MIMO-SAR target vibration parameter resolving method and system

Abstract

The invention provides an MIMO-SAR target vibration parameter resolving method and system, and belongs to the technical field of vibration monitoring, and the method comprises the steps: obtaining the original echo data of MIMO-SAR, carrying out the sub-aperture division of the original echo data, and obtaining the original echo data corresponding to each sub-aperture; determining an included angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the position relationship between the target and the phase center of the synthetic aperture; the target is a preset monitoring point of the MIMO-SAR; obtaining a phase difference between every two adjacent sub-apertures based on the original echo data corresponding to each sub-aperture; and based on the included angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference of every two adjacent sub-apertures, constructing a target function, and resolving the target function to obtain a target vibration parameter. The method can improve the precise estimation of the target vibration parameters, and improves the deformation monitoring precision and health detection capability of a large-scale structure.

Description

Technical Field

[0001] The present application belongs to the field of vibration monitoring technology, and more specifically, relates to a MIMO-SAR target vibration parameter solution method and system. Background Art

[0002] Multiple Input Multiple Output Synthetic Aperture Radar (MIMO-SAR) can achieve submillimeter deformation measurement accuracy. Its advantages include non-contact, all-weather, and high-resolution performance. It is suitable for deformation or vibration monitoring of large structures such as satellite antennas, bridges, and industrial equipment. However, a single MIMO-SAR can only capture a one-dimensional projection of the target's deformation along the radar's line of sight, making it difficult to fully characterize the target's true deformation evolution. Therefore, accurately estimating target vibration parameters using a single MIMO-SAR is a pressing issue. Summary of the Invention

[0003] The purpose of this application is to provide a MIMO-SAR target vibration parameter solution method and system to improve the accurate estimation of target vibration parameters and enhance the deformation monitoring accuracy and health detection capability of large structures such as satellite antenna structures, bridges, and industrial equipment.

[0004] A first aspect of an embodiment of the present application provides a method for calculating MIMO-SAR target vibration parameters, comprising: Obtaining original echo data of MIMO-SAR, dividing the original echo data into sub-apertures, and obtaining original echo data corresponding to each sub-aperture; Determining the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the positional relationship between the phase center of the target and the synthetic aperture; the target being a preset monitoring point of the MIMO-SAR; The phase difference between each two adjacent sub-apertures is obtained based on the original echo data corresponding to each sub-aperture; Based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference between each two adjacent sub-apertures, an objective function is constructed, and the objective function is solved to obtain target vibration parameters, which include at least one of the vibration direction angle, vibration frequency, vibration phase and vibration amplitude.

[0005] A second aspect of the embodiments of the present application provides a MIMO-SAR target vibration parameter solution system, comprising: The sub-aperture division module is used to obtain the original echo data of MIMO-SAR, divide the original echo data into sub-apertures, and obtain the original echo data corresponding to each sub-aperture; An angle determination module, configured to determine an angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on a positional relationship between the phase centers of a target and the synthetic aperture; the target being a preset monitoring point of the MIMO-SAR; A phase difference calculation module is used to obtain the phase difference between every two adjacent sub-apertures based on the original echo data corresponding to each sub-aperture; A solution module is used to construct an objective function based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference between each two adjacent sub-apertures, and to solve the objective function to obtain target vibration parameters, wherein the target vibration parameters include at least one of the vibration direction angle, vibration frequency, vibration phase and vibration amplitude.

[0006] In a third aspect of an embodiment of the present application, an electronic device is provided, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the steps of the above-mentioned method for solving MIMO-SAR target vibration parameters are implemented.

[0007] According to a fourth aspect of the embodiments of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above-mentioned method for solving MIMO-SAR target vibration parameters are implemented.

[0008] The beneficial effects of the MIMO-SAR target vibration parameter calculation method and system provided in the embodiments of the present application are: This application divides the original echo data into sub-apertures to analyze the echo characteristics more carefully and provide a more accurate data basis for subsequent processing. Secondly, the angle is determined based on the positional relationship between the target and the synthetic aperture phase center, and the phase difference between adjacent sub-apertures is obtained using the original echo data of each sub-aperture, and the target function is constructed for solution. This comprehensive use of multi-dimensional information significantly improves the accuracy of the target vibration parameter solution. The calculated parameters such as vibration direction angle, vibration frequency, vibration phase and vibration amplitude can comprehensively and accurately describe the target vibration state. Therefore, this application can improve the accurate estimation of target vibration parameters and improve the deformation monitoring accuracy and health detection capabilities of large structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0010] Figure 1 A flowchart of a method for calculating MIMO-SAR target vibration parameters according to an embodiment of the present application is provided; Figure 2 The sub-aperture division diagram provided for this application; Figure 3 Schematic diagram of the angle between the MIMO-SAR sight line direction and the target vibration direction, as well as the angle between the array sight line direction, provided in this application; Figure 4 This is a structural block diagram of a MIMO-SAR target vibration parameter solution system provided in one embodiment of the present application; Figure 5 A schematic block diagram of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0011] In the following description, specific details such as specific system structures and techniques are provided for purposes of illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obscuring the description of the present application with unnecessary detail.

[0012] In order to make the purpose, technical solutions and advantages of this application clearer, specific embodiments will be described below with reference to the accompanying drawings.

[0013] Please refer to Figure 1 , Figure 1 This is a flow chart of a method for calculating MIMO-SAR target vibration parameters provided in one embodiment of the present application, and Figure 1 As a possible embodiment, the method includes: S101: Acquire original echo data of MIMO-SAR, divide the original echo data into sub-apertures, and obtain original echo data corresponding to each sub-aperture.

[0014] In this embodiment, a MIMO-SAR (i.e., radar) transmits an electromagnetic wave signal. Upon encountering a monitored target, the target reflects some of the electromagnetic wave back to the radar. The reflected signal received by the radar is the raw echo data. This raw echo data contains various information, such as the target's range, speed, and direction. However, this information is mixed and requires further processing to extract useful information.

[0015] Subaperture partitioning involves dividing the entire aperture of a synthetic aperture radar into multiple smaller apertures according to specific rules. These smaller apertures are called subapertures. This embodiment utilizes subaperture partitioning to observe a target from different angles, thereby obtaining more information about the target. Specifically, this embodiment performs subaperture partitioning on a single MIMO-SAR radar, estimating the target's true deformation and orientation based on the one-dimensional line-of-sight deformation of multiple subapertures. This allows a single radar to measure the target's true deformation and orientation. Furthermore, this embodiment performs subaperture partitioning on the raw echo data of the MIMO-SAR radar, obtaining raw echo data corresponding to each subaperture for subsequent processing and calculation.

[0016] In this example, the target can be a sinusoidal vibration: ; in, is the amplitude, is the vibration frequency, is the initial phase.

[0017] In this embodiment, after the original echo data is divided into sub-apertures to obtain the original echo data corresponding to each sub-aperture, a MIMO-SAR target vibration parameter solution method further includes: The phase center of each sub-aperture is determined according to the equivalent phase center principle.

[0018] The equivalent phase center principle states that in a synthetic aperture radar (SAR), echo signals received at different locations are equivalent to signals transmitted and received from a single, specific point: the equivalent phase center. This principle, based on the phase characteristics of radar echo signals, simplifies the complex radar aperture reception process into one of receiving signals from the equivalent phase center through mathematical derivation and signal processing, facilitating analysis and processing.

[0019] For each divided sub-aperture, according to the equivalent phase center principle, by calculating the phase characteristics, propagation distance and other parameters of the echo signal within the sub-aperture, a point representing the equivalent transmission and reception position of the sub-aperture is determined, namely the phase center.

[0020] For example, the phase center of each sub-aperture is determined according to the equivalent phase center principle, and the specific division is as follows: Figure 2As shown in the figure, each sub-aperture has 29 array elements, and the middle array element is taken as the center point of each sub-aperture, that is, the center array element of sub-aperture 1 is 15, and the center array element of sub-aperture 2 is 44.

[0021] When MIMO-SAR is operating, the transmitting antenna transmits a signal, which is reflected by the target and then received by the receiving antenna, forming raw echo data. Subaperture partitioning utilizes the principle of equivalent phase center. By dividing the raw echo data into different dimensions (time, space, and frequency), each subaperture becomes an independent small radar, "observing" the target from different angles. The data from different subapertures contains information about the scattering of the target at different angles. This data can then be used to more accurately calculate target parameters, such as the target's vibration direction angle. For example, when monitoring small vibrations in a large building, the raw echo data reflects the reflection of the radar signal from the building as a whole. After subaperture partitioning, the raw echo data from different subapertures reflects the reflection characteristics of different local areas of the building. By comparing and analyzing the raw echo data from these subapertures, more accurate information about the building's vibrations can be obtained.

[0022] S102: Determine the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on a positional relationship between the target and the phase center of the synthetic aperture; the target is a preset monitoring point of the MIMO-SAR.

[0023] In this embodiment, the target is a preset monitoring point of the MIMO-SAR. The phase center of the synthetic aperture is the equivalent phase center after the multiple sub-aperture signals are synthesized, and is located at the geometric center of the array.

[0024] In this embodiment, if original echo data corresponding to two sub-apertures are obtained after sub-aperture division, the two sub-apertures include: a first sub-aperture and a second sub-aperture.

[0025] The angle between the phase center of the synthetic aperture and the phase center of each sub-aperture is determined based on the positional relationship between the target and the synthetic aperture, including: determining a first distance based on a positional relationship between a phase center of the first sub-aperture and a phase center of the second sub-aperture; Determining a second distance based on a positional relationship between the target and the phase center of the synthetic aperture, the second distance being the distance between the target and the phase center of the synthetic aperture; An angle between a phase center of the synthetic aperture and a phase center of each sub-aperture is determined based on the first distance and the second distance.

[0026] Specifically, determining the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the first distance and the second distance includes: Determining the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the first formula; The first formula is: ; in, is the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture; is the first distance, is the second distance.

[0027] In this embodiment, Figure 3 The positions of the first and second distances can be seen in the figure. Since the unit conversion formula is ; The first formula can be simplified to obtain: radians or degrees; among them, is the ratio of the second distance to the first distance, when The error is less than 0.1%.

[0028] S103: Obtaining the phase difference between every two adjacent sub-apertures based on the original echo data corresponding to each sub-aperture.

[0029] In this embodiment, the raw echo data includes echo signals. The difference in phase between the echo signals received by two adjacent sub-apertures is the phase difference between the two adjacent sub-apertures. Phase is a physical quantity that describes the state of a periodic signal at a given moment. Due to the different positions of adjacent sub-apertures, the echo signals received differ in propagation paths and timing, resulting in different phases. The difference between these two phases is the phase difference.

[0030] The original echo data can be converted into single-view complex images in the distance and direction dimensions through Fast Fourier Transform (FFT). The interferometric phase of the target can be obtained by performing conjugate multiplication on the complex echo signals of the same target.

[0031] Specifically, the phase difference between each two adjacent sub-apertures is obtained based on the original echo data corresponding to each sub-aperture, including: The phase difference between two adjacent sub-apertures is calculated based on the second formula and recorded as the first phase difference; The second formula is:

[0032] in, is the first phase difference, is the interference phase of the first subaperture, is the interference phase of the second sub-aperture. The interference phase of the first sub-aperture is obtained based on the original echo data corresponding to the first sub-aperture, and the interference phase of the second sub-aperture is obtained based on the original echo data corresponding to the second sub-aperture.

[0033] S104: Based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference between each two adjacent sub-apertures, construct a target function, solve the target function, and obtain target vibration parameters. The target vibration parameters include at least one of the vibration direction angle, vibration frequency, vibration phase and vibration amplitude.

[0034] In this embodiment, the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture can be used to construct a phase difference using trigonometric identities, and the phase difference between each two adjacent sub-apertures is calculated based on the original echo data corresponding to each sub-aperture. The above two phase difference calculation formulas can construct the objective function.

[0035] The objective function is a mathematical function constructed to solve for unknown parameters such as the target vibration azimuth angle. It links the phase difference constructed using trigonometric identities with the phase difference calculated based on the raw echo data corresponding to each subaperture. By adjusting the unknown parameters in the function, the function value is optimally matched to the actual observed data, thereby achieving an estimation of the target vibration parameters.

[0036] The target vibration azimuth angle represents the angle between the target vibration direction and a specific reference direction (such as the radar line of sight). It is a key parameter describing the target vibration direction and is accurately determined by solving the objective function. This embodiment solves the objective function to essentially find a set of parameters (with the target vibration azimuth angle as one of the key parameters) that ensures that the phase difference calculated by the model is as close as possible to the actual observed phase difference, thereby achieving a precise solution for the target vibration azimuth angle.

[0037] From the above, it can be concluded that the present application can analyze the echo characteristics more carefully by dividing the original echo data into sub-apertures, providing a more accurate data basis for subsequent processing. Secondly, the angle is determined based on the positional relationship between the target and the synthetic aperture phase center, and the phase difference between adjacent sub-apertures is obtained using the original echo data of each sub-aperture, and the objective function is constructed for solution. This comprehensive use of multi-dimensional information significantly improves the accuracy of the target vibration parameter solution. The calculated parameters such as vibration direction angle, vibration frequency, vibration phase and vibration amplitude can comprehensively and accurately describe the target vibration state. Therefore, the present application can improve the accurate estimation of target vibration parameters and improve the deformation monitoring accuracy and health detection capabilities of large structures.

[0038] In one embodiment of the present application, determining the objective function based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference between two adjacent sub-apertures includes: determining a second phase difference based on an angle between a phase center of the synthetic aperture and a phase center of each sub-aperture; An objective function is constructed based on the second phase difference and the first phase difference.

[0039] In this embodiment, Figure 3 Schematic diagram of the angle between the MIMO-SAR line of sight and the target vibration direction, as well as the angle between the array line of sight. The angle between the phase center of the synthetic aperture and the phase center of each sub-aperture can be expressed as follows: The angle between the second sub-aperture line of sight and the target vibration direction is , recorded as the first angle; the angle between the first sub-aperture sight line direction and the target vibration direction is , recorded as the second angle; where, is the angle between the target vibration direction and the radar line of sight, and the angle between the synthetic aperture phase center and the subaperture phase center is .

[0040] The target vibration displacement is , the projection of the target vibration displacement in the line of sight direction of each sub-aperture is ; Determining a second phase difference based on an angle between a phase center of the synthetic aperture and a phase center of each sub-aperture includes: determining a second phase difference based on a third formula; The third formula is:

[0041] in, is the radar wavelength, is the angle between the target vibration direction and the radar line of sight, is the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture; is the vibration displacement of the target, For time.

[0042] Specifically, the specific steps for calculating the second phase difference are as follows:

[0043] The first angle and the second angle Substituting into the above formula and using the trigonometric identities:

[0044] You can get:

[0045] in, is the speed of light, is the radar frequency, is the radar wavelength.

[0046] Afterwards, an objective function can be constructed based on the second phase difference and the first phase difference for subsequent calculation of target vibration parameters.

[0047] As can be seen from the above, this embodiment not only takes into account the projection of the target vibration displacement on the line of sight of each sub-aperture, but also calculates the phase difference between adjacent sub-apertures based on the angle between each sub-aperture's line of sight and the target vibration direction, providing more reliable phase information. Furthermore, by simplifying the formula and introducing the angle factor, the accuracy of the phase difference calculation is further improved, making the ultimately calculated target vibration parameters more precise. Therefore, this embodiment enhances the effectiveness and reliability of MIMO-SAR in processing target vibration parameter solutions.

[0048] In one embodiment of the present application, the constructed objective function is:

[0049] in, is the first phase difference, is the second phase difference, For time.

[0050] In this embodiment, the target vibration parameter includes at least one of the vibration direction angle, vibration frequency, vibration phase and vibration amplitude, that is, , , , All four parameters are unknown and need to be solved jointly through multi-time echo data. Therefore, according to the target vibration parameters to be solved, the objective function can be constructed as follows:

[0051] in, is the first phase difference, is the phase difference estimated according to the objective function, is the estimated target vibration, is the estimated target vibration direction angle, For time, is the target vibration amplitude, is the target vibration frequency, is the initial phase of target vibration, The target vibration amplitude estimated by the objective function, The target vibration frequency estimated by the objective function, The initial phase of the target vibration estimated by the estimation function.

[0052] In this embodiment, the objective function is solved to obtain the target vibration parameters, including: The objective function is solved based on the nonlinear least squares method to obtain the target vibration parameters.

[0053] In this embodiment, nonlinear least squares iterative optimization is used to solve , , ( can be represented by these three parameters) and This function achieves high-precision joint estimation of vibration direction angle, frequency, phase and amplitude by minimizing the difference between observation and model.

[0054] The objective function is a mathematical expression that relates related quantities, such as the first phase difference and the second phase difference. This embodiment adjusts the unknown parameters in the objective function to achieve an optimal match between the function value and the actual observed data, thereby obtaining an estimate of parameters such as the target vibration direction angle. The objective function is typically constructed in the form of an error, for example, minimizing the difference between the observed value and the theoretically calculated value.

[0055] Nonlinear least squares is an optimization algorithm used when the problem involves nonlinear functions and the goal is to minimize the sum of squared errors in a set of data. Nonlinear least squares works by iteratively adjusting the unknown parameters of the function, gradually reducing the error until certain convergence conditions are met and the optimal solution is obtained.

[0056] Specifically, the steps of this embodiment are as follows: First, initialize the parameters. Before using nonlinear least squares to solve the objective function, it's necessary to set initial values for the target vibration parameters. These initial values can be determined based on experience, simple initial measurements, or theoretical estimates, but they are only preliminary guesses and will be continuously optimized through the algorithm.

[0057] Second, calculate the objective function value. Substitute the initialized parameters into the objective function. Based on the objective function's specific expression and the calculation formulas for the first and second phase differences, calculate the objective function value for the current parameters. This value reflects the degree of match between the current parameters and the actual observed data. The smaller the function value, the closer the parameter is to the true value.

[0058] Third, iterative optimization. Based on the principles of nonlinear least squares, the objective function is used to adjust the current parameters. The iterations take into account the objective function's gradient (i.e., the rate of change of the function value with changes in the parameters) and update the parameters in a direction that reduces the objective function value. Each iteration continuously optimizes the parameters based on the parameter values obtained in the previous iteration, gradually reducing the objective function value.

[0059] Fourth, after each iteration, check whether the preset convergence criteria are met. This convergence criterion can be that the change in the objective function value is less than a certain minimum value (such as 0.0001), or that the change in a parameter is less than a certain threshold. If the convergence criteria are met, the algorithm has found a relatively ideal solution, and the iteration stops. If not, the algorithm continues to the next iteration.

[0060] Fifth, the target vibration parameters are obtained. When the algorithm converges, the obtained parameter values are the optimal estimates of the target vibration angle and other related parameters. The target vibration angle is extracted from these parameters, which is the final result obtained by solving the objective function.

[0061] As can be seen from the above, this embodiment uses nonlinear least squares iterative optimization to improve the accuracy and stability of the objective function solution, thereby accurately obtaining the target vibration parameters. This embodiment effectively improves the performance of the MIMO-SAR system when processing target vibration parameter solution.

[0062] Corresponding to a MIMO-SAR target vibration parameter solution method in the above embodiment, Figure 4 This is a structural block diagram of a MIMO-SAR target vibration parameter solution system provided in one embodiment of the present application. For ease of explanation, only the parts related to the embodiment of the present application are shown. Figure 4 The MIMO-SAR target vibration parameter calculation system 20 includes: a sub-aperture division module 21, an angle determination module 22, a phase difference calculation module 23 and a calculation module 24.

[0063] The sub-aperture division module 21 is used to obtain the original echo data of the MIMO-SAR, divide the original echo data into sub-apertures, and obtain the original echo data corresponding to each sub-aperture; An angle determination module 22 is used to determine the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the positional relationship between the phase center of the target and the synthetic aperture; the target is a preset monitoring point of the MIMO-SAR; A phase difference calculation module 23 is configured to obtain the phase difference between each two adjacent sub-apertures based on the original echo data corresponding to each sub-aperture; The solution module 24 is used to construct a target function based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference between each two adjacent sub-apertures, and to solve the target function to obtain target vibration parameters, where the target vibration parameters include at least one of the vibration direction angle, vibration frequency, vibration phase and vibration amplitude.

[0064] In one embodiment of the present application, if original echo data corresponding to two sub-apertures are obtained after sub-aperture division, the two sub-apertures include: a first sub-aperture and a second sub-aperture; The angle determination module 22 is specifically configured to determine the first distance based on the positional relationship between the phase center of the first sub-aperture and the phase center of the second sub-aperture; Determining a second distance based on a positional relationship between the target and the phase center of the synthetic aperture, the second distance being the distance between the target and the phase center of the synthetic aperture; An angle between a phase center of the synthetic aperture and a phase center of each sub-aperture is determined based on the first distance and the second distance.

[0065] In one embodiment of the present application, the angle determination module 22 is further configured to determine the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the first formula; The first formula is: ; in, is the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture; is the first distance, is the second distance.

[0066] In one embodiment of the present application, the phase difference calculation module 23 is specifically configured to calculate the phase difference between two adjacent sub-apertures based on the second formula, which is recorded as the first phase difference; The second formula is:

[0067] in, is the first phase difference, is the interference phase of the first subaperture, is the interference phase of the second sub-aperture. The interference phase of the first sub-aperture is obtained based on the original echo data corresponding to the first sub-aperture, and the interference phase of the second sub-aperture is obtained based on the original echo data corresponding to the second sub-aperture.

[0068] In one embodiment of the present application, the solving module 24 is specifically configured to determine the second phase difference based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture; An objective function is constructed based on the second phase difference and the first phase difference.

[0069] In one embodiment of the present application, the solving module 24 is further configured to determine the second phase difference based on the third formula; The third formula is:

[0070] in, is the radar wavelength, is the angle between the target vibration direction and the radar line of sight, is the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture; is the vibration displacement of the target, For time.

[0071] In one embodiment of the present application, the constructed objective function is:

[0072] in, is the first phase difference, is the second phase difference, For time.

[0073] See also Figure 5 , Figure 5 This is a schematic block diagram of an electronic device provided in one embodiment of the present application. Figure 5 The electronic device 300 in the embodiment shown may include: one or more processors 301, one or more input devices 302, one or more output devices 303, and one or more memories 304. The processors 301, input devices 302, output devices 303, and memories 304 communicate with each other via a communication bus 305. The memory 304 is used to store computer programs, which include program instructions. The processor 301 is used to execute the program instructions stored in the memory 304. The processor 301 is configured to call the program instructions to execute the functions of the modules / units in the above-mentioned system embodiments, such as Figure 4 The functions of the sub-aperture division module 21, the angle determination module 22, the phase difference calculation module 23 and the solution module 24 are shown.

[0074] It should be understood that in the embodiments of the present application, the processor 301 may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0075] The input device 302 may include a touchpad, a fingerprint collection sensor (for collecting user fingerprint information and fingerprint direction information), a microphone, etc. The output device 303 may include a display (LCD, etc.), a speaker, etc.

[0076] The memory 304 may include a read-only memory and a random access memory, and provides instructions and data to the processor 301. A portion of the memory 304 may also include a non-volatile random access memory. For example, the memory 304 may also store device type information.

[0077] In a specific implementation, the processor 301, input device 302, and output device 303 described in the embodiment of the present application can execute the implementation method described in the embodiment of a MIMO-SAR target vibration parameter solution method provided in the embodiment of the present application, and can also execute the implementation method of the electronic device described in the embodiment of the present application, which will not be repeated here.

[0078] In another embodiment of the present application, a computer-readable storage medium is provided. The computer-readable storage medium stores a computer program. The computer program includes program instructions. When the program instructions are executed by a processor, all or part of the process of the method in the above embodiment is implemented. The computer program can also be used to instruct related hardware to complete the process. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of each of the above method embodiments are implemented. The computer program includes computer program code, which can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium.

[0079] The computer-readable storage medium can be an internal storage unit of the electronic device in any of the aforementioned embodiments, such as a hard disk or memory of the electronic device. The computer-readable storage medium can also be an external storage device of the electronic device, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a flash memory card, etc. Furthermore, the computer-readable storage medium can include both an internal storage unit of the electronic device and an external storage device. The computer-readable storage medium is used to store computer programs and other programs and data required by the electronic device. The computer-readable storage medium can also be used to temporarily store data that has been output or is about to be output.

[0080] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0081] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the electronic devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0082] In the several embodiments provided in this application, it should be understood that the disclosed electronic devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces or units, or can be an electrical, mechanical or other form of connection.

[0083] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0084] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0085] The above are only specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and such modifications or substitutions should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A MIMO-SAR target vibration parameter solution method, characterized in that: include: Obtaining original echo data of MIMO-SAR, dividing the original echo data into sub-apertures, and obtaining original echo data corresponding to each sub-aperture; Determining the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the positional relationship between the phase center of the target and the synthetic aperture; the target being a preset monitoring point of the MIMO-SAR; The phase difference between each two adjacent sub-apertures is obtained based on the original echo data corresponding to each sub-aperture; Based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference between each two adjacent sub-apertures, an objective function is constructed, and the objective function is solved to obtain target vibration parameters, which include at least one of the vibration direction angle, vibration frequency, vibration phase and vibration amplitude.

2. A MIMO-SAR target vibration parameter solution method as claimed in claim 1, characterized in that: If original echo data corresponding to two sub-apertures are obtained after sub-aperture division, the two sub-apertures include: a first sub-aperture and a second sub-aperture; The step of determining the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the positional relationship between the target and the synthetic aperture includes: determining a first distance based on a positional relationship between a phase center of the first sub-aperture and a phase center of the second sub-aperture; determining a second distance based on a positional relationship between the target and the phase center of the synthetic aperture, the second distance being the distance between the target and the phase center of the synthetic aperture; Based on the first distance and the second distance, an angle between the phase center of the synthetic aperture and the phase center of each sub-aperture is determined.

3. A MIMO-SAR target vibration parameter solution method as claimed in claim 2, characterized in that: The determining, based on the first distance and the second distance, an angle between the phase center of the synthetic aperture and the phase center of each sub-aperture includes: Determining the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on the first formula; The first formula is: ; in, is the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture; is the first distance, is the second distance.

4. A MIMO-SAR target vibration parameter solution method as claimed in claim 2, characterized in that: The phase difference between each two adjacent sub-apertures is obtained based on the original echo data corresponding to each sub-aperture, including: Calculate the phase difference between the two adjacent sub-apertures based on the second formula, and record it as the first phase difference; The second formula is: in, is the first phase difference, is the interference phase of the first subaperture, is the interference phase of the second sub-aperture, the interference phase of the first sub-aperture is obtained based on the original echo data corresponding to the first sub-aperture, and the interference phase of the second sub-aperture is obtained based on the original echo data corresponding to the second sub-aperture.

5. A MIMO-SAR target vibration parameter solution method as claimed in claim 4, characterized in that: The determining of the objective function based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference between the two adjacent sub-apertures includes: determining a second phase difference based on an angle between a phase center of the synthetic aperture and a phase center of each sub-aperture; An objective function is constructed based on the second phase difference and the first phase difference.

6. A MIMO-SAR target vibration parameter solution method as claimed in claim 5, characterized in that: The determining the second phase difference based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture includes: determining a second phase difference based on a third formula; The third formula is: in, is the radar wavelength, is the angle between the target vibration direction and the radar line of sight, is the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture; is the vibration displacement of the target, For time.

7. A MIMO-SAR target vibration parameter calculation method as claimed in claim 6, characterized in that: The constructed objective function is: in, is the first phase difference, is the second phase difference, For time.

8. A MIMO-SAR target vibration parameter calculation system, characterized in that: include: The sub-aperture division module is used to obtain the original echo data of MIMO-SAR, divide the original echo data into sub-apertures, and obtain the original echo data corresponding to each sub-aperture; An angle determination module, configured to determine an angle between the phase center of the synthetic aperture and the phase center of each sub-aperture based on a positional relationship between the phase centers of a target and the synthetic aperture; the target being a preset monitoring point of the MIMO-SAR; A phase difference calculation module is used to obtain the phase difference between every two adjacent sub-apertures based on the original echo data corresponding to each sub-aperture; A solution module is used to construct an objective function based on the angle between the phase center of the synthetic aperture and the phase center of each sub-aperture and the phase difference between each two adjacent sub-apertures, and to solve the objective function to obtain target vibration parameters, wherein the target vibration parameters include at least one of the vibration direction angle, vibration frequency, vibration phase and vibration amplitude.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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