An envelope tracking system using a GaAs Class-AB power amplifier and a Class-AD modulator

In this paper an envelope tracking system with a maximum output power of 38 dBm operating at 2.06 GHz is presented. Static and dynamic measurements are performed. For a UMTS test signal with a peak-to-average power ratio of 11.2 dB power-added efficiency can be enhanced by 4 % to a value of 16.4 %.