Performance Analysis of BDGIM

Abstract

According to the three-step construction plan of BDS, the global signal will cover worldwide by June of 2020. The BDGIM model is innovatively proposed to correct the single frequency ionospheric delay in BDS. As a new model, it is necessary to analyze the performance of BDGIM. Based on the ionosphere data of CODE, this paper compares the performance of BDGIM with that of BDSKlob, GPSKlob and NeQuickG in the aspects of space, time and the effects on single point positioning. The results show that compared with the other ionospheric models, BDGIM model is closest to CODE. Excluding the high latitude area, the BDGIM model is the best among all the single ionospheric models in the other areas. NeQuickG model shows the best performance in high latitude area and become worse in low and mid latitude areas. Compared with the BDSKlob model of BDS-2, the BDGIM model of BDS-3 has been greatly improved. The accuracy of BDGIM model in the Northern hemisphere is better than that in the Southern, and the correction ratio is better than 75% over China and exceed 65% worldwide. Compared with the SPP results of using BDSKlob model, the positioning accuracy based on BDGIM model is improved by 25% and the positioning improvement in high latitude area is more obvious, which almost reached 45%.