ) yields {p AZ3_EL0 p AZ3_EL1 ,p AZ3_EL2 }, Fitting θ EL With p AZ5 (θ EL The relationship between ) yields {p AZ5_EL0 p AZ5_EL1 p AZ5_EL2 }; (S6) Fit θ using a second-order polynomial respectively. AZ With p EL1 (θ AZ The relationship between ) yields {p EL1_AZ0 p EL1_AZ1 p EL1_AZ2 }, Fitting azimuth angle θ AZ With p EL3 (θ AZ The relationship between ) yields {p EL3_AZ0 p EL3_AZ1 p EL3_AZ2 }, Fitting θ AZ With p EL5 (θ AZ The relationship between ) yields {p EL5_AZ0 p EL5_AZ1 p EL5_AZ2 }; The azimuth angle measurement mapping relationship, i.e., the first-order term of the azimuth angle measurement coefficient: {p AZ1_EL0 p AZ1_EL1 p AZ1_EL2 }, cubic term: {p AZ3_EL0 p AZ3_EL1 p AZ3_EL2 } and fifth-order terms: {p AZ5_EL0 p AZ5_EL1 p AZ5_EL2 Each order coefficient exhibits a quadratic polynomial relationship with the pitch angle; The pitch angle mapping relationship, i.e., the first term of the pitch angle coefficient: {p EL1_AZ0 p EL1_AZ1 p EL1_AZ2 }, cubic term: {p EL3_AZ0 p EL3_AZ1 p EL3_AZ2 } and fifth-order terms: {p EL5_AZ0 p EL5_AZ1 p EL5_AZ2 The coefficients of each order exhibit a quadratic polynomial relationship with the azimuth angle.

2. The two-dimensional joint angle measurement method based on sum and difference beams according to claim 1, characterized in that, The step of iteratively determining the final azimuth and elevation angles using the azimuth and elevation angle mapping relationships is implemented in the following manner: (S1) and the signals of the elevation difference beam and azimuth difference beam, after matched filtering and accumulation, are represented as s ∑ , and (S2) Normalize the difference beam signal with respect to the sum beam signal, i.e., determine and (S3) Obtain the initial value of the pitch angle based on the fitting coefficients of the two-dimensional angle measurement mapping curve: (S4) Obtain the initial azimuth value based on the fitting coefficients of the two-dimensional angle measurement mapping curve: (S5) Substitute the initial values ​​of the two-dimensional angles into the following iterative equation: (S6) Repeat the iterative equation (S5) 3 to 5 times, then stop the iteration. After the iteration ends... and These are the final elevation and azimuth measurements.

3. A two-dimensional joint angle measurement device based on sum and difference beams, characterized in that, include: The first module is used to establish azimuth and elevation angle measurement mapping relationships; The second module is used to iteratively determine the final azimuth and elevation angles using the azimuth and elevation angle mapping relationships. The first module establishes the azimuth and elevation angle measurement mapping relationships in the following manner: (S1) The antenna patterns of the sum beam, elevation difference beam, and azimuth difference beam of the radar are tested. The antenna patterns of the sum beam, elevation difference beam, and azimuth difference beam are represented as Σ(θ) AZ ,θ EL ), Δ EL (θ AZ ,θ EL ) and Δ AZ (θ AZ ,θ EL ), where θ AZ and θ EL These are the azimuth and elevation angles, respectively. (S2) Normalize the two difference beams with respect to the sum beam, i.e., determine the complex ratio between the elevation difference beam antenna pattern and the sum beam antenna pattern. The complex ratio of the azimuth difference beam pattern to the sum beam pattern (S3) for θ EL =-θ 3dB :δ θ :θ 3dB For each pitch angle position, a 5th-order polynomial was used for fitting. and θ AZ The correspondence between the two is called the azimuth azimuth angle mapping curve, and its polynomial coefficients are expressed as: {p AZ0 (θ EL ), p AZ1 (θ EL ), p AZ2 (θ EL ), p AZ3 (θ EL ), p AZ4 (θ EL ), p AZ5 (θ EL The angle within parentheses in the polynomial coefficients is the pitch angle θ. EL This represents the coefficient p of the azimuth angle mapping curve. AZ0 ~p AZ5 It is a function of the pitch angle. This is the normalized azimuth difference beam pattern; (S4) for θ AZ =-θ 3dB δ θ θ 3dB For each azimuth position, a 5th-order polynomial is used for fitting. and θ EL The correspondence between these two conditions is called the pitch azimuth mapping curve, and its polynomial coefficients are expressed as: {p EL0 (θ AZ ), p EL1 (θ AZ ), p EL2 (θ AZ ), p EL3 (θ AZ )p EL4 (θ AZ ), p EL5 (θ AZ The angles within parentheses in the polynomial coefficients are the azimuth angles θ. AZ This represents the pitch-to-angle mapping curve coefficient p. EL0 ~p EL5 It is a function of azimuth. Normalized elevation difference beam pattern; (S5) Fit θ using a second-order polynomial. EL With p AZ1 (θ EL The relationship between ) yields {p AZ1_EL0 p AZ1_EL1 p AZ1_EL2 }, Fitting pitch angle θ EL With p AZ3 (θ EL The relationship between ) yields {p AZ3_EL0 p AZ3_EL1 p AZ3_EL2 }, Fitting θ EL With p AZ5 (θ EL The relationship between ) yields {p AZ5_EL0 p AZ5_EL1 p AZ5_EL2 }; (S6) Fit θ using a second-order polynomial respectively. AZ With p EL1 (θ AZ The relationship between ) yields {p EL1_AZ0 p EL1_AZ1 p EL1_AZ2 }, Fitting azimuth angle θ AZ With p EL3 (θ AZ The relationship between ) yields {p EL3_AZ0 p EL3_AZ1 p EL3_AZ2 }, Fitting θ AZ With p EL5 (θ AZ The relationship between ) yields {p EL5_AZ0 p EL5_AZ1 p EL5_AZ2 }; The azimuth angle measurement mapping relationship, i.e., the first-order term of the azimuth angle measurement coefficient: {p AZ1_EL0 p AZ1_EL1 p AZ1_EL2 }, cubic term: {p AZ3_EL0 p AZ3_EL1 p AZ3_EL2 } and fifth-order terms: {p AZ5_EL0 p AZ5_EL1 ,p AZ5_EL2 Each order coefficient exhibits a quadratic polynomial relationship with the pitch angle; The pitch angle mapping relationship, i.e., the first term of the pitch angle coefficient: {p EL1_AZ0 p EL1_AZ1 p EL1_AZ2 }, cubic term: {p EL3_AZ0 p EL3_AZ1 p EL3_AZ2 } and fifth-order terms: {p EL5_AZ0 p EL5_AZ1 p EL5_AZ2 The coefficients of each order exhibit a quadratic polynomial relationship with the azimuth angle.

4. The two-dimensional joint angle measuring device based on sum and difference beams according to claim 3, characterized in that, The second module determines the final azimuth and elevation angles in the following manner: (S1) and the signals of the elevation difference beam and azimuth difference beam, after matched filtering and accumulation, are represented as s ∑ , and (S2) Normalize the difference beam signal with respect to the sum beam signal, i.e., determine and (S3) Obtain the initial value of the pitch angle based on the fitting coefficients of the two-dimensional angle measurement mapping curve: (S4) Obtain the initial azimuth value based on the fitting coefficients of the two-dimensional angle measurement mapping curve: (S5) Substitute the initial values ​​of the two-dimensional angles into the following iterative equation: (S6) Repeat the iterative equation (S5) 3 to 5 times, then stop the iteration. After the iteration ends... and These are the final elevation and azimuth measurements.

5. A two-dimensional joint angle measuring device based on sum and difference beams, characterized in that, include: One or more processors; Storage device for storing one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the two-dimensional joint angle measurement method based on sum and difference beams as described in claim 1 or 2.

6. A readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the two-dimensional joint angle measurement method based on sum and difference beams as described in claim 1 or 2.

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