Electro-acoustic Scattering from a Pulsating Sphere

TL;DR

This paper investigates how acoustic disturbances cause dielectric inhomogeneities around a pulsating sphere, leading to RCS enhancement and detectable Bragg scattering, even without direct object scattering.

Contribution

It introduces a model for acoustic-induced dielectric variations and demonstrates RCS enhancement and Bragg scattering detection using FDTD simulations.

Findings

Dielectric variations due to acoustic sources can be detected without object scattering.

Acoustic disturbances significantly increase RCS through dielectric inhomogeneities.

Bragg scattering occurs along with RCS enhancement in pulsating dielectric objects.

Abstract

In this paper, we show the RCS enhancement due to the acoustic disturbances around a pulsating sphere. The acoustic variation is modeled with the dielectric inhomogeneities around the sphere caused by the pressure fluctuations due to the acoustic source. RCS is computed for the modeled dielectric pulsating sphere, a cube, and a cone on a cylinder across a frequency band using Finite Difference Time Domain (FDTD) method. The RCS of the pulsating sphere and other objects considered are dominated by the background scattering from the pulsating object. In this work, we show that the dielectric variation due to the acoustic source can be detected even if there is no scattering from the object. The scattering from the dielectric variation leads to the detection of Bragg scattering along with a significant increase in RCS.