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近年来,随着个人数据通信的发展,以及便携式数据终端、多媒体终端的广泛应用,为了使人们在地球的任意角落进行无线宽带接入Internet,随时随地随意使用各种数字设备和可视通信.要求传统的计算机网络由有线向无线,由固定向移动,由单一业务向多媒体业务发展,因此需要更大的无线接入带宽.无线宽带接入具有安装迅速、不受现有管道限制、费用几乎与距离无关的优点.该文通过对无线宽带接入技术的比较,无线局域网IEEE802.11标准序列拥有较高的带宽/成本比,是较理想的无线宽带接入技术.当无线局域网作为音频、视频等不同QoS要求的数据业务接入手段时,对无线局域网的性能就有更高的要求,而介质接入控制协议是决定网络性能的关键.因此,对无线局域网的接入控制协议进行研究,并对其控制机制进行改进,从而达到改善网络的性能,具有重要意义.该论文基于视频等实时业务QoS控制特性,在以往研究的基础上,采用嵌入Markov链和概率母函数的分析方法,建立了一个新的具有优先级控制的两级循环查询服务的控制传输模型.论文第一章重点介绍了无线宽带接入网的发展、类型及应用前景.介绍了几种主要的发展较快的无线宽带接入技术,进一步对几种技术进行比较,得知无线局域网是较理想的无线宽带接入技术.论文第二章对无线局域网的MAC协议进行了研究,重点分析了无竞争方式的点协调功能PCF,对其周期查询控制方式作了进一步分析,为后面对周期查询系统改进,从而改善网络性能奠定基础.研究分析了H.323多媒体传输协议及应用,进一步得出无线视频传输需要解决的问题.论文的第三章首先对周期查询排队服务系统的研究进展作了介绍.采用嵌入Markov链和概率母函数的方法,用完全服务规则和门限服务规则构造出两级循环查询多业务优先级控制传输系统的数学模型,并对系统性能进行了分析,给出系统的一阶和二阶特性,并进一步给出了高优先级业务和低优先级业务的平均排队队长和平均时延的精确解析式.然后对系统进行理论计算,并通过计算机仿真进行验证.通过计算结果和系统性能的曲线图,对系统进行了讨论分析和评价.论文第四章,在具体分析无线局域网的视频业务、语音业务等数据传输业务的基础上,通过两级循环查询多业务优先级控制传输系统的实际应用,并与文献[23]的周期查询限定服务(K=1)系统及周期查询限定服务(K=1)并行调度控制系统进行比较,进一步验证了新系统对无线宽带视频等实时业务传输性能的改进.论文第五章总结了全文的研究工作,同时分析了课题需要进一步解决的问题,对今后的研究工作进行了展望.Abstract In the recent years, with the development of personal digital communication and the wide spread of portable digital terminal and multimedia terminal, in order to let people make use of all kinds of digital instruments and visible communication, get internet using wireless broad band anywhere, anytime. It is required traditional computer network alter from lineate to wireless, from immovable to mobile, from single operation to multimedia operation, therefore a more wider wireless band width is needed. Wireless broadband access have advantages of rapid installation, limitless of pipeline and fee independent of distance. In this paper, we compare all kinds of wireless access technique. Comparison shows IEEE802.11 standard serials possess of higher bandwidth and cost ratio, which is perfect technique of wireless access. When wireless LAN serve as data access means of QoS request like audio-data and video-data, it has more requirement for performance of wireless LAN. MAC protocol is the key to network performance, thus research on access protocol of wireless LAN and improving on its control system for better performance are quite useful. In this paper, based on QoS controlling characteristics of video operation, we use analysis methods of embedded Markov chain and probability generating function to construct a new controlling transform model which has priority level control and two orders circular query service.In the first chapter, we introduce the development, type and application foreground of wireless broadband access network. We explain several kinds of fast developing wireless access techniques and compare them. With comparison results,we know wireless LAN is better wireless broadband access technique.In the second chapter, we study on the MAC protocols of wireless LAN, analyze contention free PCF point coordination function, and analyze controlling type of circular query. These works are basis of improving circular query system, therefore basis of improving network performance. Through working over multimedia transform protocol H.323 and its application, we get the problems in wireless video-data transform. In the third chapter, we introduce the development of polling system. We construct two order circulate query mathematic model, adopting embedded Markov chain and probability generating function, using exhaustive service rule and gatedservice rule. We analyze system performance and present first order and second ordercharacteristic. Further more, we present the precise equation of average queuing length and average delay for high-level PRI and low-level order PRI operation. We make use of computer emulating to validate theoretic results. With these results and diagram of system performance, we discuss and estimate the whole system. In the fourth chapter, based on analyzing results of video-operation and audio-operation for wireless LAN, we compare the methods of this paper and paper [23] which is about polling limited service system (K=1) and pollinglimited parallel control service system (K=1). With comparison, we validate the improvement of new system in transform performance of video-operation and other real time operation. At last, we summarize the whole research work, and then discuss the problems that should be resolved, prospect the future research.