中文摘要：

为了提高异构网络系统的整体性能，提出了一种基于接入选择和业务转移的动态负载均衡机制。给出了接入选择问题的优化模型，通过求解模型得到了最优接入选择方案，根据接入选择方案把接入任务均衡地分配到各个基站小区中。为了削弱热点小区突发性业务对系统负载均衡性的破坏，给出了基于基站负载率阈值的业务转移方案。仿真实验结果表明，提出的动态负载均衡方案在接入阻塞率、切换掉线率、负载均衡性、系统利用率4个指标上的表现均优于已有文献报道的方案，具有较好的应用价值。

英文摘要：

To improve the overall performance of heterogeneous network systems, a novel dynamic load balancing mecha- nism based on access selection and calls transfer was proposed. A optimization model for access selection problems was given, and the optimal scheme for access selection was obtained by means of solving the optimal model. The access calls were assigned to all base stations evenly in accordance with the optimal scheme. In order to weaken the destructiveness of sudden calls from a hot area to the system load balance, a calls transfer strategy based on the threshold of the base station load rate was given. The experimental result showed that the proposed scheme per- formed better than that reported in literature in the four indicators of access blocking rate, calls dropping rate, load balance and system utilization rate, with the advantage of good application value.