Journal of the Institute of Electronics Engineers of Korea TC (대한전자공학회논문지TC)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Compact Hybrid Branch-line Couplers and Rat-Race Couplers with Periodic Stepped Stubs

주기적인 계단형 스터브를 갖는 소형화된 하이브리드 Branch-Line 결합기와 Rat-Race 결합기

  • Lee Chang On (Division of Electrical and Computer Engineering, Ajou University) ;
  • Kim Won-Ki (Division of Electrical and Computer Engineering, Ajou University) ;
  • Kim Sang-Tae (ITEP) ;
  • Shin Chull-Chai (Division of Electrical and Computer Engineering, Ajou University)
  • Published : 2004.12.01
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Abstract

In this paper, we introduce the advanced compact transmission line with periodic stepped stubs. They are more effective than normal stubs in ATL. The short stepped stubs loading of transmission line work as effective shunt capacitance and that was proved by equivalent circuit based on transmission line theory and quasi-static analysis. And the compact branch-line coupler and the compact rat-race coupler via proposed compact microstrip line were designed at 1.8 ㎓. They have 677 ㎟ and 913 ㎟, respectively, and they are 62% and 45% of normal design.

본 논문에서는 마이크로스트립 전송선로에 주기적으로 계단형 스터브를 부가하여 물리적 길이를 소형화시킨 마이크로스트립 전송선로를 나타내었다. 주기적인 계단형 스터브는 quasi-static analysis와 전송선 이론을 바탕으로 한 등가모델로 병렬로 부가된 커패시턴스 역할을 함을 보였으며, 기존의 일반 스터브를 이용한 경우보다 짧은 길이의 스터브로 높은 커패시턴스 부가 효과를 얻을 수 있음을 보였다. 그리고 이러한 선로를 이용하여 소형화된 branch-line 결합기와 rat-race결합기를 설계하였다. 1.8 ㎓에서 구현된 각각의 결합기는 677 ㎟, 913 ㎟으로 일반적인 결합기에 비해 그 크기가 62%, 45%로 다른 소자의 부가 없이 단지 전송선로의 변형만을 통해 매우 효과적으로 축소되었다.

Keywords

References

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