An Improved Impedance Bandwidth of Modified UWB Antenna With Staircased Parasitic Rings

In this letter, a structural modification technique of simple monopole to improve the input impedance bandwidth by using multiple staircased parasitic rings is suggested. In addition, the shape and size of parasitic rings are optimized to enhance the antenna bandwidth. The final optimized parameter values have been obtained from the parametric studies of the antenna and simple equation evaluating the resonant frequency. The electrical performances of the proposed antenna are verified in terms of the return loss and the radiation pattern by using commercially available softwares, CST MW Studio, and HFSS based on FDTD and FEM algorithms, respectively.