A Method and System for Rapid Optimization of Sidelobes of a Planar Array Antenna in the Whole Space

Abstract

The present invention provides a method and system for rapidly optimizing the side lobes of the full-space beam of a planar array antenna, and relates to the technical field of radar antennas. The present invention collects and analyzes deformation data of key parts in real time, utilizes finite element analysis combined with electromagnetic field theory, so as to rapidly calculate and adjust array excitation, thereby minimizing the side lobes, and has significant advantages in real time and accuracy. It not only improves the overall performance of the system, but also provides theoretical and methodological support for more efficient antenna control and design, and is expected to bring about broad application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of radar antennas, and in particular to a method and system for quickly optimizing full-space beam side lobes of a planar array antenna. Background Art

[0002] In order to solve the impact of environmental changes (such as temperature, humidity, etc.) or deformation during use on the sidelobe optimization of antenna arrays in engineering applications, a new scheme for optimizing antenna sidelobes based on dynamic response parameters of mechanical deformation is proposed. This scheme focuses on accurately monitoring the tiny mechanical deformation of the array structure, and adjusts the array excitation in real time by associating it with the sidelobe changes to maintain beam stability and improve the radar's anti-interference capability; however, traditional methods mostly rely on the optimization of static models or preset scenarios, and often cannot quickly respond to performance changes caused by structural deformation in the actual working environment. This leads to limitations in the response speed and accuracy of existing technologies in dynamic environments, especially in mobile communications and complex electromagnetic environments that require real-time adjustment.

[0003] In the prior art, the publication number is CN108959788A, and the name is a method for fast optimization of the side lobes of the full spatial beam of a planar array antenna. Aiming at the disadvantage of low efficiency of the planar array antenna in optimizing the side lobes of the full spatial beam, the antenna beam characteristics are used to quickly find the main lobe and side lobe areas of the full spatial beam of the antenna, thereby achieving the purpose of fast optimization of the side lobes of the full spatial beam of the antenna. This method can significantly improve the efficiency of side lobe optimization, and is simple to implement, has good versatility, and does not depend on the element type of the planar array antenna unit;

[0004] Although existing technologies provide some solutions for array antenna optimization, such as genetic algorithms and particle swarm optimization, which perform well in static scenarios, these methods often fail to meet real-time requirements due to large computational complexity and slow convergence speed for complex electromagnetic environments involving dynamic changes in stress-strain. In addition, the failure to fully consider the changes in electromagnetic characteristics caused by the deformation of the array antenna structure makes the existing technology lack accuracy in the optimization process of the full-space beam sidelobes; therefore, in the face of rapidly changing electromagnetic conditions and large structural deformation scenarios, the shortcomings of existing planar array antenna optimization technology are obvious.

[0005] The above information disclosed in the above Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0006] The object of the present invention is to provide a method and system for fast optimization of full spatial beam side lobes of a planar array antenna, so as to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for quickly optimizing the sidelobe of a full-space beam of a planar array antenna, the specific steps including:

[0009] Step S1: Determine the key parts in the structure of the planar array antenna, and under the current external load, collect the change data of the strain, bending angle and surface displacement of these key parts in real time during the monitoring period to generate a deformation data set describing the deformation degree of each key part;

[0010] Step S2: Obtain the deformation data sets of each key part, and combine the mechanical parameters of the elastic modulus and Poisson's ratio, and establish a stress-strain response model of the array structure by using the finite element analysis method;

[0011] Step S3: Introduce the electromagnetic wave propagation model of the array structure into the stress-strain response model, and use the electromagnetic field theory to analyze the influence of the deformation data sets of each key part on the beam sidelobe in real time, so as to deduce the non-linear coupling relationship between the array excitation value and the sidelobe, and finally establish an objective function for minimizing the sidelobe. Then, solve the objective function through an optimization algorithm to calculate a new array excitation value;

[0012] Step S4: Analyze in combination with the deformation data sets of each key part, calculate a fast correction index, which is used to adjust the new array excitation value to obtain an adjusted array excitation value, and perform a fast array excitation adjustment according to the adjusted array excitation value.

[0013] A system for quickly optimizing the sidelobe of a full-space beam of a planar array antenna, the system being used to execute the method for quickly optimizing the sidelobe of a full-space beam of a planar array antenna, including:

[0014] A data acquisition module: used to determine the key parts in the structure of the planar array antenna, and under the current external load, collect the change data of the strain, bending angle and surface displacement of these key parts in real time during the monitoring period to generate a deformation data set describing the deformation degree of each key part;

[0015] A stress-strain response model establishment module: used to obtain the deformation data sets of each key part, and combine the mechanical parameters of the elastic modulus and Poisson's ratio, and establish a stress-strain response model of the array structure by using the finite element analysis method;

[0016] New array excitation value generation module: It is used to introduce the electromagnetic wave propagation model of the array structure into the stress-strain response model, and use electromagnetic field theory to analyze the influence of the deformation data sets of each key part on the beam sidelobe in real time, so as to deduce the non-linear coupling relationship between the array excitation value and the sidelobe, and finally establish an objective function for minimizing the sidelobe. Then, through an optimization algorithm, the objective function is solved to calculate the new array excitation value;

[0017] Correction module: It is used to analyze by combining the deformation data sets of each key part, calculate a fast correction index, which is used to adjust the new array excitation value to obtain an adjusted array excitation value, and perform fast array excitation adjustment according to the adjusted array excitation value.

[0018] Compared with the prior art, the beneficial effects of the present invention are: by collecting and analyzing the deformation data of key parts in real time, using finite element analysis combined with electromagnetic field theory to quickly calculate and adjust the array excitation, so as to realize the minimization of the sidelobe, with significant real-time and accuracy advantages; not only improving the overall performance of the system, but also providing theoretical and method support for more efficient antenna control and design, and promising a wide range of application prospects. Brief Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the overall method flow of the present invention;

[0020] Figure 2 It is a block diagram of the system module of the present invention. Detailed Embodiments

[0021] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with specific embodiments.

[0022] It should be noted that unless otherwise defined, the technical terms or scientific terms used in the present invention should have the ordinary meaning understood by those with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar terms used in the present invention do not represent any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms such as "connected" or "linked" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0023] Embodiment 1:

[0024] Please refer to Figure 1 , the present invention provides a technical solution:

[0025] A method for rapidly optimizing the sidelobes of the full-space beam of a planar array antenna. Hereinafter, the planar array antenna structure will be simply referred to as the array structure. The specific steps include:

[0026] Step S1: Determine the key parts in the planar array antenna structure, and under the current external load, collect the change data of the strain, bending angle, and surface displacement of these key parts in real time during the monitoring period to generate a deformation data set describing the deformation degree of each key part;

[0027] Further explanation, define the key parts of the array structure, including: the reflector, the feed region, and the array joints; and denote the reflector, the feed region, and the array joints as , and ;

[0028] Among them, i ∈ {1, 2,..., N}, i represents the index of the i-th feed region in the array structure, and N is the total number of feed regions; and the number of feed regions is equal to the number of array elements in the array structure; the planar array antenna is a unified planar structure, so the reflector is set singly; therefore, the number of array elements is also represented by {1, 2,..., N};

[0029] j ∈ {1, 2,..., M}, j represents the index of the j-th array joint in the array structure, and M is the total number of array joints;

[0030] During the monitoring period when the external load is applied, through digital image correlation (DIC) of the full-field optical measurement method, the strain, bending angle, and surface displacement of the reflector are respectively denoted as , and ; and denote the deformation data set of the reflector as ; they respectively represent the change values before and after the external load is not applied;

[0031] During the monitoring period when the external load is applied, the strain, bending angle, and surface displacement of the i-th feed region are respectively denoted as , and ; and denote the deformation data set of the i-th feed region as ; they respectively represent the change values before and after the external load is not applied;

[0032] During the monitoring period when the external load is applied, the strain, bending angle, and surface displacement of the j-th array joint are respectively denoted as , and ; and denote the deformation data set of the j-th array contact point as ; they respectively represent the change values before and after the external load is applied;

[0033] The description of Digital Image Correlation (DIC) is as follows:

[0034] In Digital Image Correlation (DIC) software, the strain, bending angle, and surface displacement of the reflective surface can all be calculated by processing and analyzing the displacement information of the image; specifically:

[0035] Displacement field calculation: The DIC software directly calculates the corresponding displacement field by tracking the movement of the speckle pattern at different loading stages, which represents the displacement change of the surface during the deformation process.

[0036] Strain calculation: After the displacement field data is analyzed, the DIC software can calculate the in-plane strain distribution. This is achieved through mathematical differentiation, including principal strain and shear strain parameters.

[0037] Bending angle analysis: By further analyzing the measured displacement and strain data, the DIC software can deduce the bending angle. The steps to obtain the strain, bending angle, and surface displacement of the reflective surface are as follows:

[0038] Record the initial state image: Take a reference image when the antenna is in the unloaded state, ensuring that the image resolution and lighting conditions are appropriate;

[0039] Apply an external load and take pictures: Apply static or dynamic loads step by step according to the test requirements;

[0040] At each loading stage, keep the camera stable and take multiple speckle images to record the deformation process.

[0041] Data analysis and image processing: Import all the images into the DIC software;

[0042] Perform image preprocessing to ensure the image quality, including denoising and contrast adjustment.

[0043] Displacement field calculation: Use the software to automatically identify and track the movement of the speckles and calculate the displacement field at each stage.

[0044] Strain and bending analysis: Calculate the strain field from the displacement data and perform bending angle analysis based on physical and mathematical models. Specifically, use the dedicated tools of the DIC software for strain analysis, and reliable data supports subsequent analysis.

[0045] And install strain gauges, fiber optic sensors, and laser interferometers at key positions;

[0046] Strain gauge layout: Place it in the areas where the structural stress of the antenna changes most sensitively, such as the feed area and the array contact point parts.

[0047] Optical fiber sensor layout: It is arranged in a relatively long array section to globally monitor the bending and deformation trends of the array. The "relatively long array section" is determined by the experimenter based on theoretical knowledge and will not be elaborated here;

[0048] Laser interferometer positioning: The position on the planar array antenna structure for precisely monitoring the minute displacements and bending angles on the surface of the array, especially suitable for the refined quantification of the bending degree.

[0049] Step S2: Obtain the deformation data sets of each key part, and combine the mechanical parameters of the elastic modulus and Poisson's ratio, and use the finite element analysis method (FEA) to establish a stress-strain response model of the array structure;

[0050] Further explanation, using the finite element analysis method to establish a stress-strain response model of the array structure specifically includes:

[0051] 1) Data collection and preparation:

[0052] 1.1) Obtain the actual deformation data sets of each key part;

[0053] Obtain the deformation data set of the reflector ;

[0054] The deformation data set of the i-th feed region ;

[0055] The deformation data set of the j-th array joint ;

[0056] 1.2) Determine the elastic modulus and Poisson's ratio of the planar array antenna material;

[0057] Material sample preparation: Cut standard samples from the actual antenna material for mechanical property testing.

[0058] Elastic modulus (E) determination: Use a universal material testing machine (such as Instron) to conduct tensile tests on the samples and determine the elastic modulus according to ASTM standards.

[0059] Poisson's ratio ( ) determination: In the same experiment, calculate Poisson's ratio by measuring the deformations in the tensile direction and the transverse direction.

[0060] Data recording: Record the measured E and values and conduct multiple repeated experiments to ensure the accuracy and reliability of the parameters.

[0061] 2) Finite element model construction of the planar array antenna:

[0062] 2.1) Establish a geometric model of the planar array antenna;

[0063] CAD Model Import: Use CAD software (such as SolidWorks or AutoCAD) to draw the detailed geometric structure of the planar array antenna, ensuring it is exactly the same as the actual antenna structure.

[0064] Refine Key Parts: Particularly refine the key parts that require high-precision analysis, ensuring that the density of the finite element mesh in these areas is high enough to capture subtle deformations.

[0065] 2.2) Assignment of Material Properties;

[0066] Material Library Selection: In the FEA software (such as ANSYS or ABAQUS), select the material property library corresponding to the actual material.

[0067] Parameter Input: Input the elastic modulus (E) and Poisson's ratio ( ) measured in Step 1.2 into the FEA model to ensure the accuracy of the material properties.

[0068] 2.3) Mesh Generation;

[0069] Mesh Type Selection: For key parts with complex geometry and stress concentration, select high-quality quadrilateral or hexahedral meshes; for simple parts, use hexahedral or simplified meshes.

[0070] Mesh Density Setting: Increase the mesh density in strain-sensitive areas (such as connection points, bending areas) to ensure simulation accuracy; use a lower density in other areas to save computational resources.

[0071] Mesh Independence Check: Conduct a mesh independence analysis to ensure the rationality of the mesh generation, and that the results do not change significantly with an increase in mesh density.

[0072] 3) Boundary Conditions and External Load Settings:

[0073] 3.1) Definition of Boundary Conditions;

[0074] Fixed Boundary: According to the actual installation method of the planar array antenna, fix the support boundary of the model to prevent the overall movement of the model during the simulation.

[0075] Symmetry Boundary: If the planar array antenna has symmetry, apply the symmetry boundary condition to reduce the computational amount.

[0076] 3.2) Application of External Loads;

[0077] Apply equivalent external forces (such as wind load, mechanical vibration) to the corresponding key parts according to the actual working environment of the planar array antenna.

[0078] Dynamic Load: If the environmental load of the array structure is dynamically changing, define the corresponding time-varying load conditions.

[0079] 3.3) Loading step setting;

[0080] Static analysis: Set gradually increasing static loads and observe the stress and strain responses of key parts in the array structure under different loads;

[0081] Dynamic analysis: Set dynamic load conditions, conduct time-domain or frequency-domain analysis, and capture the responses of the structure under dynamic loads.

[0082] 4.1) Define the relationship formula of the stress-strain response model as:

[0083] ;

[0084] where E is the elastic modulus; is the stress; is the reference strain of each key part in the array structure without external loads applied; is the Poisson's ratio; is the strain change caused by the stress in each key part of the array structure under the current external load.

[0085] In the FEA software, use the user-defined material model to input the above stress-strain relationship to ensure that the model correctly applies this relationship during the simulation;

[0086] 4.2) Model parameter calibration;

[0087] Initial calibration: Based on the material parameters measured in step 1.2), initially calibrate the stress-strain model.

[0088] Experimental verification: Conduct finite element simulation and actual test simultaneously, compare the results of both, and adjust the model parameters to improve the consistency.

[0089] 5) High-frequency simulation analysis and verification:

[0090] 5.1) Finite element simulation run:

[0091] Simulation settings: After confirming that all boundary conditions, external loads, and material properties are correct, start the finite element simulation.

[0092] 5.2) Result extraction and verification:

[0093] Stress-strain distribution: Extract the stress and strain distribution data of each key part under different external load conditions.

[0094] Data comparison: Compare the simulation results with the actual deformation data set collected in step 1.1) to verify the accuracy of the model.

[0095] Error analysis: Calculate the error between the simulation results and the actual data, and adjust the model parameters (such as mesh density, material properties) to reduce the error.

[0096] 6) Dynamic relationship analysis and model optimization:

[0097] 6.1) Establishment of dynamic relationship:

[0098] Data correlation: Correlate the stress-strain distribution data obtained from finite element simulation with the antenna beam sidelobe characteristics, and determine the quantitative relationship between the array structure deformation and the sidelobe level.

[0099] Frequency response analysis: Analyze the influence of the array structure deformation on the sidelobe at different frequencies, and establish a dynamic response relationship model.

[0100] Step S3: Introduce the electromagnetic wave propagation model of the array structure into the stress-strain response model, and use electromagnetic field theory to analyze the influence of the deformation data sets of each key part on the beam sidelobe in real time, so as to deduce the non-linear coupling relationship between the array excitation value and the sidelobe. Finally, establish an objective function for sidelobe minimization, and then solve the objective function through an optimization algorithm to calculate a new array excitation value;

[0101] Further explanation, the minimized objective function, and calculating a new array excitation value specifically include:

[0102] The deformation of the key part will cause the offset of the array element, thus affecting the directivity and sidelobe amplitude of the beam;

[0103] An array element is each independent radiation unit that constitutes an antenna array;

[0104] 7.1) Select an electromagnetic simulation software (such as CST Microwave Studio or HFSS) to ensure the accuracy of electromagnetic field calculation.

[0105] Select software based on the finite element method (FEM) to enable seamless integration with the finite element analysis (FEA) stress-strain model.

[0106] 7.2) Import the finite element stress-strain response model:

[0107] Import the stress-strain response model established in step S2 into the electromagnetic simulation software; ensure the consistency of geometric structures and material parameters.

[0108] Ensure that the electromagnetic model contains the deformation data sets of all key parts to reflect the influence of stress-strain on the array structure;

[0109] 7.3) Define the electromagnetic characteristics of the array element:

[0110] Specify the electromagnetic parameters (such as dielectric constant, conductivity) within the frequency range for each array element to ensure matching with the actual working environment.

[0111] Define the array excitation values of the array elements including amplitude and phase; and determine that the array structure contains array elements, , and the array excitation value of each array element is determined by the amplitude and the phase ; denote the array excitation value as , and represent it using a vector as follows:

[0112] ;

[0113] where and represent the amplitude and phase of the th array element respectively;

[0114] Set the initial array excitation value of each array element to , and define it as the initial input variable of the optimization algorithm; this initial array excitation value will be updated as the "current excitation value" during the optimization process;

[0115] 8) Sidelobe impact analysis:

[0116] 8.1) Simulate the electromagnetic wave propagation under different stress-strain states:

[0117] In the simulation software, apply different stress-strain states under different array excitation value configurations, run the electromagnetic wave propagation simulation, and record the beam sidelobe data under each stress-strain state;

[0118] Each array element has its physical adjustment range, such as the maximum and minimum power outputs, voltage phase change range, and thus different array excitation value configurations are obtained.

[0119] 8.2) Extract the beam sidelobe characteristics from the beam sidelobe data:

[0120] Define as the index of the sidelobe direction; use the post-processing function of the simulation software to extract the sidelobe amplitude in the th sidelobe direction;

[0121] Extract the sidelobe amplitudes under different stress-strain states and the corresponding array excitation values , and thereby establish the following non-linear function relationship between the sidelobe amplitude and the array excitation value:

[0122] ;

[0123] Among them, is the non - linear relationship function between the array excitation value and the sidelobe amplitude; is the error term, representing the deviation caused by modeling errors or random factors; It is determined by using Statistical Error Analysis or Parameter Identification and Regression Method;

[0124] Use the post - processing function of the simulation software to extract the sidelobe amplitude in the th sidelobe direction; The specific steps are as follows:

[0125] View the far - field results:

[0126] After the electromagnetic wave propagation simulation is completed, navigate to the "Results" tab.

[0127] In CST, select "Farfields"; in HFSS, select "Fields" > "Radiation Pattern". This operation visualizes the antenna radiation pattern.

[0128] Generate the radiation pattern:

[0129] Select the view plane:

[0130] Select a suitable plane (such as the E - plane or H - plane) to facilitate observing the characteristics of the radiation pattern.

[0131] Display the results:

[0132] Generate and view the radiation pattern to clarify the specific positions and amplitudes of the main lobe and sidelobes.

[0133] Identify the sidelobes:

[0134] Analyze the radiation pattern:

[0135] On the generated radiation pattern, the main lobe is shown as the direction of the highest amplitude, while the sidelobes are located on the sides or other directions of the main lobe.

[0136] Mark the sidelobes:

[0137] Use the annotation tool of the simulation software to identify and determine the sidelobe position in the th sidelobe direction.

[0138] Extract the sidelobe amplitude in a specific direction, as follows:

[0139] Export the far - field data:

[0140] In the "Radiation Pattern" graph, right-click on the graph area and select "Export" or "Data" > "Export Data".

[0141] Export the radiation pattern data as a CSV file for further analysis.

[0142] Process the data file:

[0143] Open the exported data file, locate and record the sidelobe amplitude at the .

[0144] Add the extracted sidelobe amplitude at the to the dataset or optimize the model.

[0145] Prepare for subsequent analysis:

[0146] Ensure that the saved data is convenient for subsequent objective function calculation and minimization optimization process.

[0147] Systematically record all sidelobe directions to form a complete sidelobe amplitude dataset.

[0148] 8.3) Construct the objective function for sidelobe minimization, specifically:

[0149] Set the target sidelobe amplitude as , and establish the objective function for sidelobe minimization:

[0150] ;

[0151] where represents the total number of sidelobe directions affected by the array structure deformation data;

[0152] is the objective function for sidelobe minimization, represents the sidelobe amplitude at the th sidelobe direction due to the array structure deformation; is used to describe the degree of difference between the sidelobe amplitude at the th sidelobe direction caused by the array structure deformation and the target sidelobe amplitude ;

[0153] The sidelobe amplitude is the amplitude of the secondary radiation direction relative to the maximum radiation direction of the main lobe in the antenna radiation pattern. The radiation pattern of the antenna shows a main radiation peak (i.e., the main lobe) and several smaller secondary peaks, which are the sidelobes; the sidelobe amplitude refers to the radiation intensity of these secondary peaks;

[0154] 8.4) Establishment of Nonlinear Coupling Relationship and Construction of Optimization Model:

[0155] 8.41) Analyze the Nonlinear Relationship between Stress and Sidelobe:

[0156] Based on simulation data, plot the relationship curve between stress-strain and sidelobe amplitude to identify the nonlinear coupling characteristics;

[0157] Use regression analysis or machine learning methods to fit the nonlinear relationship between stress-strain and sidelobe amplitude; ensure the high precision of the model;

[0158] Set the sidelobe amplitude to be affected by stress and strain, and define the expression of the nonlinear relationship between stress-strain and sidelobe amplitude as:

[0159] ;

[0160] is a nonlinear function describing the influence of stress and strain on sidelobe amplitude; it is used to convert the input stress and strain information into sidelobe amplitude;

[0161] is the error term, which is used to represent random error or modeling deviation; Determine it by using Statistical Error Analysis or Parameter Identification and Regression Method;

[0162] The form of is fitted and modeled in the following way:

[0163] Polynomial regression model or exponential function regression model or neural network model.

[0164] 8.42) Construct a Nonlinear Optimization Model:

[0165] Based on the fitted nonlinear relationship, construct the nonlinear coupling relationship between the array excitation value and the sidelobe, and characterize this nonlinear coupling relationship with the following nonlinear optimization model:

[0166] ;

[0167] Among them, represents the current stress and strain under the condition, which is the sidelobe objective function value of the constructed nonlinear optimization model;

[0168] is a kind of nonlinear coupling relationship, which is used to optimize the overall objective function;

[0169] Through the fitted non - linear coupling relationship , clarify the non - linear correlation between the array excitation values (including amplitude and phase) and the sidelobe variation, and finally realize the sidelobe suppression optimization based on the excitation value adjustment by optimizing the objective function;

[0170] Ensure that the optimization model can capture the complex influence of stress - strain on the sidelobe amplitude.

[0171] 9) Selection and application of optimization algorithms

[0172] 9.1) Select a suitable non - linear optimization algorithm:

[0173] For the constructed non - linear optimization model, use the Particle Swarm Optimization (PSO) algorithm to obtain new array excitation values; the high efficiency and global search ability of particle swarm optimization in dealing with high - dimensional non - linear problems. The specific steps are as follows:

[0174] Set the population size, iteration number and convergence criterion of PSO to balance the optimization speed and accuracy.

[0175] 9.2) Implement the optimization process:

[0176] Initialize the particle swarm, and define the optimization variables as the amplitude and phase of the array excitation value;

[0177] In each iteration, run the electromagnetic simulation through the current array excitation value, and calculate the optimization objective value based on the sidelobe minimization objective function and update the velocity and position of the particles accordingly, gradually approaching the minimum value of the non - linear optimization model of the minimum value.

[0178] It should be clear that: is the basis of the non - linear optimization model of the basis.

[0179] Continue to iterate until the preset optimization accuracy or the maximum number of iterations is reached.

[0180] 10) Calculate the new array excitation values:

[0181] 10.1) Extract the optimization results:

[0182] Determine the global optimal solution, and obtain the new array excitation values corresponding to the minimized objective function. The new array excitation values include: amplitude and phase;

[0183] 10.2) Apply the new array excitation values:

[0184] Feed the new array excitation value back to the actual control system of the planar array antenna to achieve real-time suppression and optimization of the beam sidelobe.

[0185] 10.3) Verify the optimization effect:

[0186] Run the new excitation configuration and confirm that the sidelobe amplitude has reached the target level through actual measurement or further simulation.

[0187] If the requirements are not met, return to step 5) for further optimization, adjusting the algorithm parameters or optimizing the process.

[0188] Step S4: Analyze by combining the deformation data sets of each key part, calculate the fast correction index, which is used to adjust the new array excitation value to obtain the adjusted array excitation value, and perform fast array excitation adjustment according to the adjusted array excitation value;

[0189] Further explanation, for the fast correction index, specifically includes:

[0190] Apply the Min-Max normalization function to , and respectively, and the output values are all limited within the range of (0,1);

[0191] Denote the normalized output values of as , and respectively;

[0192] Denote the normalized output values of as , and respectively;

[0193] Denote the normalized output values of as , and respectively;

[0194] , and represent the upper deformation threshold of , and respectively; and , and all take values within the interval (0,1);

[0195] , and represent , and the upper limit of the deformation threshold; and , and are all within the range of (0, 1);

[0196] , and respectively represent , and the upper limit of the deformation threshold; and , and are all within the range of (0, 1);

[0197] Define the first deformation coefficient used to describe the degree of deformation of the reflector surface as , and the calculation formula is:

[0198] ;

[0199] , and are determined through the maintenance technical manual of the planar array antenna or relevant reference documents or expert experience knowledge, and will not be elaborated;

[0200] If or or the ratio of is greater than 1, it indicates that the degree of deformation of the reflector surface has an impact on the new array excitation value;

[0201] If or or the ratios of are all equal to 1, it indicates that the impact of the degree of deformation of the reflector surface on the new array excitation value can be ignored, but it is necessary to improve the continuous monitoring of the deformation of the reflector surface to avoid its severe deformation;

[0202] If or or the ratios of are all less than 1, it indicates that the degree of deformation of the reflector surface has no impact on the new array excitation value;

[0203] Define the second deformation coefficient used to describe the degree of deformation of the feed region as , and the calculation formula is:

[0204] ;

[0205] , and It is determined through the maintenance technical manual of the planar array antenna, or relevant reference documents, or expert experience and knowledge, which will not be elaborated here;

[0206] If or or When the ratio of is greater than 1, it indicates that the deformation degree occurring in the feed region has an impact on the new array excitation value;

[0207] If or or When the ratios of are all equal to 1, it indicates that the impact of the deformation degree occurring in the feed region on the new array excitation value can be ignored, but it is necessary to enhance the continuous monitoring of the deformation of the reflector to avoid its severe deformation degree;

[0208] If or or When the ratios of are all less than 1, it indicates that the deformation degree occurring in the feed region has no impact on the new array excitation value;

[0209] Define the third deformation coefficient used to describe the deformation degree of the array joints as , and the calculation formula is:

[0210] ;

[0211] , and It is determined through the maintenance technical manual of the planar array antenna, or relevant reference documents, or expert experience and knowledge, which will not be elaborated here;

[0212] If or or When the ratio of is greater than 1, it indicates that the deformation degree occurring in the array joints has an impact on the new array excitation value;

[0213] If or or When the ratios of are all equal to 1, it indicates that the impact of the deformation degree occurring in the array joints on the new array excitation value can be ignored, but it is necessary to enhance the continuous monitoring of the deformation of the reflector to avoid its severe deformation degree;

[0214] If or or When the ratios of are all less than 1, it indicates that the deformation degree occurring in the array joints has no impact on the new array excitation value;

[0215] Comprehensively analyze by combining the first deformation coefficient, the second deformation coefficient, and the third deformation coefficient, and define the fast correction index as , and the calculation formula is as follows:

[0216] ;

[0217] where d1, d2, and d3 are the weight coefficients of the corresponding coefficients respectively, and d1 + d2 + d3 = 1. The value ranges of d1, d2, and d3 are all within the interval (0, 1); the corresponding weights of d1, d2, and d3 are determined by the entropy weight method and the fuzzy analytic hierarchy process (FAHP), which will not be elaborated here;

[0218] Denote the amplitude and phase included in the new array excitation value as and ;

[0219] Define the amplitude and phase corresponding to the adjusted array excitation value as and respectively; and the corresponding calculation formulas are as follows:

[0220] ;

[0221] ;

[0222] Fast array excitation adjustment includes: according to the calculated and , correct the amplitude and phase of each element of the array structure, and apply the correction value to the amplitude and phase of the array excitation value in real time to feedback and update the array excitation in real time, and ensure that the sidelobe amplitude is within the preset threshold; the preset threshold is determined based on the anti-interference requirements;

[0223] After feedback-adjusting the array excitation value, monitor the deformation of the array structure in real time through a closed-loop control mechanism to ensure that the sidelobe amplitude always meets the anti-interference requirements of the current radar system.

[0224] The above formulas are all dimensionless and take their numerical calculations. The formula is obtained by collecting a large amount of data for software simulation to get a formula closest to the real situation. The preset parameters in the formula are set by those skilled in the art according to the actual situation.

[0225] Embodiment 2:

[0226] Please refer to Figure 2 , a fast optimization system for the full-space beam sidelobe of a planar array antenna. The system is used to execute the fast optimization method for the full-space beam sidelobe of the planar array antenna, including:

[0227] Data acquisition module: It is used to determine the key parts in the planar array antenna structure, and under the current external load, in the monitoring time period, it collects the change data of strain, bending angle and surface displacement of these key parts in real time to generate a deformation data set describing the deformation degree of each key part;

[0228] Stress-strain response model establishment module: It is used to obtain the deformation data set of each key part, and combined with the mechanical parameters of elastic modulus and Poisson's ratio, it uses the finite element analysis method to establish the stress-strain response model of the array structure;

[0229] New array excitation value generation module: It is used to introduce the electromagnetic wave propagation model of the array structure into the stress-strain response model, and use the electromagnetic field theory to analyze the influence of the deformation data set of each key part on the beam sidelobe in real time, so as to deduce the non-linear coupling relationship between the array excitation value and the sidelobe, and finally establish an objective function for minimizing the sidelobe. Then, through an optimization algorithm, the objective function is solved to calculate a new array excitation value;

[0230] Correction module: It is used to analyze in combination with the deformation data set of each key part, calculate a fast correction index, which is used to adjust the new array excitation value to obtain an adjusted array excitation value, and perform a fast array excitation adjustment according to the adjusted array excitation value.

[0231] The above embodiments can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed in this article can be implemented by electronic hardware, or by the combination of computer software and electronic hardware. Whether these functions are executed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0232] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units. They may be located in one place, or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0233] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and all should be covered by the protection scope of this application.

Claims

1. A method for fast optimization of full spatial beam side lobes of a planar array antenna, hereinafter referred to as an array structure, characterized in that: The specific steps include: Step S1: determining the key parts in the planar array antenna structure, and collecting the strain, bending angle and surface displacement change data of these key parts in real time during the monitoring period under the current external load, so as to generate a deformation data set describing the deformation degree of each key part; Step S2: Obtain the deformation data set of each key part, and use the finite element analysis method to establish the stress-strain response model of the array structure in combination with the mechanical parameters of elastic modulus and Poisson's ratio; Step S3: Introduce the electromagnetic wave propagation model of the array structure into the stress-strain response model, and use the electromagnetic field theory to analyze in real time the influence of the deformation data set of each key part on the beam side lobe, so as to derive the nonlinear coupling relationship between the array excitation value and the side lobe, and finally establish the objective function of minimizing the side lobe, and then solve the objective function through the optimization algorithm to calculate the new array excitation value; Step S4: analyzing the deformation data sets of each key part and calculating the rapid correction index, which is used to adjust the new array excitation value to obtain the adjusted array excitation value, and performing rapid array excitation adjustment according to the adjusted array excitation value; Define the key parts of the array structure, including: reflection surface, feed area and array connection point; and record the reflection surface, feed area and array connection point as , and ; Wherein, i∈{1,2,…,N}, i represents the index of the i-th feed region in the array structure, and N is the total number of feed regions; and the number of feed regions is equal to the number of array elements in the array structure; j∈{1,2,…,M}, j represents the index of the jth array node in the array structure, and M is the total number of array nodes; During the monitoring period when the external load is applied, the strain, bending angle and surface displacement of the reflective surface are recorded as , and ; and the deformation data set of the reflection surface is recorded as ; During the monitoring period of external load application, the strain, bending angle and surface displacement of the i-th feed region are recorded as , and ; and the deformation data set of the i-th feed area is recorded as ; During the monitoring period of external load application, the strain, bending angle and surface displacement of the jth array joint are recorded as , and ; and the deformation data set of the jth array joint is recorded as ; The finite element analysis method is used to establish the stress-strain response model of the array structure, including: 1) Data collection and preparation: 1.1) Obtain the actual deformation data set of each key part; 1.2) Determine the elastic modulus and Poisson’s ratio of planar array antenna materials; 2) Construction of finite element model of planar array antenna; 3) Boundary conditions and external load settings; 4) The relationship formula defining the stress-strain response model is: Where E is the elastic modulus; for stress; It is the reference strain of each key part in the array structure without external load; is Poisson’s ratio; It is the stress of each key part in the array structure under the current external load. The strain changes caused by Minimize the objective function and calculate the new array excitation value, including: 7.1) Use electromagnetic simulation software CSTMicrowaveStudio to perform electromagnetic field calculations; 7.2) Import the finite element stress-strain response model: Importing the stress-strain response model established in step S2 into the electromagnetic simulation software; 7.3) Define the electromagnetic characteristics of the array element: Define the array excitation value of the array element including amplitude and phase; and determine the array structure including Array element, , the array excitation value of each array element is determined by the amplitude and Phase Determine; record the array excitation value as , The vector representation is as follows: in, and Respectively represent The amplitude and phase of each array element; Set the initial array excitation value of each array element to , defined as the initial input variable of the optimization algorithm; 8) Sidelobe impact analysis: 8.1) Simulating electromagnetic wave propagation under different stress-strain states: In the simulation software, different stress-strain states are applied under different array excitation value configurations, and electromagnetic wave propagation simulation is run to record the beam sidelobe data under each stress-strain state; 8.2) Extract beam sidelobe characteristics from beam sidelobe data: definition is the index of the sidelobe direction; use the post-processing function of the simulation software to extract the The sidelobe amplitude in the sidelobe direction ; Extracting sidelobe amplitudes under different stress-strain states and the corresponding array excitation value , in order to establish the following nonlinear functional relationship between the sidelobe amplitude and the array excitation value: in, It is a nonlinear relationship function between the array excitation value and the sidelobe amplitude; is the error term, which represents the deviation due to modeling error or random factors; 8.3) Construct the objective function for minimizing the side lobes, specifically: Set the target sidelobe amplitude to , establish the objective function of minimizing the side lobes: in, Indicates the total number of sidelobe directions involved due to the influence of array structure deformation data; The objective function for sidelobe minimization is, The first The sidelobe amplitude in each sidelobe direction; Used to describe the deformation of the array structure. The sidelobe amplitude in the sidelobe direction and the target sidelobe amplitude the degree of difference between 8.41) Analyze the nonlinear relationship between stress and side lobes: Identify nonlinear coupling characteristics through simulation data; Regression analysis was used to fit the nonlinear relationship between stress-strain and sidelobe amplitude; The sidelobe amplitude is set to be affected by stress and strain, and the nonlinear relationship between stress-strain and sidelobe amplitude is defined as: It is a nonlinear function that describes the effect of stress and strain on the sidelobe amplitude; it is used to convert the input stress and strain information into the sidelobe amplitude; is the error term, which is used to represent random error or modeling bias; 8.42) Constructing a nonlinear optimization model: By fitting the nonlinear relationship, the nonlinear coupling relationship between the array excitation value and the side lobe is constructed, and the nonlinear coupling relationship is characterized by the following nonlinear optimization model: in, Indicates the current stress and strain The sidelobe objective function value of the nonlinear optimization model constructed under the condition; It is a nonlinear coupling relationship used to optimize the overall objective function; By fitting the nonlinear coupling relationship , clarify the nonlinear relationship between array excitation value and sidelobe change, and finally realize the sidelobe suppression optimization based on excitation value adjustment by optimizing the objective function; 9.1) According to the constructed nonlinear optimization model, a particle swarm optimization algorithm is used to obtain a new array excitation value; the new array excitation value includes: amplitude and phase; among them, for the particle swarm optimization algorithm: The optimization variables are defined as the amplitude and phase of the array excitation value; In each iteration, an electromagnetic simulation is run based on the current array excitation values ​​to calculate the sidelobe minimization objective function ; Update the velocity and position of the particle, gradually approaching the minimum value of the sidelobe minimization objective function; Continue iterating until the preset optimization accuracy or maximum number of iterations is reached; 10.1) Extract optimization results: Determine the global optimal solution and obtain the new array excitation value corresponding to the minimized objective function. The new array excitation value includes: amplitude and phase; 10.2) Apply new array excitation values: The new array excitation value is fed back to the actual control system of the planar array antenna to achieve real-time suppression optimization of the beam sidelobe.

2. The method for fast optimization of full spatial beam side lobes of a planar array antenna according to claim 1, characterized in that: For the rapid correction index, it includes: The first deformation coefficient used to describe the deformation degree of the reflective surface is defined as , the calculation formula is: The second deformation coefficient used to describe the deformation degree of the feed area is defined as , the calculation formula is: The third deformation coefficient used to describe the deformation degree of the array joint is defined as , the calculation formula is: Among them, respectively , and The Min-Max normalization function is applied, and the output values ​​are limited to the range of (0,1); Will The standardized output values ​​are recorded as , and ; Will The standardized output values ​​are recorded as , and ; Will The standardized output values ​​are recorded as , and ; , and Respectively represent , and The upper deformation threshold of , and The value range is in the interval (0,1); , and Respectively represent , and The upper deformation threshold of , and The value range is in the interval (0,1); , and Respectively represent , and The upper deformation threshold of , and The value range is in the interval (0,1).

3. The method for fast optimization of full spatial beam side lobes of a planar array antenna according to claim 2, characterized in that: Combining the first deformation coefficient, the second deformation coefficient and the third deformation coefficient for comprehensive analysis, the rapid correction index is defined as , the calculation formula is as follows: Where d1, d2 and d3 are weight coefficients of the corresponding coefficients, and d1+d2+d3=1, and the value ranges of d1, d2 and d3 are all in the interval (0,1); The amplitude and phase of the new array excitation value are recorded as and ; The amplitude and phase corresponding to the adjusted array excitation value are defined as and ; and the corresponding calculation formula is as follows: Fast array excitation adjustment, including: based on calculated and , and correct the amplitude and phase of each element of the array structure.

4. A planar array antenna full-space beam sidelobe rapid optimization system, characterized by: The system is used to execute the planar array antenna full space beam sidelobe fast optimization method according to any one of claims 1 to 3, comprising: Data acquisition module: used to determine the key parts in the planar array antenna structure, and collect the strain, bending angle and surface displacement change data of these key parts in real time during the monitoring period under the current external load, so as to generate a deformation data set describing the deformation degree of each key part; Stress-strain response model building module: used to obtain the deformation data set of each key part, and combine the mechanical parameters of elastic modulus and Poisson's ratio to establish the stress-strain response model of the array structure using the finite element analysis method; New array excitation value generation module: used to introduce the electromagnetic wave propagation model of the array structure into the stress-strain response model, and use electromagnetic field theory to analyze the impact of the deformation data set of each key part on the beam sidelobe in real time, so as to derive the nonlinear coupling relationship between the array excitation value and the sidelobe, and finally establish the objective function of minimizing the sidelobe. Then, the objective function is solved by the optimization algorithm to calculate the new array excitation value; Correction module: used to analyze the deformation data sets of each key part and calculate the fast correction index, which is used to adjust the new array excitation value to obtain the adjusted array excitation value, and perform fast array excitation adjustment based on the adjusted array excitation value.

Images