单脉冲平面波以不同方向入射时开孔屏蔽室内的耦合场研究

Analysis of the Coupling Field Inside a Rectangular Shielded Enclosure with an Aperture

采用时域有限差分(FDTD)法计算了开孔屏蔽室对单脉冲平面波的耦合,取得了与实测波形一致的结果。计算结果表明:若入射波传播方向垂直于开孔面,则屏蔽室内的耦合场仅取决于屏蔽腔体的谐振特性;若入射波传播方向平行于开孔面,则屏蔽室内的耦合场为具有源特征的低频分量与屏蔽室内的高频谐振波分量组成。

The finite-difference time-domain（FDTD） method was used to study the plane wave coupling into a rectangular shielded enclosure through a aperture, and the theoretical prediction agree with the measured characteristics well. Results show that： ① if the wave sources travel vertically to the aperture, the coupling field inside the cavity is mainly composed of different modes resonance fields;② if the wave sources travel along the direction parallel with the aperture, the coupling field is the sum of the lower-frequency components with the sources＇ characteristics and the higher-frequency resonance fields of the cavity.