Performance improvement with low-cost multi-GNSS receivers

In the next five to ten years, the evolution of Global Navigation Satellite Systems (GNSSs) will have a revolutionary impact on the positioning performance. More GNSSs will become available with improved signal characteristics. At the same time, enhancement of receiver technology and algorithms is ongoing. In light of these developments, it is investigated whether high-precision relative positioning with single-frequency receivers will become feasible, and, if so, under which circumstances. We submit that this would open the door to a wide range of applications for instance in the field of mobile Location Based Services for which users do not have professional receivers at their disposal. The closed form expression of the single-frequency Ambiguity Dilution of Precision (ADOP) gives a clear insight into how and to what extent the various factors of the underlying single-frequency model contribute to the overall ambiguity resolution performance. Furthermore, numerical studies indicate that for benign dynamics single-frequency RTK becomes feasible for baselines up to about 10-15 km if GPS+Galileo is used. In this contribution we will present analytical and numerical results. Ambiguity resolution performance as function of number of epochs, receiver noise and baseline length will be analyzed, and compared for ideal circumstances as well as for situations with bad satellite visibility and/or multipath. Furthermore, different next generation GNSS configurations will be considered. Based on the results, it is predicted that for rapid, short baseline cm-level positioning, low-cost single-frequency receivers will become very competitive in comparison to their more expensive dual-frequency cousins.