Near optimal reduced-complexity decoding algorithms for LDPC codes

In this paper, two families of reduced-complexity algorithms for decoding low-density parity-check (LDPC) codes based on incorporating either a normalization or a correction term in the check-node update are presented. A simplified symbol-node update can also be used. Using simulations, it is shown that these simplified belief propagation (BP) approaches provide near optimum performance with different classes of LDPC codes.