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. 10, 2009
Filed:
Jan. 04, 2007
Naga A. Ayachitula, Elmsford, NY (US);
Stephen Brady, White Plains, NY (US);
Shu-ping Chang, Shrub Oak, NY (US);
James S. Lipscomb, Yorktown Heights, NY (US);
Frank L. Stein, Vienna, VA (US);
Naga A. Ayachitula, Elmsford, NY (US);
Stephen Brady, White Plains, NY (US);
Shu-Ping Chang, Shrub Oak, NY (US);
James S. Lipscomb, Yorktown Heights, NY (US);
Frank L. Stein, Vienna, VA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An embodiment of the invention is a method of accurately determining the spatial location of an RFID tag in two-dimensions or three-dimensions. The method utilizes a plurality of RFID readers to make a plurality of distance, direction, and or time-of-flight determinations. Such determinations are made by sending a request signal from one of the plurality of RFID readers and listening for a response signal from an RFID tag received at each of the plurality of RFID readers. Correction factors are then determined and the time-of-flight factors adjusted. The adjusted time-of-flight factors are then used to determine more accurately the distances between the RFID tag and each of the plurality of RFID readers. These more accurate distance measurements are then used to determine the spatial location of the RFID tag.