【摘要】 根据经典的球谐函数方法,为满足正交化要求,观测数据需要覆盖整个球面,而对于地表局部测量数据,则无法应用球谐方法解算重力场模型。针对此问题,采用Slepian局部谱分析方法解算中国大陆范围内的实测重力场变化数据,并以GOCE卫星球谐函数解作为已知模型,评估由于实际陆地重力测点的非均匀分布对球谐函数解的误差影响。通过计算多个阶次中国大陆局部范围的Slepian基函数分布;采用GOCE卫星获得重力场模型的前72阶球谐系数作为已知结果,评价实际测点非均匀分布的解算有效性,并针对中国大陆地区采用Slepian基函数进行解算,通过模型对比选择最优截段项数;针对2005—2008年中国大陆地区流动重力测量获得的重力场变化信号进行解算,获得了72阶重力场变化模型。更多还原

【Abstract】 For the purpose of calculating the gravity field model through spherical harmonic method only based on local measurements,it calculated that the measured gravity field data in China’s mainland by Slepian local spectrum method,and also it evaluated that the error effected by the non-uniformity of measured points by the known spherical harmonic model of GOCE satellite datasets.Firstly it calculated that the Slepian basis functions in China’s mainland and took the 72 order spherical harmonic model of GOCE satellite to evaluate the effective of the method in non-uniformity of measured points.Then,it recalculated that the gravity filed model by the Slepian localized spectral approach based on the resample points of Chinese mainland,and determined the gravity field variation model of Chinese mainland using the repeated gravity measure datasets from 2005 to 2008.更多还原