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:
Apr. 08, 1997
Filed:
Jul. 11, 1995
Shuzo Fujioka, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A non-contact IC card or a non-contact IC card reader/writer has an antenna for receiving a signal transmitted from the reader/writer or the IC card, a receiver circuit for demodulating the signal received by the receiving antenna and for converting the demodulated signal into a received data signal, a control circuit for data processing in response to the received data signal, a transmitter circuit for forming a transmission signal in response to a data signal supplied by the control circuit and for setting the transmission width of the transmission signal corresponding to one data bit to a value smaller than the signal width of one data bit, and a transmitting antenna for transmitting the transmission signal from the transmitter circuit to the reader/writer or the IC card. According to a data transmission method of the invention, a data row having a first data item as dummy data is transmitted from the non-contact IC card to the reader/writer and the amplification of the received signal in the reader/writer is controlled so that the intensity of the received dummy data is equal to a predetermined value.