The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 27, 2001
Filed:
May. 19, 1999
Michael G. Ressl, Western Springs, IL (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
The invention provides for assessing location and/or proximity to a buried or submerged optical fiber cable. A seismic generator creates seismic pulses, at known frequencies, on the ground (or water) at a first location and the synchronous rotation of the polarization state of light transmitted through the optical fiber cable is detected. Other seismic pulses are generated at different locations and the polarization rotation is detected at each such location to locate a closest proximity to the cable, corresponding to a minimum or maximum of polarization rotation. A wireless synchronous signal is generated with the seismic pulses to differentially isolate the polarization rotation signal; and, if desired, to further determine distance between the cable and the source of the seismic pulse.