基于动量因子的变步长盲多用户检测器

Changeable step blind multi-user detector based on momentum factor

针对3种经典的盲多用户检测算法中,最小均方误差(LMS)算法收敛速度慢、而递归最小二乘算法(RLS)和Kalman自适应算法计算复杂度高的问题,该文提出了一种基于动量因子的变步长LMS算法。该算法在初始阶段使用较大的步长值,根据同一接收信号在相邻两次迭代过程中检测器的输出值之差来动态调整步长,加快了LMS算法的收敛速度。仿真结果表明,该算法的收敛和检测性能明显好于传统的LMS算法,稳态输出接近RLS算法和Kalman算法,而计算量仅略高于传统LMS算法,可以实时有效地抑制多址干扰。

For the three classical blind multiuser detection algorithms,the convergence rate of the least mean squares（LMS）is slower,and the recursive least squares（RLS） and the Kalman algorithm have higher computational complexity,a new changeable step algorithm based on the momentum factor is proposed. By using a larger step value in initial moment and dynamically adjusting step in iteration phases according to the detector output error of the same symbol received in two adjacent iteration processes,the algorithm has the better convergence performance. Simulation results show that the convergence performance of the improving algorithms is better than that of the classical LMS,the stable output performance is close to that of the RLS and Kalman,and the computational complexity is alittle higher than that of the LMS. The method can instantaneously and effectively suppress the multiaccess interference.