Investigation of dual-polarized ultra-wideband antenna with directional patterns

摘要

The design and study of multi-port single and dual-polarized ultra-wideband (UWB) antennas has been investigated in this paper. Each UWB element consists of a slotted ground plane which is fed by a L-shaped stepped microstrip line to achieve a wide bandwidth. A dumbbell-shaped slot is embedded in the ground plane to improve the impedance matching across the wide frequency range. To achieve dual orthogonal polarizations, a dual-element structure has been employed by rotating one element 90 degrees. Moreover, the four-port dual-polarized UWB antenna has been obtained by adding another two elements which enables symmetrical radiation patterns. A compact cavity has been utilized to reduce the backward radiation and enhance the front-to-back ratio (FBR). The results have confirmed that, the obtained antennas can achieve a wide frequency band from 3 to over 10 GHz.