Transmission properties of double-layer FSS with various relative lateral displacements between two surfaces

The transmission characteristics of double-layer ring-loop slot frequency selective surface with relative lateral displacements between their two surfaces are studied at normal and oblique incidence. The transmission properties, including the -1dB bandwidth, the center frequency and the transmission loss are discussed. The results show that as relative lateral displacements increasing parallel with electric field, the -1dB bandwidth will be border, and the transmission loss will be smaller at normal and TE 30° incidence, while both of which are oppositely when relative lateral displacements parallel magnetic field or relative lateral displacements are increasing parallel with electric field or magnetic field at TM 30° incidence. And the relative lateral displacements have little effect for the center frequency.