ASA 127th Meeting M.I.T. 1994 June 6-10

5pUW13. Forward and inverse scattering from rough surfaces at low grazing incidence.

Mark Spivack

Dept. of Appl. Math. & Theor. Phys., Univ. of Cambridge, Cambridge CB3 9EW, UK

In acoustic wave scattering from rough surfaces at low grazing angles the usual approximations are known to break down. In the forward-scattering regime this case is often treated by the parabolic integral equation method. The scattering of plane waves within this formulation is considered, and effective reflection coefficients are derived for slightly rough surfaces. Of the higher-order statistics, the dependence of the diffuse and specular components upon incident angle is also examined. The problem of surface reconstruction can be expressed in terms of coupled integral equations; it is explained how in the parabolic case these are easily treated. A major problem, however, is backscatter; a nonparabolic approach to this problem for low-grazing angles is described. [Work supported by Smith Institute Research Fellowship.]