Extended Quasi Orthogonal Functions for 3G CDMA Systems

3G CDMA 시스템을 위한 확장 준직교 함수

  • Lee Kwang-Jae (Department of Inform. & Telecomm. Engineering, Hanlyo University) ;
  • Moon Myung-Ryong (Department of Digital & Electrical Information, Jeonju Technical college) ;
  • Hou Jia (Institute of Information & Communication) ;
  • Lee Moon-Ho (Institute of Information & Communication)
  • 이광재 (한려대학교 멀티미디어정보통신공학과) ;
  • 문명룡 (전주공업대학 디지털전기정보과) ;
  • ;
  • 이문호 (전북대학교 정보통신연구소)
  • Published : 2005.07.01

Abstract

The forward link of the 3G CDMA system may become limited under the increasing of the number of users. The conventional channelization code, Walsh code, has not enough sizes f3r much possible users, therefore, the quasi orthogonal function(QOF), which process optimal crosscorrelation with Walsh code, is considered. In this paper, we investigate quasi orthogonal function on Jacket matrices, which can lead lower correlations values and better performance in 3G CDMA system. Moreover, to simplify the detector and improve the BER performance, a novel detection for QOF CDMA system is proposed. Finally, the simple recursive generation of the bent sequences for QOF mask function is discussed.

3G CDMA 시스템의 순방향 링크는 사용자 수의 증가에 따른 제한을 받게 된다. 기존의 채널 구분을 위한 부호인 Walsh 부호는 많은 사용자에 대 한 충분한 크기를 갖지 못하므로, Walsh 부호와 최적의 상관 특성을 갖는 준직교 부호(QOF: Quasi Orthogonal Function)가 고려되고 있다. 본 논문에서는 3G CDMA 시스템에서 더 낮은 상관 값과 우수한 성능을 갖는 재킷 행렬 상에서의 준직교 수열 생성에 관해 고찰하였다. 또한 QOF CDMA 시스템의 검파기의 단순화 및 BER 성능 개선을 위한 새로운 검파 구조를 제시하였다. 마지막으로, QOF 마스크 함수를 위한 bent 수열의 간단한 반복 생성에 대해 고찰하였다.

Keywords

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