Finite alphabet iterative decoders for LDPC codes surpassing floating-point iterative decoders

Shiva K. Planjery (1, 2) , David Declercq (2) , Ludovic Danjean (2, 1) , Bane Vasic (1)

1 ECE - Department of Electrical and Computer Engineering [Tucson]
2 ETIS - UMR 8051 - Equipes Traitement de l'Information et Systèmes

Introduced is a new type of message-passing (MP) decoders for lowdensity parity-check (LDPC) codes over the binary symmetric channel. Unlike traditional belief propagation (BP) based MP algorithms which propagate probabilities or log-likelihoods, the new MP decoders propagate messages requiring only a finite number of bits for their representation in such a way that good performance in the error floor region is ensured. Additionally, these messages are not quantised probabilities or log-likelihoods. As examples, MP decoders are provided that require only three bits for message representation, but surpass the floating-point BP (which requires a large number of bits for representation) in the error-floor region.

Domaines: Théorie de l'information [cs.IT]; Théorie de l'information et codage [math.IT]

Shiva K. Planjery, David Declercq, Ludovic Danjean, Bane Vasic. Finite alphabet iterative decoders for LDPC codes surpassing floating-point iterative decoders. Electronics Letters, 2011, 47 (16), pp.919-921. ⟨hal-00670723⟩