Abstract
A two-element array antenna using rectangle patch elements for UWB application is proposed. A novel Marchand balun is chosen as the feeding structure. This balun excites signals of Equi-amplitude and 180 degree phase difference. The radiation pattern of the antenna is omnidirectional at H-plane and bidirectional at E-plane. The measured VSWR is less than 2 over the frequency bandwidth (3–11 GHz). The simulated gain is 2.8–8.49 dB, especially increased at higher frequencies because of the array factor effect. The measured results are in good agreement with the simulated results.