An investigation of the signal performance of the current and future GNSS in typical urban canyons in Australia using a high fidelity 3D urban model

With the rapid development of spatial information infrastructure in US, Europe, Japan, China and India, there is no doubt that the next generation Global Navigation Satellite Systems (GNSS) will improve the integrity, accuracy, reliability and availability of the position solution. GNSS is becoming an essential element of geospatial infrastructure and consequently part of our daily lives. However, the applicability of GPS in supporting a range of location-sensitive applications such as location based services (LBS) in an urban environment is severely curtailed by the interference of the 3D urban settings. No investigation has been carried out to accurately quantify and reliably evaluate the upcoming improvements like Galileo in typical 3D Australian urban environments. A high-fidelity 3D urban model of Melbourne Central Business District is built using ArcGIS and large scale high-resolution spatial data sets to characterise and gain in-depth understanding of such interferences, and to enable an effective implementation of location-based optimisation alternatives. This model is used to support a comprehensive simulation study of current and future GNSS signal performance, in terms of signal continuity, availability, geometry, positioning accuracy and reliability based on a number of scenarios. The design, structure and major components of the simulator are first outlined. Useful time-stamped spatial patterns of the signal performance over the experimental urban areas have been revealed which are very valuable for supporting LBS applications, such as emergency responses, the optimisation of wireless communication infrastructures and vehicle navigation services.