Fall 2008

Page last updated 7 October 2008.

Latest Announcements

7 October 2008: The first drafts of project proposals are due for everyone on Wednesday October 15. See the timtable below. Also, Andrew's office hours have been moved to Tuesdays.

26 September 2008: I have added some links: to a brief introduction to Ansoft Designer, and a somewhat longer guided tutorial on the use of Ansoft Designer.

Course Information

Notes: In this course, you will study microwave transmission-line and antenna structures from the experimental point of view. In the process, you will also become familiar with some of the instruments that permit accurate microwave measurements to be made. No text is used; course notes (including the experiments) are available in PDF form for download  here . You must use the username

ecen_4634

and the password given out in class. The file can be read and printed using the free  Adobe Acrobat Reader software. Use only the 2008 version of the notes, and not earlier ones.

Software: For many of the homework problems and lab write-ups, you will need access to a microwave/RF circuit analysis program, such as Ansoft Designer. You will also need access to a version of the SPICE circuit analysis program in order to work one or two of the homework problems. Any version is okay, so long as it supports transmission line sections as circuit elements, as well as nonlinear voltage-controlled current sources. Several free versions of SPICE can be found on the Internet. If your version of a particular program does not have its own suitable plotting capability (or if you need to plot versus a variable other than frequency or time), you will have to prepare plots using other software (such as Excel, Gnuplot, Matlab, etc.) which you are going to need anyway for other parts of your lab reports and homework. See SPICE Hints for some tips on the usage of SPICE particularly relevant to this course. Programs in all these categories, and more, can be found at the software links below.

ECEN 5634 students will also need some kind of mathematical numerical analysis software capable of solving matrix equations in more than one unknown (i. e., solving linear systems of equations), or alternatively of minimizing a function of several variables. Examples of such software are: Mathcad, Matlab, Mathematica, Excel (with the Solver add-in),  Euler , Scilab , XLPlot , etc. I don't care which you use, but you will need to be reasonably self-reliant in its usage, because I am not expert in all such programs.

Lab Rules:  The laboratory room, ECEE 254, that we use for this course differs from lab rooms you may have used in other courses. It is NOT an open laboratory. Please read and understand the  lab rules . You are responsible for the proper use of the facilities.

Further Reading: If you are curious to learn more about RF and microwave measurements, I have put the following books on reserve at the Engineering Library:

• C. G. Montgomery (ed.), Technique of Microwave Measurements. New York: McGraw-Hill, 1947.

• E. L. Ginzton, Microwave Measurements. New York: McGraw-Hill, 1957.

• S. F. Adam, Microwave Theory and Applications. Englewood Cliffs, NJ: Prentice-Hall, 1969.

• G. H. Bryant, Principles of Microwave Measurements. Stevenage, UK: Peter Peregrinus, 1993.

• D. Pozar, Microwave Engineering. New York: Wiley, 1997.

• (Various authors), ARRL UHF/Microwave Experimenter's Manual. Newington, CT: American Radio Relay League, 1990.

Course Organization: There will be 11 experiments this semester, as well as a semester project. You must complete all of these to pass the course. If, with serious reason (medical emergencies qualify, workload from other courses does not) you miss one experiment, there will be make-up labs scheduled near the end of the semester. You must inform me ahead of time if you are going to miss a lab. If you arrive more than 15 minutes late for your lab section, you will not be allowed to do the lab, and will have to make it up during one of the make-up weeks.

Homework (the "pre-lab") is assigned for each experiment, and is due at the beginning of your lab section each week. For example, pre-lab homework number H5 is due at the beginning of the lab in which your group does experiment E5. See Prelab Homework Schedule below for which assignments you are responsible for. Students will not be allowed to do the lab work (and hence will not get credit for that week's experiment) unless their pre-labs have been handed in at the beginning of the lab session.  The purpose of the homework is to allow you to perform the experiments with some background and insight, rather than by the seat of your pants.

You should also read the assigned sections of the course notes prior to each week's lecture. There is a very limited amount of lecture time available for the many topics we cover in this course, so the lectures cannot go into each one in as much detail as we might wish. Also, some of the material should be a review for you from your previous EM Fields courses. I expect that you will read the notes and review basic EM concepts as needed in order to keep up; I will always be glad to help you with any questions you may have during my office hours since there will not be time for long answers during the lectures. Please feel free to come in for help.

Lab reports are due the day after your lab: Tuesday's sections by Thursday noon. Only these write-ups are used in determining your grade for each lab. They will be graded within 3 school days, and can be picked up in the lab during any of the lab sections or from the TA or myself during office hours. Grading of pre-labs and lab reports is as follows:

• 10 --- complete and all correct

• 8-9 --- complete and mostly correct

• 5-7 --- complete but some errors

• 3-4 --- complete but mostly wrong

• 0-2 --- incomplete or wrong

Please follow this guide to writing good lab reports when you write up your labs.

There will be a written final exam near the end of the semester. Here are some sample final exams from previous years (when the exam was in one part only).

FCQs (Faculty Course Questionnaires) will be administered online this semester. You should be receiving an email with instructions on how to fill out the online form. Information obtained via this questionnaire is very helpful in determining future improvements to the course, so please take the time to complete the form.

The schedule of experiments will be posted on this web page. Each group of lab partners will either be in an A Group or a B Group---this will be decided in class when lab partners are chosen. You should follow the schedule as posted, making sure to hand in solutions for the appropriate prelab homeworks (see  prelab schedule ).

Finally, there will be a semester project on which you will work for 3 or 4 weeks (undergraduates), or longer (graduate students). The undergraduate projects will be done in small groups, while each graduate student will do a separate project. Graduate students will perform a literature search at the beginning of the semester as background for selecting and planning their projects, and must submit a formal project plan by the first week of October.

Grades for the course will be determined as follows:

Undergraduate vs. Graduate Course Requirements: Undergraduate (ECEN 4634) students do all the labs and prelabs and a 3 to 4-week group project at the end of the semester. There is a TA for the two sections of ECEN 4634. The TA will grade the labs and prelabs for undergraduates.

Graduate (ECEN 5634) students do the same labs, but do a semester-long individual project, as well as some additional homework sets. There is no TA for ECEN 5634; I will be available during the lab, but graduate students are expected to work more independently. I do all the grading for graduate students.

You may discuss your labs with anyone you wish, but you must write up your lab reports and pre-labs yourself. Copying homework or lab reports from someone else (including your lab partners) or letting someone else copy from you is academic dishonesty, and will constitute grounds for failing the class. Please read the information on disabilities, religious observances, standards of behavior and academic integrity.

I and the TA will be available for questions regarding any aspect of the course during our respective office hours, which I hope will be such that everyone in the course can make use of at least some of them. In any case, you can also see me by appointment at other times. If you don't understand something, I'll never know until you ask or until you fail an experiment or an exam. Why not ask?

Lab Group Assignments

Prepare for the experiments each week according to the schedule indicated. Note: if the schedule says "no expt", it means there is no experiment that week, but I will be using the Tuesday lab section for a lecture period or some other purpose, and you should attend.
   

 
Lab Schedule
Please read the experiment description BEFORE you come to lab each week.

Prelab Schedule

Lecture Section Schedule

Projects

The final projects are INDIVIDUAL (ECEN 5634) or in GROUPS (ECEN 4634) and the experimental part starts in November. A draft project proposal (1 page) in electronic format (MS Word, LaTeX or PDF), must be submitted to me via email by Wednesday October 15. I will review each one and provide comments. The final project proposals are due by Wednesday October 22, also by email. Some possible project topics are listed below, but you are not limited to these. I will judge each proposal for suitability of level and effort required. Topics for graduate students should be related in some way to your research.

Format for project proposals: Use 2.54-cm (one-inch) margins, font 12pt, single-spacing. The title should be in font 14pt bold, centered. The names and affiliations, including email addresses, of the authors should be under the title in font 12pt. The text of the abstract should start 2 lines below the author name/affiliation. Your abstract needs to include the following information: (1) how the content uses things you have learned/ will learn in the class; (2) how the content expands what you have learned in class; (3) how the work will be distributed among team members for ECEN 4634; (4) a detailed weekly timeline and set of milestones for ECEN 5634.

The final project reports should be written in either MSWord or LaTeX in IEEE publication format. You should provide your report electronically to me via email as either a .DOC or .PDF file. Here is a sample file (warts and all) so you can learn the correct format for an engineering technical paper. There will be oral presentations of each project: 5 minutes for each graduate student project, 8 minutes for each undergraduate project (each member of the team must do at least part of the presentation). I will have a laptop set up for the presentations, and you should bring your files (either in Powerpoint or PDF format) on a memory stick or email them to me by 5:00 PM Friday December 12 so they can be loaded onto the laptop for the presentations on the next day. Please be sure that any necessary fonts, figures, etc. are embedded in your files.

Suggested Project Topics

• Solitons on Artificial Transmission Lines with Varactor Diodes
• Waveguide or Coax Slotted Line Measurements
• TRL Calibration Standard Design and Implementation (for Microstrip and/or CPW Circuits)
• Coupled Transmission Lines/Crosstalk in Transmission Lines
• Unusual Printed Transmission Lines (Coplanar Waveguide, Coplanar Stripline, Slotline)
• Dielectric Waveguides
• Attenuation Effects in Various Structures
• Tunable Matching Networks
• Advanced Time Domain Reflectometry (make new lab possibly)
• Periodic Structures: Interdigital, Meander, Comb and other Periodic Transmission Lines
• Baluns, Hybrid Couplers, etc.
• Filters
• Isolators and Circulators
• Diplexers and Multiplexers
• Dual-band Circuits (couplers, antennas etc.)
• Diode Detectors
• Oscillators
• Amplifiers and Repeaters
• Antenna Design and Measurement
• Antenna Arrays
• Microstrip Patch Antennas
• Monopulse Antenna Array for Direction Finding
• Ranging Radar
• Radar Jammer using a Mixer
• Measurement of Permittivity, Permeability and Conductivity
• Shielding: Wire Mesh, Metal Boxes, etc.
• Propagation Effects: Diffraction, Multipath, Clutter, etc.
• Upgrade Data Acquisition for the Artificial Line Experiment
  

I will also entertain your own topic suggestions ...

Some links of possible interest:

SOFTWARE

Ansoft Student Software

Ansoft offers feature-limited student versions of Ansoft Designer SV (high-frequency linear circuit simulator) and Maxwell SV (AC/DC electromagnetic and electrostatic-field simulator). From their web site: "Our free downloads are feature-limited, student versions of some of our commercially distributed software. Intended for electrical engineering students studying topics in electronic design, our free software fosters the development of engineering skills throughout the electronic-design community. Each download comes with a set of examples specially designed for topics commonly studied at the junior, senior, and graduate levels of study."

AppCAD

Free from Hewlett-Packard. Their Website description: "AppCAD is an easy-to-use program that provides you with a unique suite of RF design tools and computerized Application Notes to make your wireless design job faster and easier. AppCAD's unique, interactive approach makes engineering calculations quick and easy for many RF, microwave, and wireless applications. AppCAD is useful for the design and analysis of many circuits, signals, and systems using products from discrete transistors and diodes to Silicon and GaAs integrated circuits. The keyword for AppCAD is easy - no circuit files, no manuals - just quick and easy."

HbFree

"HbFree is a free Harmonic Balance Microwave and radio frequency circuit simulation program. It is intended for simulation of MW & RF analog non-autonomous circuits under multi-frequency excitations. It was developed for MW mixer and power amplifier design. It is a command-line program with no GUI interface. The package contains source codes of the harmonic balance simulator program hbl, the Spice-to-hbl translator s2h and a few utilities. It allows the following components to be used: R,L,C, transmission lines (lossless for now), V and I sources, diodes and MESFETs. The hbl simulator implements a piecewise harmonic balance technique with 2-D FFT to handle a fewsingle-frequency sources. The input language is very close to SPICE. The hbl simulator itself allows additional elements to be used: S- and Y- matrices of N-ports, strip- and microstrip transmission lines and some discontinuities. But these elements are not implemented in the s2h translator and are available in native hbl input format only." I have not tried it myself.

LTSpice / SwitcherCAD III

Free Windows high performance Spice III simulator, schematic capture and waveform viewer. Primarily intended for applications using the company's switching regulators, it is a very good general-purpose SPICE program, including transmission-line circuit elements.

OrCAD Demo Software

Free feature-limited circuit design software for Windows. The OrCAD Demo software includes demo versions of the following tools: OrCAD Capture, OrCAD Capture CIS Option, PSpice^® A/D, PSpice AA, OrCAD PCB Editor and SPECCTRA^® for OrCAD.

PUFF

Puff is an MS-DOS program for computer aided design and analysis of RF circuits. It was originally developed at California Institute of Technology (Caltech) by the research group of Prof. David Rutledge. You can freely download a copy of this program without a manual. More information is available at the Caltech website.

ViPEC

A free (for noncommercial use) circuit analysis program for UNIX or Windows, slanted towards RF and microwave work. Its primary advantage (at least in its present state of development) over SPICE is that it handles coupled transmission lines, and easily computes S-parameters and plots on Smith charts. On the other hand, it does not presently support nonlinear elements or other exotic things. From their web page: "ViPEC is a powerful tool for the analysis of high frequency, linear electrical networks. It takes a text based description of the electrical network and an analysis is performed in the frequency domain. The output is in the form of 2-port parameters (S, Y or Z) with results presented on a user defined grid and Smith chart. It can also be used to compute the input and output impedance/admittance as well as amplifier stability factors (Linvill & Stern). ViPEC supports various lumped elements (capacitors, resistors etc.) as well as distributed networks like transmission lines, microstrip and stripline structures. Two port data files are also supported e.g. the 2-port frequency parameters of various RF transistors as supplied by the manufacturer. The component library is under constant development with new elements added at regular intervals." Development seems to have come to a standstill since 2003.

atlc - Arbitrary Transmission Line Calculator

From their website: "Transmission lines, including directional couplers, of arbitrary cross section and an arbitrary number of dielectrics can be analysed with atlc. The impedance Zo of a two-conductor transmission line, as well as the odd-mode, even-mode, differential mode and common mode impedances of a directional coupler can all be computed with atlc. Tools to both analyse and synthesise directional couplers are available." atlc is primarily a UNIX or linux program, but ports to many other OSs have been made.

Fabian Kung's Home Page

Presents two useful Windows software programs for microwave and RF modeling. Windows FDTD 1.10 Software is Finite Difference Time Domain (FDTD) software by F. Kung for printed circuit board (PCB) modeling. "This software can model propagation of electromagnetic wave in a three-dimensional PCB structure, with lump components such as resistors, capacitors, inductors, diodes, and bipolar junction transistors. Sinusoidal and pulse voltage sources model are also included. The software runs on Windows platform (Win95 and above), and requires minimum 64 MByte RAM. Included with this version are utilities to view the output data and to draw the model." Windows Smith Chart/Impedance Matching Tool (1.15) is a simple and intuitive tool for viewing an impedance value in Smith chart. "The latest version also allows the user to perform L, T, Pi and single stub transmission line network interactive impedance matching/transformation. It is a versatile tool, which can be used to teach engineers and students on transmission line and impedance matching theory."

Fast Field Solvers

Freeware Windows software for the solution of Maxwell's equations and extraction of circuit parasites (inductance and capacitance), thanks to which equivalent circuits can be derived for simulation of EM behavior of a 3D structure with SPICE-like simulators. Common usages include the analysis of connectors, strip lines, IC packages, ram cells, etc.

FEMM Finite Element Method Magnetics

Freeware. From the reference manual: "FEMM is a suite of programs for solving low frequency electromagnetic problems on two-dimensional planar and axisymmetric domains. The program currently addresses linear/nonlinear magnetostatic problems, linear/nonlinear time harmonic magnetic problems, and linear electrostatic problems." FEMM is a Windows program, useful for getting numerical solutions of fields and line parameters for TEM and quasi-TEM modes on transmission lines, among many possible applications.

MMTL - Multilayer Multiconductor Transmission Line Electromagnetic Modeling Tools

Freeware tool for generating transmission parameters and SPICE models from descriptions of electronics interconnect (transmission line) dimensions and materials properties.

TX-Line Transmission Line Calculator

TX-Line is a free, easy-to-use, Windows-based interactive transmission line calculator from AWR. It can be used for the analysis and synthesis of transmission line structures. TX-Line enables users to enter either physical characteristics or electrical characteristics for common transmission media such as: microstrip, stripline, coplanar waveguide, grounded coplanar WG and slotline. TX-Line has an easy-to-use interactive graphical user interface and runs on Microsoft Windows 2000/XP.

Euler

A freeware numerical mathematics program similar in many ways to Matlab. It is available for Windows, Linux, Unix and OS/2 (this latter is no longer maintained). May be worth a look, though I haven't really used it myself.

Gnuplot

A portable command-line driven interactive data and function plotting utility for UNIX, IBM OS/2, MS Windows, DOS, Macintosh, VMS, Atari (!) and many other platforms. The software is copyrighted but freely distributed (i. e., you don't have to pay for it). It was originally intended as to allow scientists and students to visualize mathematical functions and data. It does this job pretty well, but has grown to support many non-interactive uses, including web scripting and integration as a plotting engine for third-party applications like Octave. Gnuplot supports many types of plots in either 2D and 3D. It can draw using lines, points, boxes, contours, vector fields, surfaces, and various associated text. It also supports various specialized plot types. Gnuplot supports many different types of output: interactive screen terminals (with mouse and hotkey functionality), direct output to pen plotters or modern printers (including postscript and many color devices), and output to many types of file (eps, fig, jpeg, LaTeX, metafont, pbm, pdf, png, postscript, svg, ...).

Scilab

A free mathematical software package for various Unix flavors and for Windows, somewhat more advanced in capabilities than Euler. From its website: "Scilab is a scientific software package for numerical computations in a user-friendly environment. It features:

• Elaborate data structures (polynomial, rational and string matrices, lists, multivariable linear systems,...).

• Sophisticated interpreter and programming language with Matlab-like syntax.

• Hundreds of built-in math functions (new primitives can easily be added).

• Stunning graphics (2d, 3d, animation).

• Open structure (easy interfacing with Fortran and C via online dynamic link).

• Many built-in libraries:

• Linear Algebra (including sparse matrices, Kronecker form, ordered Schur,...).

• Control (Classical, LQG, H-infinity,...).

• Package for LMI (Linear Matrix Inequalities) optimization.

• Signal processing.

• Simulation (various ode's, dassl,...).

• Optimization (differentiable and non-differentiable, LQ solver).

• Scicos, an interactive environment for modeling and simulation of dynamical systems.

• Metanet (network analysis and optimization).

• Symbolic capabilities through Maple interface.

• Parallel Scilab."

I have used it only sparingly myself.

Engauge Digitizer

"This open source, digitizing software converts an image file showing a graph or map, into numbers. The image file can come from a scanner, digital camera or screenshot. The numbers can be read on the screen, and written or copied to a spreadsheet." Very handy for comparing your own calculations with those someone else has previously published only in the form of a graph.

XL-Plot

Windows Freeware. From the website: "Create your graphs for scientific publication with XL-Plot. It reads ascii files and it outputs a vector drawing. XL-Plot is for Windows 95,98, 2000 and XP. The primary purpose of XL-Plot is to create a figure for scientific publication rapidly. It contains a few basic statistical functions, such as Students t-test and linear correlation of two sets of data (two columns in a spreadsheet). XL-Plot has a number of built-in functions that can be fitted to the data in columns on a spreadsheet or to a curve in a graph. The user can easily add fitting functions of his own design. Additional options are Fourier Transformation, (de-)convolution and Matrix inversion." It is a modest piece of software that does a surprising number of tasks well.

INFORMATION

Smith Chart Links

Various links containing information about the Smith chart, as well as Postscript and PDF files of the chart.

Impedance Matching

Various links containing information about impedance matching, including some Smith chart tools. Many of the links are to MathCAD files.

Microwaves 101

From their web site: "We're building a practical web resource covering the fundamental principles of microwave design, just for microwave engineers like you. Here you'll find:

• The basic concepts of microwave design theory in hypertext encyclopedic format! 
• Practical rules of thumb and other sage advice from Microwave O.F.s! 
• Useful microwave formulae presented in enter-and-click calculator formats! 
• The best microwave acronym and abbreviation dictionary anywhere! 
• A message board for technical and not-so-technical interchange!

The content on Microwaves101 is intended to be the following mix: Useful microwave information - 75%, Humor and assorted foolishness - 20%, Historical stuff - 15%, The remainder of 5% is stuff we've misplaced... We are here to help. If you can't get a response on the message board, send a question directly to the Unknown Editor. In-line content provided by vendors is intended to be useful technical information, not cheesy product releases."

SPICE Hints

Quick Guide to Ansoft Designer SV

Time-Domain Simulation with Ansoft Designer

Coaxial Connector Information

Information collected from a variety of sources about RF and microwave coaxial connectors.

Instructions for Circuit Etching

Agilent Interactive Model for S-Parameter Techniques

Agilent (né Hewlett-Packard) Application Note 95-1, "S-Parameter Techniques for Faster, More Accurate Network Design", discusses S-parameter techniques for designing networks used in amplifiers and oscillators. The basic theory behind using S-parameters to characterize any two-port network is presented, and the measurements of s-parameters for a transistor are summarized. Examples of using S-parameters to optimize amplifier and oscillator performance are presented and the optimization of the power gain of a narrow-band amplifier is used to illustrate the use of S-parameters and the Smith Chart in network design. This application note is in Adobe Acrobat (PDF) format and is bundled with QuickTime animations. It is available for download for all major computing environments. There is also an interactive Java^TM model that illustrates basic techniques for using S-parameters in network design.

Article on TDR

An article by David J. Dascher entitled "Measuring Parasitic Capacitance and Inductance Using TDR" from the Hewlett-Packard Journal. The article discusses TDR for transmission lines that have inductive or capacitive loads (in PDF, so Acrobat Reader or something similar is needed to view it).

S-Parameter Stuff

A collection of links to S-parameter related things (including the HP item above), courtesy of Spread Spectrum Scene magazine.

Network Analyzer Usage Tips

Some useful hints on operation of network analyzers.

Previous Announcements

22 September 2008: Andrew's office hours must be changed this week due to a time conflict. His office hours will be on Wednesday September 24 from 4 to 5:30 PM, rather than Monday, FOR THIS WEEK ONLY.

3 September 2008: Andrew's office hours have changed; see above.

22 August 2008: This page is still under construction. Dates and other parts of the schedule are subject to change. Note, however, that BOTH  LECTURE AND LAB SECTIONS WILL MEET FOR INTRODUCTORY LECTURES DURING THE FIRST WEEK OF CLASSES.

22 August 2008: The course notes and experiment descriptions are not sold in the bookstore; instead they are available for download in PDF form  here . The username

ecen_4634

must be used, along with the password supplied in class. Use only the 2008 version of the notes, and not earlier ones, as significant changes have been made. You will need to print out the experiment descriptions and have them with you when you do the labs. Otherwise, please do not waste paper needlessly: print the file only if you need to, and only those pages you really need hard copies of. Try to refer to the notes on your computer whenever possible. The file can be read and printed using the free  Adobe Acrobat Reader software.