四川大学学报（自然科学版）2011，Vol.48Issue(1)：92-98,7.DOI:10.3969/j.issn.0490-6756.2011.01.017
多径MIMO CDMA系统中改进的盲空时多用户检测算法
An improved blind space-time multiuser detection algorithm for asynchronous MIMO CDMA system
摘要
Abstract
An improved blind linear minimum-mean-square-error(MMSE) space-time multiuser detector (MUD)and its adaptive implementation based on a signal subspace tracking algorithm is presented for the asynchronous multiple input multiple output Direct Sequence Code Division Multiple Access (MIMO DS/CDMA ) communication system in fading multipath channels. The Alamouti space-time block coding (STBC) scheme is adopted to achieve the spatial diversity on transmit antennas. Some attempts are exploited to improve the performance of the system. The signal subspace can be pretreated by modifying a rough estimated signal subspace with the prior knowledge of the desired user signature waveform and the available information of MIMO wireless channels. Then the proposed detector employs the normalized orthogonal Oja (NOOja) algorithm for subspace estimation, since it guarantees the better stability and orthogonality of the signal subspace in every iteration than other subspace tracking algorithms. The eigenvalue matrix is dealt with to remove noise in initial stage of the adaptive process. The numerical simulation results show that this algorithm is efficient to suppress multiple access interference (MAI) and combat the near-far effect. In particular, it has good tracking ability and steady-state performance in the low SNR and distinct near-far effect environment.关键词
多输入多输出/盲多用户检测/修正信号子空间/空时分组码/NOOjaKey words
Multiple input multiple output(MIMO)/blind multiuser detection/modified signal subspace/ space-time block coding(STBC)/ NOOja分类
信息技术与安全科学引用本文复制引用
于文君,何培宇,黄如浩,高勇..多径MIMO CDMA系统中改进的盲空时多用户检测算法[J].四川大学学报（自然科学版）,2011,48(1):92-98,7.基金项目
通信抗干扰技术国家重点实验室资助项目(JG2007055) （JG2007055）
