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 Soft Output Enhancement Technique for Spatially Multiplexed MIMO Systems

공간다중화 MIMO 시스템을 위한 Soft Output 성능향상 기법

  • 김진민 (중앙대학교 전자전기공학부 디지털통신연구실) ;
  • 임태호 (중앙대학교 전자전기공학부 디지털통신연구실) ;
  • 김재권 (연세대학교 원주캠퍼스 컴퓨터정보통신공학부) ;
  • 이주현 (삼성전자 정보통신연구소) ;
  • 조용수 (중앙대학교 전자전기공학부 디지털통신연구실)
  • Published : 2008.09.30
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Abstract

In spatially multiplexed MIMO systems that enable high data rate transmission over wireless communication channels, the spatial demultiplexing at the receiver is a challenging task and various demultiplexing methods have been developed. Among the previous methods, maximum likelihood detection with QR decomposition and M-algorithm (QRM-MLD), sphere decoding (SD), QOC, and MOC schemes have been reported to achieve a (near) maximum likelihood (ML) hard decision performance. In general, however, the reliability of soft output of these schemes is not satisfactory. In this paper, we propose a method which enhances the reliability of soft output. By computer simulations, we demonstrate the improved performance by the proposed method.

무선통신 채널에서 높은 전송 속도를 가능하게 하는 공간다중화 MIMO 시스템에서 다중화된 신호를 검출하는 것은 어려운 작업이며, 최근 다양한 신호검출 기법들이 개발되었다. 다양한 신호검출기법 중 maximum likelihood detection with QR decomposition and M-algorithm (QRM-MLD), sphere decoding (SD), QOC, MOC와 같은 기법들은 maximum liklihood (ha)기법과 유사한 경판정 달성한다. 그러나 일반적으로 이러한 기법들은 soft output의 신뢰도가 저하되는 문제점을 가진다. 본 논문에서는 기존 신호검출기법들의 soft output 신뢰도를 향상시키는 기법을 제안한다. 모의실험을 통하여 기존의 기법들과 결합시 제안된 방법에 의해 개선된 성능을 얻을 수 있음을 보인다.

Keywords

References

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