UNC Charlotte Agilent ADS Tutorial (Project 1)

(Approx. 2 weeks)

Overview

The objective of the tutorial is to become familiar with the basics of Agilent ADS software.

NOTE: Use the Project Report Template and  keep answers to questions on consecutive sheets of paper with all plots at the end.

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.

Only turn in requested plots ( Pxx ) and requested answers to questions ( Qxx ).

Part 1

  • Start the software:

  • If ADS is not on the system menu (Mosaci->Engineering->ECAD->ADS), run it from the command line as: 
        Hpads
  • On occasion, HPADS may have an illegible pop-up pane when you first run ADS.  The safe way to handle this is to proceed to a unix workstation and read the message.  On PC's the problem is caused by a missing font, and a risky fix is to click the lower left button.  In older software versions, this usually results in choosing the default initialization of RF/digital setup.
  • Note: you may have printing problems. To solve this, see if you have a file ".XprinterDefaults" in your home directory. Move this file to ".XprinterDefaultsOld", and restart ADS ... it will write a new copy of this file that should enable printing.
    if this does not work, move your current ".XprinterDefaults" file to ".XprinterDefaultsOld", and try downloading .XprinterDefaults to your home directory. (To download you may need to hold down the "shift key" while you click on the link.) Select the LPDEST printer by File-->PrintSetup-->Options and select Default Printer ($LPDEST) on default_queue

  • You should get the starting window:

  • Create a new project "linecalc1" as shown below. Choose the "no help needed" option and click "finish" in the pop-up.

  • Access the linecalc program from the tools menu as shown below.

  • The linecalc tool should appear as shown below.

  • Use linecalc to compute the impedance Z0, and the effective dielectric of a microstrip line W=0.125 inch (125 mils) wide on H=1/16 inch (62.5 mils) FR4 substrate with relative dielectric constant 4 and with a 1/2 ounce copper (T=0.7 mils thick) of conductivity 6.0E7 S/m. Set the frequency to 10 GHz, and line length L = 1000 mils (1 inch).

    Press the analyze button to compute the line parameters. Note that Z0 gives the line impedance, K_EFF is the effective dielectric constant, and E_EFF isEffective electrical length of line.

    Copy the linecalc window and paste it into your report (see template above). Make sure that it is legible in your report! YOU MUST ADD CAPTIONS AND FIGURE NUMBERS TO ALL FIGURES!! (use snapshot in the system menu, or screen print and paint, or other tools, or from command line, or type xv at the command line... xv seems better for scaling and previewing the images to fit the page) ( P1 )

    Experiment with other types of transmission lines and different parameters.

  • Exit the program, File->Exit.

    • Part 2

  • Start the software:

  • Download the following tar-file (you may need to hold down the shift key while you click on the link):
    tpwx1.tar

  • When ADS first runs, you should have a new directory apps/agilent/ads (or hpeesof/ads) created in your home directory. Start ADS and find out which directory your version of ADS automatically opens. (Use the "up arrows" in ADS to step up the directory structure to figure out where ADS started.) Move the tar-file into the hpeesof/ads (or apps/agilent/ads or whatever your automatic start-up directory is) directory, and de-tar using the command 
        tar -xvf tpwx1.tar
  • You should find a new directory tpwx1_prj created in hpeesof/ads or whatever your default ADS startup directory is.

  • Run ADS

  • Go down through the directory tree to ads/tpwx1_prj/networks/rlc1.dsn, and double click that design file. You should see:

  • Double-click the schematic in the right half of the window, and the following schematic should appear.

  • Print the schematic and turn it in. ( P2 )

  • Double-click the "gear" icon (shown below) in the upper right of the window to simulate.

  • The data plotting window shown below should appear.

  • Click the "rectangular plot" icon (shown below) in the left of the window to simulate.

  • Drop the plotting box in the visible area, and in the pop-up window:

    Select DataSet -> S(1,1) -> Add -> dB
    Select DataSet -> S(2,1) -> Add -> dB
    The screen should appear as:

  • Click OK, and the following S-parameter plot should appear.

    S11 is a measure of the reflected wave as a function of frequency. S21 is a measure of gain. S-parameters will be investigated in greater depth in the next project.

    Print this and turn it in. ( P3 )

    • Part 3

  • Take the Agilent quicktour and read through the on-line manuals, then answer the following questions and turn them in. It is usually best to use online manuals accessable from an ADS window by Help::AgilEESofWebResources::ProductDocWebBased::AdvancedSearch

  • What is the difference between an ADS Project and an ADS Design? ( Q1 )

  • Can an S-parameter simulation controller be used to simulate group delay (Yes/No)? ( Q2 )

  • Harmonic Balance Simulation Controller cannot be used to simulate multitone simulation of circuits that exhibit intermodulation (True / False). ( Q3 )

  • ADS can create stacked plots when viewing simulation results (True / False). ( Q4 )

  • ADS can BOTH read and write (import and export) GDSII files. ( Q5 )

  • ADS can BOTH read and write (import and export) SPICE files. ( Q6 )

  • What is a PLC component in ADS?
    Hint: see Lumped Circuit Components section. ( Q7 )

  • What is a term component used for in S-parameter simulation in ADS? ( Q8 )

  • What does the parameter Shmod control in the BSIM3SOI_MODEL for SOI MOSFET's in ADS?
    Hint: see Nonlinear Devices Components section. ( Q9 )

    • Part 4

  • Start the software:

  • Download the following tar-file (you may need to hold down the shift key while you click on the link):
    pulse1.tar

  • Move the tar-file into the hpeesof/ads directory, and de-tar using the command 
        tar -xvf pulse1.tar
  • You should find a new directory pulse1_prj created in hpeesof/ads

  • Run ADS

  • Go down through the directory tree to ads/pulse1_prj/networks/pulse1.dsn, and double click that design file. Double-click the schematic in the right half of the window, and the following schematic should appear.  (1 mil = 1/1000 inch)

  • Print the schematic and turn it in. ( P4 )
    •
  • Double-click the transmission line and look at the variables in the pop-up menu.  Select the variables and observe the changing description at the bottom of the pop-up.
    •
    • <>
  • Double-click the "gear" icon (shown below) in the upper right of the window to simulate.

  • The data plotting window should appear.
  • Click the "rectangular plot" icon (shown below) in the left of the window to simulate.

  • Drop the plotting box in the visible area, and in the pop-up window:

    Select DataSet -> V1 -> Add
    Select DataSet -> V2 -> Add
    Select DataSet -> Vsrc -> Add

  • Drop a second plotting box in the visible area, and in the pop-up window:

    Select DataSet -> V1 -> Add
    The screen should appear as:

  • Click OK, and the following Time-domain plot should appear.

    Print this and turn it in. Use the File->Print pull-down menu or snapshot (snap a region only -- dont print the window pane). ( P5 )

  • Compute the impedance of the line. ( Q10 )

  • Compute Gamma 1 from the component values on the schematic (reflection coefficient at 1st reflection, at interface between source and transmission line) ( Q11 )

    Does the voltage agree with your computed reflection coefficient?

  • Compute Gamma 2 from the component values on the schematic (reflection coefficient at the reflection at far end of line, at the load) ( Q12 )

  • Compute Gamma 3 from the component values on the schematic (reflection coefficient at input, after "round-trip" return) ( Q13 )

    • Report

    Write any comments or observations you may have directly on the printouts. Type or clearly handwrite. Do not add extraneous pages or put explanations on separate pages unless specifically directed to do so. The instructor will not read extraneous pages!

    Only turn in requested plots ( Pxx ) and requested answers to questions ( Qxx ). All plots must be labeled P1, P2, etc. and all questions must be numbered Q1, Q2, etc.

    Turn in a separate sheet with answers to all of the specific questions above.

    Copyright © 2002 T. Weldon