A new two-dimensional (2-D) transmission-line matrix (TLM) node for th
e modeling of perfectly matched layer (PML) media is presented. A rigo
rous field formulation of the 2-D TLM node allows one to construct a n
ode that has a scattering matrix fully compatible with the standard 2-
D hybrid node. This approach avoids the coupling of the TLM algorithm
with a finite difference time-domain (FDTD) approximation of PML field
differential equations. The simulation of a wideband matched load for
a WR-28 rectangular waveguide is presented for validation. A return l
oss better than 60 dB is obtained over the 25-40 GHz-frequency band.