Study on a miniature UWB wafer-dipole printed antenna fed by balanced microstrip line

A novel wafer-dipole printed antenna fed by balanced microstrip line is proposed, and the adoption of the balanced microstrip line can effectively solve the feeding problem of the UWB dipole antenna. The wafer-dipole and a branch of the balanced microstrip line are printed on one side of FR-4 substrate (1 mm thickness), and the later is connected to a wafer directly, while the other branch is printed on the back side and connected to the other wafer with a via-hole. The measured results show that the antenna impedance bandwidth is from 3.0 GHz to 15.0 GHz with VSWR < 2, and the ratio bandwidth is about 5:1. Moreover, the antenna size is just 40 mm × 20 mm with simple structure, which is well suited for short-distance UWB communications.