【作者】 李仁波；

【导师】 张春业；

【作者基本信息】 山东大学 ， 通信与信息系统， 2011， 硕士

【摘要】 人们惊奇于WiMAX技术的迅猛崛起时,3GPP也开始了UMTS技术长期演进(Long Term Evolution,3GPP LTE)的研究。中国移动表示2011年将是TD-LTE商用的元年,一些人据此认为4G业务很快就能丌展,其实并非这样。移动通信领域普遍认为3GPP LTE项目其实属于3G的长期演进。3GPP LTE并不是人们心目中所想的4G技术,它只是3G与4G技术之间的一个过渡,是3.9G的全球标准,其采用OFDM和MIMO技术作为其无线网络演进的唯一标准,改进进而增强3G的空中接入技术。3GPP LTE还属于3G的标准范畴内,只不过比较接近4G,而3GPP LTE-Advanced才是4G。3GPP LTE提高了小区容量,降低了系统延迟,改善了小区边缘用户的性能。在20MHz频谱带宽下能够提供下行326Mbit/s与上行86Mbit/s的峰值速率。针对3GPP LTE标准的发展,3GPP制定了明确的时间表。整个标准发展过程分为两个阶段：研究项目阶段和工作项目阶段。前一个阶段主要完成对目标需求的定义,以及对3GPP LTE的概念的明确等；紧接着征集候选技术提案,并对技术提案进行评估,确定其是否符合目标需求。2006年中期,研究项目阶段结束。工作项目阶段在2006年中期以前建立,并丌始3GPP LTE标准的建立。该阶段会对未来3GPP LTE标准的细节展开讨论和研究,这个过程同以前3G标准在3GPP中的制定过程是一样的,持续到2007年中期。整个过程相比3G标准的制定节奏明显加快,主要是因为考虑到市场的需求。宽带技术不断创新,与此同时,3GPP也将在最短的时间内推出最新的技术。这给运营业带来了新的机遇,更新更快、甚至完全可以和有线网络相媲美的无线通信业务可以在不远的将来得以实现。在这样的研究大背景下,3GPP LTE中的关键技术,比如物理层下行链路中OFDM技术以及切换机制也受到了越来越多研究者的关注,成为3GPP LTE技术的研究热点。基于上述背景知识,本文学习和研究了3GPP LTE相关知识,诸如3GPP LTE网络构架、系统性能需求、协议构架和核心技术。理解3GPP LTE物理层基本概念,掌握物理层链路相关知识。学习和研究3GPP LTE物理层下行链路中的关键技术之一：正交频分多址技术。对如何抑制OFDM系统高PAPR做出研究。然后论文提出了一种基于合数子块序列优化的OFDM-PTS算法。与传统的各种PTS算法相比,采用该算法后,OFDM系统的计算复杂度适度降低,峰均功率比的抑制性能得到动态改善,获得很好的折中效果,可以更好地满足工程应用。最后学习和研究3GPP LTE物理层下行链路中另一项关键技术：切换技术。研究切换流程、切换分类,提出并设计了针对同频、异频和异系统情况下的切换算法,得出了不同参数设置下的切换基本性能,由于实际应用中网络环境是多变的,参数设置也会随之改变,本文研究了参数CIO对切换成功率以及乒乓效应的影响。更多还原

【Abstract】 Just as people were surprised about the rapid rise of WiMAX technology,3GPP has started the long-term evolution of UMTS technology (Long Term Evolution, LTE).China Mobile indicates that 2011 will be the first year of commercial TD-LTE, some people think that 4G will be able to conduct business quickly, in fact not the case.3GPP LTE project is just a long-term evolution of 3G. 3GPP LTE is not the mind of the 4G, that is only a transition between 3G and 4G technologies.LTE is the global standard for 3.9G, which uses OFDM and MIMO technologies as the sole criterion for the evolution of wireless networks to improve further enhanced 3G air access technology,3GPP LTE is also within the context of 3G standard, but closer to 4G, but 3GPP LTE-Advanced is a 4G technology.3GPP LTE can increase cell capacity, reduce system latency and improve the performance of the cell edge users. In 20MHz spectrum bandwidth it can provide peak rate in downlink: 326Mbit/s and in uplink: 86Mbit/s.For the development of 3 GPP LTE standard,3GPP establishes a clear timetable. The standard development process is divided into two stages:research stage and work stage. The first stage finishes the definition of target requirements, as well as the definitude concept of 3GPP LTE, etc. Then collects candidate technical proposals, and evaluates technical proposals to determine whether they can meet the target demand. The end of the first stage is in mid of 2006.Work stage of the project established in mid of 2006 and began the establishment of 3GPP LTE standards. Work stage would be to discuss and study the details of this standard until the middle of 2007. Compared to the 3G standards, LTE standard was in an accelerated pace, mainly because of the market demand. At the same time of the broadband technology innovation,3GPP will launch the latest technology in the shortest time. This brings new opportunities for operators, faster wireless communications services can be realized in the nearly future.In the context of this study, key technologies of 3GPP LTE, such as OFDM technology and handoff mechanism has also been the concern of more and more researchers,3GPP LTE technology will be a research hotspot.Based on the above, this paper studies and researches the related knowledges of 3GPP LTE, such as 3GPP LTE network architecture, system performance requirements, protocol architecture and core technologies.This paper proposes an OFDM-PTS algorithm based on optimisation of composite number sub-block sequences. Compared with the traditional algorithm, this algorithm can reduce the computational complexity and suppress the papr dynamically, then reach a good compromise results that can better meet the engineering application.Finally, this paper studies the handoff technology in 3GPP LTE physical layer downlink. Study the handoff process and handoff classification,then propose and design the handoff algorithm under the situation of same frequency, different frequency and different systems, we can obtaine basic performance under different parameter settings. The network environment is changing, the parameter settings will also change, In this paper, we study the influence of CIO about the success rate and the the ping-pong effect.更多还原