High Gain Resonant Cavity Antenna Integrated with Frequency Selective Surface Radome Absorber

A high gain resonance cavity antenna (RCA), integrated with a frequency selective surface (FSS) radome absorber is presented. The RCA has a U-slot microstrip patch antenna (MPA) as the primary source. The cavity resonance is generated by the large ground plane and a single layer of partially reflective structure (PRS) as the superstrate, which is placed at a distance of a half-wavelength from the ground plane. The PRS consists of 12 × 12 square patch arrays. Integration with an FSS radome absorber is performed to create a high gain and low scattering functional antenna. The impact of this integration to the antenna performance is investigated. The input reflection coefficient, realized gain and radiation pattern are compared. They are relatively similar, without and with the FSS radome absorber. A slight increase in the realized gain is expected due to the contribution of the metallic FSS structure since the FSS structure is treated as the second PRS layer for the RCA in the integration.