Open AccessCompact dual‐band stepped‐impedance resonator filter with separate coupling paths
Author(s) -
Chen ChiFeng,
Chang ShengFa,
Tseng BoHao,
Weng JunHong
Publication year - 2014
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2014.2982
Subject(s) - resonator , electrical impedance , coupling (piping) , multi band device , dual (grammatical number) , filter (signal processing) , helical resonator , acoustics , physics , materials science , electronic engineering , optoelectronics , electrical engineering , engineering , antenna (radio) , metallurgy , art , literature
A new compact microstrip dual‐band bandpass filter (BPF) based on multi‐mode λ /4 stepped‐impedance resonators (SIRs) with separate coupling paths is investigated. The dual‐band BPF with a second‐order bandpass response is composed of only two λ /4 SIRs, resulting in a small circuit size. A coupling gap and a common short‐ended stub between the two coupled SIRs are used to create the electric and magnetic couplings with separate coupling paths. The bandwidths of the dual‐band BPF can be well controlled by adjusting the coupling strengths of the two coupling paths. Thus, a greater design flexibility for the dual‐band BPF can be obtained. For demonstration, a second‐order dual‐band BPF with a compact size of 0.14 λ g × 0.16 λ g has been designed and fabricated. A good agreement is achieved between simulation and measurement.