建筑物对不同体制电磁脉冲时域响应数值分析

Numerical analysis of time-domain response for building to different electromagnetic pulses

针对一般建筑物内空间电场强度时域变化特点,采用时域有限差分方法,数值模拟单极性高斯脉冲、双极性微分高斯脉冲以及窄带调制方波脉冲平面波在建筑物内传播、反射及透射过程;并对比分析不同脉冲参数对空间场强最大值及分布的影响。在一定脉冲宽度的微分高斯脉冲激励下,建筑物空间内最大场强变化范围值较高,为3.0-5.5 dB,其空间场强增强分布区域较大,并随脉宽增加而减小,但脉冲的最小重复频率相对要求最高。相应脉宽的高斯脉冲造成空间最大场强及分布区域范围最小,而脉冲的最小重复频率所需最低。当载频为房间谐振频率的窄带脉冲入射下,空间最大场强变化范围值相对最高,空间场强增强区域总体趋势随脉冲载频频率单调增加。

To understand time-domain change characteristics of electrical field in the building, the simulation of three electromagnetic pulses propagating, reflecting and transmitting in a building was done by FDTD method. The influence of different pulse parameters on the maximum strength and distribution of electric field were generally analyzed. With the incidence of differential Gaussian pulses with varied pulse width, the maximum strength in the building changes within 3.0-5.5 dB and the range of reinforced field reduces as pulse width increases, and the required minimum pulse repetition frequency is the highest. The maximum strength and distribution area of electric field are the least in the building radiated by Gaussian pulses, of which the minimum repetition frequency is the lowest. When the operation frequency of narrow hand pulses is oscillation frequency of room, the maximum strength of electric field reaches the highest in the building, and the range of reinforced field becomes larger as operation frequency increases.