Modeling of scattering by objects on the seabed

Abstract

This paper describes some of the theory and implementation issues of modeling the backscattered energy from cylindrical or spherical objects lying on the seabed. The model utilizes a single-scatter approximation; this approximation is compared to full multiple scattering solutions to verify its accuracy. The effects of various parameters such as grazing angle of the incident energy, receiver/ scatterer geometry, and the bottom half-space geoacoustic parameters are investigated numerically. The paper is concluded with a comparison of modeled time series with experimental scattering data obtained for a steel-shelled cylinder and a solid aluminum sphere lying on a sandy seabed.

Underwater bottom still mine classification using robust time–frequency feature and relevance vector machine

“…Some of the theory and implementation issues of modelling the backscattered energy from cylindrical or spherical objects lying on the seabed were described in [8]. The transmit linear frequency modulated (LFM) waveform is viewed as the complex bandpass function [18].…”

Diffraction of sound by a poroelastic cylindrical absorber near an impedance plane

“…To gain an understanding of the target-ground interaction affects, Dassios and Kleinman [23] develop a theory for lowfrequency scattering of 3D targets above a flat plane. Fawcett et al [24] utilized a single-scattering method to describe some of the theory and implementation issues of modeling the backscattered energy from cylindrical or spherical objects (shells) lying on a sandy seabed. Bishop and Smith [25] specialized the T-matrix approach to scattering from a planar boundary and generalized it to include scattering from rigid and soft spheres and finite cylinders with hemispherical endcaps and rigid, soft, fluid, viscoelastic and fluid-saturated poroelastic sediments.…”

Localization of Buried Objects in Sediment Using High Resolution Array Processing Methods

“…The bilinear focusing operator is used to decorrelate the signals (Valaee & Kabal, 1995) and to estimate the coherent signal subspace (Valaee & Kabal, 1995), (Wang & Kaveh, 1985). From the exact solution of the acoustic scattered field (Fawcett et al, 1998), (Junger, 1952), we have derived a new source steering vector including both the range and the bearing objects. This source steering vector is employed in MUSIC (MUltiple SIgnal Classification) algorithm (Valaee & Kabal, 1995) instead of the classical plane wave model.…”

“…• The exact solution of the acoustic scattering model has been addressed in many published work for several configurations, as single (Doolittle & Uberall, 1966), (Goodman & Stern, 1962) or multiple objects (Prada & Fink, 1998), (Zhen, 2001), buried or partially buried objects (Lim et al, 1993), (Tesei et al, 2002), with cylindrical (Doolittle & Uberall, 1966), (Junger, 1952), or spherical shape (Fawcett et al, 1998), (Goodman & Stern, 1962), (Junger, 1952),…”