Study On Simulation, Designs And Experiments Of UWB Antennas

Bandwidth allocation to ultra wide band applications has introduced dramatic increase in the research area of antenna design. High data rates, low probability of detection, immune to multipath interference and simplicity are the most prominent features of ultra wide band (UWB). The design considerations for UWB antenna include impedance matching, impedance bandwidth, radiation characteristics, size, type and channeling. Both the printed and planar monopole antennas are studied in the present thesis. However, the focus of this thesis is to design highly efficient UWB antenna with low VSWR. The study also includes the consideration for size reduction and omni-directional coverage. The bandwidth is improved beyond the current standards to meet the requirements of next generation UWB systems. Due to the interference of UWB with already employed commercial terrestrial systems, the band notching is also considered in one of the proposed designs. The wind loading affect for the base station outdoor antenna is accounted as a major problem and the effect is severe for low frequency antenna designs. For such applications, some fractal or self-similar geometries based on Descartes Circle Theorem are optimized for UWB antennas by overcoming the natural problem of junction points of these designs.