Brillouin optical time domain analysis enhanced by tailored pump compensation

Brillouin optical time domain analysis (BOTDA) enhanced by the tailored compensation for the propagation loss of a pump pulse is experimentally demonstrated for long-distance and high-resolution distributed sensing. Distributed Brillouin amplification (DBA) of the pump pulse is applied in addition to an ordinary BOTDA configuration, where the frequency modulation with time-dependent amplitude variation is introduced to the DBA pump for tailored compensation for the propagation loss. In experiments, the distribution map of the Brillouin frequency along a 51.2 km test fiber is measured with a spatial resolution of 50 cm and a measurement error (σ) of less than 1 MHz.