精密定轨中三类经验加速度的有效建模方法

根据瞬时速度脉冲、逐段常量经验加速度和周期性摄动加速度模型的特点，分别给出敏感矩阵的有效计算方法，以及最小二乘批处理的设计矩阵和法方程矩阵的分块结构。该建模方法将灵敏度矩阵数值积分规模和存储规模降为O(n)，而传统方法为O(n 2)。应用GRACE-A星载GPS观测数据对法方程的计算效率测试，结果表明：对于瞬时速度脉冲和逐段常量经验加速度模型，当采用伪距观测量时，法方程构建效率提高1倍；当采用伪距加载波相位观测量时，效率提高3.5倍。对于周期性摄动加速度模型，效率没有明显提高，主要原因在于模型参数较少，矩阵分块建模方法的优越性尚未体现。

Modeling and Analysis of Three Types of Empirical Accelerations in Precise Orbit Determination

In terms of the characteristics of instantaneous velocity pulses, piecewise constant empirical accelerations and periodic perturbation accelerationmodels, effective computational methods are proposed for calculating the sensitivity matrices related to model parameters respectively. Meanwhile,design matrices and normal equation matrices are expressed in the form of different partitioned sub-matrices. The computational amount of numerical integration and data storage of effective methods grows with O(n), butconventional methodsdo with O(n 2). The GRACE-A on board GPS observation data has been used to evaluate the computionalefficiency of normal equationby use of the proposed methods.Results show that for instantaneous velocity pulses and piecewise constant empirical accelerations, the computational efficiency of modeling normal matricesis increasedonce when ionosphere-free linear combination of pseudorange observations is used, and the efficiency is increased 3.5 times when ionosphere-free linear combination of pseudorange and carrier phase observations is used. However, there is no obvious improvement for periodic perturbations because the number of parameters is small compared with the other two models.