用FDTD法计算架设在有损地面上高频段单极天线辐射特性

Radiant Characteristics of HF Monopole Antenna Located on Lossy Ground Computed by FDTD Method

在高频波段 (2～ 30MHz) ,由于天线架设在环境复杂中 ,计算其辐射特性和电磁波传播特性非常困难 ,少有文献对此进行分析 .随着高频技术的发展 ,这一现实问题迫切需要解决 .本文用时域有限差分法 (FiniteDifferenceTimeDomain)对这类问题进行了分析计算 .文章计算了架设在有损地面上的单极天线辐射特性 ,并分析了架设海岸边的单极天线辐射的电磁波经过一段有损陆地后 ,其远区电磁场随陆地距离的变化特性 .在计算中引入了表面阻抗法概念 。

For high frequency electromagnetic wave(2～30MHZ),it is very difficult to calculate radiant and transmittal characteristics of antenna located in complex environment.With the development of high frequency technology,the problems need to be solved imminently.In this paper,finite difference time domain method is used to calculate this problem.First the radiant characteristics of the monopole located on lossy ground are calculated.Then the characteristics of the electromagnetic wave transmitted by antenna located near coast passing a section of lossy ground are analyzed,and the characteristics of far electromagnetic strength related to the length of lossy ground are given.The surface impedance is used in this paper,that reduces calculation amount and memory space to a very marked degree.