Stored data inductive reading method e.g. for smart cards

摘要

A smart card has data that is to be read and transmitted by a non contact inductive transmission. The data source card D is positioned near a small transmitter coil K coupled to an ac generator W. A main field is provided by a coil R coupled to a transmitter S and this is in the form of an intermittent excitation. The data is read from the card as a data sequence and is identified by the transmitter coil or by a separate reading coil as an amplitude modulated signal.