| 摘要 |
PROBLEM TO BE SOLVED: To provide a communication equipment for non-contact IC card that successively changes the frequency of communications between a reader/writer and a non-contact IC card(NCC), and is hardly affected by disturbance. SOLUTION: In the beginning of processing, the inquiry signal for communication state is generated from the reader/writer to the NCC in the S1 and when a response is confirmed in the S2, communication processing is performed in the S3 but when there is no response, a disturbance check is performed in the S4. Continuously, the presence/absence of disturbance is investigated in the S5 and when there is no disturbance, processing is returned to the S1 but when there is the disturbance, the frequency of disturbance is discriminated in the S6. Finally, a clock frequency for communication is changed in the S7. |
