摘要：Ionospheric delay is the major challenge for Single-Frequency Precise Point Positioning (SF-PPP) users. Therefore, a number of organizations have developed ionospheric delay correction products including the International GNSS Service Global Ionospheric Map (IGS-GIM). Unfortunately, however, the IGS-GIM has a limited spatiotemporal resolution, which in turn limits the PPP accuracy. To overcome this limitation, we develop a regional ionospheric delay correction model for SF-PPP users in Turkey. The developed model has spatial and temporal resolutions of 1º×1º and 15 minutes, respectively. GNSS observations from 6 IGS and EUREF reference stations surrounding Turkey are processed using the PPP module in the Bernese 5.2 software package. The resulting model is tested for PPP applications in Turkey. The PPP positioning accuracy and convergence time obtained through the developed model are assessed and compared with those obtained through the IGS-GIM counterparts. The results reveal that the developed regional ionospheric model is found superior to the IGS-GIM model.
