【作者】 郭欣；

【导师】 侯紫峰；

【作者基本信息】 中国科学技术大学 ， 计算机系统结构， 2008， 博士

【摘要】 无线多跳中继网络作为一种新兴网络架构,能够有效扩大宽带无线网络小区覆盖面积,提高链路质量,屏蔽位置和移动速度等条件影响为用户提供公平的高质量无线多媒体服务。然而,数据的多次转发引发了严重的系统容量问题。本文研究了中继网络结构特性与系统容量之间的联系,给出提高资源利用率的中继网络QoS架构,对其核心内容资源调度和准入控制问题的数学建模、算法设计和性能分析进行了全面研究。具体研究成果包括:首先,分析了两跳中继网络的结构及影响系统性能的因素,提出了保证用户QoS需求,随网络拓扑和干扰状况变化动态调整的自适应资源复用调度算法ARRS。为进一步研究中继网络结构与系统容量的量化关系奠定了基础。其次,深入分析一般化多跳中继网络结构,通过将图论染色理论扩展到加权混合图的多重染色WMMC问题,建立起中继网络结构特性与系统容量之间的联系。对WMMC问题进行了形式化定义、分类和加权色数定界的全面研究。建立起最小化调度时间为目标的中继网络调度问题和以求解加权色数为目标的WMMC问题的映射。以此为依据,设计了高效的多跳中继网络资源调度算法,并对算法性能进行了理论分析。最后,研究了中继网络准入控制问题,指出系统吞吐量与业务带宽需求的非线性关系造成中继网络和传统单跳网络准入控制的根本区别。建立了以资源调度为基础,结合中继选择的中继网络准入控制策略。设计了动态资源预留准入控制算法DBRAC,确保中继网络满足多媒体业务QoS需求的同时,有效的降低切换业务的阻塞率,并且提高了系统资源的利用率。构造了中继网络业务流模型,为准入控制策略性能分析提供理论基础。更多还原

【Abstract】 As a promising network architecture, wireless multihop relay network can efficiently enhance the coverage area of broadband wireless access network, improve the transmission links quality and provide fair high quality multimedia services for mobile users ignoring their locations and speeds. However, the relaying of duplicated user data between base station and relay stations leads to serious capacity degradation. In this paper, we study the connection between relay network structure and the system capacity, construct relay network QoS architecture to improve the resource utilization, and study the modeling, algorithm design and performance analysis for resource scheduling and admission control. The contributions of our work are as follows:Firstly, we analyze two-hop relay network structure characteristics, based on which we propose an adaptive resource reuse scheduling (ARRS) algorithm with the goal of enhancing the system capacity for relay network, which supports arbitrary topology and relay stations mobility.Secondly, we analyze general multihop relay network architecture and establish the connection between relay network scheduling and graph coloring by extending the coloring problem to the direction of weighted mixed graph multicoloring (WMMC). We formulate formal definitions and classifications for WMMC and study the bounds on the weighted chromatic numbers. Thus, a relay network scheduling problem to minimize the completion time is mapped into WMMC with the object of obtaining the weighted chromatic numbers. Based on the mathematical model, we design high efficient scheduling algorithms and propose the performance analysis.Finally, we study the relay network admission control and point out that the nonlinear relation between system throughput and traffic connection bandwidth request tells the admission control for relay network from that for single-hop cellular network. We establish relay network admission control mechanism based on both resource scheduling and relay selection. We design dynamic bandwidth reservation admission control (DBRAC) algorithm to satisfy the QoS requirements of all services and decrease blocking probability for handoff traffics while improving the resource utilization of the system. And we develop relay network traffic flow model for analyzing the performance of admission control algorithms.更多还原