摘要
卫星重力技术的进步为建立高精度的全球重力场模型提供了可能,该技术包括卫星测高、卫星重力梯度和卫星跟踪卫星等。而在建立扰动场模型的过程中一般要采用移去 恢复技术,该技术的核心是从已知的重力数据中减去根据参考重力场模型计算的扰动场元,并在最后的成果中加入移去部分对应的扰动场元。但在移去、恢复的过程中往往利用扰动场元在格网中心点的值乘以某平滑因子代替扰动场元在该格网上的平均值,不可避免地引入了系统误差。从勒让德微分方程和勒让德函数的定义出发,详细研究了利用重力场模型计算扰动场元在格网上的平均值的方法,该方法在利用卫星测高资料反演海域重力异常中的应用表明,重力异常的精度得到了进一步提高。
With the development of satellitegravimetry technology which includes satellite altimetry, SST, SGG and so on, it is possible to establish a high precise global potential model from the satellitegravimetry data and the terrestrial gravity anomalies using the removerestore procedure. The key of removerestore procedure is to remove a disturbing potential element from a reference potential model and restore related disturbing potential element in the end. But during the removerestore procedure some scholars take advantage of the product of a smooth factor with the disturbing potential quantities at the center of a grid instead of the mean one over the grid, which must yield some systematic errors. Starting with Legendre differential equation and the definition of Legendre function, this paper discusses in details the computational method of the mean value of any disturbing quantity over a grid. The document applies the method in predicting the gravity anomalies over the offshore sea from satellite altimetry data, which improves the precision of the result.
出处
《测绘学报》
EI
CSCD
北大核心
2003年第2期108-113,共6页
Acta Geodaetica et Cartographica Sinica
