Features of Digital Filters in Raman DTS

The efficiency of digital filters in signal processing from a distributed fiber optic sensor (DTS) is evaluated. Improvement of the metrological characteristics of DTS is possible either by improving hardware or the signal processing algorithm. As a rule, the first issue requires large financial investments. Digital filters can significantly improve the characteristics of DTS as a result of noise reduction in optoelectronic conversion. The Butterworth, Chebyshev, Bessel, Savitzky-Golay, Median, and Wavelet filters were compared. The evaluation criteria are the average absolute error and the standard deviation of the error. The standard deviation must be used to detect a situation when signal fluctuations appear after filtering. Chebyshev filter and Wavelet filtering turned out to be the most effective. Recommendations for the use of digital filters and limitations of methods are given.