High dynamic range, high efficiency power amplifiers for wireless communications

This paper provides an overview of power amplifier architectures for high efficiency and linearity over a wide range of output power levels, as required in CDMA, WLAN and other mobile wireless applications. Envelope tracking and Doherty amplifiers are described and issues for their implementation with HBTs are discussed. Envelope tracking implementation issues are reviewed. A Doherty CDMA amplifier with high overall efficiency (averaged over output power levels) is presented.