Date Added: Dec 2011
In this paper, the authors investigate load balancing problem in 3GPP Long Term Evolution (LTE) network. Since LTE network aims to serve heterogeneous users with different Quality of Service (QoS) requirements, the influence of load imbalance is quite different. For those users with minimum rate requirements, it may result in high block probability, while for others without minimum rate requirements, the throughput of boundary users may be degraded. In this paper, they take all the differences into account and formulate the problem as a multi-objective optimization problem. Then, they analyze its complexity, and propose their solution framework, which includes QoS-guaranteed hybrid scheduling, QoS-aware handover for users with and without QoS requirements, and call admission control.