KEYNOTE: Efficiency Enhancements Using Digital Predistortion and Advanced Transmitters

This talk starts with a high-level view of digital predistortion (DPD) for Class AB power amplifiers. Then presents a methodology to quantify the PA power savings, using a smaller active device or a lower supply voltage. This is used to quantify how much power can be saved, defining the power budget for DPD. Additionally, when we modulate the supply voltage, we can reduce the impact of the waveform PAPR on transmitter efficiency. Although, running into compression causes distortion, this can be compensated with the proper input control signals and waveforms. Finally, an example is presented of a commercial small cell basestation, that uses Direct-Polar supply modulation design techniques. This talk highlights how Advanced Power Amplifier systems change design assumptions, improving transmitter efficiency and maintain output signal fidelity needed in modern communication systems.