Characterizing the Degree of LTE Involvement in Supporting Session Continuity in Street Deployment of NR Systems

Abstract

The prospective roll out of recently standardized New Radio (NR) systems operating in millimeter wave frequency band pose unique challenges to network engineers. In this context, the support of NR-based vehicle-to-infrastructure communications is of special interest due to potentially high speeds of user equipment and semi-stochastic dynamic blockage conditions of propagation paths between UE and BR base station (BS). In this conditions even the use of advanced NR functionalities such as multiconnectivity supporting active connections to multiple BSs located nearby may not fully eliminate outages. Thus, to preserve session continuity for UEs located on vehicles a degree of LTE support might be required. In this paper, we quantify the amount of LTE support required to maintain session continuity in street deployment of NR systems supporting multiconnectivity capabilities. Particularly, we demonstrate that it is heavily affected by the traffic conditions, inter-site distance between NR BSs and the degree of multiconnectivity.