Amplifier circuit

• US 20070030063A1
• Filed: 10/20/2004
• Published: 02/08/2007
• Est. Priority Date: 10/20/2003
• Status: Abandoned Application

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Sasaki, Makoto, Ikeda, Kazuhiko, Izumi, Takashi
• Application Number:
  US10/575,463
• Publication Number:
  US 20070030063A1
• Time in Patent Office: Days
• US Class Current: 330/124.R
• CPC Class Codes: H03F 1/32 Modifications of amplifiers to reduce non-linear distortion by negative feedback H03F1/34
• CPC Class Codes: H03F 2200/372 Noise reduction and elimination in amplifier
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H04B 2001/0408 with power amplifiers

Abstract

A circuit capable of improving communication quality. In this circuit, constant-envelope signal generating section (101) generates a first constant-envelope signal and a second constant-envelope signal from input signals (Si, Sq). Phase-shifter (102a) shifts the phase of the first constant-envelope signal by +α° and phase-shifter (102b) shifts the phase of the second constant-envelope signal by +β°. Local signal phase-shifter (107a) shifts the phase of the local signal from local oscillator (106) by −α°, and local signal phase-shifter (107b) shifts the phase of the local signal from local oscillator (106) by −β°. Mixers (103a, 103b) performs frequency-conversion of the first constant-envelope signal and the second constant-envelope signal from phase shifters (102a, 102b) using the local signals from local signal phase-shifters (107a, 107b). Amplifiers (104a, 104b) amplify signals from mixers (103a, 103b). Combining circuit (105) combines signals from amplifiers (104a, 104b).

Claims

1. An amplifier circuit comprising:

a generating section that generates a first local signal and a second local signal which are used in frequency conversion of a first constant-envelope signal and a second constant-envelope signal having respective predetermined phases, the first local signal and the second local signal having a 180°

phase difference therebetween;

a frequency conversion section that performs frequency-conversion of the first constant-envelope signal and the second constant-envelope signal using the generated first local signal and second local signal;

an amplifying section that amplifies the frequency-converted first constant-envelope signal and second constant-envelope signal; and

a combining section that combines the amplified first constant-envelope signal and second constant-envelope signal.

2. The amplifier circuit according to claim 1, further comprising a local signal phase adjustment section that adjusts a phase of at least one of the generated first local signal and second local signal.

3. The amplifier circuit according to claim 2, further comprising:

a detecting section that detects a level of leakage of the local signals in an output signal obtained as a result of combining by the combining section; and

a phase control section that controls the local signal phase adjustment section in such a manner that the detected level is minimized.

4. The amplifier circuit according to claim 1, further comprising a local signal amplitude adjustment section that adjusts an amplitude of at least one of the generated first local signal and second local signal.

5. The amplifier circuit according to claim 4, further comprising:

a detecting section that detects a level of leakage of the local signals in an output signal obtained as a result of combining by the combining section; and

an amplitude control section that controls the local signal amplitude adjustment section in such a manner that the detected level is minimized.

6. The amplifier circuit according to claim 1, further comprising a constant-envelope signal phase adjustment section that adjusts a phase of at least one of the frequency-modulated first constant-envelope signal and second constant-envelope signal.

7. A wireless base station apparatus comprising the amplifier circuit according to claim 1.

8. A wireless terminal apparatus comprising the amplifier circuit according to claim 1.