PRESENTATION OF A MEASUREMENT CAMPAIGN IN UNDERGROUND RAILWAY STATIONS FOR THE VALIDATION OF A HYBRID PROPAGATION MODEL BASED ON RAY-TRACING

International audienceThis paper presents measurement campaign conducted in some train stations in Paris (France) in order to implement and validate a hybrid propagation model in underground railway station environments. In those propagation environments, we can find many geometrical details (pillars, platforms …) and mobile details (trains and passengers) that make the behavior of the radio-waves complex for modelling as they involve multiple reflected, diffracted and scattered waves which can bring about severe degradation of the received signal. The principle of the proposed hybrid model is to combine two approaches: deterministic, based on ray-tracing approach, and statistical ones. On the one hand, the macro geometric characteristics of the train station are considered by the deterministic part; on the other hand, the statistical part considers the spatio-temporal variability (essentially due to the mobility of passengers and trains) and the details which were not considered by the deterministic part (either small objects compared to the wavelength or complex objects)