Guided-wave characteristics of CPW transmission line metamaterials: effective per-unit-length parameters

The objective of this paper is to numerically de-embed the two effective per-unit-length parameters of 1D CPW metamaterials with simultaneously series inductive and shunt capacitive elements that are internally etched on a dielectric substrate. First, these two CPW lumped elements are modelled and their T- or π-network parameters are extracted. Then, the complex characteristic impedance and propagation constant of this CPW transmission line metamaterial are obtained and plotted as a function of frequency to entirely and deeply illustrate the guided-wave characteristics over a wide frequency range. Finally, finite-length CPW metamaterials, launched by two uniform CPW feed lines, are characterized on the basis of the cascaded transmission line theorem and predicted S-parameters are verified by those from the ADS simulator.