| 摘要 |
PURPOSE:To prevent radio interference between different systems, to reduce manufacturing cost and control cost, to surely perform a discrimination of an IC card and to improve security by making the decoding or operation analysis of the discrimination code alloted to the IC card difficult. CONSTITUTION:A master side discrimination code is always transmitted from a reader 1. In an IC card 2, a slave side discrimination code is written in a EEPROM 2-6. When the IC card 2 enters in an electromagnetic field formed by the reader 1, the master side discrimination code is received and it is given to a control logic 2-5. The control logic 2-5 reads the slave side discrimination coded, collates it with the master side discrimination code and returns a response signal when both of them coincide. The reader 1 receives the response signal from the IC card 2, confirms the existence of the normal IC card 2 and unlocks a door. |
