In this paper we present a series of monthly gravity field solutions from Gravity Recovery and Climate Experiment(GRACE) range measurements using modified short arc approach,in which the ambiguity of range measureme...In this paper we present a series of monthly gravity field solutions from Gravity Recovery and Climate Experiment(GRACE) range measurements using modified short arc approach,in which the ambiguity of range measurements is eliminated via differentiating two adjacent range measurements.The data used for developing our monthly gravity field model are same as Tongji-GRACEOl model except that the range measurements are used to replace the range rate measurements,and our model is truncated to degree and order 60,spanning Jan.2004 to Dec.2010 also same as Tongji-GRACE01 model.Based on the comparison results of the C_(2,0),C_(2,1),S_(2,1),and C_(15,15),S_(15,15),time series and the global mass change signals as well as the mass change time series in Amazon area of our model with those of Tongji-GRACE01 model,we can conclude that our monthly gravity field model is comparable with Tongji-GRACE01 monthly model.展开更多
本文利用卫星重力反演与模拟软件ANGELS系统(ANalyst of Gravity Estimation with Low-orbit Satellites)对低低跟踪模式的重力卫星的关键载荷精度指标进行了深入分析.模拟结果表明:(1)对短弧长积分法而言,在低低跟踪模式的关键载荷精...本文利用卫星重力反演与模拟软件ANGELS系统(ANalyst of Gravity Estimation with Low-orbit Satellites)对低低跟踪模式的重力卫星的关键载荷精度指标进行了深入分析.模拟结果表明:(1)对短弧长积分法而言,在低低跟踪模式的关键载荷精度指标中,重力场反演精度对星间距离变率精度最为敏感;(2)通过对目前在轨运行GRACE的载荷指标进行分析,发现轨道数据的误差主要影响重力场的低阶部分(约小于25阶),较高阶次部分(约大于26阶)主要受星间距离变率的误差限制;(3)如果下一代低低跟踪模式的重力卫星的目标之一是把重力异常反演精度较GRACE提高约10倍,则在保持轨道高度和GRACE相同的前提下,轨道、星间距离变率和星载加速度计等关键载荷指标需要达到的最低精度分别约为2cm、10nm·s-1和3.0×10-10 m·s-2;(4)轨道精度和混频误差将是影响下一代低低跟踪模式重力卫星重力场恢复能力进一步提高的主要制约因素,距离变率精度和加速度计精度存在盈余.展开更多
基金sponsored by National Natural Science Foundation of China(41474017)National Key Basic Research Program of China(973 Program+3 种基金2012CB957703)sponsored by National Natural Science Foundation of China(41274035)State Key Laboratory of Geodesy and Earth's Dynamics(SKLGED2013-3-2-Z,SKLGED2014-1-3-E)State Key Laboratory of Geo-Information Engineering(SKLGIE2014-M-1-2)
文摘In this paper we present a series of monthly gravity field solutions from Gravity Recovery and Climate Experiment(GRACE) range measurements using modified short arc approach,in which the ambiguity of range measurements is eliminated via differentiating two adjacent range measurements.The data used for developing our monthly gravity field model are same as Tongji-GRACEOl model except that the range measurements are used to replace the range rate measurements,and our model is truncated to degree and order 60,spanning Jan.2004 to Dec.2010 also same as Tongji-GRACE01 model.Based on the comparison results of the C_(2,0),C_(2,1),S_(2,1),and C_(15,15),S_(15,15),time series and the global mass change signals as well as the mass change time series in Amazon area of our model with those of Tongji-GRACE01 model,we can conclude that our monthly gravity field model is comparable with Tongji-GRACE01 monthly model.
文摘本文利用卫星重力反演与模拟软件ANGELS系统(ANalyst of Gravity Estimation with Low-orbit Satellites)对低低跟踪模式的重力卫星的关键载荷精度指标进行了深入分析.模拟结果表明:(1)对短弧长积分法而言,在低低跟踪模式的关键载荷精度指标中,重力场反演精度对星间距离变率精度最为敏感;(2)通过对目前在轨运行GRACE的载荷指标进行分析,发现轨道数据的误差主要影响重力场的低阶部分(约小于25阶),较高阶次部分(约大于26阶)主要受星间距离变率的误差限制;(3)如果下一代低低跟踪模式的重力卫星的目标之一是把重力异常反演精度较GRACE提高约10倍,则在保持轨道高度和GRACE相同的前提下,轨道、星间距离变率和星载加速度计等关键载荷指标需要达到的最低精度分别约为2cm、10nm·s-1和3.0×10-10 m·s-2;(4)轨道精度和混频误差将是影响下一代低低跟踪模式重力卫星重力场恢复能力进一步提高的主要制约因素,距离变率精度和加速度计精度存在盈余.