GPS buoy methodology is one of the main calibration methodologies for altimeter sea surface height calibration. This study introduces the results of the Qinglan calibration campaign for the HY-2A and Jason-2 altimeter...GPS buoy methodology is one of the main calibration methodologies for altimeter sea surface height calibration. This study introduces the results of the Qinglan calibration campaign for the HY-2A and Jason-2 altimeters. It took place in two time slices;one was from August to September 2014, and the other was in July 2015. One GPS buoy and two GPS reference stations were used in this campaign. The GPS data were processed using the real-time kinematic (RTK) technique. The fi nal error budget estimate when measuring the sea surface height (SSH) with a GPS buoy was better than 3.5 cm. Using the GPS buoy, the altimeter bias estimate was about -2.3 cm for the Jason-2 Geophysical Data Record (GDR) Version ‘D' and from -53.5 cm to -75.6 cm for the HY-2A Interim Geophysical Data Record (IGDR). The bias estimates for Jason-2 GDR-D are similar to the estimates from dedicated calibration sites such as the Harvest Platform, the Crete Site and the Bass Strait site. The bias estimates for HY-2A IGDR agree well with the results from the Crete calibration site. The results for the HY-2A altimeter bias estimated by the GPS buoy were verifi ed by cross-calibration, and they agreed well with the results from the global analysis method.展开更多
针对GPS、卫星激光测距(satellite laser ranging,SLR)和天线电定位(doppler orbitography and radiopositioning integrated by satellite,DORIS)3种不同的观测手段,讨论姿态模型误差对定轨的影响,以SLR验证、轨道重叠和外部轨道对比3...针对GPS、卫星激光测距(satellite laser ranging,SLR)和天线电定位(doppler orbitography and radiopositioning integrated by satellite,DORIS)3种不同的观测手段,讨论姿态模型误差对定轨的影响,以SLR验证、轨道重叠和外部轨道对比3种方法评定无姿态数据条件下的定轨精度,并基于该结果讨论不同轨道叠加方法的效果。以Jason-2卫星为例,在详细讨论GPS、SLR和DORIS的定轨策略基础上并基于实测数据进行了试验,试验结果表明,Jason-2卫星姿态模型误差对DORIS、GPS和SLR轨道影响分别为0.040m、0.036m和0.033m;无姿态数据定轨时,DORIS定轨结果略优于GPS和SLR,SLR定轨精度略差;基于轨道重叠结果加权,对GPS、SLR和DORIS轨道进行轨道叠加可以达到比较好的效果,通过与JPL轨道比较,其轨道径向精度可优于2cm。展开更多
基金Supported by the National Key R&D Program of China(No.2016YFC1401003)the National Natural Science Foundation of China(Nos.41406204,41501417)the Marine Public Welfare Project of China(No.201305032-3)
文摘GPS buoy methodology is one of the main calibration methodologies for altimeter sea surface height calibration. This study introduces the results of the Qinglan calibration campaign for the HY-2A and Jason-2 altimeters. It took place in two time slices;one was from August to September 2014, and the other was in July 2015. One GPS buoy and two GPS reference stations were used in this campaign. The GPS data were processed using the real-time kinematic (RTK) technique. The fi nal error budget estimate when measuring the sea surface height (SSH) with a GPS buoy was better than 3.5 cm. Using the GPS buoy, the altimeter bias estimate was about -2.3 cm for the Jason-2 Geophysical Data Record (GDR) Version ‘D' and from -53.5 cm to -75.6 cm for the HY-2A Interim Geophysical Data Record (IGDR). The bias estimates for Jason-2 GDR-D are similar to the estimates from dedicated calibration sites such as the Harvest Platform, the Crete Site and the Bass Strait site. The bias estimates for HY-2A IGDR agree well with the results from the Crete calibration site. The results for the HY-2A altimeter bias estimated by the GPS buoy were verifi ed by cross-calibration, and they agreed well with the results from the global analysis method.
文摘针对GPS、卫星激光测距(satellite laser ranging,SLR)和天线电定位(doppler orbitography and radiopositioning integrated by satellite,DORIS)3种不同的观测手段,讨论姿态模型误差对定轨的影响,以SLR验证、轨道重叠和外部轨道对比3种方法评定无姿态数据条件下的定轨精度,并基于该结果讨论不同轨道叠加方法的效果。以Jason-2卫星为例,在详细讨论GPS、SLR和DORIS的定轨策略基础上并基于实测数据进行了试验,试验结果表明,Jason-2卫星姿态模型误差对DORIS、GPS和SLR轨道影响分别为0.040m、0.036m和0.033m;无姿态数据定轨时,DORIS定轨结果略优于GPS和SLR,SLR定轨精度略差;基于轨道重叠结果加权,对GPS、SLR和DORIS轨道进行轨道叠加可以达到比较好的效果,通过与JPL轨道比较,其轨道径向精度可优于2cm。
