Overview

NOTE: Use the Project Report Template

IN NO CASE may code or files be exchanged between students, and each student must answer the questions themselves and do their own plots, NO COPYING of any sort! Nevertheless, students are encouraged to collaborate in the lab session.

Part 1

• In this part, you will simulate coaxial lines using HFSS software.
• Impedance and phase characteristics will be determined.

• Load and run the pulse example as follows:
• Run HFSS from the linux window menu using Applications::ElectricalEngineering::Ansys HFSS
• If this is the first time you run the software, make a note of the location of the default directory (perhaps Ansoft or username/linux/Ansoft) that will be created for your projects
  
• Store all projects in this directory
  
• Download the following project file (you may need to hold down the shift key while you click on the link):
• newer version:  mwMetaProj8a.aedt  there is also an older version mwMetaProj8a.hfss
  
• Move the file into the HFSS directory
  
• Load the project from within HFSS using MenuBar::File::Open (red circle below)
  
• Double-click the "coaxAirWaveport1" design (red arrow below), and select the copper cylynder2 (blue arrow below), to see the corresponding 3D model (yellow arrow below)

Fig. 001

Fig001b

• Press the fitAll button (blue circle above), if the entire 3D model is not visible
• When you select the cylinder2 item (middle red arrow above), the corresponding 3D cylinder is highlighted
• Save a snapshot of the 3D model and paste it into your report.    
  
• Make sure that your plots, component values, legends, axes, and fonts are legible in your report!
• Click the "coaxAirWaveport1" design icon (upper left red box above) to see the variables used in the design (lower left yellow box above)
• From the variables, what is the length of the coaxial line? 
  
• From the variables, what is the radius of the inner conductor of the coaxial line? 
  
• From the variables, what is the radius of the outer conductor of the coaxial line? 
  
• Double-click the analysis setup icon (red arrow below) to observe the setup for the 3D solver
  

Fig. 002

• From the analysis setup, what is solution frequency (blue arrow above)? 
  
• Double-click the analysis setup sweep icon (red arrow below) to observe the setup for the 3D solver

Fig. 003

• From the sweep setup, what are start and stop frequencies (blue arrows above)? 
  
• Run the simulation
  
• Select the simulation tab (red circle below)
  
• validate the design (green arrow below)
  
• then run the simulation (blue arrows below)
  
• 
  

• In the bottom right, during any simulation (if you click the showProgress button in yellow box at the bottom below), you will see a progress bar (yellow circle below)
  
• If your project runs successfully, you should get a message (red circle below) if you click the showMessages button (in red box at bottom below) ,  where message may be  such as
•  [info] Normal completion of simulation on server: Local Machine. (8:30:17 PM  Feb 04, 2035)
  
• Observe the magnitude of S21 in dB by double-clicking the Results::s21dB (red arrow below)
• Observe the phase of S21 in degrees by double-clicking the Results::s21degrees (blue arrow below)

• Save a snapshot of the plot of the angle of S21 in degrees (yellow rectangle above with heading in red circle ) and paste it into your report.   
  
• At what frequency is the coaxial line section 90 degrees long? 
  
• At what frequency would the line length equal a quarter wavelength in free-space ? 
  
• Observe S21 in dB by double-clicking the Results::s21db (blue arrow above)
• What is the loss in dB of the coaxial cable at 1 GHz? 
  

• Next, select the results tab (blue arrow below)
• click the solutionsData button (blue circle below)

Fig. 006

• Select the matrixData tab (yellow circle above) and check the Zo box (left yellow arrow above)
• The impedance of the waveport gives the coaxial line impedance .  What is the impedance of the coaxial line (right yellow arrow above)? 
  

• Next, change the coaxial line material in the outer cylinder to polyethylene by right-clicking the "air" material (red arrow below) and selecting "properties"

Fig. 007

• In the materials popup, select polyethylene and OK (yellow arrows above)
• Rerun the simulation as before, but now with the polyethylene dielectric  and from 0.1 to 1 GHz

Fig. 008

• For the polyethylene coax, save a snapshot of the plot of the angle of S21 in degrees  and paste it into your report.   
  
• For the polyethylene coax, save a snapshot of the plot of  S21 in dB  and paste it into your report.   
  
• At what frequency is the polyethylene coaxial line section 90 degrees long? 
  
• Is the previous answer the same frequency where the polyethylene line length would equal a quarter wavelength in free-space ? 
  
• Using the same procedure as earlier in this project, what is the impedance of the polyethylene coaxial cable? 
  

• Identify and highlight  "waveport 1" (yellow arrow below) by selecting "excitation 1" (blue arrow below)
  

Fig. 009

• As shown above, select the rotateAroundScreenCenter button (red arrow above), and reorient the 3D model as shown.
• Once you have the model oriented as shown above, and with the "waveport 1" highlighted as shown above, save a snapshot of  and paste it into your report.   
  

• Exit the program, File->Exit

Report Data

• ============================    WARNING !!    ====================================
  
• **** WARNING **** YOU MUST USE THE PROJECT REPORT TEMPLATE Below:
• See the Project Report Template at bottom of this page
  
• A well-written report/paper is EXPECTED
  
• STRONGLY RECOMMEND that you read IEEE authorship series: How to Write for Technical Periodicals & Conferences
• Clearly describe everything, including:
• variables in block diagrams
• variables in formulas
• units of variables kHz, pF, nH, m, s,
  
• all traces on plots
• all curves on plots
• all results in any tables
  

• Minimum required data content for your report and demos
• Required theory/formulas numbered as below:
• (1) Coaxial cable formula for characteristic impedance Z0
  
• Required figures numbered as below:
• Any illegible plots receive zero credit (must be able to read all numbers, axes, labels, curves, grids, titles, legends)
• All plots must of professional quality as in IEEE papers
  
1.  LEGIBLE snapshot of the 3D model as in Fig. 001b above, with appropriate caption.
   
2.  LEGIBLE For the polyethylene coax noted below Fig. 007, a plot of  S21 in dB from 0.1 to 1 GHz as in Fig. 008, but scaled nicely
   
3. LEGIBLE For the polyethylene coax noted below Fig. 007, a plot of the phase of S21 in degrees from 0.1 to 1 GHz as in Fig. 008, but scaled nicely
4.  LEGIBLE snapshot of the waveport as illustrated in Fig. 009 above
   
• Required tabular data content:
1. Table of Fig 001 parameters  with 3 columns: parameter, value, units
   
• Row 1:  length of the coaxial line
  
• Row 2: radius of the inner conductor of the coaxial line
• Row 3: radius of the outer conductor of the coaxial line
• Row 4: relative permittivity of polyethelene material between inner and outer conductor of the coaxial line
• Row 5: theoretical impedance of the polyethelene coaxial line
• Row6: HFSS MatrixData Z0  for polyethelene simulation (as in Fig 006, but for polyethelene)

NOTE ReportTemplate: Use the Project Report Template 

  YOU MUST ADD CAPTIONS AND FIGURE NUMBERS TO ALL FIGURES!! 

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