A Source-Model Technique for the Analysis of Transient Electromagnetic Scattering by a Periodic Array of Cylinders

The source-model technique is applied to the solution of the problem of electromagnetic scattering by a periodic array of perfectly conducting cylinders illuminated by a transient plane wave. Special attention is given to the non-causality problem arising in the case of oblique incidence. This problem is alleviated by utilizing a transformation specifically tailored to the source-model formulation in a manner that significantly reduces the number of unknown future values that are required at each time step. Using this transformation, together with a band-limited extrapolator, it is possible to obtain a relatively stable solution that provides a satisfactory degree of accuracy for a wide range of incidence angles. To exemplify the use of this technique, we apply it to the case of circular cylinders.