LMS和归一化LMS算法收敛门限与步长的确定  

DETERMINING OF CONVERGENT THRESHOLD AND STEP-SIZE FOR LMS AND NORMALIZED LMS ALGORITHM

作　　者：曾召华[1] 刘贵忠[1] 赵建平[2] 

机构地区：[1]西安交通大学电信学院,西安710049 [2]中兴通讯股份有限公司西安研究所,西安710065

出　　处：《电子与信息学报》2003年第11期1469-1474,共6页Journal of Electronics & Information Technology

基　　金：国家教育部高等学校博士学科点专项科研基金(No.2000069828);陕西省教育厅自然科学专项基金(No.01jk194)

摘　　要：从 LMS算法失调量的准确表达式出发,根据输入信号特征值分布重新研究了 LMS,归一化LMS(Normalized LMS,NLMS)算法收敛的必要条件,推导出 LMS和 NLMS 算法收敛的步长门限,并分析了输入信号特征值分布、滤波器阶数对算法收敛步长门限的影响,推导出满足性能失调下步长的自适应计算公式,减小了应用 LMS,NLMS算法时步长选取的盲目性,与已有的算法相比,具有计算简单、实用、自适应性能强,同时可获得满意失调量的特点,计算机模拟结果表明该方法的正确性。Based on eigenvalue distributing of input signal, the convergent necessary conditions for LMS and Normalized LMS(NLMS) algorithm are again researched through the accurate analysis of the misadjustment. To avoid blindness for applying LMS and NLMS algorithm, the convergent threshold and the simple adaptive calculating formula for the step-size of them are proposed. The influence of eigenvalue distributing of input signal and order of filter on the threshold of step-size is also analyzed. Compared with an existing algorithm, the characters of lower computational complexity, practicality and stronger adaptive are shown and the satisfied misadjustment is achieved by adopting the presented method for calculating the step-size.

关 键 词：LMS 归一化LMS算法 收敛门限 步长 输入信号特征值 

分 类 号：TN911[电子电信—通信与信息系统]