Expansion of spatial measurement range in a correlation based Brillouin optical sensing system

Abstract

We propose a novel technique for expansion of spatial measurement range in a Brillouin optical correlation domain analysis (BOCDA) sensor system. Unlike conventional BOCDA, which has only a single correlation peak within the sensing fiber, the proposed scheme has multiple correlation peaks within the sensing section, and enables us to obtain selectively the physical information at a position corresponding to each correlation peak since the fiber under test consists of different kinds of fibers with different Brillouin frequency shifts. Using the proposed technique, we have successfully expanded a measurement range while maintaining the spatial resolution.