【作者】 邝月娟；

【导师】 杨贯中； 杨志新；

【作者基本信息】 湖南大学 ， 软件工程， 2010， 硕士

【摘要】 无线城域网根据是否支持移动性,可以分为固定宽带无线接入空中接口标准和移动宽带无线接入空中标准。为了减少移动终端的功率消耗,尽量减少基站空中接口的使用,移动式标准IEEE 802.16e提出了休眠模式和空闲模式。针对不同类型的业务,协议中定义了三种不同的休眠模式,每种休眠模式具有不同的休眠参数。针对第一类休眠模式,802.16e建议了一种基于二倍指数递增的休眠增长算法,但在低业务量的情况下,指数增长会使休眠间隔迅速增长,导致数据帧等待时间将过长,影响业务的服务质量。为此,在基于指数增长与线性增长等休眠间隔增长算法的研究基础上,论文在流量呈现泊松分布情况下对算法进行了改进,提出了一种基于幂函数增长的休眠算法,通过MATLAB实验验证了该算法,较之指数增长算法和线性增长算法在低业务的情况下,取得了较好的性能表现。同时通过实验说明了各个参数对性能的影响。大部分休眠模式算法及性能的研究工作中,经常假设包的到达过程服从泊松分布,但是根据大量研究与实验表明,数据包的到达过程服从自相似分布。故本论文还将根据自相似分布理论,提出了二倍指数递减的休眠算法。首先通过现有研究构建自相似流量,同时建立休眠模型,然后使用模拟仿真软件OPNET在泊松流和自相似流时分别使用二倍指数递增休眠算法和二倍指数递减休眠算法进行性能比较。通过实验发现,采用二倍指数递减的算法,在牺牲一定时延时能节约更多的能量。最后,结合三种休眠模式以及不同的算法,根据不同的业务情况,论文提出一个统一的公式总结了休眠算法。更多还原

【Abstract】 WiMAX can be divided into fixed broadband wireless access air interface standard and mobile broadband wireless access air standard based on whether it supports mobility or not. In order to reduce the MS power consumption and the number of access base station interface, IEEE 802.16e proposed the sleep mode and the idle mode. For different types of business, the protocol defines three different sleep patterns, and each mode has its own power parameters.This paper studies the first sleep mode. The protocol IEEE802.16e provides the minimum sleep interval parameter and maximum parameter by double-index-increase algorithm. But in the low-business situation, the response time would be too long, which affects the quality of service. To address this issue, based on double-index-increase and linear-growth algorithm this paper proposes Power-function growth sleep algorithm based on the traditional Poisson distribution. We tested the algorithm with the help of MATLAB. Better performances achieved compared to the double-index-increase algorithm and linear-growth algorithm in the case of low business. Experiments also show the impact various parameters have on performance.We often assume that packet arrival process follows Poisson distribution, but numerous studies and experiments show that the packet arrival process subject to self-similar distribution. Therefore, according to the distribution of self-similarity theory, this paper proposes a double-index-decrease sleep algorithm. Firstly, by theoretical analysis build model, and then use the simulation software OPNET to conduct simulation test at different flow, such as Poisson stream flow and self-similarity flow. Experimental results show that the algorithm using double-index-decrease, at the expense of a certain time delay can save much more energy. At last, papers makes a conclusion formula under different circumstances.更多还原