Application of Several Preconditions in Characteristic Modes Method

When the characteristic modes (CMs) method is used to analyze the repetitive structures, different structures have different convergence characteristics during iterative solution. The reduced matrix produced by CMs is a dense matrix. For the reduced matrices with poor behavior, the iterative algorithm converges very slowly or even does not. Aiming at this problem, this paper studies the application of typical preconditioning techniques in the CMs method. The numerical example in this paper fully proves the effectiveness of preconditioning techniques in accelerating the iterative convergence.