LTE-V2X Technology and Standards

Direct communications between vehicles and communication to/from vehicles and roadside infrastructure (vehicle to vehicle and vehicle to/from infrastructure - V2X) has seen strong renewed interest in the last 5 years, with deployments beginning around the world. Using direct device-to-device communication developed in 3GPP, a new V2X radio has been developed that leverages LTE technology to provide excellent performance in non-line-of-sight scenarios without using cellular infrastructure. The first generation of this technology, formally known as PC5 Sidelink, but typically called LTE-V2X (or sometimes C-V2X) is based on Release 14 of the 3GPP standards (and their ETSI counterparts); it enables collision avoidance and other related messages to be delivered with high reliability, low latency, and predictable performance. The messages delivered using LTE-V2X technology can improve safety and driver awareness for a human driver, and lays the groundwork for enhanced performance of automated vehicles in the future. This paper summarizes how LTE-V2X works, describes the standard activities in 3GPP, IEEE, and SAE in different layers of LTE-V2X protocol stack for US deployment, and gives a preview of future standards activities to improve performance and deliver advanced use cases.