Simulation of GPS localisation based on ray tracing

In recent years, many simulation tools emerged to model the communication of connected vehicles. Thereby, the focus was put on channel modelling, applications or protocols while the localisation due to satellite navigation systems was treated as perfect. The effect of inaccurate positioning, however, was neglected so far. This paper presents an approach to extend an existing simulation framework for radio networks to estimate the localisation accuracy by navigation systems like GPS, GLONASS or Galileo. Therefore the error due multipath components is calculated by ray optical path loss predictions (ray tracing) considering 3D building data together with a well-established model for the ionospheric error.

TOWARDS AN IMPROVED V-VLC OPTICAL CHANNEL MODELLING

Visible Light Communication (VLC) requires better optical channel modelling if it is to be used in vehicular applications. Therefore, the radiation transfer between the transmitter and emitter shall be well defined in all circumstances. An important aspect herein is the determination of the Limiting Photometric Distance (LPD), which characterises the transition between near-field and far-field description of the light source. The LPD allows to determine whether simplified equations can be used in the V-VLC channel model. A first step towards this goal is the analysis of a simple, narrow beam, disk-source with uniform luminance. On-axis, analytical solutions exist. Off-axis, however, no closed loop solutions exist. Therefore, a numerical approach is used, which is validated against on-axis measurements and then expanded to off-axis scenarios. This allows to compute the on- and off-axis LPD of the light source, an important step towards a more accurate description of complex systems for VLC.

Geometry-Based Channel Modelling for Vehicle-to-Vehicle Communication: A Review

Vehicle-to-Vehicle (V2V) communication has received a lot of attention over recent years since it can improve the efficiency and safety of roads for drivers and travellers besides other numerous applications. However dynamic nature of this environment makes it difficult to come up with a suitable wireless communication channel model that can be used in the simulation of any V2V communication system. This paper reviews the recent techniques used for geometry-based stochastic channel modelling for V2V communication. It starts by presenting the various classes of wireless communication channel models available in the literature with more emphasis on the Geometry-Based Stochastic channel Models (GBSM). Then the paper discusses in more detail the state of the art of the regular-shaped and irregular-shaped GBSM for the two- and three-dimensional models. Finally, main challenges are identified and future research directions in this area are recommended.