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arXiv · 1911.06020

An Accelerated Nonlinear Contrast Source Inversion Scheme For Sparse Electromagnetic Imaging

Ali I. Sandhu·Abdulla Desmal·Hakan Bagci
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Abstract

An efficient nonlinear contrast source inversion scheme for electromagnetic imaging of sparse two-dimensional investigation domains is proposed. To avoid generating a sequence of linear sparse optimization problems, the non-linearity is directly tackled using the nonlinear Landweber (NLW) iterations. A self-adaptive projected accelerated steepest descent (A-PASD) algorithm is incorporated to enhance the efficiency of the NLW iterations. The algorithm enforces the sparsity constraint by projecting the result of each steepest descent iteration into the L1-norm ball and selects the largest-possible iteration step without sacrificing from convergence. Numerical results, which demonstrate the proposed schemes accuracy, efficiency, and applicability, are presented.

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Ali I. Sandhu, Abdulla Desmal, Hakan Bagci. 2019-11-14. An Accelerated Nonlinear Contrast Source Inversion Scheme For Sparse Electromagnetic Imaging. https://doi.org/10.1109/access.2021.3071397

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