Robust Power Control for 5G Small Cell Networks with Sleep Strategy

In this paper, the resource scheduling and power control strategy is studied for a two-tier 5G network system, which is comprised of a central macrocell and several small cells. Because cellular deployment is ultra dense in the 5G network, a sleep strategy for small cells is proposed to reduce energy consumption caused by the cellular overlapping coverage. Specifically, the imperfect channel state information (CSI) is considered due to the complex and dynamic communication environment in practice. This work attempts to maximize the resource utilization and enhance the robustness of the power control strategy with imperfect CSI. An optimization problem with probability constraints is formulated, and the high rate requirements of 5G network users are included. A novel method is provided to convert probability constraints into deterministic ones. An iterative algorithm of power control to enhance the network efficiency is proposed further. Finally, numerical results are given to illustrate the effectiveness of the joint resource scheduling scheme.