利用国际卫星导航系统服务以及中国大陆构造环境监测网络的实测数据,构建电离层球谐模型SHAG(Shanghai Astronomical Observatory globalmodel),并与欧洲定轨中心(Center for Orbit Determination in Europe,CODE)提供的电离层数据比较,得到如下结果:11在全球范围内,二者解算的卫星硬件延迟误差的均方根值(root mean square,RMS)为0.11ns,观测站硬件延迟误差的RMS为0.59ns;2)对于中国大陆及邻区,二者电离层总电子含量(total electronic content,TEC)的RMS为2.1TECu(1TECu=0.35ns),但SHAG模型解算观测站TEC更接近GNSS双频解算的结果;31通过与数字测高仪的观测资料比较,发现SHAG模型解算的电离层结果可较好地描述不同观测站区域的电离层变化趋势。综合结果表明,中国大陆构造环境监测网络数据的大量引入改善了SHAG模型的中国区域电离层特性,能较好地描述中国区域电离层空间分布及变化特征。
In this paper, the ionospheric SHAG (Shanghai Astronomical Observatory global model) model is established on the spherical harmonic function algorithm driven by Global Positioning System (GPS) datum from International Global Navigation Satellite System Service (IGS) as well as China Crustal Movement Observation Network (CMONOC). Comparing the products of SHAG model with those of Center for Orbit Determination in Europe (CODE), analytical results shows: 1) all over the world, the RMS of GPS satellites different code bias (DCB) is 0.11 ns and the RMS of receiver stations DCB is 0.59 ns; 2) within the scope of China and adjacent areas, the RMS of the total electronic content of those two model is 2.1 TECu; 3) comparing the VTEC of CODE and SHAG the observation result of with ionosonde, we find that the VTEC of SHAG model is better to describe the TEC variety. In conclusion, SHAG model can reflect the changing of TEC over China and adjacent areas correctly.