一种计算有耗媒质中跨界目标电磁散射的高效算法  

An Efficient Method for Calculation of the Electromagnetic Scattering from 3D Objects Embedded in Lossy Medium

作　　者：宋铮[1] 马恒民[1] 邵亚勇[1] 王良良[1] 孙万晶[1] 

机构地区：[1]脉冲功率激光技术国家重点实验室,电子工程学院,合肥230037

出　　处：《微波学报》2012年第5期17-23,共7页Journal of Microwaves

摘　　要：为了克服传统离散复镜像法计算有耗媒质中索莫菲尔德积分的不足,提出了一种基于增强离散复镜像法的插值算法。当场点和源点位于分界面两侧时,谱域格林函数中同时包含场点和源点位置坐标,传统二级离散复镜像法无法一次拟合复指数参数,考虑将谱域核函数对场点坐标分离,然后建立复镜像参数随源点坐标的一维插值表,从而可以对复镜像参数进行插值运算;当场点和源点均位于有耗媒质中时,二级离散复镜像法的采样路径会带来错误,提出对谱域核函数进行形式变换再进行求解,从而使插值法适合有耗媒质中格林函数的计算;为了扩大传统二级离散复镜像法的横向计算距离,在对复镜像参数进行复指数级数拟合时,选择增强离散复镜像法的采样路径。该方法同传统对格林函数进行插值的方法相比,在计算复杂度降低的同时,效率和精度都获得了大大提高。In order to overcome the difficulties of the conventional two-level discrete complex image method （2-DCIM） in calculating the Sommerfeld integrals（SI） in the lossy medium, the interpolation method that is based on the enhanced dis- crete complex image method （E-DCIM） is presented. When the points of the field and source are located in different sides of the interface, the complex image parameters can not be derived by the 2-DCIM at one time for the spectral green functions are treated as independent on the field, then the one-dimensional interpolation table of the complex images related to the source point is established in order to calculate the parameters of the complex images ; When the points of the field and source are both embedded in the lossy medium ,the way of conventional DCIM will lead to wrong results. In order to avoid this error, the spec- tral green functions are reformulated to be suitable for the calculation in the lossy medium. In order to enlarge the transverse distance, the way of the E-DCIM is adopted to fit the parameters of the complex image. Compared to the traditional method, the proposed method reduces the complexity, at the same time, the efficiency and accuracy are improved too.

关 键 词：索莫菲尔德积分 离散复镜像法 插值算法 有耗媒质 

分 类 号：TN011[电子电信—物理电子学]