Page 107 - 应用声学2019年第2期

第 38 卷 第 2 期 Vol. 38, No. 2
2019 年 3 月 Journal of Applied Acoustics March, 2019

⋄ 研究报告 ⋄

一种改进的非整数自适应时延估计方法 ∗

李均浩 1 刘文红 1,2†

(1 上海电机学院电气学院 上海 201306)
(2 上海电机学院电子信息学院 上海 201306)

摘要 针对基于时延估计的机电设备故障声定位中的低信噪比和脉冲噪声情况，用 α 稳定分布建模噪声，改
进了非整数自适应时延估计方法。共变相关法对观测序列进行时延估计粗测，将得到的估计值作为非整数自
适应时延估计器的初值；将共变相关法中共变序列作为时延估计器的输入信号，在最小平均 p 范数准则下迭代
得到非整数时延估计值。共变序列保留了原始序列间的时延信息，削弱了不相关的噪声。计算机仿真对比实
验验证了改进的方法在脉冲环境和低信噪比条件下有更好的性能。
关键词 设备声故障定位，α 稳定分布，共变，互相关法，非整数时延估计
中图法分类号: TN911.7 文献标识码: A 文章编号: 1000-310X(2019)02-0253-08
DOI: 10.11684/j.issn.1000-310X.2019.02.015

An improved fractional adaptive time delay estimation method

LI Junhao 1 LIU Wenhong 1,2

(1 School of Electronic Engineering, Shanghai Dianji University, Shanghai 201306, China)
(2 School of Electronics and Information, Shanghai Dianji University, Shanghai 201306, China)

Abstract Fractional adaptive time delay estimation (TDE) method, modeling noise with α stable distri-
bution, is improved to adapt low signal to noise ratio (SNR) and impulse noise in equipment fault acoustic
localization based on TDE. Covariate correlation method gets integer part of TDE, it is used as initial value of
adaptive delay estimator. Covariant sequence is used as input of time delay estimator, finally, fractional TDE
value is obtained by iteration under minimum average p norm criterion. Covariant sequence preserves time
delay information between original sequences, weakens irrelevant noise. Computer simulations and comparative
experiments verify that improved method has better performance under impulse environment and low SNR.
Key words Equipment acoustic fault location, α stable distribution, Covariation, Cross correlation method,
Fractional time delay estimation

2018-05-28 收稿; 2018-09-04 定稿
国家自然科学基金项目 (61172108), 上海电机学院横向科研合作项目 (17B56)
∗
作者简介: 李均浩 (1993- ), 男, 河南南阳人, 硕士研究生, 研究方向: 风电设备状态监测与故障诊断。
† 通讯作者 E-mail: liuwenhong@sdju.edu.cn