A High Gain Doherty Amplifier Using Embedded Drivers

A high power and high gain Doherty amplifier is designed by using embedded driver amplifiers in the final stage. The operational characteristics of a two-stage Doherty amplifier are analyzed, as a function of the two-stage peaking amplifier gate biases. The peaking amplifier's driver has a significant effect on the total efficiency of the Doherty amplifier by reducing the leakage current. The driver stages and final output stages are implemented using two single-ended MRF21045s and a single push-pull packaged MRF5P21180. This two-stage Doherty amplifier demonstrated 27 dB gain with a PAE of 22 % at 15 W average output power, backed off 10 dB

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