【作者】 刘亮；

【导师】 孙锴；

【作者基本信息】 内蒙古大学 ， 电子与通信工程（专业学位）， 2017， 硕士

【摘要】 OFDM技术的引入使得LTE系统中,采用SC-FDMA技术的上行链路与采用OFDMA技术的下行链路都能保证小区内用户之间的正交性[1],很好的解决了小区内干扰的问题。但是宽带移动通信对频谱效率的要求使得LTE系统不适合再采用传统蜂窝网络中的小区间频率复用技术来解决小区间干扰的问题[2]。但同频组网方式又会使得小区间的同频干扰非常严重。因此小区间干扰问题是LTE系统中的重中之重。小区所承载的业务与小区间干扰的产生息息相关,不同地区的小区所承载的业务会有不同的特点。因此了解业务的种类、参数以及密度与干扰之间的关系,对控制小区间的干扰,以及网络的规划与设计都有重要的意义。本文主要对LTE系统中的小区间干扰问题进行了逐步深入的研究,从理论角度进行分析,同时利用OPNET系统级仿真平台进行系统级的仿真,并且对仿真结果进行了详细的分析与描述。首先对其干扰的成因与分类进行了讨论与分析。并通过OPNET平台搭建场景进行仿真,通过仿真数据来体现和分析干扰的影响,同时确定仿真过程中需要收集的统计数据。然后对业务承载与干扰的关系分别从业务的种类、业务的参数、业务的密度,这三个角度进行论述和仿真验证。最后对小区间干扰抑制问题进行研究,介绍和比较了几种典型的小区间干扰抑制技术,并对其中ICIC技术进行了明确的分类。并通过OPNET平台搭建了软频率复用的系统级仿真场景,来表现软频率复用带来的性能提升。更多还原

【Abstract】 With OFDM’s introduction into LTE system,both uplink of SC-FDMA and downlink of OFDMA are adopted to ensure the intra-cell orthogonality among subscribers and have successfully eliminated the intra-cell interference.Nevertheless,on one hand,the requirements of broadband mobile communication for spectrum efficiency show that,as per LTE system,it doesn’t work properly for interference control if we keep at using inter-cell frequency reuse like in traditional cellular network.On the other hand,the same frequency networking brings about more serious inter-cell same frequency interference.Therefore,in LTE system,the inter-cell interference suppression becomes the top priority.The cell bearer service,associated closely with occurrence of inter-cell interference,features differently with different location.So,understanding of category,parameter,density of bearer service and their relation with interference plays an important role in inter-cell interference control,network scheme and design.This paper is aimed at deeper study on inter-cell interference in LTE system.On the ground of accomplished theoretical analysis,we adopt OPNET simulation platform for system level simulation and make the detailed analysis and description regarding the simulation result.First,the discussion and analysis are unfolded with the causes and classification of interference,followed by the scene simulation through OPNET platform.The statistics data to collect will be confirmed along with the interference impact is being manifested and analyzed via the simulation data.Then,the relation between service bearer and interference is addressed and simulatedly tested from three perspectives of category,parameter and density concerning the relevant data service.The paper is finally closed with the study on how to suppress inter-call interference,as well as with the introduction and comparison of several typical suppression technologies,among which ICIC is explicitly classified.Moreover,this paper represents the performance improved by soft frequency reuse in way of establishing the system level simulation scene of soft frequency reuse system via OPNET platform.更多还原