5G Functional Architecture and Signaling Enhancements to Support Path Management for eV2X

Enhanced vehicle-to-everything (eV2X) communication is one of the most challenging use cases that the fifth generation (5G) of cellular mobile communications must address. In particular, eV2X includes some 5G vehicular applications targeting fully autonomous driving which require ultra-high reliability. The usual approach to providing vehicular communication based on single-connectivity transmission, for instance, through the direct link between vehicles (PC5 interface), often fails at guaranteeing the required reliability. To solve such a problem, in this paper, we consider a scheme where the radio path followed by eV2X messages can be proactively and dynamically configured to either transmit through a single interface (chosen between the PC5 and the Uu interface for infrastructure-based communication) or through both interfaces simultaneously, depending on the requirements and particular situation. After describing some path management general considerations, we propose a new network function and a procedure to enhance the current capabilities of the 3GPP 5G system. Next, we propose different architectures to support our proposal following the four 5G eV2X architectural options defined by the 3GPP. For each alternative, the necessary signaling for the dynamic configuration of the radio paths is detailed. Finally, an exemplary use case of our proposal is presented in detail to illustrate the feasibility of our proposed functional architectures, and, for that use case, system-level simulation results are provided to demonstrate the benefit achieved with dynamic path management.