Adaptive Broadcast Scheduling Scheme for High-definition Map Tile Dissemination in Vehicular Networks

Autonomous vehicles require precise and reliable data for critical functions like localization and navigation. High-Definition (HD) maps are essential, segmented into vari-ous layers (each with varying roles and lifespans) and verti-cally structured into 'tiles' that encapsulate these layers. Effi-ciently disseminating these tiles via Road Side Units (RSUs) in Vehicle-to-Everything (V2X) networks is challenging. An efficient dissemination method must minimize both the Turn Around Time (TAT)-the time from a tile request to receipt-and the inci-dence of schedule misses, which is when a vehicle does not receive a tile before its deadline, impacting reliability and performance. This paper introduces an Adaptive Broadcast Scheduling (ABS) scheme tailored for HD maps, factoring in layer priority, request popularity, and deadlines. Experimental studies show that ABS outperforms conventional periodic broadcast by cutting schedule misses by over 50% and reducing TAT to milliseconds.