A Novel Compact Reconfigurable UWB Antenna for Cognitive Radio Applications

In this paper, a novel reconfigurable antenna covering a 10: 1 bandwidth is designed and fabricated for cognitive radio applications. The proposed novel antenna covers 400 MHz to 4 GHz frequency range, while keeping its size suitable for potential MIMO applications. The wide frequency configuration is obtained by combining ultra-wideband (UWB) monopole configuration together with tunable matching network via two different signal paths from the feed point. The first path is directly connected to the UWB antenna, which covers 1-4 GHz operation frequency range. The second path, for frequency range between 400 MHz and 1 GHz, goes through a tunable matching network, which matches the UWB antenna. Two discrete switches are used to toggle between the lower and higher operating bands. Simulated and measured results are presented.