Cooperative Load Balancing in OFDMA Small Cell Networks

Abstract

This paper aims at balancing the load of OFDMA small cell networks. Different with the existing works that define the load as the number of service user equipments or the occupied amount of resources, we model the load as the service ability of small cells. The system load balancing problem that adopts the max-min fairness measure is formulated as a lexicographical minimization problem whose solution is NP-hard. To reduce the complexity and obtain a satisfying performance, a sub-optimal solution named as cooperative load balancing scheme (CLBS) is proposed. By sequentially conducting the cooperative user association, cooperative scheduling operation and cooperative transmission power optimization in CLBS, the system load is balanced to a stable state in a lexicographical non-increasing manner. Simulations results show that CLBS guarantees a satisfying load balancing performance in small cell networks.