Low-Profile Metasurface-Inspired Dual-Polarized Cavity Antenna for 5G NR Applications

A low-profile, cavity-backed, dual-polarized antenna inspired by metasurface for 5G new radio (NR) applications is proposed. Equivalent circuit model is extracted to elaborate its working principle. Owing to the square-slotted metasurface, good miniaturization and an enhanced aperture radiation efficiency are achieved simultaneously. Two orthogonal slot coupled feeding lines are used to excite the two polarization modes with high isolation. The proposed antenna has a low profile of 0.05 λ₀ (where λ₀ is the free space wavelength at 3.2 GHz). The measured results of the antenna prototype show that a -10 dB |S₁₁| bandwidth from 3.18 to 4.16 GHz (27.6 %) is achieved, which completely covers the 5G N78 band (3.3-3.8 GHz). The measured peak gain and radiation efficiency are greater than 5.20 dB and 84 %, respectively. This antenna is very suitable for 5G-NR micro base station applications.