Research On Wide-band Electromagnetic Scattering Of Objects Based On General Characteristic Function Method

The analysis of wide-band electromagnetic scattering characteristics of objects plays an important role in radar detection,target recognition and other technological developments.Using the method of moments to analysis the wide-band electromagnetic scattering characteristics of the target requires adopt frequency point analysis one by one,which takes a long time to calculate and take up a large amount of memory.Besides,some complex targets cannot be calculated.Therefore,how to propose an efficient numerical algorithm for accurate analysis of wide-band electromagnetic scattering of conductor targets becomes a hot topic in electromagnetic theory research.Based on the moment of method,this paper studies the wide-band electromagnetic scattering of the target.Aiming at the ultra-wideband characteristics basis function method exits some problems such as low computational efficiency and large memory usage.This paper proposes a general characteristics basis function method,which will improves the construction of characteristic base function and removes the redundant calculations exits in low frequency points.Firstly,a general characteristics basis function method is proposed for improving the accuracy of calculation in low-frequency point.This method considers the coupling function between sub-domains,and computes the secondary characteristics basis function,then uses the singular value decomposition technique to remove the linear correlation of the basis function.Examples certified the improved method can greatly reduce the calculation error in the low frequency point.Secondly,when analyzing the electromagnetic scattering characteristics of the target,using the general characteristic basis function method need to set enough incident plane wave excitations which will make the computational efficiency decline.Thus,the singular value decomposition is proposed to remove the redundant in the incident excitations,which can reduce the number of excitations,speed up the base function generation speed and decrease the memory requirements.At the same time,the problem of reconstructing the reduced matrix needs to be reconstructed for each frequency point in the frequency band for the universal feature basis function method,and an effective method for the general characteristic basis function method combined with the model parameter estimation technique(MBPE)is proposed,which sets some sampling frequency points,applies a general characteristics basis function at each sampling point,so that it can be constructed the reduction matrix at the sampling points,and the time of RCS calculate time will be reduced.At last,aiming at the problem that the traditional general characteristics basis method has redundant calculation at low frequency points,an adaptive construction of general characteristics basis method is proposed.The method divides the frequency band into multiple sub-bands,and constructs a general characteristics basis function at the highest frequency point of each sub-band,so that sub-bands can use their respective general characteristics basis functions to analyze the wide-band electromagnetic scattering characteristics of target.This method effectively reduces the computational complexity of the low-frequency point,reduces the dimension of the reduced matrix,increases the speed of the solution and reduces memory consumption.