PROGRESS IN ELECTROMAGNETICS RESEARCH-PIER, vol.108, pp.81-99, 2010 (SCI-Expanded)
We present fast and accurate sloutions of electromagnetics problems involving realistic metamaterial structures using a lowfrequency multilevel fast multipole algorithm (LF-MLFMA). Accelerating iterative solutions using robust preconditioning techniques may not be sufficient to reduce the overall processing time when the ordinary high-frequency MLFMA is applied to metamaterial problems. The major bottleneck, i.e., the low-frequency breakdown, should be eliminated for efficient sloutions. We show that the combination of an LF-MLFMA implmentation, we demonstrate how the transmission properties of metamaterial walls can be enhanced with randomly-oriented unit cells.