Premium
A stub‐loaded SIR filter with an ultra‐wide rejection band
Author(s) -
Wang Huan,
Chu QingXin
Publication year - 2009
Publication title -
microwave and optical technology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.304
H-Index - 76
eISSN - 1098-2760
pISSN - 0895-2477
DOI - 10.1002/mop.24740
Subject(s) - stub (electronics) , stopband , resonator , microwave , electrical impedance , physics , acoustics , electrical engineering , engineering , electronic engineering , materials science , optoelectronics , telecommunications
A stub‐loaded stepped‐impedance resonator (SIR) filter with an ultra‐wide upper stopband is proposed. For a 20‐dB rejection level, by properly choosing the number and lengths of the stubs, the second, third, and fourth resonances of the SIR filter are pushed to left and the seventh resonance is pushed to right, and all of them show low S 21 levels due to the improper external coupling values, while the fifth and sixth resonances are greatly suppressed by a transmission zero. The measured 20‐dB rejection band of a three‐stub SIR filter achieves 17.4 times the designed frequency. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2660–2662, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24740