For intrusion detection, OptaSense uses a distributed acoustic sensing setup that analyzes the Rayleigh scattering from a standard single-mode telecommunications fiber (or any existing installed fiber) using an interferometric optical time-domain reflector configuration. The strain signature of a fiber-optic cable around 50 km long can be deconvolved to detect movement at distances of around 10 m from the fiber with a 1 m accuracy. Cheaper to implement than a wall, easier to physically hide, and allowing the natural passage of territorial animals, a fiber-optic border fence.
'Build the wall' with fiber optics
Laser Focus World January 21, 2019
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