A Method for Bandwidth Enhancement of Cross-Dipole Antennas with Compact Configurations

In this paper, a new method to broaden the bandwidth of dual-polarized cross-dipole antennas is presented. By connecting a thin loop to a traditional cross-dipole, additional resonant points are introduced and the bandwidth is broadened. This method does not increase the physical dimension of the antenna and has little influence on radiation performances. A loop-connected cross-dipole antenna is presented to verify the method. The bandwidth it achieves is 66.7% from 1.65 GHz to 3.30 GHz with a very compact radiator size. The antenna also has a high port isolation level and stable radiation performances, making it highly suitable for the base station application.