06300875 is referenced by 141 patents and cites 11 patents.

A system for communicating the location of an object, the system including a transmitter, the transmitter being capable of communicating using any one of a plurality of possible non-switched communications networks; a GPS receiver coupled to the transmitter, the GPS receiver being configured to providing data representing position of the GPS receiver, such that the data generated by the GPS receiver can be transmitted by the transmitter; a common housing supporting the transmitter and the GPS receiver to define a portable package; and a monitoring device remote from the portable package, the transmitter being configured to transmit communications to the monitoring device via a non-switched wireless network without need for human intervention in initiating a call from either the transponder or the monitoring device.

Title
Method and apparatus for high efficiency position information reporting
Application Number
9/444859
Publication Number
6300875 (B1)
Application Date
November 22, 1999
Publication Date
October 9, 2001
Inventor
Robert W Schafer
Parker
TX, US
Assignee
MCI WorldCom
MS, US
IPC
G08B 23/00
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