三维磁各向异性目标电磁散射的MOM-CGM-FFT方法

Application of MOM-CGM-FFT Method to Scattering from Three-Dimensional Magnetic Anisotropic Scatterers

本文给出了研究任意形状三维磁各向异性目标电磁散射问题的一种混合计算方法。该方法以磁场作为未知函数建立频域体积分 微分方程 ,使用脉冲基函数和点匹配函数的矩量法 (MOM)将之转化为线性代数方程组。在求解过程中应用共轭梯度法 (CGM)和快速傅立叶变换 (FFT)相结合的方法降低所需计算机内存和CPU时间。对均匀磁各向同性球的数值计算结果与相应Mie理论结果吻合较好。在此基础上给出了磁各向异性球和立方体的雷达散射截面。计算结果表明该计算方法兼容性强 ,是一种求解三维电磁散射问题的有效途径。

A mixed method for computing electromagnetic scattering from arbitrarily shaped, three dimensional (3D) magnetic anisotropic bodies is presented. The method is based on a general volume integro differential formulation of the scattering problem, and consists of the numerical method by method of moment (MOM) with pulse basis functions and a Dirac δ testing function. The conjugate gradient method (CGM) and fast Fourier transform (FFT) technique are used to reduce the necessary memory and CPU time. The numerical results are validated by comparing the radar cross section (RCS) of magnetic isotropic sphere with those obtained using Mie series method. The RCS of a magnetic anisotropic spheres and cub are also calculated using the present method. The numerical results indicate that the method has strong capability to calculate the RCS of three dimensional objects.