=== Modeling Lumped Circuits ===
[[File:wire_pic15.png|thumb|300px|[[MoM3D Module]]'s lumped element dialog]]
In EM.Cube's [[MoM3D Module]], you can define simple lumped elements in a similar manner as gap sources. In fact, a lumped element is equivalent to an infinitesimally narrow gap that is placed in the path of the current, across which Ohm's law is enforced as a boundary condition. You can define passive RLC lumped elements or active lumped elements containing a voltage gap source. The latter case can be used to excite a wire structure and model a non-ideal voltage source with an internal resistance. Unlike the [[FDTD Module]]'s single-device lumped loads that connect between two adjacent nodes, the [[MoM3D Module]]'s lumped circuit represent a series-parallel combination of resistor, inductor and capacitor elements. This is shown in the figure below:
[[File:image106.png]]
[[File:wire_pic16_tn.png|thumb|200px|Active lumped element with a voltage gap in series with an RC circuit placed on a dipole wire]]
To define a new lumped element, follow these steps:
* If the lumped element is active and contains a gap source, the '''Source Properties''' section of the dialog becomes enabled. Here you can specify the '''Source Amplitude''' in Volts (or in Amperes in the case of PMC traces) and the '''Phase''' in degrees.
* If the workspace contains an array of line or polyline objects, the array object will be listed as an eligible object for gap source placement. A lumped element will be placed on each element of the array. All the lumped elements will have identical direction, offset, resistance, inductance and capacitance values. If you define an active lumped element, you can prescribe certain amplitude and/or phase distribution to the gap sources. The available amplitude distributions include '''Uniform''', '''Binomial''' and '''Chebyshev'''. In the last case, you need to set a value for minimum side lobe level ('''SLL''') in dB. You can also define '''Phase Progression''' in degrees along all three principal axes.
[[File:wire_pic15.png]] [[File:wire_pic16_tn.png]]
The [[MoM3D Module]]'s lumped element dialog and an active lumped element with a voltage gap in series with an RC circuit placed on a dipole wire.
=== Defining Ports ===