三维空间链路的信道建模及其车载应用分析

发布时间：2018-05-05 15:28

本文选题：信道建模 + 多输入多输出　；参考：《南京信息工程大学》2017年硕士论文

【摘要】：随着智能移动终端的快速普及,无线通信用户的数量不断增多,人们对数据传输速率的需求呈指数增长。而宽带系统的发展、数据速率的提高及各项服务的需求,使得信道建模成为一个研究热点。本文主要围绕基于三维(Three Dimensional, 3D)空间链路的信道建模及其车载应用进行分析,通过宏蜂窝3D空间域的信道建模,深入分析多输入多输出(Multiple Input Multiple Output,MIMO)天线阵列、多普勒频移(Doppler Shift, DS)、功率谱密度(Power Spectral Density,PSD)、空间衰落相关性(Spatial Fading Correlation, SFC)、信道容量等影响系统性能的各方面因素,为无线移动通信系统的性能分析提供理论基础。本文的研究工作主要分为以下四个方面:首先,针对室外宏小区(Macrocell)移动通信环境下的多径衰落问题,引入垂直分量进而建立三维空间域的统计信道模型,提高了信道变化描述的准确性。模型推导了在方位角、仰角平面的到达角度(Angle of Arrival, AOA)以及到达时延(Time of Arrival, TOA)概率密度函数的分析算法,给出电磁信号分别在移动台(Mobile Station, MS)以及基站(Base Station, BS)端的空时概率密度闭合理论式,深入分析影响空时特性的相关因素,为多径信号在垂直维度的参数估计提供理论支持。其次,基于上述模型,将其MS附近的散射体衰减至二维平面内,构建一个基于散射簇的三维统计信道模型。数值推导多径衰落信道正向、反向链路的概率密度分布,包括到达角度、到达时延等;分析频率变化引起的正向、反向信道链路多普勒频移;数值仿真结果对比分析表明,所提出模型的信道参数估计符合理论及实际的通信环境,更全面地描述了多径衰落信道的相关特性。然后,基于上述构建的3D散射簇信道模型,在设置MIMO多天线的均匀线性阵列(Uniform Linear Array, ULA)和圆形阵列(Uniform Circular Array, UCA)基础上,研究衰落信道的空时分布特性,深入分析波达信号不同方位角分布对散射信道中MIMO性能的影响,包括MIMO空间相关性、信道容量以及天线阵列配置。最后,针对室外无线信道视距(Line of Sight,LOS)/非视距(Non-Line of Sight,NLOS)传输环境下的车到车(Car-to-Car,C2C)通信,构建一种基于标准街道散射的新型统计性车载通信模型,其移动发送端(Mobile Transmitter, MT)与移动接收端(Mobile Receiver, MR)均处于移动状态。数值推导到达角、发射角(Angle of Departure, AOD)以及多普勒PSD等的函数解析式;引入参考信道模型的多普勒参量并进行对比分析,证实模型的合理性与可行性;采用控制变量法研究影响多普勒PSD、时间自相关函数(Autocorrelation Function, ACF)的相关因素。结果表明仿真信道模型的统计特性与参考信道模型相符,创造性地研究了街道移动通信环境下的信道模型,更大程度地拓展了室外C2C车载通信的研究与应用。
[Abstract]:With the rapid popularization of intelligent mobile terminals, the number of wireless communication users is increasing, and the demand for data transmission rate is increasing exponentially. With the development of broadband system, the improvement of data rate and the demand of various services, channel modeling has become a hot topic. In this paper, the channel modeling based on 3D three dimensional (3D) spatial link and its vehicle application are analyzed. Through the channel modeling in 3D space domain of macrocellular, the multi-input and multi-output multiple Input Multiple output MIMO-antenna array is deeply analyzed. Doppler shift, DSD, Power Spectral density, spatial fading correlation, SFCU, channel capacity and other factors that affect the performance of the system provide a theoretical basis for the performance analysis of wireless mobile communication systems. The research work in this paper is divided into the following four aspects: firstly, aiming at the multipath fading problem in the outdoor Macrocell-based mobile communication environment, the vertical component is introduced and the statistical channel model in the three-dimensional domain is established. The accuracy of channel variation description is improved. The algorithm of analyzing the probability density function of angle of arrival (AOAA) and arrival time of Arrival( toOAA) in azimuth and elevation plane is derived. The theoretical formula of space-time probability density closure of electromagnetic signals at mobile station (MS) and base station (BSs) is given. The related factors affecting space-time characteristics are analyzed in depth, which provides theoretical support for parameter estimation of multipath signals in vertical dimension. Secondly, based on the above model, the scattering body near MS is attenuated to a two-dimensional plane, and a three-dimensional statistical channel model based on scattering cluster is constructed. The probability density distribution of the multipath fading channel and the reverse link, including the angle of arrival, the arrival delay, etc., is derived numerically. The forward frequency shift caused by the frequency change is analyzed, and the numerical simulation results show that, The channel parameter estimation of the proposed model accords with the theoretical and practical communication environment, and describes the related characteristics of the multipath fading channel more comprehensively. Then, based on the above 3D scattering cluster channel model, the space-time distribution characteristics of fading channels are studied on the basis of uniform Linear Array, ULA) and uniform Circular Array, UCA) with MIMO multiple antennas. The effects of different azimuth distributions of the DOA signal on the MIMO performance in the scattering channel, including MIMO spatial correlation, channel capacity and antenna array configuration, are analyzed. Finally, a new statistical vehicle-borne communication model based on standard street scattering is constructed for vehicle-to-vehicle Car-to-car-to-C2C communication under outdoor wireless channel line-of-sight line of SightLoss / non-line-of-sight (Non-Line of SightLoss) transmission environment. Both the mobile transmitter (MTT) and the mobile receiver (MRM) are in mobile state. The analytical formulas of angle of arrival, angle of arrival, angle of arrival (AODs) and Doppler PSD are derived numerically, the Doppler parameters of the reference channel model are introduced and compared to verify the rationality and feasibility of the model. The influence factors of Doppler PSD, time autocorrelation function (ACFC) were studied by using control variable method. The results show that the statistical characteristics of the simulation channel model are consistent with the reference channel model, and the channel model under street mobile communication environment is studied creatively, which extends the research and application of outdoor C2C vehicular communication to a greater extent.
【学位授予单位】：南京信息工程大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN929.5

【参考文献】