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IEEE Transactions on Antennas and Propagation
Volume 46 Number 1, January 1998

Table of Contents for this issue

Complete paper in PDF format

Green's Function Refinement as an Approach to Radar Backscatter: General Theory and Applications to LGA Scattering from the Ocean

William T. Shaw and Andrew J. Dougan

Page 57.

Abstract:

We present a new approach to the computation of radar returns from dielectric bodies whose boundary is the deformation of a plane surface. The method relies on combining a systematic improvement in the Green's function with a good approximate choice of local boundary condition. In this paper, the general theory is presented together with a simple application where the Green's function is that for a lossy dielectric half-space. We derive the root radar cross section (RCS) for a statistical surface and the mean backscatter RCS for a rough surface. We explore the applications to low-grazing-angle (LGA) scattering from statistical surfaces with an ocean-like spectrum and demonstrate that such a model explains some of the previously unexplained LGA phenomena, such as the absolute and relative levels of the vertical (VV) and horizontal (HH) channel RCS measurements.

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