Open AccessBandpass filters with multiple transmission zeros using open/shorted stubs
Author(s) -
Feng Wenjie,
Gao Xin,
Che Wenquan
Publication year - 2015
Publication title -
iet microwaves, antennas and propagation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.555
H-Index - 69
eISSN - 1751-8733
pISSN - 1751-8725
DOI - 10.1049/iet-map.2014.0402
Subject(s) - band pass filter , electronic engineering , transmission (telecommunications) , computer science , electrical engineering , topology (electrical circuits) , engineering , telecommunications
Two novel bandpass filters with multiple transmission zeros using open/shorted stubs are presented in this study. By utilising shorted coupled lines and the open/shorted stubs, five and eight out‐of‐band transmission zeros can be realised for the two bandpass filters from 0 to 2 f 0 ( f 0 is the centre frequency of the passband). Five and eight transmission zeros can be adjusted freely by only changing the electrical length of the open/shorted stubs. Two planar bandpass filters (3‐dB fractional bandwidths 7.44%, 3.88–4.18 GHz and 7.5%, 3.85–4.15 GHz) are designed and fabricated. The theoretical and measured results all show good in‐band filtering performances and high selectivity.