Journal of Fusion Energy

, Volume 34, Issue 4, pp 721–726 | Cite as

Efficiency Enhancement of a 170 GHz Confocal Gyrotron Traveling Wave Tube

  • Youwei Yang
  • Sheng Yu
  • Yinghui Liu
  • Tianzhong Zhang
  • Yanyan Zhang
  • Qixiang Zhao
Original Research


Confocal gyrotron traveling wave tube (gyro-TWT) is a novel gyrotron amplifier capable of operating in higher order modes while generating high power at the same time. Confocal gyro-TWT suppresses lower-order modes at the cost of reduction of efficiency. According to the characteristics of confocal system, in this paper, we theoretically design a special magnetron injection gun (MIG) for a 170 GHz confocal gyro-TWT, and then compare it with the traditional MIG. The efficiency is found to be as high as 33 %, deservedly higher than the traditional less than 10 %. The output power increases trebly accordingly.


Confocal Gyro-TWT Efficiency Special MIG 



This work is supported in part by the national Basic Research Program under Grant 2014 CB33980 and in part by the national Natural Science Foundation of China under Grant 61231005.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Youwei Yang
    • 1
  • Sheng Yu
    • 1
  • Yinghui Liu
    • 1
  • Tianzhong Zhang
    • 1
  • Yanyan Zhang
    • 1
  • Qixiang Zhao
    • 1
  1. 1.Terahertz Science and Technology Research CenterUniversity of Electronic Science and Technology of ChinaChengduPeople’s Republic of China

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