为了研究开不同形状孔的金属腔体的电磁耦合规律,利用电磁仿真软件FEKO建立了腔体模型和所需的电磁场环境。研究表明:腔体近源端附近电磁波分布呈现明显的反射;开正方孔腔体内电磁场强度剧变发生在频率为700MHz时,电磁耦合的谐振频率为700MHz,未发现开长方孔腔体的强电磁耦合现象;在波长与腔体尺寸可比拟时,电磁波在壳体远端有明显的绕射现象;腔体使电磁场的垂直远场分布发生畸变,主要取决于腔体的反射;腔体内的电磁场在z,y方向上相对于孔具有非对称性,腔体对外界电磁场的耦合具有明显的边缘效应。
The electromagnetic simulation software FEKO was applied to establish cavity model and the needed electromagnetic environment to study the electromagnetic coupling law of different shapes of metal cavity. It was showed that : the electromagnetic wave near the source presented obvious reflection; the intensity of electric and magnetic field in the cavity with square hole changed tempes- tuously at frequency of 700MHz, which was the resonance frequency of electromagnetic coupling; there was no strong electromagnetic coupling phenomenon in the cavity with oblong hole; obvious electromagnetic wave diffraction happened at a distance from the cavity; the vertical far field changed greatly, which was mainly affected by the cavity reflection; in z, y direction the internal electromagnetic fields has asymmetry nature to the cavity; and the body has obvious comer effects to the coupling of the electric magnetic field of the external world.