GNSS多系统自主完好性监测与信号质量评估技术研究

发布时间：2018-01-07 05:22

本文关键词：GNSS多系统自主完好性监测与信号质量评估技术研究　出处：《国防科学技术大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着卫星导航技术的飞速发展,其应用不仅在海、陆、空、天等军事领域开花结果,同时也在航空、运输、农业、建筑等诸多民用领域落地生根。随着导航精度的不断提高,人们对导航系统完好性的要求也愈加严格。本文对此展开研究,具体研究内容包含如下:第一部分针对基于识别门限的双星故障识别算法存在故障抵消识别率低的问题,利用奇偶空间矩阵任意两个列向量生成的子空间,通过判断无噪声条件下奇偶矢量与其在该故障特征空间投影的相关性来识别故障卫星。同时,通过分析双星故障矢量方向和故障偏差幅值大小,给出了双星故障条件下的用户误差保护水平计算方法。最后对双系统下基于故障特征空间的双星故障识别算法进行了仿真分析,仿真结果表明,与基于识别门限的RAIM算法相比,本文提出的算法故障识别率能够从60%提高到90%以上。第二部分针对ARAIM基本算法中完好性风险平均分配,而现有RAIM算法中针对完好性风险动态分配理论计算复杂的问题,通过给定初值减少计算迭代次数得到次优解,改善了危险误导信息概率动态分配方案。与完好性风险平均分配算法相比,改进后的算法能有效降低保护水平,提高系统可用性,同时降低了完好性风险最优配置理论算法的计算复杂度。最后对ARAIM算法在不同应用场合下的可用性进行了仿真分析,仿真结果表明,多系统组合应用能有效提高系统完好性性能,BDS+GPS双系统应用下已基本能满足中国区域LPV-200的要求。第三部分针对导航参数未知的GNSS离线信号,无法利用捕获跟踪方式估计信号参数实现对信号监测评估的背景,结合工程实践需求,利用滑动相关和数据累加的方法实现了对基于窄波束天线的导航信号参数估计。根据导航信号自相关特性,通过一小段切片数据与原始信号作相关处理估计GNSS信号码周期、载波多普勒等参数,通过信号周期累积平均提高信噪比,进一步估计信号载波相位、初始码相位等信号参数,利用仿真信号验证了该方法的有效性。最后将该方法引入GNSS在轨信号质量的监测与评估,搭建导航信号质量监测分析的软硬件平台,实现了对GNSS实测信号的分析评估。最后,对本文的研究成果和工程价值进行了总结,并指出了目前研究工作中还存在的不足以及未来待完善的部分。本文的研究内容对卫星导航系统完好性具有重要指导意义,其研究成果可直接应用于在轨卫星导航信号质量的监测与评估。
[Abstract]:With the rapid development of satellite navigation technology, its application not only in the sea, land, air, and other military field, but also in aviation, transportation, agriculture, construction and other fields. With the air plant navigation accuracy continues to improve, people on the navigation system integrity requirements more strict. In this study, specific the research contents include as follows: the first part is the fault offset the low recognition rate to solve the problem of fault detection algorithm based on the recognition threshold, using the parity space matrix of any two column vector subspace generated by judging the correlation, noise free conditions and the fault feature parity vector space projection to identify fault satellites. At the same time, through the analysis of fault detection and fault vector direction deviation amplitude, gives the user error protection level binary fault condition calculation method. At the end of Fault feature space based on binary fault identification algorithm of dual system is simulated. The simulation results show that compared with the RAIM algorithm to identify the threshold based fault identification algorithm is proposed in this paper can rate increased from 60% to more than 90%. The second part of the integrity risk the average distribution of the basic ARAIM algorithm, and the existing RAIM algorithm for integrity risk allocation theory of the computational complexity of the problem, given by the initial reduction of the number of iterations to obtain suboptimal solutions, improve the risk of misleading information dynamic probability distribution scheme. Compared with the average integrity risk allocation algorithm, the improved algorithm can effectively reduce the level of protection, improve system availability, and reduce the calculation of integrity risk the optimal allocation theory of the complexity of the algorithm. Finally the availability of the ARAIM algorithm in different application situations are simulated, the simulation results table The multi system combination can effectively improve the system integrity performance, application of BDS+GPS double system can basically meet the requirements of LPV-200 GNSS. China area for navigation offline signal with unknown parameters in third parts, can not be used to evaluate the acquisition and tracking method to estimate signal monitoring background signal parameters, combined with the engineering practice, using the method of sliding and the related data accumulated for estimation of navigation signal parameters based on narrow beam antenna. According to the navigation signal autocorrelation, estimation of GNSS channel number cycle through a short section data and original signal processing, signal parameters such as carrier Doppler, through the cumulative average cycle to improve the signal-to-noise ratio, further estimation of signal carrier phase, initial code phase signal parameters, verify the validity of the method by using the simulation signal. Finally the method of introducing GNSS on signal quality Monitoring and assessment, setting up the hardware and software platform analysis of signal quality monitoring, the evaluation and analysis of the measured GNSS signal. Finally, this paper summarizes the research results and the value of the project, and points out the deficiencies in current research and future need to be improved. The research content of this paper is an important guiding significance to the satellite navigation system integrity, monitoring and evaluation of the research results can be directly applied to the satellite navigation signal quality.

【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN967.1

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