Data Processing in the Distributed Strain Measurement of BOTDR Based on Wavelet Analysis

摘要

Strain distribution of the structure is used to detect the damage and assess the conditions of the structure. A Brilliouin optical time domain reflectometer(BOTDR) is an innovative distributed measure technique based on Brilliouin scattering, which can monitor the strain distribution of the structure by measuring the strain along the optical fiber bound on or inside the structure. In this paper a data processing method based on the wavelet analysis is introduced. The denoising and detection of singularity points of the measured data can be performed using the wavelet analysis that includes the following steps: (1) the averaging of three successive measurements; (2) smoothing the strain data; (3) separating the temperature information; (4) detecting the singularity points. Finally, a case is taken from the monitoring data of an ongoing tunnel engineering to demonstrate the method effective and powerful.