大型阵列结构电磁散射的P-FFT算法

Pre-correct FFT algorithm for scattering of an large array structure

提出利用预校正的快速傅立叶变换(P-FFT)和矩量法(MoM)快速分析电大阵列结构的电磁散射特性。研究了适合于电大尺寸结构近区和远区场计算的格林函数的快速算法,同时,利用Rao-Wilton-Glisson(RWG)函数作为基函数和测试函数,可以考虑阵列单元任意方向的表面电流或磁流分布,并利用P-FFT加速矩量法的矩阵求解,减少内存需求和计算时间。计算结果表明该方法特别适合于大型阵列电磁散射特性的分析。

The precorrected-fast Fourier transform （P-FFT） based on the method of moment （MoM） is presented to study the scattering by an electrically large array structure. A fast approach of Green＇s functions that is fit for electrically large structure in both near-field and far-field in multilayered media is solved firstly, and then the Rao-Wilton-Glisson （RWG） functions is employed as the basis functions and testing functions with the novelty of both the electrical currents and magnetic currents considered as arbitrary directions in each unit of the array. The P-FFT can reduce the memory requirement and accelerate the matrix-vector multiplication in the MoM solution. The numerical results presented to demonstrate the accuracy and capability of proposed method for the scattering by a large array.