Efficient Wideband Computation of Electromagnetic Scattering by Finite Periodic Structures Combining ASED Basis Function With Frequency-Independent Reaction

Abstract

An efficient wideband electromagnetic scattering analysis method for finite periodic structures by combining the accurate subentire-domain (ASED) basis function with the frequency-independent reaction (FIR) is presented. The ASED basis function is suitable for analyzing finite periodic structures with less unknowns than the conventional method of moments (MoM). Its efficiency is very high. However, it is a single-frequency technique and is still time-consuming for frequency sweep. The FIR can accelerate the frequency sweep, in which the exponential of the Green function is expanded in Taylor series. The impedance element is formulated as the sum of the series, where each term is the product of the geometry-dependent element and the phase factor. Recomputation of the former one is unnecessary during frequency sweep. Thus, it is very efficient. To test the accuracy of the proposed algorithm, several examples are implemented. Numerical results show that the results obtained using the proposed method agree well with those computed using the ASED basis function and conventional MoM. The efficiency of the proposed technique is also validated.