Title :
Design of Triple-Passband Microwave Filters Using Frequency Transformations
Author :
Lee, Juseop ; Sarabandi, Kamal
Author_Institution :
Michigan Univ., Ann Arbor
Abstract :
This paper introduces a synthesis method for triple-passband microwave filters. A frequency transformation is developed for finding the locations of poles and zeros of the triple-passband filter. The poles and zeros obtained as such are optimized to achieve a transfer function with a reduced number of transmission zeros in order to reduce the number of cross-couplings. Six- and 12-pole triple-passband filters are synthesized for validation of this proposed method. A 12-pole triple-passband filter is fabricated with a microstripline structure and shown to provide good agreement between synthesis and measurement results. Finally, the frequency transformation for asymmetric triple-passband filters is briefly discussed.
Keywords :
band-pass filters; microstrip filters; microwave filters; network synthesis; poles and zeros; transfer functions; frequency transformation; microstrip line structure; poles and zeros; synthesis method; transfer function; triple-passband microwave filter; Band pass filters; Filtering theory; Frequency response; Frequency synthesizers; Microwave filters; Optimization methods; Passband; Poles and zeros; Resonator filters; Transfer functions; Circuit synthesis; microwave filters; triple-passband filters;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2007.912206