Wide band dual-polarized antenna array of planar dipoles for base stations of mobile communication

Abstract

A novel wideband modification of the base station antennas for mobile communication based on crossed planar dipoles is proposed for operation within frequency band 1.4-2.7 GHz. The operational frequency band of the suggested design of crossed dipoles was extended due to optimization of the profile of dipole arms approximated by means of Bezier curves of third order. The fine tuning of the mutual coupling of the crossed dipoles is achieved by optimization of the arms profile which yields the extension of the frequency band with high impedance matching and port isolation of antenna. The Bezier curves parameters were used as the optimization parameters. The characteristics of single antenna as well as 8-element array of crossed dipoles are studied in detail. The obtained characteristics of antenna array meet to the main requirements for base station antennas. Reflection coefficient within operational frequency band about octave is less than -14…-15 dB, ports isolation is -25 dB, cross polarization component is less than -17.5 dB. The antenna has the stable radiation pattern within operational frequency band the beam width for the level -10 dB in horizontal plane is equal to 120°+18°/-7°.