宽带OFDM系统支持实时分组业务的接纳控制策略

Call Admission Control for Real-Time Services in Broadband OFDM Networks

针对基于分组交换的宽带正交频分复用(OFDM)无线通信系统,提出了新的动态呼叫接纳控制策略.采用马尔可夫队列模型和维纳过程预测理论,分析了实时业务的分组等待时延与其接纳概率的关系.并利用此关系,得到了以分组等待时延和切换中断概率为约束条件的最大接纳概率.该策略满足系统实时业务用户连接层面和分组层面服务质量的同时达到系统带宽资源的最大化利用.仿真结果验证了所提策略的性能.

A new admission control scheme was presented in packet-switched orthogonal frequency division multiplexing （OFDM） wireless communications. In the scheme, the relationship between the packet waiting time in queue and the acceptance ratios for real-time services was derived with Markovian queueing model and Wiener prediction theory. Thereafter, the maximum acceptance ratios subject to a hard constraint on packet waiting time and handoff call dropping probability was obtained. The proposed scheme will satisfy the packet-level and call-level quality-of-service （QoS） requirements for real-time services while maintaining high bandwidth utilization. Simulation results verify the effective- ness of the proposed scheme.