摘要
B2a信号是北斗三号(BeiDou-3 satellite navigation system,BD-3)新增的高宽带信号,具备非常高的伪距测量精度,适合开展基于全球导航卫星系统反射信号(global navigation satellite system-reflectometry,GNSS-R)的水面高度测量。由于BD-3近两年才开始为全球提供服务,基于BD-3反射信号的研究较少。中国科学院国家空间科学中心研发了具备自主知识产权的GNSS-R接收机,接收机专门增加了BD-3 B2a的捕获跟踪功能,可以对直射和反射B2a信号同时进行捕获和跟踪。接收机同时具备了交叉定标功能,能够有效消除由电缆和接收机通道间差异引起的系统偏差。在中国北京市怀柔开展的岸基实验过程中,累计获取了BD-3 B2a、北斗二号(BeiDou-2 satellite navigation system,BD-2)B1I和全球定位系统(global positioning system,GPS)L1C/A反射信号的相关波形数据,成功反演了水面高度并进行了系统偏差消除。数据处理结果表明,基于BD-3 B2a的水面高度在30 s非相干积分时间条件下反演精度达到了5.9 cm,比BD-2 B1I的高度测量精度提高了13 cm,比GPS L1C/A信号的高度测量精度提高了20 cm。
Objectives:The B2a is a new signal of BeiDou-3(BD-3)with high-bandwidth and high pseudorange measurement precision,therefore,it is suitable for GNSS-R water surface altimetry.There were few studying based on the BD-3 reflected signal,due to the BD-3 system just began to provide worldwide services in the past two years.Methods:The National Space Science Center(NSSC)has developed a GNSSR receiver with independent intellectual property supporting the BD-3 B2a capture and tracking functions,which can obtain and track both direct and reflected B2a signals.B2a signals are difficult to capture due to its long PRN code.One B2a assistant approach is proposed and implemented that the shorter B1I signals are first obtained and tracked,then the B2a signals can be correctly captured using B1I auxiliary information with shorter acquisition time.One cross calibration system is included by the receiver,which can effectively eliminate the system biases caused by the delays of different cables and receiver channels.Results:During the shore-based experiment carried out at Huairou in Beijing in 2019,the correlation waveforms of the BD-3 B2a,BD-2 B1I and GPS L1 C/A reflected signals were accumulated.The water surface height was successfully retrieved and the systematic biases was eliminated effectively.The water surface height results show that the inversion precision based on BD-3 B2a reaches 5.9 cm with the non-coherent integration time of 30 s.Conclusions:The height precision has been improved by 13 cm than BD-2 B1I signal and20 cm than GPS L1 C/A signal.This verification experiment expands the application research of BD-3 system in GNSS-R water surface altimetry and lays the foundation for the development of subsequent tasks.
作者
王冬伟
孙越强
王先毅
白伟华
夏俊明
杜起飞
蔡跃荣
孟祥广
吴春俊
刘成
乔颢
李福
WANG Dongwei;SUN Yueqiang;WANG Xianyi;BAI Weihua;XIA Junming;DU Qifei;CAI Yuerong;MENG Xiangguang;WU Chunjun;LIU Cheng;QIAO Hao;LI Fu(National Space Science Center,Chinese Academy of Sciences,Beijing 100190,China;Beijing Key Laboratory of Space Environment Exploration,Beijing 100190,China;Key Laboratory of Environmental Space Situation Awareness Technology,Chinese Academy of Sciences,Beijing 100190,China;Joint Laboratory on Occultations for Atmosphere and Climate,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100190,China)
出处
《武汉大学学报(信息科学版)》
EI
CAS
CSCD
北大核心
2022年第11期1878-1886,共9页
Geomatics and Information Science of Wuhan University
基金
国家自然科学基金(41775034,41405040,41505030,41606206,41405039)
中国科学院科研装备研制项目(YZ201129)
中科院青年创新促进会基金(2018180)。