Uiterst betrouwbare UAV-ondersteunde voertuigcommunicatienetwerken

Urban wireless networks face growing challenges in providing ultra-reliable, low-latency connectivity in dense, dynamic environments, particularly for future Intelligent Transportation Systems (ITS). In this context, 6G networks are expected to integrate Non-Terrestrial Networks (NTNs), where Uncrewed Aerial Vehicles (UAVs) can enhance coverage and reliability through flexible deployment and improved Line-of-Sight (LoS) conditions. This PhD thesis investigates reliable Air-to-Ground (A2G) communication for UAVs operating as both Aerial Base Stations (ABSs) and Aerial User Equipment (AUEs) in urban environments. For UAVs as ABSs, a 3D geometry-based LoS probability (PLoS) model is developed using ITU built-up parameters. Unlike existing models that rely solely on elevation angle, the proposed approach incorporates elevation, azimuth, and user location, yielding improved accuracy and strong agreement with simulation and ray-tracing results across both structured and irregular urban layouts. The thesis further demonstrates that user heterogeneity, such as pedestrians versus vehicles, significantly affects path loss and should be explicitly modeled. For UAVs as AUEs, the thesis presents a measurement-based, trajectory-aware characterization of the A2G channel using real-world UAV data. Furthermore, a Context-Aware Smart Handover (CASH) protocol is proposed, showing a substantial reduction in handovers and outages compared to conventional 5G A3-based schemes. Overall, this thesis combines analytical modeling, simulation, and measurements to improve the reliability and predictability of UAV-assisted vehicular communication, contributing to the design of future 6G-enabled ITS.