Implicit Element Clustering for Tetrahedral Transmission-Line Modeling (TLM)

Time-domain electromagnetic simulations employing unstructured tetrahedral meshes can be sensitive to local mesh characteristics. In particular, the maximum permissible time step for stable operation can be unacceptably small. In this paper, a cell clustering technique is described for the transmission line modeling algorithm that reduces the sensitivity to local mesh characteristics and permits substantial increases in time step to be made without compromising accuracy or stability.