Modeling 1-D FDTD transmission line voltage sources and terminations with parallel and series RLC loads

The finite-difference time-domain (FDTD) update equations to implement voltage sources and transmission line terminations with parallel or series RLC loads in a one-dimensional (1D) FDTD model are presented. A 1D FDTD model of a simple, lossless transmission line was developed. Later, it was extended to implement single circuit elements (e.g., capacitors, inductors, and resistors) and parallel or series RLC loads placed in parallel or series with the transmission line. In addition to the modeling of problems, the 1D FDTD transmission line model is useful in teaching students the time-domain analysis of transmission lines. The minimal computational demands of the 1D geometry allows for real-time displays of signal propagation.