An optimized anisotropic PML for the analysis of microwave circuits

The anisotropic perfectly matched layer (PML) is implemented in the finite-element method (FEM) to evaluate the S-parameters of microwave integrated circuits (MIC's). The PML region, which terminates the mesh over a range of frequencies, may exhibit either a uniform or nonuniform conductivity profile /spl sigma/(/spl rho/). The performance of the PML is strongly dependent on the choice of /spl sigma/(/spl rho/) as well as the mesh density inside the absorber. This observation is demonstrated numerically using a two-dimensional (2-D) finite-element analysis. The anisotropic PML is subsequently used in modeling three-dimensional (3-D) microwave integrated circuits. The accuracy and overall performance of the absorber is evaluated by computing the S-parameters of a low-pass filter.