Sharp Roll-Off Ultra Wide Stopband Compact Microstrip Lowpass Filter Using Square-Shaped Resonator

  • Behnam Afzali Department of Electrical Engineering, Faculty of Technical and Vocational No.2, Kermanshah Branch, Technical and Vocational University (TVU), Kermanshah, Iran.
  • Farshid Yousefi Moghadam Department of Electrical Engineering, Faculty of Technical and Vocational No.2, Kermanshah Branch, Technical and Vocational University (TVU), Kermanshah, Iran.
  • Farshad Nadi Department of Electrical Engineering, Faculty of Technical and Vocational No.2, Kermanshah Branch, Technical and Vocational University (TVU), Kermanshah, Iran.
  • Rohallah Zallbeygi Department of Electrical Engineering, Faculty of Technical and Vocational No.2, Kermanshah Branch, Technical and Vocational University (TVU), Kermanshah, Iran.
Keywords: Cut off frequency, Filter, LC equivalent, Lowpass, Microstrip, Resonator, Sharp roll-off, Square-shaped, Transformation function, Ultra wide stopband.

Abstract

In this paper, a novel compact microstrip lowpass filter (LPF) with sharp roll-off and ultra wide stopband with high suppression level is presented. In the proposed filter, square-shaped resonators were used. The cut off frequency at 3dB was 1.88GHz. The maximum insertion loss of this filter was less than 0.1dB and the return loss was also less than 16dB in the passband. In the proposed structure, the stopband extends from 2.07 to 29.5 GHz at 24dB level of suppression and was considered as an ultra-wide stopband. There was a significant relationship between simulation and fabrication results.

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Published
2019-01-13
How to Cite
Afzali, B., Yousefi Moghadam, F., Nadi, F., & Zallbeygi, R. (2019). Sharp Roll-Off Ultra Wide Stopband Compact Microstrip Lowpass Filter Using Square-Shaped Resonator. Majlesi Journal of Electrical Engineering, 13(2). Retrieved from http://mjee.iaumajlesi.ac.ir/index/index.php/ee/article/view/2876
Section
Articles