【作者】 陈伟；

【导师】 张建华；

【作者基本信息】 北京邮电大学 ， 信息与通信工程， 2016， 硕士

【摘要】 随着移动多媒体业务的快速发展,大数据的高速传输对现有的无线通信网络提出了严峻挑战。通过在小区中部署3维天线,将3D MIMO天线技术引入到无线中继(Relay)网络,结合3DMIMO和中继技术的优势,可以进一步提升中继系统的传输能力。但国际上对于中继系统3D信道特性的研究还有很多不足。因此,本论文围绕3D环境下的固定中继通信进行讨论,完成对中继回程链路信道建模的研究,主要工作包括三个方面:(1)中继信道3D测量数据参数相关性分析。论文基于3GPP TR36.873信道模型标准分析方法,对3D环境下的无线中继信道进行测量,提取信道建模参数,通过分析各参数之间的相关性,定性分析了散射体不同分布对中继信道相关特性的影响。测量结果表明,由于中继端移动性和天线高度的变化,中继回程链路散射体分布会有所不同,与传统的直连链路相比信道特性也有较大变化。(2)基于散射体移动的3D中继信道建模。在固定无线通信系统中,周围环境散射体的移动会对接收信号产生多普勒频谱扩展,而且通信频率越高,扩展现象越明显。根据此现象和信道测量数据的分析结果,论文提出了基于散射体移动的3D中继信道建模,并从散射体不同分布对中继链路信道多普勒功率谱的影响、散射体不同速度对中继链路信道时变性的影响以及散射体不同分布对中继链路信道空域相关性的影响进行研究验证。(3)中继链路复合衰落3D信道建模。基于空时相关性的统计建模方法,论文提出了结合多径衰落和阴影衰落的中继回程链路复合衰落3D信道仿真模型。论文从理论上推导出服从广义K分布衰落的信道相关函数,分析了不同衰落深度对时间自相关函数的影响,借助天线的功率角度谱函数推导出信道的空间相关性,并基于空时相关性信道建模方法,完成中继回程链路信道3D建模仿真。整体上,论文按照实地测量结合理论模型分析的研究路线,分析了不同散射体分布和速度对3D中继信道相关特性的影响,并利用空时相关性信道建模方法,给出了更为广泛的复合衰落中继链路3D信道建模仿真。更多还原

【Abstract】 With the rapid expansion of mobile multi-media services,high-speed transmission of large data on existing wireless communication network presents a challenge.By deploying 3-Dimensional antennas in cells and utilizing advantages of the 3D MIMO and relay technologies,people can further enhance the transmission capability of the relay systems.However,some shortcomings of the research on 3D relay channel modeling have been pointed out publicly.Thus,this thesis will focus on the relay channel propagation characteristics and modeling of fixed relay backhaul link under 3D environment based on channel measurements and theoretical analysis.The main work of this thesis includes three points:(1)The extraction and analysis of correlation characteristics of 3D relay channel from measurement data.With the methods of 3GPP TR36.873,this thesis has extracted channel model parameters and analyzed the correlation characteristics from the relay channel measurements in 3D environment.All of these are aimed to investigate the effects of different scatterers distribution and velocity on relay channel propagation.Measurement results show that there are some distinct differences,which are caused by the relay’s mobility and antenna height,between the relay backhaul link and the traditional direct link.(2)The modeling of the 3D relay channel based on moving scatterers.In fixed wireless communications,the received signals would still experience time variation because moving scatterers around the antennas bring Doppler shifts to the signals.And the higher radio communication frequency is,the more obvious this phenomenon is.According to this fact and the measurement results,this thesis has proposed a 3D model for fixed MIMO relay channel based on moving scatterers.The influence of different scatterers distribution and velocity on relay backhaul link channel correlation characteristics has also been simulated and validated.(3)The modeling of 3D relay complex fading channel.Based on the space-time correlation channel modeling method,this thesis has studied the modeling of 3D relay complex fading channel,which combines the multipath fading and shadow fading.On one hand,the channel correlation function is derived theoretically from the Generalized-K fading distribution,and the effects of different fading depth on time autocorrelation are also investigated.On the other hand,the channel spatial correlation function is obtained from the antenna power angle spectrum.In this way,this thesis has completed the modeling and simulation of the 3D relay complex fading channel.In according with the measurements and theoretical model,this thesis has studied the effects of different scatterers distribution and velocity on relay backhaul channel correlation characteristics,both qualitatively and quantitatively.And a more widely used 3D relay channel model,which is suitable for the complex fading,is also proposed in this thesis.更多还原