Design of Broadband Miniaturized 5G Base Station Antenna

A broadband miniaturized dual-polarized base station antenna for 5G application is proposed in this paper. The working frequency completely covers the 5G Sub-6 GHz frequency band (3300-3600 MHz). The antenna achieves ± 45° dual-polarization by two coaxial lines for feeding and a pair of T-coupled feeding structures placed vertically. The radiation patch is composed of two bent dipoles placed orthogonally, which reduces the size of the antenna radiator effectively. In addition, the antenna uses the double-layer PCB structure and the rectangular patch on the top layer makes the antenna better matched. The relative impedance bandwidth is 53% (2.41 GHz-4.14 GHz) when the return loss is less than -10dB. The antenna gain reaches 10.1dBi at 3.45 GHz and the port isolation is greater than 23dB. Meanwhile, the cross polarization level is below -23dBi. The antenna has the advantages of miniaturization, wide bandwidth, high gain and high polarization purity.