Experimental demonstration of an emission-gated traveling-wave tube amplifier
Experimental demonstration of an emission-gated traveling-wave tube amplifier
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DOI：
10.1109/tps.2002.801527
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发表时间：
2002-06-01
影响因子：
1.5
通讯作者：
Spindt, CA
中科院分区：
文献类型：
--
作者：
Whaley, DR;Gannon, BM;Spindt, CA
报道了采用高频发射门控场发射极阵列(FEA)冷阴极设计和运行的行波管(TWT)放大器的研制结果。行波管被保守地设计为仅在1%的阴极电流调制下工作，但结果表明，在C波段范围内实现了30%的电流调制。发射门控行波管样机的工作电流为5 mA，射频输出功率为280 mW，使用直径为300微米的FEA阴极，发射极尖端为10000个，测试采用100微秒脉冲的单脉冲模式。在所测试的所有实验条件下，显示了良好的光束控制。模拟结果表明，在相同的行波管电路和显示的阴极调制水平下，直径为1 mm的阴极在相同的频带内可以产生接近60W的输出功率，接近于80W的输出功率。如果电路针对测量的调制电平进行了优化。测量还表明，该器件的性能不会随着行波管的最大工作频率--至少7.0 GHz的频率而降低。仅有限元分析电子枪的冷测量就表明，阴极工作到20 GHz是可能的。这些结果代表了行波管中发射门阴极的第一次工作，以及在使用发射门电子源的微波真空器件中所记录的最高功率工作。
This paper reports the results of the development of a traveling-wave tube (TWT) amplifier designed and operated using a high-frequency emission-gated field emitter array (FEA) cold cathode. The TWT was conservatively designed to operate with only 1% cathode current modulation but results show that 30% modulation of the current was achieved in the C-Band frequency range. The emission-gated TWT prototype was operated up to a current of 5 mA and RF output power of 280 mW using a 300-mum diameter FEA cathode having 10 000 emitter tips with testing performed in single-pulse mode using 100-mus pulses. Excellent beam control was demonstrated under all experimental conditions tested. Simulation shows that, with the same TWT circuit and demonstrated cathode modulation level, a 1-mm diameter cathode would generate similar to60 W of output power in the, same frequency band and similar to80. W if the circuit were optimized for the measured level of modulation. Measurements also show that performance of the device does not degrade with frequency up to at least 7.0 GHz, which is the maximum operating frequency of the TWT. Cold measurements of the FEA electron gun alone indicate operation of the cathode up through 20 GHz might be possible. These results represent the first operation of an emission-gated cathode in a TWT and the highest power operation ever recorded in a microwave vacuum device using an emission-gated electron source.