Multi-Band HTS Bandpass Filters Using Multimode Square Ring Loaded Resonators

摘要

High-temperature superconducting (HTS) filters have advantages of extreme low insertion loss and high selectivity of passbands. In this paper, three types of multi-band HTS bandpass filters (BPFs) using multimode square ring loaded resonators (SRLRs) are presented. The traditional SRLR has four resonant modes and the first one is a miniaturized quad-band HTS filter using two coupled four-mode SRLRs with ultra-low insertion losses in four passbands. Next, two stubs at two sides of SRLR are folded to a hairpin ring shape for high-order circuit design, thus a eighth-order dual-band HTS BPF using the modified SRLR is designed with high selectivity passbands. To reject common mode interference, a newly modified SRLR with shunt-ed-line structure is proposed and them a four ports dual-band HTS differential filter is developed. All these BPFs shown favorable performance.