A class E amplifier with power supply modulation and a predistorted input signal

摘要

The amplitude of the input signal Vin for a class E power amplifier 20 with power supply modulation 18 is adjusted by a predistorter 22 in order to achieve either optimum linearity or power added efficiency. Optimum efficiency is achieved by avoiding underdriving or overdriving of the amplifier 20. Optimum linearity is achieved by adjusting the amplitude of Vin to achieve a linear relation between the output signal magnitude and the supply voltage Vds. The predistorter 22 may alternatively or additionally adjust the phase of Vin to correct the amplifier's phase response. The predistorter 22 may use a lookup table or polynomial equation. An amplitude limiter 16 may be arranged before the predistorter.