Sum-difference beam division method based on conformal array antenna, storage medium and electronic equipment

Abstract

The invention discloses a sum-difference beam division method based on a conformal array antenna, a storage medium and electronic equipment, and the method comprises the following steps: building a coordinate system: building an array plane coordinate and an auxiliary coordinate, and enabling the direction of arrival to be parallel to the X0 axis of the auxiliary coordinate system; coordinate conversion: converting the coordinates of the antenna units in the array plane coordinate system into the coordinates of an auxiliary coordinate system; calculating the included angle between the incoming wave and the normal of the antenna unit, and judging whether the antenna unit is an antenna unit working effectively or not; after the coordinates are translated, a new coordinate plane and new coordinates of the antenna units which work effectively and are projected to the new coordinate plane are obtained; appropriate optimization is carried out by referring to a planar array half-array method, and finally a sum and difference beam of a conformal array is extracted. According to the method, all effective antenna units participate in sum-difference beam division as much as possible, so that the receiving gain of the conformal array antenna is ensured, the zero value depth of the difference beam is fully considered, and the angle measurement precision is ensured. According to the method, huge workload caused by a table look-up method can be avoided, the operation efficiency is high, and the engineering practicability is high.

Description

Technical Field

[0001] This invention relates to the field of conformal array antenna technology, and more particularly to a sum and difference beamforming method, storage medium, and electronic device based on a conformal array antenna. Background Technology

[0002] Currently, conformal array antennas are array antennas in which radiating elements are arranged on a specified curve or surface. Conformal array antennas have multi-target, full-airspace coverage capabilities. Due to their conformal design with the carrier, they have the advantage of not disrupting the aerodynamic parameters of the aircraft. As ground equipment, they also have advantages such as resistance to harsh weather conditions, resistance to mechanical vibration, and ease of camouflage.

[0003] Common conformal array antennas include ring arrays, circular arrays, conical arrays, cylindrical arrays, and spherical arrays. They are constructed by arranging radiating elements on a circle, a circular surface, a conical surface, a cylindrical surface, or a spherical surface, respectively. Among them, cylindrical arrays can achieve wide-angle scanning in one-dimensional space, while spherical arrays can achieve scanning in hemispherical spatial domains.

[0004] For phased array antennas, monopulse angle measurement is a widely used technique. Monopulse angle measurement mainly includes two methods: sum-difference amplitude comparison and sum-difference phase comparison. Sum-difference amplitude comparison does not have strict requirements on the symmetry of the array element distribution, making it particularly suitable for conformal array antennas with asymmetric designs. A crucial step in using sum-difference amplitude comparison angle measurement is identifying the sum beam and dividing the azimuth difference (+), azimuth difference (-), elevation difference (+), and elevation difference (-). For planar array antennas, a half-array method is typically used for sum-difference beam division, but this is not directly applicable to three-dimensional conformal arrays. Furthermore, traditional sum-difference direction finding mostly involves pre-calculating the angle values ​​for each azimuth and elevation input through simulation, forming an angle table, and storing it in Flash memory. During program execution, the angle table is queried based on the target azimuth and elevation to obtain the estimated direction of arrival. Calculating with azimuth 0–360°, elevation 0–90°, and increments of 0.1°, the amount of angle table data required is extremely large, resulting in a correspondingly large workload for preliminary simulation calculations and data processing. Reducing the step value and thus the amount of data in the angle table can significantly reduce the workload, but at the cost of measurement accuracy, so it is difficult to have the best of both worlds. Summary of the Invention

[0005] The purpose of this invention is to provide a sum and difference beamforming method, storage medium, and electronic device based on a conformal array antenna, which can ensure accuracy while greatly reducing data processing volume and improving efficiency.

[0006] The technical solution adopted in this invention is as follows:

[0007] A sum-difference beamforming method based on a conformal array antenna, wherein the conformal array antenna is composed of a cylindrical array and a spherical array disposed on the cylindrical array, and multiple layers of antenna elements are disposed on the conformal array antenna, with each layer of antenna elements uniformly disposed on the corresponding cylindrical or spherical array; the method includes the following steps:

[0008] A: Establishment of coordinate systems: Establish the frontal coordinate system OXYZ and the auxiliary coordinate system OX0Y0Z0, where the direction of incoming waves is parallel to the X0 axis of the auxiliary coordinate system;

[0009] B: Coordinate transformation, converting the coordinates of the antenna element in the array coordinate system to the coordinates in the auxiliary coordinate system;

[0010] C: Calculate the angle between the incoming wave and the normal to the antenna element;

[0011] D: Compare the angle between the obtained incoming wave and the antenna element normal with the set maximum incident angle. If the angle between the incoming wave and the antenna element normal is less than or equal to the maximum incident angle, the antenna element is determined to be a working antenna element; otherwise, it is determined to be an invalid antenna element.

[0012] E: Coordinate translation, the amount of translation along the Y0 coordinate axis calculated based on the sum of the antenna gains of all effectively operating antenna elements in the conformal array. y0 and the translation Trans on the Z0 coordinate axis z0 After obtaining the new coordinate plane OY1Z1, the new coordinates of the effectively working antenna element projected onto the coordinate plane OY1Z1 can be obtained, denoted as (y i1 ,z i1 );

[0013] F: By appropriately optimizing the planar array half-array method, the sum and difference beams of the conformal array are finally extracted.

[0014] In step A, the azimuth angle of the incoming wave is denoted as... If the pitch angle is θ, then the auxiliary coordinate system OX0Y0Z0 rotates counterclockwise by θ around the Y0 axis and then clockwise around the Z0 axis. Afterwards, it coincides with the array coordinate system OXYZ. According to the rotation relationship, the auxiliary coordinate system Y0 axis is coplanar with OXY, and the array coordinate system Z axis is coplanar with OX0Z0.

[0015] Step B specifically includes the following steps:

[0016] The transformation matrix from the auxiliary coordinate system OX0Y0Z0 to the frontal coordinate system OXYZ is:

[0017] The array coordinate system OXYZ rotates counterclockwise around the Z-axis. Then, after rotating clockwise by θ around the Y-axis, it coincides with the auxiliary coordinate system OX0Y0Z0. The transformation matrix from the frontal coordinate system OXYZ to the auxiliary coordinate system OX0Y0Z0 is:

[0018] Let the coordinates of antenna element i in the array coordinate system OXYZ be... The coordinates transformed to the auxiliary coordinate system OX0Y0Z0 are:

[0019]

[0020] Step C specifically includes the following steps: Given the azimuth angle of the incoming wave as... The elevation angle is θ, and in the coordinate system OXYZ, the direction of the incoming wave is equivalent to a vector (x, y, z), where... z = sinθ; the normal vector of antenna element i is (x′ i ,y′ i ,z′ i If the direction of the incoming wave is Δ, then the angle Δ between the direction of the incoming wave and the normal of antenna element i is... i for:

[0021]

[0022] Step E specifically includes the following steps:

[0023] E1: Project the effectively working antenna element i onto the OY0Z0 plane, that is, its coordinates on the OY0Z0 plane are (y io ,z i0 E2: Based on the angle Δ between the normal of antenna element i and the incoming wave. i Find the antenna gain G by looking up the table. i ;

[0024] E3: Sum the antenna gains of all effectively working antenna elements to obtain the summed gain G. sum ;

[0025] E4: Set the coordinate values ​​of each antenna y io With antenna gain G i Multiply and then sum to get the sum Sum y*g ;

[0026] E5: Set the coordinate values ​​of each antenna z io With antenna gain G i Multiply and then sum to get the sum Sum z*g ;

[0027] E6: Sum y*g Divide by G sum The translation amount Trans on the Y0 coordinate axis is obtained.y0 ;

[0028] E7: Sum z*g Divide by G sum The translation amount Trans on the Z0 coordinate axis is obtained. z0 ;

[0029] E8: Translate the coordinate plane OY0Z0 along the Y0 coordinate axis. y0 Then translate along the Z0 coordinate axis Trans z0 The new coordinate plane OY1Z1 is obtained, and the coordinates of antenna element i projected onto coordinate plane OY1Z1 are (y i1 ,z i1 ),in:

[0030] y i1 =y i0 -Trans y0 Equation (5)

[0031] z i1 =z i0 -Trans z0 Equation (6)

[0032] Step F specifically includes the following steps:

[0033] F1: Beam determination: All units determined to be working are set to beam;

[0034] F2: Azimuth difference beam determination: setting the threshold thr y This threshold is a small positive number, which can be determined based on specific antenna deployment and simulation results; for the effective working unit projected onto the coordinate plane OY1Z1, when y i1 >thr y When y is positive, the antenna element is determined to have an azimuth difference of +; when y is negative, the antenna element i1 <-thr y At that time, the antenna element is determined to have an azimuth difference of -.

[0035] F3: Determining the pitch difference beam: Setting the threshold thr z This threshold is a small positive number, which can be determined based on specific antenna deployment and simulation results; for effective working units projected onto the coordinate plane OY1Z1, when z i1 >thr z When z is positive, the unit is determined to be pitch difference +; when z is negative, the pitch difference is +. i1 <-thr z At that time, the unit was determined to be pitch difference -.

[0036] A computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the device on which the computer-readable storage medium is located performs the sum and difference beam division method based on a conformal array antenna.

[0037] An electronic device includes a memory and a processor, wherein the memory stores a program executable on the processor, and the processor executes the program to implement the sum and difference beamforming method based on a conformal array antenna.

[0038] This invention first calculates the angle between the incoming wave direction vector and the normal vector of each antenna element, and determines the effective working antenna elements based on the angle. Then, it transforms the original antenna coordinate system OXYZ to a new coordinate system OX0Y0Z0, and projects the effective working antenna elements onto the new coordinate plane OY0Z0. Based on the projection of the antenna elements onto the coordinate plane OY0Z0, the angle between the antenna element normal vector and the incoming wave, and the antenna pattern, a set of offset data is obtained using a specific algorithm. This offset data is then used to translate the coordinate plane OY0Z0 again to obtain a new coordinate plane OY1Z1. Finally, on the coordinate plane OY1Z1, appropriate optimization is performed using a planar array half-array method to extract the sum and difference beams of the conformal array. This invention strives to involve all effective antenna elements in the sum and difference beam division to ensure the receiving gain of the conformal array antenna, while also fully considering the zero-value depth of the difference beam to guarantee angle measurement accuracy. This invention avoids the massive workload of lookup table methods, offering high computational efficiency and strong engineering practicality. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art 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.

[0040] Figure 1 This is a flowchart of the present invention;

[0041] Figure 2 This is a schematic diagram of the array surface coordinate system and auxiliary coordinate system described in this invention;

[0042] Figure 3 This is a schematic diagram of the OY1Z1 planar sum and difference beam division described in this invention;

[0043] Figure 4 This is a flowchart of the software processing described in this invention;

[0044] Figure 5 This is a software relationship diagram illustrating the direction finding and target tracking described in this invention.

[0045] Figure 6 This is a schematic diagram of the projection and coordinate translation of the effective antenna element described in this invention;

[0046] Figure 7 This is a schematic diagram of the antenna simulation results described in this invention. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] like Figure 1 , 2 As shown in Figure 3, the conformal array antenna of the present invention consists of a cylindrical array and a spherical array, which can achieve an array beam angle coverage of azimuth 0–360° and elevation 0–90°. This conformal array design comprises 7 layers and a total of 64 antenna elements, with each element arranged relatively evenly on the cylindrical and spherical arrays according to a certain pattern.

[0049] This method aims to involve all effective antenna elements in sum-difference beamforming to ensure the receiving gain of the conformal array antenna while also taking into account the null depth of the difference beam to guarantee angle measurement accuracy. This sum-difference beamforming method avoids the massive workload associated with table lookup methods, offering high computational efficiency and strong engineering practicality. The specific steps include:

[0050] Step A: Establishing the Coordinate System: Establish the array coordinate system OXYZ and the auxiliary coordinate system OX0Y0Z0, where the incoming wave direction is parallel to the X0 axis of the auxiliary coordinate system. The array coordinate system and the auxiliary coordinate system are as follows: Figure 2 As shown, the azimuth angle of the incoming wave is The pitch angle is θ.

[0051] The auxiliary coordinate system OX0Y0Z0 is rotated counterclockwise by θ around the Y0 axis, and then clockwise around the Z0 axis. Then, it coincides with the array coordinate system OXYZ. According to the rotation relationship, the auxiliary coordinate system Y0 axis is coplanar with OXY, and the array coordinate system Z axis is coplanar with OX0Z0.

[0052] Step B: Coordinate Transformation: The transformation matrix from the auxiliary coordinate system OX0Y0Z0 to the frontal coordinate system OXYZ is:

[0053]

[0054] The array coordinate system OXYZ rotates counterclockwise around the Z-axis. Then, after rotating clockwise by θ around the Y-axis, it coincides with the auxiliary coordinate system OX0Y0Z0. The transformation matrix from the frontal coordinate system OXYZ to the auxiliary coordinate system OX0Y0Z0 is:

[0055]

[0056] Let the coordinates of antenna element i in the array coordinate system OXYZ be... The coordinates transformed to the auxiliary coordinate system OX0Y0Z0 are:

[0057]

[0058] Step C: Calculate the angle between the incoming wave and the antenna element normal.

[0059] Given the azimuth angle of the incoming wave is The elevation angle is θ, and in the coordinate system OXYZ, the direction of the incoming wave is equivalent to a vector (x, y, z), where... z = sinθ. The normal vector of antenna element i is (x′ i ,y′ i ,z′ i If the direction of the incoming wave is Δ, then the angle Δ between the direction of the incoming wave and the normal of antenna element i is... i for:

[0060]

[0061] Step D: Valid cell determination:

[0062] Based on the antenna element design, determine the maximum incident angle Δ max According to the pattern product theorem, within the visible range, effective cells must be selected to maximize the main lobe gain. However, an excessively large angle will result in a large grating lobe, thus requiring a comprehensive consideration. This invention determines the maximum incident angle Δ. max The method is as follows: antenna simulation is performed with a beamwidth of 3dB to 6dB to generate beam patterns corresponding to each beamwidth under typical incoming wave directions. The best simulated beamwidth is then selected as the maximum incident angle Δ. max The selection principle requires a comprehensive consideration of the main lobe and grating lobe gains; high main lobe gain and low grating lobe gain yield the best results. When the angle Δ between the direction of the incoming wave and the normal to the antenna element is... i Less than or equal to the maximum incident angle Δ max If the condition is met, the antenna element can be determined as a valid working element; otherwise, it is determined as an invalid working element.

[0063] Step E: Coordinate Translation

[0064] (1) Project the effectively working antenna element i onto the OY0Z0 plane, that is, the coordinates of i on the OY0Z0 plane are (y io ,zi0 );

[0065] (2) Based on the angle Δ between the normal of antenna element i and the incoming wave. i Find the antenna gain G by looking up the table. i ;

[0066] (3) Sum the antenna gains of all the working antenna elements to obtain the summed gain G. sum ;

[0067] (4) Set the coordinate values ​​of each antenna y io With antenna gain G i Multiply and then sum to get the sum Sum y*g ;

[0068] (5) Set the coordinate values ​​z of each antenna io With antenna gain G i Multiply and then sum to get the sum Sum z*g ;

[0069] (6) Sum y*g Divide by G sum The translation amount Trans on the Y0 coordinate axis is obtained. y0 ;

[0070] (7) Sum z*g Divide by G sum The translation amount Trans on the Z0 coordinate axis is obtained. z0 ;

[0071] (8) Translate the coordinate plane OY0Z0 along the Y0 coordinate axis. y0 Then translate along the Z0 coordinate axis Trans z0 The new coordinate plane OY1Z1 is obtained, and the coordinates of antenna element i projected onto coordinate plane OY1Z1 are (y i1 ,z i1 ),in:

[0072] y i1 =y i0 -Trans y0 Equation (5)

[0073] z i1 =z i0 -Trans z0 Equation (6)

[0074] Step F: Determining the sum and difference beam

[0075] Planar arrays already consider element symmetry in their design; therefore, the half-array method directly divides the elements into four quadrants: quadrants 1 and 2 represent elevation difference +; quadrants 3 and 4 represent elevation difference -; quadrants 1 and 4 represent azimuth difference +; and quadrants 2 and 3 represent azimuth difference -. However, in a conformal array, most of the antenna elements that are effectively operating, after being projected onto the coordinate plane OY1Z1, lack symmetry. Elements close to the coordinate axes are actually in an unstable state of difference beam + and difference beam -, and can be eliminated from difference beam division. Therefore, by referring to the planar array half-array method and performing appropriate optimization, the sum and difference beams of the conformal array are finally extracted.

[0076] (1) and beam determination

[0077] All antenna elements deemed to be functional are configured with a beam.

[0078] (2) Determination of azimuth difference beam

[0079] Set threshold thr y This threshold is a small positive number and can be determined based on specific antenna deployment and simulation results. For an effective working antenna element projected onto the coordinate plane OY1Z1, when y i1 >thr y When y is positive, the antenna element is determined to have an azimuth difference of +; when y is negative, the antenna element i1 <-thr y At that time, the antenna element is determined to have an azimuth error of -1. Threshold thr y Its function is to eliminate antenna elements near the OZ1 axis. These antenna elements are in an unstable state where the azimuth difference + and azimuth difference - jumps, and can be eliminated because they do not participate in the division of the azimuth difference beam.

[0080] (3) Determination of pitch difference beam

[0081] Set threshold thr z This threshold is a small positive number and can be determined based on specific antenna deployment and simulation results. For an effective working antenna element projected onto the coordinate plane OY1Z1, when z i1 >thr z When z is positive, the antenna element is determined to have an elevation difference of +; when z is negative, the antenna element is determined to have an i1 <-thr z At that time, the antenna element is determined to have an elevation difference of -. Threshold thr z The purpose is to eliminate antenna elements near the OY1 axis, as these elements are in an unstable state with pitch difference + and pitch difference - jumps, and thus do not participate in pitch difference beam division. In the OY1Z1 plane, the sum and difference beam division is as follows: Figure 3 As shown.

[0082] This invention generates sum and difference beams for each azimuth and elevation using the above algorithm, and then selects a subset of typical incident angles for simulation verification to ensure that the difference beam effect meets the angle measurement requirements. For intervals with unsatisfactory results, adjustments and optimizations can be made individually and stored in Flash memory. The program can then directly extract the beams by indexing the azimuth and elevation inputs. By combining the algorithm with a local optimization strategy, a conformal array sum and difference beam extraction method that is practical for engineering applications is achieved. The specific software processing flow is as follows: Figure 4 As shown, the general steps are as follows: hardware initialization, parameter initialization, input of receiving azimuth and elevation information; then, based on the above receiving azimuth and elevation information, calculate the coordinate transformation matrix, perform coordinate transformation, then calculate the angle between the incoming wave and the antenna element normal, and determine the effective antenna elements; the obtained effective antenna elements participate in the calculation of coordinate translation, then perform coordinate translation, and finally perform sum and difference beam division and extraction, and finally calculate the amplitude and phase weights, and finally output the sum and difference beam division and amplitude and phase weights. Repeat the above steps to operate on each antenna element to complete the overall division and amplitude and phase weight output.

[0083] Figure 4 The amplitude and phase weight calculation described herein refers to calculating the amplitude and phase weights corresponding to each beam based on the direction and frequency of arrival. After completing the sum and difference beam division and weight calculation, the division results and corresponding amplitude and phase weights are sent to the FPGA for digital beamforming and baseband signal processing, ultimately realizing the extraction of angular errors. Under the closed-loop control of the beam control software, multi-target direction finding and tracking are achieved. The software relationship for realizing direction finding and target tracking described in this invention is as follows: Figure 5 As shown, this is a process for subsequent application and is not the core inventive point of this invention.

[0084] It should be noted that the azimuth and elevation difference beams in this invention are formed in the OX1Y1Z1 coordinate system. After receiving the azimuth and elevation errors sent by the FPGA, the beam control software needs to convert them to the array plane coordinate system OXYZ before performing closed-loop control. The derivation process is as follows: 1. Convert the azimuth error in the OX1Y1Z1 coordinate system... 1. Convert the pitch angle error Δθ1 into a unit vector ν1; 2. Transform vector ν1 into the OXYZ coordinate system using the rotation matrix C (Equation 1) to obtain vector ν; 3. Transform vector ν into the azimuth angle in the OXYZ coordinate system. and pitch angle θ * .

[0085] The formula is as follows:

[0086]

[0087] Based on the defined ranges of azimuth and elevation, special handling of the inverse trigonometric function quadrant in the above formula is required during software implementation. The azimuth angle in the OXYZ coordinate system is calculated using the above formula. and pitch angle θ * Then, the azimuth error in the OXYZ coordinate system can be obtained. The pitch angle error Δθ is as follows:

[0088]

[0089] Δθ=θ * -θ

[0090] Wave control software according to By using closed-loop control with Δθ, direction finding and tracking of multiple targets can be achieved.

[0091] This invention achieves sum and difference beamforming through software algorithms, avoiding the cumbersome table creation process and making it suitable for angle measurement of small- to medium-scale conformal array antennas. Specifically, in practical applications, beamforming and weight calculation software can be developed on the Xilinx Zynq7 series hardware platform. This software implements the sum and difference beamforming of the conformal array antenna described in the solution, as well as the calculation of the amplitude and phase weights of the corresponding beams. The weight calculation results and sum and difference beamforming results are then sent to the FPGA for digital beamforming.

[0092] To test the software's processing performance, the target azimuth and elevation were periodically sent to the beamforming and weighting software via the network port at a period of 1ms, with 10 targets being sent simultaneously. The test showed that the beamforming and weighting software could respond and complete the processing in real time, meaning that the sum-difference beamforming method (which actually includes amplitude and phase weighting calculation) has the real-time processing capability for 10 targets at 1000Hz.

[0093] To verify the effectiveness of the algorithm, sum and difference beamforming results were generated for each orientation and elevation input based on the described sum and difference beamforming method. The results were then verified through antenna simulation. Figure 6 The above describes the software processing results for beamforming and weight calculation under a typical input. The figure shows the projection and coordinate translation of the effective elements in the OY1Z1 plane. Figure 7 The corresponding antenna simulation results are shown. The green curve in the antenna simulation results graph represents the radiation pattern calculated using the difference beam extracted according to the algorithm described in this invention.

[0094] Experimental results show that after the effective elements are projected and translated onto the OY1Z1 plane, the OY1 and OZ1 axes divide the distribution of effective elements in a relatively balanced manner. This sum-difference beamforming method effectively ensures the beamforming gain and also has a good difference null depth. However, as the elevation value increases, the difference beam null depth gradually decreases, but this phenomenon is mainly caused by the inherent design of the conformal array antenna and is difficult to eliminate by the algorithm itself.

[0095] Simulation results show that this sum-difference beamforming method ensures that the effective antenna elements participate in beamforming to the maximum extent, effectively guaranteeing the beamforming gain; ineffective elements do not participate in beamforming, minimizing invalid noise input, while also having a good difference null depth, which can guarantee angle measurement accuracy and tracking performance, and has practical engineering application value.

[0096] A computer-readable storage medium stores a computer program thereon. When executed by a processor, the computer program causes the device containing the computer-readable storage medium to perform the sum-difference beamforming method based on a conformal array antenna as described above. The computer program includes computer program code, which may be in the form of source code, object code, executable file, or some intermediate form. The computer-readable medium may include any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), random access memory, and other memories.

[0097] An electronic device includes a memory and a processor, wherein the memory stores a program executable on the processor, and the processor executes the program to implement the sum and difference beamforming method based on a conformal array antenna as described above.

[0098] If the modules / units integrated in the electronic device described in this application are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of this application can also be implemented by a computer program instructing related hardware devices. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above.

[0099] Furthermore, the computer-readable storage medium may primarily include a stored program area and a stored data area, wherein the stored program area may store the operating system, an application program required for at least one function, etc.; and the stored data area may store data created based on the use of blockchain nodes, etc.

[0100] The computer-readable storage medium stores computer-readable instructions, which are executed by a processor in an electronic device to implement the sum and difference beamforming method based on conformal array antennas as described in any of the above embodiments.

[0101] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and other division methods may be used in actual implementation.

[0102] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

[0104] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0105] Note that the above description is merely a preferred embodiment and application of the technical principles of the present invention. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the specific embodiments described herein, and may include many other effective embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A sum-difference beamforming method based on a conformal array antenna, wherein the conformal array antenna is composed of a cylindrical array and a spherical array disposed on the cylindrical array, and multiple layers of antenna elements are disposed on the conformal array antenna, with each layer of antenna elements uniformly disposed on the corresponding cylindrical or spherical array; characterized in that: Includes the following steps: A: Establishment of coordinate systems: Establish the frontal coordinate system OXYZ and the auxiliary coordinate system OX0Y0Z0, where the direction of incoming waves is parallel to the X0 axis of the auxiliary coordinate system; B: Coordinate transformation, converting the coordinates of the antenna element in the array coordinate system to the coordinates in the auxiliary coordinate system; C: Calculate the angle between the incoming wave and the normal to the antenna element; D: Compare the angle between the obtained incoming wave and the antenna element normal with the set maximum incident angle. If the angle between the incoming wave and the antenna element normal is less than or equal to the maximum incident angle, the antenna element is determined to be a working antenna element; otherwise, it is determined to be an invalid antenna element. E: Coordinate translation, the amount of translation along the Y0 coordinate axis calculated based on the sum of the antenna gains of all effectively operating antenna elements in the conformal array. y0 and the translation Trans on the Z0 coordinate axis z0 After obtaining the new coordinate plane OY1Z1, the new coordinates of the effectively working antenna element projected onto the coordinate plane OY1Z1 can be obtained, denoted as (y i1 ,z i1 ); F: By appropriately optimizing the planar array half-array method, the sum and difference beams of the conformal array are finally extracted.

2. The sum and difference beam division method based on conformal array antennas according to claim 1, characterized in that: In step A, the azimuth angle of the incoming wave is denoted as... If the pitch angle is θ, then the auxiliary coordinate system OX0Y0Z0 rotates counterclockwise by θ around the Y0 axis and then clockwise around the Z0 axis. Afterwards, it coincides with the array coordinate system OXYZ. According to the rotation relationship, the auxiliary coordinate system Y0 axis is coplanar with OXY, and the array coordinate system Z axis is coplanar with OX0Z0.

3. The sum and difference beam division method based on conformal array antennas according to claim 1, characterized in that: Step B specifically includes the following steps: The transformation matrix from the auxiliary coordinate system OX0Y0Z0 to the frontal coordinate system OXYZ is: The array coordinate system OXYZ rotates counterclockwise around the Z-axis. Then, after rotating clockwise by θ around the Y-axis, it coincides with the auxiliary coordinate system OX0Y0Z0. The transformation matrix from the frontal coordinate system OXYZ to the auxiliary coordinate system OX0Y0Z0 is: Let the coordinates of antenna element i in the array coordinate system OXYZ be... The coordinates transformed to the auxiliary coordinate system OX0Y0Z0 are:

4. The sum and difference beam division method based on conformal array antennas according to claim 1, characterized in that: Step C specifically includes the following steps: Given the azimuth angle of the incoming wave as... The elevation angle is θ, and in the coordinate system OXYZ, the direction of the incoming wave is equivalent to a vector (x, y, z), where... z = sinθ; the normal vector of antenna element i is (x′ i ,y′ i ,z′ i If the direction of the incoming wave is Δ, then the angle Δ between the direction of the incoming wave and the normal of antenna element i is... i for:

5. The sum and difference beam division method based on conformal array antennas according to claim 1, characterized in that: Step E specifically includes the following steps: E1: Project the effectively working antenna element i onto the OY0Z0 plane, that is, its coordinates on the OY0Z0 plane are (y io ,z i0 ); E2: Based on the angle Δ between the normal of antenna element i and the incoming wave. i Find the antenna gain G by looking up the table. i ; E3: Sum the antenna gains of all effectively working antenna elements to obtain the summed gain G. sum ; E4: Set the coordinate values ​​of each antenna y io With antenna gain G i Multiply and then sum to get the sum Sum y*g ; E5: Set the coordinate values ​​of each antenna z io With antenna gain G i Multiply and then sum to get the sum Sum z*g ; E6: Sum y*g Divide by G sum The translation amount Trans on the Y0 coordinate axis is obtained. y0 ; E7: Sum z*g Divide by G sum The translation amount Trans on the Z0 coordinate axis is obtained. z0 ; E8: Translate the coordinate plane OY0Z0 along the Y0 coordinate axis. y0 Then translate along the Z0 coordinate axis Trans z0 The new coordinate plane OY1Z1 is obtained, and the coordinates of antenna element i projected onto coordinate plane OY1Z1 are (y i1 ,z i1 ),in: y i1 = y i0 -Trans y0 Equation (5) z i1 = z i0 -Trans z0 Equation (6) 6. The sum and difference beam division method based on conformal array antennas according to claim 1, characterized in that: Step F specifically includes the following steps: F1: Beam determination: All units determined to be working are set to beam; F2: Azimuth difference beam determination: setting the threshold thr y This threshold is a small positive number, which can be determined based on specific antenna deployment and simulation results; for the effective working unit projected onto the coordinate plane OY1Z1, when y i1 >thr y When y is positive, the antenna element is determined to have an azimuth difference of +; when y is negative, the antenna element i1 <-thr y At that time, the antenna element is determined to have an azimuth difference of -. F3: Determining the pitch difference beam: Setting the threshold thr z This threshold is a small positive number, which can be determined based on specific antenna deployment and simulation results; for effective working units projected onto the coordinate plane OY1Z1, when z i1 >thr z When z is positive, the unit is determined to be pitch difference +; when z is negative, the pitch difference is +. i1 <-thr z At that time, the unit was determined to be pitch difference -.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it causes the device containing the computer-readable storage medium to perform the sum and difference beam division method based on a conformal array antenna as described in any one of claims 1-7.

8. An electronic device, characterized in that, include: A memory and a processor, wherein the memory stores a program that can run on the processor, and the processor executes the program to implement the sum and difference beam division method based on a conformal array antenna as described in any one of claims 1-7.

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