Walter Scott, Jr. College of Engineering

Graduate Exam Abstract

Zheng Wang
Ph.D. Final
May 18, 2011, 10am-12pm
ECE Conference Room
Channel Coding for Network Communication: An Information Theoretic Perspective
Abstract: Channel coding helps a communication system to
combat noise and interference by adding
``redundancy'' to the source message. Theoretical
fundamentals of channel coding in point-to-point
systems have been intensively studied in the field
of information theory, which was proposed by
Claude Shannon in his celebrated work in 1948. A
set of landmark results haven been developed to
characterize the performance limitations in terms
of the rate and reliability tradeoff bounds.
However, unlike its success in point-to-point
systems, information theory has not yielded as
rich results in network communication, which has
been a key a research focus over the past two
decades. Due to the limitations posed by some of
the key assumptions in classical information
theory, network information theory is far from
being mature and complete. For example, classical
information theoretic model assumes that
communication parameters such as the information
rate should be jointly determined by all
transmitters and receivers. Communication should
be carried out continuously over a long time
duration such that the overhead of communication
coordination becomes negligible. Communication
channel should be stationary in order for the
coding scheme to transform the randomness in
channel noise into deterministic statistics. These
assumptions, although reasonable in a point-to-
point system, do not permit an extensive
application of channel coding in network systems
because they essentially ignored the dynamic
nature of network communication. Network systems
deal with bursty message transmissions between
highly dynamic users. For various reasons, joint
determination of key communication parameters
before message transmission is often infeasible or
expensive. Communication channels can often be
non-stationary due to unexpected interference. The
objective of this work is to extend information
theory toward network communications scenarios. We
develop new channel coding results, in terms of
the communication rate and error performance
tradeoff, for several non-classical communication
models, in which key assumptions made in classical
channel coding do not hold.
Adviser: J. Rockey Luo
Co-Adviser: N/A
Non-ECE Member: Anton Betten, Department of Mathematics
Member 3: Louis L. Scharf, Electrical & Computer Engineering
Addional Members: Edwin K. Chong, Electrical & Computer Engineering
Journal Papers: 1. Z. Wang, J. Luo, "Approaching Blokh-Zyablov Error Exponent with Linear-Time Encodable/Decodable Codes," IEEE Communications Letters, Vol. 13, No. 6, pp. 438-440, June 2009. 2. Z. Wang, J. Luo, "Fountain Communication using Concatenated Codes," submitted to IEEE Trans. on Information Theory. 3. Z. Wang, J. Luo, "Error Performance of Channel Coding in Random Access Communication," submitted to IEEE Trans. on Information Theory. 4. Z. Wang, J. Luo, "Channel Coding for Random Multiple Access Communication," to be submitted to IEEE Trans. on Information Theory. Conference Papers: 1. Z. Wang, J. Luo, "Coding Theorems for Random Access Communication over Compound Channel," IEEE International Symposium on Information Theory, Saint Petersburg, Russia, July 2011. 2. Z. Wang, J. Luo, "Achievable Error Exponent of Channel Coding in Random Access Communication," IEEE International Symposium on Information Theory, Austin, TX, June 2010. 3. Z. Wang, J. Luo, "Concatenated Fountain Codes," IEEE International Symposium on Information Theory, Seoul, Korea, June 2009.
Program of Study: