High-frequency power amplifier

A high-frequency power amplifier comprising:

• a transistor which is inputted with a high-frequency signal, amplifies the high-frequency signal and outputs the same;
• a fundamental-signal matching circuit one end of which is connected to an output of said transistor and which matches at least the impedance of fundamental signal in the amplified high-frequency signal and outputs the same from the other end;
• a power supply which supplies electric power to said transistor from a node located in an interval from the output of said transistor to said fundamental-signal matching circuit;
• a first inductor, one end of which is connected to said power supply;
• a second inductor connected in series between the other end of said first inductor and said node;
• a third inductor, one end of which is connected to said node;
• and
• a first capacitor, one end of which is connected to the other end of said third inductor while the other end thereof is connected to said reference potential, said first capacitor forming a first series-resonant circuit with said third inductor and a parallel-resonant circuit with said first inductor.

A high-frequency power amplifier comprising:

• a transistor which is inputted with a high-frequency signal, amplifies the high-frequency signal and outputs the same;
• a fundamental-signal matching circuit, one end of which is connected to an output of said transistor and which matches at least the impedance of fundamental signal in the amplified high-frequency signal and outputs the same from the other end;
• a power supply which supplies electric power to said transistor from a node located in an interval from the output of said transistor to said fundamental matching circuit;
• a first inductor, one end of which is connected to said power supply;
• a second inductor connected is series between the other end of said first inductor and said node;
• a third inductor, one end of which is connected to the output of said transistor;
• and
• a first capacitor, one end of which is connected to the other end of said third inductor while the other end thereof is connected to said reference potential, said first capacitor forming a first series-resonant circuit with said third inductor and a parallel-resonant circuit with said first inductor.