Generalised reliability-based syndrome decoding of LDPC codes

Aimed at bridging the gap between the maximum likelihood and the suboptimal decoding schemes for short or medium LDPC codes, a generalised ordered statistic decoding (OSD), in the form of syndrome decoding is presented in the paper. The OSD is invoked once when a nonzero decoding syndrome is returned for the preceded belief propagation (BP) or min-sum (MS) variants. With respect to the OSD) With all accumulative reliability metric for the BP in the logarithmic likelihood ratio (LLR) domain, we extend the metric to the BP in the probability domain. Furthermore, the OSD with the metric specific for the MS variants, shows all appealing trade-off between performance and complexity. Meanwhile, when determining the optimal error pattern estimation. all alternative designed to reduce the number of the required real additions proves to be effective. Copyright (C) 2008 John Wiley & Sons. Ltd.