Numerical Noise Introduced by the Alternating Direction-Implicit Scheme in FDTD for UWB Systems

Abstract

The numerical noise for spherical wave Ultra WideBand (UWB) signals originating from the Alternating Direction-Implicit (ADI) Finite Difference Time Domain (FDTD) scheme is quantified. A practical assessment is then provided to evaluate the numerical noise of the ADI-FDTD method relative to the FDTD method. The study reveals the influence of the temporal and spatial discretisation in conjunction with the maximum frequency of the excitation on the numerical noise. The result can be used for the determination of the temporal discretisation for the acceptable numerical noise increase compared with FDTD prior to running any simulation.