Abstract

Distributed optical fiber sensors using Brillouin scattering have already demonstrated their ability to measure changes in strain and temperature over long distance. However, the simultaneous sensitivity of the Brillouin scattering to these two parameters is a real disadvantage during the instrumentation and monitoring of structures, such as for civil engineering, oil industry applications (i.e. instrumentation of pipelines or wells) or electrical power cables monitoring. In this article, we present a new instrument enabling independently measurement of temperature or strain using a unique fiber in a single measurement. This method, which we will call B-OTDR DSTS for “Distributed Strain and Temperature Sensing”, is based on the measurement of frequency (as a standard BOTDR) but also intensity of Brillouin scattering. However, as the measurement of the latter requires an accurate measurement of power levels along the fiber, it is necessary to correct the losses by a Rayleigh OTDR measurement. The architecture of the BOTDR-DSTS allows simultaneous measurement of the Brillouin and Rayleigh backscatters. We will detail the validation results of this new device and show the interest of such a measurement on the instrumentation of a cable into a 2 km deep observation well.

Hybrid B-OTDR/Φ-OTDR for multi-parameter measurement from a single end of fiber

Xiao Zhou, Feng Wang, Zhen Liu, Yanqing Lu, Chengyu Yang, Yixin Zhang, Liyang Shao, and Xuping Zhang
Opt. Express 30(16) 29117-29127 (2022)

Single-shot distributed temperature and strain tracking using direct detection phase-sensitive OTDR with chirped pulses

J. Pastor-Graells, H. F. Martins, A. Garcia-Ruiz, S. Martin-Lopez, and M. Gonzalez-Herraez
Opt. Express 24(12) 13121-13133 (2016)

Distributed strain and temperature sensing over 100 km using tunable-wavelength OTDR based on MEMS filters

M. A. Taranov, B. G. Gorshkov, A. E. Alekseev, and V. T. Potapov
Appl. Opt. 60(11) 3049-3054 (2021)

Hybrid Brillouin/Rayleigh sensor for multiparameter measurements in optical fibers

A. Coscetta, E. Catalano, E. Cerri, N. Cennamo, L. Zeni, and A. Minardo
Opt. Express 29(15) 24025-24031 (2021)

Study on the simultaneous distributed measurement of temperature and strain based on Brillouin scattering in dispersion-shifted fiber

Liwen Sheng, Ligong Li, Lei Liu, Leijun Hu, Ming Yuan, and Jisong Yan
OSA Continuum 3(8) 2078-2085 (2020)