High-power gyrotron traveling-wave amplifier with distributed wall losses and attenuating severs

Journal Article · Fri Apr 15 00:00:00 EDT 2005 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.1878752· OSTI ID:20736533

Yeh, Y S; Shin, Y Y; You, Y C; Chen, L K ^[1]

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1. Department of Electrical Engineering, Southern Taiwan University of Technology, Tainan, Taiwan (China)

Distributed-loss gyrotron traveling-wave amplifiers (gyro-TWTs) with high-gain, broadband, and millimeter-wave capabilities have been demonstrated. Most structures with distributed wall losses are stabilized in gyro-TWTs that operate at low beam currents. Attenuating severs are added to the interaction circuit of a distributed-loss gyro-TWT to prevent high beam currents that result in mode competition. Simulation results show that gyrotron backward-wave oscillations (gyro-BWOs) are not effectively suppressed by the lossy section; in contrast, the severed sections can effectively enhance the start-oscillation threshold of gyro-BWOs in the proposed gyro-TWT. Meanwhile, localized reflective oscillations seem not to occur in the gyro-TWT unless it operates at a high magnetic field or with a high interaction length. The stable gyro-TWT, operating in the low-loss TE{sub 01} mode, is predicted to yield a peak output power of 405 kW at 33 GHz with an efficiency of 20%, a saturated gain of 77 dB and a 3 dB bandwidth of 2.5 GHz for a 100 kV, 20 A electron beam with an axial velocity spread of {delta}v{sub z}/v{sub z}=5%.

• OSTI ID: 20736533
• Journal Information: Physics of Plasmas, Vol. 12, Issue 4; Other Information: DOI: 10.1063/1.1878752; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BEAM CURRENTS
ELECTRON BEAMS
GHZ RANGE 01-100
MICROWAVE AMPLIFIERS
TRAVELLING WAVES