Design of a Novel Ultrawideband Wire Antenna With Enhanced Bandwidth

In this letter, a novel ultrawideband wire antenna with enhanced bandwidth is presented. The proposed antenna consists of a dipole structure, and each pole is formed by connecting four semicircular closed wires. A sphere crown and several rods are introduced to improve the impedance match during an ultrawide band. Experimental results show that the antenna achieves good impedance match from 0.45 to 28.4 GHz with the voltage standing wave ratio (VSWR) less than 2 while maintaining omnidirectional radiation pattern. The parameters that affect the impedance match of the antenna are also investigated. The proposed wire antenna is highly suitable for applications of wideband systems.