Convolution PML (CPML): An efficient FDTD implementation of the CFS-PML for arbitrary media

A novel implementation of perfectly matched layer (PML) media is presented for the termination of FDTD lattices. The implementration is based on the s tretched coordinate form of the PML, a recursive convolution, and the USE O f complex frequency, shifted (CFS) PML parameters. The method, referred to here as the convolutional PML (CPML), offers a number of advantages over th e traditional implementations of the PML. Specifically, the application of the CPML is completely independent of the host,medium. Thus, no modificatio ns are necessary when applying it to inhomogeneous, lossy, anisotropic, dis persive, or nonlinear media. Secondly, it is shown that the CFS-PML is high ly absorptive of evanescent modes and can provide significant memory saving s when computing the wave interaction of elongated structures, sharp corner s, or low-frequency excitations. (C) 2000 John Wiley & Sons, Inc.