5G NR Sidelink Multi-Hop Transmission in Public Safety and Factory Automation Scenarios

The deployment of D2D communications (also known as ProSe or sidelink transmissions) in cellular networks benefits from proximity, multi-hop, and spatial reuse gains. In this article, we first describe the main advancements of NR sidelink compared to LTE-A sidelink. Then, we run a simulation campaign to test D2D-based ProSe for public safety and factory automation scenarios with their mission-critical requirements and ultra-reliable low-latency communications, respectively. A preliminary study on NR sidelink usage for both considered use cases is performed, aiming to identify the main advantages and disadvantages thereof. Finally, important future directions for the NR sidelink development from a standardization perspective are highlighted.