码分多址(Code-Division Multiple-Access,CDMA)系统中,采用盲多用户检测算法抑制多址干扰(Multiple Access Interference,MAI)和"远-近"效应(Near-Far effect)的影响,是CDMA技术研究热点之一。为避免基于卡尔曼(Kalman)滤波的多用户检测算法中,协方差矩阵失去非负定性而面临的数值稳定性问题,提出利用QR分解方法重新构造系统模型协方差阵,建立一种收敛速度更快、数值鲁棒性更好的卡尔曼盲自适应多用户检测算法。仿真结果表明,该算法具有较好的抗多址干扰和抗"远-近"效应能力。
Blind multi-user detection methods in Code-Division Multiple-Access(CDMA)system are used to eliminate the Multiple Access Interference(MAI)and the Near-Far effect. For microprocessor or DSP has a limit word length, blind multi-user detection based on Kalman filter must face the problem of numeric stability. A new method based on QR factor is used in the blind multi-user detection based on Kalman filter. Simulation results show that this method is efficient in MAI and Near-Far effect elimination.