High-frequency power amplifier

• US 6,724,263 B2
• Filed: 10/28/2002
• Issued: 04/20/2004
• Est. Priority Date: 08/30/2002
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Sugiura, Masayuki
• Primary Examiner(s): Choe, Henry
• Application Number:
  US10/281,206
• Publication Number:
  US 20040041634A1
• Time in Patent Office: 540 Days
• Field of Search: 330/302, 330/303, 330/306, 333/32
• US Class Current: 330/302
• CPC Class Codes: H03F 1/565 using inductive elements
• CPC Class Codes: H03F 3/191 Tuned amplifiers H03F3/193, H03F3/195 take precedence

Abstract

A high-frequency power amplifier includes 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; and a first capacitor, one end of which is connected between said first inductor and said second inductor while the other end thereof is connected to a reference potential, said first capacitor forming a first series-resonant circuit with said second inductor and a parallel-resonant circuit with said first inductor.

Claims

1. 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; and

a first capacitor, one end of which is connected between said first inductor and said second inductor while the other end thereof is connected to a reference potential, said first capacitor forming a first series-resonant circuit with said second inductor and a parallel-resonant circuit with said first inductor.

2. The high-frequency power amplifier according to claim 1,

wherein said first series-resonant circuit and said fundamental-signal matching circuit are connected in parallel between said node and said reference voltage.

3. The high-frequency power amplifier according to claim 1,

wherein the ratio in inductance between said first inductor and said second inductor is about (n²−

1);

1 (n is an integer) and the sum of the lengths of transmission lines for forming said first inductor and said second inductor is ⅛

the wavelength of the fundamental signal or less.

4. The high-frequency power amplifier according to claim 2,

wherein the ratio in inductance between said first inductor and said second inductor is about (n²−

1);

1 (n is an integer) and the sum of the lengths of transmission lines for forming said first inductor and said second inductor is ⅛

the wavelength of the fundamental signal or less.

5. The high-frequency power amplifier according to claim 1,

wherein said first inductor and said second inductor form an integrated transmission line,

wherein the ratio in inductance between said first inductor and said second inductor is determined by the ratio of the length of the transmission line between said first inductor and said second inductor.

6. The high-frequency power amplifier according to claim 2,

wherein said first inductor and said second inductor form an integrated transmission line,

wherein the ratio in inductance between said first inductor and said second inductor is determined by the ratio of the length of the transmission line between said first inductor and said second inductor.

7. The high-frequency power amplifier according to claim 3,

wherein said first inductor and said second inductor form an integrated transmission line,

wherein the ratio in inductance between said first inductor and said second inductor is determined by the ratio of the length of the transmission line between said first inductor and said second inductor.

8. The high-frequency power amplifier according to claim 1 further comprising:

a third inductor which is connected in series between said second inductor and said node, said third inductor forming said first series-resonant circuit with said second inductor and said first capacitor; and

a second capacitor, one end of which is connected between said second inductor and said third inductor while the other end thereof is connected to the reference potential, said second capacitor forming a second series-resonant circuit with said third inductor and forming a parallel-resonant circuit with said first capacitor and said first inductor.

9. The high-frequency power amplifier according to claim 8, wherein

said first inductor, said second inductor and said third inductor form an integrated transmission line and

the ratio in inductance among said first inductor, said second inductor and said third inductor is determined by the ratio in the length of the transmission line among said first inductor, said second inductor and said third inductor.

18. The high-frequency power amplifier according to claim 5,

wherein said transmission line is a strip line or a micro strip line.

19. The high-frequency power amplifier according to claim 9, wherein

said transmission line is a strip line or a micro strip line.

10. 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.

12. The high-frequency power amplifier according to claim 10, wherein the sum of the lengths of said first inductor and said second inductor is ⅛

the wavelength of the fundamental signal or less.

14. The high-frequency power amplifier according to claim 10, further comprising a second capacitor, one end of which is connected between said first inductor and said second inductor while the other end thereof is connected to said reference potential, said second capacitor forming a second series-resonant circuit with said second inductor and a parallel-resonant circuit with said first capacitor and said first inductor.

16. The high-frequency power amplifier according to claim 10, wherein said first inductor, said second inductor and said third inductor form an integrated transmission line and

the ratio in inductance among said first inductor, said second inductor and said third inductor is determined by the ratio in the length of the transmission line among said first inductor, said second inductor and said third inductor.

20. The high-frequency power amplifier according to claim 16, wherein said transmission line is a strip line or a micro strip line.

11. 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.

13. The high-frequency power amplifier according to claim 11, wherein the sum of the lengths of said first inductor and said second inductor is ⅛

the wavelength of the fundamental signal or less.

15. The high-frequency power amplifier according to claim 11, further comprising a second capacitor one end of which is connected between said first inductor and said second inductor while the other end thereof is connected to said reference potential, said second capacitor forming a second series-resonant circuit with said second inductor and a parallel-resonant circuit with said first capacitor and said first inductor.

17. The high-frequency power amplifier according to claim 11, wherein said first inductor, said second inductor and said third inductor form an integrated transmission line and

the ratio in inductance among said first inductor, said second inductor and said third inductor is determined by the ratio in the length of the transmission line among said first inductor, said second inductor and said third inductor.

21. The high-frequency power amplifier according to claim 17, wherein said transmission line is a strip line or a micro strip line.