Fast scattering analysis over a wide frequency band using Clenshaw-Lord-type Pade-Chebyshev approximation

Pade-Chebyshev approximation of Clenshaw-Lord type with method of moments is proposed for wide-band analysis of an arbitrary-shaped perfect electric conductor structure. Moreover, various Chebyshev polynomials, such as first, third, and fourth kinds, are used to express the singular points in the graph to display the expected result for scattering characteristics. The proposed algorithm has a wide radius of convergence due to the use of Chebyshev polynomials and improves calculation speed because Clenshaw-Lord-type Pade approximation requires fewer sampling points than Maehly-type Pade approximation in the derivation of the rational function. The results of the proposed method agree very well with the exact solution and reveal its possibility of obtaining more accurate solution than the asymptotic waveform evaluation technique.