Plotting Wave Impedance along a Line
Description
This recipe generates a 2D plot of wave impedance in ohms vs. length for a line geometry. Wave impedance is obtained directly by taking the ratio of the transverse components of the electric field to the ratio of the transverse components of the magnetic field.
Where
is the transverse component of the electric field,
and 
is transverse
component of the magnetic field.
Usage Examples
This calculation could be used to display wave impedance vs. position along a length of waveguide with a changing cross-section. It could also be used to display the changes in wave impedance in free space at some boundary (e.g., frequency selective surface, radome) when performed on an incident wave problem.
Prerequisites
The line along which the impedance is to be plotted should be defined before performing this calculation. You can generate a line using Modeler>Draw>Line.
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Calculator Operation |
Resulting Stack Display (top entry only unless noted) |
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Quantity>E |
CVc : <Ex, Ey, Ez> |
|
Smooth |
CVc : Smooth(<Ex, Ey, Ez>) |
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Complex>CmplxMag |
Vec : CmplxMag(Smooth(<Ex, Ey, ... |
|
Number>Vector>{enter unit vector in direction of propagation} |
Vec : <0, 0, 1> (Z-directed unit vector used for example) |
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Cross |
Vec : Cross(CmplxMag(Smooth(<... |
|
Mag |
Scl : Mag(Cross(CmplxMag(Smooth... |
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Quantity>H |
CVc : <Hx, Hy, Hz> |
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Smooth |
CVc : Smooth(<Hx, Hy, Hz>) |
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Complex>CmplxMag |
Vec : CmplxMag(Smooth(<Hx, Hy,... |
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Number>Vector>{enter unit vector in direction of propagation} |
Vec : <0, 0, 1> (Z-directed unit vector used for example) |
|
Cross |
Vec : Cross(CmplxMag(Smooth(<... |
|
Mag |
Scl : Mag(Cross(CmplxMag(Smooth... |
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/ |
Scl : /(Mag(Cross(CmplxMag(Sm... |
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Add Type: Zwave OK |
Zwave : /(Mag(Cross(CmplxMag(… (User defined Named Expression Zwave is added) |
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Done |
{exit field calculator window} |
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HFSS>Results> |
{2D graph displayed} (y axis is wave impedance in ohms and x axis is position along line in drawing units) |