Selectivity Increasing of Resonator on Open-Circuited Stubs

Abstract

The features of the frequency impedance characteristic, as well as the transmission response of a resonator based on two open-circuited stubs, are considered. The advantage of such a resonator is the high steep slope of the frequency response and the presence of two zeros near the resonant frequency. A noticeable selectivity deterioration in the stop bands when detuning from the resonant frequency of a resonator limits its use. Solutions on the basis of transmission line sections, allowing to improve the suppression in the stop-bands and increase the quality factor of such resonator, are proposed and analyzed.