# ECE 438: Digital Signal Processing with Applications

## Professor Boutin, Fall 2014

Message area:

• Hi fellow students, I talked to Prof. Mimi about hosting extra office hours next week before the final; Which day works best for everyone that is interested? Comment below, thanks
just put an 'X' next to which day works best
Monday : XXXXX
I will hold extra office hours on Monday 12-15-14 from 10am until noon.
Teusday :XX
Wednessday :XXXXXX
I will hold extra office hours on Wednesday 12-17-14 from 1pm until 3pm.
Thursday :X
I will hold my regular office hours on Thursday 12-18-14 (from 8:45 until noon).

## Course Information

• Instructor: Prof. Mimi
• Teaching Assistant: Trey Shenk
• Email: shenkt at purdue dot you know what
• Teaching Assistant: Ikbeom Jang
• Email: jang69 at purdue dot you know what
• Course Outline (Approximate schedule with detailed reference list)
• Course Syllabus
• Important Dates:
• Test 1: Friday October 10, 2014 Friday October 17, 2014
• Test 2: Friday December 5, 2014
• Final, TBA

## Lecture Blog

Lecture 1, 2, 3 ,4 ,5 ,6 ,7 ,8 ,9 ,10 ,11 ,12 ,13 ,14 ,15 ,16 ,17 ,18 ,19 ,20 ,21 ,22 ,23 ,24 ,25 ,26 ,27 ,28 ,29 ,30 ,31 ,32 ,33 ,34 ,35 ,36 ,37 ,38 ,39 ,40 ,41 ,42 ,43 ,44, final exam .

## Slectures

The cleaned up version of the slectures is here.

Post a link to your slecture page below the relevant topic. If you want to reserve a particular topic, write your name/nickname below the topic. Please no more than 4 students per topic. To build your slecture page, you should use the following templates.

• Topic 1: Fourier transform as a function of frequency ω versus Fourier transform as a function of frequency f (in hertz). (Make sure to give some examples, including some signal whose FT nvolves Dirac delta(s). For that signal whose FT involves Dirac delta(s), compute the FT two different ways: 1) by starting from the ECE301 FT pair and making a change of variable, and 2) using the CTFT formulas. Observe that the expressions for the FT are different. Then point out that one can transform one expression into the other using the scaling property of the Dirac delta.) DEADLINE September 19
• Topic 2: Definition of the "rep" and "comb" operators. (Note that there are two ways to define each of these operators: using multiplication/convolution with an impulse train, or using a summation formula without impulse-train. You should include both representations and explain how to go from one to the other.) DEADLINE September 19
• Topic 3: Fourier transform of "rep" and "comb". (Make sure to carefully explain how to compute the Fourier transform of an impulse-train. You do not need to prove the multiplication/convolution property of the CTFT, but state it clearly whenever you need to use it.) DEADLINE October 1
• Topic 4: Discrete-time Fourier transform (DTFT): definition, periodicity property, example (computation of DTFT of a complex exponential- no fudging!) DEADLINE October 1
• Text Slecture by Jacob Holtman 15 reviews needed here.
• Text Slecture by Fabian Faes 15 reviews needed here.
• Text slecture by Xian Zhang Do NOT REVIEW-- AND DO NOT CHANGE THIS TEXT WITHOUT PERMISSION
• Topic 5: Discrete-time Fourier transform (DTFT) of a sampled cosine. (Include Case 1) sampling rate above Nyquist rate, and Case 2) sampling rate below Nyquist rate.) DEADLINE October 3
• Topic 6: Nyquist Theorem, with proof and example DEADLINE October 6
• Topic 7: Frequency domain view of the relationship between a signal and a sampling of that signal. DEADLINE October 6
• Topic 8: Frequency domain view of downsampling (explain why decimator needs a lowpass filter before the downsampling). DEADLINE October 10
• Topic 9: Frequency domain view of upsampling (explain why interpolator needs a lowpass filter after upsampling). DEADLINE October 13

## Slecture Review

Guidelines

• You must review one slecture per topic. (You cannot review your own slecture, of course. So if you are the only person who completed a slecture on a given topic, then you are not required to write a review for that topic. )
• The maximum number of reviews for each slecture is written next to each slecture. First come first serve. You will notice that some slectures will not get any reviews. This is because the slecture was either not completed or did not include a question page.
• Write your review directly on the question page of the slecture you are reviewing. Let me know if you want an anonymous login.
• You can reserve a spot for a specific slecture by writing your name on the question space.
• Be nice! Be constructive! The authors worked really hard on this.

## A bonus point opportunity

Students in ECE438 Fall 2014 have the opportunity to earn up to a 3% bonus by contributing a Rhea page on a subject related to digital signal processing. To pick a subject, simply write your name next to it. Your page will be graded based on content as well as interactions with other people (page views, comments/questions on the page, etc.). The number of links to other courses and subjects will also be taken into account: the more the merrier! Please do not simply copy the lecture notes and do not plagiarize. Read Rhea's copyright policy before proceeding.

Topic Number Topic Description Student Name
1 Something related to CT or DT Fourier transform Name
2 Something related to Z-transform Fabian Faes
3 Embedded Fixed Point FFT Sutton Hathorn
4 Something related to CSFT Name
5 Something related to Quantization Name
6 Neil Armstrong Moon Landing Speech Analysis Randall Cochran
7 Inv. Z Transform Mike Deufel
8 Bluetooth Audio Processing Chloe Kauffman
9 Extended explanation of Fourier transform of Rep and Comb Ben Capano

# Honors Contract

Students pursuing the honors track have the option to honors contract ECE438. Sahil Sanghani was interested in medical applications of DSP, so he wrote slectures on the relevant coursework from ECE 637, Digital Image Processing. Access the slectures here.

## Alumni Liaison

Abstract algebra continues the conceptual developments of linear algebra, on an even grander scale.

Dr. Paul Garrett