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

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Convergence Property Analysis of Multiple Modulus Self-Recovering Equalization According to Error Dynamics Boosting

다중 모듈러스 자기복원 등화의 오차 역동성 증강에 따른 수렴 특성 분석

  • Oh, Kil Nam (Dept. of Optical Communications Engineering, Gwangju University)
  • 오길남 (광주대학교 광통신공학과)
  • Received : 2015.09.22
  • Accepted : 2016.01.05
  • Published : 2016.01.31
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Abstract

The existing multiple modulus-based self-recovering equalization type has not been applied to initial equalization. Instead, it was used for steady-state performance improvement. In this paper, for the self-recovering equalization type that considers the multiple modulus as a desired response, the initial convergence performance was improved by extending the dynamics of the errors using error boosting and their characteristics were analyzed. Error boosting in the proposed method was carried out in proportion to a symbol decision for the equalizer output. Furthermore, having the initial convergence capability by extending the dynamics of errors, it showed excellent performance in the initial convergence rate and steady-state error level. In particular, the proposed method can be applied to the entire process of equalization through a single algorithm; the existing methods of switching over or the selection of other operation modes, such as concurrent operating with other algorithms, are not necessary. The usefulness of the proposed method was verified by simulations performed under the channel conditions with multipath propagation and additional noise, and for performance analysis of self-recovering equalization for high-order signal constellations.

기존의 다중 모듈러스 기반 자기복원 등화 유형은 등화 초기에 적용되지 못하고 정상상태 성능 개선에 활용되었다. 본 논문에서는 다중 모듈러스를 원하는 응답으로 하는 유형의 자기복원 등화에서, 오차를 증강하여 오차의 역동성을 확장함으로써 초기 수렴 성능을 개선하고, 그 특성을 분석하였다. 제안 방법에서 오차 증강은 등화기 출력에 대한 심볼 판정에 비례하여 이루어진다. 아울러 제안 방법은 오차 역동성의 확장으로 인한 초기 수렴 기능을 갖기 때문에, 초기 수렴속도와 정상상태 오차 레벨에서 우수한 성능을 보인다. 특히 제안 방법은 등화의 전 과정을 하나의 알고리즘으로 진행하므로 기존의 다른 동작 모드로의 전환이나 선택 방법, 또는 다른 알고리즘과의 동시 동작 등이 불필요하다. 다중경로 전파와 부가 잡음이 있는 채널 조건하에서 이루어진 고차 신호점에 대한 자기복원 등화의 성능 분석 시뮬레이션을 통해 제안 방법의 유용성을 검증하였다.

Keywords

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