沿海VHF信号传播特征分析

发布时间：2018-06-04 00:12

本文选题：沿海 + VHF　；参考：《大连海事大学》2017年硕士论文

【摘要】：VHF作为海上通信方式已有几十年的历史,是海上通信的重要手段,随着AIS和VDES系统的推广应用和实施,VHF数字通信对信道模型等信号传播特征提出了更高的要求。沿海领域环境复杂多样,不同区域的VHF信号传播特征直接影响船岸之间的通信,从而影响船舶航行安全。基于此,研究和分析沿海区域VHF信号传播特征,无论在技术创新方面还是应用实践方面都具有积极的现实意义。论文首先设计实现了 VHF信号传播测量平台,平台硬件系统由信号发生器、信号分析仪、功率放大器、全向天线、同步实验箱等部分组成;其中,同步实验箱由铷钟和GNSS模块组成,用GNSS模块给铷钟校准时间,以减小数据延时误差;平台软件系统基于Windows下的Qt开发环境设计开发,利用VISA库和SCPI指令实现计算机和测量仪器的远程通信、测量仪器的自动化配置、VHF信号自动化收发保存等功能。然后,设计了基于MATLAB开发环境的沿海VHF信号传播特征的数据处理平台。该平台分为两部分,一部分基于实地测量数据计算发射机和接收机不同距离时的信道冲激响应和功率延迟分布,计算多径平均时延扩展和均方根时延扩展;另一部分基于经典大尺度模型建立信道模型库,将实地测量数据和各个大尺度信道模型进行对比,计算残差平方和与拟合优度。基于上述系统平台,针对大连星海湾大桥附近海域进行了实地环境试验,对试验数据进行了处理分析,分析了小尺度衰落中的多径效应和大尺度衰落,总结了沿海VHF信号传播多径特点,对比了各个模型的残差平方和与拟合优度。
[Abstract]:As an offshore communication mode, VHF has been used for decades, and is an important means of maritime communication. With the popularization and application of AIS and VDES system, it has put forward higher requirements for the signal propagation characteristics such as channel model. The environment of coastal areas is complex and diverse, and the characteristics of VHF signal propagation in different regions directly affect the communication between ships and shores, thus affecting the safety of ship navigation. Based on this, the study and analysis of the characteristics of VHF signal propagation in coastal areas have positive practical significance in both technological innovation and practical application. The hardware system is composed of signal generator, signal analyzer, power amplifier, omnidirectional antenna, synchronous test box and so on. The synchronous test box is composed of rubidium clock and GNSS module. The calibration time of rubidium clock is calibrated by GNSS module to reduce the data delay error. The platform software system is designed and developed based on QT development environment under Windows. The functions of remote communication between computer and measurement instrument and automatic configuration of measurement instrument are realized by using VISA library and SCPI instruction. Then, the data processing platform of coastal VHF signal propagation characteristics based on MATLAB development environment is designed. The platform is divided into two parts. One part calculates channel impulse response and power delay distribution at different distances between transmitter and receiver based on field measurement data, and calculates multipath average delay spread and root mean square delay spread. In the other part, the channel model base is established based on the classical large-scale model, and the field measurement data are compared with each large-scale channel model to calculate the sum of squared residuals and the goodness of fit. Based on the above system platform, field environmental tests are carried out on the sea area near Dalian Xingwan Bridge. The experimental data are processed and analyzed, and the multipath effect and large-scale fading in small-scale fading are analyzed. The multipath characteristics of coastal VHF signal propagation are summarized, and the sum of residual square and the goodness of fit of each model are compared.
【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U675.7;TN011

【相似文献】