Turbo Codes Based on Time-Variant Memory-1 Convolutional Codes over Fq
Abstract
Two classes of turbo codes over high-order finite fields are introduced. The codes are derived from a particular protograph sub-ensemble of the (dv=2,dc=3) low-density parity-check code ensemble. A first construction is derived as a parallel concatenation of two non-binary, time-variant accumulators. The second construction is based on the serial concatenation of a non-binary, time-variant differentiator and of a non-binary, time-variant accumulator, and provides a highly-structured flexible encoding scheme for (dv=2,dc=4) ensemble codes. A cycle graph representation is provided. The proposed codes can be decoded efficiently either as low-density parity-check codes (via belief propagation decoding over the codes bipartite graph) or as turbo codes (via the forward-backward algorithm applied to the component codes trellis). The forward-backward algorithm for symbol maximum a posteriori decoding of the component codes is illustrated and simplified by means of the fast Fourier transform. The proposed codes provide remarkable gains (~ 1 dB) over binary low-density parity-check and turbo codes in the moderate-short block regimes.
Cite
@article{arxiv.1102.4711,
title = {Turbo Codes Based on Time-Variant Memory-1 Convolutional Codes over Fq},
author = {Gianluigi Liva and Enrico Paolini and Sandro Scalise and Marco Chiani},
journal= {arXiv preprint arXiv:1102.4711},
year = {2016}
}
Comments
This paper has been withdrawn by the authors. To be presented at IEEE ICC 2011, Kyoto, Japan. June 2011