Improvement of Characteristics of Dielectric Circular Resonator and Its Filter Application

The improvements of a circular waveguide-type resonator for gaining better characteristics, i.e. higher Q value and bigger separation of higher-modes, are investigated. The resonator which is fabricated by lamination of metal strips in sectorial segmentations etched on a teflon board is intended to excite a TE
_11delta
mode selectively. The resonant frequency and unloaded Q of dielectric circular resonators in which the gap between metal strips and the number of metal strip are changed are analyzed by use of an HFSSreg simulation, and then the results are compared with the experimental ones. To demonstrate the feasibility of improvement, a 2-stage bandpass filter encapsulated in a metal circular waveguide is realized