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. 21, 2000
Filed:
Jul. 16, 1998
Shuzo Fujioka, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A recognition system for non-contact IC cards that avoids the collision of response signals with a simple construction. A non-contact IC card in this system has a first transmitter that immediately transmits a response signal at a predetermined time slot for a first polling trial by the reader/writer and a second transmitter that transmits a response signal at a randomly time slot from a predetermined number of succeeding time slots, in response to a subsequent polling trial by the reader/writer. A reader/writer in this system has a polling unit that waits for the return of a response signal from a non-contact IC card at the predetermined time slot during the execution of a first polling trial and waits for the return of a response signal from a non-contact IC card at the randomly selected time slot during the execution of the subsequent polling trials.