GIM技术在二维介质散射中的应用

Application of GIM in Two-Dimensional Dielectric Scattering

如何利用散射体的几何对称性,使各种矩阵方法求解电磁散射问题所需的存储量和计算时间减少,是当前计算电磁学领域中具有理论和实际意义的重要课题。本文针对谐振频段的TM波对介质柱体的散射问题,采用矩阵方法与GIM(广义镜像法)技术相结合的算法,通过构造虚拟的对称源与反对称源和运用叠加定理,成功地将原问题的求解转化为只在其1/4的边界上进行求解,由此达到了减少矩阵元和节约运算时间的目的。通过理论分析和具体算例的检验,并与MOM计算结果比较,证实了该方法在节约计算时间方面有显著优势。

How to use geometric symmetry of the scattering body to reduce storage and computation time requirement in solving electromagnetic problems by matrix method, is a key subject of the computational electromagnetic field, which is of theoretical and practical significance. In this paper, for the scattering problem of dielectric cylinders under TM wave of reso- nant frequency band incidence, we apply the algorithm combined matrix method with GIM （generalized image method）. By constructing virtual symmetric and anti-symmetric sources and applying the superposition theorem, the algorithm successfully transforms solving the original problem into that only on its 1/4 boundary, thus the purposes of reducing matrix elements and saving running time are achieved. Comparing to MOM, theoretical analysis and specific of examples confirm the fact that this algorithm has obvious advantage in reducing running time.