一种改进的变步长自适应滤波器LMS算法  

A Modified LMS Algorithm for Variable Step Size Adaptive Filters

作　　者：徐凯[1] 纪红[1] 乐光新[1] 

机构地区：[1]北京邮电大学电信工程学院,北京100876

出　　处：《电路与系统学报》2004年第4期115-117,共3页Journal of Circuits and Systems

基　　金：国家自然科学基金资助项目(90104018;60172052;60002009)

摘　　要：本文提出一种改进的LMS算法(即MS-LMS),并建立了步长因子与误差信号)(ne之间另一种新的非线性函数关系。该关系不仅具有原有算法在误差)(ne接近零处缓慢变化的优点,而且低信噪比环境下比原有算法具有更好的收敛性能。理论分析和计算机仿真结果表明,在低信噪比的环境下,改进算法的收敛速度和稳态误差的性能指标都有较大的提高,并对系统发生的突变表现出较强的鲁棒性。A modified LMS algorithm, which establishes another new non-linear functional relationship between m and e(n), is proposed. This functional relationship not only has the virtue of e(n) slightly changing close to zero, but also has better performance than that of the former algorithms in the low SNR circumstance. Theoretical analysis and computer simulations show that with the proposed algorithm, convergence rate and misadjustment can be improved than the former in low SNR environments. Simulations also show that the algorithm is robust against to the abrupt change of the system.

关 键 词：自适应滤波 变步长自适应滤波算法 LMS算法 均方误差 

分 类 号：TN91[电子电信—通信与信息系统]