Griffiths' Algorithm Based Adaptive LMMSE Equalizers for HSDPA MIMO Systems

HSDPA MIMO 시스템을 위한 Griffiths 알고리즘 기반 적응 LMMSE Equalizer

  • 주정석 (한국외국어대학교 전자공학과)
  • Received : 2011.08.21
  • Published : 2011.11.25

Abstract

In CDMA-based systems, recently, researches on chip-level equalization have been studied in order to improve receiving performance when supporting high-rate data services. In this paper, we propose Griffiths' algorithm based chip-level adaptive LMMSE equalizers for HSDPA MIMO systems using D-TxAA (dual stream transmit antenna array). First, we will derive two possible structures of Griffiths' algorithm based equalizer, and then compare their performance through computer simulations in various mobile channel environments.

최근 들어 CDMA 기반 시스템에서 고속 데이터 서비스 지원을 위한 수신 성능 개선 방법의 하나로 chip-level equalization 기법에 대한 연구가 활발히 진행되고 있다. 이와 관련된 연구의 하나로 본 논문에서는 D-TxAA (dual stream transmit antenna array) 방식을 사용하는 HSDPA MIMO 시스템에 적용 가능한 Griffiths algorithm 기반 chip-level 적응 LMMSE equalizer의 구조를 제안하고자 한다. 먼저 Griffiths 알고리즘을 D-TxAA 방식에 적용할 경우 사용 가능한 두 가지 형태의 적응 LMMSE equalizer 구조를 유도할 것이며, 여러 채널 환경에 대한 컴퓨터 모의실험을 통해 두 수신기의 성능을 비교 분석하고자 한다.

Keywords

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