ACCURATE COMPUTATION OF WIDE-BAND RESPONSE OF ELECTROMAGNETIC SYSTEMS UTILIZING NARROW-BAND INFORMATION

We investigate Cauchy's technique for interpolating a rational function from samples of frequency responses and/or their derivatives. This technique can be used to speed up the numerical computations of parameters including input impedance and RCS of any linear time-invariant electromagnetic system. Here we have applied the technique to find the electromagnetic response of a conducting cylinder over a spectrum of frequency. The numerical results presented are in good agreement with exact computational data. This technique is a true interpolation/extrapolation technique as it provides the same defective result as the original electric field integral equation at a frequency which corresponds to the internal resonance of the closed structure.