New tlm formulations for debye medium

Abstract This Letter introduces new transmission-line-matrix (TLM) algorithms for simulating propagation of electromagnetic waves in debye medium. These algorithms, based on the symmetrical condensed node (SCN-TLM) and novel voltage sources, exploit the auxiliary differential equation (ADE) and the exponential time differencing (ETD) schemes. In terms of memory, the requirement of ETD-TLM method is similar to that of ADE-TLM method. The accuracy of both resulting algorithms is demonstrated by calculating the reflection coefficient of a Gaussian pulse at an air-water interface. The comparison of the numerical results of the ETD-TLM and the ADE-TLM with analytic values indicates that the ETD-TLM is more accurate than the ADE-TLM algorithm.