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Type of Document Dissertation Author Li, Teng Author's Email Address tli@nd.edu URN etd-04202007-043049 Title THE DESIGN AND ANALYSIS OF SUCCESSIVE DECODING FOR CHANNELS WITH MEMORY Degree Doctor of Philosophy Department Electrical Engineering Advisory Committee
Advisor Name Title Daniel J. Costello Committee Member Nicholas Laneman Committee Member Oliver M. Collins Committee Member Thomas Fuja Committee Member Keywords
- multistaged decoding
- coding
- capacity
- LDPC codes
- ISI channel
- fading channel
- Markov
- EXIT chart
Date of Defense 2007-03-26 Availability unrestricted Abstract Many communication systems have to cope with channels with unknownand time-varying state, including fading, inter-symbol
interference, and more general finite-state Markov channels. This
work proposes a novel successive decoding paradigm, or more
specifically, a time-multiplexed transmission of multiple codes
with multi-staged reception, to address the two fundamental
aspects of these channels: the estimation of achievable
information rate and the design of a practical coding system.
The first part of this work shows that successive decoding under a
deep rectangular interleaver essentially decomposes the original
channel into a set of asymptotic memoryless subchannels with
semi-infinite preceding training symbols. The achievable
information rate of the original channel under a given input
distribution can be efficiently computed from this set.
Furthermore, the conventional coding system that separates
estimation from decoding can operate on these memoryless channels
without loss of mutual information. These results allow us to
characterize accurately the binary-input capacity of correlated
fading channels and to operate within 1.1 dB to the binary-input
capacity using AWGN channel optimized LDPC codes.
The second part of this work deals with the design of more
practical successive decoding with a small number of levels. The
main idea is to incorporate an irregular interleaving pattern and
when necessary iterative estimation decoding within each level.
These techniques provide a more flexible configuration of
successive decoding for balancing the performance and the delay.
The analysis of the achievable rate and the
extrinsic information transfer (EXIT) charts are proposed for code
rate allocation and for the efficient optimization of
interleavers. Both the optimal random interleaver and a good
construction of the deterministic interleaver are numerically
shown to have performance very close to its binary-input capacity
with a small number of levels.
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