05621411 is referenced by 105 patents and cites 12 patents.

A method of determining the exact location of a transponder with respect to a reader antenna, with no additional components to the existing system required, is disclosed. An existing pin of the reader IC, the RSTP pin, provides an analog fieldstrength signal from which the distance to the reader antenna is deduced via known in the art signal processing methods. A grid or even an exact position location along a route is also achievable with initial set-up of at least two transponders a predetermined distance apart and a reader antenna.

Title
Positioning with RF-ID transponders
Application Number
130966
Publication Number
5621411
Application Date
June 20, 1996
Publication Date
April 15, 1997
Inventor
Kostantin Aslanidis
Dachau
DE
Horst Mollik
Offenberg
DE
Andreas Hagl
Dachau
DE
Agent
Richard L Donaldson
James C Kesterson
Rebecca A Mapstone
Assignee
Texas Instruments Incorporated
TX, US
IPC
G01S 13/84
G01S 13/75
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