一种MLC闪存存储系统的比特翻转译码算法

Bit-flipping decoding algorithm for the MLC flash memory

随着多级存储单元比特存储密度的增加,单元间干扰成为影响闪存可靠性的主要因素.针对这种情况,在深入分析多级存储单元内部数据存储信道错误规律的基础上,设计了多级存储单元闪存译码的比特翻转规则,提出了一种适用于多级存储单元闪存的改进型比特翻转译码算法.仿真结果表明,在相同的感知精度时,所提出的多级存储单元闪存比特翻转算法的译码性能优于多级存储单元闪存比特翻转译码算法的性能,而且多级存储单元闪存的改进型比特翻转译码算法可有效减少译码的平均迭代次数,从而实现了译码复杂度和性能间的良好折中.

As the bit storage density of the multi-level cell （MLC） for flash memory increases, cell-to-cell interference is the dominant distortion source of the flash memory. By making a thorough analysis of the error characteristics of the intra-cell hit storage channel, a bit-flipping （BF） rule for the MLC flash memory is designed, and an improved BF algorithm is presented for the MLC flash memory. Simulation results show that the decoding performance of the improved bit-flipping algorithm is better than that of the BF decoding algorithm for the MLC flash memory with the same sensing precision, and the improved BF decoding algorithm for the MLC flash memory can effectively reduce the average number of iterations, which can achieve a better tradeoff between decoding complexity and decoding performance.