A Miniaturized Broadband Dual-Polarized Base Station Antenna

A miniaturized broadband dual-polarized base station antenna with a bandwidth of 3.4-4.0 GHz is introduced in this paper. The proposed antenna is composed of two dipoles, metal columns, feeding structures and a reflector. These two dipoles are etched on the substrate as main radiator. Gamma-shaped feeding structures are placed between the radiator and the reflect floor. The reflect floor is used to obtain unidirectional radiation. Four metal columns are introduced to extend the current path at the edge of the dipoles, which could reduce the physical size of the antenna effectively. The physical size of the antenna is 24.67 mmx24.67 mm The VSWR is lower than 1.5:1, the isolation is better than -20 dB and the antenna achieves a stable gain of 7.3 +/- 0.1 dB in the working frequency band.