05053774 is referenced by 522 patents and cites 11 patents.

A transponder arrangement is described comprising an interrogation unit (10) which sends an RF interrogation pulse to at least one responder unit (12). The responder unit (12) then transmits back data stored therein in the form of a modulated RF carrier to the interrogation unit (10). In the responder unit (12) is an energy accumulator (136) which stores the energy contained in the RF interrogation pulse. The responder unit (12) further contains means (142, 148) which in dependence upon the termination of the reception of the RF interrogation pulse and the presence of a predetermined energy amount in the energy accumulator (126) initiate the excitation of an RF carrier wave generator (130, 132, 134) operating with the frequency contained in the RF interrogation pulse. Further means (158, 192) are provided which from the output signal of the RF carrier wave generator (130, 132, 134) generate a control signal which is utilized to maintain the RF carrier wave and to modulate the RF carrier to be sent back with the stored data.

Title
Transponder arrangement
Application Number
216756
Publication Number
5053774
Application Date
February 13, 1991
Publication Date
October 1, 1991
Inventor
Rudolf Kremer
Wartenberg
DE
Guenter Heinecke
Langenbach
DE
Josef H Schuermann
Oberhummel
DE
Agent
Melvin Sharp
James T Comfort
James C Kesterson
Assignee
Texas Instruments Deutschland
DE
IPC
G01S 13/80
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