Changes

Glossary of EM.Cube's Sources & Devices

2,709 bytes removed, 19:37, 16 February 2021
/* Conductive Sheet Trace */
[[Image:SOURCE MAN5.png|thumb|left|480px|The coaxial port source dialog.]]
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== Conductive Sheet Trace ==
 
ICON: [[File:voxel_group_icon.png]]
 
MODULE: [[EM.Picasso]]
 
FUNCTION: Defines a conductive sheet trace group
 
TO DEFINE A CONDUCTIVE SHEET GROUP:
 
# Right-click on the '''Conductive Sheet Traces''' item in the navigation tree.
# Select '''Insert New Conductive Sheet Trace...''' to open up the Conductive Sheet Trace dialog.
# Besides the color and texture properties, you have to enter values for the Electric Conductivity '''&sigma;''' in S/m and the sheet '''Thickness''' in the project units.
# Click the <b>OK</b> button of the dialog to return to the project workspace.
 
NOTES, SPECIAL CASES OR EXCEPTIONS: In [[EM.Picasso]], you may model imperfect metals using conductive sheet traces, which are an example of impedance surfaces. Keep in mind that you can typically model most lossless metallic traces such as micstorip lines and planar patches using PEC groups. A PEC trace is assumed to have an infinite electric conductivity and a zero metallization thickness. But also remember that since [[EM.Picasso]]'s simulation engine is based on the 2.5-D method of moments (MoM), lossy embedded dielectric objects with a large &sigma; cannot represent an imperfect metal because can only support vertical currents. A '''Conductive Sheet Trace''' group has a finite electric conductivity &sigma; and a small nonzero finite thickness expressed in the project units.
 
The conductive sheet traces are modeled using the surface impedance boundary condition stated above. If the thickness of the sheet is greater than the skin depth of the metal at the project frequency, then the surface impedance is given by
 
:<math> Z_s = \dfrac{1+j}{\sigma \delta}, \quad \delta = \sqrt{\dfrac{2}{k_0 Z_0 \sigma}} </math>
 
If the thickness t of the sheet is less than the skin depth, then the conductive sheet transition boundary condition is used instead, and the surface impedance is given by
 
:<math> Z_s = \dfrac{1}{[j k_0 Y_0 (\varepsilon_r - 1) + \sigma] \tau} = \dfrac{1}{\sigma_{tot} \tau} </math>
 
 
PYTHON COMMAND: conductive_sheet_group(label,sigma,thickness)
 
 
CONDUCTIVE SHEET PARAMETERS
{| class="wikitable"
|-
! scope="col"| Parameter Name
! scope="col"| Value Type
! scope="col"| Units
! scope="col"| Default Value
! scope="col"| Notes
|-
! scope="row" | sigma (&sigma;)
| Real Numeric
| S/m
| 5.8e+7
| electric conductivity
|-
! scope="row" | thickness
| Real Numeric
| project units
| 1.0
| finite metallization thickness
|-
! scope="row" | Locked mesh density
| Real Numeric
| cells/effective wavelength
| 30
| Only if "Lock Mesh" enabled
|}
 
<table>
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<td> [[Image:MATER MAN19.png|thumb|left|480px|The conductive sheet trace dialog.]] </td>
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</table>
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