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Title:
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LDPC Code Design for Half-Duplex Decode-and-Forward Relaying |
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Author:
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Chakrabarti, Arnab; de Baynast, Alexandre; Sabharwal, Ashutosh; Aazhang, Behnaam
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Type:
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Conference Paper |
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Keywords:
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relay; LDPC; decode-and-forward |
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Citation:
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A. Chakrabarti, A. de Baynast, A. Sabharwal and B. Aazhang,"LDPC Code Design for Half-Duplex Decode-and-Forward Relaying," in Allerton Conference on Communication, Control and Computing, |
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Abstract:
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We propose LDPC code designs for the half-duplex relay channel. Our designs mimic the
information theoretic random coding scheme for decode-and-forward relaying. An important
advantage of our scheme is that it is built entirely of single-user codes that can be decoded by
belief propagation. The optimization of relay LDPC code profiles presents unique challenges,
which are met by using the density evolution algorithm with additional constraints for relaying.
To speed up our optimization, we use a Gaussian approximation of density evolution that converts
the infinite dimensional code profile optimization into a simple linear programming problem. The
thresholds of the discovered relay code profiles are within 0.4 dB of the achievable lower bound
for decode-and-forward relaying. |
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Date Published:
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2005-09-01 |
