title: Wideband time-reversal imaging of an elastic target in an acoustic waveguide.
abstract: Time-reversal is addressed for imaging elastic targets situated in an acoustic waveguide. It is assumed that the target-sensor range is large relative to the channel depth. We investigate the theory of wideband time-reversal imaging of an extended elastic target, for which the target dimensions are large relative to the principal wavelengths. When performing time-reversal imaging one requires a forward model for propagation through the channel, and the quality of the resulting image may be used as a measure of the match between the modeled and actual (measured) channel parameters. It is demonstrated that the channel parameters associated with a given measurement may be determined via a genetic-algorithm (GA) search in parameter space, employing a cost function based on the time-reversal image quality. Example GA channel-parameter-inversion results and imagery are presented for measured at-sea data.
authors.affiliation: Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708-0291, USA. lcarin@ee.duke.edu
authors.forename: Lawrence
authors.initials: L
authors.lastname: Carin
authors.forename: Hongwei
authors.initials: H
authors.lastname: Liu
authors.forename: Timothy
authors.initials: T
authors.lastname: Yoder
authors.forename: Luise
authors.initials: L
authors.lastname: Couchman
authors.forename: Brian
authors.initials: B
authors.lastname: Houston
authors.forename: Joseph
authors.initials: J
authors.lastname: Bucaro