METHOD AND SYSTEM FOR INTERROGATING OPTICAL FIBERS

• Main Authors: FERNÁNDEZ RUIZ, María del Rosario, GONZÁLEZ HERRÁEZ, Miguel, PRECIADO GARBAYO, Javier, VILLAFRANCA VELASCO, Asier, FIDALGO MARTINS, Hugo, MARTÍN LÓPEZ, Sonia, SORIANO AMAT, Miguel
• Format: Patent
• Language: English
• Published: 25.11.2021
• Subjects: COLORIMETRY; MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT,POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRA-RED,VISIBLE OR ULTRA-VIOLET LIGHT; MEASURING; PHYSICS; RADIATION PYROMETRY; TESTING; TESTING STATIC OR DYNAMIC BALANCE OF MACHINES ORSTRUCTURES; TESTING STRUCTURES OR APPARATUS NOT OTHERWISE PROVIDED FOR

A method and a system for interrogating an optical fiber includes a probe signal that has a first frequency comb at a first repetition rate (Δf) injected into the optical fiber. A backscattering signal that includes the probe signal convolved with an impulse response of the optical fiber in reflection which is sensitive to at least one parameter being measured from the optical fiber is gathered. The backscattering signal is beaten with a local oscillator signal to generate a beating signal, the local oscillator signal including a second frequency comb at a second repetition rate that is offset from the first repetition rate (Δf+δf) and being mutually coherent with the first frequency comb. The resulting beating signal is analysed to thereby determine the at least one parameter being measured from the optical fiber.