Heterogeneous LTE/DSRC Approach to Support Real-time Vehicular Communications

Vehicle-to-everything (V2X) communications have become a key enabler for future autonomous driving by providing sensing and cooperation abilities beyond traditional on-board sensors. The main candidate technologies for V2X communications are dedicated short range communication (DSRC)/IEEE 802.11p and long-term evolution (LTE), each of which has its own strengths and weaknesses. DSRC provides low-latency direct connectivity, but suffers from serious link degradation and reliability issues. On the other hand, LTE is able to provide high capacity data transmission, while its latency remains an issue due to the long transmission time interval. Integrating these two radio technologies as a heterogeneous solution is promising to complement each other and support V2X applications with differentiated service requirements. This paper proposes a service-aware radio access technology (RAT) selection algorithm that enables a heterogeneous LTE/DSRC solution, where LTE and/or DSRC are selected according to services. Each vehicle is assumed to be equipped with both LTE and DSRC interfaces. The heterogeneous solution selects RAT based on the services requirements with consideration of the networks performance. The solution is implemented with integration of the C-ITS standard and validated through the OMNet++ and SUMO based network simulator. A see-through scenario, where a fleet of vehicles require real-time video data sharing to assist efficient driving, is considered. The simulation results demonstrate that the proposed approach outperforms the purely DSRC approach significantly and is able to simultaneously support safety message transmission with low latency, video streaming with high bandwidth requirements, and other applications with different service requirements.