| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power amplifier which facilitates a method of controlling a gain of a forward side RF unit circuit of a Cartesian type negative feedback amplifier and employs the Cartesian type negative feedback amplifier for making the gain of the forward side RF unit circuit be predetermined gain at all the time. <P>SOLUTION: A first detector 23 is provided in an output of a power amplifier 12, a second detector 28 is provided in an output of a modulator 21, a first variable attenuator 26 is provided between the modulator 21 and the power amplifier 12, and a second variable attenuator 27 is provided between a feedback path for extracting, as a feedback modulation signal, a part of an output signal of the power amplifier 12, and a demodulator 22. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
