Premium
Fractal‐shaped Hi‐Lo microstrip low‐pass filters with high passband performance
Author(s) -
Chen WenLing,
Wang GuangMing,
Qi YiNa
Publication year - 2007
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.22774
Subject(s) - passband , fractal , microstrip , filter (signal processing) , return loss , microwave , acoustics , physics , band pass filter , low pass filter , materials science , electronic engineering , engineering , optics , telecommunications , electrical engineering , mathematics , mathematical analysis , antenna (radio)
Hi‐Lo microstrip low‐pass filters using Koch fractal shapes are proposed for the first time. By constructing the low‐impedance sections in Koch‐shaped geometry, the passband performance of the Hi‐Lo microstrip low‐pass filter enhanced greatly. The excellent passband performance is mainly due to the gradual changes of the steps of the fractal‐shaped microstripline, thus to provide weak current discontinuities. To verify the proposed method, low‐pass filter prototypes of different iteration orders are designed, fabricated, and measured, and the measurement results show that the maximal sidelobe level of the passband return loss is reduced from −17.8 to −28.6 dB, and the other performances are not changed. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2577–2579, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22774