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Interpolation Fitting Algorithm in Time-Space Domain of Differential Barometric Altimetry

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Journal of Beijing Institute of Technology 2019年第1期28卷 119-128页

作者： Zhengqun Hu Lirong Zhang guanyi ma Yuanfa Ji National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Cognitive Radio and Information Processing Ministry of EducationGuilin University of Electronic Technology Guangxi Key Laboratory of Precision Navigation Technology and Application

In order to overcome the limitations of a unitary reference station in mobile communication positioning network differential barometric altimetry(DBA)and broaden the action scope of the reference station and improve positioning accuracy of elevation,an integrated interpolation algorithm model based on generalized extended approximation(GEA)algorithm and Kriging interpolation in time-space domain of reference station is *** the time domain,barometric measured data is considered the maximum value estimated by bilateral extension to avoid wrong direction of estimation,which is approaching true *** the spatial domain,barometric relevance among multiple reference stations is utilized,the weighted coefficients of multiple reference stations is calculated by the integrated algorithm model based on the GEA algorithm and Kriging *** impact of each reference station to the measured station is quantified,so that a virtual reference station is constructed,which can overcome the limitation of barometric correction by a unitary reference *** addition,the measurement error due to irregular change in atmospheric pressure will be eliminated.

关键词： differential barometric altimetry(DBA) multi reference station generalized extended approximation(GEA) Kriging algorithm

Research on positioning enhancement scheme of CAPS via UWB pseudolite

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Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 733-737页

作者： XIAO Zhu BAI Jing ma guanyi FAN JiangTao YI KeChu College oflnformation Science and Engineering Hunan UniversityChangsha 410082China State Key Laboratory oflntegrated Service Networks Xidian UniversityXi'an 710071China Key Laboratory oflntelligent Perception and Image Understanding of Ministry of Education Xidian UniversityXi'an 710071China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

The positioning precision of the transmitting Chinese Area Positioning System(CAPS) is reduced due to the non-ideal distribution of the satellite *** and navigation enhancement methods are able to improve the reliability and accuracy of the positioning system,especially for users in special regions and special *** this paper,a positioning enhanced scheme based on ultra-wide band(UWB) pseudolite is proposed for *** is demonstrated that the link budget of UWB pseudolite satisfies the FCC's emission mask *** localization algorithm of the enhanced CAPS is *** simulations indicate that the positioning precision of the proposed enhanced scheme is improved greatly,and the feasibility of the enhanced scheme is thus proved.

关键词： CAPS UWB positioning enhancement pseudolite

A neural network based ionospheric TEC derivation method with only carrier phase observations

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A neural network based ionospheric TEC derivation method wit...

A study of ionospheric height’s effects on the derivation of GPS-TEC

第十一届中国卫星导航年会

作者： Weijun Lu guanyi ma National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences

In derivation of ionospheric total electron content(TEC) with global navigation satellite system(GNSS), because the pseudorange contains large observation noise and the carrier phase includes unknown

关键词： Ionosphere Total electron content Artificial neural network Instrumental bias Root mean square error

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A study of ionospheric height’s effects on the derivation o...

A Study of TEC storm on 13 October 2016

第五届中国卫星导航学术年会

作者： Xiaolan Wang guanyi ma University of Chinese Academy of Sciences National Astronomical Observatories Chinese Academy of Sciences

Based on a thin layer assumption of the ionosphere and the spherical harmonic model, this paper adopts the algorithm spherical harmonic model to de- rive the total electron content （TEC） for a GPS observational chain with 60 dual frequency receivers in the whole world. The paper examines the performance of the algorithm and investigates the effects the assumed ionospheric height on the derived TEC by applying it to the data selected October 1, 2004. The results show that the data can be well fitted,and there are some effects to GPE-TEC but with- out dependence on the ionospheric model height.

关键词： GPS TEC ionospheric height spherical harmonic model

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A Study of TEC storm on 13 October 2016

基于双频GPS观测的电离层TEC与硬件延迟反演方法

第九届中国卫星导航学术年会

作者： Qingtao Wan Jinghua Li Xiaolan Wang Jiangtao Fan Jie Zhang guanyi ma National Astronomical Observatories Chinese Academy of Sciences

An ionospheric positive storm on 13 October 2016 was *** longitude effect of ionospheric storm along 40°N latitude region is studied with 23 GPS stations from 0°E to 360°*** electron content(TEC) was calculated with polynomial method,and TEC difference between the storm time and quiet time(ΔTEC) were *** variations of TEC difference were different at different *** was a positive phase storm at the local time day side region,while the variations were not obvious at the night side *** maximum value of ΔTEC was about 25 TECU at 330°E at about 1400 UT on 13 October *** Ionosonde data at EB040(0.5 °E,40°N) and RL052(51.5 °N,359.4 °E) were also used to study the ionospheric *** Δfo F2 of RL052 increased earlier that low latitude ionosonde of *** was a second peak of ΔTEC at the local night time about 2000 LT on 13 October *** latitude effect of ionospheric storm was also studied with 7 GPS stations at 0°E *** was found that the positive storm was obvious at high latitude region,while it was weak at low latitude *** phenomenon may be caused by the fountain *** high latitude to low latitude,ΔTEC gradually began to increase,and ΔTEC at higher latitude reached the maximum value earlier than the low *** show that the positive ionospheric storm may be caused by the equatorward surge.

关键词： GPS station Ionosonde Total electron content equatorward surge

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空间科学学报 2014年第2期34卷 168-179页

作者：王晓岚马冠一中国科学院大学北京100049 中国科学院国家天文台北京100012

利用全球定位系统(Global Positioning System,GPS)的双频观测数据反演得到电离层的总电子含量(Total Electron Content,TEC),使得广域甚至全球范围高时空分辨率的电离层观测研究成为可能,但由于GPS卫星和接收机对信号的硬件延迟可导致... 详细信息

利用全球定位系统(Global Positioning System,GPS)的双频观测数据反演得到电离层的总电子含量(Total Electron Content,TEC),使得广域甚至全球范围高时空分辨率的电离层观测研究成为可能,但由于GPS卫星和接收机对信号的硬件延迟可导致TEC测量系统偏差,因此,需要探索反演TEC并估测GPS卫星与接收机硬件延迟的有效算法.本文根据电离层电波传播理论,阐述了基于双频GPS观测提取电离层TEC的方法,给出TEC与硬件延迟的基本关系.综合研究了TEC与硬件延迟的反演方法,进行分析与归纳分类,在此基础上提出了有待深入研究的问题.

关键词： GPS 电离层 TEC 硬件延迟

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GNSS接收机锁相环最佳环路带宽的选取

电讯技术 2015年第8期55卷 890-894页

作者：张杰马冠一中国科学院国家天文台北京100012 中国科学院大学北京100049

锁相环环路带宽值的选取对于锁相环的跟踪误差性能有重要影响。基于全球卫星导航系统(GNSS)接收机中常用锁相环结构与数学模型,首先介绍了锁相环及其重要组成部分环路滤波器的结构和原理,然后分析了环路带宽的取值对锁相环两个最重要的... 详细信息

锁相环环路带宽值的选取对于锁相环的跟踪误差性能有重要影响。基于全球卫星导航系统(GNSS)接收机中常用锁相环结构与数学模型,首先介绍了锁相环及其重要组成部分环路滤波器的结构和原理,然后分析了环路带宽的取值对锁相环两个最重要的误差源——环路热噪声误差和晶振阿伦偏差的影响,给出了低动态下使锁相环总的跟踪误差最小的最佳环路带宽的理论表达式。对基于由现场可编程门阵列(FPGA)芯片、温补晶振和模/数接口电路构建的实际硬件接收机平台进行了验证,结果表明:当根据最佳环路带宽的理论表达式取环路带宽值时,锁相环的跟踪误差最小。所推得的理论表达式不仅可以应用于GNSS接收机,也适用于一般的载波跟踪环设计。

关键词： GNSS接收机锁相环环路滤波器最优环路带宽

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电离层不规则结构对GPS性能的影响

空间科学学报 2013年第2期33卷 158-169页

作者：李婧华马冠一中国科学院国家天文台北京100012 中国科学院大学北京100049

电离层不规则结构的存在可引起无线电信号的幅度和相位发生随机起伏,这种电离层闪烁现象会影响全球定位系统(Global Positioning System,GPS)的性能,降低定位精度,严重时导致信号失锁.电离层不规则结构对GPS性能的影响涉及电离层物理、... 详细信息

电离层不规则结构的存在可引起无线电信号的幅度和相位发生随机起伏,这种电离层闪烁现象会影响全球定位系统(Global Positioning System,GPS)的性能,降低定位精度,严重时导致信号失锁.电离层不规则结构对GPS性能的影响涉及电离层物理、接收机设计和表征卫星几何分布的精度衰减因子(Dilution of Positioning,DOP)等多方面因素.本文通过对表征电离层不规则结构参数的分析,根据GPS接收机跟踪环路和闪烁信号模型,综合研究了电离层闪烁对GPS接收机载波跟踪环和码跟踪环跟踪误差的影响;结合实际观测,评述了电离层不规则结构对单频和双频GPS接收机定位性能的影响,在此基础上提出了有待深入研究的问题及具体建议.

关键词：电离层不规则结构电离层闪烁 GPS 跟踪环路失锁定位误差

最大值约束的广义延拓逼近GNSS码鉴相算法

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系统工程与电子技术 2017年第4期39卷 714-720页

作者：张杰马冠一李婧华王晓岚中国科学院大学北京100049 中国科学院国家天文台北京100012

针对GNSS码跟踪环高精度鉴相需求,提出了一种最大值约束的广义延拓逼近码鉴相算法,利用5个相关臂的相关结果建立广义延拓逼近模型,拟合得到相关值分布函数,进而得到码相位差。同时利用相关结果最大的相关节点对拟合的相关值分布函数进... 详细信息

针对GNSS码跟踪环高精度鉴相需求,提出了一种最大值约束的广义延拓逼近码鉴相算法,利用5个相关臂的相关结果建立广义延拓逼近模型,拟合得到相关值分布函数,进而得到码相位差。同时利用相关结果最大的相关节点对拟合的相关值分布函数进行约束,进一步提高了码相位差的估计精度和适应性。将新算法与常用的归一化超前减滞后包络鉴相算法从鉴相线性范围、牵引范围和鉴相误差三方面进行了对比。蒙特卡罗仿真和在GPS软件接收机上对实际GPS信号采样数据进行测试的结果表明,结合最大值约束的广义延拓逼近鉴相误差性能大大优于传统的归一化超前减滞后包络鉴相,可以有效地提升码鉴相器的鉴相精度。

关键词：码鉴相器延迟锁定环广义延拓逼近最大值约束