Journal of Advanced Marine Engineering and Technology

The Korean Society of Marine Engineering (한국마린엔지니어링학회)
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Design of an extremely miniaturized branch-line coupler

  • Kang, In Ho (Department of Radio Sciences and Engineering, Korea Maritime & Ocean University) ;
  • Li, Xi Qiang (Department of Radio Sciences and Engineering, Korea Maritime & Ocean University)
  • Received : 2014.05.14
  • Accepted : 2014.10.12
  • Published : 2014.10.31
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Abstract

In this paper, a new size-reduction approach for branch-line coupler is introduced which uses parallel end-shorted coupled lines with lumped capacitors. The characteristic of the new design was analyzed using even-odd mode method, and simulated on HFSS before fabricated on the FR4 epoxy glass cloth copper-clad plat (CCL) PCB substrate at center frequency of 1 GHz. The electrical length of transmission line was reduced to 15 degrees, therefore the size of branch-line coupler was largely reduced approximately maintaining the same characteristic around the stable center frequency. The insertion loss of the branch-line coupler filter was -4.39 dB. The size of the overall hybrid is $20mm{\times}20mm$. Measurements results were well agreed with the simulated ones.

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References

  1. Y. C. Chiang and C. Y. Chen, "Design of a wide-band lumped-element 3-dB quadrature coupler," IEEE Transactions Microwave Theory Technic, vol. 49, no. 3, pp. 476-479, 2001. https://doi.org/10.1109/22.910551
  2. T. Hirota, "Reduced-size branch-line and rat-race hybrids for uniplanar MMIC's," IEEE Transactions .Microwave Theory Technic, vol. 38, no. 3, pp. 270-275, 1990. https://doi.org/10.1109/22.45344
  3. I. Kang and J. S. Park, "A reduced-size power divider using the coupled line equivalent to a lumped inductor," Journal of Microwave, vol. 46, no. 7, pp. 82-88, 2003.
  4. D. M. Pozar, Microwave Engineering, Wiley, New York, 1998.