Engineering Designs of Dual-Polarized Antennas With Reduced Profile and Mutual Coupling for 5G Microcell Application

In this letter, a miniaturized, low profile and low mutual coupling antenna array with stable radiation pattern for fifth-generation microcell is presented. The antenna element contains three parts, folded dipole radiator, vertical feeding baluns, and reflector. Four striplines with end connections and stepped slots etched on the main radiator are adopted to enhance the impedance bandwidth and miniaturized the antenna's aperture in the low-profile configuration. While folded stripline structure is applied to reduce the mutual coupling in dual-polarized antenna. The height of proposed antenna is only 0.1 λ
₀
(λ
₀
is the free-space wavelength referring to the center operation frequency) and the antenna's aperture is only 0.4 λ
₀
× 0.4 λ
₀
. Measured results show that the antenna array has good performances, exhibiting low voltage standing-wave ratio (VSWR < 1.5), high isolation (> 30 dB), and wide bandwidth (3.2–3.9 GHz, 20%). Stable radiation patterns are measured across the operating bandwidth.