Improving Front-to-Back Ratio of Base Station Antenna Array With a Modified Reflector

An antenna array with a high front-to-back ratio (FBR) permits low interference for other arrays in the backward region. In this paper, a modified reflector is designed for improving the FBR of a dual-polarized cross-dipole linear base station antenna array. The stair-shaped baffles on the edges of the reflector are used to suppress the backward diffraction field. To further improve FBR, arrow-shaped periodic units are cut on the reflector which uses the transmission field to cancel the backward radiated field. The simulated results show a 13–18 dB improvement of the FBR across the frequency band 690–960 MHz and the antenna array maintains a stable radiation performance and compact size.