Patent ID: 9739645
Date: 2017-08-22
CPC Classifications: G01D

Claim:
1. A method of distributed sensing comprising the steps of: interrogating an optical fiber with electromagnetic radiation; detecting electromagnetic radiation which is back-scattered from the optical fiber; processing said detected back-scattered radiation to provide a measurement signal for each of a plurality of longitudinal sensing portions of the optical fiber; and analysing the measurement signals from the longitudinal sensing portions to detect events of interest, wherein the method comprises analysing the measurement signals of a first subset of longitudinal sensing portions to provide a first zone having a first sensing function and analysing the measurement signals of at least a second subset of longitudinal sensing portions to provide at least a second zone having a second, different, sensing function, wherein the measurement signals from the first zone are analysed to determine if the measurement signals match a first characteristic or signature of a first event of interest and the measurement signals from the second zone are analyzed to determine if the measurement signals match a second characteristic or signature of a second, different, event of interest.