GRACE-FO加速度计校正方法研究

以2019-01 GRACE-FO实测数据为例，基于动力学方法，采用24 h弧长，通过设置不同的加速度计偏差参数校正策略，分析其对轨道拟合及时变重力场反演结果的影响。结果表明，轨道拟合结果与加速度计校正参数的个数有关，加速度计校正参数个数越多轨道拟合的效果越好，而对于三轴加速度计不同方向采用不同策略时，轨道拟合结果未表现出明显差异；基于本文加速度参数校正策略计算时变重力场时，计算结果表现出明显的差异，结果的好坏与加速度计校正参数有关，同时与不同方向的加速度计参数校正策略相关。综合分析对比发现，对三轴加速度计不同方向采用不同的校正策略会得到不同的结果，其差异主要体现在40阶以上部分，其中Y方向的参数较多时计算结果最优。

Research on Calibration Method of GRACE-FO Accelerometer

Based on GRACE-FO data of January 2019, using the dynamics method with 24 hours arc length, we analyze results of orbital fitting and time-variable gravity field recovery by adopting different accelerometer parameterization strategies. The results show that: the results of orbital fitting are related to the number of parameters in the accelerometer calibration, and the results would be better with the increasing of accelerometer calibrated parameters. Further, there is not the conspicuous improvement in fitting orbit whatever the strategies are used in directions of the three-axis accelerometer. However, the performance of results of the recovered gravity field is influenced by the number of parameters in the accelerometer calibration, and present some differences if we take different strategies at different directions. Through the cases we investigate, the result would be better if we estimate more accelerometer parameters on the Y direction in SRF frame than other cases, especially, at degrees greater than 40.