Title :
ASK 10% demodulator for contactless smart card IC
Author :
Nebel, Gerhard ; Blum, Andreas ; Eichner, Dierk ; Güngerich, Volker ; Melchior, Marc ; Reiner, Robert ; Schraud, Gerhard ; Weder, Uwe
Author_Institution :
Infineon Technologies, München, Germany
Abstract :
A demodulator circuit for ASK 10% modulated and NRZ coded signals used in contactless chip-cards is presented. The main problem is that very small signal variations have to be detected, while the dynamic range of the signal is very large due to movement of the chip-card inside the field of the card operating device. The dynamic range of the signal has to be adapted and the demodulator must be able to distinguish between movement of the card and real modulation.
Keywords :
Amplitude shift keying; Circuits; Demodulation; Dynamic range; Frequency; Logic; Modulation coding; Optical signal processing; Smart cards; Voltage;
Conference_Titel :
Solid-State Circuits Conference, 1999. ESSCIRC '99. Proceedings of the 25th European
Conference_Location :
Duisburg, Germany
