Gao Xingfu, Song Lili, Zhang Haoran, Wang Lei, Ling Junpu, He Juntao
College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, People's Republic of China.
Rev Sci Instrum. 2021 Sep 1;92(9):094704. doi: 10.1063/5.0062144.
In this paper, a Ka-band coaxial transit time oscillator (TTO) with internal extraction is proposed. Particle-in-cell simulation of this oscillator is performed to obtain results as follows: under the conditions of a diode voltage of 459 kV, current of 3.9 kA, and guiding magnetic field of 0.5 T, microwaves with an output power of 0.75 GW and a frequency of 31.4 GHz can be achieved with an efficiency of 42% and a saturation time of nearly 25 ns. Moreover, the asymmetric mode competition is suppressed in the preliminary experiments. The study of a Ka-band TTO aims to extend the working frequency of high power microwave sources to a higher level. Such a device has three merits. First, it implements high power and high efficiency. Second, the internal extraction of the microwave output decreases the over-mode ratio in the microwave extraction region. Third, the over-mode ratio of the internal extraction is smaller compared with the external extraction, which can effectively suppress asymmetric mode competition.
本文提出了一种具有内部引出结构的Ka波段同轴渡越时间振荡器（TTO）。对该振荡器进行了粒子模拟，得到如下结果：在二极管电压为459 kV、电流为3.9 kA、引导磁场为0.5 T的条件下，可实现输出功率为0.75 GW、频率为31.4 GHz的微波，效率为42%，饱和时间约为25 ns。此外，在初步实验中抑制了非对称模式竞争。对Ka波段TTO的研究旨在将高功率微波源的工作频率扩展到更高水平。这种装置具有三个优点。第一，它实现了高功率和高效率。第二，微波输出的内部引出降低了微波引出区域的过模比。第三，与外部引出相比，内部引出的过模比更小，可有效抑制非对称模式竞争。
