Accession Number : ADA332353

Title :   Investigation of UWB Time-Domain Electromagnetic Phenomenology.

Descriptive Note : Final technical rept. 1 Jan 94-31 Dec 96,

Corporate Author : DUKE UNIV DURHAM NC

Personal Author(s) : Carin, Lawrence

PDF Url : ADA332353

Report Date : 08 NOV 1996

Pagination or Media Count : 5

Abstract : The research investigated under this grant has focused on the basic problem of time-domain electromagnetic scattering and propagation in various physical environments. An issue of particular importance has been dispersion, and how it is manifested in the time domain, Particular dispersive environments that have been investigated are periodic and quasi-periodic propagation and scattering, short-pulse propagation in lossy, dispersive soils. With regard to this latter topic, a significant problem of interest involved short-pulse electromagnetic scattering from buried targets, with a focus on buried mines. The research on short-pulse wave phenomenology has motivated a new research thrust, in which the underlying phenomenology is exploited in the development of what has been termed "wave-oriented" signal processing. Particular signal processing algorithms that have been investigated including the Gabor transform, the wavelet transform, and windowed superresolution processing. In this context, we have also performed sophisticated Cramer-Rao bound studies to assess the ultimate accuracy of such algorithms when the data is containunated with additive noise. Finally, the phenomenology is being exploited in the development of new wave-based time-frequency algorithms, in particular the wave-based methods of matched pursuits. This algorithm is very useful for the denoising of scattering data and is not being placed in the context of a decision-theoretic paradigm.

Descriptors :   *SIGNAL PROCESSING, *PROPAGATION, *ELECTROMAGNETIC SCATTERING, *TIME DOMAIN, *DISPERSIONS, ALGORITHMS, SCATTERING, ENVIRONMENTS, PHYSICAL PROPERTIES, ACCURACY, TARGETS, SOILS, ELECTROMAGNETISM, WAVES, SHORT PULSES, WAVELET TRANSFORMS.

Subject Categories : Physical Chemistry
      Miscellaneous Detection and Detectors
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE