【作者】 李博光；

【导师】 金顺福；

【作者基本信息】 燕山大学 ， 计算机应用技术， 2010， 硕士

【摘要】 IEEE802.16e是下一代移动无线宽带城域网的最新标准,支持用户节点以车辆速度移动。为了提高移动终端的能量效率,IEEE802.16e提出三种休眠模式,其中,节能类型I用于尽力而为BE业务及非实时可变速率NRT-VR业务。本文对节能类型I进行休眠策略研究及性能分析。首先,基于节能类型I的基本休眠策略,分别考虑无后效业务与自相似业务,建立休假长度指数变化的Geom/G/1及Geomξ/G/1排队模型,给出能量节省率,能量消耗率,系统切换率和数据帧平均响应时间等性能指标的表达式。结合数值例子与系统仿真,定量分析休眠窗口大小对系统性能的影响。其次,综合考虑能量节省率,能量消耗率,系统切换率和数据帧平均响应时间等系统性能指标,构造成本函数,给出休眠窗口的优化设置方案。基于休眠状态与唤醒状态之间的切换过程,给出休眠策略的启动阈值。然后,在基本的节能类型I中,提出一种休眠延迟策略。平行于基本休眠策略,建立带有休假延迟且休假长度指数变化的Geom/G/1及Geomξ/G/1排队模型,并给出相关性能指标的表达式。通过数值例子与系统仿真,定量分析休眠延迟定时器对系统性能的影响,并验证休眠延迟策略有效性。最后,针对带有休眠延迟的节能类型I,考虑能量节省率和数据帧平均响应时间的折衷问题,构造成本函数,给出休眠延迟定时器大小的优化设置方案。更多还原

【Abstract】 IEEE802.16e is one of the latest standards for the next generation wireless broadband metropolitan network, in which user nodes can move at vehicle speed. In order to improve the energy efficiency for the mobile station, IEEE802.16e offers three kinds of sleep mode. Power saving class I is used for the best effect and the no real time variable rate services. We study the policy and performance analysis for power saving class I in this paper.Firstly, based on the operation mechanism of the elementary power saving class I, take into account the memoryless traffic and the self-similar traffic respectively, a Geom/G/1 and a Geomξ/G/1 multiple queueing models with exponential vacation are built. The expressions of the power saving ratio, the power consuming ratio, the system handover ratio and the average response time are presented. With the numerical results and simulation experiments, the influence of the sleep window length on the system performance measures is demonstrated.Secondly, considering both the power saving ratio and the average response time, a cost model is developed to determine the optimum length of the sleep window. Based on the handover process between the sleep state and the awake state, an optimal threshold for starting the sleep mode is given.Thirdly, a strategy called sleep-delay is provided on the elementary power saving class I. A Geom/G/1 and a Geomξ/G/1 multiple queueing models with exponential vacation and sleep-delay are built to describe the working principle of the power saving class I with sleep-delay. Correspondingly, the expressions of the system performance measures are presented. The dependency relationships of system performance measures on the sleep-delay timer length are discussed by numerical results and simulation experiments, and the validity of sleep-delay strategy is verified.Finally, considering the tradeoff between the energy saving ratio and the average response time for the power saving class I with sleep-delay, a cost model is developed to give the optimal sleep-delay timer length.更多还原