Systematic-error suppression in low-coherence Brillouin optical correlation-domain reflectometry

Sci Rep. 2023 Oct 16;13(1):17531. doi: 10.1038/s41598-023-44801-4.

Abstract

Brillouin optical correlation-domain analysis (BOCDA) utilizing low-coherence light sources offers high-resolution distributed strain and temperature sensing. However, conventional BOCDA requires dual-end injection of pump and probe light into the sensing fiber. To overcome this limitation, low-coherence Brillouin optical correlation-domain reflectometry (BOCDR) based on spontaneous Brillouin scattering has emerged, enabling single-end light injection. While a pilot demonstration has shown a spatial resolution of 19 cm, a comparison of its measurement accuracy with standard BOCDR systems is yet to be explored. This study presents a distributed measurement with ~ 3 cm spatial resolution and demonstrates that low-coherence BOCDR eliminates systematic errors caused by direct sinusoidal modulation, offering enhanced measurement precision.