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arXiv · 1306.4009

On the Asymptotic Performance of Bit-Wise Decoders for Coded Modulation

Mikhail Ivanov·Alex Alvarado·Fredrik Brannstrom·Erik Agrell
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Abstract

Two decoder structures for coded modulation over the Gaussian and flat fading channels are studied: the maximum likelihood symbol-wise decoder, and the (suboptimal) bit-wise decoder based on the bit-interleaved coded modulation paradigm. We consider a 16-ary quadrature amplitude constellation labeled by a Gray labeling. It is shown that the asymptotic loss in terms of pairwise error probability, for any two codewords caused by the bit-wise decoder, is bounded by 1.25 dB. The analysis also shows that for the Gaussian channel the asymptotic loss is zero for a wide range of linear codes, including all rate-1/2 convolutional codes.

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Mikhail Ivanov, Alex Alvarado, Fredrik Brannstrom, Erik Agrell. 2013-06-17. On the Asymptotic Performance of Bit-Wise Decoders for Coded Modulation. https://doi.org/10.1109/tit.2014.2312726

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