—Due to the dynamic nature of vehicular traffic and
the road surroundings, vehicle-to-vehicle (V2V) propagation characteristics
vary greatly on both small and large scale. Recent
measurements have shown that both large static objects (e.g.,
buildings and foliage) and mobile objects (surrounding vehicles)
have a profound impact on V2V communication. At the same
time, system-level vehicular ad hoc network (VANET) simulators
by and large employ simple statistical propagation models, which
do not account for surrounding objects explicitly. We designed
Geometry-based Efficient propagation Model for V2V communication
(GEMV2), which uses outlines of vehicles, buildings, and
foliage to distinguish the following three types of links: line of
sight (LOS), non-LOS (NLOS) due to vehicles, and NLOS due
to static objects. For each link, GEMV2 calculates the large-scale
signal variations deterministically, whereas the small-scale signal
variations are calculated stochastically based on the number and
size of surrounding objects. We implement GEMV2 in MATLAB
and show that it scales well by using it to simulate radio propagation
for city-wide networks with tens of thousands of vehicles on
commodity hardware. We make the source code of GEMV2 freely
available. Finally, we validate GEMV2 against extensive measurements
performed in urban, suburban, highway, and open-space
environments.