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:
Jun. 10, 2003
Filed:
Mar. 01, 2001
Howard William Whitesmith, Cambridge, GB;
Timothy John Palmer, Cambridgeshire, GB;
Alan Edward Ball, Cambridgeshire, GB;
Tagtec Limited, Cambridge, GB;
Abstract
A system is disclosed for monitoring the position of one or more RFID tags . The system has a detector incorporating circuitry for detecting changes in the range of an RFID tag from the detector and for triggering an alarm if a detected change in range of an RFID tag exceeds a predetermined threshold or if the RFID radio tag cannot be detected by the detector . Range may be detected, for example, by measuring the time of a returned radio signal from a tag , by measuring the strength of a returned radio signal from a tag, or by detecting changes in a periodic interval at which energy is transmitted by a tag.