Compact sext‐band bandpass filter based on single multimode resonator with high band‐to‐band isolations. Issue 9 (4th April 2016)

• Record Type: Journal Article
• Authors: Ai, Jing; Zhang, Yonghong; Xu, Kai Da; Guo, Yingjiang; Joines, William Thomas; Liu, Qing Huo
• Is Part Of: Electronics letters. Volume 52:Issue 9(2016)
• Page Start: 729
• Page End: 731
• Publication Date: 2016-04-04
• Subjects: resonator filters -- band‐pass filters -- microstrip filters -- microstrip lines -- poles and zeros; single multimode resonator -- high band‐to‐band isolations -- MMR -- miniaturised microstrip sext‐band bandpass filter -- BPF -- SIR -- band‐to‐band isolations -- identical open‐circuited stubs -- transmission poles -- transmission zeros -- electrical lengths -- input‐output tapped branches -- radical stub‐loaded short‐circuited lines -- perturbation structures; Electronics -- Periodicals; 621.381
• DOI: 10.1049/el.2016.0227
• Languages: English
• ISSNs: 0013-5194

Abstract

Abstract : On the basis of a single multimode resonator (MMR), a miniaturised microstrip sext‐band bandpass filter (BPF) with high band‐to‐band isolations has been presented. The proposed MMR is an stepped impedance resonator (SIR) with one short‐circuited stub loaded in the middle and two identical open‐circuited stubs located at two sides. Transmission poles (TPs) and transmission zeros (TZs) can be excited when the electrical lengths of two open stubs increase. The TZs introduced by open stubs separate the TPs into multiple groups; therefore, the design of a sext‐band BPF becomes available. Moreover, two input/output tapped branches and radical stub‐loaded short‐circuited lines are treated as perturbation structures in order to increase design freedoms for improving filter performance. Good agreement between simulated and measured results validates the design method.