Asymmetric Doherty power amplifier at 2.2 GHz with 8.2 dB output power back-off

This work presents the design and implementation of a 10 W asymmetric Doherty power amplifier (ADPA) with 8.2 dB back-off at 2.2 GHz in Gallium Nitride (GaN) High Electron Mobility Transistors (HEMTs) technology. The amplifier was designed to achieve high efficiency over an increased dynamic range for applications with high peak-to-average power ratios (PAPRs). In order to obtain high efficiency upto 8 dB power back-off (PBO), an even input power divider and two equally sized active devices for the carrier and the peaking PAs operating in class-B and class-C, respectively, were employed. The measured peak output power of the ADPA is 39.9 dBm at the 1 dB compression point (P1dB) with 45.2 % drain efficiency (η) and 39.0 % power added efficiency (PAE). Additionally, η and PAE of 42.0 % and 38.0 % are measured at 8.2 dB PBO from P1dB.

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