介质体电磁散射的偶极子模型法研究

Dipole model method for dielectric electromagnetic scattering analysis

提出用偶极子模型法来分析介质体的电磁散射。该方法以矩量法和Schaubert-Wilton-Glisson(SWG)基函数为基础,把介质体剖分成一定数量的四面体元。在介质体内,把含有公共面的体元对等效成电偶极子;在介质体表面,把边界面及其对应的体元等效成电偶极子。当等效偶极子单元离观察点大于临界距离时,用偶极子模型法计算阻抗矩阵元素。偶极子模型法简单易操作,不仅能大幅度降低阻抗矩阵的计算时间,还简化了边界条件的处理。数值结果表明了该方法的高效性及与原方法几乎相同的计算精度。

This paper presents the dipole model method for the efficient analysis of electromagnetic scattering from the dielectric body. The proposed method is based on the conventional method of moments （MoM） associated with the Schaubert-Wilton-Glisson （SWG） basis function and the dielectric body is discretized into tetrahe- dral volume elements. In dielectric body, each SWG common face element contai- ning two inner tetrahedrons or boundary face element containing one tetrahedron is viewed as a dipole model. The impedance matrix element is calculated by the dipole model method when the distance between the equivalent dipole element and the observation point is beyond a critical distance. The dipole model method can speed up the matrix impedance filling significantly and simplify the boundary condition treatment on the surface of dielectric body. Numerical results show its high-efficiency and nearly the same computational accuracy compared with conventional MoM.