| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high frequency power amplifier circuit and wireless communication system capable of controlling output power with power supply voltage, obtaining sufficient output power in a region where a requested output level is high and improving power efficiency in a region where request output power is low. <P>SOLUTION: In this high frequency power amplifier circuit or a high frequency power amplifier circuit (RF power module) configured so as to control output power by cascading two or more FETs for amplification, applying bias voltage of a prescribed level to a gate terminal to control the power supply voltage of the FETs for amplification, the FET for amplification on the last stage and the FET for amplification of a stage before the FET of the last stage are respectively provided with transistors for power supply voltage control. These transistors for power supply voltage control generate and apply power supply voltage so as to make the FET for amplification of the previous stage saturated in a stage where a request output level is comparatively low. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
