QoE Based Network Deployment and Caching Placement for Cache-Enabling UAV Networks

In this article, we investigate the content distribution in the hotspots area, whose traffic is offloaded by the combination of the unmanned aerial vehicle (UAV) communication and edge caching. In cache-enabling UAV-assisted cellular networks, the network deployment and caching placement are vital for quality of experience (QoE) of users with content distribution applications. We formulate a joint optimization problem of UAV deployment and caching placement for maximizing QoE of users, which is evaluated by mean opinion score (MOS). To solve this challenging problem, we decompose the optimization problem into two sub-problems. Specifically, we propose a swap matching based UAV deployment algorithm, then obtain the near-optimal caching placement by greedy algorithm. Finally, we propose a low complexity iteration algorithm for the joint UAV deployment and caching placement optimization, which achieves good computational complexity-optimality tradeoff. Simulation results reveal that the proposed algorithm obtains the near-optimal solution of exhaustive search, converges within several iterations and achieves better performance compared with the benchmark algorithms.