246 results about "Em scattering" patented technology

The invention provides a control method for optimizing operation of high-power short-pulse microwave equipment, and aims to improve the accuracy of microwave interference signals, the energy utilization efficiency and the system adaptability. The method comprises the following steps: firstly, acquiring position information, motion trail data, electromagnetic scattering characteristics and environmental electromagnetic parameters of a target object; and then, according to the target position prediction data, the electromagnetic scattering characteristics and the environmental electromagnetic parameters, generating a microwave pulse waveform control instruction. And controlling the phased-array antenna array to generate a directional microwave beam based on the control instruction and the target position prediction data. And collecting real-time response data of the target, dynamically updating the target motion trend prediction model according to the real-time response data, and recalculating microwave pulse signal parameters. And finally, according to the updated signal parameters and the target position prediction data, adjusting the transmitting power, the working time sequence and the beam direction of the phased-array antenna array so as to maintain the optimal interference effect, reduce unnecessary energy consumption and improve the stability and adaptability of the system.

The invention discloses a multi-scale sea surface electromagnetic scattering calculation method and device based on marine environment elements and a storage medium, and belongs to the technical field of marine detection and physical remote sensing. The method comprises the following steps: calculating a tension wave sea spectrum according to an Elfouhail sea spectrum in combination with a Longuet-Higgins directional spectrum; a JONSWAP sea spectrum is combined with a Longuet-Higgins directional spectrum to calculate a gravity wave sea spectrum; superposing the tension wave on the gravity wave according to the slope by using a linear superposition method, and calculating a self-adaptive cut-off wave number; the contribution of small-scale waves to scattering is calculated by adopting an integral equation method, mirror scattering of large-scale waves is counted by adopting a Kirchhoff approximation method, and statistics and fusion are carried out on each scale wave according to the self-adaptive cut-off wave number, so that an electromagnetic scattering value is obtained. According to the method, a sea surface geometric calculation method based on real marine environment element driving is adopted, and accurate calculation is performed aiming at sea surface scattering characteristics under different sea conditions in combination with an integral equation method-Kirchhoff approximation electromagnetic scattering calculation model of an adaptive cut-off wave number, so that the calculation precision of scattering intensity is improved.

The invention provides a sparse approximate inverse Shenwei parallel preprocessing method and system for electromagnetic scattering, and relates to the technical field of processor parallel computing, and the method comprises the steps: carrying out the performance hotspot analysis of a sparse approximate inverse preprocessor in an electromagnetic scattering simulation process, and determining a hotspot function of the sparse approximate inverse preprocessor; extracting a sparse matrix vector multiplication operation of a hotspot function, performing master-slave core parallel calculation on the sparse matrix vector multiplication operation, migrating the sparse matrix vector multiplication operation to slave core calculation, and accelerating hotspot calculation by using a heterogeneous parallel sparse approximate inverse algorithm; parallel computing of master-slave core intensive numerical computing tasks is achieved; in the parallel computing process, the slave cores communicate with the master core in a direct memory access mode, and during the period, the master core is in a waiting state to ensure data consistency and communication synchronization until all the slave cores compute distributed tasks.

The invention relates to a physical constraint fused graph structure UNet neural network for long-time time domain difference optical simulation method and system, and the method comprises the steps: 1, randomly constructing a device parameter data set through an FDTD method, obtaining FDTD uniform grid data, and carrying out the data preprocessing; 2, constructing a graph structure Unet model; 3, inputting the device parameter data set into the graph structure Unet model for end-to-end training; 4, predicting electromagnetic field scattering after a long-time light source encountering period is carried out on given device parameters and initial electromagnetic field distribution; and 5, comparing the electromagnetic field distribution of different device shapes, which is predicted for a long time, with the electromagnetic field value calculated by FDTD, and further judging the prediction accuracy of the graph structure Unet network model. According to the method, one-time long-time sequence prediction of electromagnetic scattering is completed by using the graph structure Unet model.

The invention discloses an SAR image generation method based on guidance of a physical scattering model. The SAR image generation method comprises physically guided feature modulation, attribute scattering center feature constraint and generative network training. According to the physically-guided feature modulation, pitch angle parameterized coding and multi-scale convolution are fused by designing a multi-scale attention module PMA, key scattering features are dynamically enhanced, edge attenuation caused by pitch angle changes is compensated, and geometric continuity of linear scattering is kept. According to the attribute scattering center feature constraint, an ASC loss function is provided based on an attribute scattering center model, multi-scale Gaussian filtering is carried out on frequency domain amplitude spectrums and phase spectrums of generated and real images, and the consistency of the position, the strength and the type of a scattering center is constrained through an L1 distance, so that the generated image is ensured to conform to an electromagnetic scattering physical law. And a CycleGAN generative adversarial network embedded with a PMA module is constructed by generative network training, and cross-angle high-quality SAR image generation is realized by combining end-to-end optimization of adversarial loss, cyclic consistency loss and ASC loss. The method provides a high-precision and physically interpretable solution for SAR image generation and target identification.

Aiming at the detection and identification problems of an underwater target, the invention discloses an electromagnetic scattering field calculation method for an underwater cylindrical metal small target, which comprises the following steps of: 1, carrying out geometric and physical modeling on the underwater cylindrical metal small target to be detected, carrying out numerical discretization preprocessing, calculating information of network nodes of geometric and physical models, and calculating the electromagnetic scattering field of the underwater cylindrical metal small target to be detected; constructing a grid model of the underwater cylindrical metal small target; 2, an electromagnetic scattering field of the grid model is calculated through an improved moment method, and electromagnetic scattering field curves of the underwater cylindrical metal small target in different scenes are obtained; 3, an electromagnetic scattering field of the grid model is calculated through an equivalent surface current method, and electromagnetic scattering field curves of the underwater cylindrical metal small target in different scenes are obtained; and 4, comparing the electromagnetic scattering field curves in the two steps, verifying that the shapes and the amplitudes of the two curves are basically consistent in an allowable error range, and detecting and identifying the underwater metal small target according to the action distance and the intersection situation of the target.

The invention relates to an incident wave loading method for simulating ground electromagnetic scattering based on FDTD. The incident wave loading method comprises the steps of solving an attenuation factor at a certain depth of a PML, arranging the side face and the bottom face of a connection boundary CB on the PML, establishing a ground electromagnetic scattering model, connecting the boundary to load an incident wave, and solving an electric field value and a magnetic field value of the loaded incident wave. According to the method, the four side faces and the bottom face of the connecting boundary CB are completely arranged on the PML, incident waves penetrate through the CB to enter the PML in a non-reflection mode, the edge effect generated by truncation of the periphery of the ground is effectively reduced, and the precision of ground electromagnetic scattering calculation is improved. The truncated ground is limited in a CB boundary area, and calculation of a reflection field and a transmission field is avoided. The method does not depend on ground parameters, and electromagnetic scattering calculation of rough ground and layered ground can be achieved.

The invention discloses an arbitrary structure fast electromagnetic scattering analysis method based on time domain finite difference, and the method comprises the steps: obtaining the triangular patch data of a scatterer model, generating an extended bounding box, and improving the adaptability of a complex structure; an initial grid point set is generated by adopting an interpolation method based on a preset grid side length, and grid data is screened and optimized, so that grid division is more accurate, and calculation redundancy is effectively reduced; the optimized grid data is mapped into a three-dimensional array, and a material type and electromagnetic parameter distribution are defined, so that efficient modeling of a complex target is realized; the electromagnetic scattering characteristics are calculated based on time domain finite difference iterative calculation in combination with the surface equivalence principle and the Poynting theorem, the calculation precision and stability are improved, meanwhile, the calculation process is optimized to reduce the storage requirement and the calculation time, and therefore efficient and accurate electromagnetic scattering analysis of any structure is achieved, the calculation efficiency is improved, and the engineering application requirement is met.

The invention relates to the technical field of electromagnetic scattering, in particular to a frequency domain response calculation method and device of an electromagnetic field, equipment and a storage medium. Performing recursive transformation on the time domain basic system equation according to the discrete time domain set and a backward Euler method to obtain a time domain transformation equation and an algebraic matrix equation; carrying out back substitution solving operation on the algebraic matrix equation according to a time domain stepping method and a time domain transformation equation; performing full-time-domain response calculation on the time-domain finite element solution based on a time-domain finite element method to obtain a time-domain base solution; calculating the time domain base solution according to a preset linear superposition principle to obtain a frequency domain response; a continuous problem is dispersed through a backward Euler method, rapid back substitution solution is carried out after factorization for one time, and redundant calculation is reduced; based on a linear superposition principle, phase weighting is carried out to synthesize a time domain base solution, frequency domain response of any frequency is rapidly obtained, frequency-by-frequency repeated calculation is avoided, efficiency is improved, and the method is suitable for broadband high-precision electromagnetic field analysis and has remarkable application value.

The invention discloses a microwave photon radar strong maneuvering target identification method based on small sample incremental learning, and belongs to the field of microwave photon radar maneuvering target identification. Time-frequency dynamic, polarization space and geometric topological features are extracted through a deep learning model, and multi-dimensional joint characterization is realized in combination with a cross-domain attention mechanism; designing a polarization-time frequency adversarial generative network, generating synthetic data conforming to an electromagnetic scattering rule under the physical constraint of a Maxwell equation, and constructing a prototype feature support set through meta learning; a dynamic knowledge distillation framework is introduced, physical consistency loss is utilized to align motion parameters and classification probability distribution of the teacher model and the student model, and lightweight increment updating is realized in combination with gradient importance masks. According to the method, the recognition precision and real-time performance of the strong maneuvering target in a complex electromagnetic environment are remarkably improved, and the method is suitable for high and overspeed maneuvering target recognition.

The invention discloses a three-dimensional target electromagnetic scattering calculation method and system based on point cloud and machine learning, and relates to the technical field of electromagnetic scattering calculation. The method comprises the following specific steps: photographing a three-dimensional target to obtain two-dimensional image data; performing three-dimensional reconstruction on the two-dimensional image data by combining a point cloud technology with a deep learning technology to obtain a three-dimensional point cloud model; converting the three-dimensional point cloud model into a grid model based on a greedy triangulation algorithm; establishing an integral equation of a three-dimensional target according to the grid model in combination with an electromagnetic principle; solving the integral equation to obtain the surface induction current of the three-dimensional target; and calculating a scattering field based on the surface induction current of the three-dimensional target, and completing electromagnetic scattering characteristic calculation of the unknown three-dimensional target. According to the method, the point cloud technology and deep learning are combined for model generation, a two-dimensional image dimension raising method is used for replacing traditional CAD modeling and laser radar scanning, and the three-dimensional target electromagnetic scattering modeling efficiency is improved.

The invention provides a low-scattering carrier for darkroom background level evaluation test, and relates to the technical field of target far-field electromagnetic scattering characteristic test, the low-scattering carrier is a hollow structure formed by seamless connection of an upper surface and a lower surface; the upper surface comprises a plurality of smooth curved surfaces with continuous curvatures, and the lower surface is a smooth plane; the forward direction of the low-scattering carrier is a sharp needle-shaped tip; and the lower surface is provided with a circular truncated cone hole for embedding a two-dimensional rotating top at the top end of the metal bracket and a connecting structure for connecting and fixing the two-dimensional rotating top. The forward direction of the low-scattering carrier provided by the invention is a sharp needle-shaped tip, so that the low-scattering carrier can be ensured to have a low-scattering characteristic in a relatively wide angular domain range in the forward direction, strong RCS scattering of the two-dimensional rotating top can be shielded, the RCS of the metal bracket can be measured more accurately, and a more accurate darkroom background level can be further obtained.

The invention discloses an internal and external solving method for obtaining electromagnetic scattering characteristics of a cavity-containing target, and relates to the technical field of electromagnetic fields and microwaves, and the method comprises the following steps: decomposing a cavity-containing structure into a cavity internal part and a cavity external part, and building a Huygens equivalent surface on the aperture surface of the boundary between the cavity internal part and the cavity external part; the consistency of electromagnetic modeling solutions before and after internal and external partitioning is ensured by utilizing continuity conditions of current and an electromagnetic field; different solving methods are selected in the inner structure and the outer structure respectively, the interior of the cavity is calculated by combining a cascade method with a rapid direct solving technology, the exterior of the cavity is calculated by adopting a parallel multilayer rapid multi-pole algorithm, and finally, iterative solving of the inner region and the outer region is carried out by utilizing an iterative algorithm, so that the RCS scattering characteristic of the whole cavity-containing structure meeting the calculation requirement is obtained. According to the method, the flexibility of electromagnetic scattering modeling of the target with the cavity is improved, the problem of internal resonance caused by a cavity structure is solved, and the electromagnetic scattering solving capability of the target with the cavity is remarkably improved.

The invention discloses an electromagnetic scattering calculation method based on deep learning under the condition that the shape and electrical parameters of a scatterer are not completely known. The electromagnetic scattering calculation method comprises the following steps: step 1, inputting electrical parameters of a known part of the scatterer, such as relative dielectric constant and magnetic conductivity, an incident field, a small amount of scattered field (observation / measurement) data and position coordinates of a to-be-solved scattered field; 2, solving an internal total field under the condition that only the known part of the scatterer exists and the unknown part does not exist by adopting a moment method; 3, inputting a small amount of scattered field (observation / measurement) data, an internal total field under the condition that only the known part of the scatterer exists and the unknown part does not exist, and the electrical parameters of the known part of the scatterer into a deep learning neural network, and obtaining the electrical parameters of the unknown part of the scatterer through the network, such as a relative dielectric constant and magnetic conductivity; 4, inputting the internal total field under the condition that only the known part of the scatterer exists and the unknown part does not exist, the electrical parameters of the unknown part of the scatterer and the electrical parameters of the known part of the scatterer into another neural network, and obtaining the internal total field of the complete scatterer through the network; and 5, calculating a total field or a scattering field at any position according to a moment method. According to the method, prediction of the scattering characteristics of the scatterer of which the shape and the electrical parameters are not completely known can be completed under the condition that only a very small amount of scattering field (observation / measurement) data is needed.

The invention relates to the technical field of underwater target detection, in particular to a single-transmitting multi-receiving underwater metal small target electromagnetic induction detection method, which comprises the following steps: planning a detection route below an underwater metal small target to be detected according to different operating distances and different intersection angles; a single-transmitting multi-receiving antenna system composed of a transmitting antenna and a plurality of receiving sensors is fixed on an underwater vehicle to form an underwater detection device; an underwater detection device is controlled to pass through the lower part of the underwater metal small target according to a detection route, a transmitting antenna continuously radiates low-frequency electromagnetic waves to the outside, and a plurality of receiving sensors receive signals; performing data processing on the signals received by the receiving sensors to obtain electromagnetic scattering field information of the underwater metal small target, and performing visualization processing to obtain a target passing characteristic curve; and performing imaging operation to obtain a three-dimensional contour image of the underwater small metal target, thereby efficiently, accurately and reliably identifying the shape of the underwater small metal target.

The invention provides a metasurface structure and a metasurface structure preparation method, and relates to the technical field of electromagnetic wave regulation and control. The metasurface structure comprises a frequency selection layer, an isolation layer and a reconfigurable gradient impedance layer, the frequency selection layer is located above the isolation layer; wherein the frequency selection layer is used for receiving a first electromagnetic wave incident at a first angle and inhibiting the echo intensity of scattering of the first electromagnetic wave; the reconfigurable gradient impedance layer is located below the isolation layer; wherein the reconfigurable gradient impedance layer is used for receiving a second electromagnetic wave incident at a second angle and inhibiting the echo intensity of scattering of the second electromagnetic wave; wherein the first angle is smaller than the second angle. According to the application, the echo intensity of mirror scattering is suppressed through the frequency selection layer, and the echo intensity of non-mirror scattering is suppressed through the reconfigurable gradient impedance layer, so that electromagnetic scattering suppression of a wide angular domain is realized.

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 relates to a multi-target structured scene electromagnetic calculation method based on a bounce ray algorithm, and the method comprises the steps: generating a corresponding ray tube based on a surface element for a structured complex scene; ray tube tracking is accelerated by adopting a BVH method; and completing ray tube electromagnetic calculation by adopting a GPU parallel calculation mode to obtain an electromagnetic scattering characteristic result corresponding to the structured complex scene. Compared with the prior art, aiming at single-target and multi-target structured scenes, a bounce ray (SBR) method is developed, a ray tube is constructed through a triangular patch, ray tracing is carried out based on forward and backward rays, a hierarchical bounding volume acceleration tree structure is adopted in the ray tracing process to improve the calculation efficiency of the SBR method, GPU acceleration calculation is adopted in the scattered field calculation process, and the calculation efficiency of the SBR method is improved. The bottleneck that a traditional moment method is low in calculation efficiency when processing a large scene and a physical optical method is limited in calculation precision can be broken through, and the calculation efficiency and the calculation precision are effectively improved.

The invention relates to the technical field of electromagnetic scattering characteristic analysis and modeling, in particular to a scattering center establishing and correcting method based on a geometric model and reference data. The method comprises the following steps: inputting a target geometric or grid file, and extracting geometric features of a plane, an edge and a curved surface to construct an initial scattering center model; inputting electromagnetic scattering reference data of the same target, solving a scattering center correction coefficient by adopting a pseudo-inverse or Tikhonov regularization method, and optimizing an initial model; and outputting an optimized scattering center model with angle and frequency expansibility. According to the method, the electromagnetic scattering characteristics of metal and coating type complex structure targets in single-station, double-station and full-polarization scenes can be uniformly represented, and the problems of insufficient model precision, incomplete types and high data dependence degree in the prior art are solved; the method achieves the excellent effects that the RCS root-mean-square error is smaller than 2dB and the high-resolution imaging structure similarity exceeds 90% in typical target modeling, and is suitable for the fields of target characteristic simulation and characteristic extraction and recognition.

The invention discloses an improved method for calculating grazing incidence sea surface back scattering through a small slope approximation method, and belongs to the technical field of sea surface electromagnetic scattering calculation, and the method comprises the following steps: S1, determining the wind speed of each stage of sea condition, and calculating the seawater dielectric constant; s2, generating sea surface geometry by using a linear filtering method based on a sea wave spectrum according to the determined wind speed; s3, introducing a conical incident wave; s4, introducing an edge geometric attenuation function; and S5, calculating sea surface back scattering by using an approximate integral formula of a small slope approximation method. According to the improved method for calculating grazing incidence sea surface back scattering through the small-slope approximation method, the edge geometric height is attenuated to 0 by applying the edge geometric attenuation function, so that the situation that the height fluctuation of the sea surface edge is close to an incident wave energy central axis is avoided, the problem that the calculation result is large under grazing incidence is solved, and the calculation efficiency is improved. And meanwhile, the calculation result is more accurate.

The invention relates to the technical field of electromagnetic scattering, in particular to an electromagnetic scattering characteristic prediction method and device, equipment and a storage medium. The invention discloses an electromagnetic scattering characteristic prediction method, and the method comprises the steps: carrying out the joint construction of a target structure parameter, a material electromagnetic parameter, and an incident wave parameter according to a preset mapping function, so as to obtain a joint output vector; performing simulation processing on the joint output vector according to a simulation method; training a preset incremental network model according to the simulation result and the simulation data set to obtain an updated main network model; acquiring real-time structure scene parameters, and predicting the real-time structure scene parameters according to the updated main network model to obtain electromagnetic scattering characteristics; comprehensive parameters are obtained, multi-source data are fused, a training data set is generated through simulation, an incremental network model is dynamically optimized, conventional recognition and new parameter adaptation are considered, the main network is updated, the electromagnetic scattering characteristics are predicted in real time, efficient support is provided for engineering such as radar detection, and the research and development quality and efficiency are improved.

According to the electromagnetic stealth metasurface design method universal for any frequency band, the pattern area of the metasurface unit is divided into the grids, each grid can be pasted or not pasted, and therefore ever-changing paster patterns can be formed, the combinations are optimized through the particle swarm optimization, and the expected electromagnetic scattering characteristic is achieved. The design method comprises the two steps of metasurface unit optimization design, metasurface modeling and simulation verification. The metasurface unit optimization design is an automatic optimization design process following a particle swarm algorithm, m different metasurface units can be obtained, and the m different metasurface units present specific phase gradients on a center frequency and a neighborhood frequency band; the metasurface can be formed by selecting the metasurface units from the m different metasurface units. The invention aims to provide an electromagnetic stealth metasurface design method universal for any frequency band. According to the method, the metasurface unit combination meeting the requirement can be fully automatically generated only by giving the target frequency band and setting a small number of parameters according to the rule, and the requirement for human intervention is reduced to the maximum extent.

The invention relates to the technical field of electromagnetic wave detection and imaging, and discloses a radar target echo generation method based on a physical information neural radiation field, which effectively improves the physical consistency of generated echo signals, accurately simulates the energy attenuation characteristics at different observation angles, and improves the radar target echo generation efficiency. The problem of signal completion under the sparse view angle condition is solved. The signal generated by the method is highly matched with measured data in the aspects of amplitude distribution, phase continuity and energy envelope form, a reliable data basis is provided for radar target identification and feature analysis, and the perception capability of a network on target geometric details is enhanced through high-dimensional position coding. Therefore, the generated echo signal can accurately reflect the spatial distribution characteristics of the scattering center. Meanwhile, due to the introduction of the multi-frequency coding sequence, the network can adaptively capture electromagnetic scattering characteristics under different scales, and a reliable technical means is provided for echo generation of a complex target.

The invention discloses a river water level inversion method taking altimeter footprint heterogeneity into consideration. The method comprises the following steps: acquiring an observation waveform of an SAR altimeter; space geometric parameters are calculated through footprint gridding and observation geometric modeling; constructing a water distribution scene based on the water mask and the river network, and classifying the water into a main river channel, a flood area and an adjacent isolated water body; electromagnetic scattering numerical integration is carried out based on the differentiated surface roughness parameters, and a simulated echo waveform is generated; waveform retracking and parameter inversion are realized through coarse grid search and local optimization solution; calculating an absolute water level and carrying out geophysical correction; performing multi-index quality control based on the interpretation rate of the analog waveform and the residual whitening degree; and finally outputting a water level product. According to the method, the defects of insufficient inversion precision and robustness of an existing method in a complex earth surface mixed scene are overcome, and the accuracy, reliability and physical interpretability of inland river water level monitoring are remarkably improved.

The invention relates to a target electromagnetic scattering test supporting method combining a metal support and a foam support, and relates to the field of electromagnetic scattering testing. A ground rotary table is used for bearing a target and supporting a structure to do azimuth rotation; the metal support and the foam support are combined to support a target, and the pitching angle of the target can be adjusted by adjusting the height of the foam support. The metal support rotating equipment rotates the metal support, so that the lowest electromagnetic scattering direction of the metal support is always aligned with the antenna, and the test influence is reduced; the pulse triggering device provides pulse signals for the metal support rotating device based on the rotating position of the ground rotary table to serve as reference for direction adjustment, and the method has the advantages that background clutters are reduced while the attitude and orientation of the to-be-measured target are accurately controlled, and the target erection safety is improved.

The application discloses a kind of based on three-dimensional particle special effect's airborne chaff bomb simulation method, contain the following steps: chaff individual particle modeling: based on three-dimensional particle special effect technology, simulate the motion trajectory of single chaff, the motion characteristics of chaff cloud and chaff electromagnetic scattering characteristic RCS;Complex environment modeling: including meteorological environment simulation model and electromagnetic environment simulation model;Particle special effect driven simulation calculation: under the action of the chaff individual particle model and complex environment model, first, each chaff individual is particleized;Then real-time calculation is carried out;Finally, radar wave irradiation analysis is carried out;Three-dimensional dynamic visualization output: the distribution and interference effect of chaff bomb under different height and environment are realized Real-time display.The application can highly realistic simulate the explosion, diffusion, disappearance etc. of chaff bomb in launching, including the motion trajectory of chaff bomb, diffusion distribution form and the effect of radar scattering.

The present application relates to the field of electromagnetic numerical calculation, and discloses a kind of method for solving electromagnetic scattering based on adaptive block Krylov subspace base function, method includes the following steps: step one: target region is carried out adaptive region decomposition, and target subdomain is obtained;Step two: target subdomain is expanded, and extended subdomain is formed;Step three: using optimized extended subdomain, the solving calculation of electromagnetic scattering is carried out.The main advantage of the present application is that the efficiency of constructing Krylov subspace base function is higher by using adaptive block technology, which significantly reduces the generation time of Krylov subspace base function based on block, optimizes the block expansion of subdomain, improves the solving calculation time, uses clustering algorithm to carry out region decomposition on the calculation target, and uses the average distance of clustering data points to cluster center to expand each subdomain to ensure the continuity of current, which not only ensures the calculation accuracy, but also improves the construction efficiency of base function, significantly reduces the generation time of Krylov subspace base function based on block.

The application discloses a complex lunar surface scattering coefficient image simulation method and system based on multiple data jointing, and the method comprises the following steps: firstly, terrain camera data is used to acquire terrain height data of a special geological structure of the moon as model geometric information input; secondly, a lunar soil weathering layer electromagnetic scattering model is established by using a vector radiation transfer theory and a lunar surface stone double-component method to simulate the interaction between electromagnetic waves and lunar rocks, the lunar surface, weathering layer particles and the subsurface; finally, a radar imaging mechanism is simulated based on a mapping projection algorithm, the scattering coefficient on each scattering facet is calculated by using the electromagnetic scattering model, and the scattering coefficient is mapped to an imaging area by using a ray tracing method, a shadow judgment method and the like, so that the scattering echo of each region of the complex lunar surface is rapidly estimated, and the fast scattering coefficient image simulation is realized.

The present application belongs to the technical field of stealth design of aircraft shape and structure, and discloses a surface wave electromagnetic scattering characteristic quantitative analysis method based on a two-port transmission model. The surface wave electromagnetic scattering characteristic quantitative analysis method based on the two-port surface wave transmission model has an electromagnetic discontinuous structure. By loading the electromagnetic discontinuous structure, the scattering parameters of the port network are monitored, and by changing the structural parameters of the electromagnetic discontinuous structure, the influence of the structural parameters of the electromagnetic discontinuous structure on the surface wave scattering characteristic is quantitatively studied. The surface wave electromagnetic scattering characteristic quantitative analysis method can separate the spatial electromagnetic scattering component when the spatial electromagnetic wave is directly irradiated, and can analyze the electromagnetic scattering characteristic of the surface wave in the discontinuous electromagnetic structure alone, thereby laying a foundation for studying the surface wave electromagnetic scattering characteristic of the electromagnetic discontinuous structure such as a curved surface, a gap and a step, and providing guidance for the stealth design of the aircraft shape and structure.