Various λ/4 resonators with improved resonance responses and their applications to BPFs for improving out-of-band characteristics

摘要

In this paper, improvement of resonance responses is carried out by the operation of the former proposed λ/4 resonator and the tapped λ/4 resonator. A new loaded-element tapped λ/4 resonator is also proposed and its resonance responses are examined. Moreover, various bandpass filters (BPFs) based on mixed λ/4 resonators are proposed. As a result, It has been verified that the skirt characteristics and the spurious responses of the λ/4 resonator BPFs are achieved on the basis of our proposal.