The PEC and PMC boundary conditions are the most straightforward to set up and use. Assigning the PEC boundary to one of the bounding walls of the solution domain simply forces the tangential component of the electric field to vanish at all points along that wall. Similarly, assigning the PMC boundary to one of the bounding walls of the solution domain forces the tangential component of the magnetic field to vanish at all points along that wall. For planar structures with a conductor-backed substrate, you can use the PEC boundary condition to designate the bottom of the substrate (the -Z Domain Wall) as a PEC ground. For shielded waveguide structures, you can designate all the lateral walls as PEC. Similarly to model shielded cavity resonators, you designate all the six walls as PEC.
===A Closer Look At In many electromagnetic modeling problems you need a boundary condition that simply absorbs all the incoming radiation. For problems of this nature, an absorbing boundary condition (ABC) is often chosen that effectively minimizes wave reflections at the boundary. EM.Tempo uses Convolutional Perfectly Matched Layers (CPML===) for absorbing boundary conditions. The boundary CPML cells in the project workspace are transparent to the user. But, in effect, multiple rows of CPML cells are placed on the exterior side of each face of the visible domain box.
{{mainpage|Click here to learn more about the theory of [[Advanced CPML SetupPerfectly Matched Layer Termination]]}}.
In many electromagnetic modeling problems you need a boundary that simply absorbs all the incoming radiationClick here to learn more about [[Advanced CPML Setup]]. For problems  You can also use EM.Tempo to model planar structures of this natureinfinite extents. To model a laterally infinite dielectric substrate, an absorbing you must assign a PML boundary condition (ABC) is often chosen that effectively minimizes wave reflections at to the boundary. The boundary ABC cells in four lateral sides of the project workspace are transparent to domain box and set the userlateral domain offset values along the ±X and ±Y directions all equal to zero. But, If the planar structure ends in effectan infinite dielectric half-space from the bottom, multiple rows of ABC cells are placed on you must assign a PML boundary condition to the exterior bottom side of each face of the visible domain boxand set the -Z offset equal to zero.
You may occasionally want to use [[EM.Cube]]'s FDTD simulator to model planar structures. Although [[EM.Cube]] provides the more computationally efficient [[Planar Module]] for this very purpose, there are many cases when an FDTD simulation might prove advantageous over a 2.5-D MoM simulation. To model a laterally infinite dielectric substrate, you must assign a PML boundary condition to the four lateral sides of the domain box and set the lateral domain offset values along the ±X and ±Y directions all equal to zero. If the planar structure ends in an infinite dielectric half-space from the bottom, you must assign a PML boundary condition to the bottom side of the domain box and set the -Z offset equal to zero.
== Generating the FDTD Mesh ==