一种改进的变步长LMS自适应滤波算法

An Improved LMS Adaptive Filtering Algorithm with Variable Step Size

提出一种改进的变步长LMS(Least Mean Square)算法,该算法在步长参数μ与误差信号e(n)之间建立了一种非线性函数关系,并且分析了参数α,β的取值原则及对算法收敛性能的影响。该关系具有在误差e(n)接近零处缓慢变化的优点,克服了s函数变步长LMS算法在自适应稳态阶段μ(n)取值偏大的缺陷。理论分析和计算机仿真结果表明,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。

By building a nonlinear functional relationship between μ and the error signal e(n),this paper proposes an improved variable step size LMS(Least-Mean-Square)adaptive filtering algorithm.and analyzes the algorithm with various α and β.This variable step size algorithm avoids the shortcoming of changing step size of SVSLMS(variable step size LMS based on Sigmoid function).Also in the stage of adaptive steady state it has the virtue of e(n) slightly changing at point close to zero.Theoretical analysis and comp...