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:
Mar. 12, 2002
Filed:
Sep. 02, 1999
Anil Gercekci, Bellevue, CH;
Paul De Champs, Ferney Voltaire, FR;
Atmel Research, Georgetown, GC;
Abstract
A method of communicating with a plurality of contactless data carriers and a contactless data carrier for use in communicating with a base station. The method of communicating includes the base station transmitting a wake up signal for a plurality of contactless data carriers which are in a wait state. Then, the data carriers exit the wait state and transmit identity information to the base station in a time slot that is randomly self-assigned. The base station registers the identity information by polling the registered data carriers and initiates dialogue with registered data carriers in an order determined by the randomly self-assigned time slots of the registered data carriers. The method of communication helps to avoid the problem of data collision that often occurs when multiple contactless data carriers or smart cards operate in the field of a single base station or card reader.