Yuan Zhang
Richard L. Weaver
Dept. of Theor. and Appl. Mech., Univ. of Illinois, Talbot Lab., 104 South Wright St., Urbana, IL 61801
The problem of a plane harmonic wave obliquely incident from a homogeneous ideal fluid space upon a random fluid layer is considered. The thin layer is taken to have properties that vary randomly only in the in-plane directions. A first Born approximation is used and the average intensity of the incoherent part of the scattered wave is found to be proportional to the two-dimensional spatial Fourier transform of the auto- and cross-covariance functions of the layer, within the confines of the validity of the first Born approximation. Therefore, the inverse scattering problems may be straightforward, provided the necessary experimental data of the incoherent wave can be found. A sufficient condition is also given to estimate the range in which the second-order term in the Born series can be ignored. [Work supported by the National Science Foundation Solid Mechanics Program, Grant No. MSM-91-14360.]