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  • Research Article
  • Open Access

Subspace-Based Localization and Inverse Scattering of Multiply Scattering Point Targets

EURASIP Journal on Advances in Signal Processing20062007:017342

  • Received: 15 September 2005
  • Accepted: 12 May 2006
  • Published:


The nonlinear inverse scattering problem of estimating the locations and scattering strengths or reflectivities of a number of small, point-like inhomogeneities (targets) to a known background medium from single-snapshot active wave sensor array data is investigated in connection with time-reversal multiple signal classification and an alternative signal subspace method which is based on search in high-dimensional parameter space and which is found to outperform the time-reversal approach in number of localizable targets and in estimation variance. A noniterative formula for the calculation of the target reflectivities is derived which completes the solution of the nonlinear inverse scattering problem for the general case when there is significant multiple scattering between the targets. The paper includes computer simulations illustrating the theory and methods discussed in the paper.


  • Point Target
  • Sensor Array
  • Inverse Scattering
  • Subspace Method
  • Background Medium

Authors’ Affiliations

Department of Electrical and Computer Engineering, Center for Subsurface Sensing and Imaging Systems, and Communications and Digital Signal Processing Center for Research and Graduate Studies, Northeastern University, Boston, MA 02115, USA
Department of Electrical and Computer Engineering, Northeastern University, Boston, MA 02115, USA


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© E. A. Marengo and F. K. Gruber. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.