High-frequency amplifier, feed-forward amplifier and distortion compensating amplifier

A high-frequency amplifier, comprising:

• first distributing means for distributing a high-frequency signal input from an input terminal;
• main amplifying means for always performing an amplifying operation for one high-frequency signal distributed by the first distributing means;
• subsidiary amplifying means for performing an amplifying operation for the other high-frequency signal distributed by the first distributing means only in a case where an instantaneous electric power of the high-frequency signal is high;
• and
• a circulator for injecting the high-frequency signal amplified by the subsidiary amplifying means into an output side of the main amplifying means and outputting the high-frequency signal amplified by the main amplifying means through an output terminal.

A high-frequency amplifier, comprising:

• first distributing means for distributing a high-frequency signal input from an input terminal to two lines;
• second distributing means for producing two high-frequency signals having a phase difference of 90 degrees from each other from the high-frequency signal of one line distributed by the first distributing means and distributing the two high-frequency signals;
• first main amplifying means for always performing an amplifying operation for one high-frequency signal distributed by the second distributing means;
• second main amplifying means for always performing an amplifying operation for the other high-frequency signal distributed by the second distributing means;
• subsidiary amplifying means for amplifying the high-frequency signal of the other line distributed by the first distributing means only in a case where an instantaneous electric power of the high-frequency signal is high;
• and
• a first 90-degree hybrid for injecting the high-frequency signal amplified by the subsidiary amplifying means into both an output side of the first main amplifying means and an output side of the second main amplifying means, combining the high-frequency signal amplified by the first main amplifying means and the high-frequency signal amplified by the second main amplifying means and outputting a combined high-frequency signal through an output terminal.