摘要 |
A power amplifier includes: an amplifier; a matching circuit, including a variable reactance magnetic device having a reactance which varies in accordance with a magnetic field, configured to match an output of the amplifier with a certain impedance; an amplitude detector configured to detect the amplitude of an input signal for the amplifier; and a magnetic-field control circuit configured to apply a magnetic field corresponding to the amplitude detected by the amplitude detector to the variable reactance magnetic device. |