散射环境变化的室内时变TR-UWB信道特性研究

发布时间：2019-01-05 17:53

【摘要】：时间反演(Time Reversal,TR)技术能使超宽带(Ultrawideband,UWB)电磁波信号实现时间和空间同步聚焦,从而能简化接收端复杂度、降低发射功率、减小码间干扰以及提高信噪比等。随着对高质量无线通信需求的日益增长,时间反演超宽带(TR-UWB)通信技术可望成为未来无线通信的关键技术之一,因而对其的研究也日趋活跃。研究TR-UWB电磁波信道特性,并进一步建立信道模型,就成为了TR-UWB通信的重要研究内容。目前大多数的研究是非时变下的TR-UWB,但对于实际的无线通信系统,时变无线通信环境才是最常见的情况,因此时变环境下TR-UWB的研究显得尤为重要。研究时变环境下的TR-UWB,首先应该从其信道特性入手进行研究,找出其规律性;其次是通过对这些特性的研究,并结合时不变情况下的TR-UWB一般时空同步聚焦模型,尽可能找出一个更符合时变环境的TR-UWB信道模型。本论文采用基于时域有限差分方法(Finite Difference Time Domain,FDTD)的电磁仿真平台,进行了室内时变环境下的TR-UWB信道特性研究。本课题研究首先基于本团队开发的两个电磁仿真平台,进行平台筛选,选择仿真精度和效率相对更高的仿真平台进行后续的信道特性研究。接下来,利用所选择的仿真平台,对散射体移动情况下的室内时变TR-UWB电磁波传播特性(主要包括聚焦特性)进行研究,得到了一些有价值的研究成果。论文共分五章,主要内容如下:第一章介绍课题研究的背景、意义、当前TR-UWB信道特性的研究现状与本文的主要研究内容。第二章介绍仿真原理和工具,并给出仿真平台的选择以及精度和效率的检验。第三章介绍课题研究的信道特性参数,主要包括时间压缩率、聚焦增益、空间相关系数以及仿真环境的布置和具体的仿真步骤。第四章提取仿真空间中所设置的目标点和观察点的信道参数,分析了信道参数的变化趋势并总结规律。主要对目标点以及周围多个观察点处的信道参数进行综合分析和对比分析,并据此得出一些有价值的结论。最后一章对论文工作进行总结,并对今后工作进行展望。
[Abstract]:Time inversion (Time Reversal,TR) technology can realize time and space synchronous focusing of ultra-wideband (Ultrawideband,UWB) electromagnetic signals, which can simplify the complexity of receiver, reduce transmission power, reduce inter-symbol interference and improve signal-to-noise ratio (SNR). With the increasing demand for high quality wireless communication, time inversion ultra-wideband (TR-UWB) communication technology is expected to become one of the key technologies in future wireless communication, so the research on it is becoming more and more active. The study of TR-UWB electromagnetic channel characteristics and further establishment of channel model has become an important research content of TR-UWB communication. At present, most of the researches on TR-UWB, are non-time-varying, but for practical wireless communication systems, time-varying wireless communication environment is the most common case, so the study of TR-UWB in time-varying environment is particularly important. The study of TR-UWB, in time-varying environment should begin with its channel characteristics and find out its regularity. Secondly, by studying these characteristics and combining with the general spatio-temporal focusing model of TR-UWB under time-invariant condition, we can find out a TR-UWB channel model which is more suitable for time-varying environment as far as possible. In this paper, the electromagnetic simulation platform based on finite-difference time-domain method (Finite Difference Time Domain,FDTD) is used to study the characteristics of TR-UWB channel in indoor time-varying environment. Firstly, based on the two electromagnetic simulation platforms developed by the team, the platform is screened, and the simulation platform with higher simulation accuracy and efficiency is selected to study the channel characteristics. Then, using the selected simulation platform, the propagation characteristics (including focusing characteristics) of indoor time-varying TR-UWB electromagnetic wave in the case of scatterer moving are studied, and some valuable research results are obtained. The thesis is divided into five chapters. The main contents are as follows: the first chapter introduces the background and significance of the research, the current research status of TR-UWB channel characteristics and the main research content of this paper. The second chapter introduces the simulation principle and tools, and gives the choice of simulation platform and the test of accuracy and efficiency. In chapter 3, the channel characteristic parameters are introduced, including time compression ratio, focus gain, spatial correlation coefficient, simulation environment layout and simulation steps. In chapter 4, the channel parameters of the target point and the observation point in the simulation space are extracted, and the variation trend of the channel parameters is analyzed and the rules are summarized. The channel parameters of the target point and the surrounding observation points are analyzed and compared, and some valuable conclusions are obtained. The last chapter summarizes the work of the thesis and looks forward to the future work.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN925

【共引文献】