Analysis of a dual, non-similar, screen FSS using simple cascading procedures

A dual-screen, four-frequency FSS (frequency selective surface) has been proposed for use in the CRAF/Cassini mission to Saturn and its satellites. A numerical experiment was conducted with the goal of determining the conditions under which a simple zeroth-order scattering (S) matrix can be used to model the dual-screen FSS accurately. Using a zeroth-order S-matrix, the unit cell periodicity dependence of the scattering parameters is eliminated, thus allowing the use of simple circuit-type techniques to analyze the dual-screen system. In order to verify the results of the numerical experiments, a breadboard model of the system was constructed. It was found that the numerical predictions using the zeroth-order S-matrix were in good agreement with the measured results. It was also found that the two FSS systems could be cascaded without disturbing the desired frequency responses of the individual screens.<>