Measurement Accuracy Improvement of Brillouin Signal Using Wavelet Denoising Method

The signals measured from the Brillouin Optical Time Domain Analysis (BOTDR), distributed optical fiber sensing system is generally prone to contamination by environmental factors, which may degrade the measurement accuracy in field applications, a suitable method of correcting this degradation is desired. In this paper, the wavelet signal processing method is presented to filter out the noise in measured signals and validated with the strain data taken from a smart BOTDA-based cable. The results show that this method can effectively denoise the information of the measured strain of the smart cable and improve the precision of the cable force. The maximum error between the control cable force and the average cable force are 8.8% and 5.1%, respectively, prior to and after noise filtering. This comparison shows that the wavelet denoising method is suitable for the measured signal obtained from the Brillouin optical sensing system.