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Chinese Physics B 2024年第3期33卷 480-487页

作者：王超刘佳苌磊卢凌峰张世杰周帆涛 State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqing 400044China Shanghai institute of Space Propulsion Shanghai 201112China Southwestern institute of Physics Chengdu 610041China

This paper deals with wave propagation and power coupling in blue-core helicon plasma driven by various antennas and *** is found that compared to non-blue-core mode,for blue-core mode,the wave can propagate in the core region,and it decays sharply outside the *** power absorption is lower and steeper in radius for blue-core *** the effects of antenna geometry for blue-core mode,it shows that half helix antenna yields the strongest wave field and power absorption,while loop antenna yields the ***,near axis,for antennas with m=+1,the wave field increases with axial *** the core region,the wave number approaches to a saturation value at much lower frequency for non-blue-core mode compared to blue-core *** total loading resistance is much lower for blue-core *** findings are valuable to understanding the physics of blue-core helicon discharge and optimizing the experimental performance of blue-core helicon plasma sources for applications such as space propulsion and material treatment.

关键词： helicon plasma helicon wave helicon discharge radio frequency plasma source

DESIGN AND ANALYSIS OF MULTI-STEP AMPLITUDE QUANTIZATION WEIGHTED 2-D SOLID-STATE ACTIVE PHASED ARRAY antennas

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Journal of Electronics(China) 1994年第1期11卷 71-78页

作者：高铁李建新郭燕昌 Nanjing Research institute of Electronic Technology Nanjing 210013Nanjing Research Institute of Electronic Technology Nanjing 210013Nanjing Research Institute of Electronic Technology Nanjing 210013

An aperture design technique using multi-step amplitude quantization for two-dimensional solid-state active phased arrays to achieve low sidelobe is described. It can be applied to antennas with arbitrary complex aperture. Also, the gain drop and sidelobe degradation due to random amplitude and phase errors and element (or T/R module) failures are investigated.

关键词： Solid-state active phased array antenna Multi-step amplitude quantization Low sidelobe Amplitude and phase errors Gain loss Failure

Review of Large Spacecraft Deployable Membrane Antenna Structures

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1447-1459页

作者： Zhi-Quan Liu Hui Qiu Xiao Li Shu-Li Yang Beijing institute of Spacecraft System Engineering China Academy of Space Technology Beijing 100094 China

The demand for large antennas in future space missions has increasingly stimulated the development of deployable membrane antenna structures owing to their light weight and small stowage volume. However, there is little literature providing a comprehensive review and comparison of different membrane antenna structures. Space-borne membrane antenna structures are mainly classified as either parabolic or planar membrane antenna structures. For parabolic membrane antenna structures, there are five deploying and forming methods, including inflation, inflation-rigidization, elastic ribs driven, Shape Memory Polymer （SMP）-inflation, and electrostatic form- ing. The development and detailed comparison of these five methods are presented. Then, properties of membrane materials （including polyester film and polyimide film） for parabolic membrane antennas are compared. Additionally, for planar membrane antenna structures, frame shapes have changed from circular to rectangular, and different ten- sioning systems have emerged successively, including single Miura-Natori, double, and multi-layer tensioning systems. Recent advances in structural configurations, tensioning system design, and dynamic analysis for planar membrane antenna structures are investigated. Finally, future trends for large space membrane antenna structures are pointed out and technical problems are proposed, including design and analysis of membrane structures,materials and processes, membrane packing, surface accuracy stability, and test and verification technology. Through a review of large deployable membrane antenna structures, guidance for space membrane-antenna research and applications is provided.

关键词： Membrane antenna. Parabolic Plane.Tensioning system Dynamics

Simulations of first-orbit losses of neutral beam injection(NBI)fast ions on EAST

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Plasma Science and Technology 2020年第8期22卷 49-62页

作者： Xingyuan XU Yingfeng XU Xiaodong ZHANG Youjun HU Lei YE Xiaotao XIAO institute of Plasma Physics Chinese Academy of SciencesHefei 230031People's Republic of China

Simulations of first-orbit losses of neutral beam injection(NBI)fast ions in the EAST tokamak have been studied in detail by using the orbit-following code GYCAVA and the NBI code *** ion losses with the wall boundary are smaller than those with the last closed flux surface *** contrast to heat loads on the wall without radio frequency wave(RFW)antennas,heat loads on the wall with RFW antennas are distributed more locally near the RFW *** direction of the toroidal magnetic field dramatically affects the final positions of lost fast ions,which is related to the magnetic *** numerical results on heat loads of beam ions corresponding to different toroidal magnetic fields are qualitatively consistent with the experimental *** ion losses increase with the beam energy for the co-current NBIs and the counter-perpendicular *** have studied the behavior of fast ions produced by a small section neutral beam(beamlet)by using the numerical tool *** distributions of the loss fraction of beamlet fast ions peaked near the edge of the beam section for the counter-current NBIs,and they are related to the injection *** indicates that the first-orbit losses can be reduced by changing the shape of beam cross section.

关键词： neutral beam first-orbit loss GYCAVA

Laser Interferometer Used for Satellite-Satellite Tracking: an On-Ground Methodological Demonstration

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Chinese Physics Letters 2012年第7期29卷 295-297页

作者： LI Yu-Qiong LUO Zi-Ren LIU He-Shan DONG Yu-Hui JIN Gang National Microgravity Laboratory(NML) Institute of MechanicsChinese Academy of SciencesBeijing 100190

A Chinese satellite gravity mission called SAGM (Space Advanced Gravity Measurements) is now taken into *** meet its designed requirement,the measurement precision of the laser ranging system used to measure the inter-satellite distance change has to be better than l00nm/Hz1/2 within a broad bandwidth from 0.1mHz to *** equal arm heterodyne Mach-Zehnder interferometer has been built on ground to demonstrate the measurement principle of a laser ranging system,which potentially can be used for both SAGM and future GW (gravitational wave) space *** of the equal arm length,the laser frequency noise has been significantly suppressed in the ***,the sensitivity better than 1nm/Hz1/2 in a frequency range of 0.15 mHz-0.375 Hz has been *** result shows that the proposed methodology has very promising feasibility to meet the requirements of SAGM and of GW space antennas as well.

关键词： interferometer antennas heterodyne

Design of improved compact decoupler based on adjustable capacitor for EAST-ICRF antenna

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Plasma Science and Technology 2022年第1期24卷 177-182页

作者： Gen CHEN Yuzhou MAO Shuai YUAN Yanping ZHAO Hua YANG Xinjun ZHANG Chengming QIN Yan CHENG Yongsheng WANG institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China

The Ion Cyclotron Radio Frequency(ICRF)heating antenna on EAST adopts a decoupling device to constrain power coupling among the radiation straps,which was discovered shortcomings such as long size,poor contact,and *** order to improve these weak points,a new type decoupler with terminal-loaded tunable capacitor is designed to replace the previous *** the capability of the tunable admittance parameters of decoupler,the withstand voltage of the capacitor is the most significant consideration for working under high ***,the theoretical analysis carefully elaborates the capacitor withstand voltage,and the detailed analytical equations and criteria for design are *** the comparative analysis of theoretical calculation and 3D simulation results,the decoupler design scheme is *** capacitor-loaded decoupler has been successfully adopted for ICRF antenna at port N on EAST,and achieved the optimization of adjacent port isolation from-22 to-58 dB at 37 MHz without plasma to restrict mutual *** new design of the decoupler has greatly improved its compactness and automatic adjustment performance,and could be good solution for the decoupling network of ICRF antennas.

关键词： decoupler ICRF adjustable capacitor EAST

An overview of multi-antenna technologies for space-ground integrated networks

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Science China Earth Sciences 2016年第12期59卷 1-18页

作者： Lei GAO Shuo ZHANG Ziyao LIU Jinyong LIN Shuai WANG Chengwen XING National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing 100854China Beijing Aerospace Automatic Control institute Beijing 100854China School of Information Science and Electronics Beijing Institute of TechnologyBeijing 100081China

Multi-antenna technologies have already achieved a series of great successes in the development of information networks. For future space-ground integrated networks(SGINs), the traditional various kinds of separated information networks will converge to a whole fully connected information network to provide more flexible and reliable services on a world scale. Regarding their great successes in existing systems, multiantenna technologies will be of critical importance for the realization of SGINs and multi-antenna technologies are definitely one of the most important enabling technologies for future converged SGINs. In this article, a comprehensive overview on multi-antenna technologies is given. We first investigate multi-antenna technologies from a theoretical viewpoint. It is shown that we can understand multi-antenna technologies in a general and unified point of view. This fact has two-fold meanings. First, the research on multi-antennas can help us understand the relationships between different technologies e.g., OFDMA, CDMA, etc. On the other hand,multi-antenna technologies are easy to integrate into various information systems. Following that, we discuss in depth the potentials and challenges of the multi-antenna technologies on different platforms and in different applications case by case. More specifically, we investigate spaceborne multi-antenna technologies, airborne multi-antenna technologies, shipborne multi-antenna technologies, etc. Moreover, the combinations of multiantenna technologies with other advanced wireless technologies e.g., physical layer network coding, cooperative communication, etc., are also elaborated.

关键词： MIMO multi-antenna technologies signal processing space-ground integrated networks satellite networks terrestrial networks

RF design optimization for the SHINE 3.9 GHz cavity

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Nuclear Science and Techniques 2020年第7期31卷 97-105页

作者： Yu-Xin Zhang Jin-Fang Chen Dong Wang Shanghai institute of Applied Physics Chinese Academy of SciencesShanghai 201204China ShanghaiTech University Shanghai 201210China Shanghai Advanced Research institute Chinese Academy of SciencesShanghai 201204China

The Shanghai high-repetition-rate XFEL and extreme light facility(SHINE)under construction is designed to be one of the most advanced free electron laser(FEL)facilities in the *** main part of the SHINE facility is an 8 GeV superconducting Linac operating in continuous wave(CW)*** Linac consists of seventy-five 1.3 GHz and two 3.9 GHz *** on the design and experience of 3.9 GHz cavities in the European X-ray free electron laser(E-XFEL)and the Linac coherent light source-II(LCLS-II)projects,we optimize the SHINE 3.9 GHz cavity design to adapt it for CW mode *** this paper,we present a particular redesign of the end group for the SHINE 3.9 GHz superconducting cavity that includes a redesign of the end cell and beam pipe to shift away the potentially troublesome lowest highorder modes(HOMs),a modification of the main coupler antenna,and a tuning of the HOM notch filter to meet the cavity *** losses calculations on the HOM coupler antennas show that the overheating on the inner conductor at the operating mode is diminished ***,we have also studied the HOMs to ensure there are no dangerously trapped modes in the optimized cavity design.

关键词： cavity antenna tuning

Frequency reconfigurable antenna actuated by inflated triangular structure:Design and analysis

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Chinese Journal of Aeronautics 2023年第5期36卷 280-285页

作者： Jiaming GUO Xinghan QIU Jiawei ZHANG Lamei ZHANG Changguo WANG School of Astronautics Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin 150001China School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

This paper proposes a frequency reconfigurable triangular antenna actuated by an inflated triangular *** open path antenna is transformed from an open type to a closed structure by *** structures are easy to manufacture by fusing 2 inextensible membranes together along a defined pattern of ***,the prediction of their deployed shape remains a *** solve the pattern changed problem,guided by geometric analyses and local buckle characteristics,the inflated triangular structure has been designed and verified by experiment and *** the process of transformation of the antenna,the resonant frequency of the antenna is changed because this frequency is determined by the conformational *** resonant frequency changes from GHz to kHz when the design of initial structure sizes is from millimeter to *** measured peak gains,the frequency,and the radiation direction are also reconfigurable by the initial ***,the reconfigurable resonator array is presented,which is coupled to electric fields to absorb all incident *** this work,the changed pattern design by inflating is applied to the antenna design,and its frequency reconfigurability is *** the electricity performance analysis of the reconfigurable antenna,precise manufacturing will be possible and provide guidance for manufacturing frequency reconfigurable antennas.

关键词： Free kink design Frequency Reconfigurable Antenna(FRA) Inflated Return losses Thin film

Properties of terahertz wave generated by the metallic carbon nanotube antenna

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Chinese Optics Letters 2008年第10期6卷 770-772页

作者：王玥吴群 School of Electronics and Information Technology Harbin Institute of TechnologyHarbin 150001 Department of Electrical Science and TechnologyHarbin University of Science and TechnologyHarbin 150080 School of Electronics and Information Technology Harbin Institute of TechnologyHarbin 150001

The properties of terahertz （THz） radiation pulses emitted by a metallic, large aspect ratio carbon nanotube antenna have been studied both in the THz waveforms and field distribution. The peak THz field up to 2.66 and 1.26 kV/cm are observed at the probe points. The proposed antenna is designed to operate for dual frequency applications from 2.36 to 2.58 THz and from 7.27 to 7.5 THz for less than -10 dB return loss.

关键词： antennas Aspect ratio Nanocomposites Nanostructured materials Nanostructures Nanotubes