小波与傅里叶变换耦合的静电监测信号去噪法  

Static Monitoring Signal De-noising by Wavelet and FFT

作　　者：钱颖雪[1] 左洪福[1] 李耀华[1] 

机构地区：[1]南京航空航天大学民航学院,江苏南京210016

出　　处：《计算机技术与发展》2009年第7期1-3,9,共4页Computer Technology and Development

基　　金：国家"863"计划(2006AA04Z427);国家自然基金委员会与中国民用航空总局联合资助项目(60672164)

摘　　要：针对航空发动机气路静电监测信号微弱、背景噪声大、信噪比低、信号特征难以提取的问题,根据傅里叶变换和小波阈值降噪理论,提出了小波分解与傅里叶变换耦合的滤波法,并与常规的陷波器消噪法、小波阈值消噪法进行了对比研究。模拟实验结果显示小波分解与傅里叶变换耦合法的滤波效果明显优于其他两种方法,将该方法用于发动机气路模拟实验采集的监测信号处理,结果表明:小波分解与傅里叶变换耦合的滤波法适合对航空发动机模拟气路静电监测信号做滤波处理,可以用来提取异常信号发生的位置。Aero- engine gas path monitoring signal was characteristic in weak amplitude, strong noise, low SNR and was difficult to extract. In order to solve these problems, wavelet transform and FFT filter was constructed and compared with conventional methods like the notch filter and the wavelet threshold de- noising. The simulation results showed that wavelet transform and FFT filter can de- noise signal more efficiently than others. Finally used the method in aero- engine gas path simulation experiment and concluded： wavelet trans- form and FFT filter can be used to extract the sharp edge and process the monitoring signal of aero- engine gas path system.

关 键 词：航空发动机 静电监测 降噪 小波变换 信噪比 

分 类 号：TN911.7[电子电信—通信与信息系统]