This letter presents a power-amplifier (PA)-stabilization technique based on the low-frequency out-of-band feedback. The proposed structure replaces a conventional stability network to ensure unconditional stability at the frequencies up to the radio-frequency (RF) operating band, with the in- and above-band frequencies stabilized through the matching network design. The approach offers an alternative to inserting the lossy components in the RF signal path, which can significantly degrade the realizable in-band gain of the amplifier. The 900-MHz proof-of-concept PA based on a 10-W gallium-nitride (GaN) device is characterized under the continuous-wave (CW) and Wideband Code Division Multiple Access signal (W-CDMA) excitations and realizes 25.6-dB small-signal gain and 73% power added efficiency (PAE) at P3dB.

中文翻译：

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通过带外反馈稳定功率放大器

这封信提出了一种基于低频带外反馈的功率放大器 (PA) 稳定技术。所提出的结构取代了传统的稳定性网络，以确保在高达射频 (RF) 工作频段的频率上无条件稳定性，并通过匹配网络设计稳定带内和带上频率。该方法提供了在 RF 信号路径中插入有损组件的替代方法，这会显着降低放大器的可实现带内增益。基于 10-W 氮化镓 (GaN) 器件的 900-MHz 概念验证 PA 在连续波 (CW) 和宽带码分多址信号 (W-CDMA) 激励下具有特征，并实现了 25.6- dB 小信号增益和 73% 的 P3dB 功率附加效率 (PAE)。