Improving the Performance of Next-Generation Vehicular Safety Messages Communication With Relay-Assisted Protocol

Abstract

Vehicular ad hoc networks (VANETs) are becoming popular due to autonomy and intelligent transportation systems (ITSs), and they play a key role in enabling the broader concept of the Internet of Vehicles (IoV). Moreover, VANETs will have cutting-edge improvements with the emergence of 5G and 6G technologies. Recent research has concentrated on reducing delay and increasing throughput. To improve the performance of VANETs, a novel MIMO-OFDM-based cooperative vehicular safety message communication mechanism is proposed in this work. Optimal relay selection in cooperative communication is essential in maximizing system performance. This article presents an optimal relay selection mechanism based on the signal-to-noise ratio (SNR) and vehicle velocity for VANETs. First, an SNR-based relay selection mechanism is analyzed separately, and then an optimal relay selection mechanism is suggested based on vehicle velocity. To maximize the benefits of multiple-input-multiple-output (MIMO) and orthogonal frequency-division multiplexing (OFDM), both are combined, and a novel access mechanism is suggested to accommodate MIMO with OFDM. A Markov chain-based mathematical model is derived. Nakagami-m fading channels are considered in the analysis. The performance is evaluated in terms of successful transmission probability, outage probability, throughput, and delay terms. Simulation of urban mobility (SUMO) generates a microscopic mobility model for practical application. For the sake of comparison and to highlight the performance achievable gains, comparisons with existing mechanisms are presented, which reveal significant improvement in performance. The simulation results reveal that significant improvements can be obtained with the proposed system relative to other existing schemes.