Uniform theory for the diffraction of evanescent plane waves

Area of Science:

• Electromagnetics and Optics
• Wave Diffraction Theory

Background:

• The Fresnel integral is a fundamental tool for analyzing diffraction phenomena.
• Calculating uniform diffracted fields, especially for inhomogeneous waves, presents challenges.

Purpose of the Study:

• To introduce a novel method for obtaining uniform diffracted fields using Fresnel functions.
• To apply this method to the diffraction of inhomogeneous plane waves by canonical structures.

Main Methods:

• The core method involves subtracting the unit step function from the Fresnel integral.
• This technique is applied to analyze diffraction by a perfectly conducting half-plane and wedge.
• Numerical plotting and comparison with existing literature data are used for validation.

Main Results:

• A uniform diffracted field solution is derived in terms of Fresnel functions with complex arguments.
• The method successfully models the diffraction of inhomogeneous plane waves.
• Numerical results align with previously reported data, confirming the method's validity.

Conclusions:

• The proposed subtraction method offers an effective way to compute uniform diffracted fields.
• This technique enhances the analysis of inhomogeneous plane wave diffraction problems.
• The findings provide a valuable tool for electromagnetic wave propagation studies.