Exploration of the properties of the mixed-mode S-parameters

The paper targets to explore the properties of the mixed-mode S-parameters, which are widely used in the computer PCB and wireless RF industries and have not received serious discussion in the currently published literature. In this paper, in order to compare these properties with the corresponding ones defined in the conventional single-ended S-parameters, we have first developed the symmetric and unitary properties in terms of the mixed-mode S-parameter matrix. Next, we have developed a method to deal with the reference plane shift, which is expressed in a mixed-mode S-parameter fashion for the cases of uncoupled connection transmission lines. To validate the developed mixed- mode S-parameter properties, we have herein analyzed a network constructed by a pair of uncoupled transmission lines.