Design and Synthesis Techniques for Reconfigurable Microwave Filters using Single and Dual-Mode Resonators

Abstract

This thesis discusses the investigation and development of design methodologies for the creation of multifunctional band-pass filters capable of tuning to different frequency bands as well as varying their fractional bandwidth. This research also studies polynomial synthesis procedures as a tool for the derivation of reconfigurable planar filters with advanced asymmetrical responses.

The work presented here relates to the evolving multifunction philosophy of RF systems. This analysis presents a comprehensive study of microwave resonators, which generate reliable and scalable filter topologies with tunable properties. The study includes the analysis of single, dual and triple-mode filters together with an investigation of the coupling behavior of synchronously and asynchronously tuned resonators. This study identified the main properties responsible for frequency and bandwidth control in a filter, and consequently systematically created innovative design techniques.

The research also deals with the development of synthesis procedures for filters with advanced asymmetrical responses. The main goal of this effort is the creation of planar reconfigurable filters with arbitrary assigned transmission zeros. These advanced realizations requite meeting complex design specifications of advanced systems in both commercial and military applications. This work involves an in-depth investigation of polynomial synthesis methods for filters with crossed-coupled resonators and fully canonical form realizations using topologies with source and load coupling.