NTCM广播电离层模型性能评估

对于全球卫星导航系统单频用户而言，广播电离层模型是改正电离层误差的主要方法之一。对NTCM-BC模型、MNTCM-BC模型、NTCM-Klobuchar模型和传统Klobuchar模型的性能进行了对比分析。结果表明，在一个太阳活动周期内，NTCM-BC和MNTCM-BC模型计算的垂直总电子含量精度相当，且精度最高，NTCM-Klobuchar模型次之，Klobuchar模型最低。在低纬度测站，NTCM系列模型较Klobuchar模型最高能减少20 TECU左右的误差。与Klobuchar模型相比，采用NTCM-BC和MNTCM-BC模型进行伪距单点定位，高程精度提高约38%，特别是太阳活动高峰期间，低纬度测站最高能提高3 m左右。

Performance Analysis of NTCM Ionospheric Broadcast Models

The performance of NTCM -BC model, MNTCM -BC model, NTCM -Klobuchar model and traditional Klobuchar model are compared and analyzed. The results show that:In a solar cycle, the accuracy of the vertical total electron content calculated by the NTCM-BC model and MNTCM-BC model is consistent and the highest, followed by the NTCM -Klobuchar model and the Klobuchar model is the lowest. At low-latitude stations, the NTCM models can reduce the error about 20 TECU compared with the Klobuchar model at most. In comparison to use the Klobuchar model, the single point positioning using NTCM-BC and MNTCM-BC model can improve the height accuracy of about 38%, especially at low-latitude stations, the maximum can be reduced by about 3 m.