Coverage and Capacity Optimization in Heterogeneous Networks (HetNets): A Green Approach

This paper considers a coverage and capacity optimization problem in heterogeneous networks (HetNets), where small cells are deployed within the area of a macro base station. The small cells are configured to the optimal power level in order to maximize the users' throughput without causing interference to the other users and simultaneously taking into account the network's energy consumption by switching off redundant small cells. The problem is formulated and solved in terms of a complex optimization problem through the IBM ILOG CPLEX Optimization Studio. Two cases are studied, firstly by taking into account only network performance (PRF case) and then with the introduction of green aspects (EE case). The evaluation proves that the power consumption is reduced by 33 % in the energy efficient case, while the average user throughput is reduced by 18 %.