Unidirectional planar monopole ultra-wideband antenna using wrench-shaped feeding structure

摘要

A unidirectional planar monopole ultra-wideband (UWB) antenna is presented. To realise unidirectional radiation, a new feed structure is implemented without modifications in the ground plane or the monopole. By using a wrench-shaped feeding structure, unidirectional radiation of the planar monopole antenna can be realised, especially at high frequencies. The antenna is built on a 20 × 30 mm FR4 substrate to cover a frequency bandwidth from 3.1 to over 14 GHz for a voltage standing wave ratio ≤2.