Reconfigurable slot antenna for Cognitive Radio applications

This paper presents a printed antenna having a reconfigurable impedance bandwidth. The bandwidth can be switched between any one of three discrete states. In the first two states the antenna yields a UWB response ranging from 8.14GHz and 2.55GHz, respectively, to a frequency in excess of 11 GHz. In the final operating state the antenna yields narrowband performance at 4.3GHz and 10.3GHz. In order to reconfigure between these three different modes one requires 8 microwave switches. The design is fairly simple in construction, importantly it is also uniplanar.