Radar sea clutter coherent echo generation method based on microcosmic fluid mechanics evolution

Abstract

The application discloses a radar sea clutter coherent echo generation method based on microcosmic fluid mechanics evolution. In view of the problems that the PM spectrum lacks high-frequency capillary waves in traditional sea surface modeling, the Bragg scattering energy of the microwave band is seriously underestimated, and the empirical statistical model deviates from the actual ocean dynamics, a physical driving full-link simulation framework is provided. Specifically, the nonlinear sea surface is reconstructed by combining the Elfouhaily full spectrum and the Creamer theory; the polarization scattering is calculated by using a two-scale model which introduces large-scale curvature compensation and small-scale non-Gaussian slope correction; the sea surface particle dynamics parameters and K distribution shape parameters are strictly solved from each order spectrum moment of the two-dimensional sea wave direction spectrum; and finally, the physically coupled coherent echo is synthesized. The clutter sequence generated by the application effectively overcomes the extreme 'clutter spike' distortion of the single gravity wave model, and significantly improves the confidence of radar detection evaluation under complex sea conditions.

Description

Technical Field

[0001] This invention relates to the fields of computational electromagnetics and radar environment simulation technology, specifically to a radar sea clutter coherent echo generation method based on microhydrodynamic evolution, which is applicable to engineering applications such as high-fidelity sea clutter time-domain sequence generation under complex sea conditions, radar constant false alarm rate (CFAR) detection algorithm optimization, and anti-sea clutter performance evaluation. Background Technology

[0002] With the widespread application of modern high-resolution, low-scratch radar in maritime detection and electronic warfare, high-fidelity modeling of background clutter in complex marine environments has become a critical technology that urgently needs to be solved. The dramatic evolution of sea surface winds and waves not only causes multipath interference and specular reflection of electromagnetic waves, but its micro-hydrodynamic evolution also triggers a dramatic broadening of the clutter spectrum and a non-Gaussian "heavy tail" effect in amplitude distribution.

[0003] Existing methods for predicting and simulating sea clutter face multiple technical bottlenecks when dealing with complex sea states. At the level of sea surface geometry modeling, traditional physics-driven models largely rely on the Pierson-Moskowitz (PM) narrowband gravity spectrum, severely lacking high-frequency capillary wave components; in the microwave radar band, this leads to a significant underestimation of the Bragg resonance energy, which dominates electromagnetic backscattering. At the level of electromagnetic scattering calculation, traditional two-scale models are based on a simple Gaussian slope assumption and do not consider the curvature effect of large-scale surface elements, resulting in a significant increase in calculation errors at maximum incident angles of 70°–85°. At the level of clutter temporal generation, the shape parameters and Doppler parameters of the traditional K-distribution largely rely on the splicing of semi-empirical constants, failing to achieve strict coupling of bottom-level ocean dynamic physical parameters, ultimately causing the generated synthetic echoes to deviate from true physical laws in terms of amplitude fluctuations and Doppler broadening.

[0004] In existing technologies, simple amplitude distribution fitting fails to address the lack of physical mechanisms; radar cross-section (RCS) calculation schemes based on empirical constants lead to unstable model accuracy under different radar azimuth angles; and the combination of traditional linear wave modeling and simple probability distribution methods lacks fidelity in dynamic scenarios. A more fundamental deficiency lies in the lack of an adaptive mechanism for ocean microscale hydrodynamics, making it impossible to maintain stable physical feature reproduction under multiple constraints such as extreme incident angles, strong wind speeds, and wave nonlinear modulation. Summary of the Invention

[0005] This invention provides a method and system for generating coherent radar clutter echoes based on microfluidic evolution. Addressing the shortcomings of existing technologies, such as the lack of high-frequency capillary waves, extremely low scattering distortion at the ground grazing angle, and empirical reliance on statistical parameters, this invention constructs a hybrid computational framework integrating the Elfouhaily full-spectrum spatial index, modified polarization dual-scale theory, and physical spectral moment parameter derivation, thereby achieving efficient and accurate solutions for high-fidelity clutter signals.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for generating coherent radar sea surface clutter echoes based on microfluidic evolution includes the following steps:

[0008] S100, Microhydrodynamic Sea Surface Numerical Discretization and Nonlinear Reconstruction. Marine environmental parameters are acquired, and combined with the Elfouhaily full spectrum containing complete gravity-capillary wave components and Creamer nonlinear theory, a high-resolution three-dimensional dynamic sea surface is generated.

[0009] Specifically, the Elfouhaily full-band space wavenumber spectrum is calculated, which is divided into low-frequency gravity waves. Calculation and high frequency capillary wave : ;in, Indicates wavenumber. The Elfouhaily full spectrum fully covers the entire frequency range from long gravity waves to short capillary waves, effectively making up for the lack of high-frequency components in the traditional PM spectrum.

[0010] To address the nonlinear effects of actual ocean waves, a Creamer perturbation term is introduced based on the linear sea surface frequency domain height field. A Taylor expansion of the exponential term is performed, retaining the second-order approximation, to obtain its nonlinear compensation matrix. Represented as:

[0011] In the formula, , These are represented as the components of the two-dimensional spatial wavenumber vector in the x-axis and y-axis directions, respectively; This represents the Fourier transform, a process that eliminates the linear illusion of symmetrical peaks and troughs, reconstructing a true fluid world with sharp peaks and gentle troughs. This represents the wavefront height.

[0012] S200, Polarimetric Spatial Scattering Calculation Based on Modified Two-Scale Model (Modified TSM). A wavenumber truncation threshold is set, dividing the reconstructed sea surface into large-scale basal elements and small-scale perturbation ripples. For each grid cell, its backscattering coefficient is calculated:

[0013]

[0014] in, Angle of incidence The scattering angle is... , These represent the local incident angle and scattering angle, respectively. This represents the backfield scattering coefficient calculated using the KA method. This represents the back-field scattering coefficient calculated by the IEM method. and These represent the polarization modes of the scattered field and the incident field (horizontal polarization H or vertical polarization V), respectively.

[0015] To address the curvature effect under large incident angle conditions, Kirchhoff's approximation (KA) is adopted, and a first-order 1 / 3 Hankel function is introduced. Calculate the polarization curvature correction factor and To compensate for the diffraction effect of electromagnetic waves at the edge of wave crests:

[0016] ;

[0017] in, Let the wave number be the incident electromagnetic wave. Where is the dielectric constant of air. Let be the local radius of curvature of a large-scale surface element on the sea surface.

[0018] For small-scale incoherent scattering (SPM), the standard Gaussian distribution assumption is abandoned, and a skewness-inclusive distribution is introduced. ) and kurtosis ( ) is expanded into a series to calculate the corrected joint probability density function of sea surface slope. Simultaneously, a multipath shielding attenuation factor at extremely low grazing angles is introduced into the perturbation term. .

[0019] S300, physical-driven dynamic solution of composite Gaussian statistical parameters. It abandons the use of semi-empirical constants to set the shape parameters of the K-distribution in clutter simulation. The traditional approach. Based on the evolution of the underlying wave spectrum, the modulation depth of short waves is dynamically derived through large-scale waves. :

[0020] Calculate the number of effective independent Bragg scatterers within the radar illumination area. ; Extract the slope variance of large-scale waves from the spatial grid, and rigorously calculate three micro-scale modulation mechanisms:

[0021] Tilt modulation Based on the coupling of mean square slope and incident angle tangent;

[0022] Fluid dynamics modulation The energy of short waves is enhanced at the long wave crest, based on the ratio of Bragg wavenumber to peak wavenumber;

[0023] Area modulation : Dynamic projection changes of the effective irradiated area.

[0024] The dynamic model representation of the shape parameter υ is as follows:

[0025] .

[0026] S400, Doppler dynamics analysis based on two-dimensional wave spectral moments. Based on hydrodynamic dispersion relations. For two-dimensional directional spectra Perform integrations of various orders:

[0027] ;

[0028] Extracting spectral moments from the zeroth to the fourth order to analyze the root mean square orbital velocities of sea surface particles. Mean angular frequency and nonlinear spectral width parameter .

[0029] Integrating ocean dynamics and radar geometric observations, the integrated Doppler broadening is calculated. :

[0030] ;

[0031] In the formula, The intrinsic Doppler broadening caused by long-wave orbital motion; The broadening caused by the combined antenna beamwidth during radar platform movement; To broaden the nonlinear velocity at sea surface, which is strongly correlated with the spectral width parameter; This refers to microscale velocity dispersion caused by local wind field disturbances.

[0032] Verification of S500 and sea surface coherent echo timing synthesis and physical characteristics evaluation. Calculation of fundamental echo power based on radar meteorological equations. Extract the slow-time, large-scale texture undulations generated in the preceding steps. Local polarization RCS distribution of continuous spatial slices and fast-time Gaussian speckle with physical spectral breadth characteristics. A hierarchical fusion of physical coupling is performed to generate complex baseband echoes. :

[0033]

[0034] In the formula, The base echo power is given by τ, where τ represents the slow-time large-scale texture undulations. It is a locally polarized RCS distribution. It is a fast-time Gaussian speckle pattern with a broad physical spectrum. The center frequency of the Doppler wave. To broaden the overall Doppler effect, For radar wavelength, This represents the displacement of a point mass on the sea surface.

[0035] This invention also provides a radar sea surface clutter coherent echo generation system based on microhydrodynamic evolution, comprising:

[0036] The sea surface geometry modeling module is used to reconstruct a three-dimensional dynamic sea surface using Elfouhaily full spectrum and Creamer nonlinear theory.

[0037] The polarization scattering calculation module is used to calculate the polarization backscattering coefficients based on a two-scale model that includes large-scale curvature correction and non-Gaussian slope correction.

[0038] The statistical parameter calculation module is used to dynamically derive the statistical shape parameters of the composite Gaussian distribution based on the bottom-level evolution of the wave spectrum.

[0039] The Doppler dynamics analytical module is used to perform spectral moment integration of various orders on the two-dimensional wave direction spectrum and calculate the comprehensive Doppler broadening.

[0040] The coherent echo synthesis module is used to physically couple and fuse slow-time large-scale texture undulations, local polarization RCS distribution, and fast-time Gaussian speckle to generate coherent echoes.

[0041] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the above method.

[0042] The present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method.

[0043] The beneficial effects of this invention are as follows: The Elfouhaily full-spectrum, by precisely introducing microscale capillary wave perturbations (with a cutoff wavenumber reaching 363 rad / m), makes the scattering background within the radar resolution cell dense and continuous, effectively smoothing the extreme modulation effects caused by large-scale waves, and fundamentally suppressing the extreme "clutter spikes" that do not conform to physical laws caused by the PM gravity wave model. By introducing large-scale curvature correction and non-Gaussian slope joint probability density, the calculation accuracy of the polarization backscattering coefficient across the entire incident angle range is significantly improved. Simultaneously, it achieves a rigorous physical mapping from the underlying physical state of ocean waves to the characteristics of radar echoes, with shape parameters reverting to theoretical values ​​that better reflect real sea conditions, and the asymmetric broadening of the Doppler spectrum highly consistent with actual ocean echo measurement data. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the radar sea clutter coherent echo generation method based on microfluidic evolution according to the present invention.

[0045] Figure 2This is a schematic diagram of the nonlinear three-dimensional sea surface height field constructed by combining the Elfouhaily full spectrum and Creamer theory in this invention;

[0046] Figure 3 This is a schematic diagram of the attenuation curve of the polarization backscattering coefficient with the incident angle calculated using the improved dual-scale model of this invention;

[0047] Among them, (a) is the curve of the backscattering coefficient decreasing with the incident angle calculated by the HH polarization method, and (b) is the curve of the backscattering coefficient decreasing with the incident angle calculated by the VV polarization method.

[0048] Figure 4 This is a schematic diagram comparing the statistical probability density function of the physical drive clutter amplitude generated by the method of this invention with the theoretical K distribution;

[0049] Figure 5 This is a schematic diagram of the frequency power spectrum of the sea surface echo signal generated by the present invention based on the PM spectrum and the Elfouhaily full spectrum. Detailed Implementation

[0050] To better understand the technical solution of this invention, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments. The core of this invention lies in utilizing microscale hydrodynamic evolution laws to replace simple statistical fitting, establishing a rigorous mapping pipeline from the physical state of the seabed to the final radar echo.

[0051] Example

[0052] A radar sea surface clutter coherent echo generation method based on microfluidic evolution, referring to Figure 1 The method includes the following steps:

[0053] Step S100: Numerical Discretization of the Sea Surface in Microhydrodynamics. This step is fundamental to the entire method, and its key lies in completing the mesh generation of the target surface and extracting the geometric parameters of the surface patches. The discretization accuracy directly affects the accuracy of subsequent electromagnetic scattering calculations. In specific implementation, the sea surface mesh size is set to... Spatial sampling rate Setting radar environmental parameters: wind speed at 19.5 meters above sea level. Angle between wind direction and observation direction .

[0054] The algorithm abandons the narrowband gravity wave spectrum of PM that lacks high-frequency characteristics in traditional simulations, and instead adopts the Elfouhaily full wavenumber domain spectrum. The equivalent wind speed at 10 meters is calculated using a formula. Calculate the drag coefficient Frictional wind speed Calculate the peak wavenumber of low-frequency gravity waves. High-frequency capillary cutoff wavenumber By fusing frequency domain filtering with the Creamer second-order Taylor expansion, the height perturbation at grid points caused by nonlinear wave interactions is calculated. The standard deviation is then generated via a two-dimensional inverse fast Fourier transform (IFFT2). Approximately equal to the theoretical value ( A high-fidelity nonlinear sea surface spatial slice (one-quarter of the total). A nonlinear three-dimensional sea surface height field constructed by combining the Elfouhaily full spectrum and Creamer theory is shown below. Figure 2 As shown.

[0055] Step S200: Corrected polarization dual-scale scattering calculation. The core task of this step is to construct an efficient spatial indexing structure, reducing the complexity of intersection testing between rays and patches from O(N) to O(log N), which is a key technical step in realizing fast RCS calculation for electrically large targets.

[0056] In practice, the radar operating frequency is set. Calculate the free space wavenumber and the complex permittivity of seawater (Comprehensive temperature) With salinity ). The cutoff wavenumber for dissecting large / small scale waves. At this point, calculate the large-scale mean square slope. and Iterate through all polarization incident angles (0.5° to 85°), and for low ground-scratching angles greater than 70°, extract the local radius of curvature of the mesh. , utilizing the first type order and Polarization compensation formula for the first-order Hankel function, and calculation of the correction factor. and For Bragg resonances generated by minute ripples, a two-dimensional omnidirectional spectrum expansion was used, embedding elements including wind direction deviation. Non-Gaussian slope joint probability density Perform two-dimensional numerical integration. For example... Figure 3 As shown, compared to the PM spectrum without capillary waves, the modified TSM algorithm based on the Elfouhaily spectrum exhibits a more dramatic but more realistic polarization energy decay at maximum incident angles.

[0057] Step S300: Dynamic solution of physical-driven composite statistical parameters, such as... Figure 4 As shown. This step aims to eliminate the need for manually specifying the shape parameters of the K-distribution in traditional sea clutter modeling. To overcome the limitations, adaptive parameter calculation is achieved by extracting the physical modulation depth of the sea surface grid. The specific process is as follows:

[0058] Gridded modulation depth extraction: For the range-azimuth grid cells divided in S200, based on large-scale sea surface mean square slope (MSS) data provided by Elfouhaily full spectrum, the triple modulation effect caused by microhydrodynamic evolution within the cell is calculated in real time.

[0059] Tilt Modulation: Based on the Slope Variance of Large-Scale Waves Local incident angle of radar Calculate the tilt modulation depth using the tangent value. This section describes how long-wavelength slope affects the incident geometry of local small-scale scatterers.

[0060] Fluid dynamics modulation: based on Bragg wavenumber With peak wavenumber of the sea spectrum The ratio of the two values ​​is used to calculate the hydrodynamic modulation depth. A computational model is adopted. This characterizes the physical convergence effect of long-wave peaks on high-frequency capillary wave energy.

[0061] Area modulation: At low grazing angles, considering the change in the effective scattering area projection caused by wave undulations, the area modulation depth is calculated. .

[0062] Number of independent scatterers ( Deduction: Based on the area of ​​the radar illumination unit Effective correlation length with sea surface determined by peak wavenumber of the sea spectrum Number of independent Bragg scatterers within the solution cell .

[0063] Shape parameters Physical closed-loop solution: Combining the above physical modulation depth Combined with multipath shielding attenuation factor at extremely low grazing angles Derive shape parameters This method ensures that the amplitude non-Gaussian properties of clutter (such as the degree of tailing) are entirely driven by the real-time physical state of the waves.

[0064] Step S400: Analysis of Doppler dynamic characteristics based on wave spectral distance. This step involves analyzing the spectral moments of the wave spectrum to replace traditional empirical constants and constructing a Doppler power spectrum model that reflects the actual physical evolution. The specific implementation process is as follows:

[0065] Calculation of higher-order wave spectrum moment integrals: directly utilizing the generated two-dimensional wave direction spectrum Combining the gravity-capillary wave dispersion relationship Calculate the spectral moments from the zeroth to the fourth order. .

[0066] Microscopic dynamic parameters extraction of particles: Based on statistical theory, the root mean square orbital velocity of sea surface particles is analyzed from the spectral moments. Mean angular frequency And the spectral width parameter reflecting the nonlinear characteristics of sea waves. .

[0067] Vector synthesis of Doppler center and broadening: First, combining the Bragg wave phase velocity with the drift velocity of the local wind-driven ocean current. (Usually taken as 3% of wind speed), Synthetic Doppler Center Secondly, through vector superposition of the physical broadening components at four levels, namely the eigenorbit broadening directly derived from the spectral moments. Radar platform motion extension From the spectral width parameter Determined nonlinear velocity broadening at sea surface and microscale dispersion caused by local wind field disturbances .

[0068] This step effectively solves the problem of narrow Doppler broadening in traditional models by capturing the Doppler contribution of high-frequency capillary waves in the Elfouhaily spectrum, thus improving the physical realism of the echo spectrum.

[0069] Step S500: Coherent echo synthesis and comparison analysis. Based on the above physical parameters, the complex baseband time series received by the radar is synthesized. Comparative tests show that:

[0070] In practical implementation, echoes generated using PM gravity spectrum lack centimeter-scale micro-perturbations (capillary waves), resulting in an inability to provide sustained Bragg resonance within the radar illumination unit. Energy is excessively concentrated in the specular reflection of a few peaks, leading to an extreme heavy tail in the amplitude distribution, i.e., numerous distorted "clutter spikes." In contrast, the echoes generated by this invention using the Elfouhaily full spectrum combined with a microfluidic evolution model effectively fill the scattering gaps with abundant high-frequency physical perturbations, smoothing out large-scale extreme modulations, such as... Figure 5 As shown. Extracting its statistical parameters indicates The value returns to around 3.0, which is more consistent with the actual sea conditions, and the asymmetric broadening of the Doppler spectrum is highly consistent with the actual measured data of ocean echoes.

[0071] Ultimately, the simulation system constructed in this invention not only achieves a low-level physical closed loop for parameters, but also provides a highly confident digital test benchmark for the electromagnetic characteristic analysis of complex sea surface composite targets.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A radar sea surface clutter coherent echo generation method based on microfluidic evolution, characterized in that, Includes the following steps: Step S100: Obtain marine environmental parameters and reconstruct the three-dimensional dynamic sea surface using Elfouhaily full spectrum and Creamer nonlinear theory; Step S200: Set the wavenumber cutoff threshold and calculate the polarization backscattering coefficient based on a dual-scale model that includes large-scale curvature correction and non-Gaussian slope correction; Step S300: Based on the bottom-level evolution of the wave spectrum, the statistical shape parameters of the composite Gaussian distribution are dynamically derived by solving the modulation depth of large-scale waves on short waves. Step S400: Integrate the spectral moments of each order on the two-dimensional wave direction spectrum, extract the mean, root mean square and nonlinear spectral width parameters of the orbital velocity of sea surface particles, analyze the Doppler dynamic characteristics and calculate the comprehensive Doppler broadening; Step S500: Physically couple and fuse the slow-time large-scale texture undulations, local polarization RCS distribution, and fast-time Gaussian speckle with physical spectral width characteristics extracted in the previous steps to synthesize coherent echoes.

2. The method according to claim 1, characterized in that, Step S100 specifically includes: calculating the Elfouhaily full-band spatial wavenumber spectrum, which is divided into low-frequency gravity waves. B l and high-frequency capillary waves B h : ； in, Indicates wave number; Based on the frequency domain height field of a linear sea surface, a Creamer perturbation term is introduced. A Taylor expansion of the exponential term is performed, retaining the second-order approximation. Its nonlinear compensation matrix... Represented as: in, , These are represented as the components of the two-dimensional spatial wavenumber vector along the x-axis and y-axis, respectively. Indicates Fourier transform, This represents the wavefront height.

3. The method according to claim 1, characterized in that, Step S200, which calculates the polarization backscattering coefficient based on a dual-scale model including large-scale curvature correction and non-Gaussian slope correction, specifically includes: for each grid cell, the backscattering coefficient is expressed as: ； in, Angle of incidence The scattering angle is... , These represent the local incident angle and scattering angle, respectively. This represents the backfield scattering coefficient calculated using the KA method. This represents the back-field scattering coefficient calculated by the IEM method. and H represents the horizontal polarization of the scattered field and V represents the vertical polarization of the incident field, respectively. For large-scale surface elements, Kirchhoff approximation is adopted and a Hankel function of the first kind (1 / 3 order) is introduced. Calculated polarization curvature correction factor and To compensate for the diffraction effect of electromagnetic waves at the edge of the wave crest, wherein, ； in, Let the wave number be the incident electromagnetic wave. Where is the dielectric constant of air. The local radius of curvature of a large-scale surface element of the sea surface; For small-scale micro-perturbation ripples, a skewness-inclusive (SDI) component is introduced. ) and kurtosis ( The series expansion of the corrected joint probability density function of sea surface slope. And introduce a multipath shielding attenuation factor at extremely low grazing angles. .

4. The method according to claim 1, characterized in that, The step S300 of dynamically deriving the statistical shape parameters of the composite Gaussian distribution specifically includes: calculating the number of effective independent Bragg scatterers within the radar illumination surface. Extract the slope variance of large-scale waves from the spatial grid, and calculate the tilt modulation depth respectively. Fluid dynamics modulation depth and area modulation depth ; The dynamic model representation of the shape parameter υ is as follows: ； in, This is a low friction angle correction factor.

5. The method according to claim 1, characterized in that, The step S400 of performing spectral moment integrals of various orders on the two-dimensional wave direction spectrum specifically includes: based on the hydrodynamic dispersion relation... For two-dimensional directional spectra Perform integrations of various orders: ； Extracting spectral moments from the zeroth to the fourth order, and analyzing the root mean square orbital velocities of sea surface particles. Mean angular frequency and nonlinear spectral width parameter ; Integrating ocean dynamics and radar geometric observations, the integrated Doppler broadening is calculated. : ； In the formula, The intrinsic Doppler broadening caused by long-wave orbital motion; The broadening caused by the combined antenna beamwidth during radar platform movement; To broaden the nonlinear velocity at sea surface, which is strongly correlated with the spectral width parameter; This refers to microscale velocity dispersion caused by local wind field disturbances.

6. The method according to claim 1, characterized in that, The complex baseband echo X(t) generated in step S500 is specifically represented as follows: In the formula, The base echo power is given by τ, where τ represents the slow-time large-scale texture undulations. It is a locally polarized RCS distribution. It is a fast-time Gaussian speckle pattern with a broad physical spectrum. The center frequency of the Doppler wave. To broaden the overall Doppler effect, For radar wavelength, This represents the displacement of a point mass on the sea surface.

7. A radar sea surface clutter coherent echo generation system based on microfluidic evolution, characterized in that, include: The sea surface geometry modeling module is used to reconstruct a three-dimensional dynamic sea surface using Elfouhaily full spectrum and Creamer nonlinear theory. The polarization scattering calculation module is used to calculate the polarization backscattering coefficients based on a two-scale model that includes large-scale curvature correction and non-Gaussian slope correction. The statistical parameter calculation module is used to dynamically derive the statistical shape parameters of the composite Gaussian distribution based on the bottom-level evolution of the wave spectrum. The Doppler dynamics analytical module is used to perform spectral moment integration of various orders on the two-dimensional wave direction spectrum and calculate the comprehensive Doppler broadening. The coherent echo synthesis module is used to physically couple and fuse slow-time large-scale texture undulations, local polarization RCS distribution, and fast-time Gaussian speckle to generate coherent echoes.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method according to any one of claims 1 to 6.

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