项目名称: NAND闪存系统中的纠错编码关键技术研究
项目编号: No.61202013
项目类型: 青年科学基金项目
立项/批准年度: 2013
项目学科: 计算机科学学科
项目作者: 肖旻
作者单位: 厦门理工学院
项目金额: 22万元
中文摘要: 随着存储密度的增加,单元间干扰和层间噪声日益严重,NAND闪存系统迫切需要功能更加强大的纠错码来保证数据的可靠性。空间耦合(spatially coupled,SC)码具有NAND闪存系统所要求的低复杂度编码结构、优异纠错性能、极低误码率等特点。鉴于此,本项目基于NAND闪存系统的分级调制(rank modulation,RM)结构,拟搭建"SC码-分级调制"迭代架构,并在此架构上利用有限码长EXIT方法和PEG算法设计SC码的编码结构,以进一步提高纠错性能;引入滑窗译码算法和最小和算法简化SC码的译码过程,以降低译码时延和复杂度,提高NAND闪存读写速度;同时借助软硬件仿真平台验证系统性能,并利用有限码长比例法则,从理论上分析NAND闪存系统中的SC码性能,探寻决定其性能的关键参数。本项目的研究成果为下一代闪存系统中的纠错码技术发展提供理论支持,并有助于推动SC码在实际通信系统中的应用。
中文关键词: NAND闪存系统;ECC-RM级联架构;两边类型LDPC码;多进制LDPC码;
英文摘要: Increase of storage density leads to severe inter-cell interference and noises in a NAND flash memory system which needs more powerful error correcting codes to protect the data. Spatially coupled (SC) codes possessing low encoding complexity, capacity-approaching performance and very low bit error rate (BER) can meet the main requirements of a NAND flash memory system. Based on the rank modulation structure, this project proposes to construct an iterative scheme of SC decoder and RM demodulator on which the encoding structure of SC codes are improved with finite-length EXIT chart and the PEG algorithm. The windowed decoding algorithm together with the min-sum algorithm is introduced to decrease decoding latency and complexity. Meanwhile, the performances of SC codes are simulated on software and hardware platforms. Furthermore the finite-length scaling law is used to analyze the system. This project will help to provide new technologies and theories about error correcting codes for next-generation flash memory systems and benefit the application of SC codes in other communication systems.
英文关键词: NAND flash memory system;concatenated ECC-RM scheme;two-edge type LDPC codes;non-binary LDPC codes;