Design of a microstrip-fed ultra-wideband monopole antenna having band rejection characteristic

A new compact and microstrip-fed ultra-wideband (UWB) monopole antenna having band rejection characteristic is proposed. By using tuning stub and stepped ground, the antenna provides an enhanced impedance bandwidth. The band stop characteristic is realized using an inverted-U shaped slot. The range of stop band can be adjusted by changing the length and width of the inserted slot. The measured impedance bandwidth of the proposed antenna ranges from 2.9 GHz to 12.1 GHz for VSWR < 2 while having the band rejection characteristic in the frequency band of 4.9 GHz to 6 GHz. This antenna shows a monopole-like radiation pattern and flat gain characteristic throughout the operating frequency band.