Application of the TLM method to two‐dimensional scattering problems

In this paper the application of the TLM method to electromagnetic scattering problems is investigated. To achieve the full computational benefits of using a time‐domain numerical method, pulse excitation can be applied together with Fourier transformation of an output impulse response to yield frequency‐domain results over a wide bandwidth. The configuration of the mesh is the same as that used in FD–TD scattering simulations (i.e., separation of the simulation space into total and scattered field regions). To terminate the exterior boundaries of the mesh, absorbing boundary conditions are applied to absorb the outward travelling waves. The effect of the absorbing boundaries on both time‐ and frequency‐domain results is investigated. Frequency‐domain scattered far‐field patterns are presented for perfectly conducting square and circular cylinders illuminated by an incident plane wave (TM case). Forward and back scattering cross‐section results obtained from a single TLM simulation indicate both the accuracy and efficiency of the method for calculating frequency‐domain results over a wide bandwidth.