05742233 is referenced by 444 patents and cites 33 patents.

A signaling system comprises a portable signaling unit, a remote alarm switch device, a central dispatch station, and a wireless communication system such as a cellular or telephone system, etc., and a GPS or alike system. The portable signaling unit and the remote alarm switch may be adapted to be worn at different locations on the person's body. The remote alarm switch may be concealed in the form of a wristband or in the form of any other object such as a broach, pendant, or keychain. When the person in distress activates the remote alarm switch or when the remote alarm switch is removed from the individual by a forceful or unauthorized action or when the signaling unit is removed from the proximity of the remote alarm switch, the portable signaling unit sends a data transmission which includes its location to the central dispatch station. The portable signaling unit also has manual alarm trigger capabilities so it can be used without the remote alarm switch unit. The central dispatch station receives the data transmission and accurately displays the user identification, stored personal information, nature of the alarm; in addition the location of the portable signaling unit is superimposed on a digitized map at a position corresponding to the location of the person wearing the portable signaling unit. The portable signaling unit can be remotely activated from a central dispatch station to determine and monitor the location of the portable signaling unit.

Title
Personal security and tracking system
Application Number
8/786411
Publication Number
5742233
Application Date
January 21, 1997
Publication Date
April 21, 1998
Inventor
David G Doe
Walpole
MA, US
Ann Hoffman
Stoughton
MA, US
Judd A Hoffman
Medfield
MA, US
Mark S Hoffman
Medfield
MA, US
Agent
Timothy J Shea II
Assignee
Hoffman Resources
MA, US
IPC
G08B 23/00
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