On enhancing energy efficiency via elastic cell-zooming algorithm in three-tier heterogeneous wireless networks

Abstract

The explosive growth of mobile users has brought great challenges to traditional cellular networks. The deployment of various Small-cell Base Stations (SBSs) provides a flexible way to address the problem of covering blind spots in Macro-cell Base Station (MBS) and reduce the traffic loads from MBS. In this paper, we investigate energy-saving based on various densities of SBSs including picocells and femtocells in multi-tier heterogeneous networks. We propose an elastic cell-zooming algorithm (ECZA) in order to solve the problem of power consumption and traffic loads in the three-tier heterogeneous cellular networks. Besides, to solve the SBSs zooming problem, which is a NP hard problem, we devise the greedy algorithm to find the suboptimal solution. Simulation results show that the proposed scheme can effectively improve the energy efficiency under the constraint of the outage probability of mobile users in the multi-tier HetNets.