Traffic monitoring and incident detection through VANETs

Abstract

Road traffic monitoring is one of the key applications in the Intelligent Transport System field. New technologies are now provided in this field and among the most relevant ones there is the DSRC (Dedicated Short Range Communication) set of protocols and standards where vehicles wirelessly communicate. In this paper, we deal with the application of Vehicular Ad-Hoc Networks to road traffic monitoring and we present the design of two distributed protocols based on the DSRC. A realistic simulation of a main expressway in Rome, Italy, is implemented and the performances of the two proposed monitoring methodologies are evaluated in case of regular traffic conditions and in case of a car accident. In both cases the protocols are able to capture in a very quick time (few seconds) the current traffic conditions even on a quite long road of about 70 km. A discussion about the impact of the market penetration rate of the on-board DSRC devices on the protocols performance is also provided. © 2014 IEEE

On the level of detail of synthetic highway traffic necessary to vehicular networking studies

“…The synthetic traffic input feed relies instead on probability distributions of the inter-arrival or inter-spacing between subsequent vehicles to generate the inflow into the simulated highway segment. The distributions employed in the literature to that end vary, and include deterministic [7], [14], exponential [12] and log-normal [21] arrivals, up to generative models for mixture distributions [15]. Also the initial speed is derived from a probability distribution, typically uniform [10].…”

“…The literature on highway vehicular simulation features heterogeneous mobility models. Some works use low complexity representations [10], [11], whereas others rely on dedicated simulators [7], [14]. In some cases, researchers developed proprietary tools tailored to their needs [6].…”

“…However, the existing literature does not provide an answer in the case of highway environments. Some works propose to use aggregate statistics to describe vehicle inflows [7], [10]- [14], whereas others employ fine-grained, per-vehicle traffic count data [6]. Some works employ stochastic models of drivers' behavior [10]- [13], whereas other leverage complex microscopic models [6], [7], [14].…”

“…Some works propose to use aggregate statistics to describe vehicle inflows [7], [10]- [14], whereas others employ fine-grained, per-vehicle traffic count data [6]. Some works employ stochastic models of drivers' behavior [10]- [13], whereas other leverage complex microscopic models [6], [7], [14]. Many works neglect the presence of entry and exit ramps [6], [10]- [13], whereas other consider them [7], [14].…”

“…Some works employ stochastic models of drivers' behavior [10]- [13], whereas other leverage complex microscopic models [6], [7], [14]. Many works neglect the presence of entry and exit ramps [6], [10]- [13], whereas other consider them [7], [14]. Overall, which of the settings above can be deemed correct for the evaluation of vehicular networking solutions for highway environments -and which are not -remains unclear.…”