并矢格林函数在圆柱坐标系中的本征展开及其在几何绕射理论中的应用

并矢格林函数在圆柱坐标系中的本征展开及其在几何绕射理论中的应用 DYADIC GREEN’S FUNCTION EIGENFUNCTION EXPANSION IN CYLINDRICAL COORDINATES AND IT’S APPLICATION IN GEOMETRICAL THEORY OF DIFFRACTION 柯亨玉 Ke Hengyu 1 first-author 黄锡文 Huang Xiwen 1 武汉大学空间物理系 武汉大学空间物理系 Department of Space Physics, Wuhan University Department of Space Physics, Wuhan University 本文首先利用振子辐射场与并矢格林函数之间的关系导出了并矢格函数矢量波函数展开式。应用复变函数方法求圆柱矢量波函数径向谱域积分,求出了圆柱坐标系中并矢格林函数本征波函数展开式。文章还研究了并矢格林函数方法在几何绕射理论中的应用,给出了导电圆柱表面电振子在高频大电尺寸条件下几何绕射理论幅射场公式。对这一典型问题几何绕射理论结果的推广,得到了一般凸曲面导体振子辐射场的几何绕射理论公式。 In this paper, the eigenfunction expansion of dyadic Green’s function in cylindrical coordinates are investigated based on the relation between dyadic Green’s function and radiation field which is excited by an electric dipole. The dyadic Green’s function can be expressed by dyadic vectors of the cylidrical vector wave functions in cylindrical coordinates. Then, the eigenfunction expansion of the dyadic Greeris fuuetion can be obtained by calculating radial spectral integral. As an example, the geometical theory of diffraction （GTD） for electromagnetic field is given by dyadic Green’s function technique. An approximate asymptotic solution of GTD is given for electromagnetic field which is excited by an electric dipole on an electrically prefectly conducting large cylinder surface. The dyadic transfer function of the GTD’s solution agrees well with the conclusion given by P. H. Pathak and can be extended easily to a general convex surface. 电磁振子辐射场 圆柱矢量波函数 回路积分 并矢格林函数 几何绕射理论 radiation field of electric dipole cylindrical vector wave functions contour for the integral dyaclic Green’s function geometrical theory of diffraction 1991-02-01 2021-04-01 2