Patent ID: 8806307

Claim:
A method of decoding a representation of a codeword that encodes K information bits as N>K codeword bits, the method comprising: (a) importing the representation of the codeword from a channel; (b) in a plurality of decoding iterations, updating estimates of the codeword bits, wherein the updating includes, in a graph that includes N bit nodes and N−K check nodes, exchanging messages between the bit nodes and the check nodes; and (c) interrupting the decoding iterations if an interruption criterion, that includes an estimate of mutual information between the codeword and a vector that is used in the decoding iterations, is satisfied, wherein the interrupting includes modifying at least one element of at least one vector associated with the decoding and then resuming the decoding iterations, wherein the vector, the estimate of mutual information between which and the codeword is included in the interruption criterion, is a vector of N LLR estimates Q of the codeword bits and wherein the estimate of mutual information is 1 E ⁢ ∑ 1 - log 2 ⁡ ( 1 + ⅇ -  Q  ) , where E is a number of edges in the graph.