Reducing Collision Probability with Multihop Diversity for Vehicle-to-Roadside Networks
Kizilrmak, Refik Caglar and Torkamani-Azar, Mastaneh
Loading
Abstract
Implementation of high performance, low-latency cooperative collision
avoidance (CCA) protocols for Vehicular Ad hoc NETworks (VANETs) is of
major importance for public safety organizations and automobile
manufacturers. In this study, we examine a vehicle-to-roadside (V2R)
transmission scheme in which the intermediate roadside terminal
amplifies and forwards the broadcasted warning signal and acts as a
relay to provide diversity to the destination vehicle. We compare the
bit-errorrate (BER) and packet-error-rate (PER) performances of multihop
V2R and single-hop vehicle-to-vehicle (V2V) transmission schemes. We
further present a Markov chain traffic model in order to observe the
impact of the improved error-rate performance on the collision
probability. We assume the inter-vehicle spacing follows exponential
distribution, and then draw a stochastic model considering the
probabilities of successful message reception, transmission delay and
drivers' reaction time. Numerical results reveal that the chance of
collision in the V2R scheme is considerably less than the single-hop V2V
case for equal message sizes sent over a large range of inter-vehicle
spacing. This setting plays a vital role in wireless intervehicle
warning applications such as collision avoidance for automated and
semi-automated highway systems.... Show more Show less