| 摘要 |
PROBLEM TO BE SOLVED: To provide a LINC (linear amplification with nonlinear components) type amplifier circuit capable of enhancing the power efficiency of an amplifier, while performing transmission power control over a wide dynamic range. SOLUTION: Fixed envelope signals S1 and S2 generated by a fixed envelope signal generating part 102 are amplified by amplifiers 104a and 104b. When the amplified fixed envelope signals S1 and S2 by transmission power that is equal to and greater than a certain threshold are output, first selection circuits 105a and 105b and second selection circuits 108a and 108b select the paths of second amplifiers 106a and 106b to transmit the amplified fixed envelope signals S1 and S2, and a synthesis circuit 109 synthesizes the signals S1 and S2 and outputs a signal S. Also, when the fixed envelope signals S1 and S2 are output by transmission power that is not greater than the certain threshold, the first selection circuits 105a and 105b and the second selection circuits 108a and 108b are controlled to select the paths of lines 107a and 107b having no amplifier, and a signal S obtained by synthesizing the signals S1 and S2 by the synthesis circuit 109 is outputted. COPYRIGHT: (C)2007,JPO&INPIT |
