05602538 is referenced by 160 patents and cites 16 patents.

Apparatus and method of identifying a plurality of transponders (10-16) entering into an inquiry field (18) of an interrogation unit (20) are provided. The transponders (10-16) are each assigned a unique identification code. Upon receipt of an interrogation pulse from the interrogation unit (20), each transponder (10-16) responds with its respective identification code. Depending on the spatial distance of each transponder (10-16) with respect to the interrogation unit (20), the interrogation unit (20) detects and receives the strongest response. The received identification code is stored. The interrogation unit (20) repeatedly sends interrogation pulses containing any stored identification code until all of the transponders (10-16) are identified and read.

Title
Apparatus and method for identifying multiple transponders
Application Number
8/282096
Publication Number
5602538
Application Date
July 27, 1994
Publication Date
February 11, 1997
Inventor
Andreas Hagl
Dachau
DE
Kurt Orthmann
Munich
DE
Agent
Richard L Donaldson
James C Kesterson
Rebecca A Mapstone
Assignee
Texas Instruments Incorporated
TX, US
IPC
H04B 7/00
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