DESIGN OF MODIFIED GROUND SQUARE-SHAPED FRACTAL ANTENNA FOR UWB APPLICATIONS

摘要

This article presents the design of modified ground square-shaped fractal antenna. The prototype antenna is designed and fabricated on FR4 substrate of dielectric constant ε_r = 4.3 and thickness h = 1.53 mm. The proposed antenna is excited using coplanar waveguide feed. The experimental result of square-shaped fractal antenna exhibits the excellent ultra-wideband (UWB) characteristic corresponding to impedance bandwidth of 148.13% from 2.235 to 15.0 GHz, exceeding Federal Communication Commission (FCC) frequency range with a return-loss performance S_(11) = -10 dB. The simulated results are in good agreement with the experimental results. The experimental radiation patterns of this square-shaped fractal antenna are omni-directional in H-plane and bidirectional in E-plane. This proposed antenna can be useful for UWB system, microwave imaging and vehicular radar.