An FFT-based kirchhoff integral technique for the simulation of radio waves in complex environments

Abstract

[1] Kirchhoff integral (KI) techniques provide an effective means of simulating radio wave propagation in nonhomogeneous media with complex boundaries. In particular, these techniques can handle quite general boundary topography. Due to the translation-]dependent nature of their kernels, however, they cannot take advantage of the fast Fourier transform (FFT) techniques that give the parabolic equation methods their speed. In this paper it is shown that, by means of approximate kernels, the KI technique can be recast in a form where FFT techniques can be applied. Furthermore, through the use of effective reflection coefficients, the technique can handle quite general boundary topography without the need for boundary flattening transformations. The technique is demonstrated through the simulation of several complex 2-]D and 3-]D radio wave propagation scenarios. © 2010 by the American Geophysical Union.