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第三届中国卫星导航学术年会

作者： Jian Jun Yin 1, 2., Si Hao Zhao 3 , Jian Qiu Zhang 2.1 State Key laboratory of ASIC & System, Fudan University, 2.Electronic Engineering Department, Fudan University 3 china Acadamy of {2. technology

In this paper, a novel filtering method, i.e., the expanded central difference filter, was established for global navigation satellite systems （GNSS） navigation. The approach involved modelling an expanded state {2. model by adopting the polynomial predictive idea and state dimension expansion. The new model was established without the exact knowledge of the original state dynamics, i.e., no matter we knew the original state propagation well or not, which was common in practice. A correspondent expanded state {2. central difference filter （ECDF） was then presented based on the proposed model. The simulation results of the GPS navigation demonstrated that the proposed method did work better than the existed central difference filter （CDF）, especially when the state dynamics were not known well.

关键词： GNSS state space model central difference filter expanded central difference filter

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System time offset based RAIM in combined GPS/Beidou navigation system

System time offset based RAIM in combined GPS/Beidou navigat...

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第三届中国卫星导航学术年会

作者： XU LongXia1,2.3*1, LI XiaoHui1,2. XUE YanRong1,2.3, CAI ChengLin4& GUO MeiJun1,3 1National Time Service Center, Chinese Academy of Sciences, Xi’an 710600, china 2.ey laboratory of Precision {2. and Timing technology, Chinese Academy of Sciences, Xi’an 710600, china 3Graduate University of Chinese Academy of Sciences, Beijing 100039, china 4Guilin University of Electronic technology, Guilin, 541004, china

Compatibility and interoperability of GNSS （Global navigation Satellite System） are becoming the main trend of future navigation. However, each navigation system has a time scale. When users positioning with not only one system, the time offset between them must be considered. There are several ways to acquire system time offsets. By adding unknown variables in the combined position equation to solve this variable is the commonly used way. For positioning with multi-constellations, system time offsets are some kind of burden which must be taken into account. This paper takes full use of the obtained offsets and proposes a new fault detection method for RAIM （Receiver Autonomous Integrity Monitoring）. Simulations are made to estimate the ability of this new method. This new method takes the high stability of system time offsets of GPS/Beidou system and applies it to assistant fault detection. This method has no additional requirements for navigation system and is fit for applied in receivers. It can be expected this method will be one means of RAIM for Beidou navigation system when integrated with other GNSS in future.

关键词： Compatibility and Interoperability Time Offset Receiver Autonomous Integrity Monitoring Fault Detection.

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Research on AutoNav-Guiding technology for Airplane Taxiing

Research on AutoNav-Guiding Technology for Airplane Taxiing

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第三届中国卫星导航学术年会

作者： Wu Hai-tao1 2.Zou De-cai1 2.Han Tao1 2.Lu Xiao-chun1 2.1.National Time Service Center Chinese Academy of Sciences Xi’an 710600 china 2.Key laboratory of Precision {2. and Timing technology Chinese Academy of Sciences Xi’an 710600 china

Aircraft taxiing on the ground can reach or leave from parking bay with the help of"FOLLOW ME"airport guide car,a process that requires a lot of manpower,material and financial *** the extensive use of Satellite-based navigation system and the rapid development of modern communication technology and automatic control technology,this paper presents and studies aircraft automatic guidance technology to replace the airport guide car during airplane *** basic idea is that,based on the landing PVT information provided by GNSS navigation equipment onboard the aircraft,control tower planes aircraft taxiing routes after landing automatically according to airport GIS data and the actual airport flight schedule,and sends to the aircraft crew through wireless communication *** crew will match the real-time aircraft GNSS positioning information to the taxiing route provided by control tower using finite element theory coordinates matching *** matching results will be shown on the cockpit Multi-Function Display（MFD）or on the Head-up Display of windshield glass with the flashing arrows to guide the pilot taxiing under the established ***-guiding technology occupies a certain advantage in the implementation complexity,cost,size and energy consumption compared to aircraft taxiing with the help of airport guide car,and auto-guiding technology can also be used for the machine automatic guidance in the other places.

关键词： AutoNav-Guiding taxiing route finite element coordinates matching

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Study on the Coordinate Reference Frame of the Indoor/outdoor Seamless positioning System

Study on the Coordinate Reference Frame of the Indoor/outdoo...

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第三届中国卫星导航学术年会

作者： Cheng Liu 1, 2. , Huli Shi 1, 2., Ziping Lv 3 , Zhongliang Deng 4 1. National Astronomical Observatories, Chinese Academy of Science, Beijing 100012. china 2. Graduate University of Chinese Academy of Science, Beijing 100190, china 3. china Telecom Satellite Communications Limited, Beijing 100083, china 4. Beijing University of Posts and Telecommunications, Beijing 100876, china

The LBS and indoor positioning technologies are being developed rapidly in nowadays, and the integrated positioning and {2. system of indoor/outdoor is gradually becoming a reality. However, to describe the spatial points, a specific coordinate reference frame is needed as the space basis and premise, which is appeared to be lacking of research for a long time. This paper studied and discussed a coordinate reference frame and its implementation method based on the research project of outdoor/indoor seamless positioning system. The coordinate frame could integrate a variety of outdoor and indoor positioning techniques and methods, and provide a spatial basis for seamless positioning. It also provides a reference for the true realization of the coordinate reference frame in the future.

关键词： LBS Indoor positioning Coordinate system Coordinate reference frame

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Accurate Quantification of Grassland Cover Density in an Alpine Meadow Soil Based on Remote Sensing and GPS

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Pedosphere 2005年第6期15卷 778-783页

作者： LIU Yan-Sui HU Ye-Cui PENG Liu-Ying Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） Graduate School of Chinese Academy of Sciences Beijing 100039 （China）

The principles of remotely estimating grassland cover density in an alpine meadow soil from space lie in the synchronous collection of in situ samples with the satellite pass and statistically linking these cover densities to their image properties according to their geographic coordinates. The principles and procedures for quantifying grassland cover density from satellite image data were presented with an example from Qinghai Lake, china demonstrating how quantification could be made more accurate through the integrated use of remote sensing and global {2. systems (GPS). An empirical model was applied to an entire satellite image to convert pixel values into ground cover density. Satellite data based on 68 field samples was used to produce a map of ten cover densities. After calibration a strong linear regression relationship (r2.= 0.745) between pixel values on the satellite image and in situ measured grassland cover density was established with an 89% accuracy level. However, to minimize positional uncertainty of field samples, integrated use of hyperspatial satellite data and GPS could be utilized. This integration could reduce disparity in ground and space sampling intervals, and improve future quantification accuracy even more.

关键词： alpine meadow soil grassland cover density quantitative remote sensing Qinghai Lake

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维普期刊数据库

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用于GNSS基带信号分析的相干累加算法

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数据采集与处理 2009年第B10期24卷 124-127页

作者：贺成艳卢晓春中国科学院国家授时中心西安710600 中国科学院精密导航定位与定时重点实验室西安710600 中国科学院研究生院北京100190

在对一般累加平均算法的原理、应用条件和误差来源等进行分析的基础上,提出了一种可以适用于更高数据速率(如500 bps)的相干累加算法,并且不需要进行导航信息的剥离。通过实验分析表明,在经过一定周期累加以后,就可以在时域观测到清晰... 详细信息

在对一般累加平均算法的原理、应用条件和误差来源等进行分析的基础上,提出了一种可以适用于更高数据速率(如500 bps)的相干累加算法,并且不需要进行导航信息的剥离。通过实验分析表明,在经过一定周期累加以后,就可以在时域观测到清晰的扩频码波形,也证明了新的累加平均算法确实可以达到提高信噪比的目的,而且比一般方法要好。

关键词：相干累加基带信号 GNSS 信噪比

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Simultaneous Localization and Map Building Using Constrained State Estimate Algorithm

Simultaneous Localization and Map Building Using Constrained...

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第二十七届中国控制会议

作者： Cao Menglong1,2.Yu Lei1,Cui Pingyuan2.1.Institute of Autonomous navigation and Intelligent Control,Qingdao University of Science & technology,Qingdao 2.6042.P.R.{2. 2.Deep space Exploration Research Center,Harbin Institute of technology,Harbin 150001,P.R.{2.

Intelligent vehicles and autonomous robots are viable in complex environments,the reliable and robust localization function of which is *** to the large variability and uncertainty of complex environments,it is difficult to rely on a specific method or a set of sensor data to correctly and robustly estimate the robot *** key to solving the localization problem is to optimally use and fuse all useful sources of information available to the mobile *** is common to have approximate digital maps of the road network.A framework for simultaneous localization and map building（SLAM） problems using road constrained Kalman filter algorithms is developed,with the emphasis on vehicle applications in large *** presents the problems of outdoor navigation in areas with combination of features and onroad *** aided SLAM algorithms,which incorporate absolute information in a consistent manner,are *** filters are commonly used to estimate the states of a mobile ***,in the application of Kalman filters,the known model or signal information often are either ignored or dealt with *** instance,constraints on state values which may be based on physical considerations are often neglected because they do not fit easily into the structure of the Kalman *** paper develops a rigorous analytic method of incorporating state equality constraints in the Kalman *** constraints may be time-varying,but it significantly improves the prediction accuracy of the *** SLAM implementation uses the road constrained kalman filter algorithm to maintain the error of vehi-cle’s location and ***,the use of this algorithm is demonstrated on a simple vehicle tracking problem.

关键词： SLAM Outdoors navigation Guidance Mobile vehicles State Constraints Estimation

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The Applications of Satellite navigation technology in Complex Scenic Environment

The Applications of Satellite Navigation Technology in Compl...

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第三届中国卫星导航学术年会

作者： Li Jun 1,Wei Haitao 2.1.The 54th Research Institute of CECT,Shijiazhuang,china 2.Satellite navigation {2. and Equipment Engineering {2. Research Center of Hebei province,Shijiazhuang,china

Satellite navigation technology has been widely used in various industries except in complex mountain scenic *** of special topography of canyons and dense forests,a navigation receiver could not function well in such *** example,the satellite searching process was often long;available satellites were hardly enough;positioning continuity could seldom be *** this article,we proposed using pseudolite to enhance navigation signals and to improve the navigation coverage in such *** the understanding of characteristics of Beidou navigation System,we came up with a system solution for the management and applications in such scenic areas.

关键词： Satellite navigation Location Based Service Smart ScenicArea Pseudo-Satellite

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Application of GNSS in School Bus Safety Monitoring

Application of GNSS in School Bus Safety Monitoring

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第三届中国卫星导航学术年会

作者： HAN Tao1 2.LU Xiaochun1 2.ZOU Decai1 2.1.National Time Service Center Xi’an 710600 P.R.china 2.Key laboratory of Precision {2. and Timing technology Chinese Academy of Sciences Xi’an 710600 P.R.china

With the "Regulations of the School Bus Safety（draft）" issued by the State Council at the end of 2.11,the management of school bus safety transportation has become a hot *** article puts forward a method of using Global navigation Satellite System（GNSS）to monitor the school bus *** school bus transport and management system,which is real-time,accurate and efficient,will be built up by integrate satellite positioning {2.,information {2.,data transmission {2.,electronic sensor {2.,information processing {2. and emergency services ***,the difference between the school bus monitoring and general vehicle monitoring is pointed ***,we find out the main reason is overload of passengers which cause the phenomenon of frequent school bus accident in ***,a School Bus Overloading Monitoring System（School-Bus-OMS）is designed to prevent the phenomenon of overload of *** that,the school bus safety monitoring system which based on GNSS and School-Bus-OMS is ***,a detailed description on the structure,function and rescuing measures of this system are given,and the corresponding mathematical models are established.

关键词： School Bus Safety GNSS Pressure Monitoring Mathematical Modeling

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Plasma Spray Forming

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厦门大学学报（自然科学版） 2002年第S1期41卷 33-34页

作者： FANG Jian-cheng 1, XU Wen-ji 2. SHI Yu-ying 1 (1.College of Mechanical Engineering and Automation, HQU, Quanzhou 362.11, china 2.School of Mechanical Engineering, DUT, Dalian 11602., china)

In the course of plasma spray, the plasma jet is comprehensively functioned by such effects as thermal pinch, magnetic pinch and mechanical compression and the flow is jetting at a high speed, the energy is concentrated and its center temperature is so high as to reach upwards of 15 000 ℃ which is capable of melting various kinds of materials inclusive of ceramic, it has a broad applied prospects in the fields of automobile, electronics, telecommunications, medical treatment, air navigation & space navigation and light industries etc because of being able to rapid fabricate thin-walled metals, ceramics and alloy parts thereof, metal moulds, functionally gradient material moulds and so on, and it has become a research spotlight for the scholars. The technology of plasma spray forming (PSF) is introduced, and the two different kinds of technique presented in this paper are studied. Some typical links in the course of technical process is also analyzed, including original prototype fabrication and surface treatment, post-treatment of formed workpiece and demoulding methods. When spraying, it should select the appropriate making methods of prototype according to the dimensions, shapes and forming accuracy as required by the formed parts. At the same time, it should be paid to the characteristic of the material for the prototype. The main purpose of surface treatment of the prototype is to raise the quality of formed parts and ensure the integrity demoulding of the coating. The method of the prototype’s surface treatment is closely related to the demoulding method, which is mainly comprised of destructive demoulding, non-destructive demoulding and composite demoulding, and is key technology in PSF. In order to eliminate these intrinsic defects and improve its performance, the fabricated parts can be given the necessary post-treatment so as to further raise the mechanical strength and surface quality. There are many methods for the post-treatment such as chemical reinforc

关键词： plasma spray forming forming technique

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