基于压缩传感的EMI信号处理  

EMI signal processing via compressive sensing

作　　者：屠海滨[1] 陈伟球[2] 金贤玉[1] 

机构地区：[1]浙江大学土木工程学系,浙江杭州310058 [2]浙江大学工程力学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2012年第11期2007-2012,共6页Journal of Zhejiang University：Engineering Science

基　　金：国家"973"研究发展计划资助项目(2009CB623200);国家自然科学基金资助项目(50838008)

摘　　要：针对目前结构健康监测系统由于采集数据量过大而造成的信号传输与存储效率低下的问题,提出将压缩传感(CS)用于机电阻抗(EMI)信号的压缩,以实现EMI信号的高效传输和储存.文中用匹配追踪(MP)分析EMI信号的稀疏度,并把高斯随机矩阵作为观测矩阵,同时满足了压缩传感所要求的信号的稀疏性和观测矩阵的不相干性.以一维损伤杆的EMI分析为例,把均方差作为损伤指标,讨论压缩传感的压缩效果和抗噪声能力.结果表明,使用压缩传感之后,传输带宽和储存空间只需为原来的28%;在观测为4倍稀疏度情况下,100次试验都能够对不同损伤进行有效识别;当信噪比大于20dB时,观测值能稳定地重构出原始信号.证实压缩传感作为一种信号处理方法可以应用于EMI系统信号处理.Taking account of the inefficiency in data transmission and storage caused by the enormous data collected during structural health monitoring（SHM）,the compressive sensing（CS） technique was employed in data compression of the electromechanical impedance（EMI） signal in order to achieve efficient data transmission and storage.In this paper,the sparsity of EMI signal was analyzed by matching pursuit（MP）,and the Gauss random matrix was taken as the measurement matrix,thus both the sparsity of the signal and the incoherence of the measurement matrix,as required by the CS,were met simultaneously.As an example,an one-dimensional damaged bar was used to perform the EMI analysis,in which the data compression efficiency and the noise resistance ability of CS were discussed by taking the root mean square deviation（RMSD） as the damage index.The research results indicate that,after the intervention of CS,the transmission bandwidth and storage space are only 28% of the original signal.The damage of 100 different trials can all be identified if the measurement number is four times of the sparsity.And when the signal-to-noise rate（SNR） is greater than 20dB,the original signal can be reconstructed stably from the CS results.The research results prove that,as a data processing method,CS can be applied in the EMI data processing.

关 键 词：机电阻抗法 信号处理 压缩传感 抗噪声 

分 类 号：TU311[建筑科学—结构工程]