Studies on Frequency Tunable High Power Submillimeter Wave Source.

高功率毫米波管是聚变等离子体研究中用于电子回旋共振加热和等离子体诊断的重要器件。在大型聚变装置中，尤其需要研制波长更短、可达亚毫米波、宽频带频率可调的电子管。本项目的重点是研究在高转换效率的潘尼奥管中实现频率可调谐的回波运转和实现较短波长产生的谐波回旋运转。我们已经设计和制造了几个试管，用于在未来的半离子加速器开发中对上述能力进行实验研究。本课题的研究成果如下。在自谐振管中实验获得了72%的电子效率。回旋快波管的效率值最高。在反向波管中获得了8~12 GHz的连续调谐频率。这是首次在回旋快波管中进行的实验研究。在高次回旋加速器实验管中首次实现了二次回旋加速器的高次谐波运行，实验还在继续探索高次谐波下的更高效率运行。为了将频率范围扩展到100 GHz，设计并制作了一种短毫米波测试管。实验将于1991年初开始。

High power millimeter wave tubes are great important devices in fusion plasma researches for the electron cyclotron resonance heating and plasma diagonostics. The development of tube with shorter wavelength up to submillimeter wave range and wide band frequency tunability is especially required in large fusion devices. This project is focussed to investigate the backward wave operation for the frequency tunability and the harmonic cyclotron operation for the shorter wavelength generation in the peniotron tube with a high conversion efficiency. We have designed and fabricated several test tubes to investigate experimentally above capabilities in future peniotron development. Research results in this project are as follows.1. The electronic efficiency of 72% was experimentally obtained in the auto-resonant peniotron test tube. The value of efficiency is the highest in the cyclotron fast wave tube.2. The continuous frequency tuning with wide band ranging from 8 to 12GHz was obtained in the backward wave peniotron test tube. The result is the first experimental investigation in the cyclotron fast wave tube.3. The 2nd cyclotron harmonic operation was first demonstrated in the high cyclotron harmonic peniotron test tube and the experiments are still continuing to investigate higher efficiency operation at the high cyclotron harmonics.4. A short millimeter wave test tube was designed and fabricated to extend the frequency range to 100GHz. Experiments will be started at the beginning in 1991.