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From the perspective of an individual vehicle, the prediction of a “slow-down” or shockwave event on a freeway can help the driver reduce potential collision risks, enhance the driving experience, and reduce the cost of energy consumption and vehicle maintenance. From the perspective of traffic management, shockwave prediction may help regulate traffic flow effectively and allow for the response to (non-recurrent) incidents in a timely manner. In this paper, two real-time prediction algorithms are proposed and investigated, which are based on the high-resolution information provided from a set of connected vehicles within the communication range of the host vehicle. Both methods are able to predict the “slow-down” event under high traffic density at 3.51 seconds (on average) earlier than its occurrence. Both algorithm performances degrade with the decrease of the traffic density and penetration rate of the connected vehicles.

Scalable communication is of utmost importance for reliable dissemination of time-sensitive information in cooperative vehicular ad-hoc networks (VANETs), which is, in turn, an essential prerequisite for the proper operation of the critical cooperative safety applications. The model-based communication (MBC) is a recently-explored scalability solution proposed in the literature, which has shown a promising potential to reduce the channel congestion to a great extent. In this work, based on the MBC notion, a technology-agnostic hybrid model selection policy for Vehicle-to-Everything (V2X) communication is proposed which benefits from the characteristics of the non-parametric Bayesian inference techniques, specifically Gaussian Processes. The results show the effectiveness of the proposed communication architecture on both reducing the required message exchange rate and increasing the remote agent tracking precision., Accepted for Oral Presentation at the 13th IEEE Systems Conference (SysCon 2019)

Heterogeneous nature of the vehicular networks, which results from the co-existence of human-driven, semi-automated, and fully autonomous vehicles, is a challenging phenomenon toward the realization of the intelligent transportation systems with an acceptable level of safety, comfort, and efficiency. Safety applications highly suffer from communication resource limitations, specifically in dense and congested vehicular networks. The idea of model-based communication (MBC) has been recently proposed to address this issue. In this work, we propose Gaussian Process-based Stochastic Hybrid System with Cumulative Relevant History (CRH-GP-SHS) framework, which is a hierarchical stochastic hybrid modeling structure, built upon a non-parametric Bayesian inference method, i.e. Gaussian processes. This framework is proposed in order to be employed within the MBC context to jointly model driver/vehicle behavior as a stochastic object. Non-parametric Bayesian methods relieve the limitations imposed by non-evolutionary model structures and enable the proposed framework to properly capture different stochastic behaviors. The performance of the proposed CRH-GP-SHS framework at the inter-mode level has been evaluated over a set of realistic lane change maneuvers from NGSIM-US101 dataset. The results show a noticeable performance improvement for GP in comparison to the baseline constant speed model, specifically in critical situations such as highly congested networks. Moreover, an augmented model has also been proposed which is a composition of GP and constant speed models and capable of capturing the driver behavior under various network reliability conditions., This work has been accepted in 2018 IEEE Connected and Automated Vehicles Symposium (CAVS 2018)

Backbone wireless mesh networking concept has been developed in order to provide higher bandwidth, better QoS (less delay and jitter) and larger coverage range compared with previous network types. These factors should be balanced in an appropriate way in order to satisfy mentioned goals. In this paper an optimization framework has been proposed in order to maximize throughput according to upper bound allowable delay. Problem has been studied in two cases with fixed and variable duration transmission intervals and results have been compared. Also secondary interference avoidance constraints based on IEEE 802.11 MAC protocol model have been discussed.