| 摘要 |
PROBLEM TO BE SOLVED: To make surely performable collective read/write operation with an IC card reader/writer even in the state of overlapping plural IC cards each other. SOLUTION: Random numbers are generated by a random number generating part 24, and on the basis of that random number, a switching control part 22 performs control to change over a switch part 20 at random. The generated random numbers or switched result determined by using that random numbers are stored in a memory 26 and can be suitably read out or can be used for switching control as well. Thus, by changing over the switch part 20 at random by the switching control part 22, the positions of antennas 14 and 16 of plural mutually overlapped IC cards 10 can be made different from each other and mutual inductance can be reduced. Therefore, when a magnetic field is generated from an IC card reader/writer 28, a current efficiently flows to the antenna 14 of each of IC cards and collective read or write can be surely performed to the plural IC cards. |
