Abstract: A system and method for defeating a Relay Station Attack on a hands-free anti-theft system of a vehicle. The hands-free anti-theft system includes a vehicle-mounted transceiver which transmits an authentication request and a hands-free key transceiver paired therewith which receives the authentication request and responds thereto by transmitting a reply signal causing the vehicle to unlock and/or start. A detector is provided having a receiver operating on the frequency at which the authentication request is transmitted, and a memory in which a known characteristic of the authentication request signal is stored. The key transceiver and the detector are located beyond an activation range of the authentication request. When the detector receives a signal, it compares a characteristic of a received signal with the known characteristic, and triggers an alarm signal if there is a match.

Abstract: A system and method for defeating a Relay Station Attack on a hands-free anti-theft system of a vehicle. The hands-free anti-theft system includes a vehicle-mounted transceiver which transmits an authentication request and a hands-free key transceiver paired therewith which receives the authentication request and responds thereto by transmitting a reply signal causing the vehicle to unlock and/or start. A detector is provided having a receiver operating on the frequency at which the authentication request is transmitted, and a memory in which a known characteristic of the authentication request signal is stored. The key transceiver and the detector are located beyond an activation range of the authentication request. When the detector receives a signal, it compares a characteristic of a received signal with the known characteristic, and triggers an alarm signal if there is a match.