基于S变换的自适应降噪方法

本资料包含pdf文件1个，下载需要1积分

Adaptive noise reduction method based OH S transformLI Xing-hui ，ZHANG Guang-ming ，YIN Jun-xia ，LI Wei-ql-，WU Zhong-an(1.Department of Mechanical and Electronic Engineering，Sichuan Engineering Technical Colege，De yang 618000，Chinal 2.MechanicalDe sign Institute，No.6 Engineering Coporation Limited of CRllG，Xiangyang 441003，China)Abstract：The time-frequency characteristics was brief introduced and a new adaptive noise reductionmethod was presented based on S transform.Employing the high-quality time-frequency distribution ofS transform，an time-frequency filter was designed on the time-frequency plane for extraction of signalcomponent from unstable signal，showing that this method could be used to obtain a satisfactory effect inrespect of noise restraint of the signal and improvement of signal-to-noise ratio.The simulative test of thesignal model and fault diagnosis of gears in gear-box manifested the result of the restraint of the noise andthe extraction of the signal with this method，and the signal-to-noise ratio was improved tO a larger extent。

The result showed that this method could be used tO extract effectively the fault feature of the gears and e-liminate the influence of the false components，SO that the accuracy of fault diagnosis of the gears was im-proved。

Key words：S transform；fault diagnosis；de-noising；time-frequency filter齿轮箱传动机构是机械设备中最常用的传动机构，它被广泛地应用于各类机械设备的运动和动力传递中.由于设备所处的环境复杂，故障特征往往被噪声淹没，难以准确判断其故障，需要采用有效的时频分析信号处理方法分离和提取.作为-种在短时傅里叶变换(STFT)和小波变换基础上发展起来的新时频分析方法，S变换已开始用来分析振动信号，如地震[ 引、机械工程[3-4]、雷达[ 等领域，并取得-定的研究成果。

近年来，多数专家学者基本是根据瞬时频率的收稿 日期：2012-06-27作者简介：李兴慧(19830，女，河南通许人，助教统计特征，确定滤波器带宽的，但这些方法都将能量较小的信号滤去而保留较强的信号，容易出现截波现象.本文结合文献E7]的小波降噪方法，并根据 S变换后有效信号和噪声信号在时频平面上的分布特征，构造了时频滤波器，用它对含高斯白噪声的非平稳信号进行滤波，以达到突出有效信号和压制噪声的效果，