How to Improve GNSS Positioning Quality of Service for Demanding ITS in City Environments by Using 3D Digital Maps

The paper presents two different methods, so-called light and heavy, for taking into account the knowledge of the 3D environment of a vehicle in a city, where propagation phenomena can cause severe errors in positioning computation. The two methods make use of digital maps, but in a different way. The paper presents in details the methods to compare their results in terms of hidden satellites detection and applies the light method on a real test site in Nantes to demonstrate the gain in terms of accuracy of the final position.