Broadside radar cross section of the perfectly conducting cube

The broadside radar cross section (RCS) of the perfectly conducting cube is predicted from arbitrarily low to arbitrarily high frequencies, and compared to measured data taken for cube side lengths ranging from 0.15 to 4 wavelengths. The predicted and measured RCS curves agree to within the estimated experimental limits of accuracy of + or 1 dB. At low frequencies the magnetic-field integral equation was 'augmented' to eliminate its spurious homogeneous solutions and thus to produce high accuracy beyond the resonance region up through the intermediate frequency range. At high frequencies the conventional diffraction solution was 'enhanced' to produce high accuracy down through the intermediate frequency range into the resonance region. Close agreement between these two very different theoretical solutions in the intermediate frequency range confirmed the validity of each solution and permitted calculation of reliable curves for the amplitude and phase of the backscattered far field versus frequency.