2012 | OriginalPaper | Chapter
Connectivity of Vehicular Ad Hoc Networks in Downtown Scenarios
Activate our intelligent search to find suitable subject content or patents.
Select sections of text to find matching patents with Artificial Intelligence. powered by
Select sections of text to find additional relevant content using AI-assisted search. powered by
We study the connectivity in vehicular ad-hoc networks in a downtown scenario, where the mobility of vehicles is constrained on a lattice-shaped road network. We theoretically investigate the connectivity under the Poisson-positioning assumption, where vehicles are positioned according to a Poisson process on each road at any arbitrary instants. We find that the Poisson-positioning assumption allows the existence of the finite critical-vehicle density; that is, if (and only if) the density of vehicles is greater than the finite critical density, then there exists a large (theoretically infinite) cluster of vehicles and an arbitrary pair of vehicles in the cluster is connected in single or multiple hops. Under the Poisson-positioning assumption, we derive two approximation formulas for the critical density, which are given as a function of the transmission range of each vehicle and the distance between intersections. We also consider the connectivity under more realistic movement patterns of vehicles where the Poisson-positioning assumption does not hold. We numerically find that, even in non-Poisson-positioning cases, there exists the critical vehicle density, which is larger than the one under the Poisson-positioning assumption. The effectiveness of deploying roadside-relay stations to provide better connectivity between vehicles is also investigated.