Access Delay Minimization for Scalable Videos in Cache-Enabled Multi-UAV Networks
Bin Zeng, Cheng Zhan, Yang Yang, Jingrui Liao · GLOBECOM 2022 - 2022 IEEE Global Communications Conference · 2022
Utilizing unmanned aerial vehicles (UAVs) as edge caching devices to provide scalable video services to ground users is a promising endeavor, where the caching placement should balance the trade-off between video quality and video diversity. In this paper, we investigate the scalable video coding (SVC)-based layered caching scheme in cache-enabled multi-UAV networks, where specified layers of video are cached at different UAV s. We aim to minimize the aggregate video access delay of all users, via joint design of layered caching placement and UAV deployment as well as user association to provide video services with different qualities. A mixed-integer non-convex optimization problem is formulated which is arduous to solve directly, we decomposed the original problem into two subproblems and proposed corresponding algorithms, i.e., penalty successive convex approximation (P-SCA) based user association optimization algorithm and penalty difference-of-convex (P-DC) programming based UAV deployment and layered caching placement algorithm. An efficient iterative algorithm is proposed wherein we alternatively optimize two subproblems until the algorithm converges. Simulation results show that the proposed algorithm can achieve considerable benefits compared with other benchmark schemes in terms of video access delay.