This letter presents a wideband power amplifier (PA) with high efficiency integrated filtering characteristic. A novel bandpass filtering impedance transformer was proposed, which consists of a terminated coupled line structure (TCLS) and impedance tuning network (ITN), to realize the input matching network (IMN) and output impedance matching network (OMN). To enhance the efficiency of PA, the second harmonic has also been controlled perfectly. This design method can not only provide high-selectivity bandpass responses and high efficiency but also broaden the operation band. For demonstration, a wideband filtering PA operating at 2.2 GHz with a bandwidth of 400 MHz by employing a 10-W GaN HEMTs is fabricated. Measured results show the maximum drain efficiency (DE) is 68.3%–78.4% in the design band. Meanwhile, a good filtering performance was obtained. The rejection level was larger than 52.8 and 31 dB for the lower and higher suppression bands, respectively. In addition, simulation results show that the IMD2 and IMD3 were also improved simultaneously. In particular, the IMD2 value was improved about 30–40 dB.

中文翻译：

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具有扩展带宽和高效率的带通滤波功率放大器

这封信介绍了具有高效集成滤波特性的宽带功率放大器 (PA)。提出了一种新型带通滤波阻抗变换器，它由端接耦合线结构（TCLS）和阻抗调谐网络（ITN）组成，以实现输入匹配网络（IMN）和输出阻抗匹配网络（OMN）。为了提高PA的效率，二次谐波也得到了完美的控制。这种设计方法不仅可以提供高选择性的带通响应和高效率，还可以拓宽工作频带。为了演示，使用 10-W GaN HEMT 制造了一个工作频率为 2.2 GHz、带宽为 400 MHz 的宽带滤波 PA。测量结果显示设计范围内的最大漏极效率 (DE) 为 68.3%–78.4%。同时，获得了良好的过滤性能。对于较低和较高的抑制频带，抑制水平分别大于 52.8 和 31 dB。此外，仿真结果表明，IMD2和IMD3也同时得到改善。特别是，IMD2 值提高了约 30–40 dB。