Modeling of waveguide structures using the nonorthogonal FDTD method with a PML absorbing boundary

Abstract

Abstract In this letter, we combine the nonorthogonal FDTD method with a perfectly matched layer (PML) absorbing boundary condition to analyze waveguide structures. This combination provides a very useful numerical tool for modeling complex waveguide structures. The PML absorbing boundary condition is tested by simulation of propagation in a WR‐75 rectangular waveguide. It easily gives lower than −60‐dB return loss in the frequency band of interest. An E‐plane, U‐bend waveguide transmission line is modeled to demonstrate the usefulness of this technique. © 1995 John Wiley & Sons. Inc.