基于循环统计量的幅值解调方法及应用  

Demodulation Analysis Based on the Cyclic Statistics and Its Application

作　　者：何俊[1] 陈进[1] 毕果[1] 周福昌[1] 

机构地区：[1]上海交通大学振动冲击噪声国家重点实验室

出　　处：《汕头大学学报（自然科学版）》2007年第1期66-71,共6页Journal of Shantou University：Natural Science Edition

基　　金：国家自然科学基金资助项目(No:50175068)

摘　　要：基于循环平稳基本理论,提出一种新的时变调幅信号处理方法.利用循环自相关函数切片对加性白噪声的自然免疫力,取信号特定循环频率处的循环自相关函数切片,可以提高信号的信噪比.当结合其他的解调方法对切片信号进行解调分析时,能够大大提高解调分析方法的抗噪能力.仿真和实验信号分析结果表明方法的有效性.Demodulation analysis is an important technique in the fault diagnosis of rotating machine with rolling elements and gears. However, its efficiency is badly influenced by the background noise, so the usage of these methods is restricted widely in engineering practice. In this paper, a new demodulation method is proposed based on the cyclostationarity. The Cyclic Autocorrelation Function（CAF） is an important second-order cyclic statistics and acts as an efficient parameter to the demodulated analysis. According to this method, the modulation information can be obtained through demodulation analysis of the slice of CAF at special cyclic frequency. Results from the analysis of the simulated signals and experimental data demonstrate that the new method has higher antinoise ability than ordinary methods.

关 键 词：故障诊断 解调分析 循环平稳 循环自相关函数 

分 类 号：TP206[自动化与计算机技术—检测技术与自动化装置] TP911[自动化与计算机技术—控制科学与工程]