为了提高动态光谱(dynamic spectrum, DS)数据处理方法的效率与精度, 采用单拍提取技术, 即对所采集全部波长对应的光电容积脉搏波(photoelectric plethysmography, PPG)叠加平均所得到的全波段PPG, 以单个脉搏为周期, 提取其上升沿作为模板； 用该模板校正各个波长PPG的上升沿, 再以此计算吸光度的差分值, 进而得到单拍DS； 然后根据3σ准则, 剔除其中含有粗大误差的单拍DS, 对剩余单拍DS进行叠加平均, 作为最终输出的DS。 测量10名志愿者的数据, 与频域提取法的处理结果进行对比: 同一个体同一手指DS相关系数离差平方和由0.006 775改善到0.000 384 0； 同一个体不同手指DS相关系数离差平方和由0.013 93改善到0.002 205, 而不同个体DS之间的差异性有明显增加。 结果表明, 单拍提取技术可以更快地得到高质量的DS数据, 加速了DS进入实际应用的进程。

To improve the efficiency and accuracy of the dynamic spectrum data processing, the method of single-trial estimation was adopted. First, the rising edge of the whole band PPG was extracted, which was calculated by averaging superimposed collected photoelectric plethysmography (PPG) at all wavelengths as a template per single pulse; Second, this template was used to correct the rising edge of PPG at all wavelengths, and the difference of absorbance was calculate, and then a single-trial DS was obtained; finally, the single-trial DS which contained the gross error under the 3σ criterion was removed, and then the remaining superimposed single-trial DS was averaged as the final output of the DS. Data measured from 10 volunteers were compared with the results of the extraction in frequency domain: the correlation coefficient distribution of the DS from the same finger of the same individual was improved from 0.006 775 to 0.000 384 0; the correlation coefficient distribution of the DS from the different fingers of the same individual was improved from 0.013 93 to 0.002 205, whereas the differences of DS between different individuals were significantly increased. The results show that the method of single-trial estimation can get the DS data more quickly with high quality, and accelerate the process of DS put into practical application.