利用有限积分法对电磁脉冲与带缝腔体孔缝耦合特性进行研究。选取窄缝为mm 量级微小孔缝作为研究对象，借助耦合函数，分析了核电磁脉冲与单层腔体、嵌套腔体内、外窄缝平行分布与垂直分布2 种情况下的耦合函数。结果表明：当入射波电场矢量方向与窄缝短边平行，即入射角θ =0°时，内、外窄缝平行分布耦合进入腔体的电磁能量在内窄缝处发生第2 次场增强效应；而内、外窄缝采用垂直分布的相对位置，在内窄缝处的电场值仅为几伏每米，此分布能有效降低电磁脉冲对电子器件的干扰。

Coupling processes of electromagnetic pulse into cavities with slot are investigated by Finite Integral(FIT) method. Slots with dimension of several millimeters are selected as research objects. The coupling functions about parallel distribution and vertical distribution of the slots are analyzed with the incident angleθ =0o. It is found that electromagnetic energy coupling into the cavity in the parallelly distributed slots would behave the second resonance effect at the point of the internal slot. At the same time, the peak electric field is only a few volts per meter at the point of the internal slot of the vertically distributed slots. Therefore, this distribution can effectively reduce the interference of electromagnetic pulses on electronic devices.