A frequency selective surface using aperture coupled microstrip patches

A new type of frequency-selective surface (FSS) that uses two back-to-back arrays of aperture coupled microstrip antennas is described. The resulting bandpass response is relatively narrowband, which may be an advantage in applications where frequency-selective surfaces are used as radomes, as dichroic surfaces, or for antenna radar cross section (RCS) reduction. The frequency response can be controlled, to some extent, by adjusting the size of the coupling apertures. Also, by proper arrangement of the coupling apertures, the FSS can be made to pass linear or dual-polarized waves. A full-wave infinite array analysis of this FSS has been completed, and calculated results showing the effect of aperture size on the transmission coefficient are presented, along with data on the variation of the transmission coefficient with frequency and incidence angle. Measurements from waveguide simulators were used to confirm the theory.<>