Open AccessCompact wide‐stopband SIW dual‐band filter with closely spaced passbands
Author(s) -
Xie HaoWei,
Zhou Kang,
Zhou ChunXia,
Wu Wen
Publication year - 2020
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.2020.0804
Subject(s) - stopband , passband , offset (computer science) , band pass filter , transition band , coupling (piping) , physics , filter (signal processing) , materials science , electronic engineering , optoelectronics , acoustics , optics , engineering , computer science , prototype filter , low pass filter , electrical engineering , metallurgy , programming language
Compact substrate‐integrated waveguide (SIW) dual‐band bandpass filter with closely spaced passbands and wide‐stopband characteristics is proposed for the first time based on inline‐coupled perturbed SIW triple‐mode cavities. The first three resonant modes in the triple‐mode cavities can be flexibly controlled so that two closely spaced passbands can be realised based on the first two resonant modes, and wide‐stopband can be achieved by staggering the third and other higher‐order resonant modes without resorting to extra structures. The external and internal couplings of the dual passbands can be specified and designed flexibly benefitting from the offset feeding ports and coupling windows. A prototype centred at 13 and 14 GHz is synthesised, designed, fabricated, and tested as a demonstration, extending the stopband to 1.97 f 1 with rejection level better than 25 dB.