Attenuation Caused by Obstructing Vehicles in V ANETs
The connectivity among vehicles is affected by obstructions either static (e.g., buildings, vegetation, hills) or mobile (other vehicles on the road). The low height of antennas onboard the vehicles implies that the optical line of sight (LOS) can be obstructed by the obstructions, in particular by the mobile obstructions causing disconnection among vehicles even within the single hop transmission range. In this work, the channel modeling for vehicular communication scenario is investigated in detail. Multiple knife-edge diffraction is proposed to account for attenuation caused by vehicle along the propagation path. The vehicular communication scenario is simulated in the ns-3 network simulator with four categories of vehicles and the attenuation loss is calculated. The simulation results confirm that vehicles as obstructions can be a major source of signal attenuation and a single vehicle can cause attenuation up to 20 dB in the road scenario.