THE MODAL EXPANSION THEORY APPLIED TO 3-D METAMATERIAL WAVEGUIDES CHARACTERIZATION

In this article, the Modal Expansion Theory (MET) is applied to 3-D metamaterial waveguides. The equivalent surface impedances of the metamaterial are computed thanks to an open software: GetDP, based on a 3-D Finite-Element-Method (FEM). This program is called during the MET algorithm, which allows considering the frequency and incidence angle dependency of the surface impedances of the metamaterial to compute the dispersion diagrams and the field cartography. To validate the dispersion diagrams obtained with this technique, another FEM commercial software (HFSS) is used as a reference.