Speaker: Altaf Khan

Title: Extended Contrast Source Inversion(ECSI) Algorithm in Scattering Problem( Kleinman and van den Berg)

Abstract

Ultrasound tomography is a new imaging modality, and is capable of producing images with high spatial and temporal resolution. Most of the commonly techniques available for the solution of Lippmann-Schwinger for the forward model is CG-FFT methods. The crux of the problem in the ultrasound tomography is the inversion of forward model for the determination of the shape, location and index of refraction of an inhomogeneity embedded in a homogeneous background medium from the measurement of the field scattered by the object when illuminated by known incident electromagnetic waves. Almost all of the techniques involve iterative minimization of a cost functional, e.g., Newton type method requires the solution of a direct scattering problem at each iterative step, while others avoid the repeated use of a direct method. This algorithm (ECSI) also utilizes the techniques of an iterative minimization of a cost functional but does not require the repeated use of the direct problem at each iterative step.