“Imaging Scenes with Acoustic and Electromagnetic Waves”

Thu Jun 13, 2019 2:00 PM

Location: LTS Auditorium, 8080 Greenmead Drive

Speaker:
Ramani Duraiswami
Professor, Department of Computer Science and UMIACS
(Joint work with Nail A. Gumerov, senior research scientist, UMIACS)

Abstract:
When waves (acoustic or electromagnetic) propagate from a source in an environment, the waves interact with objects in the environment. When these waves are sensed at a collection of spatially distributed receivers, a number of inverse problems can be considered for solution, including source-localization, source-separation, scene imaging, and others. The nature of interaction between waves and the environment is complex, and depends upon the ratio of the wavelength and object sizes in the environment. In the case of acoustics in spaces, the interactions provide a rich source of information about the source, the space and the objects in it.

Our group has been working on various aspects of 3-D audio—capture, analysis, modeling, rendering; and have spun some of this research out into a company, VisiSonics, to build hardware and software products based on this research. Some of this work will be described and demonstrated first.

Over the past few years, we have sought to extend the acoustical work to electromagnetic waves. Using modeling methods of mathematical physics we specialize the Maxwell equations to different cases based upon the wavelength and object sizes/material properties. Using the computationally efficient fast-multipole methods these derived equations can be solved in O(N) time and memory. The acoustic solvers have been parallelized onto heterogeneous CPU/GPU clusters. The codes allow computing accurate acoustical and electromagnetic scattering off arbitrary shape and objects.

We will describe some of these results, and discuss how the software and its future enhancements could be used for EM source separation, localization and imaging.

Speaker Bio:
Ramani Duraiswami is professor and associate chair at the Department of Computer Science with an appointment in UMIACS at the University of Maryland.

Duraiswami received his B. Tech. at IIT Bombay and his doctorate at Johns Hopkins University, both in mechanical engineering.

After spending a few years working in industry, he joined the University of Maryland, where he established the Perceptual Interfaces and Reality Lab.

Duraiswami has broad research interests, including spatial audio, computer vision, machine learning and scientific computing.

He has published more than 250 peer-reviewed archival papers, authored a book with Nail A. Gumerov, and has several issued patents.

Some of Duraiswami’s research has been spun out into a startup, VisiSonics.