The Optimal Placement for Caching UAV-assisted Mobile Relay Communication

Recently, unmanned aerial vehicles (UAVs)-assisted communication networks have been widely concerned in terrestrial and maritime communications for UAV high mobility. However, capacity-limited wireless backhaul links connected UAVs with the base stations degrade the transmission rate of the links from UAVs to the ground users. In this paper, we focus on a half-duplex decode-and-forward cache-enabled UAV relaying communication system in downlink scenario and obtain a semi closed-form of the optimal UAV placement by maximizing the system average achievable rate. Numerical results validate the accuracy of our theoretical analysis and show the significant effects of caching on optimal UAV placement and the system average achievable rate.