A novel high-isolation, dual-polarization broadband array antenna with low cross-polarization for 3G base station

In this paper, a novel linear array antenna is proposed and investigated experimentally and the measured results are plotted. The measured impedance bandwidth determined by VSWR≪1.5 covers 1710∼2170MHz and the port isolation is better than −30dB by additive isolated conducting frames which change the other array characters very little. The cutting slots in the side walls of the ground provide the given HPBW of 90±8°(Half-Power Beam Width) in azimuth plane and maintain a stable array characters. The antenna has a high front-to-back ratio of radiation pattern of 25dB and a low cross polarization level (−10dB in the forward region and −22dB on the axes of peak gain). The array formed by printed microstrip antennas mainly features in the slots and the isolated conducting frames which ensure the array characters satisfy the wireless communication criterions. The array antenna is highly suitable for the base station applications for 3G system.