【作者】 高强；

【导师】 俞重远；

【作者基本信息】 北京邮电大学 ， 电子与通信工程（专业学位）， 2013， 硕士

【摘要】 随着用户对通信业务需求的不断提高和WiMAX技术的迅猛发展,3GPP (The3rd Generation Partnership Project)为了应对挑战开始了对LTE (Long Term Evolution)技术的研究。LTE-A技术是在LTE技术的基础上针对网络中的突出问题进行更进一步的研究。在演进的过程中为了满足了网络的系统容量、用户吞吐量等需求,提出了多点协作、异构网、载波聚合以及中继等多项技术。异构网技术在网络中引入了新的低功率小区,很好的解决了热点覆盖问题；多点协作技术通过基站间的协作提高了系统性能,尤其是小区边缘的服务质量,这些技术都是当今移动通信研究的热点。本文介绍了LTE-A技术中异构网和多点协作技术,主要包括：(1)根据协议规定和理论研究搭建仿真平台,详细介绍仿真平台中的测量规则、事件触发、切换、调度等算法。本文对两种调度算法做重点介绍,分别是轮询调度算法和正比公平调度算法。组成系统平台的主要部分有：网络的拓扑模块、移动性模块、测量模块、反馈和调度模块。主要算法和重点模块构成了仿真平台的核心,保证了数据的准确性。(2)异构网系统中,由于低功率节点引入改变了原来的基站分布对系统性能造成影响,体现在信道干扰的计算、小区间切换和系统资源分配。低功率节点的引入增加了系统的干扰源也提高了系统的复杂度。干扰的增加使切换失败率提高,通过干扰协调方案来解决此问题。针对资源分配不均的问题提出了负载均衡算法,综合考虑小区的负载和用户服务质量实现资源的均衡分配,提高系统的整体性能。(3)多点协作系统中每个用户可以有多个服务小区,在进行切换判决时有多种方案。为了找到最佳的切换方案,在切换时需要综合考虑多点协作集合中小区的信息。本文对三种不同判决条件下的切换进行仿真,通过对切换总数、乒乓切换数和系统吞吐量的结果分析,通过对比最后选出一种切换数较少同时系统吞吐量较高的最优方案。更多还原

【Abstract】 Along with the high user demand of communication service and WiMAX technology develop rapidly. In order to meet this challenges,3GPP began the research of LTE. LTE-A is the further evolution of LTE. In the course of evolution, LTE-A introduced CoMP(Coordinated Multi-point Transmission and Reception), Het-Net (Heterogeneous Network), CA (Carrier Aggregation) and Relay as feature, which can meet the demand of system capacity and user throughput. Het-Net solved the problem of hot point overlap after include low-power node. CoMP improve the system performance via the coordinate of several node, especially the service quality in the cell edge. Nowadays, this technologies has became the hotspot of mobile communication research.This paper emphasizes Het-Net and CoMP technology of LTE-A. The main contributions are as follows:Construct the LTE-A system level platform depend on protocol and theoretical research. Introducing the algorithms such as measurement rules, event trigger, handover and scheduling. Round Robin and Proportional Fair algorithms are emphasized in the scheduling module. The main algorithms and important modules construct the core of the platform, it ensure correctness of the data.In heterogeneous network system, the station distribution changed after the introduction of low-power node. This changes affect the count of channel interference, handover and resource allocation. The interference between cells and complexity are improved after the introduction of low-power node. The interference caused high handover failure rate, it can be solved by interference coordination solution. To solve the problem of uneven resource allocation, this thesis put forward a load balance method. This method improve the system performance depend on the load of cells and service quality.In CoMP system, there are several schemes of handover trigger event because every user is serviced by coordinated multi-point. In order to find the best scheme, all information can be use in the coordinated group during the handover. This thesis simulated three scheme under the different handover trigger events. According to analyse simulation results of handover, Ping:Pang handover and throughput to identify the best scheme.更多还原