In
numerical analysis
Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic computation, symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of ...
, the uniform theory of diffraction (UTD) is a
high-frequency
High frequency (HF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) between 3 and 30 megahertz (MHz). It is also known as the decameter band or decameter wave as its wavelengths range from one to ten ...
method for solving
electromagnetic
In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of a ...
scattering
Scattering is a term used in physics to describe a wide range of physical processes where moving particles or radiation of some form, such as light or sound, are forced to deviate from a straight trajectory by localized non-uniformities (including ...
problems from electrically small discontinuities or discontinuities in more than one dimension at the same point. UTD is an extension of
Joseph Keller
Joseph Bishop Keller (July 31, 1923 – September 7, 2016) was an American mathematician who specialized in applied mathematics. He was best known for his work on the "geometrical theory of diffraction" (GTD).
Early life and education
Born i ...
's geometrical theory of diffraction (GTD).
[ J. B. Keller]
"Geometrical theory of diffraction"
''J. Opt. Soc. Am.'', vol. 52, no. 2, pp. 116–130, 1962.
The uniform theory of diffraction approximates
near field electromagnetic fields as
quasi optical and uses
knife-edge diffraction to determine diffraction coefficients for each diffracting object-source combination. These coefficients are then used to calculate the field strength and
phase
Phase or phases may refer to:
Science
*State of matter, or phase, one of the distinct forms in which matter can exist
*Phase (matter), a region of space throughout which all physical properties are essentially uniform
* Phase space, a mathematic ...
for each direction away from the diffracting point.
These fields are then added to the incident fields and reflected fields to obtain a total solution.
See also
*
Electromagnetic modeling
Computational electromagnetics (CEM), computational electrodynamics or electromagnetic modeling is the process of modeling the interaction of electromagnetic fields with physical objects and the environment.
It typically involves using computer ...
*
Biot–Tolstoy–Medwin diffraction model
References
External links
Overview of Asymptotic Expansion Methods in Electromagnetics
Numerical differential equations
Computational electromagnetics
Diffraction
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