中文摘要：

小区间动态负载均衡算法的优劣对网络性能有很大的影响，现有算法大都顾此失彼，难以保证网络关键性能指标（如呼叫阻塞率等）达到最佳。为解决这个问题，该文将负载均衡问题建模为多目标优化问题，分别对不同服务质量要求用户建模其相应目标优化函数，对有服务质量要求用户的目标函数是负载均衡指示函数和网络平均负载函数的联合优化函数，而对没有服务质量要求用户（BE用户）的目标函数是所有BE用户吞吐量的总效用函数，并将小区可用资源数和用户服务质量要求作为约束条件。另外，考虑到在实际系统中运行的计算复杂度问题，提出一种复杂度较低的分布式负载均衡算法。包括资源调度策略，用户切换条件和呼叫接入控制。仿真结果表明，该文算法可达到较好的负载均衡效果，能有效降低有服务质量要求用户的呼叫阻塞率，提高网络资源利用率。

英文摘要：

The pros and cons of load bMancing among multi cells has a big impact on the network performance. Due to the trade-off of the existing methods, they are difficult to ensure the key performance indicators （e.g. the call blocking rate） to obtain best performance in the network. In order to address the issue, Load balancing is formulated as a multi-objective optimization, of which the objective function for Quality of Service （QoS） requirement is a joint optimization function of the load balancing index and average load function of the network, and the objective function for Best Effort （BE） user is the total utility function of all the BE users＇throughput, taking the available resources and users＇ QoS requests as the constraints. Additionally, a distributed load balancing algorithm is proposed in view of the computational complexity in a practically system operation, which includes the resource scheduling policy, user switching conditions and call access control. The simulation results show that the proposed method has achieved a better load balancing index, thus effectively reducing the new call blocking rate by the QoS users and improving the network resources utilization.