Design of Antennas with Enhanced Gain Bandwidth and Reconfigurability

Abstract

In recent years, a tremendous growth has been observed in wireless products/services newlinewhich demand seamless integration with such sub-systems which operate on standards newlinelike GSM, CDMA, ISM, WLAN, UWB etc. Design of front end of these wireless newlinecommunication systems poses challenges due to the major issues like high data rate newlinecapacity, multiband/wideband operation with reasonably good gain, high signal to noise newlineratio (SNR) and so on. For the overall communication system to be able to provide these newlinefeatures apart from the other blocks the antenna should also be able to match the overall newlinetransceiver system performance. The key performance parameters of antenna include its newlinegain, operating bandwidth and its ability to reconfigure its pattern/operating frequency. newlineThe present research work is focused on design of microstrip antennas to: newline1. achieve Gain enhancement newline2. achieve wideband/UWB operation newline3. achieve frequency and pattern Reconfigurability newlineIn this work microstrip antenna of different shapes and substrate materials are taken for newlineenhancement of the above mentioned performances with different feed types. The newlinestandard simulation tools used in industry/academia are used for the design and newlineoptimization of antenna parameters. The simulated results are validated either by newlinesimulation using tool based on any other method or by measured results. newlineThe key challenge in design of wideband/multiband antenna is to maintain stable newlineradiation characteristics throughout the operating band. In the current work the antennas newlinedesigned to achieve wideband/multiband operations satisfy this performance newlinecharacteristic. newlineThe major design issue associated with the frequency and pattern reconfigurable antennas newlineare their radiation pattern and frequency of operation respectively under various modes of newlineoperation. The designed reconfigurable antennas presented in the thesis satisfy these newlinerequirements. newlineii newlineFor the design of UWB antennas which transmits narrow pulses with minimum distortion the key challenge is not only to design a broad band antenna wi