关键词: 多载波/
微放电阈值/
微波部件/
粒子模拟
English Abstract
Particle simulation and analysis of threshold for multicarrier multipactor
Wang Xin-Bo1,2,Zhang Xiao-Ning1,
Li Yun2,
Cui Wan-Zhao2,
Zhang Hong-Tai2,
Li Yong-Dong1,
Wang Hong-Guang1,
Zhai Yong-Gui1,
Liu Chun-Liang1
1.Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China;
2.National Key Laboratory of Science and Technology on Space Microwave, Xi'an Institute of Space Radio Technology, Xi'an 710100, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant No.U1537211) and the Foundation of National Key Laboratory of Science and Technology on Space Microwave,China (Grant No.9140C530101150C53011).Received Date:08 April 2017
Accepted Date:12 May 2017
Published Online:05 August 2017
Abstract:The multicarrier multipactor is a phenomenon that can be observed in vacuum environment due to the effect of secondary electron emission. Accurate analysis of the threshold of multicarrier multipactor is crucial for the long-term reliability of high-power spaceborne microwave system, and therefore it has been attracting more and more interests in fields of high-power microwave community, plasma physics and aerospace engineering. Recently, a new mechanism of multicarrier multipactor, termed long-term multipactor, induced by sustained accumulation of residual electrons between successive envelope periods of multicarrier signals has received much attention. Comparing with the single-event multipactor induced by the electron accumulation inside a single envelop period, researchers tend to believe that the threshold of the long-term discharge should be lower. However, recent experimental results show an opposite conclusion. In this work, in order to investigate the contradiction between the experimental and theoretical studies on the thresholds of multicarrier multipactors, particle simulations are used to simulate the evolution process of the multicarrier multipactor under the same conditions and judgement criterion. The behavioral characteristics and occurrence condition for multicarrier multipactors, especially the single-event ones, are analyzed based on a power scanning analysis, and the conflicting results are effectively explained. Our simulations show that if the evolution process of a multipactor can be divided into three phases, i.e., establishment phase, critical phase and saturation phase, the experimental reflection coefficient can be corresponding to the reflection coefficient simulated in the critical phase. The simulation results indicate that the type of the multipactor discharge would depend on the configuration of multicarrier signals. For multicarrier signals with relatively narrow bandwidths, single-event multicarrier multipactors could occur in the first place at a lower threshold power. Therefore, the threshold of a long-term discharge is not necessarily lower than that of a single-event one. This conclusion is important for estimating and suppressing the multicarrier multipactors in the design of high-power spaceborne microwave components.
Keywords: multicarrier/
multipactor threshold/
microwave components/
particle simulation
