An Extremely Low-profile Dual-band Antenna Based on Miniaturized Metasurface for 5G Mobile Applications

In this paper, we propose a dual-band metasurface (MTS)-based antenna with an extremely low-profile for 5G mobile applications. The MTS is miniaturized and suitable to be placed on the back cover of the mobile phone. Compared with the conventional patch-based MTS, the area of the proposed one has decreased by 61.7%. With an extremely low-profile of 0.008
$\lambda_{0} (>\lambda_{0}$
is the vacuum wavelength at 3.5 GHz), the proposed antenna can partially cover two 5G bands of N78 (7.9%, 3.37-3.65 GHz) and N79 (5.3%, 4.77-5.03 GHz) The lower band is produced by the feeding-slot on the ground layer, while the upper band is mainly generated by MTS. The MTS-based antenna is also suitable to be expanded into a 4 × 4 MIMO system without additional space. The simulated results show that the isolations among the ports are all above 20 dB in the two operating bands.