Signal quality checks for multipath detection in GNSS

In GNSS, one of the most important degradations in the signal is caused by the multipath effect, which introduces a bias that impacts the user's position accuracy. The multipath components are attenuated and delayed versions of the transmitted signal, and they are produced by reflections on different obstacles or objects. The aim of this paper is to analyze and compare two multipath detection techniques, namely the Slope Asymmetry Metric (SAM) and the C/N0 evolution, as possible tools to check the quality of the signal in different scenarios. It is shown that while both techniques can provide information about the presence of multipath, the SAM is in general more sensitivity to this effect.