Development of GNSS Type Processing for the Characterization of the Mobile Propagation Channel

Abstract: Mobile communication systems are undergoing significant development on increasingly wide frequency bands (5G in particular). To support this development, a detailed characterization of the propagation of electromagnetic waves in L, S and C band between a station (satellite, airborne or ground) and a mobile platform is necessary to analyze and model the phenomena that have a decisive impact on the performance, availability and operability of systems. The environments of interest are complex (urban environment for example) and include a wide range of different elements (buildings, pylons, trees etc.) that will have an impact on the signal received by a mobile in reception. These needs motivated the development of a simulator using an enhanced hybrid physicalstatistical model for Land Mobile Satellite (LMS) propagation Channel. This simulator has been developed by a PhD student and presented in [Ait+13]. This study has been conducted by the ONERA on behalf of the CNES. The Simplified CHannel for Urban Navigation (SCHUN) ensure a wideband characterization of the channel, with realistic multipath modelling and is dedicated to the testing of GNSS systems. However, this model must be validated in S and C bands and measurement campaigns have been carried out to compare simulated and experimental data. In this work, the data corresponding to a trajectory with alternatively LOS and NLOS situation in an urban canyon have been derived from a measurement campaign carried out in Saint-Lary in S and C frequency bands. The post-processing of the data performed in the S frequency band has been performed using a pre-existing algorithm implemented at ONERA relying upon acquisition and tracking signal processing principles of GNSS. This trajectory has been simulated along with its surroundings using SCHUN. The Channel Impulse Response has been computed to derive multipath characteristics. Comparisons have been made between simulations and experimental data and have shown great concordance. Future works would be first to extend this comparison to C-bands and then to statistically simulate a virtual city corresponding to the town in which the experiment has been carried out to complete the validation.