Geospatial professionals must be aware of how their tools and programs work to evaluate their results and diagnose potential problems. This part of the four part series on real-time GNSS positioning will attempt to present and explain in simple terms how real time positioning works. After a short look at the current and near future state of the GNSS constellations, the concept of ambiguity resolution will be discussed noting some techniques used to resolve the unknown integer number of cycles using differencing and other methodology. Highlighted sections of the NGS guidelines for single base positioning will be will be shown and static positioning options will be briefly contrasted to the precisions obtainable with real-time methods. Additionally, a short look will be taken at the augmented autonomous GNSS positioning developments that are approaching usable survey-grade precisions with shortening initialization times.
Objectives
- The near future of GNSS
- High accuracy carrier phase positioning by ambiguity resolution
- Using the NGS real time guidelines
- Understanding “differencing”
- Real time versus static positioning
- Augmented autonomous precise point positioning developments
