Simultaneous Strain and Temperature Measurement Based on Chaotic Brillouin Optical Correlation-Domain Analysis in Large-Effective-Area Fibers

Chaotic Brillouin optical correlation domain analysis (BOCDA) has been proposed and experimentally demonstrated with the advantage of high spatial resolution. However, it faces the same issue of the temperature and strain cross-sensitivity. In this paper, the simultaneous measurement of temperature and strain can be preliminarily achieved by analyzing the two Brillouin frequencies of the chaotic laser in a large-effective-area fiber (LEAF). A temperature resolution of 1 °C and a strain resolution of 20 µε can be obtained with a spatial resolution of 3.9 cm. The actual temperature and strain measurement errors are 0.37 °C and 10 µε, respectively, which are within the maximum measurement errors.