GPS Multipath Induced Errors for the Vector Tracking Loop: Insight into Multipath Detection

International audience; Multipath is one of the most serious sources of error in the Global Positioning System (GPS). Multipath distorts the correlation function used for carrier phase and code delay measurements, and therefore induces errors in these measurements and consequently in the calculated positioning solution. This paper aims at characterizing multipath induced tracking errors for a vector tracking loop (VTL). The paper contributes to the characterization of tracking and positioning errors for VTLs by deriving models that allow the analysis of both code and carrier tracking errors with respect to multipath delay, multipath phase and multipath fading frequency. The paper further provides a simple multipath detection technique based on correlator outputs, showing another advantage of the VTL over the scalar tracking loop (STL).