A new algorithm for analysing lumped parameter elements within the 3-D FDTD method

A new method of including linear and nonlinear lumped elements within the three-dimensional finite-difference time-domain (FDTD) algorithm is presented. Unlike previous approaches, the method can accurately analyze lumped elements of any physical size (i.e. elements can occupy more than one cell). Instead of using a discretized conduction current term in Maxwell equations to represent lumped element behaviour the media parameters associated with those grids occupied by the lumped element is changed according to the functional current-voltage equation that governs the lumped element behaviour. Compared with previously published material the method reported here is stable, and is simple to implement. Numerical agreement is obtained when compared with MDS simulation results.