Wideband FSS superstrate for millimeter-wave antenna gain enhancement

A wideband Frequency Selective Surfaces (FSS) which is used as a superstrate for a patch antenna to form a high-gain resonant cavity antenna is presented. This FSS consists of two metal structures separated by a substrate in the middle. It exhibits a wide stop-band in the 60GHz band. Further a panel of this FSS is implemented as a superstrate for antenna gain enhancement. It is observed that a broadband gain enhancement of 5.9dB with variations less than 2dB throughout the operating band is obtained.