基于BDS-3的陆地探测一号星间基线高精度解算方法  

High-Precision Inter-Satellite Baseline Determination Method for Lutan-1 Based on BDS-3

作　　者：张宇 赵齐乐[1] 蒋科材 郭向 李敏[1] ZHANG Yu;ZHAO Qile;JIANG Kecai;GUO Xiang;LI Min(GNSS Research Center,Wuhan University,Wuhan 430079,China;National Precise Gravity Measurement Facility,Huazhong University of Science and Technology,Wuhan 430074,China;Center for Gravitational Experiment,School of Physics,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]武汉大学卫星导航定位技术研究中心,湖北武汉430079 [2]华中科技大学精密重力测量国家重大科技基础设施,湖北武汉430074 [3]华中科技大学物理学院引力中心,湖北武汉430074

出　　处：《武汉大学学报（信息科学版）》2024年第10期1763-1769,共7页Geomatics and Information Science of Wuhan University

基　　金：国家自然科学基金(42030109,42204020)。

摘　　要：陆地探测一号(Lutan-1,LT-1)是中国首个L波段干涉合成孔径雷达(interferometry synthetic aperture radar,InSAR)低轨编队卫星任务,高精度的星间基线是InSAR处理和应用的关键。研究了低轨卫星编队动力学精密基线解算方法和星间双差模糊度固定方法,并分析了LT-1 A/B双星星载北斗卫星导航系统(BeiDou satellite navigation system,BDS)(B1C、B2a)和GPS(L1、L2)在精密基线解算中的贡献。实验结果表明,与GPS相比,BDS-3的B1C和B2a观测值相位和伪距观测值残差明显更小,表明其信号精度更高。基于GPS、BDS和GPS/BDS联合解的基线重叠精度分别为0.8 mm、0.6 mm和0.5 mm,BDS基线精度比GPS提高25%,并且联合GPS/BDS可进一步提高基线精度。利用GPS和BDS解算的基线间互差精度为1 mm,表明单BDS-3系统可以实现1 mm级的低轨卫星编队精密基线确定。Objectives Lutan-1(LT-1)is the first formation-flying mission of China,enabling interfero‑metry synthetic aperture radar(InSAR)in the L-band.High-precision inter-satellite baseline is crucial for InSAR processing and application.Methods We investigate the dynamic precise baseline solution method and the inter-satellite double-difference ambiguity fixing method of low-orbit formation satellite,and analyze the contribution of BDS-3(B1C,B2a)and GPS(L1,L2)observation of LT-1 A;B in precise baseline determination.Results The results show that compared with GPS,the residuals of B1C and B2a observations of BDS-3 are significantly smaller,suggesting a higher signal accuracy.The baseline overlap accuracies of GPS-based,BDS-based,and GPS;BDS combined solutions are 0.8 mm,0.6 mm,and 0.5 mm,respectively.The BDS-based baseline accuracy is 25%higher than that of GPS,and the GPS;BDS combined solution can further improve the baseline accuracy by 37.5%and 16.7%relative to the GPS-and BDS-baselines.The baseline difference between the GPS-based and BDS-based baseline solutions is 1 mm in 3 dimensional directions.Conclusions The analysis suggests that the single BDS-3 system can achieve precise baseline determination for low-orbit formation satellites at the 1 mm level and combined GPS;BDS solution will further improve the accuracy than single-system solution.

关 键 词：B1C/B2a信号 精密基线确定 模糊度固定 LT-1卫星 

分 类 号：P228[天文地球—大地测量学与测量工程]