Back to results
US 7,030,974 B2Granted
Alarm condition distributed fiber optic sensor with storage transmission-reflection analyzer
AssigneesCentro de Investigacion Cientifica y de Educacion Superior de Ensenada, Centro de Investigaciones en Materiales Avanzados, S.C.
InventorsVasilii V. Spirin, Mikhail G. Shlyagin, Serguei V. Miridonov, Francisco J. Mendieta Jimenez, Alfredo Márquez Lucero, Enrique Mitrani Abenchuchan
Life of this patent
Estimating the term…
Abstract
This invention pertains to alarm condition fiber optic sensor with storage transmission-reflection analyzer for detection and localization of any number of consecutive loss-inducing disturbances along the test fiber.
Claims10
A distributed fiber optic sensor comprising:
- a test fiber having a first port and a second port;
- a light source for producing a beam of light propagating along the test fiber;
- a fiber optic beamsplitter having a first port connected to the light source, a second port connected to the first port of the test fiber, and a third and a fourth port;
- a plurality of reflectors with distance-depending differential reflectivity positioned along the test fiber and a plurality of loss-inducing members positioned along the test fiber, wherein said each of the reflectors is matched to each loss-inducing members, wherein at least one reflector is placed between each consecutive loss-inducing members;
- an optical reflection detector for detecting a light flux, the optical reflection detector connected to the third port of optic beamsplitter, wherein the reflection detector is adapted to sense changes in the average power of the light reflected from the reflectors;
- an optical transmission detector adapted to receive the light flux, connected to the second port of test fiber, said transmission detector being operable to sense changes in the average power of the light transmitted through the test fiber;
- and
- a storage transmission-reflection analyzer connected to reflection and transmission detectors and adapted to measure time-behavior of a transmission-reflection dependencies of test fiber, said analyzer being operable to identify locations and values of any number of consecutive loss-inducing disturbances along the test fiber by using a stored locations and values of previous perturbations and the slope of dependence of normalized reflected average power versus the square of normalized transmitted average power for current loss-inducing perturbation.
5 more elements
A method for calculating the value and location of a disturbance in a system, the method comprising the steps of:
- positioning an optical fiber sensor along the system to be monitored;
- wherein the optical fiber sensor comprises:
- a test fiber having a first port and a second port;
- a light source for producing a beam of light propagating along the test fiber;
- a fiber optic beamsplitter having a first port connected to the light source, a second port connected to the first port of the test fiber, and a third and a fourth port;
- a plurality of reflectors positioned along the test fiber and a plurality of loss-inducing members positioned along the test fiber, wherein each of the reflectors is matched to each of the loss-inducing members, wherein at least one reflector is placed between each consecutive loss-inducing members;
- an optical reflection detector for detecting a light flux, the optical reflection detector connected to the third port of optic beamsplitter, wherein the reflection detector is adapted to sense changes in the power of the light reflected from the reflectors;
- an optical transmission detector adapted to receive the light flux, connected to the second port of test fiber, said transmission detector being operable to sense changes in the average power of the light transmitted through the test fiber;
- and
- a transmission-reflection analyzer connected to reflection and transmission detectors, said analyzer adapted to measure and store transmission-reflection dependencies of test fiber, said analyzer being operable to identify the locations and values of any number of consecutive loss-inducing disturbances along the test fiber by using a stored locations and values of previous perturbations and the slope of dependence of normalized reflected average power versus the square of normalized transmitted average power for current loss-inducing perturbation.
- measuring and storing transmission-reflection dependencies of test fiber;
- and
- identifying the locations and values of any number of consecutive loss-inducing disturbances along the test fiber by using a stored locations and values of previous perturbations and the slope of dependence of normalized reflected average power versus the square of normalized transmitted average power for current loss-inducing perturbation.
10 more elements
Dependencies are inferred from the claim text.