【摘要】 为探测我国HY-2A卫星高度计海面高测量绝对偏差及其在轨运行状态,本文利用GNSS浮标星下点同步测量和验潮资料海面高传递方法在山东千里岩和珠海担杆岛海域开展定标研究。为验证GNSS浮标定标方法的准确性,还对国外卫星Jason-2和Saral进行了定标实验。实验表明GNSS浮标绝对海面高测量精度达2cm,对Jason-2和Saral高度计多个周期定标得到的海面高偏差均值分别为5.7cm和-2.3cm,与国际专门定标场的结果符合较好。2014年9月和2015年5月HY-2A卫星高度计浮标定标结果分别是-65cm和-91cm,因两次结果差异显著,故又利用千里岩验潮站资料对HY-2A卫星高度计第56至73周期进行了定标分析,结果证明HY-2A卫星海面高存在约-51cm/a的漂移,置信度为95%的回归分析表明浮标和验潮定标结果符合。本文研究结果表明在我国尚无专门定标场的情况下,可利用GNSS浮标对我国高度计实施灵活、精准的在轨绝对定标,在有高度计轨迹经过验潮站的情况下可使用验潮资料结合精密大地水准面模型进行绝对定标。更多还原

【Abstract】 In order to determine the absolute bias of HY-2A sea surface height(SSH)and monitor the on-orbit working conditions of HY-2ASatellite altimeter,we conducted the absolute calibration experiments in the Qianliyan and Dangan area of China.In this study we adopted two independent methods which are deploying the GNSS buoy under satellite tracks for simultaneous observation and using the tide gauge data combined with the precise geoid model.In addition,for verifying the accuracy of the GNSS buoy calibration method,the Jason-2and Saral Satellite altimeters,which were already calibrated by international calibration sites,were also calibrated using the same GNSS buoy.The SSH accuracy of the GNSS buoy is estimated to be about 2cm by comparison with the tide gauge data.The absolute biases of Jason-2and Saral calibrated by the GNSS buoy are 5.7cm and-2.3cm,which are in accordance with the results of the international calibration sites.According to the GNSS buoy the SSH absolute biases for HY-2are determined to be-65 cm in September 2014and-91 cm in May 2015,which are changed significantly for the two experiments.Thus in order to quantify the drift velocity of HY-2ASSH and assess the on-orbit working conditions of HY-2ASatellite altimeter more accurately,we used long time series of tide gauge data of the Qianliyan oceanic station to calibrate the cycles 56 to 73of HY-2A.The drift phenomenon of HY-2ASSH is confirmed by the long-time series altimeter data and the drift velocity is estimated to be-51cm/a.By the regression analysis with 95%confidence coefficient,the GNSS buoy calibration result of HY-2Ais in good accordance with the result from the tide gauge data.From the result of this paper,we conclude that under the condition of no dedicate calibration site the altimeter absolute bias could be determined by GNSS buoy with flexibility and high accuracy and the drift of absolute bias could be quantified by the tide gauge data combined with the precise geoid mode.更多还原