The Journal of Korean Institute of Electromagnetic Engineering and Science (한국전자파학회논문지)

The Korean Institute of Electromagnetic Engineering and Science (한국전자파학회)
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A Design of Spurious-Reduced CPW Low-Pass Filter Based on Defected Ground Structure

고조파 제거 특성을 갖는 DGS 형태의 CPW 저역 통과 여파기의 설계

  • No Jin-Won (Department of Electronical & Electronics Engineering, Kangwon University) ;
  • Choi Kyoung (Department of Electronical & Electronics Engineering, Kangwon University) ;
  • Hwang Hee-Yong (Department of Electronical & Electronics Engineering, Kangwon University)
  • 노진원 (강원대학교 전기전자공학과) ;
  • 최경 (강원대학교 전기전자공학과) ;
  • 황희용 (강원대학교 전기전자공학과)
  • Published : 2006.02.01
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Abstract

In this paper, a CPW lowpass filter with the spurious-reduced characteristic is designed by using DGS(Defected Ground Structures). By cascading two lowpass filters with different harmonic characteristics the spurious is reduced below - 15 dB. Additionally by combining a dumbbell shaped DGS to the filter we achieved a satisfactory spurious level of less than -25 dB to above three times cutoff frequency without any repeated passband. The fabricated LPF shows a compact size of $17.2mm{\times}6.8mm$, a cutoff frequency of 6 GHz, and a sharp skirt response of 7-order with two notch frequencies. The measured frequency responses agree well with simulated ones.

본 논문에서는 고조파 제거 특성을 갖는 DGS 형태의 CPW 저역 통과 여파기를 설계하였다. 서로 다른 불요응답 특성을 갖는 2개의 저역 통과 여파기를 설계하고 결합하여 불요 응답을 -15 dB 이하로 줄일 수 있었다. 추가적으로 아령 모양의 DGS를 설계하여 여파기와 결합함으로써 -25 dB 이하의 우수한 불요 응답제거 특성을 얻을 수 있었다. 제작된 여파기는 $17.2mm\times6.8mm$의 작은 크기로, 6 GHz의 차단 주파수를 가지며, 2개의 감쇄극을 갖는 7차의 급격한 감쇄 특성을 나타내었다. 측정된 주파수 특성 결과는 시뮬레이션 결과와 잘 일치하였다.

Keywords

References

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