卫星重力反演的短弧长积分法研究

给出了统一求解球谐位系数、弧段边界轨道改正向量、有偏距离改正及加速度计偏差的短弧长积分法,通过对力模型梯度改正减弱了轨道误差对反演地球重力场的影响.采用GRACE卫星1个月的实测轨道及星间距离数据计算表明,短弧长积分法加了梯度改正的精度比不加梯度改正整体提高了近一倍,且该方法在高阶次位系数的精度优于动力学法.基于GRA...

Analysis of short-arc integral approach to recover the Earth's gravitational field

The short-arc integral approach has been derived, which resolves spherical harmonic coefficients, boundary arc orbit correction vector, biased range correction and accelerometer bias simultaneously. The approach reduces the impact of orbit errors on recovery of the Earth's gravitational field by gradient correction of the force models. One month of GRACE satellite orbit and range datum have been used to show that the overall accuracy of the short-arc integral approach with gradient correction is better than the method without gradient correction by a factor of two and the accuracy of the method is better than the dynamical approach in high degree coefficients. An Earth's gravitational field model up to degree and order 120 named SWJTU2010S1 has been resolved by using almost two hundred days of GRACE datum between 2008-01-01~2008-08-01. The precision of the model is better than the model EIGEN-GRACE01S and EIGEN-GRACE02S but lower than EIGEN-CG01C model as shown by internal and external validation.