The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 11, 1994
Filed:
Oct. 09, 1992
Josef H Schurmann, Oberhummel, DE;
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A method is described for reading the data stored in a passive responder (20) by means of an interrogation device (10) including a receiving section (14). To initiate a read cycle the interrogation device (10) transmits an HF interrogation pulse which on reception in the responder (20) is used to generate a supply voltage and initiates the transmission of an HF signal coded with the stored data. The frequency of the HF interrogation pulse is varied during its transmission over a predetermined range containing the nominal frequency of the responder (20). The receiving section (14) of the interrogation device (10) includes a tuning circuit (15) which adjusts the receiving frequency of the receiving section (14) to the frequency of the HF signal transmitted by the responder (20).