Stochastic Theory of Edge Diffraction: An Alternative Formulation

An alternative formulation is presented for the derivation of the results in [1] which allows to rigorously extend the validity range to any incidence/observation aspect provided that the standard deviation \sigma of the edge roughness is not large compared to the wavelength \lambda while the observation distance r is r>>\lambda. This was heuristically conjectured by Franceschetti, et al. (IEEE Trans. Antennas Propag., vol. 56, no. 2, pp. 437- 449, 2008) and supported by numerical examples, but without a rigorous proof