Position monitoring system and method

Abstract

A monitoring system and method, particularly applicable to vehicle monitoring, detects theft of a vehicle or other object and automatically transmits its current position to the proper authorities. For vehicle monitoring, a vehicle monitoring unit mounted on the vehicle determines the initial position of the vehicle and thereafter periodically determines the current position of the vehicle via a position detector. Preferably, the position detector consists of a satellite receiver, such as a GPS receiver, for receiving satellite signals from a plurality of satellites. A controller circuit determines the position of the vehicle from the satellite signals. A range of movement of the vehicle is then determined by comparing the initial position and the current position. When the detected range equals or exceeds a selected range limit, the controller circuit activates a transmitter which transmits position signals representative of the current position of the vehicle. The range limit may be permanently set during manufacture of the unit or may be selectable by an operator. The position signals are received by a remote dispatch center which relays the position of the vehicle to appropriate law enforcement officials or a security service.