Novel single-band and multi-band bandstop filters for modern wireless communication systems
Date
2016-04-29
Authors
Esmaeili, Mahbubeh
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The objective of this thesis is to introduce novel procedures and guidelines to design
bandstop microwave filters for modern terrestrial and satellite wireless communication
systems. Among all available microwave filter technologies, planar structures
of microstrip and substrate integrated waveguide (SIW) are chosen, due to ease of
fabrication, low profile, weight and manufacturing cost. Particularly, SIW structures
are more attractive because they have a better insertion loss, quality factor, and
power handling capability in comparison to their microstrip counterparts, and can
also be easily integrated into other planar circuitries.
A comprehensive hybrid analytic-optimization method is developed to synthesize
any single-band as well as multi-band bandstop coupling matrix. In this method, the
location of reflection zeros (RZs) and the attenuations in stopbands can be determined
in advance.
Several novel single-band, dual-band, and triple-band bandstop filters are designed
using regular and ridged SIW resonators, in-line coupled singlet resonators,
cross-coupled resonators, and bandstop stubs. The designed filters have fractional
bandwidths up to 23% . Moreover, a tunable ridged SIW bandstop resonator and a
tunable CPW resonator, etched into the top plate of the SIW transmission line, are introduced. Combining these two resonators, a dual-band SIW filter is designed that
permits one of its stopband to be tuned while another stopband is fixed.
All introduced filters in this thesis are verified by commercial electromagnetic
software, analytic investigations using Matlab codes, and measurements.
Description
Keywords
Microwave filters, Multi-band bandstop filters, Single-band bandstop filters, Non-resonating mode, Cross-coupled resonator filters, Substrate integrated waveguide