梁东升



摘 要:各导航台的信标天线高度由多种因素决定,为实现多普勒甚高频全向信标信号的良好覆盖,架高天线的高度往往与地网的大小尺寸有一定关系,只有满足一定关系,才能让信号辐射到达最佳效果。本文以多普勒甚高频全向信标为基础,建立数学模型,分析天线高度与地面反射、地网反射的关系,并用实例分析地网反射的理论与实际效果。
关键词:多普勒甚高频全向信标;反射;波瓣零点
中图分类号:V351.37文献标识码:A文章编号:1003-5168(2021)08-0102-03
A Case Study of the Ground Net Reflection of Doppler
VHF Omni-directional Range
LIANG Dongsheng
(Henan Bureau of CAAC Central and Southern Regional Administration,Zhengzhou Henan 450000)
Abstract: The beacon antenna height of each navigation station is determined by many factors. In order to achieve good coverage of Doppler very high frequency omnidirectional signal, the height of the antenna is often related to the size of the ground grid. Only when the relationship is satisfied can the signal radiation achieve the best effect. Based on Doppler very high frequency omnidirectional, this paper established a mathematical model to analyze the relationship between antenna height and ground reflection and ground grid reflection, and analyzed the theoretical and practical effects of ground grid reflection with examples.
Keywords: Doppler VHF omni-directional range;reflection;lobe zero
1 研究背景
多普勒甚高頻全向信标(Doppler VHF Omni-directional Range,DVOR)是一种为飞机提供精确方位的无线电导航设备,被广泛应用于国内外各大机场,可以实现给飞机定位、沿航路导航、实施进近和区域导航等功能。随着现代化发展速度不断加快,城市化进程持续推进,高楼大厦和各具特点的建筑物也随之增多。现代化建筑给城市建设增添了亮点,但高度超出民航规范标准的建筑物会遮蔽导航设备信号,导致无法对飞机进行准确定位。将原有的多普勒甚高频全向信标(DVOR)天线架高是解决此类问题的一种方法,但是单纯地架高天线又会引发信号覆盖盲区增加的问题,所以需要合适的地网尺寸来配合天线高度,从而发挥信号反射的最佳效果。本文建立数学模型分析地网尺寸和天线高度的关系,从某导航台的实例的理论和实际两个方面来研究反射信号的效果和差异。
2 基本原理
2.1 多普勒效应
当发射天线和接收天线没有相对运动时,接收到的信号频率就等于发射的信号频率。……