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:
Aug. 26, 1997
Filed:
Mar. 17, 1995
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
To receive a response signal from a radio card, a card reader transmits a carrier (not modulated) to the radio card. In the radio card, a phase modulator phase-modulates the a sub-carrier with a response signal, thereby generating a PSK signal, and a phase modulator phase-modulates the carrier with the PSK signal, producing a PSK-PSK signal. The PSK-PSK signal is supplied to an antenna via a signal-extracting device. The antenna sends the PSK-PSK signal toward the card reader. In the card reader, a distributor distributes the PSK-PSK signal to a synchronous detector and an orthogonal detector. The detectors performs synchronous detection by using carriers which differ in phase by 90.degree.. Low-pass filters extract sub-carrier components from the outputs of the detectors. The sub-carrier components are delayed and detected by delay detectors and added together by an adder. The level of the output of the adder is determined by a data discriminator, whereby the card reader obtains the response signal transmitted from the radio card.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile