Efficient Frequency Sweep Technique for Analysis of Array With Identical Modules

Abstract

To realize efficient frequency sweep for analysis of periodic arrays, the generalized transition matrix (GTM) method is adopted combining with the cubic Lagrange interpolation scheme in this letter. Utilizing an appropriate reference surface to wrap each module of periodic arrays, the GTM can be constructed to extract the scattering characteristics of the internal scatterer by multiplying three matrices accounting for the inward/outward transferring process and the scattering of the internal structure. In order to achieve efficient and accurate broad band sweep, the cubic Lagrange interpolation scheme is not applied directly to the GTM but separately to its three factor matrices and the field transmission matrices. The synthetic basis functions (SBFs) are established on the reference surface to reduce significantly the computational cost and the number of unknowns. The GTM in the interpolated forms and SBFs can be reused for all modules. Numerical examples show high accuracy and efficiency of the proposed method.