Small modified monopole antenna for ultra-wideband application with desired frequency band-notch function

A novel printed monopole antenna for ultra-wideband applications with a frequency band-notch characteristic is presented. The proposed antenna consists of a stepped rectangular radiating patch and a modified ground plane that provides a wide usable fractional bandwidth of more than 120% (2.75-12.8 GHz). By cutting two rectangular slots with variable dimensions on the radiating patch, frequency band-stop performance is generated and we can control its characteristics such as band-notch frequency and bandwidth. The designed antenna has a small size of 12 × 20mm² while showing band rejection performance in the frequency band of 5.05-5.98-GHz.