METHOD OF DETECTING INTRUDER IN CONTROLLED ZONE Russian patent published in 2012 - IPC G08B13/00 G01S13/36 

FIELD: physics.

SUBSTANCE: in the method, duration of the irradiating radio pulse, transmission band of transmission and reception channels are selected such that duration of the received radio signal does not exceed the delay time of the signal reflected from the intruder on the boundary of the controlled zone relative the direct signal received with minimum delay. Since the size of the sensitivity zone is standardised and can vary, the method employs formation of several embedded sensitivity zones of different sizes to monitor movement of the intruder with defined direction of movement of the intruder. Division of the frequency band of the probing signal into several frequency channels increases electromagnetic noise-immunity.

EFFECT: high noise-immunity of detection owing to reduced fuzziness and instability of boundaries of the detection zone and standardisation of its size to eliminate false response to movement of objects and bodies outside the detection zone, which is relevant for metre and decimetre waves when using weakly directional antennae, when the sensitivity zone is not limited by the beam pattern.

7 cl, 13 dwg