Notch Reconfigurable UWB Antenna Design

Abstract

The goal of this thesis is to first design a UWB circular antenna with single and dual notch band characteristics. Second goal of the research work is to design frequency reconfigurable antenna and understand the importance of multifunctional antennas due to the uplifting demand of high transmission rate and advance wireless communication. Reconfigurable antenna is designed by combining filters and antenna which are called filtennas. In this thesis we have designed a circular patch UWB antenna and further modified this antenna by placing two symmetrical resonators E and C shaped beside feedline to attain band notch characteristics. This technique is placing parasitic elements near the radiating patch for achieving band notch characteristics. After obtaining a notch band UWB antenna, a frequency reconfigurable antenna is designed. Reconfigurability is achieved by employing RF switch in correct location which connects two parasitic elements and reconfigures one shape into another that is reconfigures E shape to C shape or vice-versa. One single frequency reconfigurable antenna has two antenna characteristics. One antenna that is configured has capability to reject interferences from WLAN, WiMAX and C band spectrum. Second antenna is reconfigured when resonator shape changes to E shape from C shape and it has capability to reject interferences from WLAN, WiMAX, C band spectrum and X band satellite communication. The simulated and measured results have good agreement and measured radiation pattern represent that proposed antenna has omnidirectional characteristics in the H plane. Gain varies between 2 to 5.5 dB at different operating frequencies and is good for practical application. Practical applications require many services which reconfigurable antennas can generate and it can easily be integrated in portable devices. The proposed frequency reconfigurable antenna is simulated using CST Studio Suite Software.