Small monopole antenna with multiresonance characteristic by using rotated T‐shaped slit and parasitic structure for UWB systems

In this letter, we present a new design of small‐sized, low‐profile, and multiresonance monopole antenna for ultrawideband applications.The proposed antenna consists of a square radiating patch and a ground plane with rotated T‐shaped slit and conductor‐backed plane, which provides a wide usable fractional bandwidth of more than 130% (3.05–15.27 GHz). By cutting a rotated T‐shaped slit on the ground plane and also by inserting rotated T‐shaped parasitic structure, additional resonances are excited and hence much wider impedance bandwidth can be produced, especially at the higher band. The designed antenna has a small size. Simulated and experimental results obtained for the proposed antenna is suitable for UWB applications.