ACOUSTIC SCATTERING FROM A ROUGH CIRCULAR DISK

Scattering of an acoustic wave from a thin rough circular disk is stud ied using an integral equation method. The T matrix (transition matrix ), which governs the relation between the incident and scattered field s, is determined using an integral representation of the Helmholtz equ ation. The rough surface is modeled by a superposition of a number of sinusoidal surfaces that are randomly translated and rotated with resp ect to each other. Some numerical results for the scattered field are presented in the case of an incident plane wave. One conclusion is tha t the amplitude of the backscattered field is not only dependent on pa rameters like frequency, angle of incidence, and overall characteristi cs of the surface like rms height and correlation function. The exact geometry of the rough object is also vitally important for its scatter ing properties, which implies that a statistical approach to the probl em is of limited value. (C) 1996 Acoustical Society of America.