Triple-layer Complementary FSS for the Mutual Coupling Reduction of Relay Antenna Arrays

A novel triple-layer complementary frequency selective surface (FSS) for the mutual coupling reduction of relay antenna arrays is proposed in this paper. The relay antenna arrays include a 2 × 4 antenna array (the backhaul antenna) and a 1 × 2 antenna array (the access antenna). Four sets of triple-layer complementary frequency selective surface and the metal reflector form a cavity for the backhaul antenna. Simulated results show that the port isolation with the same polarization and the cross polarization can be improved at most 2.7 dB and 7.2dB over the frequency band of 2.5—2.7 GHz, respectively. More importantly, the backhaul antenna still keeps good performance with VSWR<1.5 and stable radiation pattern, while the FSS-based cavity is loaded.