In this letter, at the first step, design of a new broadband planar 9:1 transmission line impedance transformer is investigated and several parameters of this transformer, such as characteristic impedances of the lines, their length, and ground plane distance effects, are analyzed from a new point of view. Then, a multioctave power amplifier (PA) is implemented using the introduced transformer as input and output matching network of a power transistor. The fabricated PA achieves a power output more than 46.5 dBm with a flat gain of 10.5 ± 0.7 dB over an ultrawide frequency band from 0.5 to 3 GHz. The measured power added efficiency (PAE) is better than 50% over the whole frequency bandwidth.

中文翻译：

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使用 9:1 平面阻抗变压器的多倍频程功率放大器设计

在这封信中，首先研究了新型宽带平面 9:1 传输线阻抗变压器的设计，并分析了该变压器的几个参数，例如线路的特性阻抗、长度和接地平面距离效应从一个新的角度。然后，使用引入的变压器作为功率晶体管的输入和输出匹配网络来实现多倍频程功率放大器 (PA)。制造的 PA 在 0.5 至 3 GHz 的超宽频带内实现了超过 46.5 dBm 的功率输出，并具有 10.5 ± 0.7 dB 的平坦增益。测得的功率附加效率 (PAE) 在整个频率带宽内优于 50%。