【作者】 郭丽丽；

【导师】 岳殿武；

【作者基本信息】 大连海事大学 ， 通信与信息系统， 2009， 博士

【摘要】 随着全球移动用户数量的迅速增加,以及高速率、宽带无线业务量的增长,无线业务的需求与有限的无线资源之间的矛盾日益突出。目前,无线通信系统中亟待解决的问题,即是在有限的频谱资源上传输大容量、高速率的无线数据业务,需要频谱效率极高的技术,来满足人们对信息需求的急剧增长。多输入多输出(MIMO)充分开发空间资源,利用多个天线实现多发多收,在不需要增加频谱资源和天线发送功率的情况下,可以成倍地提高信道容量和频谱效率,成为下一代无线通信系统的关键技术之一。尽管传统分层设计方法在有线网络中取得巨大的成功,但因各层相互独立,难以灵活适应无线网络的变化,无法有效利用有限频谱资源。而近年提出的跨层设计方法,因可充分利用网络各层的相关性,灵活地适应无线网络环境的动态变化,实现自适应优化配置和合理分配资源,已成为无线通信系统的研究热点。本文主要围绕着MIMO无线通信系统和跨层设计理论两方面展开深入的研究,并分别提出了基于单用户系统,多用户系统和协作传输系统的跨层设计方案。论文首先概述MIMO技术和跨层设计,阐述本文的研究背景及意义,分析MIMO无线通信系统和跨层设计及相关技术的国内外研究现状。然后,针对该领域的关键技术,从以下四个方面进行研究:1、单用户多天线系统中,研究一种闭环多天线跨层设计方案CL-MRC,并分析了反馈信道存在时延对系统性能的影响,推导了频谱效率和中断概率的闭合表达式;2、基于CL-MRC实现较复杂,研究一种单用户下多发一收的闭环跨层设计方案CL-MBF,并考虑时延情况下,对比了CL-MRC与CL-MBF的性能;3、将单用户下的两种跨层方案,引入到多用户中,结合“贪婪调度”策略,在多天线和多用户分集共同作用下,形成基于多用户的跨层方案MCL-MRC和MCL-MBF,同样在时延情况下,分析并对比了两种跨层方案的系统性能;4、在虚拟MIMO协作系统中,研究了CCL跨层方案和Seleetive-CCL跨层方案,并分别从链路是独立同分布和独立不同分布两方面,来讨论系统性能。针对以上方案和算法研究,通过MatLab进行深入的实验研究,实验结果表明了所提出CL-MRC,CL-MBF,MCL-MRC,MCL-MBF,CCL和Selective-CCL跨层方案的系统性能对比原系统有明显的改善。综上所述,本文的研究成果对于无线MIMO通信系统的性能研究领域,有一定的理论意义和应用价值。更多还原

【Abstract】 With the rapid growth in the number of mobile phone users in the whole world, and the increase in high rate and wideband wireless business volume, the contradiction between wireless communication service requirements and limited wireless resources becomes increasingly conspicuous. At present, in wireless communication system, the first problem to be solved is that high-capacity and high-rate wireless data flow transmitted in limited frequency spectrum resources, requires the key technology with higher spectral efficiency, in order to satisfy more needs from men. Multiple-input multiple-output (MIMO) takes full advantage of space resources, and becomes one of the key technologies for next generation wireless communication system. And MIMO achieves multiple-transmit multiple-receive using muti-antennas and results in that channel capcity and spectral efficiency are doubled, while not increasing frequency spectrum resources and antenna transmit power.Although achieving a great success in the wired networks, traditional layered design with independent protocol layers doesn’t adapt to variable wireless networks, and results in not making effective use of limited spectral efficiency. However, cross-layer design method proposed in recent years, utilizes the relativity among network’s protocol layers, and can adapt to dynamic variation of wireless network, obtaining adaptive optimal configure and rational resources allocation. Now, cross-layer design becomes a hot research topic for wireless communication system. In this dissertation, we study on the cross-layer design theory for MIMO wireless communication system, and cross-layer design schemes based on single-user system, multi-user system and cooperative transmission system are proposed.In this dissertation, firstly, we introduce the technology of MIMO and cross-layer design, the background and meaning of this dissertation, and analyze research situation for MIMO, cross-layer design and some related technologies. Secondly, for the key technologies of current reseach, we will open the floor for discussion from the follwing four aspects:1. In single-user multi-antenna system, a closed-loop multi-antenna cross-layer design scheme CL-MRC is proposed, analyze the impact of delayed feedback on the system performance, and derive the closed-form for the spectral efficiency and outage of probability;2. Due to complicated for CL-MRC, a simple cross-layer design scheme with only one receive antenna for single-user system, named CL-MBF is proposed, and analyse and compare the performances between CL-MRC and CL-MBF;3. Bringing two cross-layer schemes of single-user system into muti-user system, utilizing "greedy schedule" strategy, and two cross-layer schemes MCL-MRC and MCL-MBF are formed based on multi-user system with multi-antenna diversity and multi-user diversity, and then analyze and compare the performances between MCL-MRC and MCL-MBF under outdated feedback;4. In virtual MIMO cooperative system, CCL cross-layer scheme and Selective-CCL cross-layer scheme are proposed, and discuss the system performances for I.I.D and Non-I.I.D separately.For the new protocols and algorithms mentioned above, the simulation experiments are carried out based on MatLab, the experimental results confirm compared to original system, the system performance of CL-MRC, CL-MBF, MCL-MRC, MCL-MBF, CCL and Selective-CCL cross-layer scheme are all improved.In conclusion, research findings in the dissertation are of profound theoretical significance and practical application purpose for the study on the performance of wireless MIMO communication.更多还原