ECE 729 Theory of Information Processing and Transmission, Spring 2001
See
what we did in Spring 1997.
Syllabus
Homework Solutions.
You can download Shannon's original paper,
A Mathematical Theory of Communication,
which started the whole field of Information Theory.
Books about information theory.
R. M. Gray's book, Entropy and Information Theory,
is available free as a
PDF file.
References on Source Coding, Rate Distortion, and Multiple Descriptions
Information Theory
Resources Available on the web.
Class Schedule for Spring 2001
1/22 Monday. Went over comm. system diagram, "big picture",
list of topics we hope to cover.
1/24 Began discussion of variable length codes for data compression.
Key ideas: unique decodability, expected length of a codeword,
and high-probabilty letters should have short codewords.
Defined code, codebook, extension of a code.
Started discussion of prefix or instantaneous codes.
1/26 Derived the Kraft Inequality and started proof of McMillan's Theorem.
Assigned HW #1 DUE WED 1/31.
Extra copies of HW (on both sides of paper) are outside my office.
1/29 Proved McMillan's Theorem, Theorem on lower bound on E[l(C(X))].
Showed that Shannon-Fano codes achieve lower bound + 1.
1/31 Summarized what we've done so far. Introduced discrete memoryless
source (DMS) and discussed variable length codes for sequences
of source letters. For a DMS, shorter expected lengths (per
source letter) are possible by coding blocks of source letters
together. Introduced binary Huffman codes. Discussed entropy
as a measure of uncertainty.
Assigned HW #2 DUE WED 2/7.
2/2 Worked example for ternary Huffman codes. Started fixed length
codes for data compression. Started proof that H(p) is an
achievable rate.
2/5 Finished proof that for DMS's, the set of achievable rates is
exactly the interval [ H(p), infinity ). This included showing
that the set of achievable rates is closed and convex.
2/7 Review of Gaussian random variables, vectors, and processes.
Discussed "Sending Bits over the AWGN Channel." Binary channels,
the Binary Symmetric Channel (BSC).
No HW Assigned.
2/9 Introduction to error correcting codes. Hamming distance, dmin of a
code, decoding sets and their error-correction and error-detection
capabilities. Brief description of Reed-Solomon codes.
2/12 Started notes on The Discrete Memoryless Channel (DMC). Focused
on pages 4-8.
2/14 Proved achievability of rates < I(p x W) for the DMC, covering
pages 9-14. (Skipped 10.1 and 10.2)
Assigned HW #3 DUE WED 2/21.
2/16 Went over page 14.1 and properties of mutual information through
page 18. Stated Data Processing Lemma on p. 19.
2/19 Derived the Data Processing Lemma. Gave an alternative proof of
Fano's inequality, different from the one in the notes. Proved
the Weak Converse Theorem, but glossed over some details to be
discussed next time.
2/21 Showed that the hyptheses of the Data Processing Lemma are satisfied
by the RVs in the proof of the weak converse. Proved Lemma:
if P(u|v,w) does not depend on w, then P(u|v,w)=P(u|v). Applied
several times. Discussed the fact that a problem is not well posed
until you can write down the joint pmf of all basic RVs.
Assigned HW #4 DUE WED 2/28.
2/23 Defined lambda achievability, and discussed the strong converse
as compared with the weak converse (pp. 23.1-23.2). Introduced
the maximum probability of error criterion (p. 4) and compared
it to the average probability of error criterion used in the
original definition of achievable rate on p. 6. See also pages
35-37, where it is shown that for the DMC, a rate R is achievable
under the average probability of error criterion if and only if it
is achievable under the maximum probability of error criterion.
2/26 pp. 24-27: Notion of symmetric and weakly symmetric channels and
how to compute their capacity almost by inspection. Examples
include the BSC and BEC.
2/28 Outlined the Arimoto-Blahut Algorithm and a couple of lemmas.
Assigned HW #5: Write a program, e.g., in Matlab, to implement
the Arimoto-Blahut Algorithm. Your program should print out the
maximizing pmf vector and the corresponding capacity (in bits per
channel use). Test your program on the BSC with crossover
probability epsilon = 1/10 and on the BEC with epsilon = 1/10.
Use your program to find the capacity of the channel
W(.|1) = (2/3, 1/3, 0)
W(.|2) = (1/3, 1/3, 1/3)
W(.|3) = ( 0, 1/3, 2/3).
DUE WED 3/7.
3/2 Proved convergence of the Arimoto-Blahut Algorithm to the DMC capacity.
3/5 Started notes on the Gaussian channel, pp. 1-6.
3/7 Continued discussing the Gaussian channel, pp. 7-9.
Distributed two old exams.
3/9 Finished proof of forward theorem for the Gaussian channel, pp. 10-13.
3/12 NO CLASS - Spring Break
3/14 NO CLASS - Spring Break
3/16 NO CLASS - Spring Break
3/19 Went over problems from old exams.
3/20 TUESDAY Exam 1 - night exam in 3534 Engineering Hall from 7:15-8:30
Closed book, closed notes. Bring a calculator.
3/21 Went over Exam 1. Used the sampling theorem to show that a bandlimited
function cannot be time limited. Also argued that the set of
bandlimited function that is approximately time limited of duration T
has approximate dimension 2WT.
3/23 Returned Exam 1. Proved the weak converse for the Gaussian channel.
Extended results to the ideal bandlimited Gaussian channel.
Distributed handout covering material from lecture of 3/21.
Assigned HW #6 DUE FRI Mar. 30.
3/26 Distributed handout covering the ideal bandlimited Gaussian channel.
Distributed handout covering average mutual information for mixed
random variables. Covered notes on the Lloyd-Max Algorithm.
3/28 Started notes on Rate Distortion Theory, pp. 1-3.2.
3/30 Showed that R~(D) is nonincreasing and convex on [0,infinity).
Skipped proof of lemma on p. 5-5.1. Proved the converse on p. 6.
Proved lemma on p. 7.
Assigned HW #7 DUE FRI Apr. 6.
4/2 Proved the forward part of the rate-distortion coding theorem,
pp. 8-12.
4/4 Showed that R(D)=0 if and only if D >= ~D*, pp. 13-14. Evaluated
the rate distortion function for a Bernoulli sequence with Hamming
distortion, pp. 15-17.
4/6 Evaluated the rate distortion function for an i.i.d. source uniformly
distributed on {0,...,m-1} with the Hamming distortion, pp. 19-21.
Discussed the Shannon Lower Bound on the rate distortion function,
pp. 17-18.
4/9 Finished discussion of Shannon Lower bound. Skipped Arimoto-Blahut
Algorithm for computing the rate distortion function. Discussed
multiple descriptions.
4/11 Distributed handout on "Source Coding and Rate Distortion Theory
for Multiple Correlated Sources." Extra copies outside my office.
Summarized systems covered, went over pp. 1-3 giving a new proof
of the single-source source coding theorem (forward part).
Assigned HW #8 DUE WED Apr. 18. Extra copies outside my office.
4/13 Proved the forward part of the Slepian-Wolf Theorem, pp. 4-6.
4/16 Proved converse of the Slepian-Wolf Theorem, pp. 7-8. Discussed
Source Coding with Side Information, p. 9. Discussed time sharing
and convexity of the achievable rate region. Briefly discussion
Rate Distortion with Side Information, p. 10. Distributed handout
on Carathéodory's Theorem.
4/18 Handed out solutions to HW #8 and discussed the solution of Problem 4.
Handed out and went over a proof that the cardinality of the set U
on p. 9 of the notes can be restricted to the cardinality of Y + 2.
Handed out HW #9 DUE WED Apr. 25.
4/20 Engineering Expo - Classes Canceled.
4/23 Started notes on "Source Coding Revisited -- Discrete Stationary Sources."
Covered everything except pp. 4-5 and the top of 6.
4/25 Reviewed solution of Problem 3 on HW #8. Finished notes on
"Source Coding Revisited." Discussed solution of Problem 4 on HW #9.
Handed out HW #10 DUE WED May 2.
4/27 Discussed Lempel-Ziv Alg. pp. 1-2. Stated and proved Lemma on pp. 4-6,
which is a discrete version of a HW problem.
4/30
5/2
5/4
5/7
5/9