Patent · US Expired

Intrusion detection system for use on single mode optical fiber using a storage register for data

US7142737B1 · kind B1 · utility

20Cited by
11References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 15, 2005
Grant dateNov 28, 2006
Priority date
Expiry dateJun 15, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B6/2766
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A telecommunications optical fiber is secured against intrusion by detecting manipulation of the optical fiber prior to an intrusion event. This can be used in a non-locating system where the detection end is opposite the transmit end or in a locating system which uses Fresnel reflections and Rayleigh backscattering to the transmit end to detect and then locate the motion. The Rayleigh backscattering time sliced data can be stored in a register until an intrusion event is detected. The detection is carried out by a polarization detection system which includes an optical splitter which is manufactured in simplified form for economic construction. This uses a non-calibrated splitter and less than all four of the Stokes parameters. It can use a polarimeter type function limited to linear and circular polarization or two linear polarizers at 90 degrees.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.