The Method of Ordered Multiple Interactions provides a numerical solution to the integral<br />equations describing surface scattering which is both computationally efficient and reliably<br />convergent. The method has been applied in a variety of ways to solving the electromagnetic<br />scattering from perfectly-conducting rough surfaces. A desire to more accurately predict<br />the scattering from natural terrain has led to the representation of the surface material as<br />penetrable instead of conductive.<br /><br />For this purpose, the Method of Ordered Multiple Interactions is applied to numerically<br />solve the electromagnetic scattering from randomly-rough dielectric surfaces. A primary<br />consequence of the penetrable surface material is the introduction of a pair of coupled integral equations in place of the single integral equation used to solve the problem with a perfectly conducting surface. The method is tested and analyzed by developing independent scattering solutions for canonical cases in a transform domain and by comparing results with solutions from other techniques.<br /><br />The dielectric implementation of the Method of Ordered Multiple Interactions is used to solve<br />the electromagnetic scattering from a class of randomly-rough dielectric surfaces. This allows<br />for the characterization of the effect of a number of transmitter and surface parameters in the<br />scattering problem, observing bistatically and also specifically in the backscatter direction.<br /><br />MOMI is then applied as a method to examine subsurface penetration characteristics from<br />a similar family of rough surfaces. Characteristics of the environment parameters and the<br />scattered field itself are examined, and the numerical challenges associated with observing<br />beneath the surface are identified and addressed.<br /><br />The Method of Ordered Multiple Interactions is then incorporated as a major component of<br />a larger solution which computes the total scattering when a dielectric object is buried just<br />beneath the rough surface. This hyrid approach uses MOMI and the Method of Moments to<br />iteratively account for multiple interactions between the target and the dielectric interface,<br />enabling the study of scattering from the combined environment of a rough surface and the<br />embedded object, as well as the individual scattering events which combine to form the<br />steady-state solution. / Ph. D.
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/19346 |
| Date | 24 April 2013 |
| Creators | Westin, Benjamin Alexander |
| Contributors | Electrical and Computer Engineering, Brown, Gary S., Kohler, Werner E., Davis, William A., Scales, Wayne A., Guido, Louis J. |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Detected Language | English |
| Type | Dissertation |
| Format | ETD, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
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