Vehicular Communications for ITS: Standardization and Challenges

Intelligent transportation systems (ITS) are fast moving from connected vehicles on the road to autonomous driving. Vehicular communication is a key enabler for the deployment of advanced ITS applications such as platooning and remote vehicle control. DSRC and C-V2X are two key wireless technologies that will play a vital role in the implementation and deployment of an autonomous transport system. We review the current standardization efforts for both of these technologies with a focus on MAC and PHY layers. The automotive industry and research community have been working on new standards - IEEE 802.11bd (for DSRC) and 5G NR V2X (for C-V2X) - to meet the high reliability and low latency requirements of autonomous driving. We also highlight the major changes that have been made to previous standards such as IEEE 802.11p and C-V2X. Finally, we present open challenges that need to be addressed to further improve these standards for vehicular communications.