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:
Apr. 13, 2004
Filed:
Jan. 15, 2002
Daniel L. Johnson, Columbia Heights, MN (US);
Yuri Smirnov, Eagan, MN (US);
Digital Angel Corporation, South St. Paul, MN (US);
Abstract
An omni-directional RFID antenna is provided for use with a remote interrogator/reader system used for identifying tagged animals. A pair of antenna coils are arranged in a crossing pattern that results in the creation of an omni or multi-directional electromagnetic field. Additionally, the crossing pattern creates out of phase null zones at quadrants within the crossing pattern of the antennae that reduces interference caused by RF noise generated from the environment. The omni-directional electromagnetic field effectively surrounds each of the null zones thereby allowing an RFID transponder to be successfully interrogated despite the orientation of the transponder as it passes through the electromagnetic field.