Visiting Lecturer Program (20)

Published at: 2005-05-09

Dr. Masoud Ardakani
Speaker: Dr. Masoud Ardakani
Post-doctoral fellow
Department of Electrical & Computer Engineering, University of Toronto, Canada

Local Organizer: Dr. Javad Omidi

Title: Performance-Complexity Tradeoffs in Low-Density Parity-Check Codes
Time: Saturday, May 7, 2005
Location: Department of Electrical & Computer Engineering, Isfahan University of Technology, Isfahan

Abstract :

Iterative decoding algorithms are among the most important inventions
in the history of channel coding. This importance stems from their
extremely good performance with practical complexity. For example,
low-density parity-check (LDPC) codes together with iterative decoding
algorithms can approach the theoretical limits on data transmission
very closely. An important question, which is of interest to both
theorists and practitioners, is to understand how complexity of an
iterative decoding algorithms tradeoffs with its performance.

In this talk, we first give a quick tutorial on LDPC codes, their
structure, their decoding and different methods of their analysis.
Then, we introduce a novel extrinsic information transfer (EXIT) chart
analysis of LDPC codes, which significantly simplifies many difficult
optimization problems regarding the performance or the decoding
complexity of these codes. Finally we show how this analysis can be
used towards design of both performance and complexity of LDPC codes.

Many of the ideas presented here can be applied to other iterative
decoding systems and some of them have already been adopted by other
researchers.