In this letter, a spatial modes filtering finite-element time-domain (SMF-FETD) method combined with dual-field domain decomposition (DFDD) is proposed for analyzing 2-D electromagnetic structures with fine features. The SMF-FETD method can obtain unconditional stability by removing unstable modes. Thus, a large time step is available in the SMF-FETD method though the fine features exist. However, the global eigenvalue solution is required in the SMF-FETD method, which brings a great burden on the computing memory and time. To solve this problem, the DFDD technique is introduced into the SMF-FETD method. The technique solves the SMF-FETD equations in each subdomain and relates the adjacent subdomains explicitly using the equivalent electromagnetic currents on the subdomain interfaces. It can greatly reduce the computing memory and time. Numerical examples are presented to verify the accuracy and effectiveness of the proposed DFDD-SMF-FETD method.

中文翻译：

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结合域分解模拟精细电磁结构的空间模式滤波 FETD 方法


在这封信中，提出了一种结合双场域分解（DFDD）的空间模式滤波有限元时域（SMF-FETD）方法，用于分析具有精细特征的二维电磁结构。 SMF-FETD方法可以通过去除不稳定模式来获得无条件稳定性。因此，尽管存在精细特征，但 SMF-FETD 方法仍可使用大时间步长。然而SMF-FETD方法需要全局特征值求解，这给计算内存和时间带来了很大的负担。为了解决这个问题，DFDD技术被引入到SMF-FETD方法中。该技术求解每个子域中的 SMF-FETD 方程，并使用子域界面上的等效电磁电流显式关联相邻子域。它可以大大减少计算内存和时间。数值例子验证了所提出的 DFDD-SMF-FETD 方法的准确性和有效性。