ELEC 320 Class Notes, Fall 2007

August 27: Key Concepts in Signals & Systems (PDF file)

August 29:

• Frequency Response (PDF file)
• Bode Plots (PDF file)
• Insights for filter design (PDF)

August 31:

• Demonstration of first-, second-, and third-order filters
  • Notes on filter order
  • Original music filx.au and filx.wav
  • First-order filter fily1.au and fily1.wav
  • Second-order filter fily2.au and fily2.wav
  • Third-order filter fily3.au and fily3.wav

September 7:

• Audio of 3 cars passing microphone
• Classes of signals
• Illustration of sampling and analog vs. digital signals

September 10 & 12: Signal Operation Examples

September 17 & 19:

• Classes of systems
• System classification exercises

September 21: Possible Topics for Exam 1

September 25: Solution to Exam 1

September 26 - October 1:

• Steps in Computing Continuous-Time Convolution
• Convolution Example
• Convolution Exercises
• Try the Joy of Convolution applet

October 5 and 8:

• Matlab tutorial links from Prof. Nepal's labs on October 3 and 4
• Matlab program solutions to Lab 3 (lab3_sol.m) and Homework 7 (hw7_sol.m)
• Applications of convolution
  • The Joy of Convolution applet at http://www.jhu.edu/~signals/
  • Lab 4: Matched filters
  • Optical illusion
  • Head-related transfer function (HRTF)
    Original work at MIT and documentation
    Project at Rice
  • Channel impulse response in digital communications

October 10: Class notes on Chapter 2

October 17: Solution to in-class convolution quiz

October 12, 17, 19, & 24:

• MATLAB/Simulink program fsgen.mdl to experiment with Fourier series. To run the program:
  1. Download the file fsgen.mdl
  2. Start Matlab
  3. Type fsgen at the Matlab prompt
  4. Under the Simulation menu, choose Start
  5. Open the "slider gains" by double-clicking on them
  6. Click the binocular icon on the plots to rescale the axes, if necessary
  7. Try to build a square wave and a triangle wave
• Time domain and frequency domain for signals
• Fourier series notes

October 22: Solution to Exam 2

October 26: Instead of ELEC 320 class on Friday, October 26, you are required to attend a presentation by L-3 from 9:00-10:45 AM in the Art Building, Room 201.

October 29, 31, & Nov. 2:

• Examples of signal approximation
• Matlab program for truncated, trigonometric Fourier series: fstrun.m
• The Fourier Series Approximation applet at http://www.jhu.edu/~signals/
• Matlab program sqrfilt.m to find the response of a low-pass RC circuit with frequency response H(w) = 1 / (1 + j (w/w_c)) to a square wave using compact trigonometric Fourier series.
• Fourier series notes
• Matlab program for truncated, exponential Fourier series of triangle wave: fstrun_exp.m
• FS notes from another textbook

November 9: Fourier transform notes, pages 1-4 and pages 5-6

November 16: Solution to Exam 3

November 19 and 26: Fourier transform applications

• Time-shift and scaling properties
• Linear, time-invariant systems
• Amplitude modulation (AM)

November 26 and 28:

• Lab project update:
  • Project titles and abstracts
  • Guidelines on the project presentation, report, and schedule
• Some Fourier transform exercises

November 30:

• The Program for Undergraduate Research: Application deadline is Monday, February 4, 2008.
• Notes on sampling and reconstruction
• Check out SampleMania at the Johns Hopkins demo page: http://www.jhu.edu/~signals/
• Sampling illustration

December 3: Final Exam notes

• The final exam for ELEC 320 is scheduled for Thursday, December 6 at 3:30 PM in room RCHM 116.
• The final exam will be closed-book and closed-notes, except that you can bring one sheet of 8.5 inch by 11 inch paper containing any notes that you would like. You should also bring a calculator. Important formulas and transform tables will be provided for you.
• The final exam covers all of the course material. The ABET outcomes specify the important topics from the course. You may want to refer to the outcomes as you study.