Before you can run an FDTD simulation, you have to define a source to excite your projectâs physical structure. EM.Tempo offers a variety of excitation mechanisms for your physical structure depending on your particular type of modeling problem or application:
# '''[[FDTD_Source_TypesCommon_Excitation_Source_Types_in_EM.Cube#Lumped_SourceLumped_.26_Gap_Sources|Lumped Source]]''': An ideal source that must be place on a wire (a PEC line object).# '''[[FDTD_Source_TypesCommon_Excitation_Source_Types_in_EM.Cube#Distributed_SourceDistributed_Sources |Distributed SourceSources]]''': A source with a prescribed impressed field component that is defined on a rectangular region of space parallel to a principal plane.# '''[[FDTD_Source_TypesCommon_Excitation_Source_Types_in_EM.Cube#Waveguide_SourceWaveguide_Sources |Waveguide SourceSources]]''': A distributed source that must be placed across a hollow PEC box object.# '''[[FDTD_Source_TypesCommon_Excitation_Source_Types_in_EM.Cube#Plane_Wave_SourcePlane_Wave_Sources |Plane Wave Source]]''': A distributed source with a plane wave profile defined using a virtual box object enclosing the entire physical structure. # '''[[FDTD_Source_TypesCommon_Excitation_Source_Types_in_EM.Cube#Gaussian_Beam_SourceGaussian_Beam_Sources |Gaussian Beam Source]]''': A distributed source with a complex-valued focused Gaussian beam profile defined using a virtual box object enclosing the entire physical structure.
A lumped source is the most commonly used way of exciting a structure in EM.Tempo. A lumped source is an ideal source that must be placed on a line object that is parallel to one of the three principal axes and shows up as a small red arrow on the host line. Lumped sources are typically used to define ports and compute the port characteristics like S/Y/Z [[parameters]].