Design of Doherty power amplifier for base-station application

This paper expounds on the design of Doherty power amplifier. The principle of Doherty power amplifier is analyzed detailedly. We also introduce the procedure of designing matching networks. A Doherty power amplifier at band 2.11–2.17GHz is simulated with the MRF8S21120H transistor. The P1dB is above 52dBm, and its efficiency is above 41% in 6dB back-off region. It demonstrates an efficiency improvement of 12.1% at 6dB back-off point. And the upper IMD3 is −36.4dBc, the lower IMD3 is −36dBc, at 6.5dB back-off point. It has an acceptable linearity.