DocumentCode :
1161433
Title :
Joint optimization of signal constellation bit labeling for bit-interleaved coded modulation with iterative decoding
Author :
Muhammad, Nabil Sven ; Speidel, Joachim
Author_Institution :
Inst. of Telecommun., Univ. of Stuttgart, Germany
Volume :
9
Issue :
9
fYear :
2005
fDate :
9/1/2005 12:00:00 AM
Firstpage :
775
Lastpage :
777
Abstract :
We optimize signal constellation and bit labeling for bit-interleaved coded modulation with iterative decoding (BICM-ID). Target is to minimize bit error rate floor and signal to noise ratio for the turbo cliff. Various optimal non-orthogonal 16-QAM mappings are presented. An improvement of 0.2 dB is shown compared to state of the art orthogonal QAM-constellation with approx. the same error floor. To obtain these results, we derive the probability density function of extrinsic L-values of the demapper for perfect a priori knowledge in closed form. This allows fast computation of mutual information in the EXIT chart.
Keywords :
error statistics; interleaved codes; iterative decoding; minimisation; modulation coding; probability; quadrature amplitude modulation; turbo codes; BICM-ID; EXIT chart; bit error rate; bit-interleaved coded modulation; iterative decoding; minimization; nonorthogonal 16-QAM mapping; probability density function; signal constellation optimization; turbo cliff; Bit error rate; Constellation diagram; Gaussian noise; Interleaved codes; Iterative decoding; Labeling; Modulation coding; Probability density function; Signal to noise ratio; Utility programs;
fLanguage :
English
Journal_Title :
Communications Letters, IEEE
Publisher :
ieee
ISSN :
1089-7798
Type :
jour
DOI :
10.1109/LCOMM.2005.09013
Filename :
1506699
Link To Document :
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