A Broadband Dual-polarized Antenna for 2G/3G/4G/5G Base Station Applications

This paper presents a novel broadband base station antenna element covering 2G/3G/4G/5G bands. The proposed antenna consists of a dual-dipole radiator and an open-box shaped reflector. The main radiating portion of each dipole arm is designed with a dual hexagon shape to improve bandwidth. Four small hexagonal-shaped parasitic patches are adopted to further decrease the reflection coefficient. Dual polarization is excited by placing two dipoles orthogonally. The open box shaped reflector derives from a planar metal plate with four inverted L-shaped edges which are arranged below the radiator to enhance the antenna gain and reduce the half power bandwidth (HPBW) in 3.3-3.8 GHz. The prototype has been fabricated and measured with bandwidth of 1.68-3.8 GHz, coupling below-20 dB, stable HPBW with 65 degrees +/- 5 degrees and average gain of 8.5 dBi. The values of the cross-polarization discrimination (XPD) are better than 20 dB at the boresight and 10 dB within +/- 60 degrees directions. The proposed antenna has a small overall size of 145x145x35.6 mm(3).