Signal Processing and Coding Methods for High-Density Flash Memory Systems

我们开发并表征了新的信号处理和编码方法，以提高闪存的容量和寿命。我们研究了基于格理论的最优WOM码构造，并利用格和一些成形区域的交集开发了一种最优码构造。 为了提高可靠性，我们的编码调制方法相结合的格子和里德-所罗门码提高了信噪比1.8 dB，比现有的闪存代码使用BCH码。并提出了一种基于互信息最大化的信道量化方法。

We developed and characterized new signal processing and coding methods to improve the capacity and longevity of flash memories. We investigated optimal WOM code constructions based on lattice theory and developed an optimal code construction using the intersection of a lattice and some shaping region. To increase reliability, our coded modulation method combining lattices and Reed-Solomon codes improves the SNR by 1.8 dB over existing flash memory codes using BCH codes. And, we developed an effective channel quantization method based on the maximization of mutual information.