Abstract: Disclosed is a method for reconstructing an electromagnetic vector wave backscattered in all or part of an optical fiber. According to an embodiment of the method a light signal of a frequency v0 or v0+vA is injected into the optical fiber. A step of polarization-resolved heterodyne optical detection includes the generation of at least two orthogonally polarized backscattered light signals, producing a beat preferably of a frequency vA. At least one photodetector converts the orthogonally polarized backscattered light signals into initial analog signals. Electrical homodyne detection is performed by an IQ demodulator so as to generate I and Q demodulated analog signals. A processing module reconstructs the electromagnetic vector wave backscattered in all or part of the optical fiber.
Type:
Grant
Filed:
July 26, 2020
Date of Patent:
August 15, 2023
Assignee:
Febus Optics
Inventors:
Gaƫtan Calbris, Vincent Lanticq, Etienne Almoric
Abstract: The invention relates to a method for digitally processing a signal from an optoelectronic distributed measuring device based on Brillouin scattering, said device comprising a continuous light source (1), a coupler (2), an acousto-optic modulator (3), an optical fiber (5) to be tested so that it emits in return a signal by spontaneous Brillouin backscattering at a frequency ?F equal to ?p??Bz, where ?Bz is the Brillouin frequency to be measured at every point z of said optical fiber (5), a local oscillator (16) emitting another light signal intended to be mixed with said return signal emitted by Brillouin backscattering by said optical fiber (5) to be tested, a detection module (9) able to detect said Brillouin shift frequency ?Bz at every point z of said optical fiber and a processing module for linking this Brillouin shift frequency ?Bz at every point z of said optical fiber to a temperature value and a strain value.