A Low Profile Dual Band Dual-Polarization Shared-Aperture Base Station Antenna

A low profile shared-aperture base station antenna with dual-band and dual-polarization characteristics is proposed. The proposed antenna is mainly composed of four parts: a lower-band element, a upper-band element, a feeding substrate, and a reflector with four baffles. The lower-band element adopts a slotted square ring path excited by four v-shaped feeding probes, while the upper-band element adopts a pair of planar printed dipoles. The hollow structure in the lower-band element provides a extra space for the upper band antenna. The simulated and measured results show that the proposed shared-aperture antenna covers the frequency bands from 1.71-2.1 GHz and 3.3-3.8GHz with a high isolation between its ports. The simulation gain is above 6dBi and 9dBi for lower and upper band, respectively.