A New Asymmetric Branch Line Hybrid Coupler without Ground Contact Problem of DGS

접지 접촉 문제가 없는 새로운 DGS 비대칭 브랜치 라인 하이브리드 결합기

  • 임종식 (순천향대 전기통신공학과) ;
  • 차현원 (순천향대 전기통신공학과) ;
  • 정용채 (전북대 전자정보공학부) ;
  • 박웅희 (강원대 삼척캠퍼스 전자공학과) ;
  • 안달 (순천향대 전기통신공학과)
  • Published : 2008.08.01

Abstract

A 10 dB branch line hybrid coupler included with defected ground structure (DGS) is proposed. In this contribution, a contact between the grounded metal housing and DGS is avoided, which has been a serious problem in applying DGS to high frequency circuits. An isolation between the metal housing and the DGS pattern is provided by inserting additional substrate between DGS and the metal package. Therefore, it is possible to design branch line hybrid couplers having highly asymmetric power dividing ratio using these DGS structure, which is demonstrated in this paper. The designed and fabricated branch line hybrid coupler using DGS is well packaged in a metal housing without touching the ground metal directly. The measurement is performed under realistic practical operating situations because it is packaged in a metal housing. The measured performances of the fabricated 10dB coupler shows a 1:9 asymmetric power dividing ratio at output ports, as predicted. In addition, the measured performances in terms of matching, isolation, and phase difference are in excellent agreement with the simulated characteristics.

Keywords

References

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