A novel ultrawideband planer antenna design with tunable band-notch characteristics

In this paper, a novel Ultrawideband (UWB) planer antenna with tunable band-notch characteristics is proposed. By changing the bias voltage applied to the varactors, the band-notch frequency center could be easily adjusted accordingly. The simulation results indicate that, when the effective capacitance of the varactor changed from 1 pF to 0.1 p F, the frequency center can be shifted from 3.32 GHz to 4.68 GHz, exhibiting 34% tunable fractional bandwidth. Moreover, the radiation performance, which includes gains, radiation efficiencies and radiation patterns, at other frequency points within UWB band did not degrade according to our simulation study.