摘要
针对北斗导航与广域差分服务分区综合改正数缺失和切换造成的用户端定位精度恶化和重新收敛,提出一种同时适用于系统端改正数生成和用户端定位的分区综合改正数拟合算法。通过多个临近分区的分区综合改正数与待拟合分区的改正信息之间的双差残差对待拟合分区综合改正数进行拟合,可有效填补分区综合改正数的中断弧段。利用MGEX(Multi-GNSS Experiment)监测站的数据对拟合出的分区改正参数进行定位效果评估。采用拟合分区综合改正数进行动态定位,定位精度能达到水平0.20 m,高程0.44 m,较使用原始分区综合改正数精度仅降低8%左右,但能够有效保持定位结果的连续性和精度,在提高系统服务完整性及用户定位结果的可靠性方面具有积极意义。
The BeiDou Navigation Satellite System(BDS) provides wide area differential service(WADS)for users in China territory by broadcasting equivalent satellite clock, orbit correction, ionospheric grid information and zone correction through Geostationary Earth Orbit(GEO) satellites. By using WADS corrections correctly, users with code observations can get meter-level positioning accuracy while carrier phase users can get decimeter-level result. However, the imperfection and discontinuity of zone correction bring a negative influence upon positioning. Aiming at solving the precision deterioration and positioning re-convergence caused by the discontinuity of zone correction, a fitting algorithm is proposed for zone correction generation and user’s positioning. The fitting algorithm is established on the basis of the stability of double-differenced zone corrections. By fixing the zone correction of one reference satellite and the double-differenced bias between multiple zones and satellites, the correction gap can be filled up successfully.Then, the validity of the algorithm and the performance of fitting zone correction was evaluated by differential positioning experiments using observations from six Multi-GNSS Experiment(MGEX) stations within zone correction service range under kinematic PPP mode. Experiment results show that although the positioning precision of fitting zone corrections, which is 0.20 m and 0.44 m for horizontal and vertical components respectively, is slightly inferior to the result derived by using the original corrections. In the discontinuous periods of zone correction, the positioning results are much more stable and continuous, and without positioning re-convergence. With no additional information used in correction fitting, the algorithm can be used for the zone correction generation period and position, which will improve the service integrity and positioning reliability.
作者
王兵浩
周建华
陈俊平
张益泽
王阿昊
WANG Binghao;ZHOU Jianhua;CHEN Junping;ZHANG Yize;WANG Ahao(School of Geospace Information,Information Engineering University,Zhengzhou 450001,China;Beijing Satellite Navigation Center,Beijing 100094,China;Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China;Department of Maritime Systems Engineering School of Astronomy and Space Science,University of Chinese Academy of Sciences,Beijing 100049,China;Department of Maritime Systrem Engineering,Tokyo University of Marine Science and Technology,Tokyo 135-8533,Japan;College of Surveying and Geo-Informatics,Tongji University,Shanghai 200092,China)
出处
《武汉大学学报(信息科学版)》
EI
CSCD
北大核心
2020年第4期565-573,共9页
Geomatics and Information Science of Wuhan University
基金
国家自然科学基金(11673050)
国家重点研发计划(2018YFB0504300)。