Brillouin Optical Time Domain Reflectometry (BOTDR) is a technology used in distributed fiber optic sensing. It is a technique that allows the measurement of strain or temperature variations along a fiber optic cable. The Brillouin effect, named after Léon Brillouin, is a phenomenon in which light interacting with a sound wave in a material undergoes a frequency shift. In the context of BOTDR, this interaction occurs in an optical fiber.


Multi-parameter distributed fiber sensing with higherorder optical and acoustic modes

We propose a novel multi-parameter sensing technique based on a Brillouin optical time domain reflectometry in the elliptical-core few-mode fiber, using higher-order optical and acoustic modes. Multiple Brillouin peaks are observed for the backscattering of both the LP01 mode and LP11 mode. We characterize the temperature and strain coefficients for various optical–acoustic mode pairs. By selecting the proper combination of modes pairs, the performance of multi-parameter sensing can be optimized. Distributed sensing of temperature and strain is demonstrated over a 0.5-km elliptical-core few-mode fiber, with the discriminative uncertainty of 0.28°C and 5.81 ?? for temperature and strain, respectively.

Distributed Temperature and Strain Sensing Using Brillouin Optical Time Domain Reflectometry Over a Few Mode Elliptical Core Optical Fiber

We propose a single-ended Brillouin-based sensor in elliptical-core few-mode optical fiber for multi-parameter measurement using spontaneous Brillouin scattering. Distributed sensing of temperature and strain is demonstrated over 0.5 km elliptical-core few-mode fiber.