Hybrid Technique of Fast RCS Computation With Characteristic Modes and AWE

The technique to integrate the characteristic modes (CMs) with the asymptotic waveform evaluation (AWE) is proposed for computing the radar cross section (RCS) of an arbitrarily shaped three-dimensional perfect electric conductor (PEC). In the analysis, a few CMs with smaller eigenvalues are chosen to construct the subspace of the solution of a matrix equation. Hence, the solution of the equation can be obtained by combining the based-vectors of the subspace with a set of coefficients, which can be determined by the AWE technique at a given frequency. In addition, the criterion of the spectral radius is found in order that the subspace can be adaptively constructed. Finally, the results of numerical examples prove that the novel technique with CMs and AWE (CMAWE) is effective in widening the extrapolation range.