Compact ultra-wideband bandpass filters with narrow notched bands based on a ring resonator

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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  • Wenjie Feng
  • Wenquan Che
  • Quan Xue


Original languageEnglish
Pages (from-to)961-969
Journal / PublicationIET Microwaves, Antennas and Propagation
Issue number12
Publication statusPublished - 2013


In this study, compact ultra-wideband (UWB) bandpass filters with single/dual-notched bands are proposed based on a ring resonator and transversal signal-interference concept. Broad passband and narrow notched bands with controlled even/oddmode resonator frequencies can be adjusted conveniently by changing the characteristic impedance of the ring resonator. Transmission zeros are introduced to improve selectivity and harmonic suppression of the proposed UWB bandpass filters with notched bands. To verify the presented strategies, three prototypes (er = 2.65, h = 0.5 mm) with 3 dB fractional bandwidth >120% are designed and fabricated. Simple structure and good in/out-of-band performances can be achieved in the proposed UWB bandpass filters. © The Institution of Engineering and Technology 2013.