Optimal Trajectory Design for Unmanned Aerial Vehicle Cargo Pickup and Delivery System Based on Radio Map

Unmanned Aerial Vehicle (UAV) cargo delivery systems have emerged as a promising solution for efficient and timely delivery. Previous studies often based their UAV logistics delivery strategies on Manhattan distance. However, these methods face difficulties when dealing with the complexities of multi-user scenarios, low-altitude communication, and the non-convex nature of the problem. Innovative approaches are needed to overcome these challenges. This study explores a multi-user UAV cargo delivery system, where a cellular-connected UAV efficiently collects and distributes packages within a delivery area. Balancing task completion speed and reliable communication with ground base stations (GBS) poses challenges due to the problem's highly nonconvex nature. To address this, we propose a two-step approach. Initially, leveraging a graph-theoretic method under communication quality constraints, we determine the shortest path between points ensuring communication connectivity. Subsequently, considering pickup and delivery with capacity constraints based on communication connectivity (PDPCC), we present an efficient solution for obtaining the optimal task sequence and integrating it with the shortest paths. Our numerical results demonstrate the algorithm's efficacy in reducing delivery task completion time while ensuring continuous online UAV operation through maintained communication connectivity.