| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a loop coil antenna and a reader/writer which are capable of eliminating an area where communication is not possible and stably maintaining a communication distance by realizing the stabilization of an antenna matching circuit by constructing the antenna matching circuit that is not influenced even when a conductor such as a metal or a tag comes close to the reader/writer. <P>SOLUTION: In a RFID system, when the tag responds to a magnetic field area generated by an antenna coil of the reader/writer, an electric wave for transmitting information to the above reader/writer is output by activating a control circuit of the tag with a power generated at an antenna coil of the corresponding tag. As the RFID system has the antenna matching circuit which is configured by using a capacitor for a balanced unbalance conversion that is inserted between the antenna coil of the above reader/writer and a ground, a bad communication with the tag that comes close to the reader/writer is reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
