Abstract
A novel modified printed monopole antenna with variable frequency band-notch characteristic for ultra-wideband (UWB) applications is presented. The proposed antenna consists of a truncated ground plane and a radiating patch with two tapered steps. To generate a notch band at 5-6GHz with good level of band-notch a new T-shaped parasitic element placed on the back layer of the substrate along with a simple circular slot etched on the patch is implemented. The proposed antenna has a compact size of 14 × 20mm2, a measured impedance bandwidth of 3.05 to 14.7GHz for VSWR < 2 and exhibits an omni-directional H-plane radiation pattern throughout the UWB frequency range.