摘要
针对电离层区域模型构建时段内变化剧烈所导致的相邻时段球谐函数模型不连续问题,提出一种基于相邻时段约束策略的区域电离层模型构建方法:利用非差非组合法提取欧洲地区的全球导航卫星系统(GNSS)观测站电离层延迟信息,采取不同低阶数的区域球谐函数构建模型,确定区域模型的适用低阶数;提出利用相邻时段的模型信息对当前时段约束的策略,提升低阶区域球谐函数模型精度;最终在确定适用阶数和相邻时段约束策略的基础上获取用户端的电离层约束信息,分析附加电离层约束的实时动态精密单点定位(PPP-RTK)用户端定位性能。实验结果表明:1)二阶区域球谐函数模型在满足电离层建模精度的同时,可以其待估参数少的优势加快PPP-RTK服务端解算效率。2)基于相邻时段约束策略改进的区域低阶球谐模型,能解决因电离层变化较大引起的模型不连续等问题,磁暴日外符合精度平均提高率为2.00%,内符合精度平均提高率为4.50%。3)附加电离层约束的PPP-RTK磁暴日定位精度水平方向优于2.00 cm,高程优于2.70 cm,收敛时间优于9.0 min;磁静日定位精度水平方向优于1.80 cm,高程优于2.50 cm,收敛时间优于7.0 min。能够满足大众用户对厘米级实时位置服务的需求。
Aiming at the problem of discontinuity of spherical harmonic model caused by drastic changes of ionospheric adjacent periods,the paper proposed a regional ionospheric model construction method based on adjacent periods constraint strategy:with the extracted ionospheric delay information of European global navigation satellite system(GNSS)stations based on the non-difference and non-combination method,the spherical harmonic model was set different order to determine the suitable low order;then,the strategy of using the adjacent periods information to constrain the current period was proposed to improve the accuracy of the low order regional spherical model;finally,based on the determination of the suitable order and the adjacent period constraint strategy,the user positioning performance of precise point positioning-real time kinematic(PPP-RTK)with additional ionospheric constraints was analyzed.Experimental results showed that:1)The second-order regional spherical harmonic model could not only meet the accuracy of ionospheric modeling,but also speed up the efficiency of PPP-RTK server with the advantage of less parameters to be estimated.2)Based on the adjacent period constraint strategy,the problem of discontinuity model caused by drastic changes in the ionosphere could be solved,the average improvement rate of the external accord accuracy would be 2.00%,and the average improvement rate of the internal accord accuracy would be 4.50%.3)The PPP-RTK positioning accuracy of magnetic storm day would be better than 2.00 cm in horizontal direction,better than 2.70 cm in elevation,and the convergence time better than 9.0 minutes;moreover,the positioning accuracy of magnetic static day would be better than 1.80 cm in horizontal,better than 2.50 cm in elevation,and the convergence time better than 7.0 minutes,which could meet the centimeter-level real-time location service demand of public users.
作者
张涛
刘站科
郝宗泽
刘艳辉
ZHANG Tao;LIU Zhanke;HAO Zongze;LIU Yanhui(The First Geodetic Surveying Brigade of Ministry of Natural Resources,Xi'an 710054,China;Chinese Academy of Surveying and Mapping,Beijing 100830,China)
出处
《导航定位学报》
北大核心
2025年第5期165-175,共11页
Journal of Navigation and Positioning
基金
国家重点研发计划项目(2021YFC3000504)
国家自然科学基金重点基金项目(41930535)
陕西测绘地理信息局科技创新项目(SCK2023-02)。
