* [[Planar_MoM_Source_Types#Probe_Sources|Probe Sources]]
* [[Planar_MoM_Source_Types#De-Embedded_Sources|De-embedded Sources]]
* [[Planar_MoM_Source_TypesCommon_Excitation_Source_Types_in_EM.Cube#Short_Dipole_SourcesHertzian_Dipole_Sources |Short Dipole Sources]]* [[Planar_MoM_Source_TypesCommon_Excitation_Source_Types_in_EM.Cube#Plane_Wave_Sources|Plane Wave Sources]]* [[Hybrid_Modeling_using_Multiple_Simulation_Engines#Huygens SourcesWorking_with_Huygens_Sources |Huygens Sources]]
For antennas and planar circuits, where you typically define one or more ports, you usually use lumped sources. A lumped source is indeed a gap discontinuity that is placed on the path of an electric or magnetic current flow, where a voltage or current source is connected to inject a signal. Gap sources are placed across metal or slot traces. Probe sources are placed across vertical PEC vias. A de-embedded source is a special type of gap source that is placed near the open end of an elongated metal or slot trace to create a standing wave pattern, from which the scattering [[parameters]] can be calculated accurately. To calculate the scattering characteristics of a planar structure, e.g. its radar cross section (RCS), you excite it with a plane wave source. Short dipole sources are used to explore propagation of points sources along a layered structure. Huygens sources are virtual equivalent sources that capture the radiated electric and magnetic fields from another structure possibly in another [[EM.Cube]] computational module and bring them as a new source to excite your planar structure.