Computational Analysis of 2D Electromagnetic Scattering with Near-Far Field Transformation

The fd1.rar package provides computational tools for analyzing two-dimensional electromagnetic scattering phenomena and performing near-field to far-field transformations, enabling accurate radar cross-section calculations. This implementation utilizes the finite-difference time-domain (FDTD) method, which discretizes Maxwell's equations in both space and time domains to simulate electromagnetic wave interactions with target objects. The core algorithm operates by dividing the computational domain into a Yee grid structure, where electric and magnetic field components are staggered in space and time. Key functions include boundary condition handling (typically using perfectly matched layers), source excitation mechanisms, and near-field data collection routines. The near-to-far-field transformation module employs surface equivalence principles to project near-field data to the far-field region, facilitating RCS computation through appropriate integration techniques. This tool enables researchers to thoroughly investigate electromagnetic scattering behavior and obtain precise radar cross-section data, supporting applications in radar system design, stealth technology assessment, and electromagnetic compatibility analysis. The implementation includes visualization capabilities for field distribution patterns and RCS diagrams across different frequency ranges and observation angles.