A Handoff Algorithm Based on Estimated Load for Dense Green 5G Networks

Two important challenges facing 5G are energy efficiency and mobile users´ mobility in heterogeneous wireless networks (HetNets). One of the important techniques for improving energy efficiency is base station (BS)´s switching between ON and OFF modes which allows the BS to turn off some its components in lower load situations. In this paper, we address user´s seamless mobility problem and propose a handoff (HO) algorithm based on BS´s estimated load. The proposed HO algorithm based on estimated load (PHA-EL) balances load by imposing HOs from highly loaded BSs to lightly loaded BSs. When a BS is overloaded, the user´s quality of service (QoS) will degrade and therefore the PHA-EL is used to improve system throughput. The PHA-EL algorithm is combined with BSs which are able to switch between ON and OFF modes (PHA-EL/ON-OFF switching) in order to improve the energy efficiency of the system.Therefore, this algorithm achieves both energy- and spectral- efficiency. Simulation results indicate that the proposed algorithm yields better performance in terms of average number of HOs, average load per BS and average payoff per BS, compared to baseline algorithm.