MULTIPLE FREQUENCY-SELECTIVE SURFACES CONSISTING OF RING PATCHES

Frequency selective surfaces composed of planar arrays of ring patches embedded in a stratified dielectric medium are analyzed. The solution of tile scattering: problem is carried out by the method of moments d irectly in the spectral domain. In particular, a new set of basis func tions with divergent behaviour has been used, and the appropriate trun cation criterion for a stable numerical solution is discussed. Design curves of the resonance frequency and of the reflection bandwidth are shown. Finally, the design of a dichroic plate for a diplexer applicat ion in the millimeter wave range is presented.