Patent ID: 8250449

Claim:
A decoding method for low density check codes based on Belief Propagation algorithm, iteratively performing decoding between check nodes LLR(r mn ) and variable nodes LLR(q mn ) and comprising the following steps of: 110 ) initializing LLR (q mn ) using a received low density parity code bit stream; 120 ) updating the check node LLR(r mn ) and variable node LLR (q mn ): after updating the LLR(r mn ) corresponding to nonzero elements in each row in check matrix H in each iteration, immediately updating the LLR (q mn ) corresponding to all the nonzero elements in a column which corresponds to the nonzero elements in the row, and repeating the updating row by row; 130 ) updating LLR (q n ) on the basis of LLR(r mn ); 140 ) processing iteration termination judgment according to a maximum number of allowed iterations or whether the equation of H{circumflex over (x)} T =0 is satisfied, and outputting the final decoding result x n ; wherein q mn is extra-decoding information, q n is a bit likelihood ratio, r mm is extrinsic information, LLR is a log likelihood ratio and {circumflex over (x)} n is a corresponding decision result of LLR(q n ).