基于时域有限差分方法对非对称十字形周期金属结构在太赫兹波段的透射特性进行了数值模拟研究。研究结果表明，对称十字形周期金属结构，其太赫兹透射谱出现陷波效应。保持十字形金属的长、宽、周期不变，研究偏移量对太赫兹透射特性的影响，得到随着偏移量的增加，透射凹陷所在的频率位置向低频方向移动；通过旋转样品，研究非对称十字形结构在太赫兹波段的偏振特性，即改变太赫兹电场偏振方向相对于金属的角度，发现非对称十字形周期金属结构对偏振比较敏感；而对称十字形周期金属结构无偏振依赖性。

The numerical simulation is applied to analyze Terahertz (THz) transmission properties of the asymmetrical cross periodic metallic structures, which is based on the finite-difference time-domain (FDTD) method. The results show that there exists the band elimination in the THz transmission spectrum for the cross metallic structures. When we investigate the effect of THz transmission properties caused by the offset and keep the length, width and period of the metallic structures unchanged, the frequency location of the transmission depression moves towards low frequency as increasing the offset of one metallic. By rotating the sample and changing the polarization of THz electric field related to the direction of one metallic, THz transmission of the asymmetrical cross metallic structure is strongly sensitive to the polarization, while the symmetrical cross structure is independent of THz polarization.