A Novel Periodic Characteristic Mode Analysis Method for Large-Scale Finite Arrays

A novel technique, namely periodic characteristic mode (CM) analysis (PCMA) method, is proposed for the solution of CMs of large-scale finite periodic arrays. This technique first adopts a small set of CMs of the reference element of the array with larger modal significance (MS) to construct the entire-domain basis functions defined on each array element and then applies them to expand the characteristic currents of the entire array. By using these newly constructed CM-based entire-domain basis functions, the proposed PCMA method can achieve great reduction in the matrix dimension of the resultant generalized eigenvalue problem governed by the entire array structure, thereby significantly reducing the computational time and memory requirement for solving CMs of the entire large-scale finite periodic array. Several typical examples are presented to demonstrate the efficiency and accuracy of the proposed method.