The recirculating planar crossed-field amplifier (RPCFA) was designed, constructed, and tested at the University of Michigan. The RPCFA was driven by a number of RF sources ranging in frequency from 2.40 to 3.05 GHz and powers of 1 to 800 kW. Pulsed voltage was delivered to the cathode by the Michigan electron long beam accelerator with ceramic insulator (MELBA-C) which was configured to supply pulses of −300 kV, 1–10 kA, with 0.3–1.0- $\mu \text{s}$ pulse lengths. The RPCFA demonstrated zero-drive stability and a bandwidth of 15%. Amplification of microwave signals, at the design frequency of 3 GHz, below 150 kW, was observed with a mean gain of 7.87 dB and high variability, $\sigma = 2.74$ dB. Filtering this data set to only include shots with identical voltage and current profiles yielded a gain of 6.6 ± 1.6 dB. The mean gain increased to 8.71 dB and the variability decreased to $\sigma =0.63$ dB when the injected microwave power increased beyond 150 kW. Peak output powers of nearly 6 MW were achieved with RF breakdown limiting the maximum output power of the device.

中文翻译：

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循环平面交叉场放大器的大功率放大实验

循环平面交叉场放大器 (RPCFA) 是在密歇根大学设计、制造和测试的。RPCFA 由多个射频源驱动，频率范围为 2.40 至 3.05 GHz，功率为 1 至 800 kW。带有陶瓷绝缘体的密歇根电子长束加速器 (MELBA-C) 将脉冲电压传送到阴极，该加速器配置为提供 -300 kV、1-10 kA、0.3-1.0- $\mu \text{s}$ 脉冲长度。RPCFA 展示了零驱动稳定性和 15% 的带宽。微波信号的放大，在 3 GHz 的设计频率下，低于 150 kW，观察到平均增益为 7.87 dB 和高可变性， $\sigma = 2.74$ D b。将此数据集过滤为仅包含具有相同电压和电流分布的镜头，可产生 6.6 ± 1.6 dB 的增益。平均增益增加到 8.71 dB，变异性减少到 $\sigma =0.63$ 当注入的微波功率增加超过 150 kW 时的 dB。通过射频击穿限制了设备的最大输出功率，实现了接近 6 MW 的峰值输出功率。