04742357 is referenced by 224 patents and cites 12 patents.

A stolen object location system having a base station, a location network and an object unit which is associated with the object to be located. The location system is capable of operating in a plurality of different location modes ranging from simple triangulation to LORAN. The base station, upon being notified that the object has been stolen, will transmit a locate request message to the object unit specifying the location mode to be used and the transmission frequency of the object unit's transmitter. An electronic control in the object unit will control the operation of the object unit's receiver and transmitter in accordance with the location mode and transmission frequency specified in the locate request message. The electronic control will also initiate the transmission of an alarm message if the object unit loses communication with the base station, and is capable of transmitting a tattle-tale message, effectively relaying the alarm message of another object unit if the base station does not respond to the other object unit's alarm message.

Title
Stolen object location system
Application Number
6/908156
Publication Number
4742357
Application Date
September 17, 1986
Publication Date
May 3, 1988
Inventor
Ernie C Rackley
1704 Rockfield, Troy, 48098
MI, US
Agent
Remy J VanOphem
James R Ignatowski
IPC
G01S 3/02
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