Reconfigurable circular ring patch antenna for UWB and cognitive radio applications

In this work, a new ultra wide band circular ring patch antenna is proposed for spectral sensing application as well as the transmission and reception of radiofrequency in cognitive radio systems. The proposed structure has simple design and easy construction, making it reconfigurable by enabling or disabling the parasitic elements coplanar to the antenna. Simulation and measurements results confirm good agreement and adequate antenna response in the frequency range from 3.1 GHz to 10.6 GHz, in terms of the reflection coefficient and radiation pattern, validating the applicability of the proposed structure for cognitive radio systems front-end.