高速铁路场景MIMO信道建模研究

发布时间：2018-04-09 09:06

本文选题：轨道交通　切入点：电波传播与建模　出处：《北京交通大学》2015年博士论文

【摘要】：经过10多年的发展,中国已经建成了世界上最长里程的高速铁路网,同时具有自主知识产权的中国高铁技术正在日益成熟,高铁已经成为中国轨道交通崛起的名片和代名词。保障安全是高速铁路运行中的重中之重,而这要以列车的状态信息和控制信息及时地传输和交互为基础,因此负责高铁信息传输的无线通信系统的性能就显得尤为重要。与此同时,随着高铁线路覆盖的日益完善,人们选择高铁出行的常态化,面向旅客的信息化服务也将提上日程。这些新业务对高铁无线通信系统提出了更高的要求,其不但能够保证列控信息准确、可靠地传输,更需要向旅客提供高速的数据通信服务。因此在新的趋势下,需要使用新的无线通信技术。MIMO (Multiple-Input Multiple-Output)是4G LTE (Long Term Evolution)通信系统的主要物理层技术,可以为系统提供分集与复用增益。因此将MIMO技术应用到高铁通信中,可以降低传输的误码率,同时提高信道容量。MIMO系统的性能会受到电波传播环境和信道的影响,而高铁这一特殊场景所呈现出的不同电波传播特性,使得之前的MIMO信道模型无法直接应用在高速铁路上。同时目前针对高速铁路信道的研究,尤其是影响MIMO性能的信道空间和角度特性的研究还很少。本文在现有高速铁路窄带单天线测试数据和其特殊场景分析的基础上,首先分析高铁信道的时变非平稳特性,之后利用半确定MIMO信道建模方法对高速铁路场景进行信道建模,并分析信道的空间相关性,同时考虑天线阵列的结构对MIMO信道容量的影响,为高铁MIMO无线通信系统的设计和仿真提供依据。本文的主要工作如下：1)针对列车的高速移动性,利用郑西高铁客运专线的窄带信道测试数据,采用信号幅度相关性定义的信道平稳区间,研究不同列车速度、不同场景下的信道平稳区间长度统计特性,并将这一结果与五种标准MIMO信道模型的平稳区间统计特性作对比,这一对比结果可以指导高速铁路场景下无线通信系统的仿真与设计。2)基于高速铁路场景的调研和信道测试,选取了其中的高架桥与路堑场景进行分析,对于这两种高铁特色场景使用MIMO半确定性信道建模方法,提出了针对高架桥场景的规则球形MIMO信道模型,同时根据高铁路堑场景的结构特点,提出基于路堑结构的散射体MIMO信道模型。模型中的大尺度参数基于郑西高铁的测试数据,小尺度信道参数基于散射体簇的分析,最后利用模型得到这两种场景下的空间相关特性。3)针对高速铁路场景的小区覆盖特点,使用包含多种天线参数的模型,研究多种天线结构对MIMO信道容量的影响。并针对其中的线性阵列,给出其中使信道容量最优的方向角度。4)针对目前高速铁路多天线信道测试所面临的困难和限制条件,研究多种MIMO信道测试方案在铁路上的适用性,并根据高速铁路场景的特点,综合了单天线虚拟测试和切换开关MIMO测试的原理,提出了适用于高速铁路场景的移动虚拟MIMO测试方案,并给出了单根虚拟天线可以等效天线阵个数的条件,通过搭建1×3 SIMO (Single-Input Multiple-Output)信道测试平台以及实际的测试验证了这一方案的可行性。
[Abstract]:After 10 years of development, China has built the world's longest mileage of high-speed railway network, and has independent intellectual property rights China high iron technology is increasingly mature, high-speed rail has become China rail transit and the rise of the name card synonymous. Safety is the priority among priorities of high-speed railway transport line, and this to be based on the state information and control information of train timely transmission and interaction, so the performance of wireless communication system for high-speed transmission of information is particularly important. At the same time, along with the high-speed rail line coverage has improved, people choose the normalization of high-speed rail travel, information service for travelers will also be put on the agenda the new business has put forward higher requirements for high speed wireless communication system, which can not only ensure the train control information is accurate, reliable transmission, to provide high-speed data communication services to passengers. So in the new trend, need to use the new wireless communication technology.MIMO (Multiple-Input Multiple-Output) 4G LTE (Long Term Evolution) communication system physical layer technology, can provide diversity and multiplexing gain for the system. So MIMO technology will be applied to the high-speed communication, can reduce the bit error rate, and improve the the performance of the channel capacity of.MIMO system will be affected by the electromagnetic wave propagation environment and channel, and different propagation characteristics of this special scene showing a high iron, the MIMO channel model can not be used directly before in high speed railway. At the same time for the high-speed railway channel research, especially the influence of channel space performance MIMO the characteristics and angle are rare. The paper analyses the existing high-speed railway narrowband single antenna test data and the special scene on the first channel of high speed railway The non-stationary and time-varying characteristics, using semi deterministic MIMO channel modeling method for channel modeling of high-speed railway scene, and analyze the spatial correlation of the channel, considering the impact of the structure of the antenna array on the MIMO channel capacity, for the design and Simulation of high-speed MIMO wireless communication system is to provide the basis. The main works of this paper are as follows: 1 for high speed trains) mobility, using the narrowband channel test data of Zhengzhou-Xi'an high-speed rail passenger line, smooth channel interval by signal amplitude correlation definition, study the different train speed, Xin Daoping stable interval length statistical characteristics under different scenarios, and the stable interval of the statistic results and five standard MIMO channel model for contrast, the contrast results can be.2 simulation and design of wireless communication system under the guidance of high-speed railway scene investigation) and channel of high-speed railway scene test based on Selection Take the viaduct and cut the scene analysis, for the two kinds of characteristics of high iron scene using MIMO semi deterministic channel modeling method, puts forward the rule of spherical MIMO channel model for viaduct scene, at the same time according to the structural characteristics of high railway cut scenes, put forward scattering MIMO channel model based on the structure of large scale cutting. The parameters in the model test data of Zhengzhou-Xi'an high-speed rail based on small scale channel parameter analysis of scatterers based on clusters, and finally get the two scenarios of the spatial correlation characteristics using.3 model) based on high-speed railway scene of small area coverage characteristics, use contain a variety of antenna parameters model, research the influence of antenna structure on MIMO channel capacity. According to the linear array, which gives the channel capacity optimal direction angle.4) aiming at the high-speed railway multi antenna channel test difficulty Constraints and applicability of various MIMO channel test scheme on the railway, and according to the characteristics of high-speed railway scene, the principle of single antenna switch virtual test and MIMO test, the MIMO test scheme for mobile virtual high-speed railway scene, and gives a virtual antenna array can be equivalent to a the number of conditions, by building a 1 x 3 SIMO (Single-Input Multiple-Output) channel test platform and the actual test to verify the feasibility of this scheme.

【学位授予单位】：北京交通大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：U285

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