| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an authentication system having higher security by using, for authentication, information about a direction wherein a non-contact IC card is held to a communication device (a reader/writer). <P>SOLUTION: This non-contact IC card 10 exchanging information with the communication device 21 by transmission/reception of an electric wave has: a plurality of direction detection antennas 15, 16 disposed at a prescribed interval; direction detection means 11, 17, 18 detecting the direction wherein the non-contact IC card is held up to the communication device, on the basis of a difference of reception timing in the plurality of direction detection antennas of the transmission electric wave from the communication device; a direction information generation means 11 generating direction information showing the direction detected by the direction detection means; and information transmission means 12, 14 transmitting the direction information to the communication device. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
