Wireless Personal Communications

, Volume 99, Issue 1, pp 497–507 | Cite as

High Performance Microstrip Low Pass Filter for Wireless Communications

  • Saeed RoshaniEmail author
  • Alireza Golestanifar
  • Amirhossein Ghaderi
  • Hesam Siahkamari
  • Derek Abbott


A microstrip low-pass filter using T-shaped resonators is designed to achieve an ultra-sharp transition band and high suppression level. The performance of the resonators is investigated based on an LC equivalent circuit and a transfer function to compute the equations of the transmission zeros. This filter has an acceptable stopband with high insertion loss (28 dB) by adopting a rectangular suppressor. Also, the width of the transition band is 0.09 GHz (with – 3 and − 40 dB attenuation levels), that exhibits a very high sharpness (ξ = 411 dB/GHz). The proposed filter with a 3 dB cut-off frequency (fc) of 1.32 GHz presents a high return loss in the passband (17 dB) and high figure of merit of 57,073. The designed filter is fabricated and measured, demonstrating sufficient agreement between the simulation and experimental results.


T-shaped resonator LC equivalent circuit Microstrip filter Rectangular stub 



The authors would like to thank the Kermanshah Branch, Islamic Azad University for the financial support of this research project.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2017

Authors and Affiliations

  • Saeed Roshani
    • 1
    Email author
  • Alireza Golestanifar
    • 2
  • Amirhossein Ghaderi
    • 2
  • Hesam Siahkamari
    • 2
  • Derek Abbott
    • 3
  1. 1.Department of Electrical Engineering, Kermanshah BranchIslamic Azad UniversityKermanshahIran
  2. 2.Young Researchers and Elite Club, Kermanshah BranchIslamic Azad UniversityKermanshahIran
  3. 3.School of Electrical and Electronic EngineeringUniversity of AdelaideAdelaideAustralia

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