Scattering of targets over layered half space using a semi-analytic method in conjunction with FDTD algorithm

Area of Science:

• Computational electromagnetics
• Numerical analysis

Background:

• Traditional plane wave excitation methods for radar cross section (RCS) calculations using finite-difference time-domain (FDTD) algorithms are computationally intensive.
• Evaluating half-space Green functions is a complex and time-consuming step in existing FDTD extrapolation methods for far-field RCS.

Purpose of the Study:

• To develop a novel, computationally efficient FDTD method for analyzing RCS characteristics of targets situated over layered half spaces.
• To circumvent the need for complex half-space Green function evaluations in RCS calculations.

Main Methods:

• Implementation of a new plane wave excitation technique within the FDTD algorithm.
• Extrapolation of near-field data on the output boundary to obtain far-field RCS.
• Development of a novel extrapolation method that bypasses the evaluation of half-space Green functions.

Main Results:

• The proposed method demonstrates a significant reduction in calculation memory and time requirements compared to traditional approaches.
• Numerical results show excellent agreement between the new method and classic algorithms.
• The new method is validated for fast calculation of scattering and radiation from targets over layered half spaces.

Conclusions:

• The novel FDTD method offers a computationally efficient alternative for RCS analysis of targets over layered media.
• This approach simplifies the calculation process by eliminating the need for complex Green function evaluations.
• The method is suitable for rapid electromagnetic scattering and radiation simulations in geophysics and defense applications.