Ionospheric Effect Mitigation for Real-Time Single-Frequency Precise Point Positioning

Precise Point Positioning (PPP) has received increased interest within the GPS community for a number of reasons: simplified field operation, cost-effectiveness, and no base station requirement. PPP with dual-frequency receivers and precise GPS products has demonstrated centimeter to decimeter positioning accuracy. Using real-time precise GPS products, this accuracy is also obtainable in a real-time mode. This paper investigates PPP using single-frequency GPS data which will be of interest to a broad range of applications because the majority of GPS users are using single-frequency GPS receivers. Since the ionospheric effect will be the biggest error source for single-frequency receiver based precise point positioning, different methods for ionospheric effect mitigation will be assessed and compared so that sub-meter positioning accuracy becomes obtainable.