GNC-MAC: Grouping and Network Coding-assisted MAC for Reliable Group-casting in V2X

Vehicle-to-everything (V2X) technology has been proposed as a leading step toward road safety improvement and intelligent transportation systems, and these vehicular-related applications rely on reliable ways of communication. For the regions which are not covered by communication infrastructure or deployment of centralized controllers are not straightforward, vehicle-to-vehicle (V2V) communication is a potential solution. Reliability is crucial in vehicular ad hoc networks (VANETs) from beacon broadcasting and security aspects. Group-casting and applying multi-hop communication can ensure reliability in V2X systems. In this paper, a distributed grouping and network coding-assisted medium access control protocol (GNC- MAC) is proposed to support reliable group-casting. We propose a new grouping protocol by combining preamble-based feedback mechanism, multi-hop communication, and network coding to improve group-casting reliability. Extensive simulations have been conducted to show the performance gain of the GNC- MAC protocol compared to the existing 5G cellular vehicle-to- everything (C-V2X) MAC protocol in a wide range of scenarios.