A High-Gain Wideband Fabry-Pérot Antenna Employing a Water-Based Frequency Selective Surface for Polarization- and RCS-Reconfigurability

A Fabry-Pérot (FP) antenna with wideband dual-polarization and radar cross section- (RCS-) reconfigurability adopting water-based frequency selective surface (FSS) is presented. The feed antenna is designed to switch between horizontal polarization (HP) and vertical polarization (VP) by controlling the on/off states of two PIN diodes. By optimizing the height of the FP resonant cavity, the proposed FP antenna achieves wideband and high-gain properties. In addition, the incident wave can be absorbed when the polymethyl methacrylate (PMMA) container is filled with water, which reduces the monostatic RCS. This design can be selected to be in stealth mode or radiation mode by injecting water into or extracting water from the water container. The measured results indicate that in stealth mode, the 10-dB RCS reduction band is from 4.5 GHz to 6.4 GHz, and the peak RCS reduction is 31.5 dB at 5.2 GHz. In the radiation mode, the realized gains of the FP antenna in both HP and VP at 5.2 GHz reach 16.6 dBi. Simulated and measured results verify the realizability and operational concept of the designed FP antenna.