Journal of the Institute of Electronics Engineers of Korea TC (대한전자공학회논문지TC)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Filter Size Determination Algorithms for Decision-Directed Channel Estimators in Wideband CDMA Mobile Communication Systems

광대역 CDMA이동통신 시스템의 결정지향 채널추정기를 위한 필터크기 결정 방법

  • Rim, Min-Joong (Department of Information and Communication Engineering, Dongguk University) ;
  • Ryu, Chul (Department of Information and Communication Engineering, Dongguk University) ;
  • Ahn, Jae-Min (School of Electrical and Computer Engineering, Chungnam National University)
  • 임민중 (동국대학교 정보통신공학과) ;
  • 류철 (동국대학교 정보통신공학과) ;
  • 안재민 (충남대학교 정보통신공학부)
  • Published : 2003.05.01
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Abstract

CDMA(Code Division Multiple Access) mobile communication systems require accurate channel estimation in the receiver to compensate the fading distortions. Instantaneous channel estimates are obtained by dividing the received symbol by the transmitted symbol and then refined by filtering to reduce the estimation variance. In the channel estimation filter, the determination of the filter size is a very important task which greatly affects the estimation quality. While conventional methods usually use only velocity estimators to determine the channel estimation filter size, this paper proposes a filter size determination method for decision-directed channel estimators considering the symbol error rate and the signal-to-noise ratio in addition to the velocity of the mobile station. This paper shows that the symbol error rate and the signal-to-noise ratio are important factors for the determination of the channel estimation filter size.

CDMA(Code Division Multiple Access) 이동통신 시스템은 페이딩에 의한 왜곡을 보상하기 위해 수신기에서 정확한 채널추정을 요구한다. 순간채널추정값은 수신된 신호를 전송된 신호로 나누어 줌으로써 얻게 되며, 추정분산을 줄이기 위하여 필터를 통과함으로써 보다 정확한 채널추정값을 얻는다. 채널추정필터에서 필터 크기의 결정은 채널추정값의 정확도에 매우 큰 영향을 미치는 중요한 일이다. 기존의 논문들은 필터의 크기 결정을 위해서 일반적으로 속도 추정기만을 사용하지만, 이 논문에서는 결정지향 채널추정 방법의 채널추정필터를 위해서 단말기의 속도뿐만 아니라 심벌오류확률과 신호대잡음비를 고려한 필터 크기 결정 방법을 제안한다. 이 논문은 심벌오류확률과 신호대잡음비가 필터 크기를 결정할 때의 중요한 요소임을 보인다.

Keywords

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