【作者】 王尔申；

【导师】 张淑芳；

【作者基本信息】 大连海事大学 ， 通信与信息系统， 2009， 博士

【摘要】 目前,GPS已被应用于军事、航海、航空、测量、交通、勘测等几乎一切与位置、速度、时间有关的人类活动中。自从GPS系统建立以来,世界上对于GPS及其应用技术的研究越来越普及,我国在该领域的一些关键技术的研究也取得了一定的成果。本文针对国内外GPS接收机及其应用的研究现状与热点,对几个重要的关键技术进行了深入研究,包括不完整星座的定位算法、接收机定位的完好性算法、接收机应用的电磁兼容设计、嵌入式GPS接收机的设计技术等等,并在以上各个关键技术的研究中,给出了比较新颖和实用的算法和设计,取得了具有参考价值的研究成果。本文的主要研究工作包括以下几个方面的内容:1.针对GPS系统不完整星座条件下,GPS接收机无法定位的情况,研究了利用高度估计算法辅助接收机定位的方法,并在此基础上提出了高度辅助定位的改进算法。该算法通过对高度的加权估计增加定位方程组中的已知信息,进而将方程组扩充为可求解的状态。同时,提出接收机时钟偏差模型辅助接收机定位方法,这一方法基于健康钟差解算值建立时钟偏差模型,将用模型预测的钟差引入GPS观测方程中,可以辅助GPS接收机进行短时定位。实验结果表明,这两种辅助方法短时间内可以使GPS接收机继续给出定位信息,从而提高了GPS接收机导航定位的可用性。2.对卫星故障检测与隔离的RAIM算法研究进展进行了深入的分析。并针对当前广泛研究的RAIM算法中的问题,提出了基于MCMC粒子滤波的接收机自主完好性监测算法,实验结果表明,该算法可有效地检测与隔离故障卫星,解决了非高斯测量噪声环境下检测性能下降的问题。3.针对我国内河水上交通安全监管系统的现状以及现代各种船载电气、电子设备日益突出的电磁兼容问题。设计了用于船舶安全监控的船载终端系统,并分析了系统中造成电磁干扰的因素和电磁干扰的传递方式,针对终端现场实际工作遇到的具体问题提出了船载终端系统设计的EMC优化措施,通过了专业电磁兼容检测机构的测试。实验结果表明,船载终端系统长期工作稳定、可靠。4.针对自主设计的船载终端系统的需要,设计了一种基于NemeriX公司GPS芯片组的GPS接收机。实验结果表明,系统的整体设计合理,定位性能和指标完全可以满足SPS用户的需要。从中获得的数字中频GPS信号可为后续GPS信号处理的研究提供前提和基础。同时,研究了嵌入式GPS接收机配置方案和优化方法,并成功地应用到导航研究所研究的基于FPGA的GNSS接收机设计中。更多还原

【Abstract】 At present,GPS has been applied in a lot of fields including military affairs, navigation,aviation,survey,traffic,and reconnaissance,which involve all human activities associated with position,velocity,and time.Since the very beginning of the establishment of GPS system,the research on techniques of GPS receiver and its applications is becoming increasingly popular in the world,and some achievements of the key techniques in this field have been made in China.Based on current trends and hot topics of GPS receiver and its applications,this paper focuses on key techniques which include incomplete constellation positioning algorithm,receiver autonomous integrity monitoring,electromagnetic compatibility design for receiver application, embedded GPS receiver implementation technology,and so on.Moreover,several novel algorithm and practical design are proposed.And some valuable results are obtained.The main contributions of this thesis can be summarized as follows:1.Aiming at the poor positioning feature under GPS incomplete constellation environment,the altitude estimating algorithm is investigated,and its modification which aids the receiver to positioning is put forward.With the weighted altitude added into the navigation equations,they can be solved properly.Meanwhile,the clock bias forecast model is proposed.With the help of health-clock- bias calculated value,the estimated clock bias can be applied in the GPS equations to assist the GPS receiver to keep positioning within short time.The validation and analysis based on the real GPS data shows that the two kinds of methods can both enhance the availability of GPS positioning.2.The receiver autonomous integrity monitoring(RAIM) algorithm for satellite fault detection and isolation is deeply analyzed.In order to overcome the shortcomings of current RAIM algorithm,a new approach for RAIM,based Markov Chain Monte Carlo method and standard particle filtering,is presented.It can effectively detect and isolate the GPS fault satellite.Moreover,it can address the degradation of detection performance under non-Gaussian measurement noise.3.In allusion to the actuality of water safety monitoring system in our country and the contemporary problem in electromagnetic compatibility of various kinds of electronic or electrical equipments within the watercrafts,the shipborne terminal system is designed,moreover,both the factors causing electromagnetic interference and the transfer mode of the interference are investigated.Aiming at the problems occurred on the spot,some methods for EMC optimization are puts up.The shipborne terminal system has passed the testing of EMC measurement institution.The running results and experiments data show that the Electromagnetic Compatibility techniques used in the design of shipborne terminal system well ensure the system’s long-term stable and reliable running.4.In order to fulfill the needs of shipborne terminal system,a method to design GPS receiver which based on one chipset produced by NemeriX company is given out. The experiments show that the whole design of the system is reasonable,and the performance indexes fulfill SPS users’ demand perfectly.At the same time,GPS digital intermediate frequency signal may be extracted from the receiver,and it is both premise and base for further research of GPS signal processing.In addition,the configuration scheme and optimize plan for embedded GPS receiver are investigated,and successfully applied in the implementation of GNSS receiver based on FPGA.更多还原