| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an amplifier circuit which is capable of improving communication quality and improving power efficiency, on a final stage for amplifying a transmission signal. <P>SOLUTION: A constant envelop signal production part 101 produces, from input signals Si, Sq, first and second constant envelop signals. A phase shifter 102a shifts the phase of the first constant envelop signal by a degree of +α°, and a phase shifter 102b shifts the phase of the second constant envelop signal by a degree of +β°. A local signal phase shifter 107a shifts the phase of a local signal from a local oscillator 106 by a degree of -α°, while a local signal phase shifter 107b shifts the phase of the local signal from the local oscillator 106 by a degree of -β°. Mixers 103a, 103b use the local signals from the local signal phase shifters 107a, 107b to frequency convert the first and second constant envelop signals from the phase shifters 102a, 102b. Amplifiers 104a, 104b amplify the signals from the mixers 103a, 103b. A synthetic circuit 105 combines signals from the amplifiers 104a, 104b. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
