Hybrid distributed acoustic testing

• Main Authors: Ashry, Islam, Alias, Mohd Sharizal Bin, Ooi, Boon Siew, Hveding, Frode, Yuan, Mao, Arsalan, Muhammad
• Format: Patent
• Language: English
• Published: 28.12.2021
• Subjects: ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVEREDIN A SINGLE OTHER SUBCLASS; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC ORINFRASONIC WAVES; MEASURING; MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR; MEASURING QUANTITY OF HEAT; MEASURING TEMPERATURE; PHYSICS; TARIFF METERING APPARATUS; TESTING; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR

The subject matter of this specification can be embodied in, among other things, a method that includes separating, from a few mode optical fiber, a collection of backscattered Rayleigh signals based on a vibration of the few mode optical fiber at a vibration frequency at a first location along the few mode optical fiber, separating, from the few mode optical fiber, a collection of backscattered Stokes Raman signals and Anti-Stokes Raman signals based on a temperature of the few mode optical fiber at a second location along the few mode optical fiber, detecting the separated Rayleigh signals and Raman signals, determining, based on detecting the collection of backscattered Rayleigh traces, at least one of the first location, the vibration frequency, and an amplitude of the vibration, and determining, based on the detecting the collection of backscattered Raman signals, the temperature at the second location.