Characterization of radio propagation channel in Urban Vehicle to Infrastructure environments to support WSNs

Vehicular ad hoc Networks (VANET’s) enable vehicles to communicate with each other (V2V) as well with roadside infrastructure units (V2I) and, nowadays the focus of the VANET’s shifts from research topics to preparing deployment. Various research projects V2V and V2I, where the dynamic nature of vehicular traffic varies on both small and large scale, assume a full-fledge functional wireless communication channel as a prerequisite. Although there is a significant research effort in channel modelling, those works are mainly focused in V2V environments and not much work has been done for V2I.Empirical methods have been widely used to channel characterization for these type of environments. They are very rapid, but lacks of accuracy. On the other hand, deterministic methods are known in the literature to present very good agreement with the channel propagation phenomena in real world.  

This work aims to evaluate some important characteristics of a V2I wireless channel link in a road intersection, using a deterministic simulation model based on an in-house 3D Ray-Launching algorithm, validating its findings with real measurements obtained through the field-test using Wireless Sensor Networks (WSNs). Results of Path Loss, Power Delay Profile, Delay Spread, Doppler Shift and Doppler Spread will be presented. This results are very important in the deployment of a radio-planning V2I environment. Moreover, we will investigate a statistical analysis that let us the comparison with defined statistical models for large and small scale fading.  Finally, we will make some recommendations which will take into account the scope of the simulated scenario and its findings when is compared with the real measurements framework.