A Novel Distributed Brillouin Sensor Based on Optical Differential Parametric Amplification

We propose and demonstrate a novel distributed sensor based on coherent interaction of the Brillouin gain and loss via optical differential parametric amplification (ODPA), which provides narrowed parametric Brillouin gain spectrum, strong Brillouin signal via differential gain, and short measurement time simultaneously. In experiment, a 0.5 m spatial resolution with a strain accuracy of 6 με is realized by using 20/15 ns Stokes and anti-Stokes pulse pair in a 15 m polarization-maintaining fiber. The spectrum narrowing phenomenon in ODPA Brillouin sensor is discussed.