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:
Nov. 18, 2003
Filed:
Dec. 08, 1999
John P. Bradin, Boulder, CO (US);
HID Corporation, Irvine, CA (US);
Abstract
A reader for an RFID system has an exciter circuit for generating an excitation signal and a feedback circuit coupled to the exciter circuit for automatically tuning the exciter circuit. The exciter circuit has at least one retunable component providing the exciter circuit with adjustable component values and a plurality of signal generating states. The exciter circuit is initially tuned to a first signal generating state, but is retunable to additional signal generating states by adjusting the component value of the retunable component. The feedback circuit includes a circuit evaluator coupled to the exciter circuit for determining a value of an operational parameter of the exciter circuit. A decision-making circuit is coupled to the circuit evaluator for formulating a decision in response to the value of the operational parameter. An adjustment circuit is coupled to the decision-making circuit and exciter circuit for receiving the decision and conveying an adjustment instruction to the exciter circuit in response to the decision.