A deep knowledge of all propagation effects has become an essential issue to design future communication and navigation systems and optimise their performances. Here, we will target Land Mobile Satellite (LMS) systems, with focus on Global Navigation Satellite Systems (GNSS). The urban environment is one of the most critical for LMS systems, since shadowing, multipath fading and time spreading are often present. This study aims at developing more efficient propagation channel models using physical-statistical approaches. In order to build these models, numerical asymptotic tools are to be used to avoid costly extensive measurements. These tools are theoretically valid for large objects. So, it is necessary to know which level of simplification of the environment is acceptable. Thus, this article performs a rigorous analysis of the influence of small scatterers at different levels of the transmission channel (up to the GNSS receiver), using the exact Method of Moments technique as a reference.
['M. Ait-Ighil', 'J. Lemorton', 'Fernando Perez-Fontan', 'Frederic Lacoste', 'G. Artaud', 'C. Bourga', 'Michel Bousquet']
Simplifying the propagation environment representation for LMS channel modelling