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. 20, 2004
Filed:
Feb. 14, 2000
Fujitsu Limited, Kawasaki, JP;
Abstract
A proximity IC card (PICC) which relates to and provides a carrier synchronization type demodulator, which is able to stably receive a PSK signal from a PICC and is enhanced in noise immunity, and which is realized at a low cost and in such a way as to have a small size. The carrier synchronization type demodulator is adapted to receive and demodulate PSK-modulated subcarrier signals to be synchronized with and superposed onto a sent carrier signal. This demodulator includes a carrier detecting device for detecting the subcarrier signals successively received in a predetermined time, a phase-change-point detecting device for detecting a phase change point of the subcarrier signal after the subcarrier signal is detected, and a data reception control device for controlling the reception of data of a predetermined format by employing a moment, at which the phase change point is detected, as a synchronization start point for receiving data, and by using an internal clock that is synchronized with the sent carrier signal by using the moment as a starting point of synchronization.