Reduction of measurement time in BOTDA sensors using wavelet shrinkage

A new method based on wavelet shrinkage is presented showing decreased measurement time for Brillouin optical timedomain analysis (BOTDA) sensors. In BOTDA sensors the data acquired from measurements is contaminated with multiple sources of noise requiring enhancement in order to extract the Brillouin gain spectrum (BGS) and find strain and temperature. Conventional BOTDA sensors have used the very slow ensemble averaging technique which requires hundreds of acquisitions of each time-domain waveform. In this paper, we enhance time-domain waveforms using wavelet shrinkage before applying the ensemble averaging on them. This modification yields a significant reduction of 95% in the number of waveform acquisitions. Experimental results confirm the accuracy of the measurement based on wavelet shrinkage and show that the proposed sensor has one of the shortest measurement times amongst BOTDA sensors.