Patent ID: 8208767

Claim:
An apparatus for estimating a parameter at distributed locations, the apparatus comprising: an optical fiber comprising: a first series of fiber Bragg gratings (FBGs) configured to measure the parameter at a portion of the distributed locations, each FBG in the first series having a first nominal reflection wavelength; a second series of FBGs configured to measure the parameter at another portion of the distributed locations, each FBG in the second series having a second nominal wavelength; and an optical interrogator configured to illuminate the optical fiber and to receive light signals resulting from the illumination, the light signals comprising first light signals from the first series of FBGs within a first range of wavelengths, second light signals from the second series of FBGs within a second range of wavelengths, and other light signals within a third range of wavelengths, the ranges of wavelengths being distinct from each other; wherein the first light signals and the second light signals are used to estimate the parameter at the distributed locations.