GPS精密定位中的海潮负荷改正

Ocean Tide Loading Corrections in GPS Precise Positioning

为了正确选用海潮模型和潮波数以提高GPS定位的精度,根据测站位移的海潮负荷改正理论,分别用瑞典?萨斯天文台和日本国家天文台的潮波数据计算了部分IGS站的海潮负荷改正,并对两者的计算结果进行了比较.结果表明,在大洋和内陆,两者结果的差异较小,但在沿海地区差异较大,因此GPS精密定位不仅应考虑测站位移的海潮负荷改正,还应注意选择合适的海潮模型及潮波数.

Based on the theory of site displacement due to ocean tide loading, the site displacements of some IGS （International GPS Service） stations resulted from ocean tide loading were computed respectively using the data given by the Onsala Space Observatory of Sweden and the National Astronomical Observatory of Japan, and comparied in order to select a proper ocean tide model and ocean tide wave number to enhance the GPS （global positioning system） positioning. The comparison shows that to an oceanic or inland IGS station the difference between the two types of corrections is unremarkable, but to a coastal IGS station, the difference is remarkable. So it was believed that in GPS precise positioning, the corrections of site displacements resulted from ocean tide loading should be considered sufficiently, and the feasible selections of ocean tide models and ocean tide wave numbers are important so as to improve the accuracy of the corrections.