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.
[[Image:Info_icon.png|40px]] Click here to learn more about the theory of '''[[Perfectly_Matched_Layer_TerminationBasic_FDTD_Theory#The_CPML_Formulation Why_Does_FDTD_Need_Domain_Termination.3F | Perfectly Matched Layer Termination]]'''.
[[Image:Info_icon.png|40px]] Click here to learn more about '''[[Perfectly_Matched_Layer_Termination#Advanced_CMPL_Setup | Advanced CPML Setup]]'''.