Absorbing Sets of Generalized LDPC Codes

In this paper we propose a definition of Absorbing Sets for binary Generalized LDPC (GLDPC) codes. We show that under practical Max-Log iterative decoding, our AS definition enables a local description of the message evolution with the iterations, with a simplified model very similar to the one used for the analysis of Min-Sum LDPC decoding. Accordingly, these ASs exhibit a threshold behavior also in GLDPC codes.