A fast frequency sweeping method for RCS computation based on the rational interpolation technique

The method of moments (MoM) in conjunction with the rational interpolation (RI) technique is applied to predict the radar cross section (RCS) of an arbitrarily shaped 2D perfect electric conductor (PEC) cylinder over a frequency band. The electric field integral equation (EFIE) of a 2D PEC cylinder is solved using MoM to obtain the equivalent surface current on the PEC cylinder in a sequence of frequencies. In the RI technique, the equivalent surface current in the desired frequency is expanded in the rational function. The rational function coefficients are then obtained via the interpolation technique. Using the rational function, the surface current is obtained at any frequency within the frequency range, which is in turn used to calculate RCS of the 2D PEC cylinder. It was observed that RI technique could result in considerable CPU time saving.