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

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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A Simplified Time Domain Channel Tracking Scheme in OFDM Systems with Null Sub-Carriers

Null 부반송파를 갖는 OFDM 시스템에서 단순화된 시간영역 채널 추적 방식

  • 전형구 (동의대학교 정보통신공학과)
  • Published : 2007.04.30
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Abstract

This paper proposes a scheme to track channel response in OFDM systems with null sub-carriers. The proposed channel tracking scheme estimates the channel response first in the frequency domain by using the decision directed data. The time domain channel estimation is then performed to remove additive white Gaussian noise (AWGN) components further. Due to the channel estimation in the frequency domain, no inverse matrix calculation is required in the time domain channel estimation. Computational reduction in the proposed method is about 93%, compared with the conventional time domain channel estimation method. Mean square error (MSE) and bit error rate (BER) performances are evaluated by using computer simulation. The proposed method shows the same performance as that of the conventional time domain channel estimation even though the significant computational reduction.

본 논문에서는 null 부반송파를 갖는 OFDM 시스템에서 단순화된 시간 영역 채널 추적(tracking) 방식을 제안하였다. 제안된 채널 추적 방식은 결정 귀환된 데이터를 이용하여 간단한 주파수 영역 채널 추정을 먼저 수행함으로써 시간 영역 채널 추정을 간략화한 방식이다. 제안된 방식은 기존의 시간영역 채널 추정 방식 보다 계산량 면에서 약 93% 정도 감소한다. 본 논문에서 성능 분석은 추정된 채널 응답의 MSE 성능과 수신기의 BER 성능면에서 이루어졌다. 시뮬레이션 결과 제안된 방식은 줄어든 계산량에도 불구하고 기존의 시간 영역 채널 추적 방식과 동일한 성능을 보였다.

Keywords

References

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