Abstract:

To solve the problem that in the low-density parity-check (LDPC) code offset min-sum (OMS) algorithm, the selection of the offset factor is not accurate, this article proposes an OMS algorithm based on order statistics (OR-OMS). The algorithm uses two different offset factors to modify the check node update results. One offset factor is used to modify the first minimum value result, and the other offset factor is used to modify the second minimum value result. Use order statistics to perform theoretical analysis, and obtain the two optimal offset factor values. The proposed algorithm uses a hierarchical scheduling message delivery method to speed up the convergence speed of the algorithm. The simulation results show that compared with the traditional OMS algorithm, the decoding performance of the proposed algorithm can obtain a gain of about 0.35 dB, when the bit error rate (BER) is 10^-5, and the average iteration times can be reduced by up to 34.28%. Meanwhile, the proposed algorithm has better convergence performance.

Key words: low-density parity-check (LDPC) code, offset min-sum (OMS), order statistics, hierarchical scheduling