受限空间实现电波高效覆盖的天线及漏泄波导理论与技术研究

The radio wave coverage of wireless communication is the important guarantee for safety operation of the mobile carriers in confined areas. The type and layout of the antennas used in available radio wave coverage systems in confined areas are hard to support the development of wireless communication towards the high bit rate and high reliability, and already become one of the key problems for the automatic control of train running in the confined area. This project will start from the common basic problems of the radio wave coverage in confined areas. Study the basic problems of the field distribution, multi-path effect, expansion of signal, transmission bit rate, energy efficiency and the effect range of the system constructed by the antenna and environment, and then establish the parameter system for evaluating the efficiency of the radio wave coverage. This project will conduct research on the new antenna structures that can realize the high efficient radio wave coverage in typical confined areas, like the railway tunnels, subway, city light rail, by applying the new achievements in antenna area and using the radiation pattern shaping technologies. Also, the project will analyze the near field composition and transformation mechanism of near field to far field of the leaky waveguide, study the effect of slot shape, arrangement, and neighboring environment on the radiation field, and fabricate the environment adaptable leaky waveguides. Based on the above study, the project will further do researches on the layout optimization of the multi-antenna and multi-leaky waveguide systems, and the effect of the high speed carrier and its antenna on the radio wave coverage. In addition, in order to meet the demands of the reliable wireless communication in mine tunnels and the development trend of the public wireless communication in confined areas, this project will also do researches on the high efficient radio wave coverage systems in mine tunnels and in confined areas (for public wireless communication) by using antennas and leaky waveguides.

受限空间无线通信电波覆盖是其中移动载体安全运行的重要保障，现有电波覆盖系统在天线结构及布局上已难以支撑无线通信向高速率、高可靠性方向发展，已成为制约列车运行控制自动化的主要问题之一。本项目将从受限空间电波覆盖的共性基础问题出发，研究天线结构及空间环境共同作用下的场分布、多径效应、信号扩展、传输速率、系统能效及作用范围等基本问题，建立受限空间高效电波覆盖评价参数体系；针对铁路隧道、地铁、城市轻轨等典型受限空间，应用天线领域最新成果并借助方向图赋形技术，研究可实现电波高效覆盖的天线结构；通过分析漏泄波导近场组成及近、远场转换机制，研究孔缝形状、排列方式及附近环境对辐射场的影响，研制环境适应型漏泄波导；在此基础上，研究多天线多漏泄波导的优化布局，研究高速载体及其天线对电波覆盖的影响。此外，针对矿井隧道专用无线通信安全需要以及受限空间公众无线通信发展需求，研究相应的天线及漏泄波导高效电波覆盖系统。

受限空间高效电波覆盖是其中无线通信的重要基础和保障。现有受限空间电波覆盖的研究还缺乏系统性，受限空间所使用的天线类型也相对单一，难以满足移动通信的发展需求，尤其是难以适应高速列车运行控制的发展。本项目以隧道类受限空间和列车专用无线通信为应用背景，研究受限空间各类天线及漏泄波导产生的电波覆盖特性，研究适用于受限空间的新型漏泄波导和天线，研究新的受限空间电波覆盖方案，为今后受限空间高速列车无线通信系统设计和实现提供技术支撑；同时本项目也兼顾公众移动通信系统的发展需求，研究受限空间中的毫米波电波覆盖系统。本项目所取得的重要成果如下：1）在受限空间电波覆盖高效算法上，提出了改进型抛物方程精确求解方法；将射线追踪、抛物方程等方法与时域有限差分方法相结合，形成了高效混合算法；将天线的方向特性引入模式分析方法，从而可有效分析传播模式与天线辐射特性的关系。2）在电波覆盖规律研究上，从理论和实验两方面系统地研究了各类天线在隧道类受限空间中的电波覆盖规律，分析了极化、增益、波瓣宽度、波束指向、天线位置等多种因素对电波覆盖的影响，为受限空间电波覆盖系统的选型提供了重要的基础数据。3）提出了5.8GHz频段的新型圆极化矩形漏泄波导和具有周向方向性的新型双缝隙漏泄波导，并进行了加工测试；研制了实用化的2.4GHz和1.7GHz频段的矩形漏泄波导；合作研制了5.9GHz频段的矩形漏泄波导，为受限空间以及山区列车无线通信的发展提供了基础结构。4）提出了高增益漏波天线阵列、高效率漏波天线阵列馈电系统以及高效率受限空间波束赋形天线等一系列新型天线，为受限空间高效电波覆盖提供了手段。5）提出了新型受限空间智能化天线系统，可以根据移动体的位置或速度自动调整波束宽度和指向，跟踪移动目标，从而实现能量的高效利用和数据的可靠传输。该项目的研究成果进一步完善了天线和电波传播理论，对铁路无线通信的发展具有积极推动作用。