| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a non-contact IC card system capable of maintaining a success rate of transmission and reception of data, and a reader writer thereof. <P>SOLUTION: The system is equipped with a transmitting and receiving integrally formed coil 5 used for both transmission and reception, a transmitting circuit 2 connected to the transmitting and receiving integrally formed coil 5, a receiving circuit 3 connected to the transmitting and receiving integrally formed coil 5 in parallel to the transmitting circuit 2, and a load resistance 6 provided between the transmitting circuit 2 and receiving circuit 3, the resistance value of the load resistance 6 being set so that the intensity of a magnetic field which is produced with a magnetic field induced with a current 8 flowing to the transmitting and receiving integrally formed coil 5 is prevented from being affected by the impedance of the receiving circuit 3 with respect to the center frequency of a transmit signal. <P>COPYRIGHT: (C)2004,JPO |
