A CMOS dual-switching power-supply modulator with 8% efficiency improvement for 20MHz LTE Envelope Tracking RF power amplifiers

Abstract

Envelope Tracking (ET) is an efficiency enhancement technique where the power supply of a linear RF power amplifier (PA) follows the envelope of the RF signal. It is specifically effective for the high peak-to-average power ratio (PAPR) signals of modern communication systems. But due to envelope bandwidth expansion and watt-level power requirements, the design of wide bandwidth and high efficiency power supply modulators remains one of the most challenging aspects of ET systems.