A target motion parameter estimation method, device, storage medium and equipment

Abstract

The application provides a target motion parameter estimation method and device, a storage medium and equipment. In the method, echoes of a target are divided into multiple sub-aperture echoes, each sub-aperture echo is subjected to GRFT processing, sub-aperture GRFT results corresponding to each sub-aperture echo are obtained, all sub-aperture GRFT results are fused into full-aperture GRFT results, and the motion parameters of the target are estimated based on the full-aperture GRFT results. In this way, the order of the parameter search space in the sub-aperture is reduced and the search step of the parameter is increased through the sub-aperture technology, thereby reducing the computation amount of the GRFT. Finally, the target motion parameter estimation is completed through the sub-aperture fusion, and the estimation efficiency is effectively improved while the estimation accuracy is ensured.

Description

Technical Field

[0001] This application relates to the field of motion parameter estimation technology, and more specifically, to a method, apparatus, storage medium, and device for estimating target motion parameters. Background Technology

[0002] Synthetic Aperture Radar (SAR) is an active microwave remote sensing device mounted on mobile platforms such as aircraft or satellites. Radar imaging of moving targets on the sea surface is an important branch of SAR imaging technology. The Range-Instantaneous Doppler (RID) imaging algorithm based on the Generalized Radon Fourier Transform (GRFT) is a typical algorithm for imaging moving targets on the sea surface. It accurately estimates the motion parameters of each scattering point of a moving target in the echo using GRFT, thereby obtaining a range-instantaneous Doppler image. This method is applicable to imaging non-stationary moving targets under low signal-to-noise ratio and complex sea conditions. However, the traditional GRFT method has a high computational cost, resulting in low efficiency in estimating target motion parameters. Summary of the Invention

[0003] The purpose of this application is to provide a method, apparatus, storage medium and device for estimating target motion parameters, in order to solve the problem that the target motion parameter estimation methods in the related art have a large amount of computation, resulting in low efficiency.

[0004] In a first aspect, this application provides a method for estimating target motion parameters, comprising: dividing the target echo into multiple sub-aperture echoes; each sub-aperture echo comprising an echo of several consecutive pulses; performing GRFT processing on each sub-aperture echo to obtain the sub-aperture GRFT result corresponding to the sub-aperture echo; fusing all sub-aperture GRFT results into a full-aperture GRFT result, and estimating the motion parameters of the target based on the full-aperture GRFT result.

[0005] In the above implementation process, the target echo is divided into multiple sub-aperture echoes. Each sub-aperture echo undergoes GRFT processing to obtain the corresponding sub-aperture GRFT result. Then, all sub-aperture GRFT results are fused into a full-aperture GRFT result. The target's motion parameters are estimated based on the full-aperture GRFT result. In this way, by using sub-aperture technology to reduce the order of the parameter search space within each sub-aperture and increase the parameter search step size, the computational load of GRFT is reduced. Finally, through sub-aperture fusion, the target motion parameters are estimated, effectively improving estimation efficiency while maintaining estimation accuracy.

[0006] Furthermore, in some examples, the sub-aperture echo includes 16 pulse echoes; the GRFT processing of each sub-aperture echo includes: performing first-order GRFT processing on each sub-aperture echo.

[0007] In the above implementation, a sub-aperture is formed by using the echo of 16 pulses, resulting in a relatively small sub-aperture length. This means that only a first-order GRFT is required for each sub-aperture, thus minimizing the computational load of the GRFT.

[0008] Furthermore, in some examples, the sub-aperture GRFT results are expressed based on the following formula:

[0009]

[0010] in, Indicates the first Sub-aperture GRFT results corresponding to each sub-aperture echo; Indicates the first The constant term of the Taylor expansion of the slant distance history of each aperture. This represents the first-order component coefficients of the slant range history; This indicates the duration of each sub-aperture; Indicates the first The aperture center time of each aperture; Indicates distance to time; Indicates direction and time; The signal expression representing the range-compressed echo signal after transformation to the range frequency domain; Indicates the first Envelope-phase matched filter with individual aperture; Represents the imaginary unit; The speed of light; For carrier frequency; For the frequency domain of the constant term in the Taylor expansion of the slant range history.

[0011] In the above implementation process, an expression for sub-aperture GRFT is provided.

[0012] Furthermore, in some examples, fusing all sub-aperture GRFT results into a full-aperture GRFT result includes: searching for the position of each point in the full-aperture GRFT parameter search space corresponding to the position in each sub-aperture GRFT result; obtaining the energy of the position through interpolation and coherently superimposing them to obtain the full-aperture GRFT result.

[0013] In the above implementation process, a method similar to the fast backward projection algorithm is adopted to find the position of each point in the full aperture GRFT parameter search space corresponding to the position in each sub-aperture GRFT result. Then, the energy at that position is obtained by interpolation and coherently superimposed to complete the sub-aperture GRFT fusion.

[0014] Furthermore, in some examples, fusing all sub-aperture GRFT results into a full-aperture GRFT result includes: correcting the coherent peaks in each sub-aperture GRFT result to the same distance gate; correcting the coherent peaks to the same position along the parameter domain direction of the first expansion term coefficient; and fusing the sub-aperture GRFT results into a full-aperture GRFT result through sub-aperture coherent superposition.

[0015] In the above implementation process, another specific implementation method for sub-aperture GRFT fusion is provided. Compared with interpolation processing, this method can reduce the amount of computation and improve the fusion accuracy.

[0016] Furthermore, in some examples, correcting the coherent peaks in the GRFT results of each sub-aperture to the same range gate includes: performing a Fast Fourier Transform on the GRFT results of each sub-aperture along the range parameter domain and compensating for a first phase; the first phase is expressed based on the following formula:

[0017] in, Indicates the first phase; The total number of sub-aperture GRFT results; Indicates from The number of combinations of selecting one element from a set of elements.

[0018] In the above implementation process, the GRFT results of each sub-aperture are subjected to FFT along the distance parameter domain to transform the signal to the frequency domain. In the distance frequency domain, the signal is compensated for the first phase, thereby accurately aligning the coherence peaks of each sub-aperture to the same distance gate.

[0019] Furthermore, in some examples, correcting the coherent peak to the same position along the parameter domain direction of the first expansion term coefficients includes: performing a Fast Fourier Transform on the GRFT results of each sub-aperture along the parameter domain corresponding to the first expansion term coefficients, and compensating for the second phase; the second phase is expressed based on the following formula:

[0020]

[0021] in, This indicates the second phase.

[0022] In the above implementation process, after compensating for the first phase, The parameter frequency domain and support domain will change; based on this, in The second phase is compensated by domain compensation, thereby accurately correcting the coherence peaks of each sub-aperture to the same position.

[0023] Furthermore, in some examples, the process of fusing the sub-aperture GRFT results into a full-aperture GRFT result through coherent superposition of sub-apertures includes: coherently superimposing each sub-aperture GRFT result into the two-dimensional parametric frequency domain empty matrix of the full-aperture GRFT result; and transforming the full-aperture GRFT result to the target parameter domain by performing an inverse fast Fourier transform along the two-dimensional parametric frequency domain.

[0024] In the above implementation process, the GRFT results of each sub-aperture are coherently superimposed onto the full-aperture GRFT result. In a two-dimensional parametric frequency domain empty matrix, then along Perform IFFT in the two-dimensional parametric frequency domain, and then convert the full-aperture GRFT results to... Two-dimensional parameter frequency domain transformation to The parameter domain is used to complete the sub-aperture GRFT fusion.

[0025] Secondly, this application provides a target motion parameter estimation device, comprising: a partitioning module for partitioning the target echo into multiple sub-aperture echoes; each sub-aperture echo includes an echo of several consecutive pulses; a processing module for performing GRFT processing on each sub-aperture echo to obtain the sub-aperture GRFT result corresponding to the sub-aperture echo; and a fusion module for fusing all sub-aperture GRFT results into a full-aperture GRFT result, and estimating the motion parameters of the target based on the full-aperture GRFT result.

[0026] Thirdly, this application provides an electronic device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the method described in any of the first aspects.

[0027] Fourthly, this application provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the method described in any of the first aspects.

[0028] Fifthly, this application provides a computer program product that, when run on a computer, causes the computer to perform the method described in any of the first aspects.

[0029] Other features and advantages disclosed in this application will be set forth in the following description, or some features and advantages may be inferred from the description or determined without doubt, or may be learned by practicing the above-described technology disclosed in this application.

[0030] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A flowchart illustrating a target motion parameter estimation method provided in this application embodiment; Figure 2 A schematic diagram of sub-aperture GRFT fusion provided in an embodiment of this application; Figure 3 A schematic diagram of the projection of the coherent peaks of the fast GRFT results provided in this application onto a two-dimensional plane, wherein, Figure 3 (a) The coherent peaks of the fast GRFT results are in A projection of a two-dimensional plane. Figure 3 (b) The coherent peaks of the fast GRFT results are in A projection of a two-dimensional plane. Figure 3 (c) The coherent peaks of the fast GRFT results are in A projection of a two-dimensional plane; Figure 4 A block diagram of a target motion parameter estimation device provided in an embodiment of this application; Figure 5 This is a structural block diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0033] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0034] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0035] SAR systems offer advantages such as large imaging range, all-weather operation, and all-time coverage, making them widely used in environmental monitoring, resource exploration, and marine observation. Accurate estimation of target motion parameters is crucial for obtaining high-resolution, high-quality images in SAR imaging. GRFT is a motion parameter estimation method used in radar signal processing. It achieves coherent energy accumulation and motion parameter estimation of the target through global search and matching in a high-dimensional motion parameter space. However, traditional GRFT methods are computationally intensive, resulting in low efficiency in target motion parameter estimation.

[0036] To address the aforementioned issues, this application provides a target motion parameter estimation scheme. The target echo is divided into multiple sub-aperture echoes. Each sub-aperture echo undergoes GRFT processing to obtain its corresponding sub-aperture GRFT result. All sub-aperture GRFT results are then fused into a full-aperture GRFT result. The target's motion parameters are estimated based on this full-aperture GRFT result. In this way, the sub-aperture technique reduces the order of the parameter search space within each sub-aperture and increases the parameter search step size, thereby reducing the computational load of GRFT. Finally, through sub-aperture fusion, the target motion parameters are estimated, effectively improving estimation efficiency while maintaining estimation accuracy.

[0037] The embodiments of this application will be described below: like Figure 1 As shown, Figure 1 This is a flowchart illustrating a target motion parameter estimation method provided in an embodiment of this application. The method includes: Step 101: Divide the target echo into multiple sub-aperture echoes; each sub-aperture echo includes the echo of several consecutive pulses; The target mentioned in this step can refer to targets that need to be detected, identified, and tracked, such as vegetation and animals on the ground, and ships and ice floes on the sea. Taking a moving target on the sea surface as an example, the target's echo can be an electromagnetic signal containing information about the target's geometric and physical characteristics, which is reflected back by various scattering bodies on the sea surface after the electromagnetic wave pulse emitted by the SAR is irradiated, and then captured by the radar receiver. The shorter the echo accumulation time, the larger the search step size for first-order and higher motion parameters, and the order of the parameter search space will also decrease as the echo accumulation time decreases. Based on this, in this embodiment, the target's echo is divided into multiple sub-aperture echoes in the azimuth time domain. This can reduce the order of the parameter search space within the sub-aperture and increase the parameter search step size, thereby reducing the computational load of GRFT.

[0038] Step 102: Perform GRFT processing on each sub-aperture echo to obtain the sub-aperture GRFT result corresponding to the sub-aperture echo; This step refers to: processing each sub-aperture echo using GRFT to obtain the sub-aperture GRFT result corresponding to each sub-aperture echo. The sub-aperture GRFT result can include the motion state information of the target within the sub-aperture, such as the target's distance and velocity relative to the radar.

[0039] In some embodiments, the sub-aperture echo mentioned in this step includes an echo of 16 pulses; accordingly, the GRFT processing of each sub-aperture echo mentioned in this step may include performing a first-order GRFT on each sub-aperture echo. That is, using an echo of 16 pulses as a sub-aperture results in a smaller sub-aperture length. This means that within a single sub-aperture, the second-order and higher-order components in the envelope-phase matched filter are smaller, and these components do not affect the coherent accumulation of the signal during the GRFT process. In this case, the second-order and higher-order components in the envelope-phase matched filter can be ignored, and only a first-order GRFT is needed for each sub-aperture. This minimizes the computational load of the GRFT process.

[0040] Full-aperture GRFT can be expressed as: , among them and These are the motion parameters for the entire aperture. The constant term in the Taylor expansion of the slant distance history is represented by... Represents the first pore size across the entire aperture range. First-order motion parameters, The duration for the entire aperture. This represents the signal expression of the range-compressed echo signal after transformation to the range frequency domain. Indicates distance to time. Indicates direction and time. This represents the full-aperture envelope-phase matched filter. The full-aperture GRFT transform is performed to the range frequency domain, and then Taylor expansion is performed to... At that time, we can obtain:

[0041] Since the sub-aperture echo only requires a first-order GRFT to meet the accuracy requirements. The higher-order components are negligible. Therefore, in some embodiments, the sub-aperture GRFT result mentioned in this step can be expressed based on the following formula:

[0042]

[0043] in, Indicates the first Sub-aperture GRFT results corresponding to each sub-aperture echo; Indicates the first The constant term of the Taylor expansion of the slant distance history of each aperture. This represents the first-order component coefficients of the slant range history; This indicates the duration of each sub-aperture; Indicates the first The aperture center time of each aperture; Indicates the first Envelope-phase matched filter with individual aperture; Represents the imaginary unit; The speed of light; For carrier frequency; This represents the frequency domain of the constant term in the Taylor expansion of the slant range history. Thus, using the above formula, the first-order GRFT results of the echoes from each sub-aperture can be obtained quickly and accurately.

[0044] Step 103: Fuse all sub-aperture GRFT results into a full-aperture GRFT result, and estimate the motion parameters of the target based on the full-aperture GRFT result.

[0045] In this embodiment, the equivalent full-aperture GRFT result is reconstructed using the sub-aperture GRFT results corresponding to the echoes of each sub-aperture, and based on this, a final high-precision estimate of the target motion parameters is obtained. Thus, while ensuring estimation accuracy, estimation efficiency is effectively improved. The motion parameters here may include at least one of the following: spatial position parameters, orientation parameters, velocity parameters, etc.

[0046] In some embodiments, fusing all sub-aperture GRFT results into a full-aperture GRFT result as mentioned in this step may include: searching for the position of each point in the full-aperture GRFT parameter search space corresponding to each sub-aperture GRFT result; obtaining the energy at the position through interpolation and coherently superimposing them to obtain the full-aperture GRFT result. That is, a method similar to the fast backward projection algorithm can be used to find the position of each point in the full-aperture GRFT parameter search space corresponding to each sub-aperture GRFT result, then obtaining the energy at that position through interpolation and coherently superimposing it to complete the sub-aperture fusion.

[0047] In some other embodiments, fusing all sub-aperture GRFT results into a full-aperture GRFT result as mentioned in this step may include: correcting the coherent peaks in each sub-aperture GRFT result to the same range gate; correcting the coherent peaks along the parameter domain direction of the first-order expansion term coefficients to the same position; and fusing the sub-aperture GRFT results into a full-aperture GRFT result through sub-aperture coherent superposition. That is, when fusing the sub-aperture GRFT results, firstly, the coherent peaks in each sub-aperture GRFT result are corrected to the same range gate. Here, the range gate refers to a discrete interval divided by time delay sampling of the radar echo signal, with each interval corresponding to a specific range cell; then, the coherent peaks are corrected along the parameter domain direction of the first-order expansion term coefficients, i.e., The parameter domain orientation is corrected to the same position, thereby shifting the sub-aperture GRFT result into the full-aperture GRFT result. The corresponding positions in the parameter domain are determined; finally, by coherently superimposing the sub-aperture GRFT results, the sub-aperture GRFT results can be fused into a full-aperture GRFT result. Compared to interpolation, this method can reduce the computational load and improve the fusion accuracy.

[0048] Optionally, the aforementioned correction of the coherent peaks in the GRFT results of each sub-aperture to the same range gate may include: performing a Fast Fourier Transform on the GRFT results of each sub-aperture along the range parameter domain and compensating for a first phase; the first phase is represented by the following formula:

[0049] in, Indicates the first phase; The total number of sub-aperture GRFT results; Indicates from The number of combinations in which one element is selected from each element. In other words, the GRFT results of each sub-aperture can be subjected to FFT (Fast Fourier Transform) along the distance parameter domain to transform the signal to the frequency domain. In the distance frequency domain, the signal is compensated for the first phase, thereby accurately aligning the coherence peaks of each sub-aperture to the same distance gate.

[0050] Optionally, the aforementioned correction of the coherent peaks to the same position along the parameter domain direction of the first expansion term coefficients may include: performing a Fast Fourier Transform on the GRFT results of each sub-aperture along the parameter domain corresponding to the first expansion term coefficients, and compensating for the second phase; the second phase is represented by the following formula:

[0051]

[0052] in, This refers to the second phase. That is, since the first phase contains information about... The linear term, therefore, after compensating for this first phase, The parameter frequency domain and support domain will change; therefore, it is necessary to... Domain compensation second phase This allows the coherence peaks of each sub-aperture to be precisely corrected to the same position.

[0053] Furthermore, in some embodiments, the aforementioned method of fusing sub-aperture GRFT results into a full-aperture GRFT result through coherent superposition of sub-apertures may include: coherently superimposing each sub-aperture GRFT result into the two-dimensional parametric frequency domain empty matrix of the full-aperture GRFT result; and transforming the full-aperture GRFT result to the target parameter domain by performing an inverse fast Fourier transform along the two-dimensional parametric frequency domain. Here, the two-dimensional parametric frequency domain is... Two-dimensional parametric frequency domain. That is to say, based on the characteristics of GRFT, in... A two-dimensional parametric frequency domain method is used to achieve sub-aperture GRFT fusion. Specifically, the GRFT results of each sub-aperture are coherently superimposed onto the full-aperture GRFT result. In a two-dimensional parametric frequency domain empty matrix, then along Performing an IFFT (Inverse Fast Fourier Transform) in the frequency domain of two-dimensional parameters, the full-aperture GRFT result is transformed into... Two-dimensional parameter frequency domain transformation to The parameter domain is used to complete the sub-aperture GRFT fusion.

[0054] In this embodiment, the target echo is divided into multiple sub-aperture echoes. Each sub-aperture echo undergoes GRFT processing to obtain its corresponding sub-aperture GRFT result. All sub-aperture GRFT results are then fused into a full-aperture GRFT result. The target's motion parameters are estimated based on this full-aperture GRFT result. Thus, by using sub-aperture technology to reduce the order of the parameter search space within each sub-aperture and increase the parameter search step size, the computational load of GRFT is reduced. Finally, through sub-aperture fusion, the target motion parameters are estimated, effectively improving estimation efficiency while maintaining estimation accuracy.

[0055] To provide a more detailed explanation of the solution in this application, a specific embodiment is described below: This embodiment provides a target motion parameter estimation scheme based on the fast GRFT method. The core idea of ​​the fast GRFT method is to reduce the order of the parameter search space within the sub-aperture and increase the parameter search step size by using sub-aperture technology, thereby reducing the computational complexity of sub-aperture GRFT. Finally, sub-aperture fusion is completed in the range-velocity two-dimensional frequency domain, achieving efficient motion parameter estimation.

[0056] The fast GRFT method provided by this scheme includes the following steps: S201. Target echo sub-aperture division; specifically, the target echo is divided in the azimuth and time domain into... In implementation, each sub-aperture echo uses 16 pulses of echo as a sub-aperture echo, making the order of each sub-aperture GRFT 1. S202. Perform a first-order GRFT on the sub-aperture echo; specifically, the expression for the first-order GRFT of the sub-aperture is as follows:

[0057] In equation (1), Indicates the first The expression for a sub-aperture envelope-phase matched filter is:

[0058] In equation (2), and It is the first Motion parameters of individual apertures; S203. Fuse the GRFT results of the echoes from each sub-aperture; Specifically, sub-aperture GRFT fusion involves finding the energy at each point within the full-aperture GRFT parameter search space that corresponds to the energy in each sub-aperture GRFT result, and then coherently superimposing them. For example... Figure 2 As shown, in the full aperture GRFT result, block 21 represents the energy obtained by coherently superimposing the target range migration curve 22 (shown as a dashed line in the figure) in the echo. At this time, the target range migration curve 22 matches the scattering point range migration curve 23 (shown as a solid line in the figure), and a coherent peak will appear in the full aperture GRFT result. If the echo is divided into four sub-aperture echoes, the target range migration curve 22 will also be divided into four sub-range migration curves (numbered 24, 25, 26, and 27 in the figure). The four blocks corresponding to the sub-aperture GRFT result (numbered 28, 29, 30, and 31 in the figure) will also each have a coherent peak. Therefore, sub-aperture fusion is to coherently superimpose these four coherent peaks and place the superimposed energy at block 21 in the full aperture GRFT result. At this time, the four coherent peaks in the sub-aperture GRFT result are superimposed to form a new coherent peak in the full aperture GRFT result. This embodiment of the solution is based on the characteristics of GRFT and employs a method in... A method for sub-aperture GRFT fusion in the two-dimensional parametric frequency domain includes the following steps: S2031. Since the order of the full aperture GRFT is greater than 1, when fusing sub-aperture GRFTs, the row order of the sub-aperture GRFT is first expanded. For example, an empty matrix of a sub-aperture high-order GRFT is constructed, and the sub-aperture GRFT is copied and stored in the empty matrix. S2032. Perform FFT on the sub-aperture GRFT result along the distance parameter domain, and compensate for the phase as shown in the following formula:

[0059] This step corrects the coherent peaks in the GRFT results of each sub-aperture to the same distance gate. S2033, The sub-aperture GRFT result is along... Perform FFT in the parameter domain and compensate for the phase as shown in equation (4):

[0060]

[0061] This step involves adjusting the coherent peaks in the GRFT results of each sub-aperture along... The parameter domain orientation is corrected to the same position; S2034. According to equation (5), coherently superimpose the GRFT results of each sub-aperture to the full-aperture GRFT result. In a two-dimensional parametric frequency domain empty matrix, then along Perform IFFT in the two-dimensional parametric frequency domain, and then convert the full-aperture GRFT results to... Two-dimensional parameter frequency domain transformation to The parameter domain is used to complete the sub-aperture GRFT fusion.

[0062] To verify the effectiveness of the aforementioned fast GRFT method, a point target simulation experiment was conducted. During implementation, the slant range history of the simulated point target was recorded. for:

[0063] Motion parameter estimation is performed based on the Fast GRFT method. The Fast GRFT parameters are shown in Table 1. It should be noted that, to verify the accuracy of the Fast GRFT method, the search step size for the motion parameters is set to be relatively small. However, in practical applications, the search step size only needs to meet the following requirements. , and The conditions shown are sufficient. Table 1 contains the following information: Table 1. Fast GRFT parameters in point target simulation data processing

[0064] The projection of the coherent peaks of the fast GRFT result onto the two-dimensional plane is as follows: Figure 3 As shown, where, Figure 3 (a) The coherent peaks of the fast GRFT results are in A projection of a two-dimensional plane. Figure 3 (b) The coherent peaks of the fast GRFT results are in A projection of a two-dimensional plane. Figure 3 (c) The coherent peaks of the fast GRFT results are in The projection diagram on the two-dimensional plane. When the motion parameters of the envelope-phase matched filter are consistent with the actual values, a coherent peak will appear in the diagram. Based on the position of this coherent peak, the estimated motion parameters of the point target simulation can be obtained as shown in Table 2. The estimated motion parameters of each order in Table 2 are consistent with the simulation settings, verifying the effectiveness of the fast GRFT method. The contents of Table 2 are as follows: Table 2. Motion parameter estimation results of point target simulation based on fast GRFT

[0065] To further verify the effectiveness of the fast GRFT method in this embodiment, the fast GRFT results were compared with the traditional GRFT results. The comparison results showed that the coherence peaks of the fast GRFT and traditional GRFT results were basically consistent in each dimension profile. Therefore, it can be seen that the fast GRFT method is comparable to the traditional GRFT method in terms of accuracy.

[0066] In addition, to verify the efficiency of the proposed algorithm, the computational cost of the fast GRFT method and the traditional GRFT method was compared. The computational cost of the traditional GRFT method was 8.80 TFLOPs, while the computational cost of the fast GRFT method was 0.12 TFLOPs, which is 98.64% lower than that of the traditional GRFT method, nearly two orders of magnitude.

[0067] In summary, the fast GRFT method used in this embodiment can effectively reduce the amount of computation while maintaining the same accuracy as the traditional GRFT method. Therefore, it can improve the estimation efficiency when estimating target motion parameters based on fast GRFT.

[0068] Corresponding to the embodiments of the aforementioned methods, this application also provides embodiments of a target motion parameter estimation device and a terminal for its application: like Figure 4 As shown, Figure 4 This is a block diagram of a target motion parameter estimation device provided in an embodiment of this application. The device includes: The segmentation module 41 is used to divide the target's echo into multiple sub-aperture echoes; each sub-aperture echo includes the echo of several consecutive pulses. Processing module 42 is used to perform GRFT processing on each sub-aperture echo to obtain the sub-aperture GRFT result corresponding to the sub-aperture echo; The fusion module 43 is used to fuse all sub-aperture GRFT results into a full-aperture GRFT result, and to estimate the motion parameters of the target based on the full-aperture GRFT result.

[0069] The specific implementation process of the functions and roles of each module in the above device can be found in the implementation process of the corresponding steps in the above method, and will not be repeated here.

[0070] This application also provides an electronic device, please refer to [link to application]. Figure 5 , Figure 5 This is a structural block diagram of an electronic device provided in an embodiment of this application. The electronic device may include a processor 510, a communication interface 520, a memory 530, and at least one communication bus 540. The communication bus 540 is used to enable direct communication between these components. In this embodiment, the communication interface 520 of the electronic device is used for signaling or data communication with other node devices. The processor 510 may be an integrated circuit chip with signal processing capabilities.

[0071] The processor 510 described above can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can be a microprocessor, or the processor 510 can be any conventional processor.

[0072] The memory 530 may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc. The memory 530 stores computer-readable instructions. When these computer-readable instructions are executed by the processor 510, the electronic device can perform the aforementioned operations. Figure 1 The various steps involved in the method implementation examples.

[0073] Alternatively, the electronic device may also include a storage controller and an input / output unit.

[0074] The memory 530, storage controller, processor 510, peripheral interface, and input / output unit are electrically connected directly or indirectly to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses 540. The processor 510 is used to execute executable modules stored in the memory 530, such as software function modules or computer programs included in electronic devices.

[0075] The input / output unit is used to provide users with the ability to create tasks and to set optional start periods or preset execution times for those tasks, thereby enabling user-server interaction. The input / output unit may be, but is not limited to, a mouse and keyboard.

[0076] Understandable. Figure 5 The structure shown is for illustrative purposes only; the electronic device may also include components that are more advanced than those shown. Figure 5 The more or fewer components shown, or having the same Figure 5 The different configurations shown. Figure 5 The components shown can be implemented using hardware, software, or a combination thereof.

[0077] This application also provides a storage medium storing instructions. When the instructions are run on a computer, the computer program is executed by a processor to implement the method described in the method embodiment. To avoid repetition, the method will not be described again here.

[0078] This application also provides a computer program product that, when run on a computer, causes the computer to perform the method described in the method embodiment.

[0079] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0080] In addition, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0081] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0082] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0083] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0084] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, 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. Without further limitations, 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 said element.

Claims

1. A method for estimating target motion parameters, characterized in that, include: The target's echo is divided into multiple sub-aperture echoes; each sub-aperture echo consists of several consecutive pulses of echo. Perform GRFT processing on the echoes of each sub-aperture to obtain the GRFT results of the sub-aperture echoes; All sub-aperture GRFT results are fused into a full-aperture GRFT result, and the motion parameters of the target are estimated based on the full-aperture GRFT result. The sub-aperture echo comprises 16 pulses of echo; The GRFT processing of the echoes from each sub-aperture includes: Perform first-order GRFT processing on the echoes of each sub-aperture; The process of fusing all sub-aperture GRFT results into a full-aperture GRFT result includes: Correct the coherent peaks in the GRFT results of each sub-aperture to the same distance gate; The coherent peaks are corrected to the same position along the parameter domain direction of the first expansion term coefficients; Sub-aperture GRFT results are fused into full-aperture GRFT results by coherent superposition of sub-apertures; The step of correcting the coherent peaks in the GRFT results of each sub-aperture to the same distance gate includes: The GRFT results of each sub-aperture are subjected to Fast Fourier Transform along the distance parameter domain, and the first phase is compensated.

2. The method according to claim 1, characterized in that, The sub-aperture GRFT results are expressed based on the following formula: in, Indicates the first Sub-aperture GRFT results corresponding to each sub-aperture echo; Indicates the first The constant term of the Taylor expansion of the slant distance history of each aperture. This represents the first-order component coefficient of the slant range history; This indicates the duration of each sub-aperture; Indicates the first The aperture center time of each aperture; Indicates distance to time; Indicates direction and time; The signal expression representing the range-compressed echo signal after transformation to the range frequency domain; Indicates the first Envelope-phase matched filter with individual aperture; Represents the imaginary unit; The speed of light; For carrier frequency; For the frequency domain of the constant term in the Taylor expansion of the slant range history.

3. The method according to claim 1, characterized in that, The process of fusing all sub-aperture GRFT results into a full-aperture GRFT result includes: Search the full aperture GRFT parameters search space to find the position of each point in the sub-aperture GRFT results; The energy at the specified location is obtained through interpolation and coherently superimposed to obtain the full-aperture GRFT result.

4. The method according to claim 2, characterized in that, The first phase is represented by the following formula: in, Indicates the first phase; The first one in the full aperture range First-order motion parameters; The total number of sub-aperture GRFT results; Indicates from The number of combinations of selecting one element from a set of elements.

5. The method according to claim 4, characterized in that, The step of correcting the coherent peak to the same position along the parameter domain direction of the first expansion term coefficient includes: The GRFT results of each sub-aperture are subjected to Fast Fourier Transform along the parameter domain corresponding to the coefficients of the first expansion term, and the second phase is compensated. The second phase is represented by the following formula: in, This indicates the second phase.

6. The method according to claim 4, characterized in that, The process of fusing sub-aperture GRFT results into a full-aperture GRFT result through coherent superposition of sub-apertures includes: The GRFT results of each sub-aperture are coherently superimposed into the two-dimensional parametric frequency domain spatial matrix of the full-aperture GRFT result; The full-aperture GRFT result is transformed to the target parameter domain by performing an inverse fast Fourier transform along the two-dimensional parameter frequency domain.

7. A target motion parameter estimation device, characterized in that, The apparatus is used to implement the method as described in any one of claims 1 to 6; the apparatus comprises: The segmentation module is used to divide the target's echo into multiple sub-aperture echoes; each sub-aperture echo consists of several consecutive pulses of echo. The processing module is used to perform GRFT processing on each sub-aperture echo to obtain the sub-aperture GRFT result corresponding to the sub-aperture echo. The fusion module is used to fuse all sub-aperture GRFT results into a full-aperture GRFT result, and to estimate the motion parameters of the target based on the full-aperture GRFT result.

8. A computer-readable storage medium, characterized in that, It stores a computer program thereon, which, when executed by a processor, implements the method as described in any one of claims 1 to 6.

9. An electronic device, characterized in that, It includes a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method as claimed in any one of claims 1 to 6.

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