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Title: Influence of a falling edge on high power microwave pulse combination

Abstract

This paper presents an explanation of the influence of a microwave falling edge on high-power microwave pulse combination. Through particle-in-cell simulations, we discover that the falling edge is the driving factor that limits the output power of the combined pulses. We demonstrate that the space charge field, which accumulates to become comparable to the E-field at the falling edge of the former pulse, will trap the electrons in the gas layer and decrease its energy to attain a high ionization rate. Hence, avalanche discharge, caused by trapped electrons, makes the plasma density to approach the critical density and cuts off the latter microwave pulse. An X-band combination experiment is conducted with different pulse intervals. This experiment confirms that the high density plasma induced by the falling edge can cut off the latter pulse, and that the time required for plasma recombination in the transmission channel is several microseconds. To ensure a high output power for combined pulses, the latter pulse should be moved ahead of the falling edge of the former one, and consequently, a beat wave with high peak power becomes the output by adding two pulses with normal amplitudes.

Authors:
;  [1];  [2];  [1]; ;  [3]
  1. Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei 230027 (China)
  2. (China)
  3. Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China)
Publication Date:
OSTI Identifier:
22600048
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLITUDES; COMPARATIVE EVALUATIONS; IONIZATION; LAYERS; MICROWAVE RADIATION; PARTICLES; PEAK LOAD; PLASMA DENSITY; PULSES; RECOMBINATION; SIMULATION; SPACE CHARGE; TRAPPED ELECTRONS

Citation Formats

Li, Jiawei, Huang, Wenhua, Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024, Zhu, Qi, Xiao, Renzhen, and Shao, Hao. Influence of a falling edge on high power microwave pulse combination. United States: N. p., 2016. Web. doi:10.1063/1.4955327.
Li, Jiawei, Huang, Wenhua, Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024, Zhu, Qi, Xiao, Renzhen, & Shao, Hao. Influence of a falling edge on high power microwave pulse combination. United States. doi:10.1063/1.4955327.
Li, Jiawei, Huang, Wenhua, Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024, Zhu, Qi, Xiao, Renzhen, and Shao, Hao. Fri . "Influence of a falling edge on high power microwave pulse combination". United States. doi:10.1063/1.4955327.
@article{osti_22600048,
title = {Influence of a falling edge on high power microwave pulse combination},
author = {Li, Jiawei and Huang, Wenhua and Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 and Zhu, Qi and Xiao, Renzhen and Shao, Hao},
abstractNote = {This paper presents an explanation of the influence of a microwave falling edge on high-power microwave pulse combination. Through particle-in-cell simulations, we discover that the falling edge is the driving factor that limits the output power of the combined pulses. We demonstrate that the space charge field, which accumulates to become comparable to the E-field at the falling edge of the former pulse, will trap the electrons in the gas layer and decrease its energy to attain a high ionization rate. Hence, avalanche discharge, caused by trapped electrons, makes the plasma density to approach the critical density and cuts off the latter microwave pulse. An X-band combination experiment is conducted with different pulse intervals. This experiment confirms that the high density plasma induced by the falling edge can cut off the latter pulse, and that the time required for plasma recombination in the transmission channel is several microseconds. To ensure a high output power for combined pulses, the latter pulse should be moved ahead of the falling edge of the former one, and consequently, a beat wave with high peak power becomes the output by adding two pulses with normal amplitudes.},
doi = {10.1063/1.4955327},
journal = {Physics of Plasmas},
number = 7,
volume = 23,
place = {United States},
year = {Fri Jul 15 00:00:00 EDT 2016},
month = {Fri Jul 15 00:00:00 EDT 2016}
}
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