基于条件平差的网络RTK电离层改正数偏差修正  

Correction of ionospheric correction deviation in network RTK based on conditional adjustment

作　　者：石鑫 张熙 成兵 柯元英 雷传金 SHI Xin;ZHANG Xi;CHENG Bing;KE Yuanying;LEI Chuanjin(The Third Geodetic Surveying Brigade of Ministry of Natural Resources,Chengdu 610000,China)

机构地区：[1]自然资源部第三大地测量队,成都610000

出　　处：《全球定位系统》2024年第5期103-109,共7页Gnss World of China

基　　金：自然资源部第三大地测量队科技支撑项目(2023KJ01);四川测绘地理信息局科技支撑项目(2023KJ02);四川省测绘地理信息学会科技开放基金(CCX202320);四川省交通运输科技项目(2023-A-14)。

摘　　要：本文针对午后太阳辐射较大时段网络实时动态定位(real-time kinematic,RTK)电离层延迟建模精度不高的问题,提出了一种基于条件平差的电离层改正数偏差修正方法.利用闭合三角形单元中三条基线双差电离层延迟理论闭合差为0这一条件,对建模得到的电离层改正数进行平差处理,修正其偏差,并对修正过程中的权阵确定方案进行了相关讨论.实验表明:当电离层改正数模型值精度不高时,修正算法可以有效提高电离层改正数的精度,同时基于已知基线的模糊度固定情况来确定权阵能达到较好的修正效果,电离层改正数偏差最大值减小58.0%,精度总体提高51.1%.Aiming at the problem of low accuracy of ionospheric delay modelling in the afternoon in network RTK,a deviation correction method for ionospheric correction values based on conditional adjustment is proposed,using the condition that the theoretical closure difference of the three baselines in the triangle with double-difference ionospheric delays is 0,to adjust the ionospheric correction values obtained by modelling,and the scheme of determining the weighting array in the correction process is discussed.The experiments show that the correction algorithm can effectively improve the accuracy of ionospheric correction when the accuracy of the ionospheric correction model is not high,and at the same time,the determination of the weight array based on the ambiguity fixing of the known baselines can achieve a better correction effect,with the maximum value of the deviation of the ionospheric correction value reduced by 58.0 percent and the overall accuracy improved by 51.1 percent.

关 键 词：网络实时动态定位(RTK) 电离层改正数 偏差修正 条件平差 VRS GNSS 

分 类 号：P228.4[天文地球—大地测量学与测量工程]