The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 08, 2022
Filed:
Jul. 11, 2019
Optasense Holdings Limited, Farnborough, GB;
Sara Carver, Farnborough, GB;
Andrew Weld, Farnborough, GB;
Optasense Holdings Limited, Hampshire, GB;
Abstract
This application described methods and apparatus for distributed fibre optic sensing. A sensing apparatus has a modulator which modulates radiation from an optical source to interrogate a sensing optical fibre with a first interrogation pulse at a first frequency (F) and a second interrogation pulse at a second, different, frequency (F), both different in frequency from a local oscillator (LO). A mixer mixes backscatter from the sensing optical fibre with the local oscillator and supplies the mixed signal to a detector that provides a corresponding digital signal. A processor processes the digital signal (DX, DY) in a first and second processing channels to demodulate respective first and second phase signals based on the respective frequency difference between the first and second frequency and the local oscillator and determines a temporal difference between the first and second phase signals.