Patent ID: 6304613
Filing Date: 2001-10-16
Classification: G06K

Abstract:
A data carrier processing system comprising:a receiver adapted to receive and to supply a carrier signal which has been amplitude-modulated in dependence on transmitted data,one or more rectifiers, operably coupled to the carrier signal, that are adapted to generate a d.c. supply voltage corresponding to the carrier signal,a voltage limiter adapted to limit the d.c. supply voltage to a first limit value,a demodulator, operably coupled to the carrier signal, that is adapted to supply a data signal representative of the transmitted data, anda processor adapted to process the data signal supplied by the demodulator,the processor having a power supply input that is arranged to receive the d.c. supply voltage,wherein:the voltage limiter is adapted to limit the d.c. supply voltage to the first limit value with a delay to amplitude variations in the carrier signal,the voltage limiter is further adapted to limit the d.c. supply voltage to a second limit value without delay to amplitude variations in the carrier signal, andthe second limit value is higher than the first limit value.