Method and apparatus for active tamper indicating device using optical time-domain reflectometry

Patent · Tue Dec 14 04:00:00 EST 1999

OSTI ID:20013895

Smith, D B; Muhs, J D; Pickett, C A; Earl, D D

An optical time-domain reflectometer (OTDR) launches pulses of light into a link or a system of multiplexed links and records the waveform of pulses reflected by the seals in the link(s). If a seal is opened, the link of cables will become a discontinuous transmitter of the light pulses and the OTDR can immediately detect that a seal has been opened. By analyzing the waveform, the OTDR can also quickly determine which seal(s) were opened. In this way the invention functions as a system of active seals. The invention is intended for applications that require long-term surveillance of a large number of closures. It provides immediate tamper detection, allows for periodic access to secured closures, and can be configured for many different distributions of closures. It can monitor closures in indoor and outdoor locations and it can monitor containers or groups of containers located many kilometers apart.

• Sponsoring Organization: US Department of Energy
• OSTI ID: 20013895
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
DESIGN
OPTICAL SYSTEMS
REFLECTIVITY
SECURITY SEALS
VISIBLE RADIATION