Multimodal variational analysis of quasiplanar waveguide discontinuities

Multimodal variational analysis will be presented for step discontinuity of some commonly used quasiplanar structures. Appreciable reduction in the computation time and computer memory space can be obtained by handling differently the modes which can be accessible from a certain distance to the discontinuity plane and those localized. An analysis program developed in FORTRAN on a PC computer will be applied to microstrip, finline and coplanar discontinuities, and compared to previously published results and experiments.