海道测量定位中对流层延迟差分估计技术研究

A Differential Estimation Technique of Troposphere Delay for Precise Positioning in Hydrographic Surveying

为削弱海上对流层延迟对高精度海道测量的影响,提出了一种基于差分改正思想的对流层延迟估计方法。首先,以Saastamoinen模型作为先验值,采用精密单点定位技术估算对流层改正量。将天顶延迟的剩余误差作为待定参数,用Kalman滤波估计对流层的残余量;然后,分别估计基准站和移动站的对流层延迟,作为差分计算的初值代入差分解算模型中,从而求得海上移动站的精确位置。实测数据表明,相对于常规动态解,基于对流层差分改正的定位技术改善了移动站的定位精度,其中,垂直方向的精度提高了17.6%。

To reduce the influence of troposphere delay for precise positioning in hydrographic surveying, a novel estimation method of troposphere delay was proposed based on the differ- ential estimation idea. Taking the value originating from a Saastamoinen model as the priori value, the amended value of the troposphere delay was calculated through precise point posi- tioning. Taking the residual error of the zenith troposphere delay as the unknown parameter, the delay error was determined by Kalman filtering. Then, the troposphere delay of the base station and the marine rover were estimated respectively. These delay values were then en- tered into the differential estimation model as the initial values, and the precise position of the rover was determined. The result of boat and airplane experiments show that as com- pared to the conventional kinematic solution, the locattional precision for boats and the air- planes is improved by the differential estimation technique of troposphere delay. Additional- ly, the precision in the vertical direction increased about 17.6%.