UWB定位系统中信号同步问题的研究

发布时间：2018-04-21 00:17

本文选题：超宽带 + 测距　；参考：《中国海洋大学》2014年硕士论文

【摘要】：超宽带（Ultra-Wide Band, UWB）无线通信是一种无需载波调制采用纳秒级别窄脉冲的通信技术。无需载波调制以及窄脉冲决定了UWB通信具有设备简单，穿透能力强，时间分辨率强，抗多径能力强的优势，因此定位精度极高。IEEE802.15.4a标准是IEEE提出的第一个精确测距定位的无线物理层标准。其中给出了UWB室内定位的信道完整模型，给出了九种信道实例。标准中给定的通信协议也是UWB定位所需要遵循的标准。但是其中也有不少要解决的问题，这些问题都会影响UWB室内定位的精度，例如对于单基站定位的研究，UWB定位中适用于单基站定位的通信协议，定位系统中的同步的问题。本论文主要针对单基站定位系统中单基站定位基站的设计、基站与定位标签之间的同步以及根据IEEE802.15.4a标准扩展或者重新设计适用于单基站的定位通信协议等问题进行了大量的研究。在查阅了大量的国内外文献资料的基础上设计了基于单基站的UWB高精度定位的系统模型；创新性的给出了定位通信帧的结构，特别是对于同步头和物理层协议头的设计，给出了时间戳报文的设计结构；提出了一种基于线性回归的双向时钟同步算法，对于帧和脉冲级别的信号传播时延的同步给出理论推导。论文的主要内容如下：首先介绍了常见的无线定位方式、UWB的基本定义、特点和对应的优势。阐述了UWB系统中同步问题的重要意义和研究价值以及国内外的研究现状。接着从测量时间（差）、角度、能量（幅度）的角度详细论述了无线定位的原理。主要有基于时间的TOA、TDOA和基于角度的AOA、以及基于能量的RSS。最后给出了定位算法中经常使用到的最小二乘法以及加权广义最小二乘法，并做出了详细的推导。为了进行高精度的仿真，设计了一种UWB单基站定位系统。对系统的基站建设、定位标签设计、信道做出了详细的论述，为接下来进行定位同步仿真打下了基础。在基站的建设中详细论述了UWB信号的选取调制以及定位标签和基站都需要考虑的信号的接收问题。在IEEE802.15.4a信道通信协议的基础上设计了基于单基站的UWB定位通信帧的组成结构，重点阐明了同步头的结构以及作用，扩展了物理层协议头的功能，最后设计了用于传输时刻信息的时间戳报文结构。介绍了经典双向测距的算法，接着提出了一种用于时钟同步的算法估算基站与定位标签之间的时钟频偏和时钟位移。在脉冲同步的基础上论述了估计信号传播时延的算法，在帧同步一级中提出了基于能量的非相干接收算法。
[Abstract]:Ultra-Wide bandwidth (UWB) wireless communication is a kind of nanosecond narrow pulse communication technology without carrier modulation. Without carrier modulation and narrow pulse, UWB communication has the advantages of simple equipment, strong penetration, strong time resolution and strong anti-multipath ability. Therefore, the IEEE 802.15.4a standard is the first wireless physical layer standard proposed by IEEE. The complete channel model of UWB indoor positioning is given, and nine channel examples are given. The communication protocol given in the standard is also the standard to be followed for UWB location. However, there are many problems to be solved, all of which will affect the accuracy of UWB indoor positioning, such as the research of single base station positioning, the communication protocol suitable for single base station positioning, and the synchronization problem in positioning system. This paper mainly aims at the design of single base station positioning base station in single base station positioning system. A lot of research has been done on the synchronization between the base station and the positioning label and the extension or redesign of the location communication protocol suitable for the single base station according to the IEEE802.15.4a standard. On the basis of consulting a lot of domestic and foreign literature, the system model of UWB high precision positioning based on single base station is designed, and the structure of localization communication frame, especially the design of synchronous head and physical layer protocol header, is presented innovatively. The design structure of timestamp message and a bidirectional clock synchronization algorithm based on linear regression are presented. The theoretical derivation of signal propagation delay synchronization at frame and pulse level is given. The main contents of the thesis are as follows: Firstly, the basic definition, characteristics and corresponding advantages of UWB are introduced. This paper expounds the significance and research value of synchronization in UWB system and the current research situation at home and abroad. Then the principle of wireless location is discussed in detail from the angle of measuring time, angle and energy. There are mainly time-based toado TDOA and angle based AOAA, as well as energy-based RSSs. At last, the least square method and the weighted generalized least square method which are often used in the localization algorithm are given, and the detailed derivation is given. In order to carry out high precision simulation, a UWB single base station positioning system is designed. The system base station construction, positioning label design and channel are discussed in detail, which lays the foundation for positioning synchronization simulation. In the construction of the base station, the selection and modulation of the UWB signal and the reception of the signals needed to be considered by the location label and the base station are discussed in detail. On the basis of IEEE802.15.4a channel communication protocol, the structure of UWB positioning communication frame based on single base station is designed. The structure and function of synchronous head are expounded, and the function of physical layer protocol header is extended. Finally, a time stamp message structure is designed to transmit time information. The classical bidirectional ranging algorithm is introduced, and then an algorithm for clock synchronization is proposed to estimate the clock frequency offset and clock shift between the base station and the location label. On the basis of pulse synchronization, the algorithm of estimating signal propagation delay is discussed, and an energy-based incoherent reception algorithm is proposed at frame synchronization level.
【学位授予单位】：中国海洋大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN925

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