Theoretical and Computational Aspects of Statistically Stable Adaptive Coherent Interferometric Imaging in Random Media

Tuesday, October 18, 2005 - 2:30pm - 3:20pm
EE/CS 3-180
Liliana Borcea (Rice University)
jointly with George Papanicolaou (Stanford) and Chrysoula Tsogka (U.

I will discuss a robust, coherent interferometric approach for array
imaging in cluttered media, in regimes with significant multipathing of
the waves by the inhomogeneities in clutter. In such scattering regimes,
the recorded traces at the array have long and noisy codas and classic
imaging methods give unstable results. Coherent interferometry is
essentially a very efficient statistical smoothing technique that exploits
systematically the spatial and temporal coherence in the data to obtain
stable images.

I will describe in some detail the resolution of this method for two types
of cluttered media: (1) isotropic, weakly scattering clutters, where waves
are scattered mostly forward and (2) layered, strongly fluctuating
clutters, where back scattering is strong. I will show that in spite of
such opposite wave scattering regimes, coherent interferometry behaves
equally well, which indicates its wide applicability.

In coherent interferometry, there is a delicate balance between having
stable and sharp images and achieving the optimal resolution depends on
our knowledge of the clutter dependent spatial and temporal decoherence
parameters. I will explain briefly how we can estimate these parameters
efficiently during the image formation process, as we do in
adaptive coherent interferometry.
MSC Code: