Fig. 1
In this tutorial we will go through a transmission line problem. We will solve the problem
by creating a cross section of the transmission line and extracting the selected transmission
line parameters: capacitance, inductance, impedance and admittance.
See Fig. 1 for the cross section of the transmission line.
Fig. 1
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The
Maxwell control panel will appear on top of the screen, as shown in Fig.
2.
Fig. 2
2. We will now go into the Project Manager.
-select PROJECTS.
The Project Manager window will appear as shown in Fig. 3.
Fig. 3
3. Now we will create a project directory.
-select the Add in the Project Directories box
The add a new project directory window will appear.
-type the directory name in the Alias field (e.g., proj1) and then
select
the Make New Directory . Select OK.
4. We are now ready to start on the project.
-select New in the Projects box.
A window will appear.
-type in your project name in the Name field (e.g., microstrip)
and your name
in the Created By field.
-choose Parameter Extractor 2D for the Type field. Select
OK.
The new project name should appear in the Projects box.
5. We are now ready to enter the Simulator.
-select your project name and then select Open.
The
Executive Commands window should appear as shown in Fig. 4.
Fig. 4
6. Choose the parameters to be solved.
-select Requested Parameters.
The parameters window will appear.
-select All for this problem. Select OK.
7. Now we will draw the cross section of the micro strip.
-select Draw Cross Section.
The
2D Modeler Window will appear as shown in Fig. 5
Fig. 5
a. Set the drawing unit to be used.
-select Model --> Drawing Unit
The Drawing Units window will appear.
-select mils, then OK.
b. Draw the substrate.
-select Object --> Rectangle
Choose the position for the upper left corner.
-place the cursor at coordinates U,V(-20,0) then click the left
mouse button. The U and V fields are located at the bottom
of the window.
Choose the position for the lower right corner.
-place the cursor at coordinates U,V(20,-4) then click the left mouse button.
A New Object window will appear.
-type substrate into the Name field.
-to change the color to green, select the color button and select Green
from
the color palette. Select OK.
c. To make drawing the microstrip easier, zoom in to the top of the substrate.
-select Window --> Change View --> Zoom In. Create a box
around the top line of the substrate by clicking the left mouse button
at the upper left, then again at the lower right.
The top of the substrate should enlarge to fill the screen.
d. Draw the left microstrip.
-select Object --> Rectangle
Since the dimensions for the microstrip are very small it will be hard
to use the mouse to set the coordinates for the microstrip. To
work with small dimensions.
-select the U field and type in -12, tab to the V field and
type in 0.2, then select Enter to set the coordinates for
the upper
left corner.
-enter the coordinates (-10,0) for the lower right corner.
A New Object Window will appear.
-type left into the Name field and keep the color red.
e. Draw the right microstrip by copying the left.
-select the left microstrip, then select Edit --> Duplicate
--> Along Line.
You will now select the lower left corner of the left microstrip as the
anchor point .
-type -12 in the U field and 0 in the V field.
Set the target point.
-type 22 in the dU field and 0 in the dV field. Select Enter.
A window will appear. Leave the Total Number field at 2. Click on OK.
f. Rename the right microstrip.
-select Edit --> Attributes --> Rename.
A window will appear.
-type right in the Name field then select Rename. Select OK.
g. Draw the ground plane. (For the ground plane a rectangle
may be used, but we
will use a polyline for this illustration.)
-select Object --> Polyline.
Set the four coordinates of the polygon by clicking or typing into
the U and V fields.
-enter the following coordinates (-20,-4), (20,-4), (20,-4.2), (-20,-4.2)..
Change the object name to ground and make it color blue.
h. Save the model then exit from 2D Modeler.
8. Setup the conductors.
-select Setup Conductors.
The
Conductor Setup window will appear as shown in Fig. 6.
Fig. 6
-select left and right from the object box (make sure Multi.
Select button
is enabled when making more than one selection), then select
Conductor. Choose Signal line from the list of conductors.
Then select Assign.
- do the same for ground, assigning Ideal Ground to it.
Exit window and save changes before exiting..
9. Setup material.
-select Setup Materials.
The
Material Setup Window will appear as shown in Fig. 7.
Fig. 7
-select substrate in the background box, then select
FR4_epoxy in the material box. Click on Assign.
-by default ground, left and right is assigned perf_conductor
but the type of material assigned can be changed.
*
Note: To add a material to the material list the following material
attributes are needed:
1. Relative Permittivity
2. Relative Permeability
3. Conductivity
4. Imaginary Permeability
See Maxwell 2D Parameter Extractor User's Reference for details on how
to add materials.
Exit window and save changes before exiting.
10. Setup Boundaries/Sources.
-select Setup Boundaries/Sources. Choose Use Defaults setting.
11. Setup Solution Parameters.
-select Setup Solution Parameters. Choose Capacitance.
The Capacitance Solve Setup window will appear.
-change Percent refinement per pass to 25. Leave everything else
as is.
Select OK.
Go to Inductance Solve Setup window.
-change Percent error to 0.2.
Select OK.
Go to Impedance Solve Setup window.
-change Frequency to 1 kHz and Percent error to 0.2.
Select OK.
Go to Admittance Solve Setup window.
-change Frequency to 1 kHz and Percent error to 0.07.
Select OK.
12. Start solving for parameters.
-select Solve Parameters. Choose All.
13. View solutions.
-select Solutions . Choose Capacitance.
The capacitance matrix will appear as shown in Fig. 8. The value for left/left
and right/right are the self capacitance of each strip, while the left/right and
right/left values are for the mutual capacitance between the two strips.
-select Solutions and choose which matrix you want to view next.
Fig. 8
14. View Voltage/Flux Plot and Finite Element Mesh which is the basis of the parameter solutions.
-select View Fields. Pick a parameter.
The 2D Post Processor window will appear.
-select Post --> Plot --> Execute. This will generate voltage/flux plot as shown in Fig. 9.
-select Show --> Wire Mesh. This will generate the mesh used.
Fig. 9
-click on Print button in control panel
The Print Manager window will appear.
-set Print command to lp -d laser. Click on Save then OK.
2. To print plots and meshes:
-click
on
Print button in control panel. Then click with the left button
of the mouse, select the window and the part to be printed, then immediately
select with the right button and release..