|-
| style="width:30px;" | [[File:gap_src_icon.png]]
| [[Glossary of EM.Cube's Excitation Materials, Sources, Devices & Other Physical Object Types#Strip Gap Circuit Source |Strip Gap Circuit Source]]
| style="width:300px;" | General-purpose point voltage source
| style="width:300px;" | Associated with a PEC rectangle strip, works only with SMOM solver
|-
| style="width:30px;" | [[File:gap_src_icon.png]]
| [[Glossary of EM.Cube's Excitation Materials, Sources, Devices & Other Physical Object Types#Wire Gap Circuit Source |Wire Gap Circuit Source]]
| style="width:300px;" | General-purpose point voltage source
| style="width:300px;" | Associated with an PEC or thin wire line or polyline, works only with WMOM solver
|-
| style="width:30px;" | [[File:hertz_src_icon.png]]
| [[Glossary of EM.Cube's Excitation Materials, Sources, Devices & Other Physical Object Types#Hertzian Short Dipole Source |Hertzian Short Dipole Source]]
| style="width:300px;" | Almost omni-directional physical radiator
| style="width:300px;" | None, stand-alone source
|-
| style="width:30px;" | [[File:plane_wave_icon.png]]
| [[Glossary of EM.Cube's Excitation Materials, Sources, Devices & Other Physical Object Types#Plane Wave |Plane Wave Source]]
| style="width:300px;" | Used for modeling scattering
| style="width:300px;" | None, stand-alone source
|-
| style="width:30px;" | [[File:huyg_src_icon.png]]
| [[Glossary of EM.Cube's Excitation Materials, Sources, Devices & Other Physical Object Types#Huygens Source |Huygens Source]]
| style="width:300px;" | Used for modeling equivalent sourced imported from other [[EM.Cube]] modules
| style="width:300px;" | Imported from a Huygens surface data file
|}
Click on each category to learn more details about it in the [[Glossary of EM.Cube's Excitation Materials, Sources, Devices & Other Physical Object Types]].
For antennas and planar circuits, where you typically define one or more ports, you usually use lumped sources. [[EM.Libera]] provides two types of lumped sources: strip gap and wire gap. A Gap is an infinitesimally narrow discontinuity that is placed on the path of the current and is used to define an ideal voltage source. Wire gap sources must be placed on '''Thin Wire Line''' and '''Thin Polyline''' objects to provide excitation for the Wire MoM solver. The gap splits the wire into two lines with a an infinitesimally small spacing between them, across which the ideal voltage source is connected.