检索结果-南通市图书馆

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于GPS定位的导航地图的转换与纠正方法

同济大学学报（自然科学版） 2003年第1期31卷 69-72页

作者：胡丛玮陈武赵志弘李志林同济大学测量与国土信息工程系上海200092 香港理工大学土地测量与地理资讯学系耀天科技拓展有限公司

介绍了利用GPS定位技术对低精度的地图进行转换和变形纠正的算法 ,结合实例分析了GPS数据采集、坐标转换和利用拟合算法进行地图纠正的步骤 ,对一次多项式、二次多项式和三次多项式的拟合结果进行了比较 ,结果表明采用二次或三次多项式... 详细信息

介绍了利用GPS定位技术对低精度的地图进行转换和变形纠正的算法 ,结合实例分析了GPS数据采集、坐标转换和利用拟合算法进行地图纠正的步骤 ,对一次多项式、二次多项式和三次多项式的拟合结果进行了比较 ,结果表明采用二次或三次多项式拟合精度最好 ,获得了与GPS定位结果相匹配的精度 ,坐标分量X和Y的拟合精度分别为 8m和 17m ,纠正后的地图适合于一般车载导航和监控 .

关键词： GPS 导航地图纠正方法卫星定位系统车辆导航数字地图地图纠正多项式拟合

在线全文

学校读者我要写书评

暂无评论

闽江口河网二维潮流数学模型

台湾海峡 2002年第4期21卷 389-399页

作者：王船海梁金焰林金裕李光炽叶燕贻河海大学水资源及环境学院江苏南京210098 福建省航道局福建福州350002

应用“河网正交贴体坐标”技术拟合闽江河口多汊道河网 ,将网格控制在河道有效区域内 ,使网格空间步长大大缩小 ,提高了计算的可信度 .应用“矩阵追赶法”和“非线性二维潮流模型”等求解方法 ,很好地模拟了闽江河口复杂的潮流场 ,计算... 详细信息

应用“河网正交贴体坐标”技术拟合闽江河口多汊道河网 ,将网格控制在河道有效区域内 ,使网格空间步长大大缩小 ,提高了计算的可信度 .应用“矩阵追赶法”和“非线性二维潮流模型”等求解方法 ,很好地模拟了闽江河口复杂的潮流场 ,计算时间步长可长达 1 0min .该数学模型已在闽江口等多个工程中得到应用 ,效果良好 .

关键词：数学模型河网正交贴体坐标矩阵追赶法非线性二维潮流模型闽江口

在线全文

学校读者我要写书评

暂无评论

GPS失效性研究

现代防御技术 2006年第3期34卷 44-47,56页

作者：刘震鑫于小红装备指挥技术学院

主要从影响GPS卫星空间分布角度出发,研究在特定区域和一定时间条件下GPS卫星的失效性问题。首先分析了GPS卫星对特定区域的覆盖情况,然后针对不同位置的GPS卫星失效,考察对GPS导航精度即目标区域GDOP值的影响,并通过仿真予以验证。研... 详细信息

主要从影响GPS卫星空间分布角度出发,研究在特定区域和一定时间条件下GPS卫星的失效性问题。首先分析了GPS卫星对特定区域的覆盖情况,然后针对不同位置的GPS卫星失效,考察对GPS导航精度即目标区域GDOP值的影响,并通过仿真予以验证。研究表明对覆盖区域提供导航服务的GPS卫星中升交点赤经相差180°的两组GPS卫星对导航精度影响最为明显。

关键词： GPS 失效性仿真卫星空间

Inter-satellite Traffic Data Modeling for GNSS

在线全文

学校读者我要写书评

暂无评论

Inter-satellite Traffic Data Modeling for GNSS

The Fundamental Definitions in Radar Measurement Principle and Theory of space and Time

第三届中国卫星导航学术年会

作者： Feihong Dong 1* Jing Lv 1 Yong Yu 1 Qingqing Wang 2.Caiwu Wang 1 1 Institute of Communication Engineering PLA University of Science and technology Nanjing 2.0007 china 2.School of Earth Sciences and Engineering Hohai University Nanjing 2.0098 china

The high precision positioning and Auto navigation （AutoNav） ability achievement of next generation Global navigation Satellite System （GNSS） largely depend on the navigation satellite constellation network buildup via Inter-Satellite Links （ISLs）. The ephemeris data, TT＆C data, integrity monitoring data, AutoNav data etc. （hereafter called traffic data） transmitting in constellation network is one of the important researches. According to the characteristic of GNSS traffic data, building a suitable Inter-Satellite Traffic Data Model （ISTDM） is precondition to design ISLs communication protocols and increase the efficiency of traffic data transmission. The paper analyzes the traffic data requirement in GNSS ISLs, points out the distribution character of traffic data and abstracts out three basic classes. A general hybrid ISTDM is given. To highlight the ISTDM feature, comparisons of traffic data volume change rule are made with that of Ground Communication Network （GCN） and Satellite Communication System （SCS）. The main points are proposed when to design ISLs communication protocols. The ISTDM presented in this paper could be a reference model for GNSS construction.

关键词： GNSS constellation network traffic data model distribution character

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 1992年第3期3卷 11-22页

作者： Lin JinFirst Academy, Ministry of Aero -space Industry, P.R china P.O.Box 142.30-409, Beijing 100854,china First Academy Ministry of Aero-Space Industry P.R China P.O. Box 142-30-409 Beijing 100854 China

Fundamental definitions of distance and velocity in radar measurement principle are examined and revised from strict theoretical point of view. Synchronization scheme - for clocks in uniform, translatory relative motion is introduced as theoretical foundation for GPS and GLONASS type navigation and positioning {2.. Traditional definitions of two-way radar measurement, based on arithmetic mean vlaue concept, turn out to be special cases of revised definitions for one-way radar measurement, based on geometric mean concept, derived from synchronization of moving clocks in accordance with the principle of relativity. The essential physical meaning of Lorentz transformation is interpreted in terms of radar measured parameters. Invariance or absoluteness of four dimensional interval turns out to be invariance or absoluteness of geometric mean time interval. The Lorentz factor turns out to be ratio of geometric mean and arithmetic mean time intervals in terms of radar measured parameters. Theoretical results are illustrated transparently by numerical examples. A crucial experiment for direct testing of the second postulate of special relativity by means of GPS of GLONASS type {2. is proposed in this paper.

关键词： Radar measurement Theory of space and time Special relativity GPS GLONASS.

一种GNSS/INS/LiDAR组合导航传感器安置关系快速标定方法

在线全文

学校读者我要写书评

暂无评论

中国惯性技术学报 2018年第4期26卷 458-463,477页

作者：周阳林李广云王力李帅鑫龚培雯信息工程大学郑州450052 精密工程与工业测量国家测绘地理信息局重点实验室武汉430072 中科院光电研究院北京100094

卫星导航/惯性导航/激光扫描传感器(GNSS/INS/Li DAR)组合导航定位方法是室内外无缝导航定位的研究热点。而传感器之间高精度安置关系的确立是传感器位姿信息融合的基础,也是制约高精度组合导航定位的重要因素。针对该问题,采用三维激... 详细信息

卫星导航/惯性导航/激光扫描传感器(GNSS/INS/Li DAR)组合导航定位方法是室内外无缝导航定位的研究热点。而传感器之间高精度安置关系的确立是传感器位姿信息融合的基础,也是制约高精度组合导航定位的重要因素。针对该问题,采用三维激光扫描测量技术和多台经纬仪交汇测量的方法,设计组合导航定位系统室内高精度快速标定方案,建立传感器安置参数解算数学模型,完成了GNSS杆臂值和激光扫描传感器安置参数的标定。使用微分方程分析、蒙特卡罗法对标定结果进行精度分析,仿真实验与实际测试结果表明,传感器安置参数精度对高精度组合导航定位的影响不可忽略,采用所提出的联合测量方法,可以快速获取毫米级精度的传感器位置安置参数和角分级的传感器姿态安置参数,满足组合导航定位系统传感器安置关系标定的精度需求。

关键词：多源融合导航安置关系标定模型误差模型 GNSS杆臂值扫描传感器安置参数

Analysis of the Sun Transit Outage Impact on the Inter-satellite Link of the navigation Satellite

在线全文

学校读者我要写书评

暂无评论

Analysis of the Sun Transit Outage Impact on the Inter-satel...

The Analysis of Night-time VTEC Average Value

第三届中国卫星导航学术年会

作者： Guo Ying Li Meihong He Shanbao Pan Xin Liu Tao china Academy of space {2. Beijing P R china

For the global navigation satellite, when the two satellites which constitute an inter-satellite link are approximately in a line with the sun, generally the communication between them will be impacted by the sun transit outage. Based on the character of the native navigation satellite, this paper researched the sun transit outage impact theory, analyzed and emulated the factors which impacted the antenna noise, accomplished the link calculation. By establishing inter-satellite network topology emulate model, forecast the precise happen time of the sun transit outage. It also suggested some feasible methods to avoid the sun transit outage impact to offer reference to constitute the navigation satellite inter-satellite link project.

关键词： sun transit outage inter-satellite link noise temperature orbit analysis

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

The Analysis of Night-time VTEC Average Value

第三届中国卫星导航学术年会

作者： ZHOU Weili 1,2.SONG Shuli 2.ZHENG Zuoya 1 ZHU Wenyao 2.(1 Geomatics College, Shandong University of Science and technology, Qingdao 2.6590) (2.Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 2.0030)

Ionospheric delay is an important error source in satellite navigation and positioning, which can be weakened by Klobuchar, a widely used and practical model. The night-time VTEC (Vertical Total Electron Content) is an important characteristic parameter of Klobuchar model, the changes of night-time VTEC affect in calculation precision of the Klobuchar model directly. In this paper, with the global ionosphere VTEC (1998-2.10) produced by IGS, The rationality and reliability of night-time VTEC average value sets are estimated. The suitable time of night-time VTEC observations are analyzed according to different accuracy needs. The night-time VTEC average values are analyzed quantitatively and studied, in detail, in terms of the alteration of latitude、seasons and solar activity. The results show that night-time VTEC suitable time is 2.:00LT-06:00LT, while VTEC changes at night is greater before midnight, more stable after midnight. The night-time VTEC value has obvious seasonal variation, peak values appearing in spring and autumn, minimum value in summer. In peak years of solar activity, the average of night-time VTEC gets up to 2.-30TECU in spring and autumn, 2.TECU in winter, 15TECU in summer, having a great value in Klobuchar deviation. The changes of night-time VTEC average value with latitude is very apparent in the peak period, having the mean value from 30TECU in low latitude region down to 15 TECU in high latitude region, which is very small in valley years of solar activity, the difference with 1-2.ECU. In southern hemisphere winter, the night-time VTEC average value shows regional variation. There is a high value in India Ocean south, low value in southern pacific. The difference in those two regions is more than 15TECU in peak years, and up to 10TECU in valley years.

关键词： The Average of Night-time VTEC VTEC Solar Activity Feasibility Time of Beginning and Ending

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

基于改进粒子群优化的水下地形辅助导航方法

中国惯性技术学报 2017年第6期25卷 770-775页

作者：程向红周月华微惯性仪表与先进导航技术教育部重点实验室南京210096 东南大学仪器科学与工程学院南京210096

为了提高传统地形匹配算法的定位精度,提出一种基于改进粒子群优化的水下地形辅助导航定位算法。该算法以SINS的指示位置为中心构造搜索区域,对二维粒子群进行初始化,利用实时水深测量序列与待匹配序列之间的平均Hausdorff距离作为适应... 详细信息

为了提高传统地形匹配算法的定位精度,提出一种基于改进粒子群优化的水下地形辅助导航定位算法。该算法以SINS的指示位置为中心构造搜索区域,对二维粒子群进行初始化,利用实时水深测量序列与待匹配序列之间的平均Hausdorff距离作为适应度函数,在线性递减权重的基础上引入收敛因子对粒子的速度和位置进行约束更新,改善粒子"早熟"问题。在某海图内进行了水下地形匹配仿真实验,结果表明:初始位置误差大小不影响改进PSO算法的定位精度和匹配速度;当水下航行器初始位置误差较大时,与TERCOM算法相比,改进PSO算法的匹配精度提高了近5倍,匹配耗时缩减了近10倍。

关键词：地形辅助导航地形匹配改进粒子群优化 TERCOM匹配平均Hausdorff距离