04598275 is referenced by 228 patents and cites 4 patents.

A proximity monitoring system for individually identifying an object or person, and having a central information processor, and a signal receiver, several remote detectors in various locations at a distance from the information processor, each having a first transmitter for communicating with such processor and having a second transmitter and a receiver, and several individual personalized portable identifiers, each identifier having a continuously activated receiver, a signal transmitter which is normally de-activated, a battery pack, and a switch operated by the receiver in response to a signal from a detector, to switch the battery on to activate the transmitter, for emitting a personalized coded identification signal.

Title
Movement monitor
Application Number
6/492669
Publication Number
4598275
Application Date
May 9, 1983
Publication Date
July 1, 1986
Inventor
Ralph P Devoy
Scarborough
CA
Clive Ross
Downsview
CA
Agent
George A Rolston
Assignee
Marc Industries Incorporated
CA
IPC
G08B 23/00
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