Distributed optical fiber disturbance positioning system based on the asymmetric dual Mach-Zehnder interference, and positioning method thereof
US10365126B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2016 |
| Grant date | Jul 30, 2019 |
| Priority date | — |
| Expiry date | Oct 27, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/186
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A distributed optical fiber disturbance positioning system based on the asymmetric dual Mach-Zehnder interference, unlike traditional dual Mach-Zehnder distributed optical fiber disturbance sensing system, the present invention adopts two narrow-bandwidth optical sources (1a, 1b) and adopts corresponding DWDM (3a, 3b) before the detector (4a, 4b) to filter the backscatter noise of the optical fiber, and can solve the problems of having too low SNR due to backscatter influence when the sensing distance is long. The present invention also provides a positioning method for applying the system, which obtains the TFD of the disturbance frame signals by using the time-frequency analysis method based on the short-term average frequency, and takes the points near the point of maximum frequency as the effective signal segment for performing cross-correlation time delay estimation, thus obtaining the delay, and the disturbance position. The method of the invention positions the asymmetric disturbance frame signals in the systems, thus having a high positioning accuracy and reliability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.