We present Kovalenko's full-rank limit as a tight lower bound for decoding
error probability of LDPC codes and LT codes over BEC. From the limit, we
derive a full-rank overhead as a lower bound for stable overheads for
successful maximum-likelihood decoding of the codes.Comment: A short version of this paper was presented at ISITA 2008, Auckland
NZ. The first draft was submitted to IEEE Transactions on Information Theory,
2008/0