Methods and apparatus for Distributed Optical Fiber Sensing of Strain or Multiple Parameters
Patent, Filed 30 Jan 97, patented 26 May 98
DEPARTMENT OF THE NAVY WASHINGTON DC
Pagination or Media Count:
A distributed optical fiber sensor system including a patterned array of weakly reflecting broadband gratings or other sensors serially disposed along a common fiber. The laser sources are multiplexed onto the fiber and are propagated through a directional coupler toward the sensors. The return signals are directed by the directional coupler to a demultiplexer that separates the signals by center frequencies and sends each to a respective detector. All reflection signals generated by a single input pulse of a given wavelength are detected prior to the input coupling of the next input pulse of that wavelength, the input pulse repetition period being T greater than or equal Nto, N being the number of grating sensors and to being their spacing or separation in optical propagation time.
- Optical Detection and Detectors
- Fiber Optics and Integrated Optics