An improved Savitzky-Golay filtering algorithm for measuring pharmaceutical vial's oxygen content based on wavelength modulation spectroscopy

摘要

An improved Savitzky-Golay filtering algorithm was adopted to denoise the on-line measurement of a pharmaceutical vial's oxygen content based on wavelength modulation spectroscopy. This algorithm was created to feed second harmonic signals containing noise into a sliding window and to reduce, or eliminate, pulse interference. Then, the data containing no singular values were processed by weighted moving average filter. The second harmonic signals were simulated and the experiments performed to measure a pharmaceutical vial's oxygen concentration by using the improved Savitzky-Golay filtering algorithm: results were compared with those from a traditional algorithm, and a wavelet transform filter. The results indicated that the improved Savitzky-Golay filtering algorithm can match the efficacy of the wavelet analysis, but the former ran much faster than the latter, and the system response time was about 300 ms. The improved Savitzky-Golay filtering algorithm was suitable for on-line measurement of gas concentration.