基于观测值域的多路径消除方法及其在GNSS实时变形监测中的应用

The Multipath Mitigation Method Based on Observation Domain and Its Application in GNSS Real-Time Deformation Monitoring

首先研究多类卫星的轨道回归周期特性并推导相应公式,然后讨论基于观测值域的多路径消除算法,最后利用实测数据验证该算法的可行性。结果表明,采用观测值域多路径误差修正的方法,使GPS、BDS和GPS+BDS平均定位精度在北、东和高程方向分别提高42%、38%和54%。

Carrier multipath error is the main source of error for the short-range mm-level real-time relative positioning of GNSS.Sidereal filtering based on satellite orbit repetition is an effective method of multipath mitigation.The large revisiting orbital period differences among multi-class GNSS satellites lead to the limitation of multipath mitigation based on the coordinate domain sidereal filtering.In order to solve this problem,the revisiting orbital period characteristics of different types of satellites are firstly investigated and the formula for all types of satellites are also deduced.Then the multipath mitigation algorithm based on the observation domain is discussed in details.Finally,the feasibility of this algorithm is verified by the measured real dataset.Our results show that,by the sidereal filtering based on the observation domain multipath mitigation model,GPS,BDS and GPS＋BDS positioning precision is improved on average by about 42%,38%,and 54%in the north,east,and upward components,respectively.