Improved augmented belief propagation decoding based on oscillation

The augmented belief propagation (ABP) decoding using previous node selection methods for low-density parity check (LDPC) codes with a large number of short cycles is investigated on the additive white Gaussian noise (AWGN) channel in this paper. Based on the observations obtained from the investigation, a new node selection method is proposed. It is shown that oscillation plays an important role in the ABP decoding and needs to be controlled. It is also shown that the most possible variable nodes needed to stop oscillation in cycles should be selected and kept stable in correct values in the ABP decoding. A parallel decoding scheme is also proposed, which proves that a better method exists. Simulation results confirm that the new method outperforms the previous ones for short LDPC codes on the AWGN channel.