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:
xuchunhua123456@126.com
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
