基于NTCM-BC模型的全球卫星导航系统单频电离层延迟修正  

Ionospheric Delay Correction of Single-frequency for Global Navigation Satellite System Based on NTCM-BC Model

作　　者：胡菡静[1] 王小妮[1] 刘俊婷[1] HU Hanjing;WANG Xiaoni;LIU Junting(Qindao College,Qingdao Technological University,Qingdao 266106)

机构地区：[1]青岛理工大学琴岛学院,青岛266106

出　　处：《空间科学学报》2019年第1期46-54,共9页Chinese Journal of Space Science

基　　金：科技部国际科技合作专项项目资助(2014DFR21280)

摘　　要：选择NTCM-BC模型作为单频电离层延迟修正模型,通过非线性最小二乘拟合的方法,利用提前一天预测的电离层图(COPG文件),计算得到NTCM-BC模型修正系数;利用Klobuchar模型和IGS发布的GIM数据对NTCM-BC模型进行比较和分析.对太阳活动高、中、低年实测数据的分析结果表明:全球平均水平上,NTCM-BC模型的电离层延迟修正性能明显优于Klobuchar模型,NTCM-BC模型的TEC平均误差和均方根误差比Klobuchar模型分别下降了41%和30%;模型的TEC计算误差与太阳活动剧烈程度成正相关,即太阳活动高年模型误差较大,太阳活动低年误差相对较低.相较于磁静日,磁扰日期间Klobuchar模型和NCTM模型的误差均有一定程度的增加.此外,模型的电离层修正误差同时存在明显的纬度、季节和地方时差异.Ionospheric delay is one of dominant factors that affect single-frequency positioning accuracy of Global Navigation Satellite System(GNSS).It is very important for GNSS single-frequency users to study the ionospheric delay correction model of high accuracy.In this paper,an ionospheric correction algorithm called Neustrelitz TEC Broadcast model(NTCM-BC)is chosen as the singlefrequency ionospheric delay correction model.The correction coefficients of NTCM-BC model are obtained by non-linear least square fitting method based on the 1-day predicted ionospheric maps(COPG file).The results of NTCM-BC model have been compared with Klobuchar model and IGSG’s Global Ionosphere Maps(GIM).It can be concluded that,for solar maximum,moderate or minimum,NTCM-BC model can achieve a significantly better performance than Klobuchar model in global average.The mean error and Root Mean Square Error(RMSE)of TEC calculation decrease by 41%and 30%,respectively.The TEC deviations of the two models have positive correlations with solar activity.Compared with the geomagnetic quiet days,the errors of Klobuchar and NTCM-BC models will increase during the geomagnetic perturbed days.Moreover,the correction error depends on latitude,season and local time.

关 键 词：电离层延迟 全球卫星导航系统 非线性最小二乘拟合 KLOBUCHAR模型 NTCM-BC模型 

分 类 号：P323[天文地球—地球物理学]