Linearity improvement of high efficiency envelope tracking amplifier using dynamic gate voltage

This paper presents a linearity improvement of an envelope tracking (ET) power amplifier by controlling not only the drain voltage but also the gate voltage. These voltages are dynamically controlled according to the input envelope. It has already reported that the linearity characteristics of the microwave amplifiers change depending on the operating gate voltage. We adopted this gate voltage control to the ET power amplifier. The proposed ET power amplifier controlling both the drain and gate voltage could improve about 33 dB of IMD3 compared with the normal ET amplifier, which controls only drain voltage.