Analytic technology of infrared absorption spectrum based on time-frequency analysis

摘要

Infrared absorption spectroscopy has been widely used in the field of quantitative analysis. The overlapped spectral lines of different components makes the component recognition and concentration calculation of the mixture difficult to realize. In order to solve this problem, in this paper the analytic technology of infrared absorption spectrum has been researched to establish an effective, accurate and stable component identification method. The derivative spectrum of direct absorption spectral line is calculated to eliminate the influence of background and noise. The wavelet analysis method with appropriate wavelet basis and scale resolution is used to make the time-frequency analysis of the derivative spectrum to obtain the two dimensional time-frequency characteristics matrix. The correlation analysis in both time and frequency dimensions to the time-frequency characteristics matrix of different components and mixtures is researched to realize the component identification in combination with the morphological characteristics of the derivative spectral line. Experimental results show that the proposed method can effectively identify the target component from the mixture spectral line. The research provides a method and technical route for simultaneous detection and spectral analysis of multi-component.