Robust and Secure Content Delivery in Energy and Spectrum Efficient Next-Generation Networks

The four promising technologies, namely multiuser sparse code multiple access, content caching, energy harvesting, and physical layer security, are addressed in this paper for efficient resource allocation in the access and backhaul links of a wireless network. In order to jointly consider these technologies in a unified framework, we optimize the energy efficiency of the access links under system constraints. Due to non-convexity of the optimization problems, we propose an iterative algorithm based on the alternative and successive convex approximation method. The simulation results show that the proposed caching scheme outperforms the existing traditional caching schemes like random caching and most popular caching. Moreover, the proposed joint access and backhaul optimization has better performance than the disjoint one.