Institute of Research and Journals (IRAJ)
In this paper, the authors present an antenna scheme suitable for cognitive radio applications. The Omni-directional c-shaped monopole disc antenna is designed to achieve impedance matching for ultra-wide band range. The proposed antenna uses FR-4 substrate having thickness of 1.6mm and dielectric constant 4.4. The antenna achieves an enhanced impedance bandwidth of 121.36% covering from 4.666 to 12GHz with a stable radiation performance and omnidirectional radiation pattern. The radiated patch occupied a total volume of 50x60x1.6mm.