This letter presents the design and experimental characterization of a GaN–Si monolithic Doherty power amplifier (PA) for the KaKa -band satellite downlink. The fabricated amplifier favorably compares with the current state of the art, achieving from 16.3 to 20.3 GHz (4 GHz, 22% relative bandwidth), a record band to date, 36.6–37.7-dBm output power, 23%–31% power-added efficiency, 18–22-dB gain at saturation, and around 20% power-added efficiency at 6-dB output back-off. At 18.8 GHz, the amplifier shows a noise-to-power ratio higher than 17 dB at all power levels, making it suitable for satellite applications where additional linearization is usually unfeasible.

中文翻译：

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用于 Ka 波段卫星下行链路的 5W GaN Doherty 放大器，具有 4GHz 带宽和 17dB NPR


这封信介绍了用于 KaKa 频段卫星下行链路的 GaN-Si 单片 Doherty 功率放大器 (PA) 的设计和实验特性。所制造的放大器与当前最先进的技术相比，实现了 16.3 至 20.3 GHz（4 GHz，22% 相对带宽），这是迄今为止的记录频带，36.6–37.7-dBm 输出功率，23%–31% 功率-增加了效率，饱和时增益为 18–22dB，6dB 输出回退时功率增加效率约为 20%。在 18.8 GHz 时，该放大器在所有功率水平下的噪声功率比均高于 17 dB，因此适合通常无法进行额外线性化的卫星应用。