Design of a dual-band Doherty power amplifier utilizing improved combiner

This paper proposes a novel design methodology for dual-band Doherty power amplifier (DPA) with improved dual-band combiner. The presented design method simplifies and optimizes structure of dual-band DPA. According to the theoretical analysis and measurement verification, the DPA with improved combiner can provide a high efficiency at both low and high input power levels at two working frequency bands. For a continuous-wave (CW) output power of 20 W, the measured peak drain efficiency (DE) of the DPA is 62.1% and 71.4% at 2.02 and 2.63 GHz, respectively. Furthermore, the DPA achieves a DE of 51.1% with an output power of 37.9 dBm at 2.02 GHz, and a DE of 53.3% with an output power of 38.6 dBm at 2.63 GHz at 6 dB output power back-of (OBO) from the saturated output power.