Determination of the CFL number for FD-ADI-FDTD based on the required accuracy

Ultra wideband (UWB) systems have a wide range of applications from microwave imaging to communication purposes. Major advances towards the realization of these applications require a system modeling which produces UWB signal waveforms after propagation in a lossy media. The frequency dependent (FD) finite difference lime domain (FDTD) method is a popular method to do so but is faced with the Courant-Friedrichs-Levy (CFL) condition which limits its time discretisation size. The alternating direction implicit (ADI) method has been introduced to FDTD to remove that CFL condition. This paper has novelty in quantification of the contribution of the spatial discretisation on error of FD-ADI-FDT and, based on this result, in proposing the scheme to determine the temporal and spatial discretisation from the viewpoint of accuracy