Patent ID: 9410903
Filing Date: 2016-08-09
CPC Classification: G01N

Claim Text:
1. A method for estimating a parameter, the method comprising: transmitting a control signal to a coherent optical source, the coherent optical source configured to emit an optical signal having a central wavelength, the control signal configured to chaotically vary a wavelength of the optical source and generate a chaotically excited optical signal, wherein chaotically varying the wavelength introduces noise and decreases the coherence of the optical signal, and chaotically varying the wavelength includes periodically applying a random wavelength change relative to the central wavelength, each wavelength change correlated with a different sensing location; modulating the optical signal via an oscillating modulation signal having a time-varying modulation frequency; transmitting the optical signal from the optical source into an optical fiber, the optical fiber including at least one sensing location; receiving a reflected signal including light reflected from the at least one sensing location; and determining the modulation frequency and an instantaneous wavelength of the reflected signal, correlating the modulation frequency and the instantaneous wavelength with a sensing location, and estimating a value of the parameter at the sensing location based on at least the instantaneous wavelength.