电磁脉冲在地下的传播特性研究

对于电磁脉冲的传播来说,大地是一道天然的障碍,因此研究电磁脉冲在地下的传播规律,并将其用于线路和设备的抗电磁干扰,是很有意义的。本文分析了HEMP电场在地下的传播规律,并比较了HEMP和雷电磁脉冲(LEMP)、超宽带电磁脉冲(UWB EMP)在地下的传播情况,比较了HEMP在地下和地上的传播情况,结果表明:高频电磁脉冲电场在地中随深度增加而快速减小,低频电磁脉冲变化较小;高频电磁脉冲电场随大地电导率减小而增大、脉宽变宽,随大地介电常数增大而减小,随入射波极化角和方位角增大而减小,随俯仰角增大而增大。然后,根据电磁脉冲在地下的传播规律提出了电磁防护措施和建议。本文的研究有利于指导地下设备的电磁防护设计。

Research on Characteristics of Electromagnetic Pulse Propagating into Earth

As to the propagation of EMP,the earth is a natural obstacle,so it’s very significative to research the laws of EMP propagating into earth,which can be used into the electromagnetic protection of cables and devices.In this paper,The propagation laws of High-altitude electromagnetic pulse(HEMP) is researched,and propagation of HEMP,LEMP and UWBEMP,HEMP into earth and above earth are compared.Results show that: the electric field of high frequency EMP in earth weakens rapidly with the increase of depth,strengthens with the decrease of earth conductivity and permittivity,and the pulse width increases with the decrease of earth conductivity,weakens with the increase of polarization angle and azimuth angle,but strengthens with the increase of pitching angle.But the electric field of low frequency EMP in earth weakens slowly with the increase of depth.Based on these laws,some electromagnetic protection measures are proposed.The research in this paper is helpful to provide guidance for the protection design of electronic devices in the earth.