自适应噪声抵消技术中一种变步长的最小均方(LMS)算法研究  

A Modified Least Mean Square(LMS) Algorithm with Variable Step-size for an Adaptive Noise Canceller.

作　　者：高慧[1] 牛聪敏[2] 吴炜[3] 

机构地区：[1]北京理工大学,北京100081 [2]航天医学工程研究所,北京100094 [3]西安电子科技大学,陕西西安710071

出　　处：《航天医学与医学工程》2002年第5期366-368,共3页Space Medicine & Medical Engineering

摘　　要：目的探求可应用于航天和航空领域的有效自适应噪声抵消算法。方法设计变步长的最小均方算法 (LMS算法 )实现自适应噪声抵消。通过估计输入信号信噪比确定迭代步长 ,从而自动调节自适应滤波器参数 ,直至获得被干扰语音的最优估计。结果当输入的含噪语音信噪比为 - 6dB、0dB、6dB时 ,降噪后输出信噪比分别为 1 8.2dB、2 2 .1dB和 2 5 .2dB。结论该算法性能优于归一化LMS算法 ,可为今后自适应噪声抵消技术在航天和航空领域的应用提供依据。Objective To study a modified Least Mear Square(LMS) algorithm that can be applied in aerospace and aviation fields. Method A modified LMS algorithm was proposed and step size was calculated by estimated signal noise ratio(SNR) of input signal. Parameters of filter were adjusted automatically until optimal estimation of disturbed speech was obtained. Result Output SNR of estimated speech was increased respectively to 18.2 dB,22.1 dB and 25.2 dB, when input SNR of disturbed speech was -6 dB,0 dB,6 dB. Conclusion The performance of the modified algorithm has obvious advantages over that of NLMS algorithm.The results may be advantageous to related application of adaptive noise canceller (ANC )in aerospace and aviation fields.

关 键 词：自适应噪声抵消器 变步长 LMS算法 信噪比 

分 类 号：R852.8[医药卫生—航空、航天与航海医学]