High-frequency scattering from a target in proximity to a randomly rough interface

Abstract

A T-matrix formalism for free-field target scattering and a Helmholtz–Kirchhoff integral equation in the Kirchhoff approximation for rough interface scattering are used to calculate high-frequency plane-wave scattering from a stationary target in proximity to an interface with random surface roughness. Scattering from targets located above and below the interface are considered: When the target is located above the interface, it is assumed that the scattered pressure field is simply the superposition of the target and rough interface scattered fields. When the target is located below the interface, it is assumed that target-interface multiple scattering can be ignored and that the scattered pressure field above the interface is given by the superposition of the field scattered from the interface and the field scattered from the target and transmitted through the interface when the field incident on the target is the transmitted plane-wave field. Numerical calculations indicate some of the effects of surface roughness and target physical and geometric parameters on the ability to ‘‘see’’ the target.