Brillouin optical correlation domain analysis system with kilometer measurement range based on intensity modulation scheme

摘要

We report a novel method to enhance the performance of Brillouin optical correlation domain analysis (BOCDA) system based on intensity modulation of light source. In addition to the former sinusoidal frequency modulation of the BOCDA, we newly applied a synchronous intensity modulation, which changed the output power spectrum and the shape of the background noise in local Brillouin gain spectrum, together. We could observe the noise suppression of more than 40% with this implementation, and effectively enlarge the measurement range of the system. For the first time, a distributed measurement over 1-km range is successfully demonstrated using the BOCDA system with a decent spatial resolution of 30 cm.