Optical waveguides – Optical waveguide sensor – Including physical deformation or movement of waveguide
Patent
1999-03-17
2000-11-14
Sanghavi, Hemang
Optical waveguides
Optical waveguide sensor
Including physical deformation or movement of waveguide
25022715, 356 511, G02B 600
Patent
active
061481238
ABSTRACT:
The optical distance along a buried optical fiber (12) from a particular location (13) therealong to a central facility (10) is measured by first applying an intentional stress to the fiber in the form of a vibration signal (35) transmitted into the ground. A timing signal (36) is transmitted to the central facility (10) in synchronism with the application of the stress. Using the timing signal as a reference, the central facility can determine the time difference between when the stress was applied, and when the central facility detected the stress. From the time difference, and a knowledge of the propagation rate of the timing signal, the central facility can establish the optical distance to the particular location at which the stress was applied.
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Eslambolchi Hossein
Huffman John Sinclair
AT&T Corp
Levy Robert B.
Sanghavi Hemang
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