Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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An Alternating Equalizer with Differential Adjustment Based on Symbol Decisions by Soft/Hard Decision

연/경판정에 의한 심벌 판정 기반의 차등 조정 교번 등화기

  • Oh, Kil-Nam (Dept. of Optical Communications Engineering, Gwangju University)
  • 오길남 (광주대학교 광통신공학과)
  • Received : 2012.02.13
  • Accepted : 2012.05.10
  • Published : 2012.05.31
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Abstract

In this paper, a new alternating equalizer and its differential adjustment algorithm are proposed. The proposed alternating equalizer achieves equalization effectively using an algorithm performing symbol decisions based on soft/hard decision. In addition, it is possible to improve the initial blind convergence speed and steady-state error performance simultaneously by adjusting the equalizer differentially according to the relative reliability of the symbol decisions by soft/hard decision devices. The simulation results on 16/64-QAM constellations under multipath propagation channel and additive noise conditions confirmed to support usefulness of the proposed method.

본 논문에서는 새로운 교번 등화기와 이를 조정하기 위한 차등 조정 알고리즘을 제안한다. 제안하는 교번 등화기는 연판정과 경판정 기반의 심벌 판정을 수행하는 알고리즘을 사용하여 등화기를 번갈아 동작시키는 방식으로 블라인드 등화를 효과적으로 달성한다. 아울러 연판정과 경판정에 의한 심벌 판정의 상대적 신뢰도에 따라 등화기를 차등 조정함으로써 초기 블라인드 수렴 속도와 정상상태 오차 성능을 동시에 개선하는 것이 가능하다. 다중경로 전파 채널과 부가 잡음 조건에서 16/64-QAM 신호점에 대한 모의실험 결과가 제안 방식의 유용성을 뒷받침하는 것을 확인하였다.

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References

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