基于中波广播信号测量法的建筑物雷电电磁脉冲屏蔽效能分析

Analysis of building shielding effectiveness against lightning electromagnetic pulse based on medium wave broadcast signal measurement

本文提出使用调幅/调频(AM/FM)场强仪测试中波信号电平,计算建筑物对雷电电磁脉冲(LEMP)的屏蔽效能。选取两个不同频点的中波电台模拟LEMP信号源,测量建筑物不同垂直和水平空间的信号电平,计算屏蔽效能值及衰减量。对测试数据进行线性回归分析,结果表明垂直空间上顶楼的LEMP衰减量最大,水平空间内距离门窗等屏蔽网格越远,信号衰减量越大。测试还发现,衰减量与信号频率、测试高度正相关。试验结论可为电子信息系统的LEMP屏蔽设计、屏蔽效能检测提供理论数据和应用支持。

In this paper,it is proposed to use the amplitude modulation(AM)/frequency modulation(FM)field strength meter to test the medium wave signal level to calculate the shielding effectiveness of the building against the lightning electromagnetic pulse(LEMP).Two different frequency points of medium-wave broadcast stations are selected to simulate LEMP signal source to measure signal level at different vertical and horizontal space of the building.The shielding effectiveness and attenuation amount are calculated.The linear regression analysis of the test data shows that the top floor in the vertical space has the largest attenuation of LEMP,and in horizontal space,the farther away from the window and other shielding grids,the greater the signal attenuation.It is also found that attenuation is positively correlated with signal frequency and test altitude.It provides valuable theoretical data and application support for LEMP shielding design and shielding efficiency detection of electronic system.