High-frequency electromagnetic field analysis using pseudo-quadruple precision in subdomain local solver

. The purpose of this study is an improvement of convergence properties of an interface problem in the high-frequency electromagnetic field finite element analysis based on the iterative domain decomposition method by introducing a pseudo-quadruple precision into the subdomain solver. In the high-frequency electromagnetic field analysis, it is well known that when the numerical model becomes huge scale, the convergence properties of the interface problem become extremely poor. To improve the deterioration of the convergence property in the interface problem, we propose to introduce a pseudo-quadruple precision into the iterative solver based on the conjugate gradient method in the subdomain problem. The pseudo-quadru-ple precision is constructed by ordinary double precisions. In this study, we apply the pseudo-quadruple precision for solving subdomain problems in the iterative domain decomposition method. As a result, we can obtain improvement of convergence properties in the iterative solver for the interface problem.