1202.2778 (Nicolas Macris et al.)

Polymer Expansions for Cycle LDPC Codes    [PDF]

Nicolas Macris, Marc Vuffray

We prove that the Bethe expression for the conditional input-output entropy
of cycle LDPC codes on binary symmetric channels above the MAP threshold is
exact in the large block length limit. The analysis relies on methods from
statistical physics. The finite size corrections to the Bethe expression are
expressed through a polymer expansion which is controlled thanks to expander
and counting arguments.

View original: http://arxiv.org/abs/1202.2778