US 9,810,556 B2
Apparatus for measuring optical signals from multiple optical fiber sensors
François Ouellette, Stanstead (CA)
Filed by François Ouellette, Stanstead (CA)
Filed on Apr. 2, 2015, as Appl. No. 14/677,470.
Claims priority of provisional application 61/973,975, filed on Apr. 2, 2014.
Prior Publication US 2015/0285683 A1, Oct. 8, 2015
Int. Cl. G01D 5/353 (2006.01); G01J 3/02 (2006.01); G01J 3/45 (2006.01); G01J 3/18 (2006.01)
CPC G01D 5/35354 (2013.01) [G01D 5/35383 (2013.01); G01J 3/0218 (2013.01); G01J 3/45 (2013.01); G01J 3/1895 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A sensor apparatus comprising:
an interrogator comprising light sources, each one of the light sources emitting pulses having either a first respective wavelength or a second respective wavelength about a respective average wavelength of the each one of the light sources; and
FBG sensor arrays, each one of the FBG sensor arrays corresponding to one of the light sources and comprising a plurality of FBG sensors on an optical fiber and being for reflecting the pulses,
wherein FBG sensors of a given FBG sensor array have a spatial separation therebetween which is sufficient to allow, at a receiver, a temporal discrimination between reflected pulses produced by each one of the FBG sensors of a given FBG sensor array;wherein each one of the FBG sensor arrays has a respective spectral reflection window having a reflection spectrum with sides, the respective spectral reflection window comprising the respective average wavelength of the corresponding one of the light sources, wherein the first respective wavelength and the second respective wavelength have a difference substantially smaller than the spectral width of the FBG sensors that allows both the first respective wavelength and the second respective wavelength to be on a same side of the reflection spectrum;wherein the respective average wavelengths of the light sources have a spectral separation therebetween which is sufficient to allow, at the receiver, a spectral discrimination between reflected pulses from each one of the FBG sensor arrays.