An unconditionally stable finite-difference time-domain (US-FDTD) method based on wave equation is introduced by making use of Laguerre polynomials as basis functions for expanding field components in time. This new wave-equation-based FDTD scheme is not only unconditionally stable but also requires less memory usage. Comparisons among the traditional FDTD, the conventional Laguerre-polynomial US-FDTD, and this proposed scheme are presented in the numerical examples in terms of the memory usage and computational time. (C) 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51:529-532, 2009...
