A method and system for phase array antenna deformation compensation

Abstract

This invention discloses a method and system for deformation compensation of a phased array antenna. The method includes: deploying a distributed strain sensing network to collect antenna structural strain data in real time; obtaining a real-time strain data vector through signal conditioning and digital processing; calculating a three-dimensional displacement field through a deformation field reconstruction algorithm and obtaining the real-time position deviation of each array element through an interpolation algorithm; establishing a total phase error model including geometric phase error, near-field correction term, and mutual coupling correction term, and calculating the total phase error vector; generating a target compensation phase vector based on this and superimposing it onto the original beamforming phase vector to generate a driving phase vector for phase compensation of the antenna array; and monitoring the radiation performance in real time for closed-loop iterative optimization to ensure the stability of the antenna beam pointing accuracy and radiation performance.

Description

Technical Field

[0001] This invention relates to the field of phased array antenna technology, and relates to, but is not limited to, a method and system for compensating for deformation of a phased array antenna. Background Technology

[0002] Phased array antennas, which control the feed phase of each radiating element in the array to change the beam pointing, are core components of modern radar, communication, and navigation systems, and their performance directly determines the overall system effectiveness. In practical applications, antenna panels undergo physical deformation due to factors such as temperature changes, mechanical loads, wind loads, and vibrations, leading to spatial positional shifts between array elements. This, in turn, causes phase error accumulation, resulting in performance degradation issues such as beam pointing deviation, increased sidelobe levels, and decreased gain. Existing antenna deformation compensation methods are mainly divided into two categories: one is passive compensation, which suppresses antenna array structural deformation by incorporating high-rigidity mechanical structures and matching thermal control systems; the other is active external monitoring compensation, which uses external optical measurement equipment such as laser trackers and photogrammetry to collect discrete point displacement data of the antenna and combines empirical mechanical models or simplified algorithms to complete deformation compensation.

[0003] The aforementioned passive compensation methods rely on high-rigidity mechanical structures and thermal control systems, resulting in high costs and complex structures, as well as lag in dynamic deformation response. Active external detection compensation methods employ bulky external optical measurement and monitoring equipment, which is cumbersome to install and debug, highly susceptible to external environmental interference, and cannot achieve all-weather real-time online monitoring of antenna array deformation. This makes them unsuitable for time-varying operating environments such as high-maneuverability flight of aircraft and dynamic changes in satellite orbits. Furthermore, existing technologies do not consider the array mutual coupling effect caused by changes in element spacing due to array deformation, and do not correct the element excitation signal under mutual coupling interference, further limiting the overall deformation compensation accuracy and resulting in ineffective guarantee of antenna beam radiation performance. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a phased array antenna deformation compensation method and system to solve the technical problems of low antenna deformation compensation efficiency caused by the lag in dynamic deformation response and the inability to perform all-weather real-time online monitoring of antenna array deformation in the prior art. By monitoring antenna structural deformation in real time and performing adaptive beam compensation, the compensation accuracy is improved, so as to maintain the pointing accuracy and radiation performance of the antenna in dynamic deformation environment.

[0005] The technical solution of this invention is implemented as follows: In a first aspect, embodiments of the present invention provide a method for compensating for deformation of a phased array antenna, comprising: Step S1: Acquire the strain data of the antenna structure collected by the strain sensing network in real time, and preprocess the strain data of the antenna structure to obtain a real-time strain data vector; the strain sensing network consists of multiple strain sensors deployed at the target deployment position of the antenna panel. Step S2: Based on the real-time strain data vector, calculate the three-dimensional displacement field of the antenna panel in real time using the deformation field reconstruction algorithm; Step S3: Based on the three-dimensional displacement field, calculate the real-time spatial position of each element in the antenna array carried by the antenna panel using an interpolation algorithm, and calculate the real-time position deviation of each element based on the real-time spatial position and the ideal static position. Step S4: Calculate the total phase error vector based on the real-time position deviation of each array element; Step S5: Calculate the target compensation phase vector using the objective function based on the total phase error vector; Step S6: Superimpose the target compensation phase vector onto the original beamforming phase vector to generate a driving phase vector, and perform phase compensation on the antenna array based on the driving phase vector; Step S7: After the phase compensation is completed, the current antenna radiation performance is obtained in real time and the antenna radiation performance deviation is calculated. If the antenna radiation performance deviation exceeds the preset threshold, the optimization parameters in the objective function are adjusted and steps S5 to S7 are repeated until the antenna radiation performance deviation does not exceed the preset threshold or the preset number of iterations is reached, and the antenna deformation compensation is completed.

[0006] Secondly, embodiments of the present invention also provide a phased array antenna deformation compensation system, the system comprising a distributed strain sensing network, a strain data calculation and processing module, a beamformer, and a performance monitoring and evaluation module, wherein: The distributed strain sensing network collects antenna structure strain data in real time and sends it to the strain data calculation and processing module. After receiving the strain data of the antenna structure, the strain data calculation and processing module performs preprocessing, and based on the real-time strain data vector obtained from the preprocessing, calculates the target compensation phase vector through the objective function and sends it to the beamformer. The beamformer receives the target compensation phase vector calculated by the strain data calculation and processing module, superimposes the target compensation phase vector onto the original beamforming phase vector to generate a driving phase vector, and performs phase compensation on the antenna array based on the driving phase vector. After the phase compensation is completed, the performance monitoring and evaluation module acquires the current antenna radiation performance in real time and calculates the antenna radiation performance deviation. If the antenna radiation performance deviation exceeds a preset threshold, the optimization parameters in the objective function are adjusted and sent to the strain data calculation and processing module to recalculate the target compensation phase vector, so as to control the beamformer to perform phase compensation on the antenna array until the antenna radiation performance deviation after phase compensation does not exceed the preset threshold or reaches the preset number of iterations, and then stops, thus completing the antenna deformation compensation.

[0007] The technical solution provided in this application firstly achieves real-time high-precision sensing of the three-dimensional displacement field of the antenna panel by integrating a distributed strain sensing network with a deformation field reconstruction algorithm, providing an accurate deformation data basis for phase error compensation. Then, a total phase error model including geometric phase error, near-field correction term, and mutual coupling correction term is established, which comprehensively considers various phase disturbance factors caused by deformation, significantly improving the compensation accuracy, especially under large deformation or near-field working conditions. Finally, through real-time performance monitoring and closed-loop adaptive optimization, deformation changes are dynamically tracked and compensation parameters are continuously optimized to ensure the stable maintenance of antenna beam pointing accuracy and radiation performance, greatly improving the robustness and engineering practicality of the system. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments 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, wherein: Figure 1 This is a flowchart illustrating a phased array antenna deformation compensation method provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of the deformation field reconstruction algorithm provided in an embodiment of the present invention; Figure 3 This is a system block diagram of a phased array antenna deformation compensation system provided in an embodiment of the present invention. Detailed Implementation

[0009] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all embodiments. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention. 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.

[0010] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0011] It should be noted that the terms "first, second, and third" used in the embodiments of the present invention are only used to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, and third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of the present invention described herein can be implemented in an order other than that illustrated or described herein.

[0012] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which these embodiments of the invention pertain. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0013] In a phased array antenna system, the antenna array consists of a large number of array elements arranged in a predetermined spatial position. Each element controls the phase of its transmitted or received signal through a phase shifter or digital beamforming chip to achieve electronic beam scanning. However, in actual working environments, the antenna panel may undergo structural deformation due to various factors such as temperature changes, wind load, gravitational deformation, and vibration, causing the actual spatial position of the array elements to deviate from its ideal position. This positional deviation introduces additional phase errors, causing beam pointing to deviate, sidelobe levels to increase, and main lobe gain to decrease, severely affecting the overall performance of the antenna. Although some methods in the prior art can compensate for deformation to a certain extent, they often suffer from problems such as response lag, incomplete modeling, or inability to achieve closed-loop adaptive optimization. This invention addresses these shortcomings by proposing a phased array antenna deformation compensation method.

[0014] Figure 1 This is a flowchart illustrating a phased array antenna deformation compensation method provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes at least the following steps: Step S1: Acquire antenna structure strain data collected by the strain sensing network in real time, and preprocess the antenna structure strain data to obtain a real-time strain data vector. In this embodiment, the strain sensing network consists of multiple strain sensors deployed at the target deployment location on the antenna panel.

[0015] Specifically, strain sensors are deployed at the target locations on the antenna panel using the calculated deployment density to form a strain sensing network. The strain sensors in this network collect real-time strain data generated by the phased array antenna structure under stress or temperature changes, serving as the antenna structure strain data. This strain data reflects the degree of deformation in local areas of the antenna panel and forms the basis for subsequent reconstruction of the entire antenna panel's three-dimensional displacement field.

[0016] The strain sensor in this embodiment uses an FGB sensor (Fiber Bragg Grating sensor), which has strong resistance to electromagnetic interference, supports multi-point series connection, is resistant to high and low temperatures and has strong corrosion resistance, and can maintain stability for a long time.

[0017] Furthermore, in this embodiment, the deployment density is calculated backward based on the required compensation accuracy. The backward calculation process includes: First, determine the maximum permissible phase error based on the compensation accuracy; the corresponding calculation formula is as follows:

[0018] In the formula, Indicates the maximum permissible phase error; This represents the desired pointing accuracy, which is the beam pointing accuracy required by the system design. This desired pointing accuracy represents the maximum allowable beam pointing deviation. The 3dB beamwidth of an antenna, which is the beam coverage angle range (unit: rad) corresponding to a 3dB decrease in the antenna's main lobe gain, is used to normalize pointing accuracy and is a fundamental performance parameter of the antenna.

[0019] Then, based on the extension of the Nyquist sampling theorem, at the smallest characteristic scale of the antenna panel structure (shortest chord length)... When installing sensors, the spacing should meet the following requirements:

[0020] In the formula, Indicates the spacing between adjacent sensors. The smallest characteristic scale (shortest chord length) representing the antenna panel structure. The coefficients are determined based on the Nyquist sampling theorem (which requires the sampling frequency to be at least twice the highest frequency of the signal) and in combination with engineering margins.

[0021] The deployment density is calculated to ensure sufficient sampling of the deformation mode at the highest spatial frequency of the structure, thereby guaranteeing the reconstruction accuracy of the antenna deformation field.

[0022] In one embodiment, the process of determining the target deployment location includes: First, the high-strain sensitive regions of the antenna panel are determined using the finite element analysis (FEA) method. Assuming there are M mesh elements after mesh generation, for the top N elements of interest... modes First mode, establish strain energy matrix:

[0023] In the formula, Indicates the first Modal strain energy index of each grid cell Indicates the modal order selected. express First mode, This represents the strain vector of the m-th mesh element in the i-th mode.

[0024] Then select The location of the largest unit is taken as the critical location (usually K=0.2M), and combined with spatial uniformity constraints, a greedy algorithm is used to determine the final target deployment location.

[0025] In one embodiment, to ensure the accuracy and reliability of the antenna structure strain data, a series of preprocessing steps are required after the antenna structure strain data is acquired, including: 1) Demodulate the antenna structure strain data and convert the demodulated analog signal into the original digital signal.

[0026] Specifically, after acquiring the antenna strain data, the wavelength shift of the optical signal reflected from the optical fiber is first calculated using a wavelength demodulator, and then converted into a digital signal using a high-precision analog-to-digital converter (ADC). This digital signal is the original digital signal. It is important to note that in this embodiment, all signal acquisition channels must be sampled synchronously to ensure the temporal consistency of the data from each channel.

[0027] 2) The original digital signal is filtered by a low-pass filter, and temperature compensation is performed on the filtered digital signal to obtain the compensation strain vector.

[0028] Furthermore, this embodiment employs a 5th-order Butterworth low-pass filter, with the following filter transfer function:

[0029] In the formula, Represents the filter transfer function. This indicates the cutoff angular frequency of the filter. Represents a complex frequency variable. This represents the 5th order Butterworth filter. An extreme point.

[0030] Furthermore, in this embodiment, temperature compensation is performed on the filtered digital signal using a compensation model to obtain the compensation strain vector. Wherein, The compensation model is as follows:

[0031] In the formula, Represents the compensation strain vector. This represents the filtered digital signal. Indicates the temperature sensitivity coefficient. This indicates the sensor's calibration temperature. This indicates the current temperature measured by the sensor in real time.

[0032] 3) Detect and remove outliers from the compensation strain values ​​in the compensation strain vector to obtain the effective strain vector.

[0033] Specifically, an improved 3-σ criterion combined with a median filter is used to remove outliers from the compensation strain vector. For each signal acquisition channel (one signal acquisition channel corresponds to one strain sensor), at time... Compensation strain value If the following conditions are met: If it is determined to be an outlier, the valid value from the previous moment or the interpolation value from an adjacent signal acquisition channel will be used instead. This represents the mean of the compensation strain vector within the sliding window. This represents the standard deviation within the sliding window.

[0034] The effective strain vector is obtained by outlier detection and removal from the compensation strain values ​​in the compensation strain vector. for:

[0035] In the formula, Indicates the first Each signal acquisition channel at time The effective strain value, , Indicates the total number of signal acquisition channels; This is the symbol for a matrix device.

[0036] 4) Associate each element in the effective strain vector with the spatial coordinates of the corresponding sensor to obtain the real-time strain data vector.

[0037] Among them, the spatial coordinates of the sensor for:

[0038] In the formula, Indicates the first The spatial coordinates of each sensor This is the matrix transpose symbol.

[0039] The real-time strain data vector is obtained by associating each element of the effective strain vector with the spatial coordinates of the corresponding sensor. for:

[0040] The above signal conditioning can amplify weak structural strain signals and suppress noise, filtering can remove high-frequency interference, and temperature compensation can eliminate the influence of temperature changes on strain measurement values.

[0041] Step S2: Based on the real-time strain data vector, the three-dimensional displacement field of the antenna panel is calculated in real time using the deformation field reconstruction algorithm.

[0042] The deformation field reconstruction algorithm in this embodiment includes, but is not limited to, the modal superposition method and the finite element inversion method. Based on the acquired real-time strain data vector, the three-dimensional displacement at any position on the entire antenna panel is calculated to form a three-dimensional displacement field. This three-dimensional displacement field accurately describes the deformation state of the antenna panel in space, including the displacement along the X, Y, and Z directions.

[0043] In one embodiment, such as Figure 2 As shown, after obtaining the real-time strain data vector, the three-dimensional displacement field of the antenna panel is calculated in real time using the deformation field reconstruction algorithm, specifically including the following steps: Step 1: Determine the current estimated deformation based on the real-time strain data vector, and determine the deformation threshold based on the antenna operating wavelength.

[0044] The current formula for calculating the predicted deformation is:

[0045] In the formula, Indicates the current estimated deformation. This represents the maximum strain value in the real-time strain data vector. This indicates the characteristic dimension of the antenna panel. If the phased array antenna is a planar array type, the characteristic dimension of the antenna panel is the panel length; if the phased array antenna is a conformal array type, the characteristic dimension of the antenna panel is the radius of curvature.

[0046] The formula for determining the deformation threshold is:

[0047] In the formula, Indicates the deformation threshold. This indicates the operating wavelength of the phased array antenna.

[0048] Step 2: When the current estimated deformation is less than the deformation threshold, the modal superposition method is selected as the deformation field reconstruction algorithm to calculate the three-dimensional displacement field of the antenna panel in real time.

[0049] In one embodiment, the modal superposition method is selected as the deformation field reconstruction algorithm to calculate the three-dimensional displacement field of the antenna panel in real time, specifically including the following steps: 1) Obtain the structural modal shape matrix calculated from the finite element analysis model. The strain-displacement relationship matrix is ​​composed of the partial derivatives of the finite element shape functions with respect to spatial coordinates. .

[0050] 2) Based on structural mode shape matrix Strain-displacement relationship matrix Constructing the modal strain matrix , .

[0051] 3) Applying the least squares method to the real-time strain data vector and modal strain matrix The data is processed to obtain the real-time modal coordinate vector q(t).

[0052]

[0053] 4) Based on real-time modal coordinate vector q(t) and structural modal shape matrix Real-time calculation of the three-dimensional displacement field of the antenna panel .

[0054]

[0055] Step 3: When the real-time estimated deformation is greater than or equal to the deformation threshold, the finite element inversion method is selected as the deformation field reconstruction algorithm to calculate the three-dimensional displacement field of the antenna panel in real time.

[0056] In one embodiment, the finite element inversion method is selected as the deformation field reconstruction algorithm to calculate the three-dimensional displacement field of the antenna panel in real time, specifically including the following steps: 1) Obtain the regularization matrix calculated from the finite element analysis model. And the strain-displacement relationship matrix composed of the partial derivatives of the finite element shape functions with respect to spatial coordinates. .

[0057] Specifically, the strain-displacement relationship matrix It consists of the partial derivatives of the finite element shape functions with respect to the spatial coordinates of each node in the finite element model. The spatial coordinates of each node in the finite element model are used to reflect the geometric position of the model structure in three-dimensional space.

[0058] 2) Select the optimal regularization coefficient from the candidate set of regularization coefficients using the L-curve method or Generalized Cross-Validation (GCV). And based on the optimal regularization coefficient Strain-displacement relationship matrix Regularization matrix and real-time strain data vector Construct the regularization coefficient matrix and the strain projection equivalent vector.

[0059] Specifically, the optimal regularization coefficient is first selected from the candidate set of regularization coefficients using the L-curve method or generalized cross-validation (GCV). Then based on the optimal regularization coefficient Construct the Tikhonov regularization matrix, and finally combine the Tikhonov regularization matrix with the strain-displacement relationship matrix. Regularization matrix and real-time strain data vector Construct the regularization coefficient matrix and the strain projection equivalent vector.

[0060] 3) Based on the regularization coefficient matrix, strain projection equivalent vector, and real-time strain data vector, the three-dimensional displacement field of the antenna panel is calculated in real time. .

[0061]

[0062] In the formula, Represents the regularization coefficient matrix. For Tikhonov regularization terms, This represents the equivalent vector of strain projection.

[0063] Furthermore, when high real-time performance is required and the deformation modes are complex, such as in high-speed mobile platforms or strong wind environments, this embodiment selects a deep neural network as the deformation field reconstruction algorithm to calculate the three-dimensional displacement field of the antenna panel in real time. This deep neural network method constructs strain-displacement sample pairs using a large amount of finite element simulation or experimental data. ,in, Indicates the first A strain-displacement sample pair Indicates the first Real-time strain data vector in a strain displacement sample pair , Indicates the first The three-dimensional displacement field at the corresponding time point of each strain displacement sample pair , This represents the total number of strain-displacement sample pairs. A residual neural network (ResNet) or a long short-term memory network (LSTM) is trained using these strain-displacement sample pairs to learn the nonlinear mapping relationship from strain space to displacement space. Once the model training is complete, the real-time strain data vector can be... Input into a trained deep neural network to obtain real-time three-dimensional displacement field To meet real-time requirements.

[0064] Step S3: Based on the three-dimensional displacement field, calculate the real-time spatial position of each element in the antenna array carried by the antenna panel using an interpolation algorithm, and calculate the real-time position deviation of each element based on the real-time spatial position and the ideal static position.

[0065] Specifically, since the array elements are discretely mounted on the antenna panel and the positions of the array elements usually do not coincide with the positions of the finite element mesh nodes, after obtaining the three-dimensional displacement field, the discrete node displacement field output in step S2 is first extended into a continuous displacement function at any position on the panel surface using the radial basis function interpolation algorithm; then, the ideal position of each array element is substituted into the continuous displacement function to obtain the displacement at each array element, and its ideal position is superimposed to obtain the real-time spatial position.

[0066] After determining the real-time spatial position of each array element, the real-time spatial position of each array element is compared with its ideal position under ideal, undeformed conditions. The difference between the two is the position deviation of each array element, which is the direct basis for subsequent calculation of phase error.

[0067] Step S4: Calculate the total phase error vector based on the real-time position deviation of each array element.

[0068] Specifically, after obtaining the position deviation of each array element, this embodiment calculates the phase error of each array element by calculating the real-time geometric phase error, real-time near-field correction, and real-time mutual coupling phase correction of each array element, thereby obtaining the total phase error vector of all array elements.

[0069] The real-time geometric phase error of the array elements refers to the fundamental phase difference caused by the projection of the element position deviation onto the beam pointing direction, and is the main component of the phase error. However, under large array or near-field operating conditions, the second-order effect of element position offset on the path becomes non-negligible. Therefore, this embodiment introduces a near-field correction term to accurately describe this effect. Furthermore, the mutual coupling effect between array elements changes with the element spacing. The element position offset caused by deformation changes the mutual impedance between elements, thus affecting the excitation phase of each element. This embodiment establishes a deformed mutual coupling matrix through the mutual coupling correction term and uses a pre-established lookup table indexed by the element spacing to quickly calculate the change in mutual impedance caused by the change in element spacing, thereby correcting its effect on the element excitation phase. Through the comprehensive calculation of these three correction terms, the accurate phase error of each element can be obtained.

[0070] In one embodiment, the total phase error vector is calculated based on the real-time position deviation of each array element, specifically including the following steps: Step 1: Calculate the real-time geometric phase error of each array element by performing a dot product operation on the real-time position deviation of each array element and the beam pointing unit vector.

[0071]

[0072] In the formula, Indicates the first Each element at any moment Real-time geometric phase error; This represents the unit vector pointing the beam, that is, the unit vector in the direction the beam points. Indicates the first Each element at any moment Positional deviation, This indicates the operating wavelength of the phased array antenna.

[0073] Step 2: Determine whether the antenna array is operating in the near field region based on the real-time position deviation and Rayleigh distance of each array element. If it is operating in the near field region, calculate the real-time near field correction based on the real-time position deviation of each array element.

[0074] Specifically, the Rayleigh distance is determined based on the aperture size of the antenna array and the operating wavelength. The system determines whether the antenna array is operating in the near-field region based on the Rayleigh distance and the near-field determination coefficient. If it is operating in the near-field region, the system calculates the real-time near-field correction based on the real-time position deviation of each array element. If it is operating in the far-field region, this step is ignored.

[0075] In the formula, Indicates Rayleigh distance, Indicates the aperture size of the antenna array. This indicates the operating wavelength of the phased array antenna.

[0076] The formula for calculating the real-time near-field correction is:

[0077] In the formula, Indicates the first Each element at any moment Real-time near-field correction amount This indicates the operating wavelength of the phased array antenna. Indicates the distance to the target. Indicates the first Each element at any moment Positional deviation, This represents the unit vector pointing the beam, that is, the unit vector in the direction the beam points. Indicates the first Each element at any moment Positional deviation.

[0078] Furthermore, the distance between the antenna and the target being detected or the communication object is taken as the target distance. If the target distance is much smaller than the Rayleigh distance, the antenna array is operating in the near-field region; if the target distance is much larger than the Rayleigh distance, the antenna array is operating in the far-field region.

[0079] This embodiment quantizes the target distance as being much smaller than the Rayleigh distance. The target distance, which is much larger than the Rayleigh distance, is quantized into... , This is the near-field determination coefficient, with a value ranging from 1 to 10. The specific value can be set according to the system's accuracy requirements.

[0080] Step 3: Based on the real-time position deviation and ideal position of each array element, calculate the real-time change in the spacing between array elements before and after deformation. Then, obtain the change in mutual impedance by querying the mutual coupling coefficient lookup table through the real-time change in the spacing between array elements. Calculate the real-time mutual coupling phase correction of each array element based on the change in mutual impedance.

[0081] The formula for calculating the real-time mutual coupling phase correction is:

[0082] In the formula, Indicates the first Each element at any moment Real-time mutual coupling phase correction amount. Indicates the argument. Indicates the first Individual elements and the first Each element at any moment The change in mutual impedance can be quickly obtained through a pre-established mutual coupling coefficient lookup table (indexed by the element spacing). Indicates the first Each element at any moment The excitation current.

[0083] Step 4: Real-time geometric phase error based on all array elements Real-time near-field correction and real-time mutual coupling phase correction The total phase error vector is obtained.

[0084]

[0085]

[0086] In the formula, Indicates time The total phase error vector, Indicates the first Each element at any moment The total phase error.

[0087] Step S5: Calculate the target compensation phase vector using the objective function based on the total phase error vector.

[0088] Specifically, after calculating the total phase error vector, this embodiment further calculates the compensation phase vector required by the antenna array, i.e., the target compensation phase vector. The purpose of calculating the target compensation phase vector is to cancel the phase error caused by deformation, so that the antenna beam can be restored to the expected pointing and shape.

[0089] Furthermore, this embodiment employs either the reference zero-elimination method or the minimum mean square error (MMSE) method to construct the objective function. A time smoothing constraint term is introduced during the construction of the objective function to prevent abrupt changes in the compensation phase vector over time, ensuring the stability of beam control. Simultaneously, the quantization accuracy constraint of the phase shifter must also be considered, ensuring that the calculated target compensation phase vector conforms to the quantization step size of the phase shifter, so that it can be accurately executed by the actual hardware.

[0090] In one embodiment, when the antenna array control system is in the first operating mode, the total phase error vector is processed according to the reference zero-elimination method to construct the first objective function and obtain the initial compensation phase vector.

[0091] The first working mode of this embodiment refers to the fast real-time compensation mode. This mode is more sensitive to time delay (i.e., compensation speed) than to compensation accuracy. When in this mode, the reference zero elimination method is used to process the total phase error vector. The computation is small and the speed is fast. The phase compensation can be completed in the shortest time, ensuring that the system can respond quickly to dynamic deformation.

[0092] In one embodiment, when the antenna array control system is in the second operating mode, the total phase error vector is processed according to the minimum mean square error method to construct a second objective function, and the second objective function is minimized under the phase shifter quantization accuracy to obtain the initial compensation phase vector.

[0093] The second operating mode in this embodiment refers to the high-precision compensation mode. This mode is more sensitive to compensation accuracy than to compensation speed. In this mode, the minimum mean square error method is used to accurately process the total phase error vector. Considering factors such as phase shifter quantization error and thermal noise, the residual phase error after compensation is minimized. This mode has a relatively low response speed but the highest compensation accuracy, ensuring that the system can obtain a highly accurate compensated phase vector.

[0094] In one embodiment, the original construct of the objective function is:

[0095] In the formula, The terms represent the objective function value; the first term is the phase error residual term, which is zero, meaning the compensated phase vector completely cancels out the total phase error. The smaller this term is, the higher the compensation accuracy. The second term is the time smoothing constraint term, which is zero, meaning the compensated phase vector is exactly the same as the previous time step. The smaller this term is, the smoother the phase change and the more stable the system. Indicates time The total phase error vector, This represents the initial compensation phase vector. Represents the historical compensation phase vector. This represents the time smoothing coefficient.

[0096] If the reference zero-elimination method is used, then The objective function degenerates into The initial compensation phase vector is .

[0097] If the minimum mean square error method is used, the original construction of the objective function is completely preserved. The quantization accuracy constraint of the phase shifter is: In the formula, Indicates the first The initial compensation phase of each array element, where B is the number of bits in the phase shifter. This indicates the minimum quantization step size of the phase shifter. .

[0098] The initial compensation phase of all array elements is used as the initial compensation phase vector. After obtaining the initial compensation phase vector, time smoothing constraint processing is performed on the initial compensation phase vector to obtain the smoothed compensation phase. Then, the smoothed compensation phase is constrained by the quantization step size determined by the number of phase shifter bits B (i.e., the compensation phase of each array element must be taken as...). (integer multiples thereof) to obtain the target compensation phase vector.

[0099] Step S6: Superimpose the target compensation phase vector onto the original beamforming phase vector to generate the driving phase vector, and perform phase compensation on the antenna array based on the driving phase vector.

[0100] Specifically, after obtaining the target compensation phase vector, it is superimposed on the original beamforming phase vector to generate a new driving phase (i.e., driving phase vector). The beamforming controller then controls the array element phase shifters or digital beamforming chips to perform phase compensation. In this way, even if the antenna panel deforms, the antenna beam can still maintain ideal pointing and performance by adjusting the driving phase of each array element in real time.

[0101] Step S7: After the phase compensation is completed, the current antenna radiation performance is obtained in real time and the antenna radiation performance deviation is calculated. If the antenna radiation performance deviation exceeds the preset threshold, the optimization parameters in the objective function are adjusted and steps S5 to S7 are repeated until the antenna radiation performance deviation does not exceed the preset threshold or the preset number of iterations is reached, and the antenna deformation compensation is completed.

[0102] Specifically, to ensure the continued effectiveness of antenna deformation compensation, this embodiment also introduces a closed-loop iterative optimization mechanism. The antenna radiation performance deviation is calculated by real-time monitoring of the antenna's radiation performance. When the deviation exceeds a preset threshold, the optimization parameters in the objective function are adjusted, and steps S5 to S7 are repeated, forming a real-time closed-loop phase compensation mechanism to always maintain the antenna in its optimal operating state.

[0103] This embodiment avoids the phase compensation mechanism from getting stuck in an infinite loop by setting a preset number of iterations. When the antenna radiation performance deviation has reached or exceeded a preset threshold within the preset number of iterations, it indicates that the antenna deformation compensation has been completed. When the antenna radiation performance deviation has reached the preset number of iterations but still exceeds the preset threshold, an alarm is triggered to notify the staff and the log is recorded.

[0104] In one embodiment, the current antenna radiation performance includes the current beam pointing angle, the current sidelobe level, and the current main lobe gain; calculating the antenna radiation performance deviation specifically includes the following steps: 1) Obtain the ideal beam pointing angle, and calculate the absolute value of the beam pointing error based on the current beam pointing angle and the ideal beam pointing angle.

[0105]

[0106] In the formula, This represents the absolute value of the beam pointing error. Indicates the current beam pointing angle. This indicates the ideal beam pointing angle.

[0107] 2) Obtain the sidelobe level design value, and calculate the sidelobe level deviation value based on the current sidelobe level value and the sidelobe level design value.

[0108]

[0109] In the formula, This indicates the sidelobe level deviation value. Indicates the current sidelobe level value. This indicates the design value for the sidelobe level.

[0110] 3) Obtain the main lobe gain design value, and calculate the main lobe gain deviation value based on the current main lobe gain value and the main lobe gain design value;

[0111] In the formula, This represents the main lobe gain deviation value. This indicates the current main lobe gain value. This represents the design value for the main lobe gain.

[0112] 4) Calculate the absolute value of beam pointing error, sidelobe level deviation, and main lobe gain deviation using the antenna radiation performance evaluation formula to obtain the antenna radiation performance deviation; The formula for evaluating antenna radiation performance is as follows:

[0113] In the formula, This indicates the deviation in antenna radiation performance. , , This represents the weighting coefficients for each item. This represents the absolute value of the beam pointing error. This indicates the antenna's 3dB beamwidth. This indicates the sidelobe level deviation value. This indicates the design value for the sidelobe level. This represents the main lobe gain deviation value. This represents the design value for the main lobe gain.

[0114] This application provides a phased array antenna deformation compensation method. By monitoring the structural deformation of the antenna panel in real time to obtain antenna structural strain data, and obtaining a real-time strain data vector based on the antenna structural strain data, the target compensation phase vector is accurately calculated based on the real-time strain data vector to perform phase compensation on the antenna array, thereby maintaining the beam pointing accuracy and radiation performance of the phased array antenna in a dynamic environment.

[0115] Based on the foregoing embodiments, this application further provides a phased array antenna deformation compensation system. The modules included in this system can be implemented using a processor in an electronic device; alternatively, they can be implemented using specific logic circuits. During implementation, the processor can be a Central Processing Unit (CPU), a Microprocessor (MPU), a Digital Signal Processor (DSP), or a Field Programmable Gate Array (FPGA), etc.

[0116] like Figure 3 As shown in the figure, this embodiment provides a phased array antenna deformation compensation system. The system includes a distributed strain sensing network 100, a strain data calculation and processing module 200, a beamformer 300, and a performance monitoring and evaluation module 400, wherein: The distributed strain sensing network 100 collects strain data of the antenna structure in real time and sends it to the strain data calculation and processing module 200. The strain data calculation and processing module 200 receives the strain data of the antenna structure, performs preprocessing, and calculates the target compensation phase vector based on the real-time strain data vector obtained from the preprocessing through an objective function, and sends it to the beamformer 300. The beamformer 300 receives the target compensation phase vector calculated by the strain data calculation and processing module 200, superimposes the target compensation phase vector onto the original beamforming phase vector to generate a driving phase vector, and performs phase compensation on the antenna array based on the driving phase vector. After the phase compensation is completed, the performance monitoring and evaluation module 400 acquires the current antenna radiation performance in real time and calculates the antenna radiation performance deviation. If the antenna radiation performance deviation exceeds the preset threshold, the optimization parameters in the objective function are adjusted and sent to the strain data calculation and processing module 200 to recalculate the target compensation phase vector, so as to control the beamformer 300 to perform phase compensation on the antenna array until the antenna radiation performance deviation after phase compensation does not exceed the preset threshold or reaches the preset number of iterations, and then stops, thus completing the antenna deformation compensation.

[0117] In one embodiment, the strain data calculation and processing module 200 includes a data preprocessing unit 210, a deformation reconstruction unit 220, a position deviation calculation unit 230, a phase error calculation unit 240, and a compensation phase vector calculation unit 250, wherein: The data preprocessing unit 210 preprocesses the received antenna structure strain data to obtain a real-time strain data vector and sends it to the deformation reconstruction unit 220. The deformation reconstruction unit 220 calculates the three-dimensional displacement field of the antenna panel in real time based on the received real-time strain data vector and sends it to the position deviation calculation unit 230. The phase error calculation unit 230 calculates the real-time spatial position of each element in the antenna array using an interpolation algorithm based on the received three-dimensional displacement field, and calculates the real-time position deviation of each element based on the real-time spatial position and the ideal stationary position, and sends it to the phase error calculation unit 240. The phase error calculation unit 240 calculates the total phase error vector based on the real-time position deviation of each array element and sends it to the compensation phase vector calculation unit 250. The compensation phase vector calculation unit 250 calculates the target compensation phase vector based on the total phase error vector using an objective function, and sends it to the beamformer 300 via the control bus.

[0118] In one embodiment, a phased array antenna deformation compensation system further includes a communication interface unit, which employs a high-speed serial bus (such as SPI, LVDS or PCIe) or Ethernet communication protocol to ensure low-latency and high-reliability data exchange between the distributed strain sensing network 100, the strain data calculation and processing module 200, the beamformer 300 and the performance monitoring and evaluation module 400.

[0119] The phased array antenna deformation compensation system provided in this application embodiment can form a complete real-time closed-loop compensation link through the above-mentioned units. From strain sensing, deformation reconstruction, phase error calculation to compensation execution and performance evaluation, it realizes adaptive compensation for antenna deformation and significantly improves the beam pointing accuracy and radiation performance of the phased array antenna in dynamic deformation environment.

[0120] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of the invention, the sequence numbers of the above-described processes do not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the invention. The sequence numbers of the above-described embodiments of the invention are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0121] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0122] In the several embodiments provided by this invention, it should be understood that the disclosed methods can be implemented in other ways. The methods disclosed in the several method embodiments provided by this invention can be arbitrarily combined without conflict to obtain new method embodiments. The features disclosed in the several method embodiments provided by this invention can be arbitrarily combined without conflict to obtain new method embodiments.

[0123] The above description is merely an embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for compensating for deformation of a phased array antenna, characterized in that, include: Step S1: Acquire the strain data of the antenna structure collected by the strain sensing network in real time, and preprocess the strain data of the antenna structure to obtain a real-time strain data vector; the strain sensing network consists of multiple strain sensors deployed at the target deployment position of the antenna panel. Step S2: Based on the real-time strain data vector, calculate the three-dimensional displacement field of the antenna panel in real time using the deformation field reconstruction algorithm; Step S3: Based on the three-dimensional displacement field, calculate the real-time spatial position of each element in the antenna array carried by the antenna panel using an interpolation algorithm, and calculate the real-time position deviation of each element based on the real-time spatial position and the ideal static position. Step S4: Calculate the total phase error vector based on the real-time position deviation of each array element; Step S5: Calculate the target compensation phase vector using the objective function based on the total phase error vector; Step S6: Superimpose the target compensation phase vector onto the original beamforming phase vector to generate a driving phase vector, and perform phase compensation on the antenna array based on the driving phase vector; Step S7: After the phase compensation is completed, the current antenna radiation performance is obtained in real time and the antenna radiation performance deviation is calculated. If the antenna radiation performance deviation exceeds the preset threshold, the optimization parameters in the objective function are adjusted and steps S5 to S7 are repeated until the antenna radiation performance deviation does not exceed the preset threshold or the preset number of iterations is reached, and the antenna deformation compensation is completed.

2. The phased array antenna deformation compensation method according to claim 1, characterized in that, The preprocessing of the antenna structure strain data to obtain a real-time strain data vector includes: The strain data of the antenna structure are demodulated, and the demodulated analog signal is converted into the original digital signal. The original digital signal is filtered by a low-pass filter, and temperature compensation is performed on the filtered digital signal to obtain the compensation strain vector. Outlier detection and removal are performed on the compensation strain values ​​in the compensation strain vector to obtain the effective strain vector; By associating each element of the effective strain vector with the spatial coordinates of the corresponding sensor, a real-time strain data vector is obtained.

3. The phased array antenna deformation compensation method according to claim 1, characterized in that, The step of calculating the three-dimensional displacement field of the antenna panel in real time based on the real-time strain data vector using a deformation field reconstruction algorithm includes: The real-time estimated deformation is determined based on the real-time strain data vector, and the deformation threshold is determined based on the antenna operating wavelength. When the real-time estimated deformation is less than the deformation threshold, the modal superposition method is selected as the deformation field reconstruction algorithm to calculate the three-dimensional displacement field of the antenna panel in real time. When the real-time estimated deformation is greater than or equal to the deformation threshold, the finite element inversion method is selected as the deformation field reconstruction algorithm to calculate the three-dimensional displacement field of the antenna panel in real time.

4. The phased array antenna deformation compensation method according to claim 3, characterized in that, The selected mode superposition method, used as the deformation field reconstruction algorithm, calculates the three-dimensional displacement field of the antenna panel in real time, including: Obtain the structural modal shape matrix calculated from the finite element analysis model, and the strain-displacement relationship matrix composed of the partial derivatives of the finite element shape functions with respect to spatial coordinates; A modal strain matrix is ​​constructed based on the structural mode shape matrix and the strain-displacement relationship matrix. The real-time strain data vector and the modal strain matrix are processed by the least squares method to obtain the real-time modal coordinate vector; Based on the real-time modal coordinate vector and the structural modal shape matrix, the three-dimensional displacement field of the antenna panel is calculated in real time.

5. The phased array antenna deformation compensation method according to claim 3, characterized in that, The selection of the finite element inversion method as the deformation field reconstruction algorithm for real-time calculation of the three-dimensional displacement field of the antenna panel includes: Obtain the regularization matrix calculated from the finite element analysis model and the strain-displacement relationship matrix composed of the partial derivatives of the finite element shape functions with respect to spatial coordinates; The optimal regularization coefficient is selected from the candidate set of regularization coefficients using the L-curve method or the generalized cross-validation method. Based on the strain-displacement relationship matrix, the optimal regularization coefficient, the regularization matrix, and the real-time strain data vector, a regularization coefficient matrix and a strain projection equivalent vector are constructed. The three-dimensional displacement field of the antenna panel is calculated in real time based on the regularization coefficient matrix, the strain projection equivalent vector, and the real-time strain data vector.

6. The phased array antenna deformation compensation method according to claim 1, characterized in that, The calculation of the total phase error vector based on the real-time position deviation of each array element includes: The real-time geometric phase error of each array element is calculated by the dot product of the real-time position deviation of each array element and the beam pointing unit vector. The antenna array is determined to be operating in the near field region based on the real-time position deviation of each element and the Rayleigh distance. If it is operating in the near field region, the real-time near field correction is calculated based on the real-time position deviation of each element. Based on the real-time position deviation and ideal position of each array element, the real-time change in the spacing between array elements before and after deformation is calculated. The mutual impedance change is obtained by querying the mutual coupling coefficient lookup table based on the real-time change of the array element spacing, and the real-time mutual coupling phase correction of each array element is calculated based on the mutual impedance change. The total phase error vector is obtained based on the real-time geometric phase error, real-time near-field correction, and real-time mutual coupling phase correction of all array elements.

7. The phased array antenna deformation compensation method according to claim 1, characterized in that, Based on the total phase error vector, the target compensation phase vector is calculated using the objective function, including: When the antenna array control system is in the first working mode, the total phase error vector is processed according to the reference zero elimination method to construct the first objective function and obtain the initial compensation phase vector. When the antenna array control system is in the second operating mode, the total phase error vector is processed according to the minimum mean square error method to construct a second objective function, and the second objective function is minimized under the phase shifter quantization accuracy to obtain the initial compensation phase vector; the first operating mode is more sensitive to compensation speed than to compensation accuracy, and the second operating mode is more sensitive to compensation accuracy than to compensation speed. The initial compensation phase vector is subjected to time smoothing constraint processing to obtain a smooth compensation phase vector; The target compensation phase vector is obtained by determining the quantization step size by the number of phase shifter bits and constraining the smooth compensation phase.

8. The phased array antenna deformation compensation method according to claim 7, characterized in that, The current antenna radiation performance includes the current beam pointing angle, the current sidelobe level, and the current main lobe gain. The calculation of antenna radiation performance deviation includes: Obtain the ideal beam pointing angle, and calculate the absolute value of the beam pointing error based on the current beam pointing angle and the ideal beam pointing angle; Obtain the sidelobe level design value, and calculate the sidelobe level deviation value based on the current sidelobe level value and the sidelobe level design value; Obtain the main lobe gain design value, and calculate the main lobe gain deviation value based on the current main lobe gain value and the main lobe gain design value; The antenna radiation performance deviation is obtained by calculating the absolute value of the beam pointing error, the sidelobe level deviation, and the main lobe gain deviation using the antenna radiation performance evaluation formula. The antenna radiation performance evaluation formula is as follows: In the formula, This indicates the deviation in antenna radiation performance. , , This represents the weighting coefficients for each item. This represents the absolute value of the beam pointing error. This indicates the antenna's 3dB beamwidth. This indicates the sidelobe level deviation value. This indicates the design value for the sidelobe level. This represents the main lobe gain deviation value. This represents the design value for the main lobe gain.

9. A phased array antenna deformation compensation system, characterized in that, The system includes a distributed strain sensing network, a strain data calculation and processing module, a beamformer, and a performance monitoring and evaluation module, wherein: The distributed strain sensing network collects antenna structure strain data in real time and sends it to the strain data calculation and processing module. After receiving the strain data of the antenna structure, the strain data calculation and processing module performs preprocessing, and based on the real-time strain data vector obtained from the preprocessing, calculates the target compensation phase vector through the objective function and sends it to the beamformer. The beamformer receives the target compensation phase vector calculated by the strain data calculation and processing module, superimposes the target compensation phase vector onto the original beamforming phase vector to generate a driving phase vector, and performs phase compensation on the antenna array based on the driving phase vector. The performance monitoring and evaluation module acquires the current antenna radiation performance in real time and calculates the antenna radiation performance deviation after the phase compensation is completed. If the antenna radiation performance deviation exceeds a preset threshold, the optimization parameters in the objective function are adjusted and sent to the strain data calculation and processing module to recalculate the target compensation phase vector in order to control the beamformer to perform phase compensation on the antenna array until the antenna radiation performance deviation after phase compensation does not exceed the preset threshold or reaches the preset number of iterations, thus completing the antenna deformation compensation.

10. A phased array antenna deformation compensation system according to claim 9, characterized in that, The strain data calculation and processing module includes a data preprocessing unit, a deformation reconstruction unit, a position deviation calculation unit, a phase error calculation unit, and a compensation phase vector calculation unit, wherein: The data preprocessing unit preprocesses the received antenna structure strain data to obtain a real-time strain data vector and sends it to the deformation reconstruction unit. The deformation reconstruction unit calculates the three-dimensional displacement field of the antenna panel in real time based on the received real-time strain data vector using a deformation field reconstruction algorithm and sends it to the position deviation calculation unit. The phase error calculation unit calculates the real-time spatial position of each element in the antenna array using an interpolation algorithm based on the received three-dimensional displacement field, and calculates the real-time position deviation of each element based on the real-time spatial position and the ideal stationary position, and sends it to the phase error calculation unit. The phase error calculation unit calculates the total phase error vector based on the real-time position deviation of each array element and sends it to the compensation phase vector calculation unit. The compensation phase vector calculation unit calculates the target compensation phase vector based on the total phase error vector using an objective function, and sends it to the beamformer via the control bus.

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