A user-centric load balance scheme for small cell networks

With the dramatic increase of mobile data traffic in the foreseeable future, small cells are set to play an important role in expanding the target capacity of wireless networks. At the same time, to balance the load among all the small cell base stations (SBSs) becomes more and more important. We consider this problem in a user-centric way, where users are able to make decision to choose their SBSs for service. We use congestion penalty and switch penalty to help users make the decision. We give sufficient conditions to guarantee the convergence of the load in each cell. It is proved that the choice of each user will converge to an equilibrium point as well. To analyze the load in a single small cell, we introduce the concept of equivalent cell. Moreover, a second order differential equation is formulated to describe the load fluctuation of a single small cell. Convergence rate is analyzed and it can be controlled by the proposed two penalties. Finally, simulation results validate the proposed scheme.