Open AccessQuad‐band bandpass filter based on single stepped‐impedance ring resonator
Author(s) -
Xiao Mi,
Li Xiaozheng,
Sun Guoliang
Publication year - 2016
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
eISSN - 1350-911X
pISSN - 0013-5194
DOI - 10.1049/el.2016.0245
Subject(s) - passband , band pass filter , resonator , helical resonator , electrical impedance , acoustics , electronic engineering , physics , transmission (telecommunications) , filter (signal processing) , split ring resonator , optoelectronics , optics , computer science , electrical engineering , engineering , telecommunications , quantum mechanics
A novel compact quad‐band bandpass filter (BPF) using a single stepped‐impedance ring loaded resonator (SIRLR) is introduced. Different from other multi‐mode resonators proposed recently, the SIRLR generates two transmission poles (TPs) on each passband of the BPF so that a quad‐band BPF can be realised using only one resonator. Due to the multipath structure, three transmission zeros (TZs) are created between passbands, resulting in the improvement of band‐to‐band isolation. TPs and TZs are carefully controlled and adjusted by tuning electric length and impedance of the SIRLR to satisfy the demands of proposed quad‐band BPF. The proposed filter was fabricated and just occupied 0.18 λ g × 0.15 λ g . The results of simulations and measurements agree very well.