[[EM.Ferma]] is [[EM.Cube|EM.CUBE]]'s 3D electrostatic, magnetostatic and quasi-static solver.
With EM.Ferma, one can explore the fields in the vicinity of charge distributions, voltage sources, and current sources. Transmission line characteristic impedance (Z0) and Effective Epsilon can also be obtained.
=== Voltage Sources ===
In EM.Ferma, Voltage Sources are applied to a specified PEC material group that exists in [[EM.Cube|EM.CUBE]]'s navigation tree. All CAD objects under the specified PEC group will act as Voltage Sources.
To add a new Voltage Source to a project, right-click on "Voltage Sources" on the navigation tree, and select "Insert Voltage Source...". In the Voltage Source dialog, select the PEC group to which the specified voltage will be applied. Enter any string as the Voltage -- a text string will be interpreted as a variable which can be used for parametric design, or a parameter sweep.
=== Charge Sources ===
Charge Sources in EM.Ferma apply a charge (or charge density) to a region defined by any of [[EM.Cube|EM.CUBE]]'s CAD objects.
Adding a new Charge Source is very similar to adding a new material in [[EM.Cube|EM.CUBE]]. Find the "Charge Source" group label in the navigation tree and select "Insert New Charge Source..." A dialog will prompt the user to decide whether charge for this group will be defined in terms of total charge or charge density. If charge density is chosen, the specified charge density will be applied to all CAD objects defined in the present Charge Source group. If total charge is selected, the specified total charge will be distributed amongst the total volume of all objects under the present material group.
=== Current Sources ===
=== Field Sensor ===
Just like other [[EM.Cube|EM.CUBE ]] Modules, EM.Ferma has a standard Field Sensor observable. To specify a Field Sensor, right-click on "Field Sensors" in the navigation tree and click "Add New...". The Field Sensor dialog allows the user to select the direction of the sensor, visualization type, and whether E-field output or H-field output will be shown during a sweep analysis.
In EM.Ferma, Field Sensors are also used to specify 2D solution planes for EM.Ferma's 2D solution mode. This will be detailed shortly.
=== Transmission Line Characteristics ===
In EM.Ferma's quasistatic mode, transmission-line [[parameters ]] Z0 and EpsEff are computed, in addition to output due to the Field Sensor, which is required to define the 2D solution plane. Text files corresponding to these observables will be placed in the project's working directory after each analysis.
== Domain and Boundary Conditions ==
=== Setting up a Transmission Line Simulation ===
To perform a Transmission Line simulation, first turn on Quasistatic simulation mode for a selected 2D Solution Plane, as shown in the figure at right. If an analysis is run with this option checked, the characteristic impedance (Z0) and Effective Epsilon will be computed for the corresponding 2D Solution Plane. This output can be found in appropriately-named text files in the project directory upon completion of the simulation. Fields and potentials at the selected 2D plane will still be computed. Many 2D quasistatic solutions can be obtained in the same analysis, if for example, your design contains many types of [[Transmission Lines|transmission lines]].
Quasistatic analysis can only be performed with a Dirichlet boundary condition with 0V specified on the boundaries.
== Version History ==
* First available in [[EM.Cube|EM.CUBE ]] 14.2
== More Resources ==