Fast Frequency Sweep Analysis of a Dielectric Rough Surface by Maehly Approximation

An efficient method for simulating electromagnetic scattering from a dielectric rough surface over a frequency band is proposed. The method is based on the Chebyshev series and the Maehly approximation. The tapered plane wave is chosen as the incident wave to avoid the artificial edge diffraction caused by the finite length of the simulated rough surface. The Gaussian rough surface is considered. Good agreement between the Maehly approximation and the exact results obtained by the method of moments (MoM) is found. The numerical results show that the Maehly approximation is superior to the MoM in terms of the CPU time required.