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 Novel Compensation Scheme for I/Q Mismatch in an OFDM Direct-Conversion Architecture

OFDM 전송방식 기반의 Direct-Conversion 수신기에서 I/Q 불균형 보상을 위한 새로운 방법 제안

  • 배정화 (고려대학교 전자컴퓨터공학과 무선통신시스템연구실) ;
  • 박진우 (고려대학교 전자컴퓨터공학과 무선통신시스템연구실)
  • Published : 2006.12.30
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Abstract

This paper proposes a compensation method that can alleviate the problem of I/Q mismatch generated in the direct-conversion receiver of OFDM systems. In the proposed method, the amount of I/Q mismatch is estimated using null-carriers in transmitted signals, and it is subtracted from received symbols to suppress I/Q mismatch effects. Simulations show experiments that the proposed method can effectively eliminate the I/Q mismatch effects.

본 논문에서는 OFDM을 기반으로 하는 직접변환(Direct-conversion) 수신기에서 발생하는 I/Q 불균형(mismatch)문제를 효과적으로 제거할 수 있는 새로운 보상기법을 제시한다. OFDM심볼에 0의 값을 갖는 null 부반송파를 삽입하여 전송한 후에, 수신단에서 FFT후의 null 부반송파로부터 I/Q 불균형 관한 파라미터 값을 추정하고, 이를 이용하여 데이터 심볼에서 I/Q 불균형 효과를 제거하는 방법으로, 효율적이며 낮은 복잡성(complexity)이 제안 방식의 수요 특징이다. 모의실험 결과로부터 소수의 null 부반송파로도 충분한 I/Q 불균형 효과를 제거하는 결과를 얻을 수 있었다. 또한 제안된 방식은 주파수 선택적 페이딩 채널에서도 I/Q 불균형이 잘 제거됨을 보였다.

Keywords

References

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