104 results about "Scattering cross-section" patented technology

The invention discloses a phased array weather radar calibration method based on a generalized metal ball calibration theory. Comprising the following steps: in a microwave anechoic chamber, collecting two-dimensional antenna pattern data of a phased array weather radar in at least one working mode and pointing to a plurality of different beams; performing numerical integration on the two-dimensional antenna pattern data, calculating a combined beam main lobe solid angle of the transmitting antenna and the receiving antenna, and calculating an equivalent beam width product; calculating a calibration theoretical reflectivity factor of the metal ball based on the product of the theoretical radar scattering sectional area and the equivalent beam width of the metal ball; actual detection echo data of the phased array radar on the metal ball under different working modes and beam pointing is acquired, and an actual reflectivity factor is calculated; and comparing the actual reflectivity factor with the calibration theoretical reflectivity factor to complete calibration of the phased array weather radar. Aiming at the non-Gaussian working mode of the phased array weather radar, the reflectivity factor of the phased array weather radar can be quantitatively evaluated, and the radar detection performance is improved.

The invention discloses an ultra-wideband RCS (radar cross section) reduction metasurface with mixed wave absorption and diffuse scattering and a wave-transparent window, and belongs to the technical field of electromagnetic metamaterials. The metasurface adopts a four-layer cascade structure and comprises a first layer of polarization conversion structure, a second layer of 2.5 D lossy structure, a third layer of Jerusalem cross-shaped lossy structure and a fourth layer of frequency selective surface structure. By loading a lumped resistor at a specific position and adopting a metal through hole interconnection technology, dual functions of radar cross section reduction in a 1-20GHz ultra-wideband and low insertion loss wave transmission in a 8-12GHz frequency band are realized. The structure of each layer adopts a highly symmetrical design and has the characteristic of polarization insensitivity, and meanwhile, by optimizing interlayer air gaps and dielectric material selection, the structure compactness is realized on the premise of ensuring the performance. The method has important application value in the aspect of integration of stealth equipment and a communication system.

The invention discloses a large-scale cluster target electromagnetic scattering analysis method and system based on a parallel equivalence principle, and the method specifically comprises the steps: carrying out the geometric modeling and equivalent surface construction of each target unit in a cluster target, and generating discrete surface element information; starting a parallel computing process, and distributing a target-equivalent face by adopting a greedy algorithm; a calculation process group corresponding to each sub-domain is partitioned according to a two-dimensional Cartesian coordinate grid, a transfer operator matrix between the sub-domains is partitioned according to the same two-dimensional calculation process grid, global parallel iterative solution circulation is carried out, and the equivalent surface flow of the sub-domain is updated; and the converged equivalent surface flow of each sub-domain is used as an equivalent source, and the radar cross section RCS of the whole cluster target in the specified observation direction is synthesized through far-field radiation integration. The method has good parallel expandability and calculation efficiency, is suitable for complex and diverse cluster target scenes, reduces memory requirements and calculation time overhead, improves calculation efficiency, and is high in engineering practicability.

The invention provides a ship detection-oriented multi-source remote sensing image fusion method, a ship detection-oriented multi-source remote sensing image fusion medium and a ship detection-oriented multi-source remote sensing image fusion system, and belongs to the technical field of remote sensing images. Constructing an electromagnetic scattering constraint model based on physical optical approximation and a geometric diffraction theory to calculate a predicted value of the backscattering cross section of the target, introducing a fusion cost function, generating a fusion weight matrix by adopting an adaptive feature weighting model, and performing multi-scale fusion on the image through hypercomplex wavelet transform; and iteratively optimizing the fusion result by using an information diffusion heat conduction equation, and performing physical consistency correction to output an enhanced fusion image, thereby solving the technical problem of poor physical consistency of the fusion result caused by lack of physical model constraint when the synthetic aperture radar image and the multispectral image are fused.

The invention discloses an NRCS determination method for a Ku wave band scatterometer under a rainfall condition, and relates to the field of satellite ocean remote sensing and meteorological detection.The method comprises the steps that the action mechanism of rainfall on radar signals in the atmosphere is considered, and a sea surface radar back scattering theoretical model is constructed based on a wind-generated sea surface wave spectrum and a dual-scale Bragg scattering theory; obtaining a rainfall attenuation coefficient, a normalized radar backscattering cross section contributed by raindrop scattering and dual-polarization normalized radar backscattering cross sections of a C wave band and a Ku wave band based on a sea surface radar backscattering theoretical model; according to the rainfall attenuation coefficient, the normalized radar backscattering cross section contributed by raindrop scattering and the dual-polarization normalized radar backscattering cross sections of the C wave band and the Ku wave band, the normalized radar backscattering cross section of the Ku wave band scatterometer under the rainfall condition is obtained; according to the method, the accurate normalized radar back scattering cross section of the Ku wave band scatterometer is obtained under the rainfall condition.

The invention discloses a method, a system, equipment and a medium for evaluating the gas-bearing property of a water-flooded area, and the method comprises the steps: confirming three pieces of quantitatively measured skeleton information and fluid medium information in a time domain through different minerals and fluid components, and calculating a fast neutron scattering cross section according to pulse neutron logging data; carrying out qualitative identification on the gas reservoir by combining the fast neutron scattering cross section and the stratum hydrogen-containing index; according to the fast neutron scattering cross section, the thermal neutron capture cross section, the hydrogen content index and the respective volume content, a linear equation set is established, and the simultaneous equation set is solved to obtain the content of different fluid components in the stratum. The gas reservoir evaluation method solves the problem that a conventional gas reservoir evaluation method is seriously influenced by detection depth, borehole environment, invasion, low contrast ratio and pore fluid properties, and does not depend on conventional logging curves and electrical characteristics.

The invention discloses a laser radar temperature measurement method and device based on oxygen atom vibration Raman scattering, and particularly relates to the technical field of laser radar atmosphere detection, and the method comprises the steps: calculating a differential Raman scattering cross section value of a to-be-measured altitude in a resonance Raman scattering transition spectral line; constructing a radar parameter equation; determining a relational expression between the ratio of the Stokes Raman scattering signal to the anti-Stokes Raman scattering signal and the temperature; and determining the absolute temperature of the atmosphere at the altitude to be measured based on the differential Raman scattering cross section value of the altitude to be measured in the resonance Raman scattering transition spectral line and the relational expression of the ratio of the Stokes Raman scattering signal to the anti-Stokes Raman scattering signal and the temperature. The method can overcome the problem that observation objects of a traditional method are limited in spatial distribution, is wide in temperature measurement range, is not easily influenced by other scattered signals, and is stable and reliable.

The present application relates to the technical field of microwave measurement and reverberation chamber, and particularly relates to a test model of total scattering cross section of a reverberation chamber stirrer based on mirror principle and application, comprising: constructing a mirror model, and obtaining the number of mirror objects after multiple reflections and the total surface area of the mirror model; obtaining the time constant of the reverberation chamber; obtaining the damping time constant of the stirrer; and constructing the test model of the total scattering cross section of the reverberation chamber stirrer. The present application directly reflects the propagation mechanism of electromagnetic waves in the reverberation chamber and the scattering characteristics of the stirrer on the electromagnetic waves, has a certain guiding effect on the optimization of the stirrer and the test configuration, helps to understand, analyze and reduce the un-stirred energy in the reverberation chamber, and finally realizes the effective improvement of the performance of the reverberation chamber.

The invention provides a satellite-borne SAR radiometric calibration precision evaluation method and system, a medium and equipment, and belongs to the technical field of radiometric calibration, and the method comprises the steps: recognizing and analyzing an error source which affects the calibration precision; selecting a flat area as a calibration field according to the error source; arranging a plurality of standard calibration devices with known radar cross sections in an imaging band according to the satellite top crossing position and the wave position; controlling the satellite-borne SAR to irradiate the selected area at a specified wave position, acquiring and processing scene echo data, and generating an SAR image; according to the SAR image and a known radar cross section, calculating a radar cross section measurement value; and evaluating the satellite-borne SAR radiometric calibration precision according to the measured value of the scattering sectional area and the true value of the scattering sectional area. According to the method, multiple types of error sources in the radiometric calibration link are identified and analyzed, the calibration field is selected and multiple standard calibration devices are arranged based on the error sources, and the actually measured data are compared with the true value, so that the accuracy and credibility of radiometric calibration precision evaluation are improved.

The present invention discloses a method for calculating a photon-atom coherent scattering cross section that takes into account the molecular interference effect. For a specific molecule, the Thomson differential scattering cross section of each element contained in the molecule is first calculated; secondly, a molecular interference function of the molecule to be calculated is obtained based on experimental measurement or molecular dynamics simulation; then, the molecular interference function is used to correct the atomic shape factor of each element contained in the molecule based on the independent atomic shape factor approximation method to obtain an atomic shape factor that takes into account the molecular interference effect; then, the factor is integrated to obtain an integrated atomic shape factor in a continuous energy ACE format database used by a Monte Carlo program; at the same time, the atomic shape factor that takes into account the molecular interference effect is used to correct the Thomson differential scattering cross section to obtain a differential scattering cross section of a coherent scattering reaction that takes into account the molecular interference effect, and the energy angle integration of the modified Thomson differential scattering cross section can be used to obtain a multi-group coherent scattering cross section used by a deterministic program.

This invention belongs to the field of computational electromagnetics numerical simulation and provides a simulation method for electromagnetic scattering of thin-coated targets based on Schur complement preconditions. First, for the IBC scattering target to be solved, equivalent surface current and equivalent surface magnetic current are introduced as independent unknowns. The electromagnetic scattering solution equation is established using SDIE and then discretized. Next, the impedance matrix is ​​decomposed into near-field and far-field matrices using an octree structure. For the near-field matrix, key operator sub-blocks are explicitly assembled and extracted. Then, approximate operators in block diagonal form and Schur complement operators are constructed and approximately inverted. Simultaneously, the diagonal product of intermediate blocks is pre-calculated and stored based on the approximate operators. Finally, the constructed preconditions are applied to the GMRES iterative solver. When the iteration error reaches the preset convergence criterion, the current and magnetic current distributions on the target surface are output. Further calculations of radiation characteristic parameters such as the target's radar cross section are then performed, achieving low-cost, high-efficiency, and easily parallelizable electromagnetic simulation solutions.

This invention relates to the field of RCS testing technology, specifically to an image-domain-based near-field anomalous scattering filtering method. The method first obtains a raw near-field image by near-field imaging of the acquired near-field swept data. Second, based on set anomalous scattering judgment conditions, the anomalous scattering centers are identified and extracted. Then, using a point target as a reference object, the scattering field distribution in the determined filtering area is simulated and reconstructed to generate a new near-field image. Finally, it is determined whether the new near-field image meets the anomalous scattering judgment conditions. If not, a filtered near-field image is generated. By identifying and removing scattering centers that do not belong to the test target from the two-dimensional image generated by the near-field imaging, near-field clutter suppression and higher-precision radar cross section testing are achieved.

The present application relates to a kind of radar scattering cross section test methods based on deep learning and ISAR imaging inversion, the method includes using ISAR imaging test mode to obtain target and calibration body broadband radar scattering echo signal, calibration processing and applying filter-inverse projection imaging algorithm to carry out ISAR imaging, application completes the deep learning model of accurate extraction ISAR image scattering signal area, application FFT transform-interpolation integral ISAR imaging inversion algorithm high-precision inversion reconstruction RCS value, change ISAR imaging aperture center azimuth angle traversal acquisition target all azimuth angle RCS data.The radar scattering cross section test method based on deep learning and ISAR imaging inversion provided by the present application solves the accurate extraction ISAR image scattering area and ISAR image high-precision inversion reconstruction RCS and other test practical problems, expands RCS data acquisition method.

A spherical designer electromagnetic surface plasmon open resonator is provided. The open resonator includes a resonator inner core and a resonator outer shell. The resonator inner core is located in an inner center of the resonator outer shell, and the resonator inner core and the resonator outer shell are coaxial. The disclosure provides a device that implements the superscattering function for incident waves in all incident directions and in all polarization directions, and a spherical open resonator is implemented. The scattering cross section of the disclosure can be more than five times greater than that of a metal sphere of the same size, and the operating frequency can be flexibly designed. By utilizing the characteristic that the scattering cross section of the spherical designer electromagnetic surface plasmon resonator is much greater than its own geometric cross section, the electromagnetic super-scattering device can be implemented.

The application provides a radar scattering cross section (RCS) acquisition method based on CBFM-AIM-EDM, and the implementation steps are as follows: initializing parameters; calculating main characteristic basis functions of each sub-region based on CBFM-AIM; calculating secondary characteristic basis functions of each sub-region based on CBFM-AIM-EDM; constructing a reduction matrix and acquiring the radar scattering cross section (RCS). The main characteristic basis functions and the secondary characteristic basis functions of each sub-region are calculated by using the characteristic basis function method (CBFM), then the RWG basis functions and their divergence on each sub-region can be projected on the matrix grid respectively by using the adaptive integration method (AIM) to obtain the Topelitz matrix, so that the calculation speed is accelerated, the RCS acquisition efficiency is improved under the condition of ensuring the accuracy, and the coupling between two sub-regions of the target is equivalent to the coupling between equivalent dipoles by using the equivalent dipole moment method (EDM), so that the RCS acquisition efficiency is further improved.

This invention belongs to the field of radar signal processing and target detection technology, specifically relating to a statistical scattering method for clutter particles in radar detection. The method includes: acquiring single scattering parameters and simulation control parameters of the clutter particles; dynamically determining the simulation space length based on the single extinction coefficient and asymmetry factor; initializing a quasi-Monte Carlo low-discrepancy sequence; after initializing each photon packet, randomly generating a propagation step size and updating the cumulative propagation step size; when the photon packet does not exceed the boundary, determining whether scattering has occurred based on the single extinction coefficient and cumulative propagation step size; if scattering has occurred, updating the scattering direction based on the Henyey-Greenstein phase function and attenuating the energy weight; employing an adaptive dynamic threshold roulette wheel mechanism to dynamically adjust the survival probability based on scattering efficiency, photon position, and propagation direction, and maintaining statistical unbiasedness through energy weight compensation; after traversing all photon packets, calculating the total transmitted energy and total reflected energy, and calculating the equivalent extinction coefficient and radar cross section. This invention significantly improves simulation efficiency while ensuring statistical accuracy through physically guided importance sampling and a quasi-Monte Carlo low-discrepancy sequence, providing reliable support for radar anti-environmental clutter interference design.

The invention relates to the technical field of neutron transport numerical calculation, in particular to a cross section generation method and device based on flux moment homogenization and transport correction coupling and a storage medium, and the method comprises the steps: S1, building a geometric model of a reactor assembly or lattice cell, carrying out the energy Monte Carlo calculation, and generating a conventional cross section based on statistical data; s2, extracting a spherical harmonic function flux moment and a total reaction rate moment, calculating a total cross section spherical harmonic function correction term, and introducing a conventional scattering cross section to complete flux moment homogenization correction; and S3, exporting a first-order scattering matrix, carrying out transport correction to obtain a transport correction term, and correcting the conventional cross section according to the transport correction term and the total cross section spherical harmonic function correction term to generate a final multi-group cross section. According to the method, the anisotropies of the total cross section and the scattering cross section are synergistically corrected, the calculation precision of the method in the strong anisotropy problem is improved on the premise of keeping the standard cross section data structure, and the compatibility with a widely applied reactor core calculation program is ensured.

The application discloses a phased array weather radar calibration method based on generalized metal ball calibration theory. The method comprises the following steps: collecting two-dimensional antenna pattern data of a phased array weather radar under at least one working mode and multiple different beam directions in a microwave darkroom; performing numerical integration on the two-dimensional antenna pattern data, calculating a combined beam main lobe real solid angle of a transmitting antenna and a receiving antenna, and calculating an equivalent beam width product; calculating a calibration theory reflectivity factor of a metal ball based on a radar scattering cross section of the metal ball and the equivalent beam width product; acquiring actual detection echo data of the phased array radar on the metal ball under different working modes and beam directions, and calculating an actual reflectivity factor; and comparing the actual reflectivity factor with the calibration theory reflectivity factor, thereby completing calibration of the phased array weather radar. The application can quantitatively evaluate the reflectivity factor of the phased array weather radar in a non-Gaussian working mode, and improves radar detection performance.

The application relates to the field of laser radar detection, in particular to a space target laser radar scattering cross section simulation method, device, equipment and medium. The method comprises the following steps: projecting a triangular facet to a pixel plane perpendicular to an incident wave to obtain a projected facet with a depth attribute; regarding a pixel located in the projected facet in a circumscribed rectangle of the projected facet as an area pixel, and calculating a weighted average value of depth values of three vertex pixels according to the relative position of the area pixel in the projected facet to obtain a depth value of the area pixel; selecting an area pixel with the minimum depth value from at least one area pixel corresponding to any pixel in the pixel plane as a visible pixel, and regarding a projected facet with a proportion of the visible pixel to the area pixel exceeding a preset visible threshold as a visible facet; and calculating a laser radar scattering cross section based on the visible facet. The visible pixel is identified by performing pixel-level depth testing on the facet to determine the visible facet, so that an accurate laser radar scattering cross section is obtained.

The invention discloses a near-field test calibration method for a radar cross-sectional area RCS, and the method comprises the steps: carrying out the unified modeling of the overall error of a test system into a system error, and sequentially carrying out the phase correction, distance threshold screening, low-pass filtering, amplitude correction, near-far field conversion and the like of original test data. On the basis, a cascade filtering calibration method capable of decomposing filtering layer by layer is provided and is used for accurately calibrating converted data and effectively inhibiting residual noise and disturbance signals in the data, so that high-precision reckoning amplitude and phase information is obtained. In the calibration filtering process, a cascade least mean square (LMS) algorithm is adopted, and the accuracy and stability of a near-field RCS test result are remarkably improved by inhibiting and filtering uncertain noise in a system layer by layer.

The embodiment of the invention provides a wave absorbing structure, a supporting system and a target radar cross section testing system, and relates to the technical field of electromagnetic measurement. The wave absorbing structure comprises a tubular magnetic material substrate and a low scattering structure arranged on the peripheral wall of the magnetic material substrate; the low-scattering structure comprises a plurality of wave absorbing units, the wave absorbing units are distributed one by one in the length direction of the magnetic material substrate and connected in sequence, and the section, parallel to the length direction of the magnetic material, of the outer side of each wave absorbing unit is in a pointed cone shape; in the length direction of the magnetic material, the outer diameter of the wave-absorbing unit located in the middle is the smallest, and the outer diameters of the wave-absorbing units from the middle to the two ends are larger. According to the wave-absorbing structure, the scattering level of the lifting rope is greatly optimized and the coupling scattering is reduced by combining the low-scattering appearance design and the wave-absorbing performance of the magnetic material substrate according to the scattering characteristic of two lifting ropes and one lifting rope.

The application provides a target radar cross section test method and a verification method thereof, and relates to the technical field of radar stealth test. The test method comprises the following steps: obtaining an RCS amplitude curve and an RCS phase curve of a carrier; obtaining the RCS amplitude curve and the RCS phase curve of a low-scattering target and the carrier; correcting the RCS amplitude and the RCS phase of the low-scattering target and the carrier; and obtaining RCS test data of the low-scattering target through a carrier vector cancellation method. The verification method is used for verifying the effectiveness of the target radar cross section test method. The target radar cross section test method solves the problems of inaccurate cancellation and large evaluation error caused by inconsistent placement postures of the low-scattering target and the carrier.

The invention discloses a method for rapidly identifying the form of a single nanoparticle. According to the invention, an angle scanning reflection dark field scattering microscope (ASDFSM) is utilized, based on the principle of a common reflection dark field scattering microscope (RSDFSM), an imaging light path of the RSDFSM is transformed by utilizing a light barrier, and nanoparticles modified on an interface can be imaged in a large field of view through a low-power objective lens. Due to the anisotropic particles, the scattering intensity of the particles depends on the scattering cross sections of the particles in different directions. Morphological characteristics of the particles in different orientations can be reflected by acquiring an SASI (angle scanning-scattering intensity) curve, and morphological recognition of the nanoparticles is realized by analyzing the relationship between the SASI curve of the nanoparticles and morphologies. The method has the advantages of being simple in operation and large in imaging view field, the morphology of the nanoparticles can be recognized under the condition that the spatial resolution is not improved, and morphology recognition of the nanoparticles can be carried out under the large view field (high flux).

The application belongs to the field of electromagnetic field calculation, and discloses a method for calculating electromagnetic scattering field of moving plasma target based on DGTD. The method firstly models the target to obtain a model file; then calculates the space and time components in the moving coordinate system by using Lorentz transformation formula, and introduces incident wave into the moving coordinate system; then iterates electromagnetic field in combination with the moving plasma model, calculates the near-field data under the moving coordinate system, and inversely transforms the near-field data by using Lorentz transformation to obtain the near-field data under the laboratory coordinate system, and extrapolates to obtain the laboratory coordinate system, Fourier transforms the time-domain incident electromagnetic field to obtain the frequency-domain value, and then solves to obtain the single-station radar scattering cross section (RCS) of the target under the laboratory coordinate system. The application can better fit complex models, is more flexible in the treatment of multi-scale problems, can effectively improve the numerical dispersion phenomenon, and can simulate moving targets with higher speed.

The invention relates to a radar cross section test method based on deep learning and ISAR imaging inversion, and the method comprises the steps: employing an ISAR imaging test mode to obtain broadband radar scattering echo signals of a target and a calibration body, carrying out the calibration processing, and carrying out the ISAR imaging through employing a filtering-inverse projection imaging algorithm, and accurately extracting an ISAR image scattering signal region by using the trained deep learning model, inverting and reconstructing an RCS value with high precision by using an FFT (Fast Fourier Transform)-interpolation integral ISAR imaging inversion algorithm, and traversing by changing an ISAR imaging aperture center azimuth angle to obtain target omni-directional angle RCS data. According to the radar cross section test method based on deep learning and ISAR imaging inversion provided by the invention, the test practice problems of accurate extraction of an ISAR image scattering region, high-precision inversion reconstruction of the RCS by the ISAR image and the like are solved, and an RCS data acquisition method is expanded.

A radar cross-section (RCS) measurement system comprising a reconfigurable intelligent surface (RIS) transceiver positioned relative to a first illumination direction of a target under test (TUT), a RIS reflector positioned relative to a second illumination direction of the TUT, and a controller. The controller is configured to control the RIS transceiver to transmit an electromagnetic (EM) wave towards the first illumination direction of the TUT and the RIS reflector, control the RIS reflector to reflect the EM wave received from the RIS transceiver towards the second illumination direction of the TUT, control the RIS reflector to reflect a scattering of the EM wave received from the second illumination direction of the TUT back to the RIS transceiver, and compute the RCS of the TUT in the second illumination direction of the TUT based on the scattering of the EM wave received from the RIS reflector.

The embodiment of the application provides a spectrum detection method, a spectrum detection system, an electronic device and a storage medium, and belongs to the technical field of spectrum determination. The spectrum detection system is provided with a vacuum cavity, an ion trap device and a laser photodissociation module. The method comprises the following steps: capturing sample molecule ions in the vacuum cavity through the ion trap device, then performing a photodissociation operation on the sample molecule ions in the ion trap device through the laser photodissociation module to obtain target fragment ions. Then, the target fragment ions are irradiated with detection light to make the target fragment ions generate fluorescence signals, then the fluorescence signals of the target fragment ions are detected, and the target photodissociation scattering cross-sectional area corresponding to each dissociation light wavelength is calculated according to the fluorescence signals and the dissociation light wavelengths of at least two different dissociation lights. Finally, the photodissociation spectrum information is obtained according to the target photodissociation scattering cross-sectional areas corresponding to the at least two dissociation light wavelengths. The embodiment of the application can accurately measure the photodissociation spectrum of specific particles.

The application discloses a kind of dispersion type fuel's thermal neutron scattering cross section calculation method and related device, belong to reactor material reaction cross section calculation technical field;The method first constructs the supercell of dispersion type fuel, calculates the Hellmann-Feynman force between each atom of supercell;And according to Hellmann-Feynman force, calculate phonon state density, mean square displacement matrix, dispersion relation and polarization vector;For the thermal neutron scattering law data calculation of fuel material, it can improve the accuracy of thermal neutron scattering law calculation, and then the theoretical value of thermal neutron scattering cross section is calculated;Finally, the actual experimental measurement value is compared with the aforementioned thermal neutron scattering cross section theoretical value, and the input parameters of thermal neutron scattering calculation are corrected according to the error of the two, and then the dispersion type fuel thermal neutron scattering cross section library with higher accuracy is obtained again by the corrected input parameters, and the calculation result is more accurate compared with the prior art.

This invention relates to a method and apparatus for rapid simulation of sea clutter based on the backscattering Morchin model. The method includes: determining a radar illumination area; dividing the radar illumination area into multiple scattering units according to the range ring resolution width and azimuth resolution; dividing each scattering unit into two triangular-like regions, and calculating the scattering cross-section of each triangular-like region using the backscattering Morchin model; obtaining the echo signal of the corresponding scattering unit based on the scattering cross-section of each triangular-like region; and superimposing the echo signals of scattering units on the same range ring to obtain the simulated sea clutter echo signal. This invention solves the problem of rapid sea clutter simulation. The generated simulated sea clutter echo signal exhibits strong temporal correlation, improving the effectiveness and realism of sea clutter simulation, and demonstrating high efficiency for rapid sea clutter simulation.

The invention discloses a self-defined control method and system for a scattering surface of a phased-array antenna based on impedance modulation, and mainly solves the problem that the scattering characteristic of the phased-array antenna cannot be accurately controlled in the prior art. According to the implementation scheme, the method comprises the following steps: collecting a to-be-solved linear array antenna; calculating an array antenna mode item scattering field under any load by using each unit radiation field in the array, and calculating an array total scattering field and an antenna total scattering field RCS value according to the scattering field and the structure mode item scattering field; constructing a fitness function containing deviation between a target value and an actual scattering value, and iteratively optimizing non-uniform terminal impedance of an array antenna mode item scattering field; and the optimized terminal impedance value is utilized to change a load reflection matrix in an antenna mode item scattering field to modulate the antenna mode item scattering field so as to offset the structure mode scattering field, so that the total scattering field RCS reaches a specified target value, and the impedance is utilized to design an antenna array comprising an impedance matching network. The method can achieve the precise control of the scattering characteristics of the phased-array antenna, and can be used for the control of the radar cross section.