CONTACTLESS IC CARD DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a contactless IC card device which can accurately transmit and receive the data. SOLUTION: An OSC 11 of a reader/writer 1 produces a 1st clock signal that is used as the timing reference for reception and transmission of data. A divider 13 transmits a 1st electromagnetic wave based on the 1st clock signal, and a modulator 14 receives the transmitting data based on the 1st clock signal and transmits a 2nd electromagnetic wave that is modulated by the transmitting data. A power extraction circuit 33 of an IC card 3 receives the 1st electromagnetic wave and extracts the power of a power supply from the received 1st electromagnetic wave. A clock extraction circuit 38 receives the 1st electromagnetic wave and extracts a 2nd clock signal synchronous with the 1st clock signal from the received 1st electromagnetic wave. A demodulator 34 receives a 2nd electromagnetic wave and extracts the transmitting data from the 2nd electromagnetic wave based on the 2nd clock signal. Then a memory 36 records the transmitting data which are extracted by the demodulator 34.