| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an antenna tuner capable of transmission and reception in which matching is made between an antenna and a transmission/reception unit, even in cross-band communication having a large difference between a transmission frequency and a reception frequency. <P>SOLUTION: An antenna tuner 1 is disposed between a transmission/reception unit 2 and an antenna 3, and detects a travelling wave and a reflection wave, so as to perform matching to minimize a standing wave ratio. The antenna tuner 1 includes a matching circuit 12, and connects between the transmission/reception unit 2 and the antenna 3 through the matching circuit 12. At switching over from a reception state to a transmission state, the antenna tuner 1 sets the circuit constant of the matching circuit 12 according to the transmission frequency. At switching over from a transmission state to a reception state, the antenna tuner 1 sets the circuit constant of the matching circuit 12 according to the reception frequency. <P>COPYRIGHT: (C)2012,JPO&INPIT |
