Research on Magnetron Injection Gun with Curved Cathode for Megawatt-class Gyrotron Traveling Wave Tube

Li Jinshuai; Bao Mingming; Xu Yong; Cai Mao; Liu Luwei; Chen Jing; Yin Pengcheng; Cai Jinchi; Xu Jin; Lin Xiancai; Yue Lingna; Yin Hairong; Niu Xinjian; Liu Yinghui; Wei Yanyu

doi:10.11884/HPLPB202638.250209

Article Contents

Article Navigation > High Power Laser and Particle Beams > 2026 > Accepted Manuscript

Li Jinshuai, Bao Mingming, Xu Yong, et al. Research on Magnetron Injection Gun with Curved Cathode for Megawatt-class Gyrotron Traveling Wave Tube[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202638.250209

Citation:

Li Jinshuai, Bao Mingming, Xu Yong, et al. Research on Magnetron Injection Gun with Curved Cathode for Megawatt-class Gyrotron Traveling Wave Tube[J]. High Power Laser and Particle Beams. doi: 10.11884/HPLPB202638.250209

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Research on Magnetron Injection Gun with Curved Cathode for Megawatt-class Gyrotron Traveling Wave Tube

doi: 10.11884/HPLPB202638.250209

1.
School of Electronic Science and Engineering, Sichuan Provincial Institute for Vacuum Electronics, University of Electronic Science and Technology of China
2.
Seventh Military Representative Office of the Air Force Equipment Department stationed in Beijing area, Beijing 100086, China

Received Date: 2025-07-14
Accepted Date: 2025-10-28
Rev Recd Date: 2025-11-03

Available Online: 2025-11-15

Abstract

Abstract

Background
Gyrotron traveling wave tube (Gyro-TWT) is a vacuum electronic device with broad application prospects. Magnetron injection gun (MIG) is one of the core components of gyro-TWT, and its performance directly determines the success or failure of gyro-TWT. From the current research results on MIGs at home and abroad, it can be seen that the working voltage and current of existing MIGs are mostly low, and the velocity spread is generally high, which cannot meet the requirements of future megawatt-class gyro-TWT for MIG.
Purpose
In order to meet the requirement for MIG with high voltage, high current, and low electron beam velocity spread in the development of megawatt-class high-power gyro-TWT, this paper presents a novel design scheme for a single anode electron gun.
Methods
The novel electron gun scheme introduces a curved cathode structure to reduce the velocity spread of the electron beam, while effectively increasing the cathode emission band area and reducing the cathode emission density.
Results
The results of PIC simulation show that under the working conditions of 115 kV and 43 A, the designed electron gun has a transverse to longitudinal velocity ratio of 1.05, a velocity spread of 1.63%, and a guiding center radius of 3.41 mm. The thermal analysis results indicate that the MIG can heat the cathode to 1050 ℃ at a power of 76 W.
Conclusions
The simulation and thermal analysis results indicate that the designed MIG meets the design expectations and satisfies the requirements of high voltage, high current, and low electron beam velocity spread for megawatt level gyro-TWT.
- gyro-TWT,
- MIG,
- high power millimeter wave,
- curved cathode,
- velocity spread

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References(17)

References

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