基于小波矩量法的目标电磁散射快速算法研究

Research into Fast Algorithm of Target Electromagnetic Scattering Based on Wavelet-MoM

矩量法被广泛应用在电磁场数值计算中,然而作为一种求解积分方程的算法,计算过程中引入了格林函数,需要解复杂的矩阵方程,尤其在计算电大尺寸导体目标电磁散射时,会形成一个规模较大的满秩且稠密的阻抗矩阵,求逆复杂,计算时间长并且易发生错误。提出了一种新的方法用来分析电大物体的电磁散射,采用离散小波变换(DWT)使由传统的矩量法得出的矩阵方程稀疏并降低其计算复杂度,同时提出了一种可以高效填充阻抗矩阵的方法——质心切分法。最后基于目标的散射特性,通过仿真实例,与从传统方法中得出的结果进行了比较,计算结果吻合良好,证明了所提出方法的正确性和高效性。

The method of moments(MoM)is widely used in the numerical calculation of electromagnetic fields.However,as an algorithm for solving integral equations,MoM introduces Green’s function in calculation process,and needs to solve complex matrix equations.Especially when calculating the electromagnetic scattering of electrically large conductor targets,a large-scale,full-rank and dense impedance matrix will occur,and it has complex inversion,long calculation time and error-prone.This paper presents a new method to analyze the electromagnetic scattering of electrically large objects,uses discrete wavelet transform(DWT)to make the matrix equations derived from traditional MoM sparse and reduce the computational complexity,at the same time,proposes a new method that can efficiently fill in the impedance matrix—centroid split method,finally,based on the scattering characteristics of target,uses a simulation example to compare the results obtained from the algorithm and from the traditional method.The calculated results are in good agreement,which proves the correctness and efficiency of the proposed method.