Complete Bistatic (4 Pi) Polarimetric Characterization of Waves Scattered from and across TwoDimensional Random Rough Surfaces Using the Full Wave Approach.
Abstract
In this work, the full wave approach (Bahar, 1981a, 1991; Bahar and Lee, 1994a, 1995a) is used to obtain the expressions for the scatter cross sections for twodimensional random rough surfaces. Formally, it involves 10dimensional integrals. Under certain justifiable conditions, this expression can be reduced to a tractable form. This work is strictly restricted to rough surfaces with large radii of curvature compared to wavelength. The limitations of the generalized full wave solutions that have been recently cited in the technical literature (Thompson and Chapman, 1993; Collin, 1994) are not addressed in this work. The large radii of curvature restriction is introduced in order to reduce to three, the dimension of the multiple integrals used to compute the cross sections for two dimensional rough surfaces. If, in addition to the large radii of surface curvature assumption, the rough surface is homogeneous and isotropic, the 10dimensional integral can be expressed as a 3dimensional integral. This integral accounts for the surface height/slope correlation through the use of the conditional joint characteristic functions (Bahar, 1991; Bahar and Lee, 1994a). This full wave solution is shown to reduce to the small perturbation solution (Rice, 1951) and reduce to the physical optics solution (Beckmann and Spizzichino, 1963) in their appropriate regions of validity. The full wave results are compared with the associated small perturbation and physical/geometrical optics results as well as the experimental (O'Donell and Mendez, 1987) and numerical (SanchezGil and NietoVesperinas, 1991) results. The scattering cross sections are the top left 2 x 2 elements of the modified Mueller matrix. The Mueller matrix elements are related to the like and cross polarized radar cross sections as well as to the relative phase of the vertically and horizontally polarized waves. The 4 x 4 Mueller matrix completely characterizes the scattered fields from the target. These Mueller matrix elements are evaluated using the full wave approach for a complete bistatic polarimetric characterization of waves scattered from twodimensional random rough surfaces. The various features of the Mueller matrix elements may be used as a guide for the identification of rough surface characteristics.
 Publication:

Ph.D. Thesis
 Pub Date:
 January 1995
 Bibcode:
 1995PhDT........98L
 Keywords:

 Engineering: Electronics and Electrical; Physics: Optics; Physics: Atmospheric Science; Remote Sensing