一种改进变步长LMS算法及其DSP功能实现  

A improved variable step size LMS algorithm and its DSP function realization

作　　者：牛群 陈天宁[1,2] Niu Qun;Chen Tianning(School of Mechanical Engineering, Xi＇an Jiaotong University, Xi＇an 710049, China;State Key Laboratory for Strength and Vibration of Mechanical Structures, Xi＇an Jiaotong University, Xi＇an 710049, China)

机构地区：[1]西安交通大学机械工程学院,西安710049 [2]西安交通大学机械结构强度与振动国家重点实验室,西安701149

出　　处：《电子测量技术》2018年第7期83-88,共6页Electronic Measurement Technology

摘　　要：自适应滤波LMS算法在自适应系统中应用十分广泛,变步长LMS算法在一定程度上改善了经典LMS算法收敛速度与精度的对立关系,在已有算法的基础上提出一种改进的变步长LMS自适应滤波算法,利用权系数w（n）的梯度变化量在保证收敛精度的基础上进一步加快收敛速度,同时调整了步长更新公式,增强了算法抵抗噪声干扰的能力,最后通过MATLAB实际仿真表明该算法具有更快的收敛速度,更小的稳态误差,更好的鲁棒性,并在DSP环境下的噪声消除系统中取得了较好的效果。LMS adaptive filtering algorithm is widely used in adaptive system.To a certain extent the variable step size LMS algorithm can solve the conflict between convergence rate and steady-state error.It is difficult for the traditional LMS to solve.A new variable step size LMS adaptive algorithm based on the existing algorithm is proposed in this paper.By using the gradient of the filter coefficient W（n）the algorithm accelerates the convergence speed on the basis of ensuring the convergence accuracy.At the same time,the update formula of step size is adjusted to enhance the ability of the algorithm to resist noise interference.Finally,the MATLAB simulation results show that the algorithm has faster convergence speed,smaller steady-state error and better robustness.And it has good results in the noise cancelling system in the DSP environment.

关 键 词：自适应滤波 LMS算法 变步长 噪声抵消 DSP 

分 类 号：TN911.7[电子电信—通信与信息系统]