Abstract: A realization of belief propagation algorithms based on the two-way schedule and a serial concatenated decod
ing algorithm for LDPC codes based on the matrix decomposition are presented. The performance of this new algorithm is systematically analyzed via the density evolution theory. Analysis and simulation results show that the serial concatenat
ed decoding algorithm demonstrates a higher convergence speed and has as good performance as the conventional belief propagation algorithm.

Key words: LDPC codes, serial concatenated decoding algorithm, belief propagation algorithm, density evolution theory