关键词: 盲多用户检测, 独立分量分析, 直接序列扩频码分多址（DS-CDMA）系统, 罗克拉美下界

Abstract: The noise signal is often neglected for Independent Component Analysis algorithms（ICA） for blind multiuser detection put forward; it leads the detection performance of Direct Sequence spread spectrum Code Division Multiple Address（DS-CDMA） system to decrease. The noise term is taken into account. The improved ICA for blind multiuser detector is proposed. The algorithm can not only suppress Near-Far Effects and Multi-Access Interference but also reduce the noise term neglected as far as possible by signal subspace and effective unbiased estimate, to gain the capacity of the system. Simulation results demonstrate that the proposed method is effective and practicable.

Key words: blind multiuser detection, Independent Component Analysis（ICA）, Direct Sequence spread spectrum Code Division Multiple Address（DS-CDMA） systems, Cramer-Rao lower bound