• GUERMAH BASSMA STRS Laboratory, National Institute of Posts and Telecommunication Rabat, Morocco
  • SADIKI TAYEB Universite Internationale de Rabat (UIR), Faculty of Computing and Logistics, TICLab Sala El Jadida, Morocco
  • EL GHAZI HASSAN STRS Laboratory, National Institute of Posts and Telecommunication Rabat, Morocco
  • REBOUL SERGE LISIC Laboratory, University of the Littoral Opal Coast, ULCO
  • AHOUZI ESMAIL STRS Laboratory, National Institute of Posts and Telecommunication Rabat, Morocco


GNSS, Hard environment, Map-Matching, Masking, Multipath, NLOS


In Global Navigation Satellite systems (GNSS), the performances of classical localization methods show a signicant degradation in constrained environments (urban and indoor environments), due to Non-Line-of-Sight(NLOS) and Multipath phenomena aecting GNSS signal. In order to improve positioning accuracy in hard environment, this paper aims to propose an approach to compute and adapt the NLOS and Multipath error model to GNSS signal reception conditions. The approach aims rstly to propose a Map-Matching based-technique to compute Multipath and NLOS errors in real time positioning, secondly, to test adequacy of these errors with the most used models in the literature and nally to model the Multipath and NLOS errors using Gaussian mixture noise. As a result, we have shown that a Gaussian, Rayleigh and Uniform model were not be able to model eectively Multipath and NLOS errors and we have demonstrated that a Gaussian mixture model can approximate these errors and improve positioning accuracy in urban environment.



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