A Wideband and High Gain Dual-Polarzied Antenna Design by a Frequency-Selective Surface for WLAN Application

A new dual-polarized antenna loading frequency-selective surface (FSS) is proposed for 5G wireless local networks (WLANs) application. The antenna consists of two orthogonal bow-tie dipoles and a ground plane. A new wideband FSS is designed comprising ring-slot connecting rectangular slots. The reflection coefficient of wideband FSS is less than 0.9 from 4–6.5GHz. The phase of reflection coefficient is −163◦ at 5.5GHz. The novel cell analyzed by the equivalent circuit is given and simulated. The wideband FSS is employed as a superstrate layer for bandwidth enhancement and radiation gain improvement of the antenna. After loading wideband FSS, the measured bandwidth is 5.3–6.3 GHz (17.2%) with S11 and S22 both less than −10 dB, which cover various 5G WLAN bandwidths. The gain of the antenna is 12.1 dBi at 5.5GHz. The bandwidth of antenna with FSS increases 40%, and gain improves 5.6 dBi. The simulated and measured results agree well.