P. Lobel et al., CONJUGATE-GRADIENT METHOD FOR SOLVING INVERSE SCATTERING WITH EXPERIMENTAL-DATA, IEEE antennas & propagation magazine, 38(3), 1996, pp. 48-51
The reconstruct of the complex permittivity profile of lossy dielectri
c objects from measured far-field data is considered, with application
to perfectly conducting (PEG) objects. From an integral representatio
n of the electric field (EFIE), and applying a moment-method solution,
an iterative-reconstruction algorithm based on a conjugate-gradient m
ethod, is derived. In order to start the iterative procedure with an i
nitial guess, a back-propagation scheme is used. For testing the algor
ithm on real, measured data, the reconstruction of two PEC (cylinder a
nd strip) objects is presented.