A reconfigurable series/parallel quasi-balanced Doherty power amplifier (QB-DPA) is presented with a unique capability of maintaining high linearity and high efficiency against load mismatch, which is highly desirable for massive multiple-input–multiple-output (MIMO) and active array applications. Based on the new QB-DPA topology derived from an ideal balanced amplifier, it is, for the first time, discovered that QB-DPA can be reconfigured between series- and parallel-DPA modes by setting the isolation-port loading to the ground and open circuit, respectively, and exchanging the roles of main and auxiliary amplifiers. Expanding from the ideal Doherty modes, the isolation port can be loaded with small reactance (susceptance) for linearity enhancement of series (parallel) QB-DPA. Furthermore, by leveraging the symmetry of series and parallel modes with complementary sensitivities to load impedance/admittance, it is theoretically proved that the QB-DPA can be strongly mismatch-resilient. Based upon the comprehensive and conclusive theoretical analysis, a physical prototype demonstration is practically presented using the GaN technology at 3.5 GHz. In modulated measurement using Long-Term Evolution (LTE) signals, the developed QB-DPA exhibits excellent linearity, e.g., <1.6% error vector magnitude (EVM) and high average efficiency of 45% at the rated averaged power in the nominal 50- $\Omega $ condition, which compares favorably with state of the art. More importantly, through only a two-state adaption (using silicon-on-insulator (SOI)-based switches) of reactive loading at the output isolation port together with optimized gate biasing, the high linearity (<4% EVM) and average efficiency (>31%) can be experimentally maintained up to 2.5:1 of voltage standing wave ratio.

中文翻译：

---

通过大规模/ MIMO串联/并联重配置，具有失配弹性的线性增强型准平衡Doherty功率放大器

提出了一种可重构的串联/并联准平衡Doherty功率放大器（QB-DPA），具有保持高线性度和高效率以防止负载失配的独特功能，这对于大规模多输入多输出（MIMO）和活动阵列应用程序。基于理想平衡放大器衍生的新QB-DPA拓扑，这是第一次发现可以通过将隔离端口负载设置为接地和串联来在串联DPA模式和并联DPA模式之间重新配置QB-DPA。分别开路，并交换主放大器和辅助放大器的作用。从理想的Doherty模式扩展后，隔离端口可以加载较小的电抗（电抗），以增强串联（并联）QB-DPA的线性度。此外，通过利用串联和并联模式的对称性以及对负载阻抗/导纳的互补灵敏度，可以从理论上证明QB-DPA具有很强的失配弹性。根据全面而结论性的理论分析，实际上使用3.5 GHz的GaN技术进行了物理原型演示。在使用长期演进（LTE）信号的调制测量中，开发的QB-DPA具有出色的线性度，例如<1.6％误差矢量幅度（EVM）和在标称50-dB额定平均功率下的平均效率为45％实际上使用GaN技术在3.5 GHz上进行了物理原型演示。在使用长期演进（LTE）信号的调制测量中，开发的QB-DPA具有出色的线性度，例如<1.6％误差矢量幅度（EVM）和在标称50-dB额定平均功率下的平均效率为45％实际上使用GaN技术在3.5 GHz上进行了物理原型演示。在使用长期演进（LTE）信号的调制测量中，开发的QB-DPA具有出色的线性度，例如<1.6％误差矢量幅度（EVM）和在标称50-dB额定平均功率下的平均效率为45％ $ \ Omega $ 条件，与现有技术相比是有利的。更重要的是，仅通过对输出隔离端口的无功负载进行两态适配（使用基于绝缘体上硅的开关），并优化了栅极偏置，即可实现高线性度（<4％EVM）和平均效率（> 31％）可以通过实验将电压驻波比维持在2.5：1。