| 摘要 |
<p>PROBLEM TO BE SOLVED: To increase the communication distance between a reader writer and a non-contact information record medium by amplifying the power of a transmit wave by a repeating device installed in the communication area of the reader/writer. SOLUTION: When a multi-frequency source reader writer 301 radiates a power transmit wave of frequency f2, a non-contact information recording repeater 501 responds to it, converts the power transmit wave of frequency f2 into a signal of frequency f1 and radiates its power-amplified transmit wave of f1. A card 101 receives it and obtains the electric power to operate, and then a data modulated wave is sent back to the multi-frequency source reader writer 301. In this case, the card 101 does not react with the repeated transmit wave of frequency f2 but reacts only to the transmitted wave of frequency f1, so that a secure with respect to the multifrequency source reader writer 301 is made.</p> |
