Spectral Domain Immitance Approach for Dispersion Characteristics of Generalized Printed Transmission Lines

A simple method for formulating the dyadic Green's functions in the spectral domain is presented for generalized printed transmission Iines which contain several dielectric layers and conductors appearing at several dielectric interfaces. The method is based on the transverse equivalent transmission line for a spectral wave and on a simple coordinate transformation. This formulation process is so simple that often it is accomplished almost by inspection of the physical cross-sectional structure of the transmission line. The method is applied to a new versatile transmission line, a microstrip-slot Iine, and some numerical results are presented.