Analysis and Utilization of the Power Delay Profile Characteristics of Dispersive Fading Channels

시간 지연을 갖는 페이딩 채널의 전력 지연 분포 특성 분석 및 활용

  • 박종현 (서강대학교 전자공학과 디지털전송연구실) ;
  • 김재원 (서강대학교 전자공학과 디지털전송연구실) ;
  • 송의석 (서강대학교 전자공학과 디지털전송연구실) ;
  • 성원진 (서강대학교 전자공학과 디지털전송연구실)
  • Published : 2007.08.31

Abstract

Applying an appropriate received signal processing algorithm based on the channel characteristics is important to improve the receiver performance. Wireless channels in general exhibit various time-delay characteristics depending on their power delay profile. When the estimated channel power summation is used to determine the amount of time delay, a channel adaptive receiver structure can be implemented. In this paper, we derive a closed-form expression for the error probability of the channel classification when the estimated channel power summation is used to classify channel groups having different time delay characteristics, and present the performance gain utilizing multiple estimation results.

통신 수신기 구현에 있어 채널의 특성을 파악하여 그에 적합한 수신 신호 처리를 수행하는 것은 수신 성능 향상을 위해 매우 중요하다. 무선 채널은 전력 지연 분포(power delay profile)에 따라 다양한 시간 지연 특성을 가지며, 추정된 채널의 전력 합산을 통해 시간 지연 정도를 판별 시, 채널 적응적인 수신 구조 구현이 가능하다. 본 논문에서는 전력 지연 분포의 합산을 통해 시간 지연의 상대적인 크기에 따른 채널 군으로 분류하는 경우에 있어 채널 판별 오류 확률을 closed-form 수식으로 유도하고, 다수 번의 추정 결과를 누적하여 활용 시 얻어지는 성능 이득을 제시한다.

Keywords

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