基于概率的LDPC码的BF改进算法研究

Improved BF decoding algorithm of LDPC codes research based on probability

为解决LDPC码的硬判决比特译码算法译码性能问题,提出了一种新的改进型的译码算法。当不满足校验方程的消息节点数目超过规定的极限时,就以概率p(p≤1)翻转,概率p与码字相互独立。通过选择适当的初始化p,这种改进型的BF算法不仅在译码性能上有所提高,而且当p=1时在信噪比条件下平均译码时间有所改善。

To solve the performance of LDPC code hard-decision decoding algorithm, a new method for improving hard decision bit-flipping decoding of low-density parity-check （LDPC） codes is proposed. Bits with a number of unsatisfied check sums larger than a predetermined threshold are flipped with a probability p （ p ≤ 1 ） which is independent of the code considered. The prob- ability p is incremented during decoding according to some rule. With a proper choice of the initial p , the proposed improved bit- flipping （BF） algorithm achieves gain not only in performance, but also in average decoding time for signal-no-noise ratio （SNR） values of interest with respect to p= 1.