Abstract：An experimental study on denoising of ozone concentration signal measured by differential absorption spectroscopy was presented. Common denoising methods are wavelet transform, Savitzky-Golay filtering and Fourier transform filtering. Firstly, the three kinds of filtering methods were used to denoise the absorption spectra of ozone respectively, and the absorption spectra after denoising were obtained. It was found that the wavelet transform and Savitzky-Golay filter can fit the feature absorption well, and the Fourier transform filter was slightly worse. Then, the obtained spectrum was analyzed and evaluated by using the signal-to-noise ratio and the root mean square error. The experimental results showed that Savitzky-Golay filtering has the best effect on signal denoising and can be applied preferentially to the spectrometric analysis of ozone.
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2020, Vol. 41 
