区域分裂法在电大尺寸柱体电磁散射中的应用

The application of domain decomposition method in scattering by arbitrary electrically large object

基于区域分裂算法 (DDM)提出了一种精确高效的算法。通过沿二维物体表面将原问题分解为若干个相对独立的子问题 ,使得原问题中的稀疏矩阵变换为各子域中带宽极窄的带状阵 ,计算时间从 O(N2 )下降为 O(N)。同时 ,由于每个子域可以单独求解 ,使内存开销从 O(N2 )下降为 O(N/m) (m为子域个数 ) ,从而可以很好地处理电大尺寸或超大尺寸柱体的散射问题。文中成功地计算了周长为 1 0万个波长的几个电大尺寸二维柱体的电磁散射特性 ,并在小尺寸下与矩量法 (Mo M)和频域有限差分法 (FDFD)进行了比较。同时 ,该方法很容易实现并行计算 ,为进一步提高计算效率提供了可能。

A fast and rigorous method is presented for the analysis of arbitrary electrically large problems. The method is combined FDFD with Domain Decomposition Method (DDM). By decomposing the original domain into several independently sub domains, the consumption of computer memory and CPU time decrease from O(N 2) to O(N/m) and O(N) , respectively, where m is the number of sub-domains. So this method can be used for analyzing any problems without restrict. The scattering by several 2 D cylinders with the maximum perimeter of 100,000 wave length are computed and compared with MoM method and FDFD method. Further more, this method is very suitable for parallel computation, that can promote the computational efficiency more.