Lam, Hung-Jui2007-12-222007-12-2220072007-12-22http://hdl.handle.net/1828/288Ultra-wideband (UWB) antennas are one of the most important elements for UWB systems. With the release of the 3.1 - 10.6 GHz band, applications for short-range and high-bandwidth handheld devices are primary research areas in UWB systems. Therefore, the realization of UWB antennas in printed-circuit technologies within relatively small substrate areas is of primary importance. This thesis focuses on the design of a new UWB antenna based on coplanar technology. Compared with microstrip circuitry, coplanar technology achieves easier fabrication and wider antenna bandwidth. Two professional full-wave field solver software packages, HFSS and MEFiSTo-3D, are used as analysis tools to obtain antenna performances. A new printed-circuit antenna in coplanar technology for UWB systems is introduced. The frequency of operation is 3.1 GHz to 10.6 GHz with a VSWR < 2. Nearly omni-directional characteristics in vertical polarization are demonstrated at selected frequencies. Relatively good group delay characteristics are obtained and compare well with other published UWB antenna designs.enAvailable to the World Wide WebUltra-Wideband AntennaCoplanar TechnologyUWBUVic Subject Index::Sciences and Engineering::Engineering::Electrical engineeringThesis