High-Efficiency Doherty Power Amplifiers: Historical Aspect and Modern Trends

This article presents a thorough description of Doherty power amplifier design and operation. The following are also highlighted: overview of the modern trends using Doherty techniques for multistage and asymmetric multiway structure; the basic operation principle of a conventional Doherty power amplifier is analysed and described; asymmetric N-way Doherty amplifier; and the design on implementing the transmission-line two-stage Doherty amplifier into a monolithic microwave integrated circuit (MMIC) using a pHEMT or CMOS process.