Design and Characterization of 3 dB Branch Type Directional Couplers using High-Tc Superconductors

고온초전도체를 이용한 가지 형태 3 dB 방향성 결합기 설계 및 특성해석

  • 정동철 (우석대학교 전기전자공학과) ;
  • 최명호 (광주보건대학 의료공학과)
  • Published : 2010.01.01


In this work, we presented the characterization of 3 dB branch type directional couplers by using High-Tc superconducting thin films. To do this, we deposited YBCO superconducting thin films on MgO substrates by using rf-magnetron sputtering techniques. The designed center frequency was 408 MHz and the designed passband was 20 MHz. Also we designed 3 dB Power difference and $90^{\circ}$ of phase difference between port 3 and port 4. The even and odd mode analysis were used to characterize our directional couplers and em Sonnet (full wave analysis program) was utilized to the optimum design. We reported experimental results, including a center frequency, passband, half power characteristics and phase differences. We confirmed that experimental results were in good agreements with characterization by using full wave analysis program.


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