A Low-Profile Wideband Hybrid Metasurface Antenna Array for 5G and WiFi Systems

A hybrid metasurface (HMS) is proposed to form a low-profile wideband antenna array. The antenna element is an array of 4 × 4 square metal patches and fed by a 50 Ω microstrip line through an H-shaped coupling slot on the ground plane. Only are the edge patches of HMS antenna element grounded by shorting pins for the suppression of surface waves and crosspolarization levels as well as the enhancement of the gain. With the HMS antenna element, a compact 2 χ 2 array with an overall size of 1.58λ 0 × 1.58λ 0 ×0.068λ 0 (λ4 is the free-space wavelength at 5.0 GHz) is designed, where the adjacent elements share the edge patches of the elements. The measurement shows the impedance bandwidth of 28% (4.41-5.85 GHz) for |S 11 | ≤ -10 dB is obtained, and the boresight gain is greater than 8.4 dBi across the operating band, covering both fifth-generation (5G) sub 6 GHz and WiFi bands.