Planar Structured Microwave Filters

Abstract

Electronic communication systems have changed our lives for better, by realizing and adopting newlinewireless communication systems, such as GSM, WLAN, WiFi, UWB, Bluetooth and others. newlineMicrowave filter forms one among the building blocks of the communication equipment and has newlineseen a tremendous development as the communication industry progressed. There is a huge newlinerequirement of more filters with high performance, small size, compact, robust and at different newlinecentre frequencies for ground and space based systems in ISRO, DRDO, CSIR etc. Microwave newlinefilters possessing various forms are essential components in radar, satellite and mobile newlinecommunication systems. Increased demand for low loss, miniature filters, that can be mass newlineproduced at low cost, have provided a significant challenge, reinforcing the need for improving newlineor even replacing the conventional filters. newlineThis thesis investigates and proposes novel planar filter structures, employing folded hairpin newlineresonators. Such filters are not only compact, but also can improve the RF performance in both newlinepassband and stopband. To verify the concept and validate of the developed folded filters, both newlinetheoretical and experimental results are presented and their performance was compared. The newlineexperimental results confirm the validity the theoretical design of the proposed filters designed newlineat various centre frequencies covering L and S band, which makes this concept very attractive newlinefor applications in in mobile, airborne, satellite deep space communications. newlineMiniaturization of electronic components has received a lot of attention in the last few decades newlinedue to the rapid development and deployment in the telecommunication industry. Traditional newlinehigh performance waveguide and dielectric resonator filters are usually too heavy and bulky for newlinemost of the applications in the field of microwaves. New techniques and solutions for designing, newlinecompact and small sized folded micro strip resonator filters have been found in the literature and newlineare further explored in this thesis, to improve the ...