GPS伪卫星组合定位方法及在变形监测中的应用

针对GPS在城市高楼密集区、深山峡谷等区域所跟踪的可见星数目少且分布不佳导致定位精度下降,以及GPS系统本身在垂直方向定位精度较差的问题,提出GPS伪卫星组合定位新方法,利用伪卫星增强GPS技术提高定位精度。建立了GPS和伪卫星组合定位的观测模型,分析了伪卫星多路径效应的特点,给出了减弱伪卫星多路径误差的有效方法。对某大坝坝区的实测数据进行处理的结果表明,文中所提出的方法能有效地减弱伪卫星多路径效应产生的误差,GPS和伪卫星组合定位方法提高了系统的定位精度,特别是垂直方向的精度。

Integration of GPS and Pseudolites for Deformation Monitoring

Although GPS is widely used for precision surveys,i.e.deformation monitoring,survey environments,such as in urban areas,deep open-pit mines and valleys,the limited number of visible GPS satellites,thus decreasing the survey accuracy.Integration of GPS and pseudolites(PLS) survey system can strengthen the positioning geometry.This paper concentrates on the study of its application in deformation monitoring.The methodology for integration of GPS and PSL measurements has been developed,in particular the method/strategy to estimate PSL multipath effect,one of the server sources of errors in PSL measurements.An analysis illustrates how PSL measurements can improve the strength of positioning geometry at a hydro-power dam.A set of real GPS/PSL observations is processed to demonstrate the developed methodology.