Tunable Band-Notched High Selective UWB Filtering Monopole Antenna

This communication presents the design, fabrication, and testing of a tunable band-notched UWB filtering antenna. The proposed filtering antenna comprises a semiellipsoid radiator and a microstrip transmission line to cover the UWB communication bandwidth from 3.1 to 10.6 GHz. It also comprises two J-shaped open-ended stubs and an asymmetric T-shaped open-ended stub to create notch bands at 3.5 GHz (WiMAX), 5.2 GHz, and 5.8 GHz (WLAN) in the UWB spectrum. The center frequencies of the notch band are tuned continuously using varactors with percentage tuning of 7.5%, 5.38%, and 3.54%. The prototype is fabricated and experimentally validated.