Performance estimation of fully digital polar modulation driving a 2 GHz switch-mode power amplifier

This paper presents a fully digital transmitter architecture based on a digital polar modulator (DPM) and switch-mode power amplifier (SMPA). A simple method for comparison and estimation of different digital modulation techniques for SMPA is described. An estimation of the proposed digital polar modulator properties was done by means of a 2.1..2.2 GHz class-F power amplifier. For a CDMA signal with 9.5 dB peak-to-average power ratio (PAPR), the class-F based amplifier module driven by DPM pulse train shows more than 1 W output power and more than 10 % of drain efficiency.