Implementation of Perfectly Matched Layer (PML) for the WCS-FDTD Method Using DSP Techniques

An efficient implementation of perfectly matched layer (PML), based on the stretched coordinate PML (SC-PML) and digital signal processing (DSP) techniques, is proposed to truncate the weakly conditional stable finite-difference time-domain (WCS-FDTD) lattices. The updating PML equations are further simplified with the introduction of auxiliary quantities. Compared to the convolutional PML (CPML), the proposed PML achieves better absorbing performance at the same computational expenditure. With its implementation, energy leakage from small cross-slots of a rectangular waveguide coupler is predicted accurately, which agrees very well with that of the other methods.