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:
Jul. 23, 2013
Filed:
Oct. 16, 2009
Russell Hofer, St. Louis, MO (US);
Graham P. A. Bloy, St. Louis, MO (US);
Russell Hofer, St. Louis, MO (US);
Graham P. A. Bloy, St. Louis, MO (US);
RF Controls, LLC, St. Louis, MO (US);
Abstract
A method and apparatus for phase ranging the distance an RFID tag is from an RFID location system antenna along the interrogation signal beam, based upon the phase readings included in data sets obtained from monitoring reply signals corresponding to interrogation signals at multiple frequencies and a common interrogation signal beam direction; by comparison of measured phase and frequency data sets with theoretical phases calculated with respect to the same frequencies over a range of positions corresponding to a beam extent of the interrogation signal.