Electromagnetic transient scattering analysis in time-domain—comparison of TLM and TDIE methods

Here we consider two popular techniques useful for time domain signature analysis of direct scattering problem i.e., given the incident waveform and the target geometry, find the scattered field. We present in this paper a comparison of two popular time domain numerical techniques, viz., the transmission line matrix (TLM) method and the finite-difference time-domain (FDTD) method for electromagnetic scattering problems. Even though there are many similarities between the two methods, the modeling philosophy is different. Whereas in FDTD Maxwell’s equations are solved using a differencing scheme, in TLM a scattering approach akin to Huygens principle is implemented by replacing the space domain with a system of interconnected transmission-lines. The comparison is made via standard canonical shapes, a dielectric cube, and a dielectric sphere, to address the factors affecting accuracy, efficiency, and the required computer resources.