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Development of Satellite Communication 预览
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作者 Linjie Yao Guangxi Xu Haiqing Yang 《当前的电子和电信》 2019年第1期31-36,共6页
Satellite communication refers to the use of artificial earth satellites as a relay station to forward radio waves, between two or more earth stations in the communication. Satellite communications since 1945 developm... Satellite communication refers to the use of artificial earth satellites as a relay station to forward radio waves, between two or more earth stations in the communication. Satellite communications since 1945 development so far, greatly accelerating the process of social information. The research and use of our satellites began in the early 1970s. Satellite communication applications include applications in data transmission services, applications in mobile communication systems, applications in video broadcast services, and applications in interactive services such as telephony. With the advancement of satellite communication technology and the improvement of satellite communication capability, the application of satellite communication is becoming more and more extensive, and the service level is getting higher and higher. In today's rapid development of terrestrial communications, satellite communications in the development of the market despite the great diffi culties and risks, and even suff ered major setbacks, but because of its irreplaceable characteristics of the decision it is still to develop and application. Therefore, from the overall and long term, the future development prospects of satellite communications is still bright and beautiful. China's satellite communications development goals: good management, make good use of existing satellite communications systems, and actively develop new business, new markets, new systems and adhere to independent construction. 展开更多
关键词 SATELLITE COMMUNICATION SATELLITE Data Transmission SATELLITE MOBILE COMMUNICATION SATELLITE VIDEO BROADCASTING SATELLITE TELEPHONE Interaction
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A Global Seamless Hybrid Constellation Design Approach with Restricted Ground Supporting for Space Information Network 预览
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作者 Wei ZHANG Tao WU +1 位作者 Hong MA Guixin LI 《系统科学与信息学报:英文版》 CSCD 2019年第3期257-269,共13页
In space information networks, satellites are generally in high speed orbit motion. In order to obtain better spacial and temporal coverage performance, satellites should cooperate with each other as a constellation. ... In space information networks, satellites are generally in high speed orbit motion. In order to obtain better spacial and temporal coverage performance, satellites should cooperate with each other as a constellation. Previous works on constellations mainly focus on global seamless coverage using fewer satellites. However, like most countries, it is hard for China to build ground stations in overseas, and the geostationary Earth orbit position resource is scarce. In this paper, we investigate the constellation design problem with restricted ground supporting. We first proposes a 'backbone network + enhanced network' hybrid constellation design approach. Then a hybrid '4GEO+5IGSO' constellation is designed using the proposed approach, and the coverage performance of this constellation is analyzed in detail. Simulation results show the proposed approach can realize global seamless coverage only using a small number of satellites. Furthermore, the proposed hybrid constellation meets the coverage demand only relies on ground stations inside China. 展开更多
关键词 space information network CONSTELLATION design HYBRID CONSTELLATION GEO SATELLITE IGSO SATELLITE
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Latest Progress of the Chinese Meteorological Satellite Program and Core Data Processing Technologies 预览
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作者 Peng ZHANG Qifeng LU +9 位作者 Xiuqing HU Songyan GU Lei YANG Min MIN Lin CHEN Na XU Ling Sun Wenguang BAI Gang MA Di XIAN 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第9期1027-1045,共19页
In this paper,the latest progress,major achievements and future plans of Chinese meteorological satellites and the core data processing techniques are discussed.First,the latest three FengYun(FY)meteorological satelli... In this paper,the latest progress,major achievements and future plans of Chinese meteorological satellites and the core data processing techniques are discussed.First,the latest three FengYun(FY)meteorological satellites(FY-2H,FY-3D,and FY-4A)and their primary objectives are introduced Second,the core image navigation techniques and accuracies of the FY meteorological satellites are elaborated,including the latest geostationary(FY-2/4)and polar-orbit(FY-3)satellites.Third,the radiometric calibration techniques and accuracies of reflective solar bands,thermal infrared bands,and passive microwave bands for FY meteorological satellites are discussed.It also illustrates the latest progress of real-time calibration with the onboard calibration system and validation with different methods,including the vicarious China radiance calibration site calibration,pseudo invariant calibration site calibration,deep convective clouds calibration,and lunar calibration.Fourth,recent progress of meteorological satellite data assimilation applications and quantitative science produce are summarized at length.The main progress is in meteorological satellite data assimilation by using microwave and hyper-spectral infrared sensors in global and regional numerical weather prediction models.Lastly,the latest progress in radiative transfer,absorption and scattering calculations for satellite remote sensing is summarized,and some important research using a new radiative transfer model are illustrated. 展开更多
关键词 METEOROLOGICAL SATELLITE GEOLOCATION calibration and VALIDATION SATELLITE data ASSIMILATION RADIATIVE transfer model
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Study on Thermal Deformation Measurement of Optical RemoteSensing Satellite Platform Based on Machine Vision 预览
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作者 Jie Huang Chaolan You +3 位作者 Peng Hou Da Luo Xiangsen Kong Xin Fu 《哈尔滨工业大学学报:英文版》 EI CAS 2019年第5期72-78,共7页
To solve the special requirements of the high orbit optical remote sensing satellite for the thermal deformation of the platform the thermal deformation test and measurement scheme of the satellite platform is designe... To solve the special requirements of the high orbit optical remote sensing satellite for the thermal deformation of the platform the thermal deformation test and measurement scheme of the satellite platform is designed. Through the comparative analysis of test results the rationality of the thermal deformation design of the platform structure is verified. The results of thermal deformation measurement show that the maximum deformation of A camera mounting surface is 57.5〃 and the maximum deformation of B camera mounting surface points to 79.3〃 which can be used as the basis for thermal deformation prediction of satellite during the orbit operation. 展开更多
关键词 REMOTE SENSING SATELLITE thermal DEFORMATION METEOROLOGICAL SATELLITE
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星箭界面整星隔振设计及减振效果验证 预览
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作者 张群 邢建伟 +2 位作者 毕京丹 潘忠文 卫国 《航天器环境工程》 2019年第5期502-507,共6页
星箭界面减振设计对改善卫星发射时的动力学环境具有重要意义。文章设计串联式磁流变阻尼隔振平台和并联式黏滞阻尼隔振平台,并对这2种隔振平台基于某中型卫星模型开展整星系统级隔振性能的工程试验研究,通过减振特性对比分析评估它们... 星箭界面减振设计对改善卫星发射时的动力学环境具有重要意义。文章设计串联式磁流变阻尼隔振平台和并联式黏滞阻尼隔振平台,并对这2种隔振平台基于某中型卫星模型开展整星系统级隔振性能的工程试验研究,通过减振特性对比分析评估它们的减振效果。结果显示:串联式磁流变阻尼隔振平台3方向减振效果均较好,质量控制满足设计要求,但会改变系统固有频率;并联式黏滞阻尼隔振平台对系统结构质量和固有频率的影响均较小,x向减振效果较好,但y向、z向减振效果不理想,须进一步优化系统参数。研究结果可为整星隔振的实际工程应用提供依据。 展开更多
关键词 卫星 隔振设计 磁流变阻尼器 黏滞阻尼器 适配器 减振 试验研究
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基于虚拟仪器的卫星磁测试系统设计 预览
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作者 江浩 赵江萍 宋歌 《测控技术》 2019年第8期74-77,83,共5页
根据卫星刺磁测试及磁矩计算的需求,开发了一种基于虚拟仪器的磁测试系统。该系统利用NI PXI硬件平台,通过数字万用表和开关模块的配合,完成对磁通门传感器信号的采集,相对于并行采集可极大减少实际的通道数,降低硬件成本。在LahVIEW平... 根据卫星刺磁测试及磁矩计算的需求,开发了一种基于虚拟仪器的磁测试系统。该系统利用NI PXI硬件平台,通过数字万用表和开关模块的配合,完成对磁通门传感器信号的采集,相对于并行采集可极大减少实际的通道数,降低硬件成本。在LahVIEW平台下开发了测控软件,实现测试过程控制、磁矩计算及数据分析。该测试系统可用于对卫星、单机等航天器进行剩磁测试,为航天器的执道控制设计提供重要依据,具有可靠性高、使用方便灵活、开发周期短等优点。 展开更多
关键词 卫星 磁测试 虚拟仪器 数字万用表 测控软件
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Satellite-based Observational Study of the Tibetan Plateau Vortex:Features of Deep Convective Cloud Tops 预览
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作者 Yi-Xuan SHOU Feng LU +3 位作者 Hui LIU Peng CUI Shaowen SHOU Jian LIU 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第2期189-205,248共18页
In this study,an east-moving Tibetan Plateau vortex(TPV)is analyzed by using the ERA-5 reanalysis and multi-source satellite data,including FengYun-2E,Aqua/MODIS and CALIPSO.The objective is to demonstrate:(i)the usef... In this study,an east-moving Tibetan Plateau vortex(TPV)is analyzed by using the ERA-5 reanalysis and multi-source satellite data,including FengYun-2E,Aqua/MODIS and CALIPSO.The objective is to demonstrate:(i)the usefulness of multi-spectral satellite observations in understanding the evolution of a TPV and the associated rainfall,and(ii)the potential significance of cloud-top quantitative information in improving Southwest China weather forecasts.Results in this study show that the heavy rainfall is caused by the coupling of an east-moving TPV and some low-level weather systems[a Plateau shear line and a Southwest Vortex(SWV)],wherein the TPV is a key component.During the TPV’s life cycle,the rainfall and vortex intensity maintain a significant positive correlation with the convective cloud-top fraction and height within a 2.5 radius away from its center.Moreover,its growth is found to be quite sensitive to the cloud phases and particle sizes.In the mature stage when the TPV is coupled with an SWV,an increase of small ice crystal particles and appearance of ring-and U/V-shaped cold cloud-top structures can be seen as the signature of a stronger convection and rainfall enhancement within the TPV.A tropopause folding caused by ageostrophic flows at the upper level may be a key factor in the formation of ring-shaped and U/V-shaped cloud-top structures.Based on these results,we believe that the supplementary quantitative information of an east-moving TPV cloud top collected by multi-spectral satellite observations could help to improve Southwest China short-range/nowcasting weather forecasts. 展开更多
关键词 Tibetan Plateau VORTEX MULTI-SPECTRAL SATELLITE observations short-range/nowcasting weather forecasts cold U/V-shaped cloud top TROPOPAUSE folding
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Gene expression changes in dorsal root ganglia following peripheral nerve injury:roles in inflammation,cell death and nociception 预览
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作者 Sarah L. Martin Adam J. Reid +2 位作者 Alexei Verkhratsky Valerio Magnaghi Alessandro Faroni 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第6期939-947,共9页
Subsequent to a peripheral nerve injury,there are changes in gene expression within the dorsal root ganglia in response to the damage.This review selects factors which are well-known to be vital for inflammation,cell ... Subsequent to a peripheral nerve injury,there are changes in gene expression within the dorsal root ganglia in response to the damage.This review selects factors which are well-known to be vital for inflammation,cell death and nociception,and highlights how alterations in their gene expression within the dorsal root ganglia can affect functional recovery.The majority of studies used polymerase chain reaction within animal models to analyse the dynamic changes following peripheral nerve injuries.This review aims to highlight the factors at the gene expression level that impede functional recovery and are hence are potential targets for therapeutic approaches.Where possible the experimental model,specific time-points and cellular location of expression levels are reported. 展开更多
关键词 Gene expression polymerase chain reaction dorsal root GANGLIA INFLAMMATION NOCICEPTION cell death peripheral NERVE injury Schwann CELLS satellite GLIAL CELLS NERVE regeneration
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Monte Carlo simulations of the sensor head of imaging energetic electron spectrometer onboard a Chinese IGSO navigation satellite
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作者 ZOU Hong YE YuGuang +12 位作者 ZONG QiuGang CHEN HongFei LUO Lin ZHOU XuZhi CHEN XingRan HAO YiXin REN Jie WANG YongFu SHI WeiHong YU XiangQian JIA XiangHong XU Feng ZHANG XiaoXin 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第7期1169-1181,共13页
An imaging energetic electron spectrometer built by the Peking University team(BD-IES) onboard a Chinese navigation satellite in an inclined GEO orbit has been launched successfully in September 2015, which measures t... An imaging energetic electron spectrometer built by the Peking University team(BD-IES) onboard a Chinese navigation satellite in an inclined GEO orbit has been launched successfully in September 2015, which measures the spectra of the energetic electrons with the energy range of 50–600 keV in nine directions. In this study, Monte Carlo simulations of the BD-IES sensor head were performed using Geant4 and the corresponding characteristic responses to the isotropic energetic particles were derived. The effective geometric factors were estimated using the typical electron and proton spectra in the GEO orbit and the corresponding simulated sensor head responses. It was found that the average effective geometric factors of nine directions are close to the nominal geometric factors calculated with the traditional method, but the effective geometric factor decreases as the center energy of the energy channel decreases. The BD-IES sensor head also responses to the energetic protons, but the average contamination rate of all 72 channels is about 2%, which means that the proton contamination is acceptable. The spectra of the energetic electrons measured by BD-IES are derived using the effective geometric factors of the sensor head and are comparable with the spectra measured by the magnetic electron ion spectrometer(MagEIS) instrument onboard Van Allen Probes. 展开更多
关键词 Monte Carlo simulation pin-hole IMAGING system GEOMETRIC factor IMAGING ENERGETIC electron SPECTROMETER IGSO satellite
An empirical L-band scintillation model for a mid-latitude station,Weihai, China during the low solar activity period
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作者 PRIYADARSHI ,Shishir ZHANG Qing-He WANG Yong 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第7期1182-1190,共9页
Mid-latitude ionospheric scintillation has been studied in very poor proportion as compared to the equatorial and high latitude ionospheric scintillation. Mid-latitude ionospheric scintillations are often associated w... Mid-latitude ionospheric scintillation has been studied in very poor proportion as compared to the equatorial and high latitude ionospheric scintillation. Mid-latitude ionospheric scintillations are often associated with either day time photo-ionization or due to the storm enhanced density. Using the phase screen model and the wave propagation theory in random media, we have identified the orientation of the ionospheric irregularities over Weihai with the local geomagnetic field. Amplitude and phase scintillation data observed using global positioning system(GPS) scintillation receiver deployed at the mid-latitude observation station Weihai, have been used along with K-index derived from the horizontal magnetic field component of the local magnetometer. The proposed model uses the scintillation indices relationship with the local K-index. We identified the scintillation dependence over local K-index during geomagnetic quiet and disturbed condition. This dependence coefficient is used on the real scintillation data for modeling. The presented scintillation model has been validated by comparing it to the real observations. The co-relation coefficient is more than 90% during the disturbed as well as quiet geomagnetic conditions. 展开更多
关键词 mid-latitude IONOSPHERE scintillation GPS global navigation satellite systems (GNSS)
卫星星箭耦合力学分析模型二次缩聚方法 预览
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作者 谢伟华 尹家聪 +3 位作者 林勇文 董锴 陈曦 李正举 《航天器环境工程》 2019年第4期330-334,共5页
卫星的星箭耦合力学分析模型是利用模态综合法,从卫星有限元模型上直接缩聚得到的.目前的缩聚方法为一次缩聚方法,要求卫星本体以及天线、太阳电池阵等大部件的有限元模型都必须是未经缩聚的纯物理模型.为在无法获得大部件物理模型的情... 卫星的星箭耦合力学分析模型是利用模态综合法,从卫星有限元模型上直接缩聚得到的.目前的缩聚方法为一次缩聚方法,要求卫星本体以及天线、太阳电池阵等大部件的有限元模型都必须是未经缩聚的纯物理模型.为在无法获得大部件物理模型的情况下得到整星的星箭耦合力学分析模型,文章提出卫星星箭耦合分析模型的二次缩聚方法,可将由卫星本体物理模型和天线一次缩聚模型组成的混合模型二次缩聚为满足运载格式的星箭耦合分析出口模型,并与火箭研制方联合开展星箭耦合分析及结果校验,验证了该方法的有效性. 展开更多
关键词 卫星 星箭耦合分析 有限元模型 混合界面 模态综合法 二次缩聚
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基于模型的卫星测控信息流数字化设计方法研究与实现 预览
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作者 叶勉 韩笑冬 +1 位作者 郝燕艳 王依一 《中国空间科学技术》 CSCD 北大核心 2019年第3期71-80,共10页
测控信息流设计是卫星信息总体设计的重要组成部分,设计结果体现了卫星遥测遥控信息流向,其合理性和正确性决定了卫星资源配置以及星上仪器布局等.传统的测控信息流设计方法耗时长,效率低,操作繁杂,已经无法满足信息化研制模式以及与日... 测控信息流设计是卫星信息总体设计的重要组成部分,设计结果体现了卫星遥测遥控信息流向,其合理性和正确性决定了卫星资源配置以及星上仪器布局等.传统的测控信息流设计方法耗时长,效率低,操作繁杂,已经无法满足信息化研制模式以及与日俱增的任务需求.通过对卫星测控信息流设计过程的研究,设计了一种全新的基于模型的卫星测控信息流数字化设计方法,通过基于图形化等效建模来实现测控信息流数字化设计,不仅能够有效地弥补传统方法的不足,同时有利于优化测控信息流向设计.以某卫星为应用背景进行试用验证,设计工时减少了97.5%,设计正确率达到100%.该方法能够提高设计效率和质量,促进测控信息流设计流程、方法与产品的规范性,进一步提升信息流设计的自动化程度. 展开更多
关键词 卫星 测控信息流 信息总体设计 等效模型 数字化
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基于贪婪策略的遗传算法求解多星观测任务优化 预览
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作者 刘翔 雷明佳 +2 位作者 陈韬亦 陈金勇 冯小恩 《无线电工程》 2019年第1期57-62,共6页
针对多星观测任务优化这一复杂度高的问题,在构建观测任务模型和任务规划模型的基础上,较为全面地考虑了观测窗口时间约束、姿态调整约束、观测过渡时间约束、光照条件及能量平衡约束和存储资源约束等条件,并建立了相应的数学模型。针... 针对多星观测任务优化这一复杂度高的问题,在构建观测任务模型和任务规划模型的基础上,较为全面地考虑了观测窗口时间约束、姿态调整约束、观测过渡时间约束、光照条件及能量平衡约束和存储资源约束等条件,并建立了相应的数学模型。针对一般遗传算法在观测任务规划中应用时收敛速度慢的问题,设计了基于贪婪策略的遗传算法,采用STK生成多星观测任务列表,并在Matlab中编程求解观测任务规划方案,通过对比基于贪婪策略的遗传算法和一般遗传算法的性能,说明该方法在保证遗传算法收敛精度的前提下能提高算法的收敛速度,有效解决多星观测任务优化问题。 展开更多
关键词 卫星 观测任务优化 贪婪策略 遗传算法
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Regional and Global Land Data Assimilation Systems: Innovations,Challenges, and Prospects
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作者 Youlong XIA Zengchao HAO +5 位作者 Chunxiang SHI Yaohui LI Jesse MENG Tongren XU Xinying WU Baoqing ZHANG 《气象学报:英文版》 SCIE CSCD 2019年第2期159-189,共31页
Since the North American and Global Land Data Assimilation Systems(NLDAS and GLDAS) were established in2004, significant progress has been made in development of regional and global LDASs. National, regional, projectb... Since the North American and Global Land Data Assimilation Systems(NLDAS and GLDAS) were established in2004, significant progress has been made in development of regional and global LDASs. National, regional, projectbased, and global LDASs are widely developed across the world. This paper summarizes and overviews the development, current status, applications, challenges, and future prospects of these LDASs. We first introduce various regional and global LDASs including their development history and innovations, and then discuss the evaluation, validation, and applications(from numerical model prediction to water resources management) of these LDASs. More importantly, we document in detail some specific challenges that the LDASs are facing: quality of the in-situ observations, satellite retrievals, reanalysis data, surface meteorological forcing data, and soil and vegetation databases;land surface model physical process treatment and parameter calibration;land data assimilation difficulties;and spatial scale incompatibility problems. Finally, some prospects such as the use of land information system software, the unified global LDAS system with nesting concept and hyper-resolution, and uncertainty estimates for model structure,parameters, and forcing are discussed. 展开更多
关键词 LAND data ASSIMILATION system (LDAS) REGIONAL and GLOBAL LDASs in-situ observation satellite RETRIEVAL LAND surface model (LSM)
船载卫星遥感数据接收天线跟踪精确度改进方法 预览
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作者 陈元伟 张国梁 戎景会 《航天器工程》 CSCD 北大核心 2019年第2期85-90,共6页
针对船载卫星遥感数据接收天线的动态跟踪航行特点,提出一种提高船载卫星遥感数据接收天线跟踪精确度的方法。通过天线伺服控制设计和计算机程序,克服船姿扰动对天线跟踪的影响,实现快速捕获目标卫星并进行精确稳定跟踪,从而解决恶劣海... 针对船载卫星遥感数据接收天线的动态跟踪航行特点,提出一种提高船载卫星遥感数据接收天线跟踪精确度的方法。通过天线伺服控制设计和计算机程序,克服船姿扰动对天线跟踪的影响,实现快速捕获目标卫星并进行精确稳定跟踪,从而解决恶劣海况下,船行过程中对X频段低轨卫星全空域、无盲区跟踪和可视区域内的高精度指向跟踪问题。该方法已在雪龙号船载卫星遥感接收处理系统建设中得到应用,可为后续舰船上建设遥感卫星接收系统提供借鉴。 展开更多
关键词 卫星 前馈控制 船摇隔离 船姿扰动 精确跟踪
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Ionospheric time delay corrections based on the extended single layer model over low latitude region
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作者 Sahithi Karanam D.Venkata Ratnam J.R.K.Kumar Dabbakuti 《大地测量与地球动力学:英文版》 2019年第3期235-240,共6页
Ionospheric delay error is considered to be one of the most prominent factors impacting the Global Navigation Satellite Systems(GNSS) positioning and navigation accuracies. Due to dispersive nature and anisotropic of ... Ionospheric delay error is considered to be one of the most prominent factors impacting the Global Navigation Satellite Systems(GNSS) positioning and navigation accuracies. Due to dispersive nature and anisotropic of the ionosphere above certain regions, the positioning accuracy is seriously affected when using a precision-limited model. In this paper, an attempt has been taken to estimate ionosphere-delays based on Planar Fit(PF) and Spherical Harmonic Function(SHF) models by applying the commonly used single layer Model(SLM) and an extended single layer model(ESLM) which has been explored sparsely over the region. The results show that ESLM of PF and SHF techniques performed better in estimating ionospheric delay compared to the existing SLM model. Although the performance of the ESLM approach is almost comparable to the SLM results during the quiet ionospheric conditions, the ESLM-PF and ESLMSHF models led to respective improvements of 4.66% and 7.14% over the classically used SLM model under the disturbed ionospheric conditions. In view of the uneven variability of equatorial/low latitude ionosphere above the Indian subcontinental region, the suitability of ESLM-PF and ESLM-SHF models has been emphasized and suggested for assessing its completeness and reliableness across other parts of the globe. The output of this work may be useful for high precession GNSS positioning through mitigating the ionospheric delays under quiet as well as varied ionospheric conditions across the low/equatorial latitude regions. 展开更多
关键词 Global Navigation Satellite Systems(GNSS) Planar fit(PF) Spherical HARMONIC Function(SHF) EXTENDED SINGLE layer model(ESLM)
Prospects for Satellite Services 预览
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作者 帕科姆·雷维 《卫星应用》 2019年第2期39-43,共5页
2018年12月5—6日,由中国航天工业科学技术咨询有限公司主办的第六届航天国际化发展论坛在北京召开。欧洲咨询公司(Euroconsult)总裁帕科姆·雷维(Pacome Revillon)在论坛上作了题为Prospects for Satellite Services的报告。报告... 2018年12月5—6日,由中国航天工业科学技术咨询有限公司主办的第六届航天国际化发展论坛在北京召开。欧洲咨询公司(Euroconsult)总裁帕科姆·雷维(Pacome Revillon)在论坛上作了题为Prospects for Satellite Services的报告。报告预测卫星服务业未来走势呈现四大特征:一是航天技术与服务创新持续加速;二是机载宽带接入、自动驾驶、万物互联、万户融通等新业务模式层出不穷;三是新增私人与政府投资主体不断涌现;四是行业生态系统转型牵引未来发展。本刊将报告内容原文刊出。 展开更多
关键词 PROSPECTS for SATELLITE SERVICES
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Infrared Radiance Simulation and Application under Cloudy Sky Conditions Based on HIRTM 预览
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作者 Jian-Hua Qu Jun-Jie Yan Mao-Nong Ran 《电子科技学刊:英文版》 CAS CSCD 2019年第2期161-170,共10页
An algorithm based on hyperspectral infrared cloudy radiative transfer model (HIRTM) is introduced and a simulation method for infrared image of the generation geostationary meteorological satellite is proposed. Based... An algorithm based on hyperspectral infrared cloudy radiative transfer model (HIRTM) is introduced and a simulation method for infrared image of the generation geostationary meteorological satellite is proposed. Based on the parameters from weather research and forecast (WRF), such as the water content, atmospheric temperature, and humidity profile, the simulation data for the advanced Himawari imager (AHI) infrared radiative (IR) channels of Himawari-8 are obtained. Simulated results based on HIRTM agree well with the observed data. Further, the movement, development, and change of the cloud are well predicated. And the simulation of IR cloud image for the weather forecast has been obtained. This paper provides an improved method for evaluation and improvement of regional numerical model for weather forecast. 展开更多
关键词 HYPERSPECTRAL INFRARED CLOUDY RADIATIVE transfer MODEL (HIRTM) regional numerical MODEL satellite cloud image
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面向卫星在轨应用的目标实时探测技术及实现
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作者 夏鲁瑞 薛武 《光学与光电技术》 2019年第4期71-76,共6页
针对卫星在轨处理图像以获取高价值目标信息的需求,分析了卫星在轨探测系统技术要求,开发了由高性能处理器组成的嵌入式系统,能支持目标探测算法的高速计算。研究了通过中值滤波、阈值分割、连通域标记和角度测量实现目标实时探测的算法... 针对卫星在轨处理图像以获取高价值目标信息的需求,分析了卫星在轨探测系统技术要求,开发了由高性能处理器组成的嵌入式系统,能支持目标探测算法的高速计算。研究了通过中值滤波、阈值分割、连通域标记和角度测量实现目标实时探测的算法,使用多类样本图像对算法进行系统测试,计算时间小于1 s,能够检测出目标并计算其位置信息,满足在轨探测系统要求。 展开更多
关键词 卫星 目标探测 图像实时处理 在轨应用 嵌入式系统
中国科学院与“两弹一星”工程
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作者 刘艳琼 《中国科学院院刊》 CSSCI CSCD 北大核心 2019年第9期1003-1013,共11页
“两弹一星”的成功,是中国大国地位的奠基石。从1955年我国决定发展原子能,到1970年第一颗人造卫星发射成功,在“两弹一星”的研制过程中,中国科学院承担了与核弹、导弹相关的大量配套科技任务,负责整个卫星系统的技术抓总,完成卫星本... “两弹一星”的成功,是中国大国地位的奠基石。从1955年我国决定发展原子能,到1970年第一颗人造卫星发射成功,在“两弹一星”的研制过程中,中国科学院承担了与核弹、导弹相关的大量配套科技任务,负责整个卫星系统的技术抓总,完成卫星本体的研制,并建立地面测控系统。中国科学院为我国“两弹一星”工程作出了重大贡献。 展开更多
关键词 核弹 导弹 卫星 中国科学院 技术
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