A novel frequency-agile power amplifier (PA) designed with a modified class-J theory enforcing constant maximum and minimum instantaneous drain voltages for all frequencies is presented. The resulting high-efficiency class-J mode that requires a reconfigurable drain supply exhibits clockwise fundamental- and second-harmonic load impedance trajectories versus frequency facilitating the PA design. This clockwise-loaded class-J (CLCJ) mode enables frequency-agile capability with enhanced efficiency when the proper drain supply voltage codesigned with the clockwise fundamental and harmonic loads is applied. The CLCJ PA designed from 0.8 to 2.4 GHz exhibits the measured drain efficiency in 57%–78% and 61%–86% ranges when operated in low and high compressions, respectively. To validate the frequency agility, 3G (2.84 MHz), 4G (20 MHz), and 5G (100 MHz) modulated signals were measured at different operating frequencies from 0.8 to 2.4 GHz. At 2 GHz, the average drain efficiency improved from 53% to 68% for CW signals and from 56.6% to 66.3% for a frequency-modulated 30-MHz chirp radar signal with second-harmonic injection.

中文翻译：

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具有顺时针基波和二次谐波负载的捷变频率 J 类功率放大器

提出了一种采用改进的 J 类理论设计的新型频率捷变功率放大器 (PA)，可在所有频率下强制保持恒定的最大和最小瞬时漏极电压。由此产生的高效率 J 类模式需要可重新配置的漏极电源，呈现出顺时针基波和二次谐波负载阻抗轨迹与频率的关系，有助于 PA 设计。当应用与顺时针基波和谐波负载共同设计的适当漏极电源电压时，这种顺时针加载 J 类 (CLCJ) 模式可实现频率捷变能力并提高效率。设计为 0.8 至 2.4 GHz 的 CLCJ PA 分别在低压缩和高压缩下工作时显示出测量的漏极效率在 57%–78% 和 61%–86% 范围内。为了验证频率捷变，3G (2.84 MHz)、4G (20 MHz)、和 5G (100 MHz) 调制信号在 0.8 至 2.4 GHz 的不同工作频率下进行测量。在 2 GHz 时，连续波信号的平均漏极效率从 53% 提高到 68%，具有二次谐波注入的调频 30-MHz 线性调频雷达信号从 56.6% 提高到 66.3%。