title: Investigating the feasibility of vehicular communications with modern wireless access technologies
Creators: name: Clancy, Joseph Sean
Publisher: name: University of Galway
Year: 2024
Subjects: subject: Vehicular Communications
subject: V2X
subject: Vehicle-to-Everything
subject: Wireless Communications
subject: Cellular
subject: 4G LTE
subject: 5G NR
subject: DSRC
subject: 3GPP
subject: Engineering
subject: Electrical and Electronic Engineering
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Vehicle-to-Everything (V2X) communications is a technology intended to facilitate information exchange among connected vehicles, targeting improved road safety and traffic efficiency. The wireless access segment of V2X communications is responsible for providing this connectivity to vehicles. Of the portfolio of wireless communication technologies currently in use today, Dedicated Short-Range Communication (DSRC) and Cellular Vehicle-to-Everything Communications (C-V2X) are the primary candidates to enable wireless access for V2X communications. Despite its potential benefits, V2X communications has not been widely adopted to date, indicating lingering technical challenges and thus motivating the primary research objective of this thesis: to investigate and characterise the wireless access challenges facing V2X communications as an industry vertical. Firstly, a review of the state-of-the-art in wireless access technologies for V2X communications is provided, beginning with an overview of V2X communications, its history, and standardisation. This is followed by a description of the two primary wireless access technologies, DSRC and C-V2X, and the presentation of a comprehensive review of the literature surrounding their candidacy. Results indicate that C-V2X is likely to be the most appropriate candidate wireless access technology due to its wider application support and potential for growth. Finally, active research areas that have the potential to address the challenges identified in the literature review are discussed. Secondly, a novel dataset is generated to evaluate and characterise the capabilities of early 5G New Radio (NR) cellular deployments, thus characterising the potential challenges towards the large-scale adoption of V2X communications. Results demonstrate that new 5G NR deployments can indeed outperform the existing 4G Long Term Evolution (LTE) cellular system in ideal conditions. However, results also indicate that the new 5G NR deployments are subject to a significant degree of variability and are much less reliable than the existing 4G LTE system. In particular, handovers were found to be a significant source of unreliability in V2X scenarios, with the inter-RAT (Radio Access Technology) handover type emerging as the primary contributor due to demanding control signalling and radio management requirements. Lastly, given the challenges associated with large-scale deployment of V2X communications, a small-scale Vehicle-to-Infrastructure (V2I) application intended for safety-critical use cases is proposed as a potential solution. The feasibility of the network architectures of the proposed V2I system is evaluated with particular consideration of the trade-offs associated with implementation constraints, i.e. cost, performance and security. Results show that the system is indeed feasible, however, several open questions about the system performance requirements of such safety-critical use cases remain. In summary, this thesis indicates that while non-safety-critical V2X applications are feasible with current wireless access technologies, significant advancements will be required to support safety-critical applications at scale. To this end, a number of potential solutions are proposed to bolster the capabilities and capacity of current networks and thus provide a path towards the large-scale adoption of V2X communications technology.