岸基BDS-R海面测高及其观测值加权方法  

Shore-based BDS-R sea surface altimetry and weighting method of its observed values

作　　者：侯金华 贺凯飞[1] 高凡[2,3] 储倜 吴宇 HOU Jinhua;HE Kaifei;GAO Fan;CHU Ti;WU Yu(College of Oceanography and Space Informatics,China University of Petroleum(East China),Qingdao 266580,China;Institute of Space Science,Shandong University,Weihai 264209,China;School of Space Science and Physics,Shandong University,Weihai 264209,China)

机构地区：[1]中国石油大学(华东)海洋与空间信息学院,青岛266580 [2]山东大学空间科学研究院,威海264209 [3]山东大学空间科学与物理学院,威海264209

出　　处：《北京航空航天大学学报》2024年第3期1015-1026,共12页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家自然科学基金(42174021);山东省自然科学基金(ZR2021MD060)。

摘　　要：随着北斗三号卫星导航系统(BDS-3)的全球组网完成,其反射信号在全球导航卫星系统反射测量(GNSS-R)海面测高领域的应用也更加广泛。为研究BDS-3 B1C反射信号码延迟海面测高性能,以及多星测高数据组合方法,进行了基于B1C码信号的双天线岸基北斗卫星导航系统反射测量(BDS-R)码延迟海面测高实验。利用自主研发的GNSS-R测高软件接收机对实验数据进行事后处理,将测高结果与岸基同步观测的雷达测高仪所测海面高度值进行对比分析,并基于反射信号信噪比(SNR)和卫星高度角加权的方法对多星测高观测值进行加权计算,评定BDS-R海面测高精度。结果表明:自主研发的GNSS-R测高软件接收机可用于海面测高,基于B1C码信号的BDS-R海面测高精度有达到分米级的可能性;根据10 s观测数据平滑可以得到,单颗卫星B1C码信号最优测高结果的均方根误差(RMSE)为0.634 m,平均绝对误差(MAE)为0.507 m,多星测高观测值加权组合最优结果的均方根误差为0.538 m,平均绝对误差为0.500 m,明显优于单星观测精度,最大可提升70%,最小可提升17%;针对同一信号多星GNSS-R测高数据加权方法,应用综合考虑卫星高度角和反射信号信噪比的加权模型优于其他加权模型,测高精度分别比信噪比分段模型、正弦函数模型、指数函数模型、等权模型提升9.4%、9.5%、20.5%、35.2%。With the completion of the global networking of BeiDou-3 satellite navigation system(BDS-3),its reflected signals are more and more widely used in the field of global navigation satellite system-reflectometry(GNSS-R)sea surface altimetry.A dual antenna coastal BDS-reflectometry(BDS-R)sea surface altimetry experiment based on BDS-3 B1C reflected signal code-level delay and the combination method of multi-satellite altimetry observations was carried out in order to investigate the performance of sea surface altimetry based on these two factors.The independently developed GNSS-R altimetry software receiver is used for post-processing of the experimental data,and the experimental results and the sea surface height of the shore-based synchronous observation radar altimeter were compared and analyzed to evaluate the accuracy of BDS-R sea surface altimetry.Additionally,the multi-satellite altimetry readings are combined using a weighted technique based on the signal-to-noise ratio(SNR)of the reflected signal and satellite elevation.The results show that the independently developed GNSS-R software receiver can be used for sea surface altimetry,and it is possible that the precision of BDS-R sea surface measurement based on B1C code can reach decimeter level.According to the result of moving averages with 10 s,the root mean square error(RMSE)and mean absolute error(MAE)of single satellite sea surface altimetry are 0.634 m and 0.507 m respectively,and the RMSE and MAE of the weighted combination of multi-satellite observations are 0.538 m and 0.500 m respectively.The observation accuracy of the latter is obviously better than that of the former,and the maximum and minimum observation accuracy can be improved by 70%and 17%respectively.The weighted model with thorough consideration of satellite elevation angle and reflected signal SNR is superior to other weighted models for the same signal multi-satellite GNSS-R altimetry data weighting method,and its measurement accuracy is improved by 9.4%,9.5%,20.5%,35.2%compared with SNR

关 键 词：B1C 北斗卫星导航系统反射测量 软件接收机 海面测高 加权模型 

分 类 号：V221.3[航空宇航科学与技术—飞行器设计] TB553[理学—物理]