A Fast Parallel Solution Technique for Large Periodic Structures Based on FEM-DDM

In this letter, a fast solution technique based on the finite-element approximation and the domain decomposition method for the analysis of superlarge electromagnetic periodic structures is presented. This technique reduces memory requirements and computational time by decomposing the original periodic structure into several nonoverlapping subdomains according to geometrical repetitions and utilizing the characteristics that most of the subdomains will generate identical system matrices. An adaptive parallel framework considering periodic element features is designed to further accelerate the proposed technique. Through comparisons with existing methods and the commercial software ANSYS HFSS, the benefits and accuracy of the proposed technique are demonstrated. Finally, a microstrip patch antenna array with 10 000 elements and a large waveguide slot antenna array with 4096 slots are simulated showing the power of the presented method.