Optimization of relativistic backward wave oscillator with nonuniform slow wave structure and a resonant reflector
Abstract
This letter optimizes synchronously 18 parameters of a relativistic backward wave oscillator with nonuniform slow wave structure (SWS) and a resonant reflector by using the parallel genetic algorithms and particleincell simulation. The optimization results show that the generation efficiency of microwave from the electron beam has increased 32% compared to that of the original device. After optimization, the electromagnetic mode propagating in the resonant changes from the original TM{sub 020} mode of reflector to higherorder TM{sub 021} mode, which has a high reflection coefficient in a broader frequency range than that of the former. The modulation of current inside the optimized device is much deeper than that in the original one. The product of the electric field and current is defined. Observing this product, it is found that the interaction of the electron beam with the electromagnetic wave in the optimized device is much stronger than that in the original device, and at the rear part of SWS of the optimized device, the electron beam dominantly gives out the energy to the electromagnetic wave, leading to the higher generation efficiency of microwave than that of the original device.
 Authors:
 Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049 (China)
 (China)
 Northwest Institute of Nuclear Technology, P.O. Box 6912, Xi'an 710024 (China)
 Publication Date:
 OSTI Identifier:
 22408038
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ALGORITHMS; COMPUTERIZED SIMULATION; CURRENTS; ELECTRIC FIELDS; ELECTRON BEAMS; FREQUENCY RANGE; INTERACTIONS; MICROWAVE RADIATION; MODULATION; OPTIMIZATION; OSCILLATORS; REFLECTION; RELATIVISTIC RANGE
Citation Formats
Chen, Zaigao, Wang, Jianguo, Northwest Institute of Nuclear Technology, P.O. Box 6912, Xi'an 710024, and Wang, Yue. Optimization of relativistic backward wave oscillator with nonuniform slow wave structure and a resonant reflector. United States: N. p., 2015.
Web. doi:10.1063/1.4906896.
Chen, Zaigao, Wang, Jianguo, Northwest Institute of Nuclear Technology, P.O. Box 6912, Xi'an 710024, & Wang, Yue. Optimization of relativistic backward wave oscillator with nonuniform slow wave structure and a resonant reflector. United States. doi:10.1063/1.4906896.
Chen, Zaigao, Wang, Jianguo, Northwest Institute of Nuclear Technology, P.O. Box 6912, Xi'an 710024, and Wang, Yue. 2015.
"Optimization of relativistic backward wave oscillator with nonuniform slow wave structure and a resonant reflector". United States.
doi:10.1063/1.4906896.
@article{osti_22408038,
title = {Optimization of relativistic backward wave oscillator with nonuniform slow wave structure and a resonant reflector},
author = {Chen, Zaigao and Wang, Jianguo and Northwest Institute of Nuclear Technology, P.O. Box 6912, Xi'an 710024 and Wang, Yue},
abstractNote = {This letter optimizes synchronously 18 parameters of a relativistic backward wave oscillator with nonuniform slow wave structure (SWS) and a resonant reflector by using the parallel genetic algorithms and particleincell simulation. The optimization results show that the generation efficiency of microwave from the electron beam has increased 32% compared to that of the original device. After optimization, the electromagnetic mode propagating in the resonant changes from the original TM{sub 020} mode of reflector to higherorder TM{sub 021} mode, which has a high reflection coefficient in a broader frequency range than that of the former. The modulation of current inside the optimized device is much deeper than that in the original one. The product of the electric field and current is defined. Observing this product, it is found that the interaction of the electron beam with the electromagnetic wave in the optimized device is much stronger than that in the original device, and at the rear part of SWS of the optimized device, the electron beam dominantly gives out the energy to the electromagnetic wave, leading to the higher generation efficiency of microwave than that of the original device.},
doi = {10.1063/1.4906896},
journal = {Physics of Plasmas},
number = 1,
volume = 22,
place = {United States},
year = 2015,
month = 1
}

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