STOLEN CAR DETECTION SYSTEM Russian patent published in 1997 - IPC

FIELD: transport engineering; car antitheft systems. SUBSTANCE: to improve probability of detection of stolen car and accelerate its location information on car characteristics (licence plate No, color and type of body), car distance from check station and bearing are represented on display 18 at control station (patrol service station or traffic control station). Car characteristics are formed in encoder 7 into coded signal and radiated through broadband signal modulator 8 and high frequency generator 9 to check point. Antenna 11, in search mode, after reception of coded signal and processing the signal in high frequency amplifier 13, frequency detector 14, low frequency amplifier 15, amplitude detector 16 and decoder 17, is changed over into tracking mode by signal from clock pulse generator 19 applied to corresponding receiving part of antenna. Signal supplied to display 18 gives information on car bearing. Signal on car characteristics is re-radiated to car through frequency transmitter 20, power amplifier 21 and transmitting antenna 22 of check point and, after processing in high frequency amplifier 2 and frequency detector 3, is multiplied in correlator 4 with signal from output of modulator 8. Voltage across correlator output corresponds to distance of car from check point. This voltage signal is used to operate actuating unit 5 which shuts down the engine and initiates emergency signalling. After digitization in analog-to-digital converter 6, distance range signal, as well as car characteristics signal is transmitted to display 18. EFFECT: facilitated finding of stolen car. 2 dwg