基于奇、偶模技术的FDTD分析对称结构频率选择表面

FDTD Analysis of Symmetrical FSS Based on Even-Odd Mode

推导了在单色波奇模和偶模入射情况下,周期边界条件的时域形式,并采用基于该奇、偶模周期边界条件的时域有限差分法(FDTD),对一个介质基片上的金属条带所构成的二维频率选择表面(FSS)在斜入射情况下的散射场进行了计算,数值结果与传统的双平面波法的计算结果吻合,而所需内存节约了50%,计算效率提高了一倍.

In this paper, periodic boundary conditions in the time-domain excited by single frequency odd mode and even mode incidence are derived. The scattered field of a 2-D FSS formed by infinite-periodic strip grating with a dielectric support and excited by a single-frequency obliquely incident plane wave is simulated with FDTD based on the odd-andeven mode technique. Compared with the dual-plane wave method, perfect agreement between numerical results is achieved. At the same time, the required memory size is reduced by 50% and the computation efficiency is improved by 100%. Validity and applications of the proposed method is demonstrated.