Application of EEMD combined with cross-correlation algorithm in Doppler flow signal  

基于EEMD互相关算法在多普勒流量信号中的应用

作　　者：SHI Fengdong GONG Ruishi LIANG Tongtong LÜDong 史风栋;巩瑞士;梁通通;吕东(天津工业大学控制科学与工程学院,天津300387;天津工业大学工程训练国家级实验教学示范中心,天津300387;天津腾领电子科技有限公司,天津300393)

机构地区：[1]School of Control Science and Engineering,Tiangong University,Tianjin 300387,China [2]National Demonstration Center for Experimental Engineering Training Education,Tiangong University,Tianjin 300387,China [3]Tianjin Tenlink Electronic Technology Co.,Ltd.,Tianjin 300393,China

出　　处：《Journal of Measurement Science and Instrumentation》2025年第1期58-65,共8页测试科学与仪器(英文版)

基　　金：supported by National Natural Science Foundation of China(No.61973234);Tianjin Science and Technology Plan Project(No.22YDTPJC00090)。

摘　　要：To address the issue of low measurement accuracy caused by noise interference in the acquisition of low fluid flow rate signals with ultrasonic Doppler flow meters,a novel signal processing algorithm that combines ensemble empirical mode decomposition(EEMD)and cross-correlation algorithm was proposed.Firstly,a fast Fourier transform(FFT)spectrum analysis was utilized to ascertain the frequency range of the signal.Secondly,data acquisition was conducted at an appropriate sampling frequency,and the acquired Doppler flow rate signal was then decomposed into a series of intrinsic mode functions(IMFs)by EEMD.Subsequently,these decomposed IMFs were recombined based on their energy entropy,and then the noise of the recombined Doppler flow rate signal was removed by cross-correlation filtering.Finally,an ideal ultrasonic Doppler flow rate signal was extracted.Simulation and experimental verification show that the proposed Doppler flow signal processing method can effectively enhance the signal-to-noise ratio(SNR)and extend the lower limit of measurement of the ultrasonic Doppler flow meter.针对超声多普勒流量计在低流速信号采集中易受噪声干扰而导致测量精度不高的问题,提出了一种集合经验模态分解(Ensemble empirical mode decomposition,EEMD)结合互相关的信号处理算法。首先,利用快速傅里叶变换(Fast Fourier transform,FFT)频谱分析确定信号的频率范围。其次,以一定频率进行数据采集,将采集到的多普勒流速信号应用EEMD算法进行分解,得到一系列本征模态函数(Intrinsic mode functions,IMFs)。最后,结合能量熵对IMFs进行重组,并对重组后的流速信号进行互相关降噪处理,以提取理想的超声多普勒流速信号。仿真和实验结果表明,采用EEMD结合互相关算法可有效提高多普勒流量信号的信噪比,并扩展超声多普勒流量计的测量下限。

关 键 词：ultrasonic Doppler flow meter ensemble empirical mode decomposition(EEMD) CROSS-CORRELATION fast Fourier transform(FFT)spectrum analysis energy entropy 

分 类 号：TN9[电子电信—信息与通信工程]