用谱域导抗法推导平面分层介质格林函数的一般表达式

The Derivation of Generalized Expression of Green's Functions for a Multilayered Medium by Using Spectral-Domain Immittance Approach

本文应用谱域导抗法推导了不同源激励产生的电场、磁场格林函数的一般表达式.它的基本思路是,找到电流源、磁流源分别对应的等效传输线.应用传输线理论求出电场、磁场所对应的量,通过坐标变换回到原来坐标系中,求得所需的谱域格林函数.这样问题变成了确定不同等效传输线上的电流和电压,大大简化了谱域格林函数的推导过程,尤其是对于多层介质的情况.本文最后给出了四种不同类型的谱域格林函数,证明了此方法的正确性.

The derivation of general and concise expressions of spectral-domain electric and magnetic Green's functions for a multilayered medium are given by using spectral-domain immi-ttance approach. In the spectral-domain, two equivalent transmission lines are found, which correspond to the electric and magnetic current sources respectively. Spectral-domain Green's functions are then obtained by using transmission-line theory and coordinate transformations. So the determination of the spectral-domain Green's function is accomplished by the investigation of voltages and currents on the corresponding equivalent circuits. Finally, the validity of this method is confirmed by four types of spectral-domain Green's function.