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The evolution of fast electronics

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Chinese Science Bulletin 2010年第23期55卷 2479-2488页

作者： AN Qi WANG YanFang fast Electronics Laboratory University of Science & Technology of China Hefei 230026 China

This paper analyzes the process from gestation to maturity of fast electronics,describes the three-level relations formed in the development of fast electronics,*** of application,technique and theory,and summarizes in brief the progresses in simulation of electromagnetic fields,high-speed parallel sampling,and research of time *** results of fast electronics in national economy and national major science projects are also introduced.

关键词：电子技术应用快速电子快电子学应用程序大肠杆菌高速并行时间抖动科技项目

Commissioning progress of the fast

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Science China(Physics,Mechanics & Astronomy) 2019年第5期62卷 3-24页

作者： Peng Jiang YouLing Yue HengQian Gan Rui Yao Hui Li GaoFeng Pan JingHai Sun DongJun Yu HongFei Liu NingYu Tang Lei Qian JiGuang Lu Jun Yan Bo Peng ShuXin Zhang QiMing Wang Qi Li Di Li CAS Key Laboratory of fast National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences

The Five-hundred-meter Aperture Spherical radio Telescope(fast) was completed with its main structure installed on September 25, 2016, after which it entered the commissioning phase. This paper aims to introduce the commissioning progress of the fast over the past two years. To improve its operational reliability and ensure effective observation time, fast has been equipped with a real-time information system for the active reflector system and hierarchical commissioning scheme for the feed support system, which ultimately achieves safe operation of the two systems. For meeting the high-performance indices, a highprecision measurement system was set up based on the effective control methods that were implemented for the active reflector system and feed support system. Since the commissioning of the fast, a low-frequency ultra-wideband receiver and 19-beam1.05-1.45 GHz receiver have been mainly used. Telescope efficiency, pointing accuracy, and system noise temperature were completely tested and ultimately achieved the acceptance indices of the telescope. The fast has been in the process of national acceptance preparations and has begun to search for pulsars. In the future, it will still strive to improve its capabilities and expand its application prospects.

关键词： radio telescopes and instrumentation astronomical observations radio wave receivers algorithms and implementation control systems

Extragalactic HⅠSurvey with fast:First Look at the Pilot Survey Results

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Research in Astronomy and Astrophysics 2022年第6期22卷 215-233页

作者： Jiangang Kang Ming Zhu Mei Ai Haiyang Yu Chun Sun National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of fast National FASTNational Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Beijing Normal University Beijing 100875China

We present the first data release of HⅠsources extracted from a pilot extragalactic survey using the Five-hundredmeter Aperture Spherical radio Telescope(fast).We extracted sources from three-dimensional(3D)spectral data cubes datacubes to perform interactive searching and computing,yielding global parameters for each source,extending redshift ranges of HⅠemission up to z=0.04.A total of 544 extragalactic HⅠsources has been detected by the pilot fast HⅠdrift scan survey covering part of the sky region in R.A.(***α)and decl.(***δ)range 00^(h)47^(m)6.5;(2)61 sources with 5.1■S/N■6.5;(3)28 sources with relatively poor baselines;(4)33 sources that are partly masked by strong radio frequency interferences(RFIs).In addition,we find 16 HⅠsources that have not been matched with any counterparts in the existing galaxy *** data release can provide guidance for the future extragalactic HⅠsurvey with fast.

关键词： galaxies formation-radio lines galaxies-surveys-galaxies distances and redshifts-radiation dynamics-galaxies evolution

Development of wideband orthomode transducers for fast cryogenic receiver system

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Research in Astronomy and Astrophysics 2020年第5期20卷 137-147页

作者： Jin Fan Kai Zhu Heng-Qian Gan Peng Jiang Jian Yang Yang Cao Hong-Fei Liu Hang Zhang Ming-Lei Guo Xiang-Wei Shi CAS Key Laboratory of fast the National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Chalmers University of TechnologyGothenburgSweden

This paper describes the design,construction,and performance of the wideband orthomode transducers(OMTs)for the L-(1.2–1.8 GHz),the S-(2–3 GHz)and the P-(0.56–1.12 GHz)band receiver systems of the Five-hundred-meter Aperture Spherical radio Telescope(fast).These OMTs operate at the cryogenic temperature of 70 K to reduce their thermal noise contribution to the receiver *** development on the fast L-and S-band quad-ridged waveguide(QRWG)OMTs is carried out based on the theoretical mode *** view of the miniaturization of fast cryogenic receiver system at P-band,a novel wideband compact bowtie dipole OMT is designed with an octave bandwidth as well as a length of only quarter *** proposed L-,S-and P-band OMTs are designed and optimized by using Ansys High Frequency Structure Simulator(HFSS),and then manufactured,tested at room *** of fast cryogenic receiver system noise is also performed with the L-,S-and P-band OMTs *** measured results fully comply with the design specifications.

关键词： fast instruments telescopes

An open-loop control algorithm of the active reflector system of fast

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Research in Astronomy and Astrophysics 2020年第5期20卷 93-102页

作者： Hui Li Peng Jiang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of fast National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

An open-loop control algorithm is put forward for continuous paraboloid deformation of the active reflector system of the Five-hundred-meter Aperture Spherical radio Telescope(fast).The method is based on a calibration database and interpolation in 2D spatial domain and temperature domain,*** is completely independent of real-time measurement of cable nodes so that it has advantage of working all-weather and no additional electro-magnetic interference(EMI).Furthermore,its control accuracy can be effectively improved via reasonable layout of the calibrated paraboloids and increasing calibration *** deformation safety is considered via calibration as *** its control accuracy is also confirmed via site measurements of paraboloid deformations.

关键词： Astronomical instrumentation:methods and techniques methods:data analysis methods:numerical

A motion planning algorithm for the feed support system of fast

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Research in Astronomy and Astrophysics 2020年第5期20卷 117-126页

作者： Rui Yao Peng Jiang Jing-Hai Sun Dong-Jun Yu Chun Sun National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of fast National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

The paper relates to a motion planning algorithm for the feed support system of the Five-hundred-meter Aperture Spherical radio Telescope(fast).To enhance the stability of the feed support system,the start/termination planning segments are adopted with an acceleration and deceleration *** source switching planning adopts a combination of a line segment and focal segment to realize stable control of the feed support ***,during the observation trajectory,a transition segment which is not used for observation data is planned with a required *** an example simulation,a smooth change is realized via the motion planning algorithm and presented in this paper.

关键词： fast radio telescope motion planning

Prognostics and health management of fast cable-net structure based on digital twin technology

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Research in Astronomy and Astrophysics 2020年第5期20卷 109-116页

作者： Qing-Wei Li Peng Jiang Hui Li National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of fast National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

The Five-hundred-meter Aperture Spherical radio Telescope(fast)will be fully commissioned later in *** commissioned,operation and maintenance of fast will be the most prominent *** unique working mode of active shape-changing of fast cable-net structure makes the traditional maintenance way,which combines routine inspection with preventive maintenances not only expensive,but also unable to effectively avoid potential risks in ***,it is necessary to develop an economical and reliable operation/maintenance technology for fast cable-net *** this paper,a Prognostics and Health Management(PHM)system is proposed based on the advanced Digital Twin(DT)*** the finite element analysis of DT model,the current safety status of fast cablenet is evaluated,and the fatigue life of components in the cable-net is *** Condition-Based Maintenance(CBM)of fast cable-net structure can be *** PHM system described in this paper can effectively guarantee the healthy and safe operation of the fast cable-net structure,greatly improve the maintenance efficiency and reduce the cost for maintenance works.

关键词： telescopes astronomical instrumentation methods and techniques methods:analytical methods:data analysis

fast:The Five-Hundred-Meter Aperture Spherical Radio Telescope

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Engineering 2023年第9期28卷 21-25页

作者： Peng Jiang Hengqian Gan Rui Yao Jinghai Sun Jiguang Lu Dongjun Yu Hui Li Jinglong Yu Bin Dong Xiaoming Chai Jianing Yin Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550025China fast Operation and Development Center National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

In the 90 years since its inception,radio astronomy has become the setting of almost all major astronomical discoveries and a hothouse for Nobel Prizes in *** a result,countries all over the world have actively explored new engineering concepts to build large-aperture radio *** by their self-weight and wind load,100 m radio telescopes are regarded as the maximum limit of traditional radio *** perspective allowed the Arecibo 305 m telescope—built by Cornell University in the United States in 1963—to dominate the field for more than half a *** this period,scholars have been exploring how to further expand their horizons in order to make a breakthrough in the problem of the universe.

关键词： breakthrough telescope horizon

Design and optimization of cross bow-tie dipole feed with cavity for fast

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Research in Astronomy and Astrophysics 2020年第5期20卷 132-136页

作者： Jing-Long Yu You-Ling Yue Jian-Bin Li National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of fast National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

A cross bow-tie dipole feed with cavity and symmetrical E and H plane pattern is presented for the Five hundred-meter Aperture Spherical radio Telescope(fast).In this paper we describe the design,optimization and simulation results of a wide-band cross dipole feed with cavity covering the frequency range from 300 MHz to 600 MHz for *** main goals of our design are to ensure that,(1)we cover the octave bandwidth,(2)the feed has symmetrical E and H plane pattern,and(3)the physical dimension is suitable for mounting it in the reserved position of the fast feed *** initial results indicate that we have met most of our design *** kind of feed had been equipped with the multi-beam receiver to carry out observation on the platform of fast cabin.

关键词： telescope feed bow-tie dipole cavity fast