DEVICE FOR DETERMINING DEGREE AND PLACE OF DISTURBANCE OF ZONE FIBRE-OPTIC SYSTEM FOR PROTECTING OBJECTS Russian patent published in 2025 - IPC G08B13/186 G01N21/84 

FIELD: optics.

SUBSTANCE: invention relates to fibre-optic interferometry and can be used in equipment, which enables to detect intrusion into a protected circuit, for example, to warn about overcoming barriers of industrial enterprises. Device for determining the degree and place of disturbance of a zone fibre-optic system for protecting objects contains a laser with a fibre-optic output, which includes a circuit for tuning radiation frequency according to a sawtooth law and outputs of the beginning and the end of this adjustment, a multi-position object splitter, different-arm fibre-optic interferometers, units for recording an interference signal and digital signal processing units. Since the device as a whole is interferometric, all fibre-optic components are single-mode. Fiber-optic output of the laser is connected to the input of the object branch, its outputs, the number of which is equal to the number of zones, are connected to the inputs of different-arm fiber-optic interferometers, outputs of which are connected to inputs of interference signal recording units, in turn, outputs of units are connected to inputs of digital signal processing units, besides, inputs of the beginning and end of laser radiation frequency tuning of units are connected to corresponding outputs of the unit.

EFFECT: wider range of possible values of lengths of perimeter zones towards small values, increased noise immunity of the system and easier repair of a sensitive cable.

4 cl, 5 dwg