Design of an Improved Miniaturized Ultra-wideband Antenna

This paper presents an improved ultra-wideband antenna design. The proposed antenna has with the characteristics of miniaturization and ultra-wideband. The proposed antenna is composed of the microstrip feed line, the dielectric substrate, and a modified ground plane with an exponential function gradation line. The size of the antenna can be reduced by half on the basis of the original antenna through introducing a mirror metal plane to achieve a miniaturized design without affecting the performance. By etching the L-shaped slot on the ground plane, the bandwidth of the antenna can also be increased. The improved antenna has good radiation characteristics with a stably directional radiation pattern in the whole working bandwidth.