Laser & Optoelectronics Progress, Volume. 56, Issue 19, 193004(2019)
Spectral Absorption Line-Shape Fitting Algorithm of Gaseous Molecule Based on Cavity Ring-Down Spectroscopy
For the spectral absorption curve of cavity ring-down spectroscopy (CRDS), this study uses the MATLAB software and the least-squares algorithm to program six different line-shape fitting algorithms (VP, GP, AVP, AGP, SDVP, and SDAVP algorithms) commonly used for gas absorption spectroscopy and designs interface windows for the parameter setting and fitting result display. The absorption spectrum of the carbon dioxide gas with known concentration is obtained using CRDS. The six aforementioned algorithms are used to fit the absorption spectrum, and the fitting residuals of six different line-shape fitting algorithms are compared. The fitting results denote that the fitting curve is almost coincident with the measuring points. The average AVP residual is the largest, which is 3.1748×10 -3, whereas GP and AGP denote the minimum average residual of 1.3212×10 -3. This study verifies the feasibility of the six aforementioned line-shape fitting algorithms with respect to the fitting of gas absorption spectrum. The AVP's operation time is the shortest(i.e., 1.7516 s), whereas the SDAVP's operation time is the longest (i.e., 389.682 s). The GP's operation time is less than that of AGP. Therefore, the GP is most suitable for performing the CRDS spectral line-shape fitting with respect to the residuals and operation time.
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Suxia Xing, Si Chen, Ruimin Guo, Wenchao Cui, Hewei Dong. Spectral Absorption Line-Shape Fitting Algorithm of Gaseous Molecule Based on Cavity Ring-Down Spectroscopy[J]. Laser & Optoelectronics Progress, 2019, 56(19): 193004
Category: Spectroscopy
Received: Mar. 4, 2019
Accepted: Apr. 22, 2019
Published Online: Oct. 23, 2019
The Author Email: Guo Ruimin (guorm@nim.ac.cn)