葡萄糖溶液光声信号时域与频域特性对比  

Characteristics comparison of photoacoustic signal of glucose solution in time domain and frequency domain

作　　者：王倩 吕鹏飞 何巧芝 吕娜 赵辉[1] WANG Qian;LÜPeng-fei;HE Qiao-zhi;LÜNa;ZHAO Hui(Department of Instrument Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China)

机构地区：[1]上海交通大学仪器科学与工程系,上海200240

出　　处：《光学精密工程》2020年第11期2421-2428,共8页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.61873168)。

摘　　要：为了克服时域信号易受环境干扰影响的缺陷,提高液体浓度光声测量的稳定性,在已有的光声信号时域峰峰值特性研究的基础上,对光声信号的频域特性展开研究。分别讨论了葡萄糖溶液光声信号的功率谱特性和最大熵谱特性,并分别采用峰值检测、对数拟合等方法对光声信号的频谱特性进行分析。对比了葡萄糖光声信号时域峰峰值与功率谱、最大熵谱的非线性误差和重复性误差。实验结果表明对最大熵谱曲线进行对数拟合之后采用截距表征光声信号的方法,其非线性误差和重复性误差相比于传统的时域峰峰值检测方法分别减小了28%和71%。由此可以得出频域分析方法可以显著减小葡萄糖浓度检测的非线性误差和重复性误差,提高无创血糖浓度检测的精度与稳定性。To overcome the shortcomings of the time-domain signal,which is easily affected by environmental interference,and improve the stability of photoacoustic measurements of the liquid concentrations,this study investigated the frequency-domain characteristics of a photoacoustic signal based on the time-domain peak-to-peak characteristics of the photoacoustic signal.The power spectrum characteristics and maximum entropy spectrum characteristics of the photoacoustic signal of glucose solution were evaluated.Different methods,such as peak detection and logarithmic fitting,were used to analyze the spectral characteristics of the photoacoustic signal.The nonlinear error and repeatability error of the time-domain peak detection,power spectrum,and maximum entropy spectrum methods were compared.The experimental results show that by using the intercept to characterize the photoacoustic signal after the logarithmic fitting of the maximum entropy spectrum curve,the nonlinear error and repeatability error can be reduced by 28%and 71%,respectively,compared with the traditional time-domain peak-to-peak detection method.The frequency-domain method can be used to reduce the nonlinear and repeatability errors of glucose concentration detection significantly.Furthermore,the frequency-domain method could improve the accuracy and stability of noninvasive blood glucose concentration detection.

关 键 词：光声测量 血糖浓度 光声信号 时域 频域 功率谱 最大熵谱 

分 类 号：TH773[机械工程—仪器科学与技术] R318.6[机械工程—精密仪器及机械]