基于变分模态分解的超声检测信号降噪研究  

Study on ultrasonic detection signal denosing based on variational mode decomposition

作　　者：王大为 王召巴[1] 李鹏[3] 陈友兴[1] 李海洋[1] WANG Dawei;WANG Zhaoba;LI Peng;CHEN Youxing;LI Haiyang(School of Information and Communication Engineering,North University of China,Taiyuan 030051,China;College of Physics and Information Engineering,Shanxi Normal University,Linfen 041000,China;Xi’an Modern Chemistry Research Institute,Xi’an 710065,China)

机构地区：[1]中北大学信息与通信工程学院,山西太原030051 [2]山西师范大学物理与信息工程学院,山西临汾041000 [3]西安近代化学研究所,陕西西安710065

出　　处：《中国测试》2019年第12期106-111,共6页China Measurement & Test

基　　金：国家自然科学基金(11604304);山西省科技攻关项目(201603D121006-1);山西省自然科学基金(201701D221127,201801D121150);山西省回国留学人员科研资助项目(2016-084);山西省高等学校科技创新项目(201657)

摘　　要：为解决超声检测信号的降噪问题,该文基于变分模态分解能将信号分解为一系列窄带模式,而高斯噪声则被分解为整个频带内若干个宽带模式,提出一种超声检测信号降噪方法。该方法通过变分模态分解,计算各模态带宽和中心频率,选择信号模态,根据信号模态重构无噪信号4步实现对超声检测信号的降噪;通过仿真实验表明该文方法可以将含噪超声信号分解为信号模态和噪声模态,去除噪声模态后可显著提升信噪比;对信噪比为10 dB的含噪信号经该文方法处理后得到的重构信号和原始无噪信号的均方误差为0.0007,波形相似系数为0.9940,重构信噪比为19.2374 dB。此外,为提高超声信号仿真模型和实际测量到的超声信号的匹配度,该文提出一种改进的超声信号模型。实验表明该模型和实测超声信号更接近,其均方误差为0.0083,波形相似度为0.9733。To solve the problem of noise reduction of ultrasonic detection signal,a novel method of noise reduction for ultrasonic detection signal based on variational mode decomposition was proposed in this paper.The proposed method was introduced in four parts:variational mode decomposition,calculation of the bandwidth and center frequency of each mode,signal mode selection and reconstruction of noise-free signal according to signal mode.The simulation results showed that the proposed method could decompose the noisy ultrasonic signal into signal mode and noise mode,and the signal-to-noise ratio could be significantly improved after removing the noise mode.For example,this method was employed to process noisy signal with signal-tonoise ratio of 10 dB,and the mean square error(MSE),normalized correlation coefficient(NCC)and reconstructed signal-to-noise ratio(ESNR)of reconstructed signal and original noise-free signal were 0.0007,0.9940 and 19.2374 respectively.Additionally,an improved ultrasonic signal model was proposed in order to enhance the similarity between the simulation model of ultrasonic signal and the measured ultrasonic signal.The experiment results showed that compared with the exponential model,the proposed model could better simulate the measured ultrasonic signal,with a with a mean square error of 0.0083 and normalized correlation coefficient of 0.9733.

关 键 词：无损检测 超声信号降噪 变分模态分解 超声信号仿真模型 

分 类 号：TN912[电子电信—通信与信息系统]