Abstract—A thorough understanding of the communications
channel between vehicles is essential for realistic modeling of
Vehicular Ad Hoc Networks (VANETs) and the development of
related technology and applications. The impact of vehicles as
obstacles on vehicle-to-vehicle (V2V) communication has been
largely neglected in VANET research, especially in simulations.
Useful models accounting for vehicles as obstacles must satisfy
a number of requirements, most notably accurate positioning,
realistic mobility patterns, realistic propagation characteristics,
and manageable complexity. We present a model that satisfies
all of these requirements. Vehicles are modeled as physical
obstacles affecting the V2V communication. The proposed model
accounts for vehicles as three-dimensional obstacles and takes
into account their impact on the LOS obstruction, received signal
power, and the packet reception rate. We utilize two real world
highway datasets collected via stereoscopic aerial photography
to test our proposed model, and we confirm the importance of
modeling the effects of obstructing vehicles through experimental
measurements. Our results show considerable obstruction of
LOS due to vehicles. By obstructing the LOS, vehicles induce
significant attenuation and packet loss. The algorithm behind the
proposed model allows for computationally efficient implementation
in VANET simulators. It is also shown that by modeling the
vehicles as obstacles, significant realism can be added to existing
simulators with clear implications on the design of upper layer
protocols.
Index Terms—VANET, vehicle-to-vehicle communication, simulation,
signal propagation modeling, channel model