Scattering from a rectangular cavity using FDTD

Abstract

Far zone backscatter from a perfectly conducting rectangular cavity with one open end has been measured. The cavity is 2.5 /spl times/ 2.5 /spl times/ 3.75 inches, with one of the 2.5 /spl times/ 2.5 inch square ends open. Wide-frequency bandwidth backscatter measurements were made at 0/spl deg/ incidence (directly into the opening of the cavity), 33.5/spl deg/, and 53.5/spl deg/ for both polarizations. Calculations of the radar cross section (RCS) of the cavity were made using a finite difference time domain (FDTD) computer code, which uses a scattered field formulation for the FDTD calculations with linear time differencing. Example results are shown, including the time-domain far-zone backscattered electric field, and the corresponding scattering cross section compared with measured results. >