A Model Based Connectivity Improvement Strategy for Vehicular Ad hoc Networks

This paper presents a connectivity improvement strategy for sparse free-flow Vehicular Ad hoc Networks (VANETs) subject to channel randomness. We first model the connectivity of VANETs in the form of mean broadcast percolation distance based on the equivalent M/G/infinity queue theory. Thereafter, to address the problem of poor connectivity in sparse VANETs, a distributed connectivity improvement strategy based on the deployment of Road Side Units (RSUs) is developed, aiming at improving the connectivity of VANETs to a desired level while minimizing the energy consumption and signal confliction. Simulation studies have been conducted to verify the analytical model and evaluate the efficiency of the proposed strategy, and the results have shown that the connectivity in sparse VANETs has been improved in an efficient and economic way.