The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Design of Asymmetrical Coupled Microstrip BandPass Filter on Composite Dielectric Substrate

복합 유전체기판상에 비대칭 결합 마이크로스트립 대역통과필터의 설계

  • 김익수 (인천대학교 정보통신공학과) ;
  • 문승찬 (강릉영동대학 정보통신과)
  • Published : 2004.01.01
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Abstract

Parallel coupled microstrip bandpass filter is widely used in microwave circuits. But this filter limits the filter applications because of the narrow bandwidth and the spurious passband at twice the basic passband frequency. In order to solve this problem, a method of the asymmetrical coupled microstrip lines on composite dielectric substrate is presented. Closed form method is used to analyze the asymmetrical coupled microstrip lines on composite dielectric substrate. An experimental filter is fabricated over $33\%$ bandwidth centered at 9GHz. Compared with the filter on a single substrate, this filter on composite substrate shows improvement of the spurious passband.

초고주파 회로에서 광범위하게 이용되는 평행 결합 마이크로스트립 대역통과필터는 좁은 대역폭 과 2차 스프리어스 통과대역으로 필터의 응용을 제한한다. 이와 같은 문제를 해결하기 위해서 복합 유전체기판상에 비대칭 결합 마이크로스트립 선로를 이용하는 방법을 제시하였다. closed-form해석방법을 이용하여 복합 유전체기판상에 비대칭 결합 마이크로스트립 선로를 해석하고 중심주파수 9GHz 에서 정규화 대역폭 $33\%$을 갖는 필터를 제작하였다. 단층기판을 갖는 필터와 비교하면 복합 유전체기판을 이용한 필터는 스프리어스 통과대역이 약 20dB 이상 개선됨을 보였다

Keywords

References

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