The Effect of Finite Conductivity on Frequency Selective Surface Behaviour

The scattering problem for a Frequency Selective Surface (FSS) consisting of an array of patches or a perforated screen is solved. Both penetrable and impenetrable materials with dyadic surface impedance are considered. The problem is formulated directly in the spectral domain where the relevant functional equation is obtained and solved by the Galerkin Method of Moment. Further, an interesting circuit interpretation of the functional equation allows to assess the role played in the scattering problem by the boundary conditions directly in circuit terms. Results which point out the influence of the surface impedance on the frequency response of FSS's are reported.