Patent ID: 8947232
Filing Date: 2015-02-03
Classification: G01H,G08B

Abstract:
1. An intrusion detection system for monitoring a premises comprising: an optical cable that extends about the premises and has a first end opposite a second end, the optical cable comprising an optical fiber having a first end opposite a second end; and a highly coherent optical time domain reflectometry means, operably coupled to the first end and the second end of the optical cable, comprising: a highly coherent optical source to generate a first optical signal to launch into the first end of the optical fiber at a first wavelength and a second optical signal to launch into the second end of the optical fiber at a second wavelength different than the first wavelength; and signal processing circuitry that analyzes a first backscatter signal and a second backscatter signal received via the first end and the second end, respectively, of the optical fiber in response to the first launched optical signal and the second launched optical signal, respectively, in order to detect an intrusion of the premises, wherein the first and second backscatter signals in the optical fiber are affected by an acoustic wave or pressure incident on the optical cable caused by the intrusion of the premises.