一种新的中长基线GPS RTK解算方法

A new method for medium-range baseline GPS RTK positioning

为了消弱站间星间双差(以下简称双差)对流层延迟和电离层延迟的影响,减小中长基线下卫星升降对模糊度固定成功率的影响,实现中长基线实时动态高精度定位,设计了1种新的中长基线RTK解算方法。该方法以双差非组合观测量为基础,将残余的相对电离层和对流层天顶延迟视为高斯马尔科夫过程进行估计,在卡尔曼滤波方程中,同步估计用户站位置、相对对流层延迟、相对电离层延迟和双差模糊度,设计了部分模糊度固定策略及固定的模糊度进行强制约束,以提高模糊度解算的成功率和可靠性。基于实测数据分析了该方法在模糊度固定和RTK定位精度等方面的性能。结果表明:该方法能有效地改善中长基线模糊度固定的有效性,可提高实际环境的模糊度固定比率,改善定位性能。

In order to eliminate the double-difference ionosphere and troposphere residual error, mitigate the effect of fall-arise of satellite on success rate of ambiguity validation and get the component of medium-range baseline with high accuracy, this paper proposesone method that can estimate ionosphere vertical delay and relative troposphere vertical delay with Gauss-Markova process on basis of double-difference un-combination observation, determines position of rover, relative ionosphere delay, tropo-sphere vertical delay and doubl^difference ambiguity together in extended kalman filter, designs partial ambiguity fixing method and sets fixed ambiguity of previous epoch with high constraints to enhance the reliability of ambiguity resolution In order to val-idate the performance of ambiguity resolution and position accuracy of medium-range RTK when adopted the method mentioned a-bove, experiment is performed based on IGS observational field data, the results show that the method can improve the successful rate of ambiguity resolution of medium-range RTK and get position with good accuracy.