中文摘要：

提出了一种恢复地球重力场并同时改善部分轨道初始参数的方法——基线法。给出了基线法的基本原理,推导了基线参数与直角坐标形式参数的相互转换公式,分析了星间距离和距离变率对基线参数的敏感性。分别用基线法和经典动力学法处理了一组GRACE实际观测数据,结果表明,采用基线法较经典动力学法得到了一个精度更高的地球重力场模型,其大地水准面累积误差（最高60阶）减少了3 cm。

英文摘要：

We present a new method,named baseline method,which used for recovering the Earth＇s gravity field and improving some parameters of initial orbital vector simultaneously.The principle of the baseline method is introduced.The formulae of transforming between baseline parameters and typical Cartesian parameters are deduced.And the sensitivities of inter-satellite observations to baseline parameters are analyzed.The two Earth＇s gravity field models are recovered from GRACE data by typical method and baseline method respectively,and their accuracies are evaluated.The results show that the accumulated geoid undulation error from baseline method is less 3 cm than the one from typical method.