Accelerated PMM solutions via model-based parameter estimation and fast Fourier transform techniques

In this paper, an efficient spectral-domain PMM formulation is introduced for the accelerated analysis of large FSS problems. This PMM formulation incorporates the following techniques: (a) either a type of "smart" interpolation method known as model- based parameter estimation (MBPE) for efficient wide-band interpolation of the impedance matrices or an FFT-based method applied in calculating the impedance matrix elements, together with (b) an 0(N log N) FFT-based method for analyzing 3-D scattering problems, to speed up computation of the matrix-vector product within the iterative solver. The latter is possible due to the asymmetric multilevel block-Toeplitz structure [8] of the impedance-matrix that results from the uniform discretization of the FSS unit cell. Advantages of the proposed hybrid techniques are demonstrated through the presentation of several design examples.