The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Proposal Of Optimum Equalizer Hardware Architecture for Cable Modem and Analysis of Various LMS Algorithms

케이블모뎀용 등화기에 적용되는 다양한 LMS알고리즘에 관한 성능평가 및 최적의 등화기 하드웨어구조 제안

  • 조연곤 (성균관대학교 전기전자 및 컴퓨터 공학부) ;
  • 유형석 (성균관대학교 전기전자 및 컴퓨터 공학부) ;
  • 김병욱 (성균관대학교 전기전자 및 컴퓨터 공학부) ;
  • 조준동 (성균관대학교 전기전자 및 컴퓨터 공학부) ;
  • 김재우 (삼성전자 SOC기술연구소) ;
  • 이재곤 (삼성전자 SOC기술연구소) ;
  • 박현철 (ICU)
  • Published : 2002.01.01
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Abstract

This paper presents the convergence time, SER(Symbol Error Rate), MSE(Mean Square Error), hardware complexity and step-size(${\mu}$) about various LMS(Least Mean Square) algorithms in FS-DFE(Fractionally Spaced-Decision Feedback Equalize) for Cable Modem based on MCNS(Multimedia Cable Network System) DOCSIS(Data Over Cable Service Interface Specification) v1.0/v1.1 standards. We designed and simulated using ${SPW}^{TM}$ and synthesized using STD90 library through ${SYNOPSYS}^{TM}$. And also, we adopted the time-multiplexed multiplication and tap shared architecture in order to achieve the low hardware complexity. Simulation results show that DS-LMS algorithms[1][3] is the optimum solution about performace and hardware size. in high order QAM applications. Finally, we achieved area saving about 58% using DS-LMS algorithm compare with conventional equalizer architecture.

본 논문지 MCNS(Multimedia Cable Network System) DOCSIS(Data Over Cable Service Interface Specification) v1.0/v1.1 표준안에 대응하는 케이블모뎀 수신단의 FS-DFE(Fractionally Spaced-Decision Feedback Equalize)에 적용될 다양한 LMS(Least Mean Square)알고리즘에 관하여 수렴특성, SER(Symbol Error Rate) 및 MSE(Mean Square Error) 성능, 하드웨어 복잡도 그리고 step-size(${\mu}$)와의 관계를 $SPW^{TM}$로 모델링하고, 그들 개개의 성능을 보여다. 그리고 Verilog-HDL을 이용하여 RTL 구조를 구성하였고, $SYNOPSYS^{TM}$을 통해 삼성 STD90 라이브러리로 합성하였다. 또한 본 논문에서는 최적의 하드웨어 구조를 가지기 위한 time-multiplexed multiplication 과 tap shared architecture구조를 채택하였다. 실험 결과를 통하여 LMS, DS(Data Signed)-LMS, ES(Error Signed)-LMS, SS(Signed Signed)-LMS[1][3]과 같은 다양한 LMS 알고리즘들 중 DS-LMS 알고리즘이 성능과 하드웨어를 고려한 최적의 알고리즘임을 보였고, DS-LMS 알고리즘 및 여러 가지 저면적 점유 기법을 이용하여 최대 58%까지 하드웨어 면적을 줄일 수 있었다.

Keywords

References

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