Envelope Following-Based RF Transmitters Using Switching-Mode Power Amplifiers

This research presents a high-efficiency linear radio frequency transmitter applying the envelope-following technique to a switching-mode power amplifier. The use of predistorted envelope and quadrature-modulated signals can linearize the nonlinear behavior with fairly high average efficiency. The experimental results show that the proposed transmitter can deliver a 1.9-GHz CDMA2000 1times signal with high adjacent channel power ratio, low error vector magnitude, and high power added efficiency over a wide range of modulated output power