A Dual-Polarized Fabry-Perot Antenna With High Isolation and Wideband RCS Reduction

In this paper, we investigates a Fabry-Perot antenna (FPA) with dual-polarization, low coupling coefficient, and wideband radar cross section (RCS) reduction. Fabry-Perot cavity is constructed by a copper-plate as ground (GND) below a single-layer partially reflecting surface (PRS). The PRS is a combination of strips array on the top side and a cross-slot array on the bottom side. While the former operates as chessboard arrangement metasurface (CAMs) to reduce RCS, the latter yields high reflection coefficient for gain enhancement. Feed antenna placed in the center of GND contains a square patch fed by 4 T-shaped feeding networks. The proposed antenna achieves a very high port-to-port isolation by remaining the symmetry structure across two planes and the support of double differential-feed. The final design with overall size of 3.2λ
0
×3.2λ
0
×0.57λ
0
at 6 GHz reaches an impedance matching bandwidth of 5.67-6.38 GHz (11.07%) for 10-dB return loss. Its 3 dB gain bandwidths are 5.63-6.29 GHz, 5.78-6.23 GHz with the highest value of 12.5 dBi, 15 dBi for port 1 and 2, respectively. Also, it achieves a wide RCS reduction bandwidth of 66.7% (4.5−9.0 GHz).