采用PPP技术建立高精度GNSS控制网的方法  

Method of establishing high-precise GNSS control network using PPP technology

作　　者：吴磊 李博峰 王苗苗 WU Lei;LI Bofeng;WANG Miaomiao(College of Surveying and Geo information,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学测绘与地理信息学院,上海200092

出　　处：《导航定位学报》2018年第4期112-118,共7页Journal of Navigation and Positioning

基　　金：国家自然科学基金项目(41622401;41574023)

摘　　要：针对传统GNSS工程控制网建立中联测方案复杂,会消耗大量人力和财力,以及传统控制网平差软件忽略基线间相关性导致平差验后点位精度偏高的问题,提出采用PPP技术、考虑基线间随机相关性来建立高精度控制网的思路:首先计算所有网点的PPP坐标;并以此构造基线网及其方差-协方差矩阵,采用去相关策略对基线网先去相关处理再平差的思想,求得较客观的验后点位精度;最后实验比较基于基线联测和基于PPP构建控制网的平差结果。结果表明:2h的基线联测,进行控制网平差其精度能达到毫米级,且测站坐标与真值相比误差在1cm以内;2h观测计算PPP坐标,再构建基线网进行平差,测站坐标与真值相比误差在5cm以内,若要达到毫米级需求,则观测时间可延长到12h;对短时间观测的大尺度控制网平差,无论是基线联测还是PPP方式构建控制网,都应该考虑基线间随机相关性对精度评定的影响。Aiming at the problems that the complicated scheme of the joint measurement in the traditional establishment of high precise GNSS control network causes a lot of manpower and finaneial resources, and the lack of correlation between baselines in traditional adjustment software of control network leads to the higher accuracy of post adjustment points, the paper proposed the thought that the high precise control network was established by considering random correlation between baselines with PPP technology： the PPP coordinates of all the nodes were calculated, and the baseline network and its variane-covarianee matrix were constructed; then the decorrelation strategy of decorrelating-adjusting was used on the baseline network to obtain a relatively objective accuracy of post-testing points; finally the adjustment output based on baseline measurement were comtrasted with that based on PPP control network. Experimental results showed that： for 2 h baseline measurement, the accuracy of control network adjustment could reach millimeter level, and the error between the station coordinates and the true values could be within the range of 1 cm; for 2 h observation and cal culation of PPP coordinates, and the adjustment by constructing baseline network, the error between the station coordinates and the true values could be within 5 cm, while the observation time should be extended to 12 h so as to reach the millimeter-level require ments; moreover, for large scale control network adjustment of short-time observation, the influence of random correlation between base lines on the accuracy evaluation should be considered in both methods of baseline measurement and PPP constructed control network.

关 键 词：精密单点定位 全球卫星导航系统 控制网平差 基线相关性 去相关 

分 类 号：P228[天文地球—大地测量学与测量工程]