Modal circuit decomposition of lossy homogeneous uniform quasi-TEM coupled transmission lines

Abstract

This paper presents a detailed analysis and discussion of the conditions on which the realizability of modal circuit decomposition for lossy homogeneous quasi-TEM coupled transmission lines stands. It is shown that the requirement of a real nonsingular modal transformation matrix cannot always be met. With the exception of some limit situations (lossless conductors or very high-frequency operation), equivalent modal circuits can only be obtained, in general, for transmission-line configurations exhibiting very peculiar symmetry properties. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 8–11, 1999