摘要
为了保证北斗系统广域差分服务的平稳过渡,北斗三号系统(BDS-3)通过GEO卫星B1I/B3I信号播发北斗二号协议广域差分改正信息,包括等效钟差改正数与格网点电离层信息。分析了增加BDS-3卫星后,等效钟差改正数和格网点电离层信息的特征,并对BDS-2和BDS-3的用户差分距离误差(UDRE)进行了对比。联合BDS-2和BDS-3实测数据,对BDS-3广域差分服务定位精度进行了评估。分析结果表明:BDS-2卫星广播星历空间信号用户等效距离误差(UERE)约为1 m,经过等效钟差改正数后,用户差分距离误差约为0.3 m;BDS-3卫星广播星历空间信号用户等效距离误差约为0.4 m,经过等效钟差改正数后,用户差分距离误差约为0.2 m。等效钟差改正数可以修正广播电文更新带来的空间信号阶跃误差,显著提升卫星空间信号精度。与基本导航系统播发的Klobuchar 8模型,广域差分系统所播发的格网点电离层信息可将电离层误差修正精度提高约18%。与单独BDS-2卫星相比,BDS-2/BDS-3卫星联合条件下,基本导航的单频用户和双频用户定位精度可分别提升26%和41%;广域差分服务的单频用户定位精度为2.4 m,双频用户定位精度为1.7 m,单频用户和双频用户定位精度分别提升13%和41%。
In order to ensure the smooth transition of the wide-area differential service of the Beidou system,the Beidou-3 System(BDS-3)uses D2 navigation message on GEO satellite to broadcast the equivalent clock correction and ionospheric grid information on B1I/B3I frequency.This paper analyzes the characteristics of the equivalent clock correction and ionospheric grid information after adding the BDS-3 satellite,and compares the User Differential Range Error(UDRE)of satellite between the BDS-2 and the BDS-3.Combined with the measured data of BDS-2 and BDS-3,this paper also evaluates the positioning accuracy of widearea differential service of BDS-3.The analysis results show that,after using the equivalent clock correction,the User Equivalent Range Error(UERE)of the BDS-2 satellite changes from approximately 1 meter to approximately 0.3 meters,while the BDS-3 satellite UERE changes from approximately 0.4 meters to approximately 0.2 meters.The results show that the equivalent clock correction can correct the space signal step error brought by the update of the broadcast message,and significantly improve the satellite space signal accuracy.Compared with the Klobuchar 8 model broadcast by the basic navigation system,the ionospheric grid information broadcast by the wide-area differential system can improve the accuracy of ionospheric error correction by about 18%.In comparison with BDS-2 single system,the accuracy of single-frequency positioning for BDS-2/BDS-3 can be improved by 26%,while that of dual-frequency positioning can be improved by 41%.The positioning accuracy of single-frequency users for wide-area differential services is 2.4 meters,and the positioning accuracy of dual-frequency users is 1.7 meters,which is improved by 13%and 41%respectively.
作者
田秋凝
曹月玲
胡小工
唐成盼
郭睿
杨宇飞
TIAN Qiuning;CAO Yueling;HU Xiaogong;TANG Chengpan;GUO Rui;YANG Yufei(Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China;University of Chinese Academy of Sciences,Beijing 100049,China;PLA 32021 Troops,Beijing 100094,China;Beijing Satellite Navigation Center,Beijing 100094,China)
出处
《北京航空航天大学学报》
EI
CAS
CSCD
北大核心
2021年第5期967-976,共10页
Journal of Beijing University of Aeronautics and Astronautics
基金
国家重点研发计划(2016YFB0501900)
国家自然科学基金(41674041,11203059,41804030,41874039)。
