A novel broadband dual-polarized dipole antenna element for 2G/3G/LTE base stations

A novel broadband dual-polarized crossed-dipole antenna element with parasitic branches is designed for 2G/3G/LTE base stations. The proposed antenna mainly comprises a curved reflector, two crossed-dipoles, a pair of feeding strips, and two couples of balanced-unbalanced (BALUN) transformers. Compared to the traditional square-loop radiator dipole, the impedance bandwidth of the proposed antenna can be greatly improved after employing two parasitic metal stubs and two pairs of parasitic metal branches, and a better radiation performance of the proposed antenna can be obtained by optimizing the angle of the reflector. Simulation results show that the proposed antenna element can operate from 1.7 to 2.7 GHz with has an impedance bandwidth of VSWR < 1.5, the port isolation of more than 30 dB, a stable radiation pattern with half-power beamwidth 65.2°–5.6° at H-plane and V-plane, and a relatively stable dipole antenna gain of 8.5 ± 0.4 (dBi). Furthermore, measured results have a good agreement with simulated ones.