05363425 is referenced by 268 patents and cites 12 patents.

A system for providing a personal location, access control and asset tracking service using an in-building telephone network is disclosed. In a first embodiment, users of ID badges containing an RF transmitter can be located across the telephone network for receiving incoming calls. Receiver units in or near telephone sets instruct the system of the identity of the user located near the telephone set. In another embodiment, access to a building or rooms therein is controlled according to the identity of the ID badge wearer. Similar receiver units located at building and room entrances receive the RF transmission from the ID badge to allow or deny access to the rooms or building. In a third embodiment, ID tags placed on material assets permit the system user to monitor the movement and location of specific material assets associated with that ID tag. The ID tag also contains an RF transmitter which is used to transmit an RF burst to receiver units located across the telephone network.

Title
Method and apparatus for providing a personal locator, access control and asset tracking service using an in-building telephone network
Application Number
7/906192
Publication Number
5363425
Application Date
June 29, 1992
Publication Date
November 8, 1994
Inventor
Michael J Wakim
Nepean
CA
Adrian M G Yip
Kanata
CA
Peter P K Soong
Nepean
CA
Robert G Samuel
Nepean
CA
Sohale A Mufti
Kanata
CA
Agent
Jean Pierre Fortin
Assignee
Northern Telecom
CA
IPC
H04M 11/00
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