Abstract: A method for providing a combined theft detection and proximity detection system is disclosed. The method comprises the step of providing a vehicle unit having a transmitter and a receiver to transmit and receive an RF signal such that a user of the vehicle unit can inform other vehicle units of presence of the vehicle unit, and can be informed of the presence of other such vehicle units by detecting the RF signal emitted by the other vehicle units located in the range. The receiver further provides an alarm signal to warn of this presence. The method also comprises the step of providing a portable unit adapted to receive the RF signal from the vehicle unit to inform a driver that his vehicle is no longer in range.

Abstract: An object of the present invention is to provide a method of proximity detection based on transmitting at random intervals burst of a RF signal at a power level, and receiving, while not transmitting, a received RF signal. When detecting said received RF signal emitted by a target in range; an alarm signal is provided to warn of the proximity of the target. Another broad aspect of the invention is to deploy the above method among members of a territory and provide a monitoring patrol to verify if the proximity of those members can be detected from their RF signal. Another broad aspect of the invention is to provide to those members a plurality of status from which each member selects one corresponding to its current status and to transmit that status in the RF signal he is transmitting, thereby informing other members in range of his current status and enabling them to evaluate the potential danger associated with him.

Abstract: An object of the present invention is to provide a method of proximity detection based on transmitting at random intervals burst of a RF signal at a power level, and receiving, while not transmitting, a received RF signal. When detecting said received RF signal emitted by a target in range; an alarm signal is provided to warn of the proximity of the target. Another broad aspect of the invention is to deploy the above method among members of a territory and provide a monitoring patrol to verify if the proximity of those members can be detected from their RF signal. Another broad aspect of the invention is to provide to those members a plurality of status from which each member selects one corresponding to its current status and to transmit that status in the RF signal he is transmitting, thereby informing other members in range of his current status and enabling them to evaluate the potential danger associated with him.