InnovationQ and the IP.com Prior Art Database will be updated on Sunday, December 15, from 11am-2pm ET. You may experience brief service interruptions during that time.
Browse Prior Art Database


IP.com Disclosure Number: IPCOM000009519D
Original Publication Date: 1999-Sep-01
Included in the Prior Art Database: 2002-Aug-29

Publishing Venue


Related People

Michel Burri Hans Staufer Tony Newton


The problem relates generally to detecting data in an electronic reader interface, received from a contact less smart card or tag transponder, in which the reader supplies power to the contact less card or transponder via a radio frequency transmit loop antenna. The same transmit antenna is also used to receive a back-scattered signal from the smart card or tag device which is performed with an admittance load switching device inside the card/tag circuit. The problem arises in that the received data signal developed at the transmitter coil is very small in comparison with the radio frequency transmit signal requiring high carrier rejection filtering prior to signal detection. The solution proposed is a peak track demodulator capable of detecting low-level signals in a large signal environment such as card/tag reader.