MODELING OF CASCADED COPLANAR WAVE-GUIDE DISCONTINUITIES BY THE MODE-MATCHING APPROACH

Cascaded coplanar waveguide discontinuities with transverse dimensions in the order of some micrometers are analyzed by the mode-matching an d generalized scattering matrix method. This approach permits a full-w ave analysis of the electromagnetic field also in the metallic regions , Compared with full-wave analysis assuming perfect conductors and a s ubsequent loss computation based on the surface impedance model the ac curacy is considerably enhanced. The mode-matching method is revisited in the context of a network representation of discontinuities. The im plications of Tellegen's general network theorem on the mode-matching method, particularly on the testing functions, are investigated, Furth ermore, the mode-matching method is related to the equivalence princip le applied to discontinuites and to the continuity condition of voltag e and current of quasi-TEM waves in the static approximation.