A Tomb Shaped UWB Antenna With WLAN/WiMax Band Rejection

Abstract

Ultra-Wideband is generally a technology for transmission of information scattered over a wide operating bandwidth. For decades it has been used mainly for military purposes. In the year 2002, a spectrum of 3.1 GHz - 10.6 GHz is assigned by Federal Communication Commission (FCC) to (UWB) technology for commercial use. Therefore from that time onwards UWB technology is considered as the most favourable technology for attaining high data rates, realising the dream of high speed wireless personal area network (WPAN) and providing good quality facilities to consumers. In this thesis two antennas are designed and studied. CST STUDIO SUITE is employed to create prototype of antenna and do the simulations. First a tomb shaped microstrip patch antenna is designed for UWB applications. Antenna performance depends on various parameters of the tomb shaped microstrip patch antenna. Therefore an analysis is done to see the effect of various design parameters of the antenna on the return loss. Finally the designed antenna is fabricated and experimental results are shown. A comparison between simulated and experimental results is done. As the power emission levels assigned to UWB systems by FCC are very low so they are easily interfered by neighboring communication systems. So a tomb shaped antenna having a capability to notch three bands is introduced next for use in UWB applications. Two identical L slots are inscribed in the coplanar ground to get the notched band. The notched band depends on various parameters of the L slots inscribed in ground of tomb shaped microstrip patch antenna. L slot parameters like length, width etc. are varied and return loss curves are plotted for comparing the impact of different values of the parameters. Finally the designed antenna is fabricated and experimental results are shown. A comparison between simulated and experimental results is done.