Simplified sum-product algorithm for decoding LDPC codes with optimal performance

A simple, yet effective decoding algorithm is proposed for low-density parity-check (LDPC) codes, which significantly simplifies the check node update computation of the optimal sum-product algorithm. It achieves essentially optimal performance by applying scaling in the decoder´s extrinsic information. If no such scaling is applied, then the proposed algorithm has small performance degradation, e.g. in the order of 0.1 to 0.2´dB, depending on the coded block size.