An Efficient Preconditioned MLFMA for Accurate Analysis of Electromagnetic Radiation Problems with Waveport

In this paper, a preconditioned multilevel fast multipole algorithm (MLFMA) is presented for calculating the radiation characteristics of electrically large antenna-radome systems. The waveport model of MLFMA is established based on the equivalence principle and mode matching theory, which is proposed for calculating metal-dielectric antenna models. A preconditioner is designed for MLFMA to improve the convergence when calculating the radiation problems with waveports. Numerical results are presented to demonstrate that the proposed MLFMA can efficiently and accurately calculate the radiation characteristics of antenna-radome systems.