RADIO FREQUENCY POWER AMPLIFIER AND METHOD FOR INCREASING POWER ADDED EFFICIENCY AND LINEARITY

摘要

A radio frequency (RF) power amplifier is disclosed. The RF power amplifier includes an impedance transformation circuit, a current unit gain amplifier, and an output match circuit. The impedance transformation circuit receives a first input power signal and outputs a second input power signal correspondingly, wherein the impedance transformation circuit transforms an input impedance to an output impedance according to an impedance matching parameter for increasing power added efficiency of a pre-stage circuit. The current unit gain amplifier provides a linear transimpedance so as to transmit an input current to an output impedance, and then generate a linear output power for increasing power added efficiency of the current unit gain amplifier, wherein the impedance matching parameter is determined by a first system voltage, a second system voltage, and a predetermined power gain value.