Improving soft FEC performance for higher-order modulations via optimized bit channel mappings.

@article{Hger2014ImprovingSF,
  title={Improving soft FEC performance for higher-order modulations via optimized bit channel mappings.},
  author={Christian H{\"a}ger and Alexandre Graell i Amat and Fredrik Br{\"a}nnstr{\"o}m and Alex Alvarado and Erik Agrell},
  journal={Optics express},
  year={2014},
  volume={22 12},
  pages={
          14544-58
        }
}
Soft forward error correction with higher-order modulations is often implemented in practice via the pragmatic bit-interleaved coded modulation paradigm, where a single binary code is mapped to a nonbinary modulation. In this paper, we study the optimization of the mapping of the coded bits to the modulation bits for a polarization-multiplexed fiber-optical system without optical inline dispersion compensation. Our focus is on protograph-based low-density parity-check (LDPC) codes which allow… 

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References

SHOWING 1-10 OF 31 REFERENCES
Optimized bit mappings for spatially coupled LDPC codes over parallel binary erasure channels
TLDR
This paper study spatially coupled low-density parity check codes over parallel channels and optimize the bit mapper using BICM as the driving example and shows that for rate-loss free, circular (tail-biting) ensembles, a decoding wave effect can be initiated using only an optimized bit mappers.
Protograph based low error floor LDPC coded modulation
  • D. Divsalar, C. Jones
  • Computer Science, Business
    MILCOM 2005 - 2005 IEEE Military Communications Conference
  • 2005
TLDR
The decoding thresholds of the proposed codes, which have linearly increasing minimum distance in block size, outperform that of regular LDPC codes, and a family of low to high rate codes, with thresholds that adhere closely to their respective channel capacity thresholds, is presented.
On the Mapping of Low-Density Parity-Check Codes for Bit-Interleaved Coded Modulation
TLDR
This paper shows how to improve the performance of given LDPC codes by mapping the variable nodes of certain degree in a special way to the different bit levels by a downhill algorithm that uses a generalized discretized density evolution to calculate the thresholds.
Capacity-approaching bandwidth-efficient coded modulation schemes based on low-density parity-check codes
TLDR
The optimized irregular LDPC codes at each level of MLC with multistage decoding (MSD) are able to perform well at signal-to-noise ratios (SNR) very close to the capacity of the additive white Gaussian noise (AWGN) channel.
EXIT-Aided Bit Mapping Design for LDPC Coded Modulation with APSK Constellations
TLDR
The bit mapping technique is applied to the low-density parity-check coded modulation system with Gray-APSK constellations for the first time and a low-complexity bit mapper consisting of a structural bit interleaver and a demultiplexer is devised.
Next Generation FEC for High-Capacity Communication in Optical Transport Networks
TLDR
An LDPC-coded turbo-equalizer as a candidate for dealing simultaneously with fiber nonlinearities, PMD, and residual chromatic dispersion and how to combine multilevel modulation and channel coding optimally by using coded modulation are described.
Optimized variable degree matched mapping for protograph LDPC coded modulation with 16QAM
  • Yi Jin, Ming Jiang, Chunming Zhao
  • Business, Computer Science
    2010 6th International Symposium on Turbo Codes & Iterative Information Processing
  • 2010
TLDR
A VDMM optimization strategy, as a crucial part for the P-LDPC coded modulation, is proposed by checking different permutation patterns between the variable nodes in protograph and the modulated bits by developing a modified EXIT analysis.
Threshold of Protograph-Based LDPC Coded BICM for Rayleigh Fading
TLDR
This work presents a simple method for designing protograph-based BICM that is general and applies to any modulation, and furthermore it calculates the iterative decoding thresholds of the protograph codes while mapped to higher order modulations.
A Pragmatic Coded Modulation Scheme for High-Spectral-Efficiency Fiber-Optic Communications
TLDR
A pragmatic coded modulation system is presented that incorporates signal shaping and exploits the excellent performance and efficient high-speed decoding architecture of staircase codes, and it is shown that digital backpropagation increases the achievable spectral efficiencies.
Reliable channel regions for good binary codes transmitted over parallel channels
TLDR
This work investigates reliable channel regions which ensure reliable communications over parallel channels under maximum-likelihood (ML) decoding and studies the average error probability performance of binary linear code ensembles when each codeword is divided into J subcodewords with each being transmitted over one of J parallel channels.
...
1
2
3
4
...