Fast simulations of electromagnetic scattering from rough surface over a frequency band using asymptotic waveform evaluation technique: horizontal polarization

The asymptotic waveform evaluation (AWE) technique combined with the scalar integral equation and the tapered plane wave is chosen to fast simulate the electromagnetic scattering from rough surface over a frequency band under horizontal (H) polarization in this paper. The tapered plane wave with the energy in a narrow beam is chosen as the incident wave to avoid the artificial edge diffraction due to the finite length of the simulated rough surface. And the scalar integral equation is used to obtain the surface unknowns along the rough surface induced by the incident wave. The validity and efficiency of the AWE are shown by comparing with the repeated calculation at every finer frequency increment through the method of moments (MoM). The influences of several important parameters, such as root-mean-square height, correlation length and incident angle are studied and discussed. And in this paper, the complex frequency hopping technique is also used to extend the validity of AWE.