Efficient Decoding of Turbo Codes with Nonbinary Belief Propagation

Charly Poulliat (1) , David Declercq (1) , Thierry Lestable (2)

1 ETIS - UMR 8051 - Equipes Traitement de l'Information et Systèmes
2 Samsung Electronics Research Institute

This paper presents a new approach to decode turbo codes using a nonbinary belief propagation decoder. The proposed approach can be decomposed into two main steps. First, a nonbinary Tanner graph representation of the turbo code is derived by clustering the binary parity-check matrix of the turbo code. Then, a group belief propagation decoder runs several iterations on the obtained nonbinary Tanner graph. We show in particular that it is necessary to add a preprocessing step on the parity-check matrix of the turbo code in order to ensure good topological properties of the Tanner graph and then good iterative decoding performance. Finally, by capitalizing on the diversity which comes from the existence of distinct efficient preprocessings, we propose a new decoding strategy, called decoder diversity, that intends to take benefits from the diversity through collaborative decoding schemes.

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

Charly Poulliat, David Declercq, Thierry Lestable. Efficient Decoding of Turbo Codes with Nonbinary Belief Propagation. EURASIP Journal on Wireless Communications and Networking, 2008, 2008, Article ID 473613, 10 p. ⟨hal-00521063⟩