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. 06, 2010
Filed:
Nov. 20, 2003
Giorgio Grego, Turin, IT;
Giorgio Grego, Turin, IT;
Telecom Italia S.p.A., Milan, IT;
Abstract
A method and an apparatus for reading passive tags affixed to objects to be identified and tracked by a radio frequency identification system are disclosed. An interrogating station sends radio-frequency inquiry signals toward the passive tags through an antenna array and receives the response signals from the tags through the same array. Electronic circuitry for processing such response signals has a phase conjugator submitting each received signal to phase conjugation, and the phase-conjugated signals are back transmitted to the passive tags. Retrodirectivity of the antenna array obtained through the phase conjugation allows a precise object identification and tracking also at relatively long distances.