CONTACTLESS IC CARD READER/WRITER

摘要

PROBLEM TO BE SOLVED: To provide a contactless IC card reader/writer capable of extending a communication range.

SOLUTION: The contactless IC card reader/writer is provided with: a receiving means for receiving a transmitted signal of an IC card represented by an intermittence of a subcarrier; a limiter means 14 for limiting a level of the received signal; narrow band tuning amplifying means 22 and 23 for filtering and amplifying the received signal in a narrow band with a subcarrier frequency as a central frequency; a low-pass filter 25 for removing the subcarrier from output signals of the narrow band tuning amplifying means 22 and 23; and a waveform shaping means 26 for comparing the signal processed by the low-pass filter 25 with a threshold to produce a signal representing presence/non-presence of the subcarrier. Only the presence of the subcarrier is detected without performing faithful reproduction of the subcarrier so that the signal from the IC card is reproduced.

COPYRIGHT: (C)2004,JPO