Jointly Optimized Cache Control and Energy Efficiency for Downlink Cellular Networks

In this paper, we propose an optimal scheme for solving the joint cache control and energy efficiency optimization problem for the downlink transmission in a backhaul cellular network. The first short-term subproblem is aimed at finding the optimal beamforming matrices at the hub and BSs to maximize the energy efficiency for the scenario where the network operates in the non-caching mode. The second short-term subproblem is aimed at solving the optimal beamforming matrices at the base stations (BSs) to maximize the energy efficiency for the scenario where the network operates in the caching mode. On the other hand, the goal of the long-term subproblem is to maximize the long-term energy efficiency of the examined network. Finally, numerical results show that the proposed cache control and energy efficiency optimization scheme provides significant performance improvement over the conventional non-caching schemes.