Moving Structures in a 3D FDTD Code

This paper introduces a method that combines the finite-difference time-domain (FDTD) technique with a direct modeling approach to study electromagnetic field diffraction from moving 3D structures. By updating object positions after a specified number of time steps within the FDTD time-stepping loop, the method effectively models motion. Comprehensive descriptions of the theoretical foundation and algorithm are included. The method's effectiveness is illustrated through a case study involving the diffraction response of a moving metallic sphere illuminated by a line source.