Modal Decomposition Equivalent Circuit Method Application for dual Frequency FSS Analysis

An application of a modal decomposition equivalent circuit method (MDECM) for analysis of more complex structures like dual frequency FSS has been proposed. The method is based on the equivalent circuit approach and has been recently extended to deal with complicated FSS geometry. Now, the method is able to take into account thick dielectric substrates. What is more important, an initial estimation of the field distribution in a slot aperture can be expressed in terms of two modes despite only one in the fundamental method definition. Theoretical study of FSS composed of dual ring slot elements has revealed a good agreement in comparison with CEM software and periodic method of moments (PMM).