Abstract:

Based on the oscillation phenomenon in the decoding of Q-LDPC (q-ary low-density parity-check) codes, a modified decoding algorithm was proposed. In each iteration, for oscillating variable nodes, the previous posteriori probabilities are added to the current posteriori probabilities to reduce effects of oscillating in decoding. From the computer simulation, the modified decoding algorithm can achieve better bit error rate and block error rate for short and middle length Q-LDPC codes.

Key words: q-ary low-density parity-check, belief propagation, oscillation