Inverse obstacle scattering for homogeneous dielectric cylinders using a boundary finite-element method

A method for reconstructing the shape and the permittivity of a penetrable homogeneous cylinder is described. It is the extension to penetrable cylinders of a previous work dealing with perfectly conducting cylinders. A low-frequency approximation is used to determine an initial guess. Then, a rigorous boundary integral method permits us to reconstruct arbitrary shapes and complex permittivities. It is based on an iterative conjugate gradient algorithm requiring the solving of two direct diffraction problems only. A simple and original regularization scheme is presented, which ensures the robustness of the algorithm. Numerical examples with lossy embedding media and additional random noise for both E/spl par/ and H/spl par/ polarizations are given.

[1]  W. Rundell,et al.  Iterative methods for the reconstruction of an inverse potential problem , 1996 .

[2]  Roland Potthast,et al.  Frechet differentiability of boundary integral operators in inverse acoustic scattering , 1994 .

[3]  F. Hettlich Frechet derivatives in inverse obstacle scattering , 1995 .

[4]  A. Roger RECIPROCITY THEOREM APPLIED TO THE COMPUTATION OF FUNCTIONAL DERIVATIVES OF THE SCATTERING MATRIX , 1982 .

[5]  Chien-Ching Chiu,et al.  Electromagnetic imaging for an imperfectly conducting cylinder , 1991 .

[6]  Marc Saillard,et al.  Cross-borehole inverse scattering using a boundary finite-element method , 1998 .

[7]  D. Maystre,et al.  Diffraction d'une onde electromagnetique plane par un objet cylindrique non infiniment conducteur de section arbitraire , 1972 .

[8]  D. Colton,et al.  A simple method using Morozov's discrepancy principle for solving inverse scattering problems , 1997 .

[9]  T. Habashy,et al.  A two-step linear inversion of two-dimensional electrical conductivity , 1995 .

[10]  F. Santosa,et al.  Reconstruction of a two-dimensional binary obstacle by controlled evolution of a level-set , 1998 .

[11]  T. Habashy,et al.  Beyond the Born and Rytov approximations: A nonlinear approach to electromagnetic scattering , 1993 .

[12]  M. Fink Time reversed acoustics , 1997 .

[13]  Weng Cho Chew,et al.  Solution of the three-dimensional electromagnetic inverse problem by the local shape function and the conjugate gradient fast Fourier transform methods , 1997 .

[14]  Marc Saillard,et al.  Decomposition of the Time Reversal Operator for Electromagnetic Scattering , 1999 .

[15]  William Rundell,et al.  A quasi-Newton method in inverse obstacle scattering , 1994 .

[16]  Pierluigi Maponi,et al.  Three-dimensional time harmonic electromagnetic inverse scattering: The reconstruction of the shape and the impedance of an obstacle , 1996 .

[17]  T. Habashy,et al.  Rapid 2.5‐dimensional forward modeling and inversion via a new nonlinear scattering approximation , 1994 .

[18]  P. M. van den Berg,et al.  Two‐dimensional location and shape reconstruction , 1994 .

[19]  William H. Press,et al.  Numerical Recipes: FORTRAN , 1988 .

[20]  Gregory A. Newman,et al.  Crosswell electromagnetic inversion using integral and differential equations , 1995 .

[21]  P. M. Berg,et al.  A modified gradient method for two-dimensional problems in tomography , 1992 .

[22]  R. Kleinman,et al.  Microwave imaging-Location and shape reconstruction from multifrequency scattering data , 1997 .

[23]  A. Kirsch The domain derivative and two applications in inverse scattering theory , 1993 .

[24]  A. Roger Optimization of Perfectly Conducting Gratings a General Method , 1983 .