A SHUFFLED-BASED ITERATIVE DEMODULATION AND DECODING SCHEME FOR LDPC CODED FLASH MEMORY

In previous studies, a very sparse low-density parity-check (LDPC) code was designed for triple-level cell (TLC) NAND flash using non-Gray mapping, which is able to achieve comparable error-rate performance to the conventional Gray mapping-based scheme. Although a sparse LDPC code can be of benefit to hardware implementations of an iterative demodulation and decoding (IDD) scheme, difficulties emerge, such as latency issue between the decoder and demodulator, when compared to non-IDD schemes. In this paper, a hardware-friendly structure interleaver is used such that a shuffle-based IDD scheme can be realized efficiently. Compared to the conventional Gray-based non-IDD scheme and layered-based IDD scheme, the proposed shuffled-based IDD scheme can provide a better hardware efficiency and better error-rate performance.