Compact superconducting single-and dual-band filter design using multimode stepped-impedance resonator

摘要

This study presents two multimode stepped-impedance structures to design single-and dual-band filters.Transmission zeroes are introduced for the single-band filter by using dual-mode stepped-impedance resonators.The single-band filter with high selectivity is centered at 6.02 GHz and has a fractional bandwidth (FBW) of 25.6％.Four stubs (two low frequency and two high frequency ones) are connected to the rectangular patch in the center to construct a quadruplemode resonator.The independent conditions of the center frequencies of the high and low bands of the resonator are analyzed.A dual-band filter,which operates at 1.53 GHz and 2.44 GHz with FWBs of 12.1％ and 14.1％,respectively is designed.The single-and dual-band filters are both fabricated with double-sided YBCO films and they can be used in mobile and satellite communications.