US 5,418,537 A · Location of missing vehicles

Abstract

Method and apparatus for determining the present location of a missing vehicle, such as an automobile or marine vessel, using a Global Positioning System that receives GPS signals from two or more GPS satellites. A GPS antenna, GPS signal receiver/processor, a paging responder, a cellular telephone and associated antenna, and a controller/modem are installed in a vehicle and electrically connected together. When the vehicle is determined to be missing, because the vehicle has been misplaced, lost or stolen, the vehicle owner or operator contacts a vehicle location service center, which broadcasts a paging request that is received by the paging responder on the vehicle. The paging responder causes the controller/modem to interrogate the GPS receiver/processor to determine the present location of the vehicle. The receiver/processor determines the present vehicle location and notifies the controller/modem of such location. The controller/modem then causes the cellular telephone to notify the vehicle location service center of the present location of the missing vehicle so that the vehicle can be recovered. The GPS signal receiver/processor and GPS antenna can be replaced by a receiver/processor and associated antenna that works with a LORAN system, or with a group of gyroscopes or local magnetic field sensors mounted on the vehicle. Optionally, the signal receiver/processor is kept in a "sleeper" mode to conserve power, until the controller/modem receives a paging request for its present location. Optionally, the receiver/processor is periodically activated to determine, and thus update, its present location. Optionally, the presence of the GPS antenna and/or the cellular telephone antenna on the vehicle is concealed. In another embodiment, a sensor is positioned on the vehicle, and the cellular telephone is caused to transmit to the vehicle location center a message containing information on the present location of the vehicle when the sensor senses occurrence of a selected trigger event, such as unauthorized movement of, or breaking into, the vehicle.

Claims27

Dependent claims

Apparatus for determining the present location of a missing vehicle, the apparatus comprising:

a GPS signal antenna and receiver/processor, connected to the antenna, attached to a vehicle, to receive and process GPS signals to determine the present location of the vehicle to which the antenna and receiver/processor are attached;
an event sensor that determines when a selected trigger event involving the vehicle has occurred and issuing a sensor output signal when that event occurs;
controller means, connected to the GPS receiver/processor and to the event sensor, for receiving the event sensor output signal and, in response thereto, for issuing a first output signal that is received by the GPS receiver/processor that commands the receiver/processor to determine and issue as an output signal the present location of the receiver/processor, and for receiving the receiver/processor output signal representing present location of the receiver/processor and issuing this present location information as a second output signal;
a cellular telephone, connected to the controller means, for receiving the controller means second output signal and, in response thereto, for transmitting the controller means second output signal to a selected telephone number;
and
a power supply to deliver electrical power to at least one of the receiver/processor, the event sensor, the controller means and the cellular transmitter,
where the receiver/processor, the event sensor, the controller means, and the cellular telephone are all carried on the vehicle whose present location is to be determined.

4 more elements