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:
Aug. 26, 2008
Filed:
Feb. 20, 2004
Edward D. Goff, Mahtomedi, MN (US);
Seth A. Lieffort, Eagan, MN (US);
Leroy Stolberg, Eagan, MN (US);
Edward D. Goff, Mahtomedi, MN (US);
Seth A. Lieffort, Eagan, MN (US);
Leroy Stolberg, Eagan, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A multi-loop antenna is described having a plurality of conductive loops to produce an electromagnetic field for radio frequency identification (RFID) communication with RFID tags. The conductive loops are spaced apart at least a distance that is selected based on a dimension of the RFID tags with which the antenna communicates. In this manner, the loops are positioned and spaced in a manner that reduces the size of the holes within the resulting magnetic field. In addition, the configuration of the described dual-loop antenna increases the coverage of the antenna, and decreases inter-winding capacitance, thereby increasing overall read range achieved by the antenna.