基于小波变换的激光外差干涉微裂缝信号解调算法  

Laser Heterodyne Interference Micro-Crack Signal Demodulation Algorithm Based on Wavelet Transform

作　　者：付巍 朱岩 张鹏 柴艳丽 FU Wei;ZHU Yan;ZHANG Peng;CHAI Yanli(School of Electrical and Control Engineering,North University of China,Taiyuan 030051,China;Aviation Industry Corporation of China,Changcheng Institute of Metrology ＆ Measurement,Beijing 100095,China)

机构地区：[1]中北大学电气与控制工程学院,山西太原030051 [2]中国航空工业集团公司北京长城计量测试技术研究所,北京100095

出　　处：《测试技术学报》2018年第5期369-373,共5页Journal of Test and Measurement Technology

基　　金：航空科学基金资助项目(2016ZD44006)

摘　　要：为了解调出带有裂缝信息的微弱超声信号,提高激光外差干涉法探测材料表面裂缝的能力,研究了利用小波变换实现激光外差干涉微裂缝信号的相位解调算法,并将小波变换算法运用到实验获得的零差信号,提取出超声信号,得到了被测样件裂缝的位置信息.实验结果表明:利用小波变换算法得到的被测样件裂缝的距离与实际距离的误差率为2.40%,验证了算法的可行性和准确性.In order to demodulate weak ultrasonic signal with micro-crack information and enhance the ability of laser heterodyne interferometry to detect the surface micro-crack,a discussion on the phase demodulation algorithm using the wavelet transform for laser heterodyne interference micro-crack signal was presented.The homodyne signal was obtained from the experiment by using the wavelet transform algorithm,meanwhile the ultrasonic signal was extracted and the position information of the micro-crack was obtained.The experimental results show that the error rate of the distance between the actual distance and the distance of the micro-crack obtained by the wavelet transform algorithm is 2.40%,which verifies the feasibility and accuracy of the algorithm.

关 键 词：光外差干涉 微裂缝 小波变换 相位解调 

分 类 号：TN247[电子电信—物理电子学]