A low-profile dual-band dual-polarized tightly spaced antenna array with artificial magnetic conductor surface for 5G micro base station application

A novel low-profile dual-band dual-polarized tightly spaced antenna array with artificial magnetic conductor (AMC) surface for 5G micro base station application is proposed in this paper. The main radiating element is a pair of crossed annular dipoles, excited with two different resonant modes in orthogonal arms. The radiator is backed by an additional dual-band AMC reflector located 0.03 lambda(0) below. Four such elements are then tightly spaced to form an antenna array. By replacing the four interior AMC patches with an S-shaped patch, the strong coupling at the lower band is successfully mitigated. The final results show that the dual-band array has an impedance bandwidth of 13.8% (2.44-2.80 GHz) and 6% (4.75-5.03 GHz), covering the sub-6GHz band of China Mobile. The antenna's peak realized gain is 10 dBi at the lower band and 13.7 dBi at the upper band, making it a good candidate for 5G micro base stations.