Time-step program for the sub-cell FDTD modeling of apertures with finite depth

Article type: Research Article

Authors: Xu, Chunhua^{a; *} | Deng, Zhengdong^a | Xiong, Run^b | Deng, Feifan^a

Affiliations: [a] PLA University of Science and Technology, Nanjing, Jiangsu, China | [b] Engineer Academy of PLA, Xuzhou, Jiangsu, China

Correspondence: [*] Corresponding author: Chunhua Xu, PLA University of Science and Technology, Haifuxiang 1st, Nanjing 210007, Jiangsu, China. E-mail: [email protected]

Abstract: When using sub-cell algorithms to model the coupling of apertures with finite depth in the finite-difference time-domain (FDTD) method, time-step size is required to be reduced to avoid instability. In this work, a time-step program is proposed for the stable modeling of apertures with finite depth using sub-cell algorithms. A sub-cell area related time-step reduction coefficient is introduced to ease the steady reduction of the time-step size firstly. Then a modified algorithm is given for sub-cells whose area is extremely distorted. Numerical results demonstrate that the proposed time-step program is an accurate and stable modeling of aperture coupling without resulting in significant time-step reduction.

Keywords: Aperture coupling, FDTD method, stability, time-step program

DOI: 10.3233/JAE-140047

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 47, no. 1, pp. 255-262, 2015