Performance Monitoring of BeiDou Navigation Satellite System Ionospheric Grid

The correction principle, definition and usage of the ionospheric grid of BeiDou navigation satellite system (BDS) are introduced. Based on the BDS ionospheric grid information received by BDS receivers, and compared with ionosphere delay evaluated using double-frequency measurements, the correction performance of BDS ionospheric grid in different latitudes and in different periods is evaluated. In addition, the wide-area differential positioning results of BDS B1I in Beijing, Chengdu, and Sanya are analyzed. Real data analysis indicates that, the average correction accuracy of B1I using BDS ionospheric grid is 91.17 %, the average correction accuracy is 0.32 m, and the horizontal positioning accuracy of B1I differential positioning is 4.54 m (95 confidence level), the height positioning accuracy is 5.32 m (95 % confidence level).