Nonbinary group decoder diversity for decoding dense block codes

In this paper, we present a new and promising framework, called ldquogroup decoder diversityrdquo based on the observation that different non-binary Tanner graphs of the same binary code, decoded with a non-binary belief propagation decoder can have distinct convergence behaviors and fixed points. This framework is especially interesting for binary codes which are dense or locally-dense, and for which the usual binary iterative decoders perform far from the optimum curves. By using the diversity brought by decoding distinct Tanner graphs of the same code, we managed to have very good decoding performance for BCH codes over BPSK-AWGN and BSC channels.