'Institute of Electrical and Electronics Engineers (IEEE)'
Doi
Abstract
A spectral-domain technique to solve the scattering
by perfectly conducting cylinders placed below a dielectric layer is
presented. Propagation fields are expressed in an analytic form, in
the frame of the cylindrical wave approach. The fields scattered by
the buried objects are decomposed into cylindrical waves, which
are, in turn, represented by plane-wave spectra. Due to the interaction
with a layered layout, the scattered fields experience multiple
infinite reflections at the boundaries of the layer. Using suitable
reflection and transmission coefficients inside the plane-wave
spectra, the interaction with such a layered geometry can be solved
with a single-reflection approach. Multiple reflections are collected
by a set of two scattered fields, i.e., an upward-propagating field,
excited by the scatterers and transmitted up to the top medium,
and a down-propagating one, which from the top medium reaches
the scatterers after transmission through the layer. Therefore, the
analytical theory is developed in a very compact way and can be
solved through a fast and efficient numerical implementation. Numerical
results are evaluated in an accurate way and validated by
comparisons with results obtained with a multiple-reflection approach.
The scattered field can be evaluated in any point of the domain,
in the far-field as well as the near-field region. Two-dimensional
maps displaying the magnitude of the total scattered field
are reported, showing examples of applications of the technique