New Accurate Subentire-Domain Basis Functions Method for the Analysis of Large-Scale Finite Periodic Structures with Electrically Connected Cells

Abstract

Accurate subentire-domain (ASED) basis functions method have been proved efficient for solving large-scale finite periodic structures (LFPSs) with electrically isolated elements, based on utilizing ASED basis functions. These basis functions, defined on macrodomains (blocks) including a relatively large number of Rao–Wilton–Glisson (RWG) basis functions, lead to a great reduction in the number of the unknowns and result in the substantial size reduction of the original method of moment matrix. However, the ASED basis functions method cannot obtain an accurate analysis of the LFPSs with electrically connected cells. In this communication, a new ASED basis functions method, based on the ASED basis functions, is proposed to solve the electromagnetic scattering problem of the LFPSs with electrically connected cells. In the new method, the multiple plane waves are employed to excite the $3\times 3$ array and construct more ASED basis functions. Due to the intrinsic continuity of the first $3\times 3$ array problem, the new ASED basis functions method do not request any overlap between adjacent unit cells, or any “connection” basis functions. In addition, the new ASED basis functions method merges the advantage of the multiple PWs on the efficient computation of monostatic radar cross section (RCS). Numerical examples are given to prove the accuracy and efficiency of the new ASED basis functions method including the computation of both bistatic and monostatic RCSs.