IEEE Transactions on Information Theory
Upper bounds on the rate of LDPC codes
David Burshtein, Michael Krivelevich, Simon N. Litsyn, G. Miller
Abstract
We derive upper bounds on the rate of low-density parity-check (LDPC) codes for which reliable communication is achievable. We first generalize Gallager's (1963) bound to a general binary-input symmetric-output channel. We then proceed to derive tighter bounds. We also derive upper bounds on the rate as a function of the minimum distance of the code. We consider both individual codes and ensembles of codes.