FIBER-OPTIC SENSOR OF THE OBJECT PERIMETER PROTECTION SYSTEM

Abstract

An analysis of the existing fiber-optic sensors of the system for detecting unauthorized entry into the territory of a protected facility was carried out. It is noted that an attractive feature of such sensors is immunity to electromagnetic radiation and electrical safety. As a result of the analysis, it was concluded that the well-known fiber optic sensors alone can detect only the fact of unauthorized entry, and with a multizone security system – both the fact and the zone of unauthorized entry, but not the reason for the operation of the fiber optic sensor, i.e. parameter of the offending object (small animal, person or vehicle). To expand the functionality, a fiber-optic sensor has been developed that allows you to determine not only the fact of penetration, but also the parameters of the intruder object, namely its mass.An optical fiber was chosen for the developed fiber-optic sensor and an optical fiber macrobend shaper with the highest susceptibility to macrobend – G 655. It was found that an increase in the length of the macrobend arc at a constant macrobend shaper radius leads to an increase in the attenuation of the optical radiation signal in the optical fiber. It is indicated that this dependence is close to linear in the range of macrobending arc lengths from zero to pR.